WO2015107663A1 - Emergency stop system for work machine, work machine, and emergency stop method for work machine - Google Patents

Abstract

This emergency stop system for a work machine is provided with an emergency stop switch (45), work machine control devices (81, 82, 83) which can control stopping operations of the work machine, a power supply (40), a power supply line (401) which connects the power supply (40) and the work machine control devices (81, 82, 83), a first relay (41) and second relay (42), and a second relay control device (80) which controls the second relay. In an emergency state in which the emergency stop switch (45) has been actuated, the first relay (41) cuts off a power supply line (401). Upon detecting an emergency state in which the emergency stop switch (45) has been actuated, the second relay control device (80) cuts off the power supply line (401) at the second relay (42).

Description

Work machine emergency stop system, work machine and work machine emergency stop method

The present invention relates to an emergency stop system for a work machine such as a hydraulic excavator, a work machine, and an emergency stop method for the work machine.

In a working machine such as a hydraulic excavator, an emergency stop system is known in which an emergency stop switch is operated to stop a work machine in an emergency (see, for example, Patent Document 1).
The emergency stop system of Patent Document 1 includes two emergency stop switches, a first switch for stopping the engine other than the engine such as a work machine and a travel motor, and a second switch for stopping the engine including the engine. A stop controller, a work implement stop valve, and an engine controller are provided.
The emergency stop controller and the engine controller are connected to the battery via the ignition switch. If the ignition switch is in the on state, the emergency stop controller and the engine controller are supplied with electric power from the battery, and the operation state can be maintained.
The open / close state of the first switch and the second switch is detected by the emergency stop controller. When the emergency stop controller determines the ON state of each switch, the emergency stop controller outputs a stop command for stopping the work implement and the engine to the work implement control valve and the engine controller, thereby stopping the work implement and the engine.

JP 2008-248627 A

In Patent Document 1, the emergency stop controller detects the open / closed state of the first switch and the second switch, and the emergency stop controller generates and outputs a stop command for commanding the work machine and the engine to stop. For this reason, if an emergency occurs in the emergency stop controller and the open / closed state of each switch cannot be detected correctly, or a stop command cannot be generated and output, the work machine can be operated even if the operator inputs each switch. May not be able to stop. In such a case, it is necessary to stop the work machine and the engine by cutting off the ignition switch, and there is a problem that the stop operation is delayed.

An object of the present invention is to provide an emergency stop system for a work machine, a work machine, and an emergency stop method for the work machine that can reliably stop a work machine or the like when an emergency stop switch is operated.

The present invention is an emergency stop system for a work machine provided with a work machine, wherein an emergency stop switch, a work machine control device capable of controlling a stop operation of the work machine, and power is supplied to the work machine control device A power supply, a power supply line that connects the power supply and the work implement control device, a first relay and a second relay that are provided in the power supply line and control power supply to the work implement control device, And a second relay control device that controls the second relay by detecting an open / closed state of an emergency stop switch, wherein the first relay is controlled by the emergency stop switch, and the emergency stop switch is input to the emergency stop switch. In the state, the power supply line is disconnected, and when the second relay control device detects an emergency state in which the emergency stop switch is input, the second relay control device controls the second relay to supply the power. When the power supply line is cut by the first relay or the second relay and the power supply from the power source to the work implement control device is stopped, the work implement is stopped. And

In the present invention, when an operator inputs an emergency stop switch, the first relay controlled by the emergency stop switch is disconnected. Moreover, when the input operation of the emergency stop switch is input to the second relay control device, the second relay control device disconnects the second relay. For this reason, the power supply line that supplies power from the power source to the work implement control apparatus is disconnected by the first relay and the second relay that are connected in series to the power supply line. Therefore, the power supply to the work machine control device is also stopped, and the work machine is stopped.
In the present invention, when the emergency stop switch is input, two relays that stop power supply to the work implement control device that controls at least the stop operation of the work implement are arranged in series. Even if a failure occurs in the relay, the power supply can be reliably stopped by operating the other relay.
In particular, since the first relay is controlled by an emergency stop switch, an abnormality occurs in the second relay control device that controls the second relay by outputting a control signal, and the second relay cannot be normally controlled. However, since the first relay is disconnected, the power supply to the actuator control device can be reliably stopped.
Further, when the first relay is out of order, the second relay control device can control the second relay to a disconnected state, so that the power supply to the actuator control device can be stopped reliably.
That is, since the probability that both the first relay and the second relay fail simultaneously is very small, the power supply to the work implement control device can be reliably stopped when the emergency stop switch is operated. Since the operation of the work implement is automatically stopped by stopping the power supply to the work implement control device, the work implement can be reliably stopped when the emergency stop switch is operated.

In the emergency stop system for a work machine according to the present invention, it is preferable that the second relay disconnects the power supply line when a control signal is not input from the second relay control device.
For example, as the second relay, a normally open electromagnetic relay that turns on the power supply line when current flows through the coil of the electromagnet and disconnects when current does not flow may be used.

In the present invention, when an abnormality occurs in the second relay control device and a control signal cannot be output from the second relay control device, the power supply line can be disconnected by the second relay. For this reason, even if the emergency stop switch is not operated, when an abnormality occurs in the second relay control device, the power supply to the work implement control device can be stopped reliably, and the work implement can be reliably stopped.

In the work machine emergency stop system according to the present invention, the work machine control device includes a first control device that controls driving of the work machine and devices other than the work machine, and a second control device that controls driving of the work machine. The power supply line is provided with a third relay that controls only the power supply to the second control device, and only the second control device when only the third relay is disconnected It is preferable that the working machine controlled by the second control device stops.

Here, the devices other than the work machine controlled by the first control device are, for example, service arms (services) used for raising and lowering ladders for getting on and off the work machine, and supplying fuel to the work machine. Center).
According to the present invention, since the third relay is provided, it is possible to stop only the power supply to the second control device and stop the work implement. On the other hand, since power supply to the first control device can be continued, driving of devices other than the work machine can be continued. Accordingly, it is possible to drive a device other than the work machine while the work machine is stopped during maintenance work or the like, and the convenience can be improved.

In the emergency stop system for a work machine according to the present invention, a work implement stop switch for controlling the third relay is provided, the third relay is controlled by the work implement stop switch, and the work implement stop switch is input. In the state, it is preferable to cut off the power supply line and cut off the power supply to the second control device.

According to the present invention, when the work implement stop switch is input, the third relay is disconnected, the power supply to the second control device can be cut off, and the work implement controlled by the second control device can be stopped. Therefore, if the work implement stop switch is input when the ladder is lowered or the service arm is lowered, the work implement operates when the ladder or the service arm is lowered or when the PPC lock lever is locked. It is possible to prevent the ladder and the service arm from being damaged, and the safety in the work machine can be further improved.

In the emergency stop system for a work machine according to the present invention, the work machine is a hydraulic excavator that includes a traveling body and an upper swing body that is turnable on the travel body, and the upper swing body includes a ladder. Or it is preferable to provide a service arm.

In the present invention, since the work machine is a hydraulic excavator, if the upper revolving structure or the service arm descends from the upper revolving structure, if the upper revolving structure revolves, the ladder or service arm interferes with the traveling structure. There is a possibility of damage.
Therefore, according to the present invention, when the ladder or the service arm is lowered, the work machine controlled by the second control device is stopped by disconnecting the third relay by the input of the work machine stop switch or the like. it can. For this reason, in the hydraulic excavator, it is possible to prevent the upper swing body from turning and damaging the ladder and the service arm while the ladder and the service arm are lowered, and the safety in the working machine can be further improved. Furthermore, even if the third relay is disconnected, the power supply to the first control device can be continued. Since the first control device controls not only the work machine but also devices other than the work machine, the first control device can control the drive of the ladder and the service arm. Therefore, the ladder and the service arm can be driven in a state where the work machine controlled by the second control device is stopped, and safety and convenience can be improved.

The work machine of the present invention is a work machine including an emergency stop system for the work machine and a drive mechanism that drives the work machine, and the drive mechanism is supplied from a hydraulic pump and the hydraulic pump. A hydraulic drive device driven by hydraulic oil; and a hydraulic control valve that controls supply of hydraulic oil from the hydraulic pump to the hydraulic drive device, wherein the work implement control device controls the hydraulic control valve. The hydraulic control valve includes a valve controller that outputs a signal, and the first relay or the second relay is disconnected, the work implement control device is stopped, and the control signal is input from the work implement control device. When it disappears, it becomes the stop state which stops supply of the said hydraulic oil, It is characterized by the above-mentioned.

According to the working machine of the present invention, the above-described emergency stop system can provide the effect.

The present invention relates to a work implement, an emergency stop switch, a work implement control device capable of controlling a stop operation of the work implement, a power supply for supplying power to the work implement control device, the power supply, and the work implement control device. A power supply line connecting the power supply line, a first relay and a second relay provided in the power supply line for controlling power supply to the work implement control device, and detecting an open / closed state of the emergency stop switch, An emergency stop method for a work machine comprising a second relay control device for controlling a second relay, wherein the first relay disconnects the power supply line in an emergency state where the emergency stop switch is input. The second relay control device that detects an emergency state in which the emergency stop switch is input controls the second relay to disconnect the power supply line, and the first relay or the first relay If the electric power supply is the power supply line is disconnected by the relay from the power source to the working machine control device is stopped, the working machine is characterized in that stop.

