JP2013032215A - Control device of working vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a control device of a working vehicle having an energy-saving constitution by reducing an energy loss in the working vehicle equipped with a hydraulic-driven working device.SOLUTION: The control device of a pole construction truck invalidates the setting operation of an accelerator pedal 66 when the operation start of an operation lever 64 is detected in a first lever position detector 101, limits the discharge flow rate of a second hydraulic pump P2 by rotating an electric motor 71 at the number of rotation of the predetermined value or smaller irrespective of the number of rotation subjected to the setting operation by the accelerator pedal 66, and variably adjusts the discharge flow rate of the second hydraulic pump P by validating the setting operation of the accelerator pedal 66 and controlling the number of rotation of the electric motor 71 according to the operating amount of the accelerator pedal 66 when detecting the operation for working the valve opening of control valves V1-V5 by the operation lever 64 substantially to the full condition in a second lever position detector 102.

Description

  The present invention relates to a control device for a work vehicle having a hydraulically driven work device on a vehicle body.

  A work vehicle generally uses a chassis such as a cab-over truck as a base vehicle, and a hydraulically driven work device and a power source for operating the work device are provided on a vehicle body. In such a work vehicle, as a method of operating the work device provided on the vehicle body, the power taken out from the power take-off mechanism (PTO) attached to the transmission by driving the traveling engine of the work vehicle. It is generally known that a hydraulic pump is driven by using a hydraulic pump and a working device is operated by hydraulic oil discharged from the hydraulic pump (see, for example, Patent Document 1).

  An example of the work vehicle as described above is a digging pillar car used for electrical, communication, civil engineering, and the like (see, for example, Patent Document 2). This drilling column car is provided with a boom that can freely move up and down, extend and retract, and turn on a vehicle body that can travel, and a drilling device called an earth auger device is attached to the tip of this boom, To build a utility pole or the like on the ground by moving the earth auger device above the excavation position by rotating the boom up and down, expanding or contracting or turning, and rotating the auger screw attached to the lower part of the earth auger device It is now possible to excavate building pillar holes. In addition, the digging column car is equipped with a winch device that winds and lowers a wire rope with a hook attached to the tip, and the electric pole is attached to the hook drawn out from the winch device and suspended from the tip of the boom. By hooking and suspending a rope that has been tied up, a utility pole can be installed in the excavated building pillar hole. In this way, the digging pillar car can efficiently perform the pillar work with a single work vehicle.

  In such a digging column car, the boom up / down motion, telescopic motion, turning motion, the winch device hoisting / lowering operation, and the earth auger device rotating operation are provided in the operation seat on the vehicle body. This is done by the operator operating each of the control levers. Each operation lever is connected to a control valve arranged corresponding to each hydraulic actuator of a working device such as a boom, and when the operator operates the operation lever, the hydraulic oil discharged from the hydraulic pump is Supply / discharge control is performed with the valve opening of the control valve in accordance with the operation amount, whereby each hydraulic actuator is operated.

  Separately from this, an accelerator pedal that the operator steps on is provided in the operation seat, and the engine speed as the power source of the hydraulic pump is controlled according to the operation amount of the accelerator pedal, and the engine rotation A configuration is also known in which hydraulic oil having a discharge flow rate corresponding to the number is supplied from a hydraulic pump to a hydraulic actuator (see, for example, Patent Document 3).

JP 2003-12297 A JP 2009-227390 A Japanese Patent No. 3330908

  Conventionally, in order to adjust the operating speed when operating a working device such as a boom, first, the hydraulic pedal is set in a state in which the accelerator pedal is fully depressed to a mechanical maximum stroke position (so-called solid stepped state). This is done by setting the discharge flow rate to the maximum flow rate, then adjusting the valve opening of the control valve based on the operation of the operation lever, and supplying hydraulic oil at a flow rate corresponding to this valve opening to the hydraulic actuator of the work device. It was. However, even when a large amount of hydraulic fluid is discharged from the hydraulic pump in this way, when the operation amount of the operation lever is relatively small, that is, when the valve opening of the control valve is small, the hydraulic pump discharges it. There is a problem that a considerable amount of hydraulic oil is wasted and returned to the oil tank without being used via a relief valve or the like in the hydraulic circuit, resulting in an increase in energy loss.

  The present invention has been made in view of such a problem, and provides a work vehicle control device configured to reduce energy loss and save energy in a work vehicle equipped with a hydraulically driven work device. The purpose is to provide.

  In order to solve the above problems, a control device for a work vehicle according to the present invention operates a vehicle body capable of traveling, a work device disposed on the vehicle body (for example, the boom 30 in the embodiment), and the work device. A hydraulic actuator (for example, the turning motor 23 in the embodiment), a power source (for example, the engine E or the battery unit 70 in the embodiment) provided on the vehicle body, and driven by receiving a rotational driving force from the power source. A hydraulic pump that discharges hydraulic oil to the actuator, an operating means for operating the work device (for example, the operating lever 64 in the embodiment), and a valve opening degree is changed according to the operation of the operating means to change the hydraulic pressure. A control valve for controlling the supply and discharge of hydraulic oil from the pump to the hydraulic actuator, and a first operation detection hand for detecting that the operation of the operation means has been started (For example, the lever position detector 101 in the embodiment) and second operation detection means for detecting that the operation means has operated the valve opening of the control valve to be fully opened (for example, the lever position in the embodiment). Detector 102), a rotational speed setting means (for example, an accelerator pedal 66 in the embodiment) for performing an operation of setting the rotational speed of the power source, and a rotational drive of the power source based on the rotational speed set in the rotational speed setting means. Power source control means (for example, the controller 80 in the embodiment) for controlling the motor. The power source control means invalidates the setting operation of the rotation speed setting means when the first operation detection means detects the start of operation of the operation means, and relates to the rotation speed set by the rotation speed setting means. When the operation for operating the valve opening of the control valve by the operating means to the fully open position is detected in the second operation detecting means by rotating the power source at a predetermined rotational speed or less to limit the discharge flow rate of the hydraulic pump. The setting operation of the rotation speed setting means is validated, and the rotation speed of the power source is controlled according to the operation amount of the rotation speed setting means, so that the discharge flow rate of the hydraulic pump can be variably adjusted.

In the above-described invention, the operation amount detection means for detecting the operation amount of the operation means stepwise is provided. It is preferable to change the rotational speed of the power source stepwise according to the operation amount of the setting means.

