JP4163137B2 - Hybrid excavator operating device - Google Patents

Description

  The present invention relates to an operating device for a hybrid excavator, and more particularly to an operating device for a hybrid excavator including a hydraulic actuator driven by hydraulic pressure and an electric actuator driven by electric power.

In recent years, various construction machines having improved work environments such as exhaust gas and noise have been proposed. One example is a hybrid construction machine that uses both an engine and an electric motor. This hybrid construction machine is provided with an electric motor driven by battery power in addition to an actuator hydraulic pump driven by engine power. When the actuator drive mode is switched, the drive of the hydraulic pump can be changed to “battery drive”, “engine drive”, or “engine drive and battery-assisted drive”. Thus, the engine load is reduced to improve exhaust gas, noise, and the like (see, for example, Patent Document 1).
Japanese Patent Laid-Open No. 2001-207482.

  The invention described in Patent Document 1 employs a method in which all the various actuators are driven by a hydraulic pump. However, from the viewpoint of work environment and functions, there are actuators that are more convenient to be driven by hydraulic pressure and actuators that are more convenient to be driven by electric power. Therefore, in the future, hybrid type excavators in which actuators driven by hydraulic pressure (hereinafter referred to as “hydraulic actuators”) and actuators driven by electric power (hereinafter referred to as “electric actuators”) are mixed. It is expected to increase.

  Thus, in a hybrid excavator in which a hydraulic actuator and an electric actuator are mixedly installed, two types of operating means, that is, an operating means for controlling the hydraulic actuator and an operating means for controlling the electric actuator are required. However, there is a problem that parts management becomes complicated and costs increase. In addition, hydraulic actuators generally use a hydraulic pilot operating valve that is operated by tilting an operating lever that is set to a neutral position. However, the electric actuator is not operated by an operating lever, for example, by a switch operation. Then, the problem that it is difficult for an unfamiliar operator to operate is expected.

  Therefore, in a hybrid excavator in which a hydraulic actuator and an electric actuator are mixed, an operation device that can share components and can operate the electric actuator by the same operation as the operation of the hydraulic actuator. The technical problem which should be solved arises in order to obtain, and this invention aims at solving this problem.

  The present invention has been proposed to achieve the above object, and the invention according to claim 1 includes a hydraulic actuator driven by a discharge hydraulic oil of a hydraulic pump, and an electric actuator driven by battery power. A pilot pump that generates a pilot hydraulic pressure for remote operation, and the electric pump is remotely operated by the pilot hydraulic pressure in a hybrid excavator in which the hydraulic pump and the pilot pump are driven by engine power A hydraulic pilot operating valve; a pressure sensor that converts the secondary pressure of the hydraulic pilot operating valve into an electric signal and outputs the electric signal; and a control unit that controls the electric actuator according to a signal from the pressure sensor. An operating device for a hybrid excavator is provided.

  According to this configuration, the same hydraulic pilot operation valve as the hydraulic pilot operation valve that operates the hydraulic actuator is used as the means for operating the electric actuator, and the same pilot pump as the hydraulic pilot operation valve that operates the hydraulic actuator The pilot oil discharged from the engine can be used to operate the hydraulic pilot operation valve for the electric actuator. Accordingly, the structure of the hydraulic pilot operation valve for operating the electric actuator can be made the same as that of the hydraulic pilot operation valve for operating the hydraulic actuator so that the operations can be shared. When the electric actuator is operated, when the hydraulic pilot operation valve for the electric actuator is operated, a pilot secondary pressure is generated from the hydraulic pilot operation valve, and this secondary pressure is detected by the pressure sensor. It is converted into an electric signal, and the electric signal is input to the control means as a signal for operating the electric actuator. The control means controls the electric actuator based on this signal.

  The invention according to claim 2 is characterized in that the hydraulic pilot operation valve is provided with an operation lever that is normally set at a neutral position and can be tilted to the left and right, and a tilt direction of the operation lever. A hybrid excavator having a port and a switching valve configured to output the secondary pressure from a port corresponding to the tilting direction of the operation lever, and the pressure sensor is provided for each port. An operating device is provided.

  According to this configuration, when the operation lever is tilted from the neutral position, the secondary pressure is output from the port corresponding to the tilt direction, and the secondary pressure is detected by the pressure sensor corresponding to the port, It is converted into an electrical signal and output to the control means. Therefore, the control means can identify the tilting direction of the operation lever from the electric signal of the pressure means.