According to the present invention, the same effect as the emergency stop system can be obtained. That is, when the operator performs an input operation on the emergency stop switch, the first relay controlled by the emergency stop switch is disconnected. Further, when the input operation of the emergency stop switch is detected by the second relay control device, the second relay control device disconnects the second relay. For this reason, the power supply line that supplies power from the power source to the work implement control apparatus is disconnected by the first relay and the second relay that are connected in series to the power supply line. Therefore, the power supply to the work machine control device is also stopped, and the work machine is stopped. In the present invention, since two relays that stop power supply to the work implement control device that controls at least the stop operation of the work implement are arranged in series, even if one of the relays fails, the other relay By operating the relay, the power supply can be reliably stopped. That is, since the probability that both the first relay and the second relay fail simultaneously is very small, the power supply to the work implement control device can be reliably stopped when the emergency stop switch is operated. Since the operation of the work implement is automatically stopped by stopping the power supply to the work implement control device, the work implement can be reliably stopped when the emergency stop switch is operated.

1 is a side view showing a hydraulic excavator according to an embodiment of the present invention. The figure which shows the whole structure of the hydraulic circuit of a hydraulic shovel. The figure which shows the structure of the operation control system of a hydraulic excavator. The figure which shows the structure of the operation monitoring system of the operating tool of a hydraulic shovel. The graph which shows the relationship between the operation amount and voltage value in a 1st operation signal and a 2nd operation signal. The schematic perspective view which shows the raising / lowering ladder of a hydraulic shovel. The schematic side view which shows the service arm of a hydraulic excavator. The block diagram which shows the structure of a master controller and a slave controller. The figure which shows the circuit structure of the emergency stop system of a hydraulic excavator. The flowchart which shows the hydraulic drive control method of a master controller and a slave controller. The flowchart which shows the emergency stop control process when an emergency stop switch is pushed. The flowchart which shows a working machine stop control process when a working machine stop switch is pushed. The side view which shows the hydraulic shovel concerning the modification of this invention.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[Description of the entire hydraulic excavator]
FIG. 1 shows a hydraulic excavator 1 as a work machine according to the present embodiment. The hydraulic excavator 1 is a large loading excavator used in a mine or the like, and includes a vehicle body 2 and a work implement 3.

[Vehicle body]
The vehicle main body 2 includes a traveling body 21 and a revolving body 22 as an upper revolving body provided on the traveling body 21 so as to be able to turn. The traveling body 21 includes a pair of left and right traveling devices 211. Each traveling device 211 includes a crawler belt 212 and drives the excavator 1 by driving the crawler belt 212 with a left traveling motor 213L and a right traveling motor 213R, which will be described later.

[Swivel body]
The swing body 22 includes a cab 23, a counterweight 24, and an engine room 25. The counterweight 24 is provided for weight balance with the work machine 3 and is filled with heavy objects.
The revolving structure 22 is revolved by a hydraulic revolving motor 26 described later. Further, the revolving structure 22 is also provided with a hydraulic lift ladder 27 for an operator to get on and off, and a service arm 28 (FIG. 7) provided with a fuel supply port. Details of the lifting ladder 27 and the service arm 28 will be described later.

[Work machine]
The work implement 3 is attached to the center of the front portion of the revolving structure 22 and includes a boom 31, an arm 32, a bucket 33, a boom cylinder 34, an arm cylinder 35, a bucket cylinder 36, and a crumb cylinder 37. A base end portion of the boom 31 is rotatably connected to the swing body 22.
Further, the base end portion of the arm 32 is rotatably connected to the distal end portion of the boom 31. A bucket 33 is rotatably connected to the tip of the arm 32. The bucket 33 is a bucket that can be opened and closed by a crumb cylinder 37 provided therein.

The boom cylinder 34, the arm cylinder 35, the bucket cylinder 36, and the crumb cylinder 37 are hydraulic cylinders that are driven by hydraulic oil discharged from a hydraulic pump 5 described later. The boom cylinder 34 operates the boom 31, and the arm cylinder 35 operates the arm 32. The bucket cylinder 36 operates the bucket 33, and the crumb cylinder 37 opens and closes the bucket 33.

[Configuration of hydraulic circuit of hydraulic excavator]
FIG. 2 shows the overall configuration of the hydraulic circuit of the excavator 1.
Since the hydraulic excavator 1 is a large loading excavator for mines, two boom cylinders 34, arm cylinders 35, bucket cylinders 36, and crumb cylinders 37, which are hydraulically driven working machines, are provided. .
Further, the turning motor 26, the left traveling motor 213L, and the right traveling motor 213R described above are driven by hydraulic pressure. Accordingly, the hydraulic drive apparatus of the present invention is constituted by the cylinders 34 to 37 and the motors 26, 213L, and 213R.

[Hydraulic pump]
The hydraulic excavator 1 includes four hydraulic pumps 5A, 5B, 5C, and 5D as hydraulic pumps 5 for driving the hydraulic drive device.
Each of the hydraulic pumps 5A, 5B, 5C, 5D is composed of two variable displacement hydraulic pumps connected in series to the drive shafts 6A, 6B, 6C, 6D. Each drive shaft 6A, 6B, 6C, 6D is driven by the output of an engine or an electric motor transmitted via a PTO (Power take-off) (not shown). The electric motor is driven by electric power of a generator that generates electricity with the output of the engine or electric power supplied via a cable from a generator installed outside the hydraulic excavator 1.
Further, the number of hydraulic pumps 5 and the number of engines and electric motors that drive the drive shafts of the hydraulic pump 5 may be set according to the size of the hydraulic excavator 1 and the like. For example, in the case of a hydraulic excavator having a larger capacity of the bucket 33, two or more engines and electric motors may be arranged. Three or more hydraulic pumps 5 may be connected in series to one drive shaft.

The hydraulic excavator 1 includes a hydraulic control valve (control valve) 50 for supplying hydraulic oil pumped from each hydraulic pump 5A, 5B, 5C, 5D to each hydraulic drive device. In the present embodiment, 3 to 4 hydraulic control valves 50 are provided for each of the hydraulic pumps 5A, 5B, 5C, and 5D, and a total of 14 hydraulic control valves 50A to 50N are provided. In the following description, when the features common to the hydraulic control valves 50A to 50N are described, the hydraulic control valves 50A to 50N are collectively referred to as the hydraulic control valve 50.

[Combination of hydraulic control valve and hydraulic drive device for hydraulic pump 5A]
Three hydraulic control valves 50A to 50C are connected to the hydraulic pump 5A. The hydraulic control valve 50 </ b> A controls the expansion and contraction of the arm cylinder 35. The hydraulic control valve 50B performs control for extending the bucket cylinder 36 (bucket dump control) and control for extending the boom cylinder 34 (boom-up control). The hydraulic control valve 50 </ b> C controls the driving of the turning motor 26.

[Combination of hydraulic control valve and hydraulic drive for hydraulic pump 5B]
Four hydraulic control valves 50D to 50G are connected to the hydraulic pump 5B. The hydraulic control valve 50D controls driving of the left traveling motor 213L. The hydraulic control valve 50E performs control to extend the arm cylinder 35 (arm dump control) and control to extend the bucket cylinder 36 (bucket dump control). The hydraulic control valve 50 </ b> F controls the expansion / contraction of the crumb cylinder 37. The hydraulic control valve 50G controls expansion and contraction of the boom cylinder 34.

[Combination of hydraulic control valve and hydraulic drive for hydraulic pump 5C]
Three hydraulic control valves 50H to 50J are connected to the hydraulic pump 5C. The hydraulic control valve 50H performs control (boom down control) for contracting the boom cylinder 34. The hydraulic control valve 50I controls expansion and contraction of the bucket cylinder 36. The hydraulic control valve 50J controls driving of the turning motor 26.

[Combination of hydraulic control valve and hydraulic drive for hydraulic pump 5D]
Four hydraulic control valves 50K to 50N are connected to the hydraulic pump 5D. The hydraulic control valve 50K controls driving of the right traveling motor 213R. The hydraulic control valve 50L controls the expansion and contraction of the arm cylinder 35. The hydraulic control valve 50M controls expansion and contraction of the bucket cylinder 36. The hydraulic control valve 50N controls expansion and contraction of the boom cylinder 34.

[Description of a plurality of hydraulic circuits corresponding to a hydraulic drive unit]
The hydraulic drive devices other than the crumb cylinder 37 and the traveling motors 213L and 213R are controlled by a plurality of hydraulic pumps 5A, 5B, 5C, 5D and a hydraulic control valve 50 as described below.
The driving for extending the boom cylinder 34 is controlled by three hydraulic circuits including the hydraulic pumps 5A, 5B, 5D and the hydraulic control valves 50B, 50G, 50N.
The driving for contracting the boom cylinder 34 is controlled by three hydraulic circuits including hydraulic pumps 5B, 5C, 5D and hydraulic control valves 50G, 50H, 50N.
The drive for extending the arm cylinder 35 is controlled by three hydraulic circuits including hydraulic pumps 5A, 5B, 5D and hydraulic control valves 50A, 50E, 50L.
The driving for contracting the arm cylinder 35 is controlled by two hydraulic circuits including hydraulic pumps 5A and 5D and hydraulic control valves 50A and 50L.
The drive for extending the bucket cylinder 36 is controlled by four hydraulic circuits including hydraulic pumps 5A, 5B, 5C, 5D and hydraulic control valves 50B, 50E, 50I, 50M.
The driving for contracting the bucket cylinder 36 is controlled by two hydraulic circuits including hydraulic pumps 5C and 5D and hydraulic control valves 50I and 50M.