  Further, in the above-mentioned invention, it has a plurality of operation means for performing an operation to operate each of the plurality of work devices, each of the plurality of operation means is provided with a first operation detection means, When the operation start of two or more operation means is detected in the plurality of first operation detection means, the setting operation of the rotation speed setting means is validated, and the rotation speed of the power source according to the operation amount of the rotation speed setting means Is preferably controlled so that the discharge flow rate of the hydraulic pump can be variably adjusted.

  According to the control device for a work vehicle according to the present invention, the setting operation of the rotation speed setting means becomes valid in a state where the operation means is operated and the valve opening of the control valve is substantially fully opened. Since the hydraulic pump discharge flow rate is variably controlled according to the operation amount, and the amount of hydraulic oil discharged from the hydraulic pump to the hydraulic actuator is adjusted, the hydraulic pump discharge flow rate is maximized and the control valve valve Compared to the conventional technology where the required flow rate is adjusted by the opening, the surplus of hydraulic oil that exceeds the flow rate required for hydraulic actuator operation, that is, the amount of hydraulic oil that is released to the oil tank without being used is greatly increased. Therefore, it is possible to save energy by suppressing energy loss.

  In addition, energy efficiency can be increased without using a load sensing function (such as a pressure compensation valve) that controls the discharge flow rate of the hydraulic pump according to the differential pressure before and after the control valve. Reduction can be achieved. Further, since the energy loss is reduced as described above, the power consumption of the battery unit as a power source is reduced when applied to a battery-driven work vehicle. The operating time can be increased and the hydraulic pump can be operated for a long time, which in turn contributes to an improvement in work efficiency.

  The power source control means preferably changes the rotational speed of the power source stepwise according to the operation amount of the rotational speed setting means each time the operation amount of the operation means is detected by the operation amount detection means. According to such a configuration, finer control can be realized according to the operation amounts of the operation means and the rotation speed setting means, and workability can be further improved.

  Further, when the start of operation of two or more operation means is detected in the plurality of first operation detection means, the setting operation of the rotation speed setting means is validated, and the hydraulic pump is set according to the operation amount of the rotation speed setting means. It is preferable that the discharge flow rate can be variably adjusted. According to such a configuration, the pump speed can be arbitrarily controlled by the speed setting means when the two or more operating means are operated in an interlocked manner, and a plurality of work devices can be controlled. The hydraulic fluid can be supplied to each hydraulic actuator at a discharge flow rate sufficient to operate the actuators, preventing malfunction of the work equipment and improving the operability of the operating means. become.

It is a block diagram which shows the structure of the control apparatus which concerns on this invention. It is a side view which shows the digging pillar car provided with the said control apparatus. It is a top view of the said digging pillar car. It is a rear view of the said digging pillar car. It is a schematic diagram for demonstrating the tilting operation position of an operation lever. It is a graph which shows the relationship between the lever operation amount in the said control apparatus, a valve opening degree, and a pump discharge flow rate. It is a graph which shows the relationship between the lever operation amount in a prior art, a valve opening degree, and a pump discharge flow rate. It is a graph which shows the relationship between the lever operation amount in the modification of the said control apparatus, a valve opening degree, and a pump discharge flow rate.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. 2 to 4 show a battery-driven digging column 1 as an example of a work vehicle equipped with a control device according to the present invention. First, the entire digging column 1 is shown in FIG. An outline of the configuration will be described.

  The excavation column car 1 includes tire wheels 11, 11,..., A truck-type vehicle body 10 that can be driven and operated from the driving cab 12, a swivel base 20 provided on the vehicle body 10, and the turning A telescopic boom (hereinafter simply referred to as “boom”) 30 whose base end is pivotally attached to the base 20 so as to be swingable up and down, and a wire rope 42 that is attached to the base end side of the boom 30 and wound up. A winch device 40 that performs the lowering and an earth auger device 50 that is attached to the side of the boom 30 and that excavates the pillar hole are configured.

  The swivel base 20 is attached to the rear part of the vehicle body 10 so as to be able to rotate 360 degrees around the vertical axis. The swivel motor 23 built in the vehicle body 10 is hydraulically driven to perform a horizontal turn operation via a gear (not shown). Can do. The boom 30 has a configuration in which a proximal boom 30a, an intermediate boom 30b, and a distal boom 30c are assembled in a nested manner, and each boom 30a, 30b and 30c can be moved relatively, and the whole boom 30 can be expanded and contracted in the axial direction. Further, a hoisting cylinder 24 is straddled between the base end boom 30a and the swivel base 20, and the hoisting cylinder 24 as a whole can be hoisted within the upper and lower surfaces by hydraulically driving the hoisting cylinder 24. On the vehicle body 10, behind the driving cab 12, a boom rest 39 that protrudes upward is disposed so as to abut against the lower surface of the boom 30 that has fallen in a fully contracted state and store and hold the boom 30. Here, the boom 30 has a three-stage expansion / contraction configuration, but may have a two-stage or four-stage or more multi-stage expansion / contraction configuration.

  The winch device 40 is attached to the upper surface of the base end portion of the base end boom 30a, and the wire rope 42 fed out from the winch drum 41 is hung on a rotatable sheave (not shown) and below the front end boom 30c. And a hook (not shown) is attached to the tip. A winch motor 43 is provided at a side portion of the winch device 40. The winch motor 43 is hydraulically driven to wind and unwind the wire rope 42, thereby lifting and lowering the hook at the tip of the wire rope 42. Can be lowered. A wire guard 44 for protecting the wire rope 42 is disposed along the axial direction of the boom 30 at the upper end portion of the boom 30.

  The earth auger device 50 is attached to the boom 30 via an auger support frame 51 that can be selectively connected to the proximal boom 30a and the distal boom 30c. This earth auger device 50 includes an auger support arm 52 pivotally connected to an auger support frame 51, a base frame 53 attached to the auger support arm 52, and an auger motor 54 with a speed reducer attached to the tip of the base frame 53. And an auger screw 55 that is rotationally driven by hydraulically driving the auger motor 54. Further, an auger support device 56 that fixes and holds the earth auger device 50 in a retracted state is disposed on the side surface of the proximal boom 30a. The earth auger device 50 can swing up and down in a vertical plane around the auger support arm 52. More specifically, the earth auger device 50 is stored along the side of the proximal boom 30a by the auger storage device 56. The ground auger device 50 can be removed from the auger storage device 56, and the auger screw 55 can be swung between the storage position and the vertical position with respect to the ground.

