JPH0617302U - Drive controller for electric / hydraulic drive vehicle - Google Patents

Abstract

(57) [Abstract] [Purpose] To suppress the repetition of start and stop of the electric motor in a short time at the time of inching operation, etc., and to stop the drive of the electric motor as much as possible at neutral. [Structure] When the traveling operation control lever 7a is operated, the power supply control circuit 20 controls on / off of power supply from the battery 11 to the electric motor 12 according to the operation.
When the traveling operation lever 7a is in the position for traveling, electric power is supplied to the electric motor 12 so that the electric motor 1 is driven.
2 is driven, and the electric power supply to the electric motor 12 is cut off when the traveling operation lever 7a is in the neutral position. However, a delay circuit 21 is provided in the power supply control circuit 20, and when the traveling operation lever 7a is returned to the neutral position and the power supply from the battery 11 to the electric motor 12 is cut off, a predetermined period is set. After a time delay, the power supply is cut off.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention drives a hydraulic pump by an electric motor driven by an on-vehicle battery, and drives a traveling crawler, wheels, etc. by a hydraulic motor driven by receiving a hydraulic pressure supply from the hydraulic pump to drive the vehicle. It relates to electric / hydraulic drive vehicles that have become popular.

[0002]

[Prior art]

 Such electric / hydraulic drive vehicles are used for relatively small aerial work vehicles, etc., and traveling control is performed by an operator on the vehicle operating a traveling control lever, etc. . When the travel control lever is operated, the operation of the hydraulic control valve that controls the amount of oil supplied from the hydraulic pump to the hydraulic motor is controlled in accordance with the operation, and this controls the drive of the hydraulic motor, and Travel control is performed.

When the travel control lever is in the neutral position, the hydraulic control valve may be used to drive the vehicle with the amount of oil supplied to the hydraulic motor reduced to zero. At this time, however, it is not necessary to drive the electric motor either. It is desirable to stop the power supply to the electric motor to reduce the battery power consumption as much as possible. For this reason, in the conventional electric / hydraulic drive vehicle, when the travel control lever is located in the neutral position, the hydraulic control valve is closed to stop the hydraulic pressure supply to the hydraulic motor and the electric power from the battery to the electric motor is stopped. The supply was supposed to be stopped.

[0004]

[Problems to be solved by the device]

 With this configuration, electric power is supplied from the battery and the electric motor is driven only when traveling, so that efficient traveling control can be performed and the battery life can be extended. However, in the case of running control in which the inching operation is frequently repeated, the electric motor is repeatedly started and stopped, and a large current flows from the battery to the electric motor each time the electric motor is started. There is a problem that the power supply becomes large and that it has an adverse effect on the contacts of the switch that controls the power supply.

The present invention has been made in view of such a problem. When an inching operation or the like is performed, the electric motor does not have to be repeatedly started and stopped in a short time, and the electric motor can be operated at a neutral position. It is an object of the present invention to provide a drive control device configured to stop driving of an electric motor as much as possible to suppress battery consumption.

[0006]

[Means for Solving the Problems]

 In order to achieve such an object, in the present invention, when the traveling operation means (traveling operation lever, switch, etc.) is operated by the operator, the power supply control circuit changes the operation from the battery to the electric motor in response to this operation. Controls the power supply on / off. For example, when the traveling operation means is in the position for traveling, electric power is supplied to the electric motor to drive the electric motor, and when the traveling operation means is in the neutral position, power supply to the electric motor is cut off. However, a delay circuit is provided in this power supply control circuit, and a predetermined time is required to cut off the power supply from the battery to the electric motor when the traveling operation means is returned to the neutral position. After a delay, the power supply is cut off.

[0007]

[Action]

 When the drive control device having such a configuration is used, when the operation of moving the traveling operation means to the traveling position is performed, the power supply control circuit responds to this operation by supplying power from the battery to the electric motor. Let As a result, the electric motor is driven to drive the hydraulic pump, and the hydraulic motor is driven by receiving the hydraulic pressure supply from the hydraulic pump, and the vehicle is driven to travel. On the other hand, when the travel operation means is returned to the neutral position, the delay circuit operates, and the power supply control circuit stops the power supply after a predetermined time delay from the time when the travel control signal is input. That is, when the traveling operation means is returned to the neutral position, the driving of the electric motor is not stopped at the same time, but the driving of the electric motor is stopped after a predetermined time delay. Therefore, when the traveling operation means is switched between the traveling position and the neutral position in a short time such as an inching operation, the electric motor is continuously driven. This prevents the electric motor from being started and stopped in a short time, improving the durability of the battery and the durability of the switch contacts.