By controlling the hydraulic drive device with a plurality of hydraulic circuits in this way, even if one of the hydraulic pumps 5 or the hydraulic control valve 50 stops due to a failure or the like, control is performed using a hydraulic circuit of another system. be able to. For this reason, since the boom cylinder 34, the arm cylinder 35, and the bucket cylinder 36, which are work machines, are driven by a plurality of hydraulic circuits, even if some of the hydraulic pumps 5 and the hydraulic control valves 50 break down, the work machines are moved. Thus, the bucket 33 can be put on the ground, and the excavator 1 can be returned to a stable posture. Particularly, the control for extending the boom cylinder 34 is controlled by three systems and the control for extending the bucket cylinder 36 is controlled by four systems, so that the bucket 33 can be moved until it reaches the ground.

The turning motor 26 is controlled by two hydraulic circuits including hydraulic pumps 5A and 5C and hydraulic control valves 50C and 50J. Since the swing motor 26 is controlled by two hydraulic circuits, the amount of hydraulic oil supplied can be increased to operate the swing motor 26 efficiently.
The crumb cylinder 37 and the traveling motors 213L and 213R may also be driven by a plurality of hydraulic circuits. By controlling with these plural hydraulic circuits, the operation of the hydraulic excavator 1 can be continued even if one hydraulic pump 5 or hydraulic control valve 50 breaks down.

[Configuration of hydraulic control valve]
The hydraulic control valve 50 (50A to 50N) includes a pilot-type direction switching valve 51 (51A to 51N), a proportional control valve 52 (52A to 52N) as a first control valve, and a direction switching valve as a second control valve. 53 (53A to 53N). In the following description, when the features common to the pilot type directional control valves 51A to 51N, the proportional control valves 52A to 52N, and the directional control valves 53A to 53N are described, these are collectively referred to as the pilot type directional control valves. 51, a proportional control valve 52, and a direction switching valve 53.

[Pilot type directional switching valve]
The pilot-type direction switching valve 51 is disposed between each hydraulic pump 5A, 5B, 5C, 5D and the hydraulic drive device. The pilot-type directional switching valve 51 is a three-position type switching valve that has a spool that is moved by a pilot pressure, and switches the flow of hydraulic oil by moving the spool to three positions of two switching positions and a neutral position. . Further, the spool of the pilot type direction switching valve 51 is returned to the neutral position by a spring or the like when a pilot pressure of a predetermined value or more is not applied. When the spool returns to the neutral position, the hydraulic oil is not supplied to the hydraulic drive device, and the hydraulic drive device stops.
The pilot hydraulic line provided with the pilot-type directional switching valve 51, the proportional control valve 52, and the directional switching valve 53 includes a pilot hydraulic cutoff valve that shuts off the pilot hydraulic line and a PPC lock lever that operates the pilot hydraulic cutoff valve. Have

[Proportional control valve and direction switching valve]
The proportional control valve 52 and the direction switching valve 53 control the hydraulic oil supplied from the pilot pump (not shown) to the pilot-type direction switching valve 51 and supply the hydraulic oil from the hydraulic pumps 5A, 5B, 5C, 5D to the hydraulic drive device. Control oil flow and oil volume.
[Proportional control valve]
The proportional control valve 52 is an electromagnetic proportional valve and is controlled by a master controller 81 described later. The proportional control valve 52 controls the pilot pressure applied to the pilot-type direction switching valve 51.

[Direction switching valve]
The direction switching valve 53 is an electromagnetic direction switching valve and is controlled by slave controllers 82 and 83 to be described later. The direction switching valve 53 controls the moving direction of the spool of the pilot type direction switching valve 51.

[Hydraulic control valve operation]
The hydraulic control valve 50 operates with hydraulic oil supplied from a pilot pump (not shown). The hydraulic pump 5 may be used as a pilot pump.
The hydraulic oil supplied from the pilot pump is supplied to the proportional control valve 52. Then, the master controller 81 controls the proportional control valve 52 to adjust the flow rate of the hydraulic oil. The hydraulic oil whose flow rate is adjusted by the proportional control valve 52 is supplied to the direction switching valve 53. Therefore, if the master controller 81 restricts the flow rate of the proportional control valve 52, the flow rate of the hydraulic oil supplied to the direction switching valve 53 can be suppressed.
The slave controllers 82 and 83 control the direction switching valve 53 to switch the hydraulic oil supply destination. That is, when the hydraulic oil supplied from the proportional control valve 52 is supplied to the left operation unit 511 of the pilot-type direction switching valve 51 (see FIG. 3) by the direction switching valve 53, the right-side operation of the pilot-type direction switching valve 51 is performed. The hydraulic oil is discharged from the portion 512, and the spool of the pilot-type direction switching valve 51 moves to the right.
On the other hand, when the hydraulic oil supplied from the proportional control valve 52 is supplied to the operation unit 512 on the right side of the pilot-type direction switching valve 51 by the direction switching valve 53, the hydraulic oil is supplied from the operation unit 511 on the left side of the pilot-type direction switching valve 51. Is discharged, and the spool of the pilot-type directional control valve 51 moves to the left.
As described above, the hydraulic control valve 50 supplies hydraulic oil from the pilot pump to the pilot-type direction switching valve 51 via the proportional control valve 52 and the direction switching valve 53, and controls the movement of the spool of the pilot-type direction switching valve 51. As a result, the flow and amount of hydraulic oil supplied from the hydraulic pumps 5A, 5B, 5C, and 5D to the hydraulic drive device are controlled.

[Hydraulic cylinder]
Each of the cylinders 34 to 37 is configured by a general hydraulic cylinder. That is, the cylinders 34 to 37 include a cylinder tube and a piston rod. The inside of the cylinder tube is divided into two chambers on the cap side and the rod side by the piston portion of the piston rod.
When the cylinders 34 to 37 are extended, the hydraulic oil is supplied to the cap side, which is the base end side of the cylinder, in the two chambers, and the hydraulic oil is discharged from the rod side where the piston rod is provided.
When the cylinders 34 to 37 are contracted, the hydraulic oil is supplied to the rod side of the two chambers, and the hydraulic oil is discharged from the cap side.

[Operation control system]
Next, an operation control system for controlling the operation of the hydraulic drive device will be described with reference to FIGS. FIG. 3 illustrates the control of the hydraulic control valves 50A to 50C that control the hydraulic oil supplied from the hydraulic pump 5A.
As illustrated in FIG. 3, the operation control system includes a first operation signal output device 71 and a second operation signal output device 72 that detect an operation amount of the operation tool 60 and output an operation signal, a pump controller 80, and a master. A controller 81, slave controllers 82 and 83, an electric controller 84, and a monitor 85 are provided. The pump controller 80, master controller 81, slave controllers 82 and 83, electric controller 84, and monitor 85 are connected to each other via a CAN (Controller Area Network) 90. As described above, the master controller 81 and the slave controllers 82 and 83 are valve controllers that control the proportional control valve 52 and the direction switching valve 53.

[Operation tool]
As shown in FIG. 4, the operating tool 60 of the present embodiment includes a right lever 61, a left lever 62, a right pedal 63 that commands driving of the right traveling device, a left pedal 64 that commands driving of the left traveling device, and a crumb open. A pedal 65, a clam close pedal 66, and a turning brake pedal 67 are provided. The right lever 61, the left lever 62, the right pedal 63, and the left pedal 64 operate the driving of the boom cylinder 34, the arm cylinder 35, the bucket cylinder 36, the turning motor 26, the right traveling motor 213R, and the left traveling motor 213L. The clam open pedal 65 and the clam close pedal 66 operate the driving of the clam cylinder 37. The turning brake pedal 67 performs a brake operation of the turning motor 26. The number of hydraulic control valves 50 can be arbitrarily set. Further, the turning motor 26 may be driven and braked only by the turning lever (the left lever 62 in this embodiment) without providing the turning brake pedal 67. That is, the turning lever and the turning brake pedal may be shared by one lever.

[Lever operation pattern]
The operation pattern of the right lever 61 and the left lever 62 in the excavator 1 of the present embodiment is as follows. The front / rear operation of the right lever 61 is a boom lowering / raising operation, and the right / left operation of the right lever 61 is a bucket excavating / dumping operation. The front / rear operation of the left lever 62 is an arm dump / excavation operation, and the left / right operation of the left lever 62 is a left turn / right turn operation.

