JP2003049781A - Hydraulic device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a hydraulic device capable of reducing shock on starting. SOLUTION: The opening of a control valve 52 is changed via an interlocking mechanism 62 in response to the turning angle of an operation lever 4 in an ON area A- ON so that a working fluid discharged from a hydraulic pump 2 must not be immediately supplied to an external actuator even when an electric motor 1 is started.

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid having an electric motor, a hydraulic pump, a tank, etc., which can supply a working fluid to an external actuator by operating the electric motor. Pressure device. 2. Description of the Related Art Conventionally, a hydraulic device of this type is operated by turning an electric motor on and off by operating an operating lever to rotate a hydraulic pump, and a working fluid discharged from the hydraulic pump is supplied to an external device such as a cylinder. It is supplied to the actuator. However, when the electric motor is started, the hydraulic fluid may be discharged at once from the hydraulic pump and flow into the cylinder or the like to cause a shock. In response to such a problem, for example, it is conceivable to gradually control the rotation speed of the electric motor according to the operation amount of the operation lever in the ON direction by, for example, driving the electric motor with an inverter. Such an electric control method is not very preferable in consideration of the severe environment in which the device is provided, cost, operation reliability when controlling a large current flowing through the electric motor, and the like. In order to solve the above problem with a simple and reliable structure, the present invention mechanically interlocks a control valve for supplying a hydraulic fluid to an external actuator with an operation lever for operating the electric motor, and At the time of operation, the fluid discharged from the hydraulic pump flows into the tank, and the flow rate of the fluid supplied to the actuator increases in accordance with the operation amount of the operation lever therefrom. That is, a hydraulic device according to the present invention comprises an electric motor that is turned on and off, a hydraulic pump that is driven by the electric motor to discharge fluid from a discharge port, a tank, An operation lever that turns the motor when rotated to a predetermined ON region and stops the motor when turned to an OFF region set adjacent to the ON region; a discharge port of the hydraulic pump; A communication path communicating with the tank, a control valve provided on the communication path, which moves forward and backward in a direction orthogonal to the rotation axis of the operation lever, and controls a flow rate thereof; and An interlocking mechanism for interlocking the turning operation with the forward / backward movement of the control valve. With such a configuration, the opening degree of the control valve is changed in accordance with the rotation angle of the operation lever in the ON region, so that even when the electric motor is started, the working fluid discharged from the hydraulic pump is immediately supplied. Can be prevented from being supplied to the external actuator, so that a shock or the like caused by the supply of the working fluid to the external actuator at once at the time of starting the electric motor can be suppressed. Further, since the operating lever for operating the electric motor is also used for operating the control valve by using the interlocking mechanism, the number of parts can be reduced, and the cost and reliability are excellent. It can be. In addition, since the control valve moves back and forth in a direction different from the rotation axis of the operation lever, the degree of freedom of the arrangement position of the control valve is increased, and the apparatus can be made compact. An embodiment of the present invention will be described below. FIGS. 1 and 2 are overall views showing a hydraulic device 100 according to this embodiment. This hydraulic device 10
Numeral 0 is used for an industrial vehicle such as a tailgate vehicle, and connects the electric motor 1 and the hydraulic pump 2 (not shown in the figure) via an adapter plate 7. Tank 3, various valves 50, 51, 5
2. A switch SW for the electric motor 1 and an operation lever 4 for turning the switch SW on and off are mounted in addition to hydraulic pressure-related members such as the output port P2 to form an integral structure. As shown in FIGS. 3 and 4, the discharge port P1 of the hydraulic pump 2 is connected to an external actuator (not shown) via a main fluid path R0 provided in the adapter plate 7. Connected to the output port P2. A main check valve 50 is provided on the main fluid path R0 to prevent fluid from flowing back from the external actuator to the pump discharge port P1. In the adapter plate 7, two branch fluid paths (a first branch path R1 and a second branch path R as a communication path) from the main fluid path R0 to the tank 3 are provided.
2) are provided in parallel, and each of these branch paths R
1, a first control valve 51 and a second control valve 5 on R2, respectively.
2 are arranged. The “communication route” according to claim 1
Is in the second branch path R2, and the “control valve” is in the second branch path R2.
