JP4092167B2 - Auxiliary power unit device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention is for temporarily operating an actuator when a hydraulic supply source capable of supplying hydraulic oil to a single-acting hydraulic actuator via a hydraulic pipe fails and the hydraulic actuator becomes inoperable. The present invention relates to a usable auxiliary power unit device.
[0002]
[Prior art]
When a hydraulic actuator for driving a work device mounted on a work vehicle becomes inoperable due to a trouble in a hydraulic system or an electric system of a vehicle-mounted hydraulic supply source, the work or vehicle travel may be hindered. For example, in a cargo handling vehicle equipped with a cargo cradle lifting device, if the hydraulic actuator for raising and lowering the cargo cradle becomes inoperable, the cargo cradle may remain stopped at the lower limit position or during lifting and cannot be stored in the traveling posture. is there.
[0003]
The auxiliary power unit device is effective for temporarily returning the hydraulic actuator that has become inoperable in such a case to an operating position that does not hinder travel. As such an auxiliary power unit, for example, an oil tank, a hydraulic pump that sucks and discharges oil in the oil tank, a supply / discharge oil passage having one end connected to the discharge side of the hydraulic pump, and the supply / discharge oil passage Connecting means capable of detachably connecting the other end of the hydraulic pipe, a return oil passage communicating between the oil tank and the supply / discharge oil passage, and a normally closed electromagnetic on-off valve interposed in the return oil passage, Conventionally, an electric motor for driving a hydraulic pump and a structure including a power supply control means for controlling each power supply to the electric motor and the electromagnetic on-off valve have been known.
[0004]
[Problems to be solved by the invention]
In the energization control unit of the conventional auxiliary power unit device, a power input unit connectable to an external power source, a normally open electromagnetic switching unit that opens and closes between the power input unit and the input side of the electric motor, An operation switch having first and second selection positions that can be arbitrarily input, and when the operation switch is in the first selection position, an input voltage from an external power source is applied to the solenoid of the electromagnetic switching means. By closing the opening / closing means, the electric motor is operated to allow oil supply from the hydraulic pump to the hydraulic piping side. When the switch is in the second selection position, the input voltage is supplied to the solenoid of the electromagnetic opening / closing valve. The oil can be discharged from the hydraulic piping to the oil tank side by opening the on-off valve.
[0005]
However, in the past, for example, either an in-vehicle 12V or 24V battery was used as the external power supply, so that if the power input unit that can be connected to the external power supply is single, that is, dedicated to 12V or 24V, It is necessary to prepare two types of power unit devices, one dedicated to 12V and one dedicated to 24V, which increases the cost and makes storage and management cumbersome.
[0006]
Moreover, in order to solve such a problem, a combined type of 12V and 24V in which both a 12V dedicated power input unit and a 24V dedicated power input unit are provided in a single auxiliary power unit device has been proposed. In this combined type, it is necessary to provide two energization control systems including electromagnetic switching means for 12V and 24V for each 12V and 24V power input unit, and the circuit configuration is complicated accordingly. There is a risk of increasing costs and weight. Furthermore, in the above combination type, since there are two power input sections for 12V and 24V, it is necessary to wire and connect the external power supply to be used correctly, and the connection operation is troublesome and, in the unlikely event, a connection error. If there is, there is a possibility that the device may not move or the wiring of the device may be damaged.
[0007]
The present invention has been made in view of such circumstances, and an object thereof is to provide an auxiliary power unit device that solves the above-described conventional problems with a simple structure.