[First operation signal output device and second operation signal output device]
The first operation signal output device 71 and the second operation signal output device 72 are sensors for detecting the operation amount of the operation tool 60, and are provided for each operation tool 60 as shown in FIG.
The right lever 61 is provided with first operation signal output devices 71LRA and 71FRA and second operation signal output devices 72LRA and 72FRA, and outputs signals corresponding to the front and rear operations and the left and right operations of the right lever 61.
The first operation signal output device 71LRA and the second operation signal output device 72LRA detect the left and right operations of the right lever 61 and output operation signals corresponding to the left and right operations.
The first operation signal output device 71FRA and the second operation signal output device 72FRA detect the operation before and after the right lever 61 and output an operation signal corresponding to the operation before and after.
The left lever 62 is provided with first operation signal output devices 71LRB and 71FRB and second operation signal output devices 72LRB and 72FRB, and outputs signals corresponding to the front and rear operations and the left and right operations of the left lever 62.
The first operation signal output device 71LRB and the second operation signal output device 72LRB detect left and right operations of the left lever 62 and output operation signals corresponding to the left and right operations.
The first operation signal output device 71FRB and the second operation signal output device 72FRB detect the operation before and after the left lever 62 and output an operation signal corresponding to the operation before and after.
The right pedal 63 is provided with a first operation signal output device 71C and a second operation signal output device 72C, and the left pedal 64 is provided with a first operation signal output device 71D and a second operation signal output device 72D. The first operation signal output device 71C and the second operation signal output device 72C detect the operation of the right pedal 63 and output an operation signal corresponding to the pedal operation. The first operation signal output device 71D and the second operation signal output device 72D detect the operation of the left pedal 64 and output an operation signal corresponding to the pedal operation.
The clam open pedal 65 is provided with a first operation signal output device 71E and a second operation signal output device 72E, and the clam close pedal 66 is provided with a first operation signal output device 71F and a second operation signal output device 72F. The turning brake pedal 67 is provided with a first operation signal output device 71G and a second operation signal output device 72G. The first operation signal output device 71E and the second operation signal output device 72E detect the operation of the crumb open pedal 65 and output an operation signal corresponding to the pedal operation. The first operation signal output device 71F and the second operation signal output device 72F detect the operation of the clam close pedal 66 and output an operation signal corresponding to the pedal operation. The first operation signal output device 71G and the second operation signal output device 72G detect the operation of the turning brake pedal 67 and output an operation signal corresponding to the pedal operation.

[Sensor for operation amount detection]
The first operation signal output device 71 and the second operation signal output device 72 include a sensor that detects an operation amount (a lever tilt angle or a pedal depression angle) of the operation tool 60, and an operation based on detection data of the sensor. Output a signal. If the operation tool 60 is an electric lever or pedal, a potentiometer or the like can be used as the sensor. Further, if the operation tool 60 is a pilot-type lever or the like, a pressure sensor or the like that detects a pilot pressure that is changed by the operation of the operation tool 60 and converts it into an electric signal can be used as the sensor.

[Operation signal]
Further, the operation signals output from the first operation signal output device 71 and the second operation signal output device 72 may be electrical signals whose voltage value is proportional to the operation amount, or digital data indicating the operation amount. When the operation signal output device outputs digital data, the data may be input to the master controller 81 or the slave controller 82 via the CAN 90.
In the present embodiment, the operation signals output from the first operation signal output device 71 and the second operation signal output device 72 are electrical signals having a voltage value proportional to the operation amount of the operation tool 60, as shown in FIG. Yes, and it is set so that voltage values inverted from each other are output.
That is, the first operation signal V1 output from the first operation signal output device 71 is 4V when the operation amount of the operation tool 60 is 100%, 1V when the operation amount is −100%, and the neutral position (operation amount). 0%) is set to 2.5V.
On the other hand, the second operation signal V2 output from the second operation signal output device 72 is 1V when the operation amount of the operation tool 60 is 100%, 4V when the operation amount is −100%, and the neutral position (operation amount). 0%), the voltage is 2.5 V, and is set to have a reverse characteristic to the first operation signal V1.

Since the first operation signal V1 and the second operation signal V2 have opposite characteristics, when the first operation signal V1 and the second operation signal V2 are added, a constant value (5V) is always obtained. Therefore, by detecting the voltage values of these two operation signals V1 and V2, it is possible to check the abnormality of each operation signal. In addition, even when noise affects the operation signals V1 and V2, since the influence of noise can be eliminated by adding the two operation signals V1 and V2, signal processing with high noise resistance becomes possible. The correct operation amount can be grasped from the operation signal.
An operation signal may be input from the operation tool 60 to the master controller 81 or the slave controller 82 via the two CANs 90.

[Output signal output destination]
The first operation signal V1 output from the first operation signal output device 71 (71LRA, 71FRA, 71LRB, 71FRB, 71C to 71G) is input to the master controller 81.
The second operation signal V2 output from the second operation signal output device 72 (72LRA, 72FRA, 72LRB, 72FRB, 72C to 72G) is branched halfway and input to the master controller 81 and the slave controller 82.
Since the first operation signal V1 is input to the master controller 81 without branching, the wire harness can be reduced in turn as compared with the case where the second operation signal V2 is branched, and disconnection, short circuit, etc. The risk of failure can be reduced. For this reason, the master controller 81 can reduce the possibility that both the first operation signal V1 and the second operation signal V2 cannot be input simultaneously. Therefore, when only the first operation signal V1 is input, if the master controller 81 is configured so that the operation amount can be determined only by the input first operation signal V1, the operation amount of the operation tool 60 cannot be detected. The rate can be reduced.

Next, in the hydraulic excavator 1, the elevating ladder 27 and the service arm 28 provided as hydraulic drive devices other than the work machine 3, the turning motor 26, and the traveling motors 213L and 213R will be described.
[Elevator ladder]
As shown in FIG. 6, the elevating ladder 27 is disposed on the left side of the revolving structure 22. The elevator ladder 27 is raised and lowered by a ladder hydraulic cylinder (not shown in FIG. 6). The lifting ladder 27 is used for getting on and off by an operator, and is stored in the vehicle body 2 when the excavator 1 is in operation. The ladder hydraulic cylinder is provided in the revolving structure 22 and when the ladder hydraulic cylinder is extended, the elevator ladder 27 rotates upward about the rotation shaft on the upper end side thereof, and is stored as indicated by a two-dot chain line in FIG. Stored in position.
On the other hand, when the rudder hydraulic cylinder is contracted, the elevating ladder 27 rotates downward about the rotation axis on the upper end side, and is disposed at the use position indicated by the solid line in FIG.

[Service Arm]
The service arm 28 is provided with a drain / replenishment port for fuel, fat and oil, and cooling water, and is disposed on the lower surface of the revolving structure 22 as shown in FIG. The service arm 28 is moved up and down by a service arm hydraulic cylinder (not shown in FIG. 7). That is, when the service arm hydraulic cylinder is extended, the service arm 28 pivots upward about the pivot shaft on the base end side and is stored in the retracted position indicated by the two-dot chain line in FIG.
On the other hand, when the service arm hydraulic cylinder 281 is contracted, the service arm 28 rotates downward and is disposed at a use position indicated by a solid line in FIG.

[Controller configuration]
Next, each controller provided in the excavator 1 will be described with reference to FIGS.
[Pump controller]
The pump controller 80 controls the entire hydraulic system. For this reason, the pump controller 80 controls the hydraulic pump 5 (5A to 5D), and also performs power supply control of the master controller 81 and slave controllers 82 and 83. Further, information from each controller is output to the monitor 85 via the CAN 90.

[Electric controller]
The electric controller 84 performs control related to the electric motor 100 that drives the hydraulic pump 5, specifically, detects a failure or the like, performs control for notifying the operator, and control of other electrical components.
When the hydraulic pump 5 is driven by an engine, the engine is controlled by the engine controller, and the electric controller 84 controls the electrical components.
As shown in FIG. 9, the electric motor 100 drives the drive shafts 6A, 6B, 6C, and 6D via the PTO.

[Hydraulic control valve controller]
In this embodiment, a master controller 81, a first slave controller 82, and a second slave controller 83 are provided as valve controllers for controlling the hydraulic control valve 50.

[Master controller]
The master controller 81 detects the operation amount of the operation tool 60 and generates a control signal for controlling the work implement, the turning motor 26, and the travel motors 213L and 213R, and proportional control of the hydraulic control valve 50 based on the control signal. The valve 52 is controlled. Further, the abnormality of the operation input system such as the operation tool 60 or the abnormality of the slave controller 82 is determined.
The master controller 81 includes devices other than the work machine 3 and the motors 26, 213L, and 213R, specifically, a ladder hydraulic cylinder 271 that drives the lifting ladder 27 and a service arm 28 as shown in FIG. The operation of the hydraulic cylinder 281 for the service arm that drives the motor is controlled.

The master controller 81 is a controller having a CPU (Central Processing Unit), and as shown in FIG. 8, a first input unit 811, a first determination unit 812, a control signal generation unit 813, a first control signal output unit 814, A first communication unit 815, a ladder control unit 816, and a service arm control unit 817 are provided.
The ladder control unit 816 controls the operation of the ladder hydraulic cylinder 271 and performs speed control when the elevator ladder 27 is lowered. Further, pressing control is performed so that the lifting ladder 27 does not fall during the shovel operation.
The service arm control unit 817 controls the operation of the service arm hydraulic cylinder 281 and controls the arm 32 to move up and down.

[First input section]
The first input unit 811 is an interface that receives operation signals output from the first operation signal output device 71 and the second operation signal output device 72 and outputs digital data corresponding to the input signals. In the present embodiment, the voltage value of the input operation signal is output to the first determination unit 812.

[First determination unit]
The first determination unit 812 checks the operation signal based on the first operation signal and the second operation signal input from the first input unit 811, and the second output from the slave controller 82 via the first communication unit 815. A check is performed by comparison with the manipulated variable data.
The first determination unit 812 detects whether the voltage value of the first operation signal and the voltage value of the second operation signal are equal to each other, and whether the two input operation signals are abnormal. Check. As described above, the first operation signal and the second operation signal have opposite characteristics, and when the voltage values of the two signals are added, they should always be a constant value (5 V). Therefore, the abnormality of each operation signal can be checked based on the voltage values of these two operation signals. The comparison check with the second manipulated variable data in the first determination unit 812 will be described later.

