JP4107998B2 - Motor control device for work vehicle - Google Patents

Description

【００１７】
このような構成によると、作業員が、操作装置６からポンプ駆動モータ７を停止する（オフする）操作をしたにも関わらず、操作コンタクタ１３の異常（例えば、接点１３ｂの固着）によりポンプ駆動モータ７の駆動が続いたとしても、固着検出装置１７により遮断装置１６を介して電源コンタクタ１２の接点１２ｂが開放されて電源１１からの電源供給が自動的に遮断される。そのため、ポンプ駆動モータ７により駆動される油圧ポンプ８が停止することにより、例えばマスト４の伸縮作動（作業台５の昇降作動）が停止して作業員の意図しない動作をすることがないため、安全性を向上させることができる。このとき、ポンプ駆動モータ７に供給される電源１１の開閉に電源コンタクタ１２及び操作コンタクタ１３を用いることにより、電気信号による制御としてモータ制御装置１０を構成することができるので、装置構成を簡単にすることができるとともに、回路の開閉動作を速くすることができるので、固着検出装置１７における異常検出時の作業装置（マスト４の伸縮作動）の停止が速くなり、安全性をより向上させることができる。
【００１８】
なお、電源コンタクタ１２と操作コンタクタ１３の電源１１およびポンプ駆動モータ７に対する接続の順序は、逆にして構成することもできる。また、以上の説明では、ポンプ駆動モータ７が油圧アクチュエータ（伸縮シリンダ９）に作動油を供給する油圧ポンプ８を駆動する場合において、このポンプ駆動モータ７を制御するためのモータ制御装置１０について説明したが、この高所作業車１を走行させるための電動モータ（上述のクローラ装置３，３を駆動するための電動モータ）に対しても同様にモータ制御装置１０を適用することができる。
【００１９】
【発明の効果】
以上説明したように、本発明に係る作業車のモータ制御装置によれば、油圧アクチュエータに作動油を供給するための油圧ポンプを駆動する電動モータとこの電動モータを駆動する電源との回路上に、第１のスイッチ（操作コンタクタ）と第２のスイッチ（電源コンタクタ）とを直列に接続し、操作装置の操作に対応して開閉する第１のスイッチの接点が溶融して固着した場合に固着検出装置で検出するように構成されている。さらに、この固着検出装置で固着が検出されて出力された検出信号により遮断装置を介して第２のスイッチをオフして電源からの電動モータへの電力供給を遮断するように構成している。このため、第１のスイッチの固着が発生しても、油圧アクチュエータにより駆動される作業装置が停止して、作業員の予期せぬ作動をしないため、安全性を向上させることができる。
【図面の簡単な説明】
【図１】本発明に係る作業車のモータ制御装置を示すブロック図である。
【図２】本発明が適用される作業車の斜視図である。
【符号の説明】
１ 高所作業車（作業車）
２ 車体
４ マスト（作業装置）
５ 作業台（作業装置）
６ 操作装置
７ ポンプ駆動モータ（電動モータ）
８ 油圧ポンプ
９ 伸縮シリンダ（油圧アクチュエータ）
１０ モータ制御装置
１１ 電源
１２ 電源コンタクタ（第２のスイッチ）
１３ 操作コンタクタ（第１のスイッチ）
１６ 遮断装置
１７ 固着検出装置[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a motor control device for a work vehicle that controls an electric motor for driving a hydraulic pump that supplies hydraulic oil to a hydraulic actuator that drives the work device in a work vehicle having a work device on a vehicle body.
[0002]
[Prior art]
In an aerial work vehicle, which is a work vehicle configured such that a worker gets on a work device disposed on a vehicle body and moves to a desired high place to perform work, an actuator for raising and lowering the work device is hydraulic. The hydraulic pump that supplies hydraulic oil to the actuator is driven by an electric motor. At this time, if the contact of the contactor for controlling the operation of the electric motor is melted and fixed, the electric motor is always supplied with power, and the electric motor cannot be stopped even if the worker stops the operation. The operation of the actuator continues and the work device operates unexpectedly. For this reason, such work vehicles are generally provided with an emergency stop switch for urgently stopping the operation of the work device in order to ensure the safety of the passenger (worker) (for example, Patent Document 1). reference).