[0008]
[Means for Solving the Problems]
In order to achieve the above object, the invention of claim 1 is directed to a case where a hydraulic supply source capable of supplying hydraulic oil to a single-acting hydraulic actuator via a hydraulic pipe fails and the hydraulic actuator becomes inoperable. An auxiliary power unit device that can be used to temporarily operate the actuator, and includes an oil tank, a hydraulic pump that sucks and discharges oil in the oil tank, and one end connected to a discharge side of the hydraulic pump. A supply / discharge oil passage, a connecting means capable of detachably connecting the other end of the supply / discharge oil passage to the hydraulic pipe, a return oil passage communicating between the oil tank and the supply / discharge oil passage, and an intermediary between the return oil passage Equipped with a normally closed electromagnetic on-off valve to be mounted, an electric motor for driving a hydraulic pump, and an energization control means for controlling each energization to the electric motor and the electromagnetic on-off valve. an external power supply that A single power input portion connectable Regardless low, the electromagnetic opening and closing means of the normally open type circuit capable of opening and closing the direct for energizing the external power source through the power input unit to the electric motor, optionally First and second selection switches of normally open type that can be input, and a DC voltage input to the power input unit are converted into a constant voltage, and the first and second solenoids of the electromagnetic switching means and the electromagnetic switching valve are respectively Voltage converting means that can output via the second selection switch, and when the first selection switch is input, the constant voltage is applied to the solenoid of the electromagnetic opening / closing means to close the opening / closing means. activates the unconverted electric motor with a DC voltage input to the power input unit to allow the oil supply to the hydraulic pipe side from the hydraulic pump, also at the time of the input operation of the second selection switch, the constant voltage electromagnetic open Is applied to the solenoid valve to allow oil discharged from the hydraulic piping by opening operation of the on-off valve to the oil tank, as the electric motor, assuming the maximum voltage is input from an external power source to the power input unit However, in order not to cause a problem in durability of the motor, the one for the assumed maximum voltage is used .
[0009]
According to the above feature, when a hydraulic supply source capable of supplying hydraulic oil to the hydraulic actuator via a hydraulic pipe fails and the actuator becomes inoperable, the supply / discharge connected to the discharge side of the hydraulic pump of the auxiliary power unit device The oil passage is connected to the hydraulic pipe, and the power input portion of the energization control means is connected to an external power source. In this state, the voltage of the external power source input to the power input unit is converted to a constant voltage by the voltage conversion means. Therefore, when the first selection switch is input, the constant voltage is applied to the solenoid of the electromagnetic switching means. By closing the opening / closing means, the electric motor is operated to allow oil supply from the hydraulic pump to the hydraulic piping side, thereby hydraulically operating the hydraulic actuator that has been inoperable until then in one direction. Can be made. On the other hand, when the second selection switch is operated for input, the constant voltage is applied to the solenoid of the solenoid on / off valve to open the on / off valve, thereby allowing oil to be discharged from the hydraulic piping to the oil tank side. As a result, the hydraulic actuator that has been inoperable can be operated in the other direction by its own weight or the like of the operating device linked to the hydraulic actuator.
[0010]
Thus, since the power supply input section of the energization control means is single and the external power supply only needs to be connected regardless of the voltage level, the connection work is simple and there is a risk of a connection error. There is no. In addition, the DC voltage input from the external power source to this power input unit is converted into a constant voltage by the voltage changing means and output to the electromagnetic opening / closing means and the solenoid of the electromagnetic opening / closing valve. The operating voltage of the solenoid valve can be set to the above-mentioned constant voltage, so that even if the external power supply voltage is not constant, the operation system will not cause malfunction, and the wiring of the device will be damaged. There is no fear of it. In addition, even if the voltage of the external power supply input to the power input section is not constant, there is only one energization control system including the power input section and electromagnetic switching means, so that the circuit configuration is simplified and the cost is reduced. And the weight of the device can be reduced. Further, since the electric motor for the assumed maximum voltage is used, there is no problem in durability of the motor even if the assumed maximum voltage is input from the external power source to the power input section. When a voltage lower than the assumed maximum voltage is input from the power source to the motor, the motor rotates at a normal speed without any trouble although the motor rotation speed is lower than that when the assumed maximum voltage is input. The pump can be driven.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below based on the embodiments of the present invention shown in the accompanying drawings.
[0012]
In the accompanying drawings, FIG. 1 is a side view schematically showing a rear portion of a vehicle with a cargo receiving platform lifting device, and FIG. 2 is an overall circuit diagram showing an example of an auxiliary power unit device.