[Control signal generator]
The control signal generation unit 813 obtains the operation amount (first operation amount data) of the operation tool 60 from the relationship of FIG. 5 based on the voltage value V1 of the first operation signal input from the first input unit 811.
Further, the control signal generation unit 813 calculates a control amount of each hydraulic control valve 50 according to the first operation amount data, and generates a control signal based on the control amount. Specifically, the control signal generator 813 generates a first control signal that is an operation signal for controlling the proportional control valve 52 and a second control signal that is an operation signal for controlling the direction switching valve 53.

[First control signal output unit]
The first control signal output unit 814 outputs the first control signal generated by the control signal generation unit 813 to the proportional control valve 52 of the hydraulic control valve 50 to be driven. For example, when a control signal for driving the swing motor 26 is generated, the first control signal is output to the proportional control valves 52C and 52J of the hydraulic control valves 50C and 50J that drive the swing motor 26.

[First communication unit]
The first communication unit 815 outputs the first operation amount data and the second control signal generated by the control signal generation unit 813 to the slave controller 82 via the CAN 90. The first communication unit 815 outputs the second control signal to the slave controller 83 via the CAN 90.
Further, the first communication unit 815 receives second operation amount data (described later) output from the slave controller 82, and outputs the second operation amount data to the first determination unit 812.

[Operation amount data judgment]
The first determination unit 812 compares the input second operation amount data with the first operation amount data, and determines whether there is a match or not. For example, when an abnormality occurs in the slave controller 82, the second manipulated variable data output from the slave controller 82 is not correctly updated. For this reason, if the first operation amount data is changed by operating the operation tool 60, the first operation amount data does not match with the second operation amount data that is not updated. Therefore, the first determination unit 812 indicates that an abnormality has occurred in the slave controller 82. It can be detected.

[First slave controller]
The slave controller 82 controls the direction switching valve 53 of the hydraulic control valve 50 based on the second control signal generated by the master controller 81. In this embodiment, two slave controllers 82 and 83 are provided, and the first slave controller 82 controls the direction switching valves 53A to 53G of the hydraulic control valves 50A to 50G. Also, abnormality of the master controller 81 is determined.

Similarly to the master controller 81, the slave controller 82 is a controller having a CPU (Central Processing Unit). However, the slave controller 82 does not have the configuration corresponding to the control signal generation unit 813 because the first operation signal V1 is not input. Therefore, the slave controller 82 includes a second input unit 821, a second determination unit 822, a second control signal output unit 823, and a second communication unit 824, as shown in FIG.

[Second input section]
The second input unit 821 is an interface that receives the second operation signal output from the second operation signal output device 72 and outputs digital data corresponding to the input signal. In the present embodiment, the voltage value of the input second operation signal is output to the second determination unit 822.

[Second determination unit]
The second determination unit 822 obtains second operation amount data from the relationship of FIG. 5 based on the voltage value V2 of the second operation signal input from the second input unit 821, and the second operation amount data and the master The first operation amount data input from the controller 81 via the CAN 90 and the second communication unit 824 is compared. Then, the second determination unit 822 determines that the first operation amount data and the second operation amount data match, and determines that it is normal, and if they do not match, determines that the master controller 81 or the like is abnormal.

[Second control signal output unit]
The second control signal output unit 823 outputs the second control signal input from the master controller 81 via the CAN 90 and the second communication unit 824 to the direction switching valve 53 of the hydraulic control valve 50 to be controlled. For example, when the control signal for driving the swing motor 26 is generated by the control signal generator 813, the hydraulic control valve 50C, 50J for driving the swing motor 26 is the second one with respect to the direction switching valve 53C of the hydraulic control valve 50C. 2 Outputs a control signal. The slave controller 83 controls the hydraulic control valve 50J.

[Second communication section]
The second communication unit 824 outputs the second manipulated variable data to the master controller 81 via the CAN 90. Further, the first operation amount data and the second control signal output from the master controller 81 are input.

[Second slave controller]
The second slave controller 83 controls the direction switching valve 53 of the hydraulic control valve 50 based on the second control signal generated by the master controller 81. The second slave controller 83 controls the direction switching valves 53H to 53N of the hydraulic control valves 50H to 50N.

The slave controller 83 is also a controller having a CPU (Central Processing Unit), and includes a second control signal output unit 831 and a third communication unit 832 as shown in FIG.

[Second control signal output unit]
The second control signal output unit 831 outputs the second control signal input from the master controller 81 via the CAN 90 and the third communication unit 832 to the direction switching valve 53 of the hydraulic control valve 50 to be controlled. For example, when a control signal for driving the swing motor 26 is generated by the control signal generator 813, the hydraulic control valve 50C, 50J for driving the swing motor 26 is the second of the direction switching valve 53J of the hydraulic control valve 50J. 2 Outputs a control signal.
[Third communication section]
The third communication unit 832 receives the second control signal output from the master controller 81.

[Emergency stop system]
Next, an emergency stop system in the hydraulic excavator 1 will be described with reference to FIG.
The excavator 1 includes a battery 40 and an ACC power source (accessory power source) 44 as power sources. A power supply line 401 that supplies power from the battery 40 is connected to the pump controller 80, the electric controller 84, and the monitor 85. Accordingly, the pump controller 80, the electric controller 84, and the monitor 85 are operated with the power of the battery 40.
The ACC power supply 44 is a power supply that supplies power when the ignition switch of the excavator 1 is turned on and does not supply power in the off state. The ACC power supply 44 starts power supply to the pump controller 80 when the ignition switch is turned on.
An emergency stop switch 45 and a work implement stop switch 46 are connected to the ACC power supply 44.

[Relay connection]
The power supply line 401 is connected to a contact of the first relay 41 described later and a contact of the second control relay 102. The contact of the first relay 41 is connected to one contact of the second relay 42, and the other contact of the second relay 42 is connected to the master controller 81 and the contact of the third relay 43.
The contact of the third relay 43 is connected to the slave controllers 82 and 83.

The contact of the second control relay 102 is connected to an electromagnetic coil of the third control relay 103 described later. The electric motor input power source 104 and the electric motor 100 are connected to the contacts of the third control relay 103.

The ACC power supply 44 is connected to the electromagnetic coil of the first relay 41 and one contact of the first control relay 101 via a plurality of emergency stop switches 45. The other contact of the first control relay 101 is connected to the electromagnetic coil of the second control relay 102.
The ACC power supply 44 is connected to the electromagnetic coil of the third relay 43 via a plurality of work implement stop switches 46. The ACC power supply 44 is connected to the pump controller 80 to supply power.
The pump controller 80 is connected to the electromagnetic coil of the first control relay 101 and the electromagnetic coil of the second relay 42.

[Relay arrangement in the power supply line]
As shown in FIG. 9, contacts of the first relay 41, the second relay 42, and the third relay 43 are connected to the power supply line 401 in series. That is, the contacts of the first relay 41, the second relay 42, and the third relay 43 are sequentially connected to the battery 40 that is a power source from the upstream side.
The electromagnetic coils of the relays 41, 42, 43 are connected to the emergency stop switch 45, the pump controller 80, and the work implement stop switch 46.
Therefore, when only the third relay 43 is disconnected by operating the work implement stop switch 46, the power supply to the slave controllers 82 and 83 connected to the downstream side of the third relay 43 is disconnected.
Further, when the first relay 41 is disconnected by the operation of the emergency stop switch 45, or when the second relay 42 is disconnected by the control of the pump controller 80, the first relay 41 and the second relay 42 are arranged downstream. The power supply to the master controller 81 and slave controllers 82 and 83 to be connected is cut off.

[Relay structure]
The 1st relay 41, the 2nd relay 42, and the 3rd relay 43 are comprised by the general electromagnetic relay. That is, each of the relays 41 to 43 includes contacts of a C terminal (Common terminal), a NO terminal (Normally Open terminal), and an NC terminal (Normally Closed terminal), a contact piece connecting the C terminal and the NO terminal or NC terminal, An electromagnetic coil (electromagnet) for moving the contact piece is provided. In the relays 41 to 43, when a current flows through the electromagnetic coil, the contact piece conducts the C terminal and the NO terminal, and when no current flows through the electromagnetic coil, the contact piece separates from the NO terminal. Therefore, by connecting the C terminal and the NO terminal to the power supply line 401, the power supply line 401 is conducted when a current flows through each electromagnetic coil, and the power supply line when a current does not flow through the electromagnetic coil. Block 401.

[Emergency stop switch]
A plurality of emergency stop switches 45 are provided, and are arranged in a place where an operator who is performing maintenance work can operate, such as the cab 23 of the excavator 1, the lifting ladder 27, and the service arm 28.
The plurality of emergency stop switches 45 are connected in series to the ACC power supply 44. When all the emergency stop switches 45 are in the non-input state (normal state), the emergency stop switch 45 maintains a conductive state in which power from the ACC power supply 44 can be supplied. On the other hand, in an emergency state in which even one emergency stop switch 45 is pressed to perform an input operation, the emergency stop switch 45 cuts off power from the ACC power supply 44 to the electromagnetic coil of the first relay 41.

