JP2001226077A - Construction machinery with electric actuator for working machine and swing drive device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide construction machinery having an actuator for working machine and a swing drive device with increased controllability and responsiveness. SOLUTION: Inverter-controlled motors 8 and 10 are used as drive sources for a working machine actuator and a swing drive device, and the output from inverters 4 and 5 is controlled by a controller 14 according to output signals from a control lever 13. The control mode of the controller 14 is changeable by a mode switch 12.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a power shovel,
The present invention relates to a construction machine including an electric working machine actuator such as a crawler crane and a truck crane and a turning drive device.

[0002]

2. Description of the Related Art A conventional power shovel has a configuration shown in FIGS.

[0005] First, as shown in FIG. 5, a pump 41 of a hydraulic circuit is driven by an engine 40, and the hydraulic pressure generated by the pump 41 is transmitted through a control valve 42 to a working machine driving hydraulic cylinder 44 and a hydraulic turning motor 43. And the hydraulic traveling motor 46 was driven. In addition, 45 is a center joint, 48 is a traveling section, 49 is a turning section, and 50 is a working section.

FIG. 6 is a block diagram showing a hydraulic system. The hydraulic circuit that constitutes this system includes a control valve 42 directly from a hydraulic pump 41 coupled to the engine 40.
And a circuit for supplying and discharging the hydraulic cylinder 44 from the control valve 42, a circuit for supplying and discharging the hydraulic turning motor 43, and a circuit for supplying and discharging the hydraulic traveling motor 46. In this circuit, various hydraulic motors 4 constituting a load are supplied to a hydraulic pump 41 as a pressure source.
Simultaneous control of a plurality of objects such as actuators 3, 46 and hydraulic cylinder 44 was performed. Further, 47 is a hydraulic oil tank, 48 is a traveling section, 49 is a turning section, 50 is a working section (boom, arm, bucket), and the hydraulic system has a high-pressure circuit portion due to the need to generate a driving force. Was.

[0005]

However, the above-mentioned hydraulic circuit has problems of oil leakage from the connecting portion, poor responsiveness based on oil expansion and contraction characteristics, and difficulty in control due to control and switching shocks. was there. Further, in the above-described hydraulic drive system, when the driver operates the operation lever,
Hydraulic horsepower is distributed by the load of the actuator and the opening characteristics of the hydraulic valve, which makes it easier for pressure oil to flow to the actuator with a light load.As a result, the operation of the entire machine is biased, and the operator must adjust the operation lever each time. Therefore, there are problems such as poor operability due to insufficient pump flow pressure during simultaneous control of a plurality of loads.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a construction machine having an electric working machine actuator and a turning drive device with improved responsiveness and operability.

[0007]

According to the present invention, in order to achieve the above object, [1] In a construction machine having an electric working machine actuator and a swing drive device, a drive source and a swing of the working machine actuator are provided. An electric motor that is a driving source of the driving device; an inverter that controls the electric motor; a controller that controls the inverter; and an operation lever that inputs a setting operation signal to the controller. To perform predetermined arithmetic processing,
The inverter is controlled based on the calculation result.

[2] In the construction machine provided with the electric working machine actuator and the turning drive device according to [1], a controller having a plurality of control modes and an arbitrary mode from among the plurality of control modes are provided. It has a mode switch that can be set.

[3] In a construction machine comprising the electric working machine actuator and the turning drive device according to [1] or [2], data for controlling the controller by detecting the rotation speed of the electric motor is provided. It is characterized by having an encoder to perform.

Therefore, according to the construction machine provided with the electric working machine actuator and the turning drive device according to the above [1], the controller performs a predetermined calculation in accordance with the operation setting of the operation lever, and the inverter performs the calculation. The motor can be controlled with high control accuracy and individually in response to the results.

According to the construction machine having the electric working machine actuator and the turning drive device described in the above [2], both inverters can be operated in parallel by the controller at an arbitrary setting by the controller. The combined operation with the driving of the turning drive device can be easily performed.

According to the construction machine having the electric working machine actuator and the turning drive device described in the above item [3], the rotational speed of the electric motor is detected by the encoder, so that the detected data is code data which can be easily processed by the controller. It can be.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings showing the embodiments.

(First Embodiment) FIG. 1 shows a first embodiment of the present invention.
FIG. 2 is a schematic diagram of a construction machine (shovel) showing an embodiment, FIG. 2 is a block diagram of a power control system for a motor of the construction machine, and FIG. 3 is a block diagram of a control system of the whole machine.

In FIG. 2, reference numeral 1 denotes a power supply, which can be used with either AC or DC. A voltage / current detector 2 detects a power supply voltage and a power supply current. Reference numeral 3 denotes a converter, which has a function of converting a power supply output to DC.
Reference numerals 4 and 5 denote inverters (converters), which convert the output of the converter 3 into a high-frequency AC output. Reference numerals 6 and 7 denote voltage / current detectors for detecting output voltages and output currents of the inverters 4 and 5, respectively.