  According to the first aspect of the present invention, a hydraulic pilot operating valve having the same structure as the hydraulic pilot operating valve used for operating the hydraulic actuator is used as means for operating the electric actuator. Since it can be shared, parts management becomes easy and it can contribute to cost reduction. Further, by using the hydraulic pilot operation valve having the same structure, the operation of the electric actuator can be performed with the same feeling as the operation of the hydraulic actuator, which can contribute to the improvement of operability. Furthermore, it is possible to take a form in which a hydraulic actuator and an electric actuator are mixed, and it is possible to provide an excavator according to the work environment and work contents.

  According to the second aspect of the present invention, a signal is obtained from the pressure sensor corresponding to the tilt direction in accordance with the direction in which the operation lever is tilted from the neutral position. In addition, the operated direction of the operation lever can be easily obtained from the signal of the pressure sensor.

  In a hybrid excavator with a mixture of hydraulic and electric actuators, the parts can be shared, and the operating device can be operated by the same operation as the hydraulic actuator. A hydraulic actuator driven by discharge hydraulic fluid of the hydraulic pump, an electric actuator driven by battery power, and a pilot pump for generating a pilot hydraulic pressure for remote operation, the hydraulic pump and the pilot pump A hydraulic pilot operating valve that remotely controls the electric actuator with the pilot hydraulic pressure, and converts the secondary pressure of the hydraulic pilot operating valve into an electric signal. A pressure sensor to output, and the electric power according to a signal from the pressure sensor. Control unit for controlling the system actuators to provide an operating device of a hybrid shovel which includes a city.

  Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings. FIG. 1 shows a side view of a hybrid excavator to which the present invention is applied. In FIG. 1, the hybrid excavator 10 has an upper swing body 13 mounted on a lower traveling body 11 via a swing mechanism 12 so as to be rotatable. The upper swing body 13 is provided with a cab 14 and a building 18, and a boom 15 is attached to the front center portion so as to be able to be raised and lowered. An arm 16 is attached to the tip of the boom 15 so as to be rotatable up and down, and a bucket 17 is attached to the tip of the arm 16.

  FIG. 2 is a circuit diagram showing the hydraulic and electric circuit configuration in the hybrid excavator shown in FIG. In FIG. 2, the hydraulic circuit includes a hydraulic actuator system unit 21 and an electric actuator system unit 22 that are power-connected to the engine 20.

  The hydraulic actuator system unit 21 is driven by a hydraulic pump 23 and a pilot pump 24 that are power-coupled to the engine 20 via a power transmission means and a clutch, and a discharge hydraulic oil sent from the hydraulic pump 23 through an oil pipe 32. The hydraulic motor 25 as a hydraulic actuator to be operated, the direction switching valve 26 interposed between the hydraulic motor 25 and the hydraulic pump 23, and the hydraulic pressure of pilot oil discharged from the pilot pump 24 (hereinafter referred to as “ The pilot pressure control valve 27 is provided with a hydraulic pressure pilot operation valve 27 for remotely operating the direction switch valve 26. Note that a plurality of hydraulic motors 25, direction switching valves 26, and hydraulic pilot operation valves 27 are provided in accordance with the number of actuators driven by the hydraulic oil of the hydraulic pump 23, but here, for the sake of simplicity. The case where only one is provided is shown.

  The hydraulic pilot operation valve 27 is installed on an operation table (not shown) provided at a position where an operator sitting in the driver's seat of the cab 14 can operate by hand, and an operation projecting upward from the operation table. A lever 28 is provided. The operation lever 28 has a rod shape, and a bearing portion 29 is provided at the base end portion. By inserting a support shaft 29a into the bearing portion 29, the operation lever 28 is rotatably supported with the support shaft 29a as a fulcrum. It is in the state that was done.

  Further, the bearing portion 29 is provided with a bar 30 extending in the left-right direction, and a pair of switching valves 31a and 31b are provided below the both side portions of the bar 30 via coil springs. In general, the operation lever 28 is set to a neutral position upright by the urging force of each coil spring. In the state where the operation lever 28 is in the neutral position, the direction switching valve 26 is set to the hydraulic oil cutoff position as shown in FIG. 2, whereby the hydraulic motor 25 is stopped.