[0013]
In FIG. 1, a cargo handling vehicle 1 includes a cargo box B on a body frame F, and a load receiving platform elevating device T that is located at the rear of the cargo box B and is used for loading and unloading cargo between the ground and the cargo box B. It is equipped with. The load receiving table elevating device T includes a lifting frame 2 supported by a vehicle body frame F or a packing box B (via a link mechanism in the illustrated example), a horizontal lying position and a vertical position on the lifting frame 2. A load receiving platform 3 supported so as to be able to swing up and down between the standing positions, a lifting hydraulic cylinder A1 for forcibly raising the lifting frame 2, and a hydraulic cylinder for lifting forcibly lifting the loading platform 3 A2.
[0014]
Referring also to FIG. 2, each of the hydraulic cylinders A1, A2 is composed of a single-acting hydraulic cylinder and corresponds to the hydraulic actuator of the present invention. Further, each of the hydraulic oil chambers 4 of the hydraulic cylinders A1 and A2 is parallel to each other via a hydraulic pipe L to a hydraulic supply source PS (see FIG. 2) mounted on the vehicle body frame F and unitized. The hydraulic supply source PS has a built-in control valve that controls supply and discharge of hydraulic oil to and from the hydraulic cylinders A1 and A2.
[0015]
Thus, by supplying hydraulic oil discharged from a hydraulic pump (not shown) of the hydraulic supply source PS to the hydraulic oil chamber 4 of one of the hydraulic cylinders A1 (A2) via the hydraulic pipe L, the lifting frame 2 The (load receiving table 3) can be driven to rise (stand up and turn). Further, by connecting a hydraulic pipe L to an oil tank (not shown) of the hydraulic supply source PS and returning the oil in the hydraulic oil chamber 4 of any hydraulic cylinder A1 (A2) to the oil tank, the lifting frame 2 (load receiving) The table 3) can be lowered (turned down) by its own weight. The configuration and operation of the load receiving table elevating device T described above are well known in the art.
[0016]
By the way, it is difficult for the hydraulic supply source PS to supply hydraulic oil to the hydraulic cylinders A1 and A2 or to discharge hydraulic oil from the hydraulic cylinders A1 and A2 due to failure of the electric system or hydraulic system. It is assumed that the cargo receiving platform 3 remains stopped at the lower limit position or during raising and lowering and cannot be stored in the traveling posture.
[0017]
In such a case, the hydraulic actuators A1 and A2 that have become inoperable are actuated, and the lifting frame 2 and / or the load receiving platform 3 are temporarily moved to an operation position that does not hinder travel (ie, an upper limit position and / or a standing position). The auxiliary power unit device U according to the present invention is used for the return operation. Next, a specific configuration of the auxiliary power unit apparatus U will be described with reference to FIG.
[0018]
The auxiliary power unit device U includes an oil tank T, a hydraulic pump P that sucks and discharges oil in the oil tank T, a supply / discharge oil passage Lu having one end connected to the discharge side of the hydraulic pump P, and the hydraulic pump P. A return oil path Ld that bypasses and communicates between the oil tank T and the supply / discharge oil path Lu, a normally closed electromagnetic on-off valve V that is interposed in the return oil path Ld, and an electric motor that drives the hydraulic pump P M and a control circuit C as energization control means for controlling energization of the electric motor M and the electromagnetic on-off valve V are provided in a single unit housing Ua formed in a portable box shape. Is done.
[0019]
The other end side of the supply / discharge oil passage Lu is constituted by a flexible hydraulic conduit Lu ′ extending from the unit housing Ua, and the extending end portion is detachably connected to the hydraulic pipe L. A joint J is provided as a connecting means capable of communicating between the hydraulic pipe L and the supply / discharge oil passage Lu. Further, the electromagnetic on-off valve V has a check valve function that shuts off only one direction from the supply / discharge oil passage Lu to the oil tank T side in the closed position. Further, a check valve 11 is interposed upstream of the connection portion of the supply / discharge oil passage Lu with the return oil passage Ld, and further, an upstream pressure gauge 12 can be connected upstream of the check valve 11. The monitor circuit 13 is branched.