[Work machine stop switch]
The work machine stop switch 46 is a switch that is pressed when the work machine 3 needs to be stopped. Specifically, the work implement stop switch 46 is input when the switch provided near the elevator ladder 27, the switch provided near the service arm 28, and the PPC lock lever provided on the cab 23 are locked. And a switch. Further, a switch for stopping only the work machine may be provided at an appropriate place.
The plurality of work implement stop switches 46 are connected in series to the ACC power supply 44. When all the work machine stop switches 46 are in the non-input state, the work machine stop switch 46 maintains a conduction state in which power from the ACC power supply 44 can be supplied. On the other hand, when at least one work implement stop switch 46 is pressed and inputted, the work implement stop switch 46 cuts off the power from the ACC power supply 44 to the electromagnetic coil of the third relay 43.

[Electric motor operation circuit]
In order to operate the electric motor 100, the first control relay 101, the second control relay 102, and the third control relay 103 described above are provided.
The contact of the first control relay 101 is connected to the most downstream terminal of the plurality of emergency stop switches 45 connected in series and the electromagnetic coil of the relay 41, and the electromagnetic coil is connected to the pump controller 80. For this reason, the contact of the first control relay 101 is opened and closed by outputting a control signal from the pump controller 80 to the electromagnetic coil.
The contact of the second control relay 102 is connected to the battery 40, and the electromagnetic coil is connected to the contact of the first control relay 101. For this reason, the contact of the second control relay 102 is opened and closed by connecting and disconnecting the contact of the first control relay 101.
The contact point of the third control relay 103 is connected to the electric motor input power source 104, and the electromagnetic coil is connected to the contact point of the second control relay 102. Therefore, the contact of the third control relay 103 is opened and closed by connecting and disconnecting the contact of the second control relay 102.

[Operation control processing]
Next, control processing when the operator operates the operation tool 60 will be described with reference to the flowchart of FIG.
When the first operation signal and the second operation signal corresponding to the state of the operation tool 60 are output from the first operation signal output device 71 and the second operation signal output device 72, the master controller 81 and the slave controller 82 are shown in the flowchart of FIG. The operation control process shown is executed.
The master controller 81, which is the first control device, inputs a first operation signal (step S1). The slave controller 82 as the second control device inputs the second operation signal (step S11).

After the input of the first operation signal, the master controller 81 outputs the first operation amount data based on the first operation signal to the slave controller 82 as the second control device via the CAN 90 (step S2).
Similarly, after inputting the second operation signal, the slave controller 82 outputs second operation amount data based on the second operation signal to the master controller 81 as the first control device via the CAN 90 (step S12).

The master controller 81 inputs the second operation amount data output from the slave controller 82 (step S3), and the first determination unit 812 compares the first operation amount data and the second operation amount data (step S4). It is determined whether it is abnormal (step S5).
Similarly, the slave controller 82 inputs the first operation amount data output from the master controller 81 (step S13), and the second determination unit 822 compares the first operation amount data and the second operation amount data (step S13). S14), it is determined whether it is abnormal (step S15).

[Processing during normal judgment]
When the master controller 81 determines that the determination result in step S5 is normal (No), the master controller 81 generates a control signal (a first control signal and a second control signal) from the two input operation signals. That is, the master controller 81 receives a first operation signal from the first operation signal output device 71 and a second operation signal from the second operation signal output device 72. Therefore, the master controller 81 generates a first control signal for operating the proportional control valve 52 and a second control signal for operating the direction switching valve 53 from these two operation signals.
Then, the master controller 81 outputs a first control signal from the first control signal output unit 814 (step S6), and controls the proportional control valve 52 of the hydraulic control valve 50 (step S7). The master controller 81 outputs a second control signal to the slave controllers 82 and 83 via the CAN 90. The slave controller 82 may generate a second control signal for operating the direction switching valve 53 and output the second control signal to the slave controller 83 via the CAN 90.

The second control signal output units 823 and 831 of the slave controllers 82 and 83 output the second control signal input from the master controller 81 when determined to be normal (No) in step S15 (step S16), and the hydraulic pressure The direction switching valve 53 of the control valve 50 is controlled (step S17).
The pilot type directional control valve 51 operates when both the proportional control valve 52 and the directional control valve 53 are normally controlled. Then, hydraulic oil is supplied to the hydraulic drive device to be driven, and the excavator 1 operates according to the operation of the operation tool 60.
The master controller 81 and the slave controller 82 end the operation control process shown in FIG. 10 after outputting the first control signal and the second control signal.
Therefore, when the signal from the operation tool 60 is continuously input, the operation control process of FIG. 10 is also continuously executed.

In this embodiment, since two slave controllers 82 and 83 are provided and the direction switching valve 53 controlled by each slave controller 82 and 83 is divided, a CPU abnormality occurs in one slave controller 82 and 83. Even so, the direction switching valve 53 managed by the other normal slave controllers 82 and 83 can operate normally. As described above, the boom cylinder 34, the arm cylinder 35, the bucket cylinder 36, and the turning motor 26 are either one of the hydraulic control valves 50 A to 50 G controlled by the slave controller 82 and the hydraulic control controlled by the slave controller 83. It is controlled by any two or more of valves 50H to 50N. Therefore, even if an abnormality occurs in one of the slave controllers 82 and 83, if the other slave controller 82, 83 and the master controller 81 are normal, the cylinders 34 to 36, the turning motor 26, the traveling motors 213L, 213R It is also possible to continue driving. For example, when an abnormality occurs in the first slave controller 82, the driving of the turning motor 26 and the left traveling motor 213L may be continued. Similarly, when an abnormality occurs in the second slave controller 83, the driving of the turning motor 26 and the right traveling motor 213R may be continued.

[Processing when an error is detected]
Next, the control when the first determination unit 812 of the master controller 81 and the second determination unit 822 of the first slave controller 82 determine an abnormality (Yes in steps S5 and S15) will be described.
[When master controller 81 determines abnormality]
As described above, the first determination unit 812 of the master controller 81 determines that there is an abnormality.
(1) When it is determined that there is an abnormality by checking the first operation signal and the second operation signal input to the first input unit 811;
(2) If the first operation amount data detected by the first determination unit 812 and the second operation amount data input from the slave controller 82 do not match, the first determination unit 812 of the master controller 81 is abnormal ( In step S5, Yes) is determined.
(3) The first determination unit 812 is also abnormal when the signal line input to the master controller 81 or the signal line output from the master controller 81 to the proportional control valve 52 is short-circuited or disconnected (Yes in step S5). Is determined.

[Abnormal stop control by master controller 81]
The master controller 81 determines that an abnormality has occurred in any of the above cases (Yes in step S5), and the first control signal (stop signal) controls the proportional control valve 52 to the stop state by the first control signal output unit 814. Is output (step S8). Then, the proportional control valve 52 is controlled to be stopped (step S9). At this time, since each proportional control valve 52 suppresses the flow rate of the hydraulic oil, the pilot pressure applied to the pilot-type direction switching valve 51 is reduced regardless of the operation state of the direction switching valve 53. For this reason, the spool of the pilot direction switching valve 51 moves to the neutral position, and hydraulic fluid is not supplied via the pilot type direction switching valve 51. For this reason, the operation | movement of the working machine 3 and the traveling body 21 which are actuated by the boom cylinder 34, the arm cylinder 35, the bucket cylinder 36, the crumb cylinder 37, the turning motor 26, the traveling motors 213L and 213R is interrupted.

[When slave controller 82 determines abnormality]
As described above, the second determination unit 822 of the slave controller 82 determines that the second operation amount data detected by the second determination unit 822 and the first operation amount data input from the master controller 81 are abnormal. This is the case when they do not match. Similarly, the second determination unit 822 determines that the signal line input to the slave controller 82 or the signal line output from the slave controllers 82 and 83 to the direction switching valve 53 is abnormal.

[Abnormal stop control by slave controller 82]
If the slave controller 82 determines that an abnormality has occurred (Yes in step S15), the second control signal output unit 823 outputs a second control signal (stop signal) for controlling the direction switching valve 53 to be stopped (step S15). S18). Furthermore, the slave controller 82 instructs the slave controller 83 to control the direction switching valve 53 to the stop state via the CAN 90 and the second communication unit 824. Therefore, the slave controller 83 outputs a second control signal (stop signal) for controlling the direction switching valve 53 to the stop state by the second control signal output unit 831 (step S18).
Then, the direction switching valve 53 is controlled to be stopped (step S19). At this time, each directional control valve 53 is controlled so that the spool moves to the neutral position and the hydraulic oil does not flow to the pilot directional control valve 51. Therefore, regardless of the operating state of the proportional control valve 52, the pilot type The pilot pressure applied to the direction switching valve 51 decreases. For this reason, the spool of the pilot type directional switching valve 51 moves to the neutral position, and hydraulic oil is not supplied via the pilot type directional switching valve 51. Therefore, the boom cylinder 34, the arm cylinder 35, the bucket cylinder 36, the crumb cylinder 37, The operations of the work machine 3 and the traveling body 21 that are operated by the turning motor 26 and the traveling motors 213L and 213R are interrupted. However, when there is hydraulic oil supply from another control valve, the operation of the work machine 3 and the traveling body 21 can be continued.

In this way, the proportional control valve 52 and the direction switching valve 53 which are two valves for operating the pilot-type direction switching valve 51 are controlled by separate controllers of the master controller 81 and the slave controllers 82 and 83. Therefore, not only when an abnormality occurs in the sensor that detects the operation amount of the operation tool 60, or when an abnormality such as disconnection occurs in the input line of the operation signal, one CPU of the master controller 81 or the slave controller 82 Even if an abnormality occurs, the pilot-type directional control valve 51 can be controlled to be stopped by stopping at least one of the proportional control valve 52 and the directional switching valve 53, and a hydraulic drive device such as a work machine or a travel motor can be controlled. Can be safely stopped. Therefore, the safety of the hydraulic excavator 1 can be further improved.