  Then, when the operation lever 28 is tilted to the right in FIG. 2, for example, with the support shaft 29a as a fulcrum, the switching valve 31a is opened, and the first pilot line 33a, the right switching valve 31a and the second pilot pipe are opened. The passage 33b communicates, and the pilot hydraulic pressure from the pilot pump 24 is applied to the right switching valve 31a and the second pilot pipeline 33b. As a result, the direction switching valve 26 moves to the right, and the discharge hydraulic oil from the hydraulic pump 23 flows from the left to the right of the hydraulic motor 25, and the hydraulic motor 25 rotates in the forward direction. For example, the crawler 19 rotates in the forward direction by the rotation of the hydraulic motor 25 and the hybrid excavator 10 moves forward. When the operating lever 28 is returned to the neutral position, the switching valve 31a is also returned to the closed state, and at the same time, the direction switching valve 26 is also returned to the hydraulic oil cutoff position, and the hybrid excavator 10 stops moving forward.

  On the other hand, in the state shown in FIG. 2, when the operation lever 28 is tilted leftward, the switching valve 31b opens, and the first pilot line 33a, the leftward switching valve 31b, and the third pilot line 33c communicate with each other. Thus, the pilot hydraulic pressure from the pilot pump 24 is supplied to the left switching valve 31b and the third pilot pipe line 33c. As a result, the direction switching valve 26 moves to the left and the discharge hydraulic oil from the hydraulic pump 23 flows in the hydraulic motor 25 from the right to the left, and the hydraulic motor 25 rotates in the reverse direction. The crawler 19 rotates in the reverse direction by the rotation of the hydraulic motor 25 and the hybrid excavator 10 moves backward. When the operation lever 28 is returned to the neutral position, the switching valve 31b is also returned to the closed state, and at the same time, the direction switching valve 26 is also returned to the hydraulic oil shut-off position, and the hybrid excavator 10 stops moving backward.

  The electric actuator system unit 22 includes a control unit 40, a generator 41 that is power-coupled to the engine 20 via a power transmission means such as a belt and a clutch, a battery 42, pressure sensors 43a and 43b, and a hydraulic pilot operation. The valve 44 and an electric motor 45 as an electric actuator are provided. Also in this electric actuator system section 22, a plurality of pressure sensors 43a, 43b, hydraulic pilot operation valves 44, and electric motors 45 are provided according to the number of actuators that are electrically driven. Then, in order to simplify the explanation, a case where only one is provided is shown.

  The control part 40 is comprised as a microcomputer which controls the whole electric actuator system | strain part 22, and controls the starting / stopping and rotation direction of the electric motor 45, for example according to the procedure programmed beforehand.

  The generator 41 converts the mechanical energy rotated by the engine 20 into electrical energy and stores it in the battery 42.

  The pressure sensors 43a and 43b detect the pilot secondary pressure generated in the first output port 46a or the second output port 46b after being controlled by the hydraulic pilot operation valve 44, and use the pilot secondary pressure as an electrical signal. It is a sensor that converts and sends it to the control unit 40.

  The hydraulic pilot operation valve 44 has the same structure as that of the hydraulic pilot operation valve 27, and is provided at a position where an operator sitting on the driver's seat of the cab 14 can manually operate, like the hydraulic pilot operation valve 27. It has been. Therefore, the same reference numerals are given to members corresponding to the hydraulic pilot operation valve 27, and redundant description is omitted.

  The pilot pressure of pilot oil from the pilot pump 24 that is the same as that of the hydraulic pilot operation valve 27 is applied to the hydraulic pilot operation valve 44. The pilot oil pressure of the pilot oil generates a pilot secondary pressure in the first output port 46a when the switching valve 31a is opened and the first pilot pipe line 33a and the first output port 46a communicate with each other. On the contrary, when the switching valve 31b is opened and the first pilot line 33a and the second output port 46b are communicated with each other, a secondary pressure is generated in the second output port 46b.

  Next, the operation of the electric actuator system unit 22 using the hydraulic pilot operation valve 44 configured as described above will be described. The operation lever 28 of the hydraulic pilot operation valve 44 is normally set at a neutral position upright by the urging force of each coil spring. In the state where the operation lever 28 is in the neutral position, the switching valves 31a and 31b of the hydraulic pilot operation valve 44 are arranged such that the pilot oil pilot hydraulic pressure is applied to the first output port 46a and the second output port 46b as shown in FIG. Is set at a non-applied blocking position, and no pilot secondary pressure is generated in any of the first output port 46a and the second output port 46b. This information is input to the control unit 40 via the pressure sensors 43a and 43b, and the control unit 40 controls the hydraulic motor 45 to a stopped state.