  When the earth auger device 50 is used (that is, when excavating a pillar hole), the earth auger device 50 is swung to a lower working position, and the auger support frame 51 is connected and tied to the tip boom 30a. Let As a result, the earth auger device 50 can move to a desired position together with the tip boom 30c. Then, by driving the auger motor 54 and rotating the auger screw 55, the auger screw 55 (boom tip) is linearly moved downward by interlocking the falling movement and the reduction movement of the boom 30, so Excavation work is performed.

  On the other hand, when the earth auger device 50 is not used, the earth auger device 50 is swung to the storage position along the side of the proximal boom 30a with the boom 30 fully retracted and stored and held by the auger support device 56. At the same time, the auger support frame 51 is connected to the proximal boom 30a. In this state where the earth auger device 50 is retracted, the wire rope 42 can be wound and unwound by the winch device 40. In the following description, the swivel base 20, the boom 30, the winch device 40, and the earth auger device 50 are collectively referred to as “working device”.

  Further, a hydraulic pressure supply unit 90 that supplies hydraulic oil to the vehicle body 10 to the turning motor 23, the hoisting cylinder 24, the telescopic cylinder 31, the winch motor 43, and the auger motor 54 (hereinafter collectively referred to as “hydraulic actuator”). And a controller 80 for controlling the operation of the work device.

  Outrigger jacks 13 are provided at four positions on the front, rear, left and right of the vehicle body 10, and the vehicle body 10 can be supported in a lifted state during work by projecting the outrigger jacks 13 downward and grounding. In addition, each outrigger jack 13 can be projected to the side (vehicle width direction) of the vehicle body 10, thereby making the vehicle body 10 more stable. The operation of the outrigger jack 13 is performed by operating an outrigger operation device 14 provided at the rear of the vehicle body 10.

  An operation seat 60 for operating the work devices (the turntable 20, the boom 30, the winch device 40, and the earth auger device 50) is provided on the side of the turntable 20 in the vehicle body 10. The operation seat 60 is attached to a side portion of the swivel base 20 and pivoted together with the swivel base 20. The operation seat 60 is disposed on the upper side of the base board 61 so that the operator faces the distal end side of the boom 30. A sitting chair 62 and an operation device 63 positioned in front of the chair 62 are provided. An operator can access the operation device 63 while sitting on the chair 62.

  The operating device 63 includes a turning operation lever 64a for turning the swivel base 20, a raising / lowering operating lever 64b for raising and lowering the boom 30, an extendable operation lever 64c for extending and retracting the boom 30, and a winch. A winch operating lever 64d for performing the hoisting / lowering operation of the device 40 and an auger operating lever 64e for rotating the earth auger device 50 are provided, and these five operating levers 64 are provided in the operation seat 60. Are arranged side by side with a predetermined interval in the width direction. Adjacent to the turning operation lever 64a, an attachment operation lever 65 is provided for performing an operation of pulling out a utility pole by a drawing machine (not shown) and an operation of an attachment to be attached as an option (hereinafter referred to as an operation lever 65). The description of the operation lever 65 is omitted, and the illustration of the operation lever 65 is also omitted in FIG. 1, but the operation lever 65 can also be applied as an operation means defined in the claims).

  Each operation lever 64 can be tilted from the neutral position slightly tilted rearward when viewed from the operator toward the front (boom tip side) and the rear (worker side). For example, by turning the turning operation lever 64a forward, the turning motor 23 is driven to rotate in one direction to turn the turntable 20 in the counterclockwise direction, and by turning backward, the turning motor 23 is moved in the other direction. To rotate the swivel base 20 in the clockwise direction. Further, the hoisting operation lever 64b is tilted forward when viewed from the operator, the hoisting cylinder 24 is contracted to perform the tilting operation of the boom 30, and the hoisting cylinder 24 is extended by the tilting operation backward. The boom 30 is lifted up. Further, the telescopic operation lever 64c is tilted forward to cause the telescopic cylinder 31 to extend to operate the boom 30, and the rearward tilt is operated to contract the telescopic cylinder 31 to reduce the boom 30. Activate. Further, the winch operation lever 64d is tilted forward to rotate the winch motor 43 in one direction to cause the wire rope 42 to be wound down, and tilted backward to rotate the winch motor 43 in the other direction. The wire rope 42 is wound up by driving. Further, the auger operation lever 64e is tilted forward to rotate the auger motor 54 in one direction to rotate the auger screw 55 in the reverse direction, and the auger operation lever 64e is tilted backward to move the auger motor 54 in the other direction. The auger screw 55 is rotated in the forward direction.

  As shown in FIG. 1, the swing motor 23 is routed through the first control valve, the hoisting cylinder 24 is routed through the second control valve V2, the telescopic cylinder 31 is routed through the third control valve V3, and the winch motor 43 is routed. The hydraulic oil (pressure oil) selectively discharged by the first hydraulic pump P1 or the second hydraulic pump P2 of the hydraulic pressure supply unit 90 via the fourth control valve V4 and to the auger motor 54 via the fifth control valve V5. It comes to be supplied.

  Each of the control valves V1 to V5 is a manual valve that is mechanically coupled to each operation lever 64, so that the operator can directly adjust the valve opening. Each control valve V1 to V5 changes the valve opening degree by driving the spool with a drive direction and a drive amount corresponding to the operation direction and the tilting operation amount from the neutral position of each operation lever 64. The drive direction of each spool of the control valves V1 to V5 is related to the drive direction (extension / contraction direction or rotation direction) of the corresponding hydraulic actuator, and the drive amount (valve opening) of each spool is an operation supplied to the corresponding hydraulic actuator. This is related to the flow rate of oil (flow rate per unit time), that is, the driving speed of the hydraulic actuator.

  In addition, an accelerator pedal 66 is provided on the floor surface of the base substrate 61 in the operation seat 60 so that an operator sitting on a chair 62 can operate by stepping on with his / her foot. The amount of depression of the accelerator pedal 66 is detected by an accelerator operation amount detector 67 (for example, composed of a potentiometer, an encoder, etc.), and an accelerator signal corresponding to the amount of depression is output to the controller 80. The controller 80 receives the accelerator signal from the accelerator operation amount detector 67, and controls the operation of the power source of the hydraulic pumps P1 and P2 (details will be described later).