[0003]
[Patent Document 1]
Japanese Patent Application Laid-Open No. 2002-46997 (page 3, FIG. 2)
[0004]
[Problems to be solved by the invention]
However, if the operation of the emergency stop switch is delayed, there is a problem that an unexpected operating range of the working device becomes large and safety is lowered.
[0005]
The present invention has been made in view of such a problem, and the first switch is fixed when the electric motor for driving the hydraulic pump is driven even though the operation signal from the operation device is OFF. An object of the present invention is to provide a motor control device for a work vehicle configured to detect the above.
[0006]
[Means for Solving the Problems]
In order to solve the above-described problems, a motor control device for a work vehicle according to the present invention includes a work device (for example, the mast 4 and work table 5 in the embodiment) disposed on a vehicle body, and an operation device that operates the work device. A hydraulic actuator that operates the working device (for example, the telescopic cylinder 9 in the embodiment), a hydraulic pump that supplies hydraulic oil to the hydraulic actuator, and an electric motor that drives the hydraulic pump (for example, the pump drive in the embodiment) It controls the operation of the electric motor in a work vehicle having a motor 7) and a power source for driving the electric motor (for example, an aerial work vehicle 1 in the embodiment). The first switch that is turned on / off (for example, the operation contactor 13 in the embodiment) and the power switch of the work vehicle when the main power is turned on. The second switch (for example, the power contactor 12 in the embodiment) is disposed in series with the wiring connecting the power source and the electric motor, the operation device is off, and the electric motor is operating. Sometimes, it is configured to include a sticking detection device that detects sticking of the first switch and outputs a detection signal (for example, the sticking detection signal S _E in the embodiment).
[0007]
According to such a configuration, the sticking detection device can detect sticking of the first switch from the state of the operating device and the electric motor. In addition, it is preferable to have a shut-off device that turns off the second switch by the detection signal when the first switch is detected by the sticking detection device and a detection signal is output. According to such a configuration, since the operation of the electric motor can be stopped by turning off the second switch by the shut-off device when the detection signal is output, malfunction of the work device can be prevented. . Therefore, even if the worker does not operate the emergency stop switch, the operation of the work device is stopped by the work vehicle motor control device according to the present invention, so that the safety of the work vehicle can be improved.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. First, before describing a motor control device for a work vehicle according to the present invention, a crawler type indoor work vehicle will be described as an example of a work vehicle to which the motor control device is attached. As shown in FIG. 2, the aerial work vehicle 1 includes crawler devices 3 and 3 on both left and right sides of the vehicle body 2, and is configured to be able to travel by driving the crawler devices 3 and 3 with an electric motor (not shown). . The aerial work vehicle 1 has a power supply (storage battery or the like) inside, and an electric motor for driving the crawler devices 3 and 3 and a pump drive motor described later are driven by this power supply. A mast 4 extending vertically upward with respect to the vehicle body 2 is disposed at the upper front side of the vehicle body 2. The mast 4 has a plurality of mast members (only the base end mast 4a and the tip mast 4b shown in FIG. 2 are shown in a nested manner) and can be expanded and contracted vertically, and an expansion cylinder (see FIG. 2 (not shown in FIG. 2) so that it can be expanded and contracted.
[0009]
A work table 5 is attached to a lower side surface (rear side surface) of the tip mast 4b so as to be positioned above the vehicle body 2, and the floor of the work table 5 extends substantially horizontally. The mast 4 and the work table 5 constitute a work device that moves a worker on the work table 5 to a desired height. An operation device 6 for operating the crawler device 3 to drive the aerial work vehicle 1 and moving the mast 4 up and down to raise and lower the work table 5 is disposed above the tip mast 4b. The operation device 6 is connected to a motor control device to be described later. A key switch is provided on the top of the tip mast 4b. By operating this key switch, the main power source of the aerial work vehicle 1 is turned on so that power is supplied to the electric motor and the like. It is configured. For this reason, when the main power supply is turned on, the aerial work vehicle 1 can be run, the work device can be operated, and the like.