  When the operation lever 28 of the hydraulic pilot operation valve 44 is tilted to the right in FIG. 2, for example, with the support shaft 29a as a fulcrum, the switching valve 31a is opened, and the first pilot line 33a and the right switching valve 31a are opened. And the first output port 46a communicate with each other, and a pilot secondary pressure is generated in the first output port 46a. The pilot secondary pressure is detected by the pressure sensor 43a, further converted into an electric signal, and sent to the control unit 40. As a result, the electric motor 45 is supplied with current from the battery 42 in the forward direction under the control of the control unit 40, and the electric motor 45 rotates in the forward direction. For example, the arm 16 is rotated upward by the rotation of the electric motor 45. When the operation lever 28 is returned to the neutral position, the switching valve 31a is also returned to the closed state, and at the same time, the secondary pressure detected by the pressure sensor 43a is reduced, and the control unit 40 stops the electric motor 45, As a result, the rotation of the arm 16 is also stopped.

  On the contrary, in the state shown in FIG. 2, when the operation lever 28 is tilted leftward, the switching valve 21b is opened, and the first pilot line 33a, the leftward switching valve 31b, and the second output port 46b communicate with each other. A pilot secondary pressure is generated in the second output port 46b. The pilot secondary pressure is detected by the pressure sensor 43b, further converted into an electric signal, and sent to the control unit 40. As a result, the electric motor 45 is supplied with the current from the battery 42 in the reverse direction under the control of the control unit 40, and the electric motor 45 rotates in the reverse direction. For example, the arm 16 is rotated downward by the rotation of the electric motor 45. When the operation lever 28 is returned to the neutral position, the switching valve 31b is also returned to the closed state, and at the same time, the secondary pressure detected by the pressure sensor 43b is lowered, and the control unit 40 stops the electric motor 45, As a result, the rotation of the arm 16 is also stopped.

  Therefore, in the hybrid excavator according to the present embodiment configured as described above, as a means for operating the electric actuator (electric motor 45), the hydraulic pilot operation valve used in the operation of the hydraulic actuator (hydraulic motor 25). The hydraulic pilot operation valve 44 having the same structure as that of the hydraulic pilot operation valve 27 can be used in common, so that the parts management is simplified and the cost can be reduced. Further, by using the hydraulic pilot operation valves 27 and 44 having the same structure, the operation of the electric actuator can be performed with the same feeling as the operation of the hydraulic actuator, which can contribute to the improvement of operability. Furthermore, it is possible to take a form in which hydraulic actuators and electric actuators coexist, and it is possible to provide an excavator corresponding to the work environment and work contents.

  It should be noted that the present invention can be variously modified without departing from the spirit of the present invention, and the present invention naturally extends to the modified one.

The side view of the hybrid shovel to which this invention is applied. The circuit diagram of the hydraulic-pressure and electric circuit structure in a hybrid shovel same as the above.

Explanation of symbols

20 Engine 21 Hydraulic Actuator System 22 Electric Actuator System 23 Hydraulic Pump 24 Pilot Pump 25 Hydraulic Motor (Hydraulic Actuator)
26 Directional switching valve 27 Hydraulic pilot operated valve
28 Operation lever 31a, 31b Switching valve 33a 1st pilot pipe line 33b 2nd pilot pipe line 33c 3rd pilot pipe line 40 Control part 42 Battery 43a, 43b Pressure sensor 44 Hydraulic pilot operation valve
45 Electric motor (electric actuator)
46a First output port 46b Second output port

Claims (2)

A hydraulic actuator driven by discharge hydraulic fluid of a hydraulic pump, an electric actuator driven by battery power, and a pilot pump that generates a pilot hydraulic pressure for remote operation, the hydraulic pump and the pilot pump being an engine In the hybrid excavator driven by the power of
A hydraulic pilot operating valve for remotely operating the electric actuator with the pilot hydraulic pressure;
A pressure sensor that converts the secondary pressure of the hydraulic pilot operated valve into an electrical signal and outputs the electrical signal;
A control unit for controlling the electric actuator according to a signal from the pressure sensor;
An operation device for a hybrid excavator characterized by comprising:   The hydraulic pilot operation valve has an operation lever that can be tilted to the left and right, which is normally set to a neutral position, and a plurality of ports provided corresponding to the tilt directions of the operation lever, and The hybrid excavator operating device according to claim 1, further comprising: a switching valve configured to output the secondary pressure from a port corresponding to a tilting direction of the operating lever, wherein the pressure sensor is provided for each port.

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