  In this digging pillar work vehicle 1, a traveling engine E provided at the lower part of the vehicle body 10 is used as a power source for the first hydraulic pump P1, and the vehicle is provided on the vehicle body 10 as a power source for the second hydraulic pump P2. The engine unit E, the battery unit 70, the controller 80, the hydraulic pressure supply unit 90, and the like are provided as an operating mechanism of a work device (hydraulic actuator) such as the boom 30.

  As shown in FIG. 1, the power of the engine E is shifted by a transmission TM and transmitted to the tire wheel 11 via a propeller shaft (not shown). The transmission TM includes a power take-off mechanism PTO. When an operation (on operation) is performed to displace the PTO operation lever 15 in the driving cab 12 from the off position to the on position, the power take-off mechanism PTO By actuating the mechanism unit, the drive destination of the engine E can be switched from the tire wheel 11 to the first hydraulic pump P1. A PTO switch 16 is provided in the vicinity of the PTO operation lever 15. When the PTO operation lever 15 is turned on, the PTO switch 16 is turned on to detect the state of taking out the power of the engine E. The

  The engine E is connected to an electronic control unit ECU that controls each part of the engine. The electronic control unit ECU performs throttle opening control, fuel injection control, and the like of the engine E to control the rotational speed of the engine E (that is, the rotational speed of the first hydraulic pump P1 connected thereto). 1 Controls the discharge flow rate (and discharge pressure) of hydraulic oil discharged from the hydraulic pump P1.

  The battery unit 70 receives an electric motor 71 connected to the second hydraulic pump P2, a body part battery 72 that stores electric power for driving the electric motor 71, and power supplied from the body part battery 72. And a motor control device 73 for controlling the operation of the electric motor 71.

  The body part battery 72 is composed of a plurality of power supply batteries, and each power supply battery is connected in series with each other, for example, with a predetermined voltage of 48 [V] and sufficient electric power to perform the work for one day. This is a DC power supply capable of charging and holding the capacity 280 [Ahr]. This body part battery 72 is connected to a charger (not shown) provided at the lower part of the vehicle body 10, and the power plug of this charger is connected to a power outlet of a sales office or the like, thereby The three-phase AC power supplied from the plug is converted into a direct current of a predetermined voltage and supplied to the body part battery 72 to charge each power source battery of the body part battery 72.

  The motor control device 73 is configured by, for example, a control circuit using an inverter control system, and converts the direct current power supplied from the bodywork battery 72 into alternating current power having a voltage value corresponding to a command signal from the controller 80. 71, and controls the rotational speed of the electric motor 71 (that is, the rotational speed of the second hydraulic pump P2 connected thereto) to discharge the hydraulic oil discharged from the second hydraulic pump P2 (and the discharge flow). Pressure).

  The controller 80 is turned on and off via a power supply circuit 81 provided on the vehicle body 10. The power supply circuit 81 includes the above-described PTO switch 16 that closes (turns on) the switch contact based on the operation of the PTO operation lever 15, and the PTO switch is operated when the PTO operation lever 15 is turned on. When the switch contact of 16 is closed, the controller 80 is connected to the chassis battery 17 for running control that supplies power to the vehicle-side electrical device such as the engine E, and the controller 80 is turned on. It is configured to be. The chassis battery 17 is connected to a generator (for example, an alternator) that generates electric power by rotating the engine E, and is charged by supplying the generated electric power.

  In addition, the motor control device 73 is electrically connected to the chassis battery 17 via a power switch 68 provided on the operation seat 60 and capable of being turned on / off. Electric power is supplied from the battery 17 to the motor control device 73, and the motor control device 73 is turned on.

  The hydraulic pressure supply unit 90 includes an oil tank T that stores a predetermined amount of hydraulic oil, a mechanical first hydraulic pump P1 that is driven by the power of the engine E taken out by the power take-off mechanism PTO, and an electric motor in the battery unit 70. The mechanical second hydraulic pump P2 driven by the power of the motor 71 and the control valves (manual valves) V1 to V5 mechanically connected to the operation levers 64 are provided. Thus, the hydraulic pressure supply unit 90 is provided with two hydraulic pumps P1 and P2 for operating the working device (hydraulic actuator), and a power source selection switch (toggle switch) 69 described later provided in the operation device 63 is provided. Either one is selectively driven in accordance with the operation position, and the hydraulic oil is sucked up from the oil tank T by the first hydraulic pump P1 or the second hydraulic pump P2, and the control valves V1 to V5. Are discharged and supplied to each hydraulic actuator. A relief valve (not shown) and a check valve (not shown) are interposed on the oil passages between the hydraulic pumps P1 and P2 and the control valves V1 to V5.

  The power source selection switch 69 is constituted by, for example, a toggle switch that can be tilted to any one of the front and rear positions, and the work device (hydraulic actuator) is moved from the first hydraulic pump P1 according to the tilt position. It can be selected whether to drive with the supplied hydraulic oil or to drive with the hydraulic oil supplied from the second hydraulic pump P2. In the power source selection switch 69, when both the PTO switch 16 and the power switch 68 are turned on, that is, when both the first hydraulic pump P1 and the second hydraulic pump P2 can be driven. The selection is valid only.

  In the digging column 1 constructed as described above, the two power sources are selectively controlled, and the hydraulic pump P1 is based on the tilting operation amount of each operation lever 64 and the depression operation amount of the accelerator pedal 66. , P2 is provided with a control device for variably adjusting the discharge flow rate. The configuration of this control apparatus will be described below with additional reference to FIGS.

  The control device according to the present embodiment includes the hydraulic actuator, the operation lever 64, the accelerator pedal 66, the accelerator operation amount detector 67, the engine E, the battery unit 70, the controller 80, the hydraulic supply unit 90, and the power source selection switch 69 described above. In addition, the lever position detectors 100 and 101 are provided.