[Electric motor start control]
Next, start control of the electric motor 100 in the hydraulic excavator 1 will be described with reference to FIG.
When the ignition key of the hydraulic excavator 1 is turned on, the voltage of the line from the ACC 44 to the relay 41 (43, 101) changes.
Then, electric power is supplied from the ACC power supply 44 via the emergency stop switch 45. The pump controller 80 receives the signal output from the C terminal of the starter 110 when the ignition key is turned on, or detects the start of power supply from the ACC power supply 44 based on a change in voltage level or the like. A control signal (current) for instructing connection of the first control relay 101 to the electromagnetic coil of the relay 101 is output. The first control relay 101 is connected by a control signal from the pump controller 80 because the contact is opened when no current flows through the electromagnetic coil and is connected when the current flows.

When the contact of the first control relay 101 is connected, the power supplied from the ACC power supply 44 flows to the electromagnetic coil of the second control relay 102, and the contact of the second control relay 102 is connected.
When the contact of the second control relay 102 is connected, the power supplied from the battery 40 flows to the electromagnetic coil of the third control relay 103. Similarly to the first control relay 101 and the like, the third control relay 103 is connected in conjunction with the connection of the contact of the second control relay 102 because the contact is connected when a current flows through the electromagnetic coil.

When the contact of the third control relay 103 is connected, electric power is supplied from the electric motor input power source 104 to the electric motor 100, and the electric motor 100 is started. When the electric motor 100 is started, the drive shafts 6A, 6B, 6C, 6D are driven via the PTO, and the hydraulic pumps 5A, 5B, 5C, 5D are also operated.

[Control processing of emergency stop operation]
Next, with reference to the flowchart of FIG. 11, a control process when the operator performs an emergency stop operation by pressing the emergency stop switch 45 will be described.
Until the emergency stop switch 45 is pressed when the electric motor 100 is operating, it is determined No in step S31, so that emergency stop control is not executed. On the other hand, when the emergency stop switch 45 is pressed, Yes is determined in step S31, a part of the emergency stop switch 45 connected in series is disconnected, and the power supply from the ACC power supply 44 is stopped (step S31). S32).
By stopping the power supply from the ACC power supply 44 in step S32, emergency stop control of the electric motor (steps S33 to S35), emergency stop control of the valve controller by mechanical relay disconnection (steps S36 to S38), pump controller The emergency stop control (steps S39 → S37 → S38) of the valve controller by the control 80 is executed in parallel.

[Electric motor emergency stop control]
When the power supply from the ACC power supply 44 is stopped in step S32, the current supply flowing to the electromagnetic coil of the second control relay 102 via the first control relay 101 is also stopped, so that the second control relay 102 is disconnected. (Step S33).
The operation of the emergency stop switch 45 can be detected by the pump controller 80 that the power supply from the ACC power supply 44 is stopped, and the first control relay 101 can be disconnected by a control signal output from the pump controller 80. Also in this case, the second control relay 102 is disconnected.

When the second control relay 102 is disconnected, the current flowing through the electromagnetic coil of the third control relay 103 is also stopped, so the third control relay 103 is also disconnected (step S34). For this reason, the electric power supplied from the electric motor input power source 104 to the electric motor 100 is also stopped, and the electric motor 100 is stopped (step S35). For this reason, the hydraulic pumps 5A, 5B, 5C, 5D are also stopped (step S35).

[Emergency stop control of valve controller by mechanical relay disconnection]
When the emergency stop switch 45 is pressed and the power supply from the ACC power supply 44 is stopped in step S32, the current supply to the electromagnetic coil of the first relay 41 is also stopped and the first relay 41 is disconnected (step S36). That is, the first relay 41 is mechanically disconnected in conjunction with the operation of the emergency stop switch 45.
For this reason, the power supply from the battery 40 to the master controller 81 and the slave controllers 82 and 83 is also stopped, and the master controller 81 and the slave controllers 82 and 83 are no longer supplied with power and stop operating (step S37).
That is, the first relay 41 is disconnected in conjunction with the pressing of the emergency stop switch 45 and is not affected by the control from the controller. Therefore, even if an abnormality has occurred in the pump controller 80 or the like, if any one of the emergency stop switches 45 is pressed, the first relay 41 is controlled to be disconnected, and the master controller 81 or the slave controller The power supply to 82 and 83 can be stopped.
When the power supply to each of the controllers 81 to 83 is stopped, the output of control signals to the proportional control valve 52 and the direction switching valve 53 is also stopped, and as described above, the spool of each hydraulic control valve 50 moves to the neutral position. Since the supply of hydraulic oil stops, the work machine 3, the turning motor 26, and the travel motors 213L and 213R can be stopped (step S38).

[Emergency stop control of valve controller by control of pump controller 80]
When the emergency stop switch 45 is pressed and the pump controller 80 detects that the power supply from the ACC power supply 44 is stopped in step S32, the pump controller 80 outputs a control signal to the second relay 42, and the second relay 42 Is disconnected (step S39).
For this reason, the power supply from the battery 40 to the master controller 81 and the slave controllers 82 and 83 is also stopped, and the master controller 81 and the slave controllers 82 and 83 are no longer supplied with power and stop operating (step S37).
That is, the second relay 42 is controlled by the pump controller 80 that detects that the emergency stop switch 45 has been pressed. For this reason, even if the first relay 41 fails, if any one of the emergency stop switches 45 is pressed, the second relay 42 is controlled to be disconnected, and the master controller 81 and the slave controllers 82 and 83 are controlled. Power supply to can be stopped.
When the power supply to each of the controllers 81 to 83 is stopped, the output of control signals to the proportional control valve 52 and the direction switching valve 53 is also stopped, and as described above, the spool of each hydraulic control valve 50 moves to the neutral position. Since the supply of hydraulic oil is stopped, the work machine 3 and the like can be stopped (step S38).

Therefore, when the emergency stop switch 45 is pressed, the relay that cuts off the power supply to the master controller 81 and the slave controllers 82 and 83 is duplicated by the first relay 41 and the second relay 42 connected in series. Even if one of them fails and cannot be disconnected, the other can be shut off, so that each of the controllers 81 to 83 can be reliably stopped during an emergency stop. Therefore, as described above, since the spool of each hydraulic control valve 50 moves to the neutral position and the supply of hydraulic oil stops, the work implement 3 and the like can be stopped (step S38).
Further, since the control signal to the ladder hydraulic cylinder 271 and the service arm hydraulic cylinder 281 is also stopped, the raising / lowering of the lifting ladder 27 and the service arm 28 can also be stopped (step S38).
In addition, as described above, since the electric motor 100 is also stopped and the hydraulic pump 5 is also stopped, the hydraulic drive device driven by hydraulic pressure such as the work machine 3 can be stopped.
In this way, by pressing the emergency stop switch 45, the hydraulic excavator 1 can be stopped, collision with other construction machines and the like can be prevented, and safety can be improved.

The second relay 42 is controlled to be connected when a control signal is output from the pump controller 80. For this reason, when an abnormality occurs in the CPU of the pump controller 80, the control signal from the pump controller 80 stops, so the second relay 42 can be disconnected and the power supply to each of the controllers 81 to 83 is stopped. it can. Therefore, even if an abnormality occurs in the pump controller 80, the excavator 1 can be stopped reliably and safety can be improved.
Further, since the second relay 42 is controlled by the pump controller 80, the sensor data for detecting the operation state of the engine, the electric motor 100, the work machine 3, etc., as well as the case where the emergency stop switch 45 is pushed. From the above, it is possible to incorporate a program (logic) for determining whether an emergency stop operation is necessary in the pump controller 80 and stop the second relay 42 based on the determination result.

[Control by work implement stop switch input]
Next, control when the work implement stop switch 46 is pressed and input will be described with reference to the flowchart of FIG.
The work machine stop switch 46 operates when (1) when the lifting ladder 27 is lowered, (2) when the service arm 28 is lowered, (3) when the PPC lock lever is locked, or (4) when only other work machines are stopped. It is input by the user's operation. Accordingly, the work implement stop switch 46 may be disposed, for example, in the vicinity of the lifting ladder 27 that can confirm the lowered state of the lifting ladder 27 or in the vicinity of the service arm 28 that can confirm the lowered state of the service arm 28.

When the work implement stop switch 46 is pushed by the worker (Yes in step S41), the power supplied from the ACC power supply 44 does not flow to the electromagnetic coil of the third relay 43, and the third relay 43 is cut off. (Step S42). For this reason, the power supplied from the battery 40 via the first relay 41 and the second relay 42 does not flow to the slave controllers 82 and 83. That is, when the emergency stop switch 45 is pressed, the power supply to the controllers 81 to 83 is stopped, but when only the work implement stop switch 46 is pressed, the power supply to the master controller 81 is continued. (Step S43), only the power supply to the slave controllers 82 and 83 is stopped (Step S44).