[0020]
The control circuit C directly opens and closes a single power input part I that can be connected to an external power source, for example, an in-vehicle battery E, and a circuit for energizing the electric motor M from the battery E via the power input part I. Contactor X as a normally open type electromagnetic opening / closing means, normally open type first and second selection switches S1 and S2 which can be arbitrarily input, and the DC voltage inputted to the power input unit I is constant. A voltage conversion means RE that converts the voltage into voltage and outputs the voltage to the contactor X and the solenoids Xs and Vs of the electromagnetic on-off valve V via the first and second selection switches S1 and S2, respectively .
[0021]
In the illustrated example, the voltage converting means includes an input terminal, a ground terminal, and an output terminal, and a DC voltage input to the input terminal can be converted to a constant voltage (12 V in the illustrated example) and output to the output terminal side. A well-known three-terminal regulator is used. The first and second selection switches S1 and S2 may be provided on an operation panel S attached to the unit housing Ua, or a remote controller (not shown) connected from the unit housing Ua via a connection cord. As the electromagnetic on-off valve V and the contactor X, those having an operating voltage of 12 V are used corresponding to the output voltage of the voltage conversion means RE in the illustrated example. Further, the electric motor M is used for 24V so that no problem occurs in durability of the motor M even if a voltage of 24V, which is the assumed maximum voltage, is input from the external power source E to the electric motor M via the contactor X. However, if a voltage of 12V is input to the motor M from the external power source E, the motor M has a motor speed that is greatly reduced (substantially halved) compared to a case where a voltage of 24V is input. However, the hydraulic pump P can be driven by rotating without trouble.
[0022]
Thus, the first selection switch S1 operates the electric motor M by applying the constant voltage to the solenoid Xs of the contactor X to close the opening / closing means X during the input operation to the hydraulic pump P. Enables oil supply to the hydraulic piping L side. Further, the second selection switch S2 applies the constant voltage to the solenoid Vs of the electromagnetic on-off valve V during the input operation thereof, and opens the on-off valve V to open the hydraulic tank L to the oil tank T side. The oil can be discharged.
[0023]
Next, the operation of the embodiment will be described. When the hydraulic supply source PS is normal, the hydraulic oil discharged from a hydraulic pump (not shown) of the hydraulic supply source PS is supplied to the hydraulic oil chamber 4 of one of the hydraulic cylinders A1 and A2 via the hydraulic pipe L. Thus, the elevating frame 2 or the load receiving platform 3 can be driven upright or turned upright, and a hydraulic pipe L is communicated with an oil tank (not shown) of the hydraulic supply source PS so that any one of the hydraulic cylinders A1, A2 is connected. By returning the oil in the hydraulic oil chamber 4 to the oil tank, the elevating frame 2 or the load receiving platform 3 can be lowered or turned over by its own weight.
[0024]
Further, when it becomes difficult to supply hydraulic oil to the hydraulic cylinders A1 and A2 or to discharge hydraulic oil from the hydraulic cylinders A1 and A2 due to a failure of the electrical system or hydraulic system of the hydraulic supply source PS, the lifting frame 2 and / or Alternatively, the load receiving platform 3 may remain stopped at the lower limit position or while being lifted and cannot be stored in the traveling posture.
[0025]
In such an emergency, the auxiliary power unit device U is prepared, and the hydraulic oil chamber Lu of the raising / lowering hydraulic cylinder A1 or the raising / lowering hydraulic cylinder A2 is connected to the supply / discharge oil passage Lu connected to the discharge side of the hydraulic pump P via the joint J. 4 is connected to a hydraulic pipe L connected to 4 and the power input unit I is connected to an external power source, for example, an in-vehicle 12V or 24V battery E. With this connection, the voltage of the battery E input to the power input unit I is converted to a constant voltage (ie, 12 V) by the voltage conversion means RE. Therefore, when the first selection switch S1 is input, the constant voltage is converted into the contactor. Applied to the X solenoid Xs, the contactor X is closed. Thereby, in order to operate the electric motor M to enable oil supply from the hydraulic pump P of the auxiliary power unit U to the hydraulic pipe L side, the hydraulic cylinder A1 or A2 that has been inoperable until then is hydraulically operated, Thereby, the raising / lowering frame 2 or the load receiving stand 3 can be driven upright or turned upright to return to the respective traveling postures, and the vehicle 1 can travel.