  The first lever position detector 101 is composed of, for example, a limit switch. As the operation position of the operation lever 64, the operation lever 64 is tilted even slightly from the neutral position A, that is, the operation lever 64 is started to operate. (This detection position is referred to as “lever operation detection position B”). The lever position detector 101 is turned on when the operation lever 64 reaches the lever operation detection position B, and outputs an on signal to the controller 80 electrically connected to the detector 101. Here, as the lever operation detection position B, for example, a neutral position (non-operation position) A where the operation lever 64 is not operated, and the operation of the mechanical control valves V1 to V5 when the operation lever 64 is operated by a predetermined angle. Is set within a range of play with respect to an operation start position (valve opening = 0 in FIG. 6).

  The second lever position detector 102 includes, for example, a limit switch, and detects that the operation lever 64 has been operated to the vicinity of the maximum tilt position (full lever position) D as the operation position of the operation lever 64 (this detection position). Is referred to as “lever maximum detection position C”). The lever position detector 102 is turned on when the operation lever 64 reaches the lever maximum detection position C, and outputs an on signal to the controller 80 electrically connected to the detector 102.

  As described above, each operation lever 64 can be tilted in the front-rear direction, and each operation lever 64 includes first and second lever position detectors 101 and 102 for detecting a front operation, and a rear operation. Although the first and second lever position detectors 101 and 102 for detection are provided (that is, two sets of front and rear are provided), in FIG. One position detector 101 and one second lever position detector 102 are shown.

  When the controller 80 determines that the operation lever 64 has reached the lever operation detection position B based on the on / off signals from the first and second lever position detectors 101 and 102, that is, the first lever. When the signal output from the position detector 101 is an on signal and the output signal from the second lever position detector 102 is an off signal, the operation of the accelerator pedal 66 is invalidated. After invalidating the operation of the accelerator pedal 66 as described above, the controller 80 detects the accelerator detected by the accelerator operation amount detector 67 when the power source selection switch 69 is selected to the engine E side. Regardless of the amount of operation of the pedal 66 (whether the accelerator pedal 66 is operated), the engine E is controlled to a constant low speed through the electronic control unit ECU, and the hydraulic actuator is operated with the discharge flow rate of the first hydraulic pump P1. The flow rate is limited to the minimum flow rate Qs (a constant small flow rate) necessary for the control. On the other hand, when the power source selection switch 69 is selected on the battery unit 70 side, the controller 80 passes through the motor control device 73 regardless of the operation amount of the accelerator pedal 66 (whether or not the accelerator pedal 66 is operated). Thus, the electric motor 71 is controlled to a constant low speed, and the discharge flow rate of the second hydraulic pump P2 is limited to the minimum flow rate Qs.

  Therefore, in this state, the operation of the accelerator pedal 66 is invalidated. Therefore, no matter how much the accelerator pedal 66 is depressed, the engine E or the electric motor 71 is maintained at a constant low speed, and the first hydraulic pump P1 or the second The discharge flow rate of the hydraulic pump P2 is always limited to a certain minimum flow rate Qs, and the flow rate (secondary flow rate) according to the valve opening of the control valves V1 to V5 is limited to the minimum flow rate Qs (primary flow rate) to the hydraulic actuator. Supplied in.

  When the controller 80 detects that the operating lever 64 has reached the lever maximum detection position C based on the on / off signals from the first and second lever position detectors 101 and 102, that is, the first When the output signal from the lever position detector 101 and the output signal from the second lever position detector 102 are both ON signals, the operation of the accelerator pedal 66 is effectively switched. In this way, after the operation of the accelerator pedal 66 is validated, the controller 80, when the power source selection switch 69 is selected to the engine E side, the target rotational speed corresponding to the operation amount of the accelerator pedal 66. Thus, by controlling the rotational speed of the engine E, the discharge flow rate of the first hydraulic pump P1 is variably controlled according to the rotational speed (target rotational speed) of the engine E. On the other hand, when the power source selection switch 69 is selected on the battery unit 70 side, the controller 80 controls the rotation speed of the electric motor 71 with the target rotation speed corresponding to the operation amount of the accelerator pedal 66. The discharge flow rate of the second hydraulic pump P2 is variably controlled according to the rotational speed (target rotational speed) of the electric motor 71. Here, the number of revolutions of the engine E or the battery unit 70 (electric motor 71) may be controlled stepwise according to the depression operation amount of the accelerator pedal 66, or may be controlled continuously.

  In this state, when the accelerator pedal 66 is fully depressed (so-called solid pedal operation), the discharge flow rates of the hydraulic pumps P1 and P2 become the maximum flow rate Qm, and the control valves V1 to V5 are fully opened. Thus, the discharge flow rates of the hydraulic pumps P1 and P2 can be increased or decreased between the minimum flow rate Qs and the maximum flow rate Qm according to the operation amount of the accelerator pedal 66, and supplied to the hydraulic actuator (here, the primary flow rate and the second flow rate). The next flow rate is almost the same).

  On the other hand, when excavating the pillar hole, etc., the boom 30 is tilted and contracted (the hoisting cylinder 24 and the expansion / contraction) while rotating the auger screw 55 of the earth auger device 50 (rotatingly driving the auger motor 54). Since it is necessary to move the auger screw 55 linearly downward in conjunction with the expansion / contraction operation of the cylinder 31, there are many scenes in which a plurality of operation levers 64 are operated in conjunction. However, when the operation amounts of the plurality of operation levers 64 that are operated in an interlocked manner are all small (for example, an operation amount that exceeds the lever operation detection position B), and the hydraulic actuators are operated in an interlocked manner at a slow speed, the hydraulic pressure Since the discharge flow rates of the pumps P1 and P2 are always limited to a certain minimum flow rate Qs, the amount of hydraulic oil discharged and supplied from the hydraulic pumps P1 and P2 to the plurality of hydraulic actuators is insufficient, and the operability is deteriorated. (Sometimes a malfunction occurs). Therefore, when the controller 80 detects that a plurality of (two or more) operation levers 64 have reached the lever operation detection position B based on output signals from the plurality of first lever position detectors 101. That is, when the OFF signals are simultaneously received from the plurality of lever position detectors 101, the operation of the accelerator pedal 66 is effectively switched, and the driving source (engine E or electric motor 71) is controlled by the accelerator pedal 66 as described above. The rotational speed can be made variable, that is, the discharge flow rates of the hydraulic pumps P1 and P2 can be variably adjusted. Accordingly, the amount of hydraulic oil supplied to the plurality of hydraulic actuators by appropriately changing the amount of hydraulic oil necessary for operating the plurality of work devices from the minimum flow rate Qs to the maximum flow rate Qm by operating the accelerator pedal 66. We are trying to secure enough.