[0010]
A telescopic cylinder for expanding and contracting the mast 4 is hydraulically operated. As shown in FIG. 1, a hydraulic pump 8 for supplying hydraulic oil to the telescopic cylinder 9 and an electric motor for driving the hydraulic pump 8 (Hereinafter referred to as “pump drive motor 7”) is disposed in the vehicle body 2 (not shown in FIG. 2). In the following description, the motor control device 10 according to the present invention for controlling the pump drive motor 7 will be described. In FIG. 1, the electric circuit is indicated by a solid line, and the hydraulic circuit is indicated by a broken line. In FIG. 2, only the operation device 6 related to the expansion / contraction operation of the mast 4 (extraction / contraction operation of the expansion / contraction cylinder 9) is illustrated.
[0011]
The pump drive motor 7 is configured to be driven by a power supply 11 mounted on the vehicle body 2, and contacts 12 b and 13 b of the power contactor 12 and the operation contactor 13 are connected in series on the circuit of the power supply 11 and the pump drive motor 7. Is connected. The contactor means that when a voltage (contact opening / closing signal) is applied to the opening / closing mechanism parts 12a, 13a composed of an electromagnet or the like, the contacts 12b, 13b are opened and closed by a magnetic force generated by the voltage, and the contacts 12a, 13a The circuit connected to is electrically connected / disconnected. In the power contactor 12 and the operation contactor 13, protective rectifiers 14 and 15 are connected in parallel to the switching mechanism portions 12a and 13a, respectively.
[0012]
A shutoff device 16 is connected to the opening / closing mechanism 12a of the power contactor 12, and the contact point 12b of the power contactor 12 is configured to be open when the main power of the aerial work vehicle 1 is not turned on. ing. When a key switch provided on the vehicle body 2 (tip mast 4b) is turned on and the main power of the aerial work vehicle 1 is turned on, a power open / close signal S _S (closed) is sent to the shut-off device 16 to The contact 12b of the contactor 12 is closed. The aerial work vehicle 1 is provided with an emergency stop switch (not shown) for stopping the expansion and contraction operation of the mast 4 in an emergency, and when the emergency stop switch is turned on, S _S (open) is sent to the shut-off device 16, which shuts off the power supply from the power source 11 to the pump drive motor 7 by opening the contact 12 b of the power contactor 12.
[0013]
On the other hand, the operating device 6 is connected to the opening / closing mechanism portion 13a of the operating contactor 13, and when the operating device 6 is turned on in response to the operation of the operating device 6 by a worker on the work table 5, the contact point 13b is closed to supply power to the pump drive motor 7, and when the operating device 6 is turned off, the contact 13b is opened to stop supplying power to the pump drive motor 7. . Therefore, when the contact 12b of the power contactor 12 is in the closed state, the contact 13b of the operation contactor 13 is opened and closed by the operator turning on / off the operation device 6 to control the driving / stopping of the pump drive motor 7. It is configured.
[0014]
For this reason, since the operation contactor 13 is used to turn on / off the power supplied to the pump drive motor 7 in the energized state, for example, when the work table 5 is loaded, the power is turned on / off. If the operation is performed, a large current may flow through the contact 13b, the contact 13b may melt and be fixed, and the pump drive motor 7 may be energized at all times. Therefore, the motor control device 10 according to the present invention, have a fixed detector 17 for detecting the sticking of contacts 13b of the operation contactor 13 and a drive signal S _R of the operation signal S _C and the pump driving motor 7 from the operation unit 6 When the sticking is detected, the sticking detection device 17 outputs the sticking detection signal S _E to the blocking device 16 to open the contact 12b of the power contactor 12. . The driving signal S _R of the pump drive motor 7 is a signal power is detected the state of being supplied to the pump drive motor 7.
[0015]
In anchoring detector 17, the correspondence between the fixed detection signal S _E to the operation signal S _C and a motor drive signal S _R, a logic relationship shown in Table 1 below. As shown in Table 1, when the pump drive motor 7 is driven (when the drive signal S _R is on) even though the operation signal S _C from the operation device 6 is off, the sticking detection is performed. and it is configured to output a signal S _E as an abnormal detection state. When the sticking detection signal S _E is output as an abnormality detection signal, the shutoff device 16 opens the contact 12b of the power contactor 12 and shuts off the supply of the power supply 11 to the pump drive motor 7.