Reference numerals 8 and 10 denote AC (AC) motors, which are induction motors having characteristics suitable for being driven by an inverter. Reference numerals 9 and 11 denote encoders, and AC motors 8 and 10
And outputs code data by detecting the number of rotations. Reference numeral 12 denotes a mode switch, which makes it possible to select the ratio of power input to the working machine and the turning motor / motor generator to a plurality of work patterns by a mode selection function, and to set various modes by program control of the controller 14. Possible, for example, a standard mode in which electric power is evenly distributed to each electric motor during combined operation, a work equipment priority mode in which the power of the work machine is prioritized and a large amount of power is distributed, a turning priority mode in which the turning speed is prioritized and a large amount of power is distributed, and a work implement part In addition, it is possible to set a mode such as a speed compensation mode for limiting a constant speed, a maximum speed limit, and the like to the turning section, and to operate the AC motors 8 and 10 independently, in a parallel operation, in a constant speed mode for facilitating work, and in a load mode. This is input means for selecting an operation mode such as a shift mode corresponding to the operation mode.

The operator can select the mode according to the working conditions and the skill level, and can secure the most convenient operating conditions.
Work efficiency can be improved.

An operation lever 13 outputs various setting operation signals according to the operation. Separate operation levers for the working machine and for the turning may be provided, or may be shared. Further, it may be linked with the mode switch 12.

Reference numeral 14 denotes a controller (control device).
Equipped with a programmable CPU, voltage / current detector 2,
The converters 3 and the inverters 4 and 5 are controlled in accordance with the input from the mode switch 12 and the operation lever 13 based on the detection data from the encoders 6 and 7 and the encoders 9 and 11 so that the AC motors 8 and 10 are individually or in parallel. To control.

FIG. 3 is a block diagram of the entire control system (dotted lines indicate portions of the second embodiment).

In FIG. 1, the controller 14 basically includes an input / output port, a CPU, and a memory. The input port includes an operation lever 13, encoders 9, 11, voltage / current detectors 2, 6, 7, an expansion / contraction detection sensor 15 for detecting the expansion / contraction state of an actuator for a working machine such as a boom, an arm, and a bucket, and a load detection. The sensor 16, the turning angle detection sensor 17, and the mode switch 12 are connected.

The output port is connected to the converter 3, the inverters 4 and 5, and the monitor device 18.

The operation of the construction machine of the first embodiment configured as described above will be described below.

First, by the mode switch 12, the AC motor 8 for the working machine and the AC
The driving mode of the electric motor 10 is set and registered in the memory. Next, a setting operation signal is output by operating the operation lever 13. The controller 14 controls the operation setting signal,
In addition to taking in the rotation speed data from the encoders 9 and 11, the voltage values and the current values from the voltage / current detectors 2, 6 and 7, and searching a table or the like stored in the memory, a predetermined program is executed. The converter 3 and the inverters 4 and 5 are controlled such as frequency control, phase control, and duty ratio control to cause the AC motors 8 and 10 to perform predetermined operations. Since the outputs of the inverters 4 and 5 are harmonic outputs, the control output can be made fine, and the control input can be finely set, so that the operability is good. (Operation of AC Motor for Work Machine) Controller 14
Changes the output of the inverter 4 according to the setting operation signal of the operation lever 13 and drives the work machine AC motor 8 to perform the extension / contraction drive of the boom, the arm, and the bucket. At that time, based on the detection data of the expansion / contraction detection sensor 15, for example, the controller 14 controls the speed to linearly increase at the beginning of the expansion / contraction operation, maintain a constant speed in the middle, and decrease the speed linearly at the end. This allows for soft start,
Soft landing can be achieved. Further, the controller 14 can control the speed of the work machine AC motor 8 according to the detection data of the load detection sensor 16 to increase the speed for a light load and to decrease the speed for a heavy load. (Operation Mode of Turning AC Motor) The controller 14
The output of the inverter 5 is changed according to a setting operation signal of the operation lever 13 to drive the turning AC motor 10 to turn the work machine. At this time, the output of the turning angle detection sensor 17 per unit time is calculated, and the load detection sensor 16
Are obtained by calculating the inertia force of the working unit from these data, and the turning AC motor 10 is controlled such that the inertia force falls within a predetermined range. The operation lever 13,
When the setting operation signal of the mode switch 12 is set to the constant speed control, the controller 14 controls the inverter 5 while reading the detection data of the encoder 11 to control the turning AC motor 10 at a constant speed. (Operation Mode of Combined Operation) In the combined work of the working machine AC motor 8 and the turning AC motor 10, the controller 14 controls the turning AC motor 10 to turn the turning AC motor 10 in order to facilitate the work. 17 and encoder 11
While operating at a constant speed based on the detection data of
The inverters 4 and 5 can be controlled so that the work machine AC motor 8 is driven at a variable speed in response to the setting operation signal of 3. In addition, the controller 14 controls the inverters 4 and 5 so that the working machine AC motor 8 and the turning AC motor 10 are operated in an arbitrary relationship by the setting operation signal of the operation lever 13 and the mode switch 12. be able to.