  In the excavation column car 1 equipped with the control device configured as described above, in order to perform a desired work (for example, a pole work of an electric pole), the work vehicle is driven and arrives at a target work site. The operator who has performed the operation of the PTO operation lever 15 first in the operating state of the engine E. As a result, the first hydraulic pump P1 can be driven to rotate by receiving the power of the engine E taken out by the power take-off mechanism PTO, and the PTO switch 16 is turned on so that the chassis battery 17 transfers to the controller 80. Power is supplied and the controller 80 is turned on. Further, when the operator turns on the power switch 68 of the operation seat 60, electric power is supplied from the chassis battery 17 to the motor control device 73 of the battery unit 70, and the power of the motor control device 73 is turned on. 2 The hydraulic pump P2 is in a state where it can be rotationally driven by the electric motor 71 driven by receiving power supply from the battery unit 70.

  Thus, when both the first hydraulic pump P1 and the second hydraulic pump P2 can be driven to rotate, the power source selection switch 69 can select which hydraulic pump P1, P2 supplies hydraulic fluid. The hydraulic oil stored in the oil tank T is sucked up by the first hydraulic pump P1 or the second hydraulic pump P2 and supplied to the control valves V1 to V5 according to the operation amount of each operation lever 64. The supply / discharge control is performed at the valve opening and the hydraulic actuators are supplied.

  Next, the control contents of the control device when operating the operation lever 64 to activate the work device will be described. Here, a case where only one of the five operation levers 64 provided in the operation seat 60 is operated alone will be described as an example. In the following description, a case where the battery unit 70 is used as a power source will be described, but it goes without saying that the engine E may be used as a power source.

  First, when the operation lever 64 is not operated and is in the neutral position A, the control valves V1 to V5 are fully closed, and the output signals from the first and second lever position detectors 101 and 102 are both off. Signal. At this time, the controller 80 does not output a motor drive signal to the motor control device 73 of the battery unit 70, and hydraulic fluid is not supplied from the second hydraulic pump P2 to the hydraulic actuator.

  When it is detected that the tilting operation of the operation lever 64 is started and the lever operation detection position B is reached, that is, the output signal from the first lever position detector 101 is an ON signal, and the second lever position When the output signal from the detector 102 is an off signal, the controller 80 invalidates the operation of the accelerator pedal 66 and outputs a low-speed rotation signal as a motor drive signal to the motor control device 73 of the battery unit 70. The electric motor 71 is driven at a low speed and constant rotation. In response to the rotational driving force of the electric motor 71, the second hydraulic pump P2 is rotationally driven at a constant low speed, and the discharge flow rate of the second hydraulic pump P2 is limited to a certain minimum flow rate Qs regardless of the operation amount of the accelerator pedal 66. Is discharged.

  Here, until the valve opening degree of the control valves V1 to V5 reaches a predetermined opening degree, the hydraulic oil with the minimum flow rate Qs discharged from the second hydraulic pump P2 has a flow rate corresponding to the valve opening degree to the hydraulic actuator. On the other hand, a part of the flow rate (the hatched portion in FIG. 6) that has not been supplied to the hydraulic actuator is returned to the oil tank T via a relief valve or the like in the hydraulic circuit.

  On the other hand, when the operation lever 64 is further tilted and the valve openings of the control valves V1 to V5 become a predetermined opening or more, the total amount of the fixed flow rate Qs discharged from the second hydraulic pump P2 is passed through the control valves V1 to V5. Supplied to the hydraulic actuator. Here, the valve openings of the control valves V1 to V5 change linearly according to the operation amount of the operation lever 64. In this state, the discharge flow rate from the second hydraulic pump P2 is the operation lever 64 and the accelerator pedal. The hydraulic actuator (working apparatus) operates at a constant low speed corresponding to the flow rate of the hydraulic oil, since it is always constant (fixed flow rate Qs) regardless of the operation amount of 66.

  When it is detected that the operation lever 64 is further tilted to reach the lever maximum detection position C, that is, the output signals from the first and second lever position detectors 101 and 102 are both ON signals. In some cases, the operation of the accelerator pedal 66 is switched from invalid to valid by the controller 80, and a motor control signal corresponding to the operation amount of the accelerator pedal 66 detected by the accelerator operation amount detector 67 is output to the motor control device 73. Then, the rotational drive of the electric motor 71 is controlled at the target rotational speed corresponding to the operation amount. As a result, the hydraulic oil is supplied to the hydraulic actuator with the discharge flow rate corresponding to the rotation speed (target rotation speed) of the electric motor 71 while the control valves V1 to V5 are substantially fully opened. In this state, the operator can operate the accelerator pedal 66 to adjust the discharge flow rate of the second hydraulic pump P2, that is, to adjust the flow rate of the hydraulic oil supplied to the hydraulic actuator. Thus, the operating speed of the working device (hydraulic actuator) can be arbitrarily changed. Here, the control valves V1 to V5 always maintain a substantially fully opened state, and the total amount of hydraulic fluid discharged from the second hydraulic pump P2 is controlled by the control valves V1 to V5 regardless of increase or decrease of the discharge flow rate of the second hydraulic pump P2. (The primary flow rate from the second hydraulic pump P2 is directly introduced into the hydraulic actuator as a secondary flow rate), so that the relief loss returned to the oil tank T is reduced and energy efficiency is improved. Enhanced.

  For reference, in the prior art in which the discharge flow rate of the hydraulic pumps P1 and P2 is maximized and the required flow rate is adjusted by the valve openings of the control valves V1 to V5, all the hatched portions shown in the graph in FIG. This corresponds to energy loss (that is, energy use efficiency is poor). On the other hand, in the control device of the present embodiment, the hydraulic oil discharged from the hydraulic pumps P1 and P2 through the above process returns to the oil tank T without being used, that is, the portion corresponding to the energy loss. Is only the shaded portion shown in the graph in FIG. 6, and it can be seen that the energy loss is extremely reduced.