[0008]

【Example】

 Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. As an example of an electric / hydraulic drive vehicle having a drive control device according to the present invention, a scissor type self-propelled aerial work vehicle is shown in FIG. This aerial work vehicle has crawlers 8 wound around a drive sprocket 8a, rolling wheels 8b and idler wheels 8c on both left and right sides of the vehicle body 1. The drive sprocket 8a is driven by the hydraulic motor 16, which drives the vehicle. In the vehicle body 1, a battery 11, an electric motor 12 that is driven to rotate by receiving electric power from the battery 11, and a hydraulic pump 15 that is driven by the electric motor 12 are mounted. Is hydraulically supplied from the hydraulic pump 15 and is rotationally driven.

A scissor link 2 is mounted on the vehicle body 1, and a workbench 4 is mounted on the scissor link 2. The scissor link 2 is adapted to be expanded and contracted upward and downward by the elevating cylinder 3, and according to the expansion and contraction of the elevating cylinder 3, the workbench 4 moves upward and downward as shown by a solid line and a two-dot chain line in the figure. It is moved up and down between positions. In this way, an operator (worker) gets on the work table 4 that is raised and lowered to perform work in high places. Therefore, a safety handrail 5 is provided, and an operation control device 6 having operation levers 7a and 7b for performing a vehicle traveling control operation and a workbench elevation control operation is provided on the front portion of the handrail 5. .

By operating the traveling operation lever 7a of the operation control device 6, the drive control of the hydraulic motor 16 is performed to control the traveling drive of the vehicle, and by operating the elevating operation lever 7b, the elevating cylinder 3 is moved. The extension / contraction control is performed to control the work table 4 up and down. In the following, traveling drive control associated with the operation of the traveling operation lever 7a will be described. Since the raising / lowering control of the workbench 4 by operating the raising / lowering operation lever 7b is well known in the art and is not directly related to the configuration of the present invention, its description is omitted.

The overall configuration of the traveling drive control device is shown in FIG. Electric power from the battery 11 is supplied to the electric motor 12 via the operation control device 6 and the power supply control circuit 20. The operation control device 6 has a travel changeover switch 6a which is operated according to the operation of the travel operation lever 7a, and a variable resistor 6b which constitutes a potentiometer. The travel operation lever 7a can be operated between a forward drive position, a neutral position and a reverse drive position. When the travel operation lever 7a is in the neutral position, the travel changeover switch 6a is turned off, and when it is in the forward drive or reverse drive position, it is turned on. Further, in the forward drive position and the reverse drive position, the control is performed such that the forward drive speed or the reverse drive speed is increased as the distance from the neutral position increases, and this forward drive or reverse drive operation amount is controlled by the variable resistance that constitutes the potentiometer. Detected by 6b.

The power supply control circuit 20 is connected to the travel changeover switch 6a. Therefore, when the traveling operation lever 7a is operated from the neutral position to the forward side and the traveling changeover switch 6a is turned on, the current from the battery 11 is directly transmitted from the line 31 via the delay circuit 21 to the contactor (electromagnetic switch). 22 to turn on the switch 22a of the contactor 22. As a result, a current flows from the battery 11 to the electric motor 12 via the line 33, and the electric motor 12 is rotationally driven. A hydraulic pump 15 is connected to the electric motor 12, the hydraulic pump 15 is driven by the electric motor 12, and the discharged oil is supplied to the hydraulic motor 16 via a travel control valve 28. A drive sprocket 8a is connected to the hydraulic motor 16, and when the hydraulic motor 16 is driven by being supplied with hydraulic pressure from the hydraulic pump 15, the drive sprocket 8a is rotationally driven to drive the vehicle.