FIG. 4 is a schematic view of a construction machine (crane) showing a second embodiment of the present invention. The winding detection sensor in this embodiment is indicated by a dotted line in FIG.

As shown in this figure, this construction machine (crawler crane) includes an AC motor 21 for an electric winch (for working machine) for lifting and lifting, an AC motor 22 for an electric winch (for working machine) for raising and lowering a boom, and a swing. AC motor 23 is provided, and the converter is controlled based on the output of the winding detection sensor 19 in the same manner as in the first embodiment. 24 is a running motor, 25 is a boom, and 26 is a hook. (Other Embodiments) The power source includes a generator coupled to the engine, a fuel cell, a commercial power source, and the like, and these battery backups are selectively performed. If a second stage converter is connected after the inverter, a DC (direct current) motor, a pulse motor or the like can be used as the motor.

The operation lever 13 and the mode switch 12 can be replaced by wireless or wired remote operation means as alternative means.

It should be noted that the present invention is not limited to the above-described embodiment, and various modifications are possible based on the spirit of the present invention, and these are not excluded from the scope of the present invention.

[0029]

As described above, according to the present invention, an AC having good responsiveness and operability is provided.
An AC motor for driving a working machine actuator via a power control means including an individually controllable converter and an inverter using an electric motor for each drive source, and a turning A
Since the C motor is controlled, simultaneous control of a plurality of loads, which is not easy with the conventional hydraulic drive, is facilitated. Further, since the simultaneous control of a plurality of loads has become easier, the operability at the time of the combined operation has been remarkably improved. A wide range of work modes can be selected with the mode switch, which improves operability in conjunction with the setting operation of the operation lever. Since the output of the inverter is a harmonic output,
The control output can be made fine, and the control input can also be set finely.

[Brief description of the drawings]

FIG. 1 is a schematic diagram of a construction machine according to a first embodiment of the present invention.

FIG. 2 is a block diagram of a power control system according to the first embodiment of the present invention.

FIG. 3 is a block diagram of a control system of the entire machine according to the first embodiment of the present invention (dotted lines indicate portions of the second embodiment).

FIG. 4 is a schematic view of a construction machine (crane) showing a second embodiment of the present invention.

FIG. 5 is a hydraulic block diagram including an arrangement in a conventional hydraulic shovel.

FIG. 6 is a hydraulic block diagram of a conventional hydraulic excavator.

[Explanation of symbols]

Reference Signs List 1 power supply 2, 6, 7 voltage / current detector 3 converter 4, 5 inverter 8 AC motor for work machine 9, 11 encoder 10 AC motor for turning 12 mode switch 13 operating lever 14 controller (control device) 15 expansion / contraction detection sensor 16 Load detection sensor 17 Rotation angle detection sensor 18 Monitor device 21 Electric winch for lifting load (for working machine) AC
Electric motor 22 For electric winch for boom hoist (for work machine) AC
Electric motor 23 AC motor for turning 24 Electric motor for traveling 25 Boom 26 Hook

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Takashi Kubo 731-1 Naganumaharamachi, Inage-ku, Chiba-shi, Chiba F-term (reference) 2D003 AA01 AA06 AB02 AB03 AB04 AC06 BA01 BA02 CA10 DA04 DB01 DB04 DB05 3F205 AA07 EA08 EA10

Claims (3)

[Claims] 1. An electric motor, which is a drive source of a working machine actuator and a drive source of a turning drive device, an inverter that controls the electric motor, a controller that controls the inverter, and an operation of inputting a setting operation signal to the controller A construction comprising an electric working machine actuator and a swing drive device, wherein the controller performs a predetermined calculation process based on the setting operation signal and controls the inverter based on the calculation result. machine. 2. A construction machine comprising an electric working machine actuator and a turning drive device according to claim 1, wherein a controller having a plurality of control modes and an arbitrary mode can be set from among the plurality of control modes. A construction machine comprising an electric working machine actuator having a mode switch and a turning drive device. 3. A construction machine comprising an electric working machine actuator and a turning drive device according to claim 1 or 2, further comprising an encoder that detects a rotation speed of the electric motor and uses the detected rotation speed as data for control of a controller. A construction machine comprising an electric working machine actuator and a turning drive device.