  In the above description, only one of the five operation levers 64 is operated alone. However, two or more operation levers 64 are operated in conjunction with each other. In this case, when it is detected that the two or more operation levers 64 have reached the lever operation detection position B based on output signals from the plurality of first lever position detectors 101 (a plurality of levers When the OFF signal is simultaneously received from the position detector 101), the operation of the accelerator pedal 66 is effectively switched, and the rotation speed of the drive source (engine E or electric motor 71) is made variable by the accelerator pedal 66, that is, The discharge flow rate of the hydraulic pumps P1 and P2 can be variably adjusted. Accordingly, the amount of hydraulic oil supplied to the plurality of hydraulic actuators is sufficiently increased by appropriately increasing or decreasing the discharge flow rate of the hydraulic pumps P1 and P2 between the minimum flow rate Qs and the maximum flow rate Qm according to the operation amount of the accelerator pedal 66. Can be secured.

  As described above, in the control device for the digging column car 1 according to the present embodiment, the operation of the accelerator pedal 66 is effective in a state where the operation lever 64 is tilted and the valve openings of the control valves V1 to V5 are substantially fully opened. Since the discharge flow rate of the hydraulic pumps P1 and P2 is variably controlled according to the amount of depression of the accelerator pedal 66, the amount of hydraulic oil discharged and supplied from the hydraulic pumps P1 and P2 to the hydraulic actuator is adjusted. Compared with the prior art in which the required flow rate is adjusted by the valve opening of the control valves V1 to V5 by maximizing the discharge flow rate of the hydraulic pumps P1 and P2, the hydraulic oil exceeds the flow rate necessary for the operation of the hydraulic actuator. The amount of hydraulic oil that is relieved to the oil tank T without being used, that is, the amount of hydraulic oil that is not used, can be greatly reduced. Possible it is.

  In addition, energy efficiency can be increased without using a load sensing function (such as a pressure compensation valve) that controls the discharge flow rate of the hydraulic pump according to the differential pressure before and after the control valve. Reduction can be achieved.

  Furthermore, since the energy loss is reduced as described above, in the battery-driven digging column car 1, the power consumption of the battery unit 70 serving as a power source is reduced. The operating time of 70 can be increased and the hydraulic pumps P1 and P2 can be operated for a long time, which in turn contributes to an improvement in work efficiency.

  Further, when the start of operation of two or more operation levers 64 is detected in the plurality of first lever position detectors 101, the operation of the accelerator pedal 66 is validated, and the hydraulic pump according to the operation amount of the accelerator pedal 66 The discharge flow rates of P1 and P2 can be variably adjusted. Accordingly, when the two or more operation levers 64 are operated in an interlocking manner, the number of revolutions of the pump can be arbitrarily controlled by the accelerator pedal 66, and hydraulic oil having a discharge flow rate sufficient to operate the plurality of working devices in an interlocking manner is supplied to each hydraulic actuator. Since it can be supplied, it is possible to prevent malfunctions of work devices such as the boom 30 and the earth auger device 50 and to improve the interlocking operability of the operation lever 64.

  By the way, in the above-described embodiment, only when it is detected that the operation lever 64 has been operated to the lever maximum detection position C, the operation of the accelerator pedal 66 is made effective and the engine E according to the operation amount of the accelerator pedal 66. Alternatively, the number of rotations of the electric motor 71 is changed. As a modification of the present embodiment, a lever operation amount detection means (not shown) configured to detect the operation amount of the operation lever 64 stepwise is used. Each time the operation amount of the operation lever 64 is detected by the lever operation amount detection means, the rotational speed of the engine E or the electric motor 71 is changed stepwise according to the operation amount of the accelerator pedal 66. You may comprise. Briefly describing this modification, the lever operation amount detection means detects the operation amount after the operation lever 64 exceeds the lever operation detection position B in three stages (operation amounts S1, S2, S3 in FIG. 8). And a detection signal is output to the controller 80 each time the manipulated variables S1, S2, S3 are detected. Whenever the controller 80 receives a detection signal from the lever operation amount detection means, the controller 80 validates the operation of the accelerator pedal 66 and rotates the engine E or the electric motor 71 at a target rotational speed corresponding to the operation amount of the accelerator pedal 66. The number is changed, and the discharge flow rate of the first hydraulic pump P1 or the second hydraulic pump P2 is variably adjusted.

  Here, FIG. 8 is a graph showing the relationship between the lever operation amount, the valve opening degree, and the pump discharge flow rate in the modification of the present embodiment. First, when the operation amount S1 of the operation lever 64 is detected, the operator can change the discharge flow rate of the hydraulic pumps P1 and P2 from the minimum flow rate Qs to the flow rate Q1 according to the operation amount of the accelerator pedal 66 by his own pedal operation. The hydraulic oil can be supplied to the hydraulic actuator at a valve opening degree corresponding to the operation amount of the operation lever 64. Subsequently, when the operation lever 64 is further tilted and the operation amount S2 is detected, the operator minimizes the discharge flow rate of the hydraulic pumps P1 and P2 according to the operation amount of the accelerator pedal 66 by his own pedal operation. The hydraulic oil can be supplied to the hydraulic actuator at a valve opening degree corresponding to the operation amount of the operation lever 64 by increasing or decreasing between the flow rate Qs and the flow rate Q2. Next, when the operation amount S3 of the operation lever 64 is detected, the operator can change the discharge flow rate of the hydraulic pumps P1 and P2 from the minimum flow rate Qs to the maximum flow rate Qm according to the operation amount of the accelerator pedal 66 by his own pedal operation. The hydraulic oil can be supplied to the hydraulic actuator at a valve opening corresponding to the operation amount of the operation lever 64. Thus, every time the operation amount of the operation lever 64 is detected stepwise, the discharge flow rates of the hydraulic pumps P1, P2 that can be adjusted by the accelerator pedal 66 also increase stepwise. Fine control is possible according to the amount of operation of the accelerator pedal 66. When it is detected that the operation lever 64 has reached the lever maximum detection position C, as described above, the hydraulic pumps P1, P1 and P2 correspond to the operation amount of the accelerator pedal 66 with the valve opening being substantially fully opened. The total amount of hydraulic oil discharged from P2 can be supplied to the hydraulic actuator.

  In the graph of FIG. 8, the shaded portion corresponds to the energy loss, and it can be seen that the energy loss is also reduced in this modified example as compared with the prior art (graph in FIG. 7). Therefore, according to such a configuration, energy loss can be suppressed and energy saving can be achieved, and finer control can be realized according to the operation amount of the operation lever 64 and the accelerator pedal 66, and It is possible to further improve the performance.