[0026]
On the other hand, when the second selection switch S2 is input, the constant voltage (that is, 12V) is applied to the solenoid Vs of the electromagnetic on-off valve V to open the on-off valve V. As a result, oil can be discharged from the hydraulic pipe L connected to the hydraulic oil chamber 4 of the lifting hydraulic cylinder A1 or the hydraulic cylinder A2 for raising and lowering to the oil tank T side of the auxiliary power unit U. The hydraulic cylinder A1 or A2 can be lowered or turned down by its own weight, such as the load receiving table 3 linked to the hydraulic cylinder A1 or A2, so that the cargo being unloaded can be returned to the ground.
[0027]
Thus, the power input unit I in the auxiliary power unit U is single, and the vehicle-mounted battery E as an external power source is connected to the auxiliary power unit U regardless of the level of the voltage (that is, regardless of whether the battery is 12V or 24V). Since it only has to be connected, the connection work is simple and there is no fear of a connection error.
[0028]
Further, since the DC voltage input from the battery E to the power input unit I is converted into a constant voltage (12V) by the voltage changing means RE and output to the contactor X and the solenoids Xs and Vs of the electromagnetic on-off valve V, these contactors are used. Each operating voltage of X and the electromagnetic on-off valve V can be set to the above-mentioned constant voltage (12V), so that even if the voltage of the battery E input to the power input unit I is 12V or 24V, the operation voltage There is no possibility that the system devices X and V will malfunction, and there is no possibility that the wiring portion of the apparatus will be damaged.
[0029]
Even if the voltage of the battery E input to the power input unit I is 12V or 24V, there are only a few energization control systems including the power input unit I, the contactor X, the first and second selection switches S1, S2, etc. Since only one system (that is, a 12V compatible system) is required, the overall circuit configuration of the control circuit C is simplified, and cost saving and weight reduction of the apparatus are achieved.
[0030]
As mentioned above, although one Example of this invention was described, this invention is not limited to the Example, A various Example is possible within the scope of the present invention.
[0031]
For example, in the above-described embodiment, the auxiliary power unit device U of the present invention is used when hydraulic actuators mounted on a work vehicle (lifting hydraulic cylinder A1 and lifting hydraulic cylinder A2 of the load receiving table lifting device T) cannot be operated. Although the case where the hydraulic actuators A1 and A2 are temporarily urgently operated has been described, in the present invention, the auxiliary power unit device U is applied not only to the hydraulic actuator of the load receiving table elevating device T but also to the hydraulic actuators of other work vehicles. May be. Further, it can be used not only for emergency operation as in the above-described embodiment, but also as a small hydraulic power source unit when operating or adjusting a general hydraulic device.
[0032]
Moreover, in the said Example, the vehicle-mounted 12V or 24V battery E was used as an external power supply which supplies electric power to the auxiliary | assistant power unit apparatus U, However, Various batteries (including the battery which is not vehicle-mounted) of other voltage values are used. Is also possible.
[0033]
【The invention's effect】
As described above, according to the present invention, the power input unit in the auxiliary power unit device is single, and the external power source can be connected to the auxiliary power unit device regardless of the voltage level. Since it is simple and there is no fear of connection mistakes, workability is improved. In addition, the DC voltage input from the external power source to this power input unit is converted into a constant voltage by the voltage changing means and output to the electromagnetic opening / closing means and the solenoid of the electromagnetic opening / closing valve. The operating voltage of the solenoid valve can be set to the above-mentioned constant voltage, so that even if the voltage of the external power supply is not constant, the operation system will not cause malfunction, and the wiring section of the device, etc. There is no risk of damage. In addition, even if the voltage of the external power supply input to the power input section is not constant, there is only one energization control system including the power input section and electromagnetic switching means, so that the circuit configuration is simplified and the cost is reduced. And can greatly contribute to weight reduction of the device. Furthermore, since an electric motor for the assumed maximum voltage is used, there is no problem in durability of the motor even if the assumed maximum voltage is input from the external power supply to the power input section. When a voltage lower than the assumed maximum voltage is input to the motor, the motor rotates at a satisfactory speed, although the motor rotation speed is lower than that when the assumed maximum voltage is input. Can be driven.