On the other hand, an operation signal from the potentiometer 6b is output from the line 34 to the travel control valve 28 via the speed control circuit 25. Therefore, when the traveling operation lever 7a is operated from the neutral position to the forward side as described above, a signal corresponding to the operation direction and the operation amount of the traveling operation lever 7a is sent to the speed control circuit 25 to control the speed. The circuit 25 controls the travel control valve 28 in response to these signals. As a result, the supply direction and supply amount of the hydraulic oil supplied from the hydraulic pump 15 to the hydraulic motor 16 are controlled. That is, when the traveling operation lever 7a is operated to the forward side, the hydraulic oil supply direction is set so that the hydraulic motor 16 rotationally drives the driving sprocket 8a to the forward side, and the amount of oil at that time is set to the traveling operation. The larger the operation amount of the lever 7a, the larger it becomes. Thus, the vehicle can be moved forward by operating the traveling operation lever 7a from the neutral position to the forward side, and the traveling speed at that time can be adjusted according to the operation amount of the traveling operation lever 7a. The same applies when the traveling operation lever 7a is operated to the reverse side.

Next, when the traveling operation lever 7a thus operated forward is returned to the neutral position, the traveling changeover switch 6a is turned off. As a result, the power supply via the line 31 is cut off. However, when this switching from ON to OFF is performed, the delay circuit 21 operates to supply the power through the line 32 for a predetermined time and completely cut off the power supply after the predetermined time. Has become. Therefore, even if the traveling operation lever 7a is returned to the neutral position, the contactor 22 is energized for a predetermined time, the switch 22a thereof is held in the ON state, and the electric motor 12 is continuously driven. Then, after a predetermined time delay, the power supply is cut off, the switch 22a is turned off, and the power supply to the electric motor 12 is cut off.

As described above, the power supply to the electric motor 12 is not interrupted until a predetermined time elapses after returning from the forward movement position to the neutral position, so that, for example, the traveling operation lever 7a is inching in order to make the vehicle travel very slowly. When the operation, that is, the operation of frequently switching between the neutral position and the forward position is performed, the lever 7a is switched to the forward position again after the power supply is cut off after the lever 7a is returned to the neutral position. In other words, the electric motor 12 is continuously driven. This prevents the operation control such that the electric motor 12 is repeatedly started and stopped frequently when the traveling operation lever 7a is operated by inching.

In this embodiment, the scissors type self-propelled work vehicle having the crawler type drive device has been described as an example, but the present invention is also applicable to a vehicle having a wheel type drive device, and Of course, it can be used for other types of work vehicles.

[0017]

[Effect of device]

 As described above, according to the present invention, when the operation of moving the traveling operation means (lever or the like) to the traveling position is performed, the power supply control circuit responds to this operation by supplying power from the battery to the electric motor. Then, the electric motor is driven, the hydraulic pump is driven, and the hydraulic motor is driven by receiving the hydraulic pressure supply from the hydraulic pump, and the vehicle is driven to travel. On the other hand, when the traveling operation means is returned to the neutral position from this state, the delay circuit operates, and the power supply control circuit stops the power supply after a predetermined time delay from the time when the travel control signal is input. . That is, when the traveling operation means is returned to the neutral position, the driving of the electric motor is not stopped at the same time, but the driving of the electric motor is stopped after a predetermined time delay. Therefore, when the traveling operation means is switched between the traveling position and the neutral position in a short time, such as inching operation, the electric motor is continuously driven, and the electric motor is driven in a short time. It is possible to improve the durability of the battery as well as the durability of the switch contacts because it is not started and stopped.

[Brief description of drawings]

FIG. 1 is a perspective view of an aerial work vehicle having a drive control device according to the present invention.

FIG. 2 is a circuit diagram showing a configuration of this drive control device.

[Explanation of symbols]

 2 Scissor link 3 Lifting cylinder 4 Working table 8 Crawler 11 Battery 12 Electric motor 15 Hydraulic pump 16 Hydraulic motor

Claims (1)

[Scope of utility model registration request] 1. A battery mounted on a vehicle, and an electric motor driven by electric power supplied from the battery,
A drive control device for an electric / hydraulic drive vehicle, comprising: a hydraulic pump driven by the electric motor; and a hydraulic motor driven by the hydraulic pressure supplied from the hydraulic pump to drive the vehicle. A traveling operation means that is operated to control traveling of the vehicle, an electric power supply control circuit that controls electric power supply from the battery to the electric motor according to an operation of the traveling operation means, and a power supply control circuit disposed in the electric power supply control circuit And a delay circuit for cutting off the power supply to the electric motor from the battery after a predetermined time delay when cutting off the power supply from the battery to the electric motor. Drive controller.