For this reason, when the slave controllers 82 and 83 are stopped, the control signal to the direction switching valve 53 is not output, so that the spool of the hydraulic control valve 50 moves to the neutral position and the hydraulic pumps 5A, 5B, 5C, and 5D. The supply of hydraulic oil from stops. For this reason, the work machine 3 and the motors 26, 213L, and 213R are stopped (step S45).
On the other hand, since the master controller 81 is operating, the ladder hydraulic cylinder 271 and the service arm hydraulic cylinder 281 can operate (step S45). Accordingly, when the work implement stop switch 46 is pressed to stop because the elevator ladder 27 and the service arm 28 are forgotten to be stored, the elevator ladder 27 and the service arm 28 can be stored using the master controller 81. When the input of the work implement stop switch 46 is released and the third relay 43 returns to the connected state, the slave controllers 82 and 83 also return to the operating state, so that the work implement 3 and the motors 26, 213L, and 213R are also operated. become able to.

As described above, the master controller 81 and the slave controllers 82 and 83 constitute the work machine control device of the present invention in order to control the operation of the work machine 3. Moreover, since the pump controller 80 detects the operation of the emergency stop switch 45 and controls the second relay 42, it constitutes the second relay control device of the present invention.
In addition, the master controller 81 which is a work machine control device also controls driving of the lifting ladder 27 and the service arm 28 other than the work machine 3, and thus constitutes the first control device of the present invention.
Furthermore, the slave controllers 82 and 83 which are work implement control devices constitute the second control device of the present invention in order to control the drive of the work implement 3.

In addition to the emergency stop switch 45 and the work implement stop switch 46, the hydraulic excavator 1 may be provided with a switch for stopping the work implement 3 and the like during maintenance work of the hydraulic excavator 1. This maintenance switch is provided in a place where maintenance workers can easily operate.
When the maintenance switch is pressed, the electric motor 100 stops and the first relay 41 and the second relay 42 are disconnected and the controllers 81 to 83 are turned on as in the case where the emergency stop switch 45 is pressed. The power supply of is stopped.

It should be noted that the present invention is not limited to the above-described embodiments, and modifications, improvements, and the like within the scope that can achieve the object of the present invention are included in the present invention.
For example, the connection and disconnection of the third relay 43 are controlled by the input of the work implement stop switch 46, but may be controlled by a control signal from the pump controller 80 or the like, similar to the second relay 42. In this case, a logic for stopping only the work machine 3 can be set.

In the embodiment, the two slave controllers 82 and 83 are provided. However, only one slave controller may be provided, or three or more slave controllers may be provided. The number of slave controllers may be set according to the number of hydraulic control valves 50 and the like, and at least one slave controller that serves as the second control device may be provided.
Further, when the number of input / output signals to the master controller 81 increases, a plurality of master controllers 81 can be provided.
Furthermore, the work implement control device may be any device that can control at least the stop operation of the work implement 3, and if the work implement 3 can be stopped by one controller, the work implement control device may be configured only by that controller.

In the above embodiment, the proportional control valve 52 and the direction switching valve 53 are provided as the valves for operating the pilot type direction switching valve 51. However, for example, two proportional control valves 52 are provided and the pilot type direction switching valve 51 is provided. The pilot pressure may be controlled.

In the above-described embodiment, the master controller 81 controls the proportional control valve 52 and the slave controllers 82 and 83 control the direction switching valve 53, but this may be reversed. That is, the master controller 81 may control the direction switching valve 53 and the slave controllers 82 and 83 may control the proportional control valve 52.

In the above embodiment, the driving of the cylinders 34 to 36 is controlled by a plurality of hydraulic circuits, but the driving of each hydraulic driving device may be controlled by one hydraulic circuit. However, as described above, there is an advantage that the operation of the work machine can be continued even if an abnormality occurs in one system, by controlling with a plurality of hydraulic circuits.

In the embodiment, the output of the first operation signal output device 71 is input to the master controller 81 without branching, but the output of the first operation signal output device 71 is also branched in the same manner as the second operation signal output device 72. The first operation signal may be input to both the master controller 81 and the slave controller 82.

In the embodiment, the two operation signals of the first operation signal and the second operation signal are input to the master controller 81. However, only the first operation signal is input, and the control signal generation unit 813 uses the first operation signal as the first operation signal. A control signal may be generated based on this.
Also, when the number of terminals required for input increases and the number of input terminals included in the master controller increases, a plurality of master controllers can be provided. At this time, input from the operation tool is input to a plurality of master controllers, and each master controller controls a proportional control valve to be controlled.

The present invention is applicable not only to the hydraulic excavator (loading excavator) 1 shown in FIG. 1 but also to the backhoe excavator 1A shown in FIG. The backhoe excavator 1A includes a vehicle body 2 and a work implement 3A. The vehicle main body 2 has the same configuration as the loading excavator 1.
The work machine 3A includes a boom 31A for backhoe excavators, an arm 32A, and a bucket 33A, and a boom cylinder 34A, an arm cylinder 35A, and a bucket cylinder 36A that drive these. In the backhoe excavator 1A, the bucket 33A does not open and close, and therefore a crumb cylinder is not provided.
Furthermore, the present invention can be applied not only to a hydraulic excavator but also to various work machines having a hydraulic drive device driven by a hydraulic pump.

DESCRIPTION OF SYMBOLS 1 ... Hydraulic excavator, 2 ... Vehicle main body, 3 ... Working machine 5, 5A, 5B, 5C, 5D ... Hydraulic pump, 21 ... Traveling body, 22 ... Revolving body, 26 ... Revolving motor, 27 ... Elevating ladder, 28 ... Service arm 34 ... Boom cylinder, 35 ... Arm cylinder, 36 ... Bucket cylinder, 37 ... Clam cylinder, 40 ... Battery, 41 ... First relay, 42 ... Second relay, 43 ... Third relay, 44 ... ACC power source, 45 ... Emergency stop switch, 46 ... Work machine stop switch, 50 ... Hydraulic control valve, 51 ... Pilot-type direction switching valve, 52 ... Proportional control valve, 53 ... Direction switching valve, 60 ... Operating tool, 71 ... First operation signal Output device 72 ... second operation signal output device 80 ... pump controller 81 ... master controller as first control device 82, 83 ... slave controller as second control device Troller, 100 ... Electric motor, 101 ... First control relay, 102 ... Second control relay, 103 ... Third control relay, 104 ... Electric motor input power, 213L ... Left travel motor, 213R ... Right travel motor, 271 ... Ladder hydraulic cylinder, 281 ... service arm hydraulic cylinder, 401 ... power supply line.

Claims (7)

1. An emergency stop system for a work machine equipped with a work machine,
   An emergency stop switch,
   A work machine control device capable of controlling a stop operation of the work machine;
   A power source for supplying power to the work machine control device;
   A power supply line connecting the power source and the work implement control device;
   A first relay and a second relay provided in the power supply line to control power supply to the work implement control device;
   A second relay control device that detects an open / closed state of the emergency stop switch and controls the second relay;
   The first relay is controlled by the emergency stop switch, and in an emergency state where the emergency stop switch is input, the power supply line is disconnected.
   When the second relay control device detects an emergency state in which the emergency stop switch is input, the second relay control device controls the second relay to disconnect the power supply line,
   When the power supply line is cut by the first relay or the second relay and the power supply from the power source to the work implement control device is stopped, the work implement is stopped. Emergency stop system.
2. The emergency stop system for a work machine according to claim 1,
   The emergency stop system for a work machine, wherein the second relay disconnects the power supply line when a control signal is not input from the second relay control device.
3. In the emergency stop system of the working machine according to claim 1 or 2,
   The work machine control device includes:
   A first control device that controls driving of the work machine and a device other than the work machine;
   A second control device for controlling the drive of the working machine,
   The power supply line is provided with a third relay that controls only power supply to the second control device,
   When only the third relay is disconnected, only the second control device is stopped, and the work machine controlled by the second control device is stopped. An emergency stop system for a work machine.
4. The work machine emergency stop system according to claim 3,
   A work machine stop switch for controlling the third relay is provided;
   The third relay is controlled by the work implement stop switch, and when the work implement stop switch is input, the power supply line is cut off and the power supply to the second control device is cut off. Emergency stop system for working machines.
5. In the emergency stop system of the working machine according to claim 3 or claim 4,
   The work machine is a hydraulic excavator provided with a traveling body and an upper swinging body that is turnable on the traveling body,
   The upper turning body includes a ladder or a service arm. An emergency stop system for a work machine.
6. An emergency stop system for a work machine according to any one of claims 1 to 5,
   A drive mechanism that drives the work machine,
   The drive mechanism includes a hydraulic pump, a hydraulic drive device driven by hydraulic oil supplied from the hydraulic pump, and a hydraulic control valve that controls supply of hydraulic oil from the hydraulic pump to the hydraulic drive device. ,
   The work implement control device includes a valve controller that outputs a control signal for controlling the hydraulic control valve,
   When the first relay or the second relay is disconnected and the work implement control device stops and the control signal is not input from the work implement control device, the hydraulic control valve A work machine characterized by being in a stopped state in which supply is stopped.
7. A working machine,
   An emergency stop switch,
   A work machine control device capable of controlling a stop operation of the work machine;
   A power source for supplying power to the work machine control device;
   A power supply line connecting the power source and the work implement control device;
   A first relay and a second relay provided in the power supply line to control power supply to the work implement control device;
   An emergency stop method for a work machine, comprising: a second relay control device that detects an open / close state of the emergency stop switch and controls the second relay;
   In an emergency state where the emergency stop switch is input, the first relay disconnects the power supply line,
   The second relay control device that has detected an emergency state in which the emergency stop switch is input controls the second relay to disconnect the power supply line,
   When the power supply line is cut by the first relay or the second relay and the power supply from the power source to the work implement control device is stopped, the work implement is stopped. Emergency stop method.
   

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