[0016]
[Table 1]

[0017]
According to such a configuration, the operator drives the pump due to an abnormality in the operation contactor 13 (for example, the contact 13b is fixed) even though the operator performs an operation of stopping (turning off) the pump drive motor 7 from the operation device 6. Even if the motor 7 continues to be driven, the contact detection device 17 opens the contact 12b of the power contactor 12 via the shut-off device 16 and the power supply from the power source 11 is automatically shut off. Therefore, when the hydraulic pump 8 driven by the pump drive motor 7 is stopped, for example, the expansion / contraction operation of the mast 4 (the raising / lowering operation of the work table 5) stops and the operation not intended by the worker does not occur. Safety can be improved. At this time, by using the power contactor 12 and the operation contactor 13 to open and close the power supply 11 supplied to the pump drive motor 7, the motor control device 10 can be configured as control by an electric signal, so that the device configuration can be simplified. In addition, since the opening / closing operation of the circuit can be speeded up, the working device (the expansion and contraction operation of the mast 4) at the time of abnormality detection in the sticking detection device 17 is quickly stopped, and the safety can be further improved. it can.
[0018]
Note that the order of connection of the power contactor 12 and the operation contactor 13 to the power supply 11 and the pump drive motor 7 can be reversed. In the above description, the motor control device 10 for controlling the pump drive motor 7 when the pump drive motor 7 drives the hydraulic pump 8 that supplies hydraulic oil to the hydraulic actuator (the telescopic cylinder 9) is described. However, the motor control device 10 can be similarly applied to the electric motor (the electric motor for driving the above-described crawler devices 3 and 3) for running the aerial work vehicle 1.
[0019]
【The invention's effect】
As described above, according to the motor controller for a work vehicle according to the present invention, an electric motor that drives a hydraulic pump for supplying hydraulic oil to a hydraulic actuator and a power source that drives the electric motor are arranged on a circuit. When the first switch (operation contactor) and the second switch (power contactor) are connected in series and the contact of the first switch that opens and closes in response to the operation of the operation device is fused and fixed It is comprised so that it may detect with a detection apparatus. Further, the second detection switch is turned off by the detection signal output when the sticking detection device detects the sticking, and the power supply from the power source to the electric motor is shut off. For this reason, even if the first switch is stuck, the working device driven by the hydraulic actuator stops and does not operate unexpectedly by the worker, so that safety can be improved.
[Brief description of the drawings]
FIG. 1 is a block diagram showing a motor controller for a work vehicle according to the present invention.
FIG. 2 is a perspective view of a work vehicle to which the present invention is applied.
[Explanation of symbols]
1 High-altitude work vehicle (work vehicle)
2 Car body 4 Mast (work equipment)
5 Work table (work equipment)
6 Operation device 7 Pump drive motor (electric motor)
8 Hydraulic pump 9 Telescopic cylinder (hydraulic actuator)
10 motor controller 11 power supply 12 power contactor (second switch)
13 Operation contactor (first switch)
16 Blocking device 17 Sticking detection device

Claims (2)

A working device disposed in a vehicle body, an operating device for operating the working device, a hydraulic actuator for operating the working device, a hydraulic pump for supplying hydraulic oil to the hydraulic actuator, and for driving the hydraulic pump A work vehicle motor control device for controlling the operation of the electric motor in a work vehicle having an electric motor and a power source for driving the electric motor,
A first switch that is turned on / off in response to on / off of the operating device; and a second switch that is turned on when a main power of the work vehicle is turned on; In series with the wiring to connect,
A motor control for a work vehicle, comprising: a sticking detection device that detects sticking of the first switch and outputs a detection signal when the operating device is off and the electric motor is operating. apparatus. The work vehicle motor control device according to claim 1, further comprising: a shut-off device that turns off the second switch when the detection signal is output.

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