  The preferred embodiments of the present invention have been described so far, but the scope of the present invention is not limited to those shown in the above-described embodiments. For example, the lever position detectors 101 and 102 have been illustrated and described as the operation detection unit of the operation lever 64. However, the operation detection unit may be detected based on either the operation amount or the operation position of the operation lever 64. In the above-described embodiment, the lever position detector is configured by a limit switch. However, the present invention is not limited to this, and other optical or mechanical types (non-contact operation type or contact operation type) It is also possible to use other detectors.

  Further, in the above-described embodiment, the case where the control valves V1 to V5 are configured by manual valves that are mechanically connected and interlocked with the operation lever 64 is described as an example. However, the present invention is not limited to this. The valves V1 to V5 may be constituted by electromagnetic valves (proportional electromagnetic directional flow control valves), and the controller may drive the spool of the control valve based on an operation signal output by operating the operation lever. Furthermore, in the above-described embodiment, the valve openings of the control valves V1 to V5 change continuously (linearly), but the valve openings may change stepwise (at least in two steps).

  Moreover, in the above-described embodiment, the case where the operation means is configured by an operation lever that is tiltable in the front-rear direction is illustrated, but the present invention is not limited to this, and an operation lever that is tiltable in the left-right direction is used. In addition, a joystick-type operation lever that can be tilted in multiple directions and twisted around an axis, a position lever that can be selectively operated at a plurality of preset positions, You may comprise a volume switch etc. which can be operated dynamically.

  In the above-described embodiment, when it is detected that the operation lever 64 has reached the lever operation detection position B, the rotation speed of the engine E or the rotation speed of the electric motor 71 is controlled to a predetermined low speed constant rotation. The case where the discharge flow rates of the hydraulic pumps P1 and P2 are always limited to a constant minimum flow rate Qs has been described as an example, but the present invention is not limited to this, and the rotation speed of the engine E or the rotation speed of the electric motor 71 It may be variably controlled according to the amount of tilting operation of the operation lever 64 until the predetermined rotational speed is reached, and may be controlled to constant speed rotation when the predetermined rotational speed is reached. Note that the discharge flow rates of the hydraulic pumps P1 and P2 at this time are not limited to the minimum flow rate Qs, and can be appropriately adjusted in consideration of the torque necessary for operating the working device.

  Further, in the above-described embodiment, the object to which the present invention is applied is a work vehicle whose body is a tire wheel type, but the vehicle body is not necessarily limited to a tire wheel type, and travels by a crawler device or the like. It may be a thing. Alternatively, it may be an orbital working vehicle that includes an orbital traveling wheel and travels on an orbital track, and further, an orbital working vehicle that includes both a tire wheel and an orbital traveling wheel.

  In the above-described embodiment, the battery-driven work vehicle that selectively operates the power of the engine E or the battery unit 70 to operate the work device has been described. However, the present invention is not limited to this. For example, a work vehicle that operates the work device only with the power of the engine E, or a work vehicle that operates the work device only with the power of the battery unit 70 may be used. Furthermore, in the above-described embodiment, the digging pillar car is illustrated and described as the work vehicle according to the present invention, but is not limited to this, for example, an aerial work vehicle, a railroad vehicle, a crane vehicle, etc. The present invention can be applied to other work vehicles.

1 Drilling column car (work vehicle)
10 body 20 swivel (working device)
23 Swing motor (hydraulic actuator)
24 Rolling cylinder (hydraulic actuator)
30 Boom (Working device)
31 Telescopic cylinder (hydraulic actuator)
40 Winch device (working device)
43 Winch motor (hydraulic actuator)
50 Earth auger device (working device)
54 Auger motor (hydraulic actuator)
64 Operation lever (operation means)
66 Accelerator pedal (speed setting means)
70 Battery unit (power source)
71 Electric motor 72 Bodywork battery 73 Motor controller 80 Controller (power source control means)
90 Hydraulic supply unit 101 First lever position detector (first operation detecting means)
102 2nd lever position detector (2nd operation detection means)
E Engine (Power source)
V control valve P1 1st hydraulic pump (hydraulic pump)
P2 Second hydraulic pump (hydraulic pump)

Claims (3)

A vehicle body that can travel,
A working device disposed on the vehicle body;
A hydraulic actuator for operating the working device;
A power source provided on the vehicle body;
A hydraulic pump driven by receiving a rotational driving force from the power source, and supplying hydraulic oil to the hydraulic actuator;
Operation means for performing an operation for operating the working device;
A control valve that controls the supply and discharge of hydraulic fluid from the hydraulic pump to the hydraulic actuator by changing the valve opening according to the operation of the operating means;
First operation detecting means for detecting that the operation of the operating means has started;
Second operation detecting means for detecting that the operating means has been operated to operate the valve opening of the control valve to substantially fully open;
A rotational speed setting means for performing an operation of setting the rotational speed of the power source;
Power source control means for controlling the rotational drive of the power source based on the rotational speed set in the rotational speed setting means,
The power source control means disables the setting operation of the rotation speed setting means when the first operation detection means detects the start of operation of the operation means, and sets the rotation set by the rotation speed setting means. Regardless of the number, the power source is rotationally driven at a predetermined rotational speed or less to limit the discharge flow rate of the hydraulic pump, and the second operation detecting means operates the valve opening of the control valve by the operating means to substantially fully open. When the operation to be performed is detected, the setting operation of the rotation speed setting means is validated, the rotation speed of the power source is controlled according to the operation amount of the rotation speed setting means, and the discharge flow rate of the hydraulic pump A control device for a work vehicle, characterized in that the vehicle can be variably adjusted. An operation amount detection means for detecting the operation amount of the operation means stepwise;
The power source control means changes the rotational speed of the power source stepwise according to the operation amount of the rotation speed setting means every time the operation amount of the operation means is detected by the operation amount detection means. The work vehicle control device according to claim 1. A plurality of the operation means for performing an operation for operating each of the plurality of work devices;
Each of the plurality of operation means includes the first operation detection means,
The power source control means validates the setting operation of the rotation speed setting means when the operation start of two or more of the operation means is detected by a plurality of the first operation detection means, and the rotation speed setting means 3. The work vehicle control device according to claim 1, wherein the number of revolutions of the power source is controlled in accordance with an operation amount of the hydraulic pump so that a discharge flow rate of the hydraulic pump can be variably adjusted.

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