[Brief description of the drawings]
FIG. 1 is a schematic side view showing a rear portion of a vehicle with a load receiving platform lifting apparatus according to an embodiment of the present invention. FIG. 2 is an overall circuit diagram showing an example of an auxiliary power unit device.
A1 ・ ・ Hydraulic hydraulic cylinder (hydraulic actuator)
A2 ・ ・ Hydraulic hydraulic cylinder (hydraulic actuator)
C: Control circuit (energization control means)
E ... Battery (External power supply)
I ... Power input part J ... Joint (connection means)
L ... Hydraulic piping Ld ... Return oil passage Lu ... Supply / discharge oil passage M ... Electric motor P ... Hydraulic pump PS ... Hydraulic supply source RE ... 3 terminal regulator (voltage conversion means)
S1, S2,... First and second selection switch T ... Oil tank U ... Auxiliary power unit device Ua ... Unit housing V ... Solenoid open / close valve Vs ... Solenoid X ... Contactor (electromagnetic open / close) means)
Xs solenoid

Claims (1)

When a hydraulic supply source (PS) that can supply hydraulic oil to the single-acting hydraulic actuator (A1, A2) via the hydraulic pipe (L) fails and the hydraulic actuator (A1, A2) becomes inoperable And an auxiliary power unit device that can be used to temporarily actuate the actuators (A1, A2),
An oil tank (T), a hydraulic pump (P) for sucking and discharging the oil in the oil tank (T), a supply / discharge oil passage (Lu) having one end connected to the discharge side of the hydraulic pump (P), Returning oil that communicates between the connecting means (J) that can removably connect the other end of the supply / discharge oil passage (Lu) to the hydraulic pipe (L), and the oil tank (T) and the supply / discharge oil passage (Lu). A path (Ld), a normally closed electromagnetic on-off valve (V) interposed in the return oil path (Ld), an electric motor (M) for driving a hydraulic pump (P), and an electric motor (M ) And energization control means (C) for controlling each energization to the electromagnetic on-off valve (V),
The energization control means (C) is electrically driven from the external power source (E) through the single power source input unit (I) to which the external power source (E) can be connected regardless of its height and the power source input unit (I). A normally open type electromagnetic opening / closing means (X) capable of directly opening and closing a circuit for energizing the motor (M), and a normally open type first and second selection switches (S1, S2) which can be arbitrarily input. The DC voltage input to the power input unit (I) is converted to a constant voltage, and the first and second solenoids (Xs, Vs) of the electromagnetic on / off means (X) and the electromagnetic on / off valve (V) are first and second respectively. and a voltage converting means can output via the second selection switch (S1, S2) (RE) ,
When an input operation of the first selection switch (S1), by operating close said opening and closing means (X) by applying the constant voltage to the solenoid (Xs) of the electromagnetic switching device (X), the power input unit ( The electric motor (M) is operated by the unconverted DC voltage input to I) to enable oil supply from the hydraulic pump (P) to the hydraulic pipe (L), and the second selection switch (S2) At the time of input operation, the constant voltage is applied to the solenoid (Vs) of the electromagnetic on-off valve (V) to open the on-off valve (V) to open the hydraulic pipe (L) to the oil tank (T) side. Enables oil discharge ,
The electric motor (M) is for the assumed maximum voltage so that no problem occurs in the durability of the motor (M) even if the assumed maximum voltage is input from the external power source (E) to the power input part (I). characterized in that is used as the auxiliary power unit system.

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