It corresponds to the control valve 52. The first branch path R1 branches from the main fluid path R0 downstream of the main check valve 50 and communicates with a tank port P3 provided in the adapter plate 7. In addition, the first control valve 5 provided on the route R1
Reference numeral 1 denotes a check valve type in which a ball 511 is pressed against a seat 513 by a spring 512 to urge the ball 511 to prevent the flow of fluid toward the tank port P3. The second branch path R2 branches from the main fluid path R0 upstream of the main check valve 50 and communicates with the tank port P3. Also, the route R
The second control valve 52 provided on the second valve 2 is also a check valve type in which a poppet 521 having a conical surface is pressed against a seat 523 by a spring 522 so as to urge the poppet 521 to block the flow of fluid toward the tank port P3. . On the other hand, the operation lever 4 is
And a rotating shaft 42 which is connected to the lever body 41 so as to be orthogonal to the lever body 41. By fitting the rotating shaft 42 into a bearing hole 71 provided in the adapter plate 7, Is mounted so as to be rotatable. When the operation lever 4 is rotated into a predetermined ON area A_ON shown in FIG.
When the W is turned on, the motor 1 is operated, and when the motor 1 is turned to the off area A_OF side adjacent to the on area A_ON, the switch SW is turned off and the motor 1 is stopped. In the present embodiment, however, the turning operation of the operation lever 4 is further converted into a first interlocking mechanism 61 for converting the opening and closing operation of the first control valve 51 and an opening and closing operation of the second control valve 52. And a second interlocking mechanism 62 for conversion. It should be noted that the “interlocking mechanism” according to claim 1 is the second interlocking mechanism 6.
Equivalent to 2. More specifically, the first interlocking mechanism 61 further aligns the axis L1 from the tip of the rotary shaft 42 with the screw rod 611 integrally protruding therefrom, and further aligns the axis L1 from the screw rod 611 with the axis L1. A cylindrical pushing member 612 that is integrally extended.
The screw rod 611 is screwed into a female screw hole 613 provided in the adapter plate 7. Then, a neutral position A_M which is a boundary portion between the off-region A_OF and the on-region A_ON.
When the operation lever 4 is positioned at the position, the tip of the pushing member 612 is separated from the ball 511 of the first control valve 51 or comes into contact with the ball 511 to such an extent that the ball 511 does not separate from the seat 513. It is set so that one control valve 51 can be closed. On the other hand, by turning the operation lever 4 from the neutral position A_M toward the off region A_OF, the screw rod 611 is screwed into the inside, and the ball 511 is moved by the pushing member 612 in a direction to separate the ball 511 from the seat 513. One control valve 51 is set to be opened. The second interlocking mechanism 62 includes a cam member 621 integrally provided between the screw rod 611 and the pushing member 612.
And a columnar driven member 622 integrally protruding from the poppet 521 of the second control valve 52 so that the distal end abuts on the cam member 621. The cam member 621 has an elliptical cross section and a cam surface 62a.
Is formed. On the other hand, the driven member 62
2 moves forward and backward by sliding its tip against the cam surface 62a.
The screw rod 611 or the pushing member 612 is configured to be orthogonal to the direction of the axis L1. Then, the operating lever 4 is moved to the neutral position A_
M, the portion of the cam surface 62a corresponding to the major axis of the ellipse faces the driven member 622 side.
2 is pushed against the spring force to separate the poppet 521 from the sheet 523. Further, by turning the operation lever 4 from the neutral position A_M toward the ON region A_ON, the portion corresponding to the elliptical minor diameter portion of the cam surface 62a faces the driven member 622 side, and at the rotation end, the driven member 622 The second control valve 52 is set to be closed such that the tip of the second control valve 52 is separated from the cam surface 62a or is brought into contact with the poppet 521 so as not to be separated from the seat 523. Next, the present hydraulic apparatus 100 constructed as described above
The operation of will be described. When the operation lever 4 is in the neutral position A_M, the portion corresponding to the long diameter portion of the cam surface 62a faces the driven member 622 side, so that the poppet 521 of the second control valve 52 is separated from the seat 522. It becomes fully open,
This second branch route R2 is brought into a communicating state. When the operation lever 4 is turned to the ON area A_ON side beyond the neutral position A_M, the switch SW is turned on, the electric motor 1 is operated, and the hydraulic pump 2 is rotated. In the immediate area, the second control valve 52 is almost fully open, so the fluid discharged from the hydraulic pump 2 returns to the tank 3 via the second branch path R2 and the tank 3 port. Then, the operation lever 4 is further moved to the ON area A_
As the motor 1 is turned to the ON side, the portion corresponding to the short diameter portion of the cam surface 62a gradually faces the driven member 622 side according to the lever rotation angle while the electric motor 1 is in the operating state.
The poppet 521 of the second control valve 52 gradually becomes the seat 522.
And its opening is reduced. When the pressure loss of the working fluid flowing through the second control valve 52 becomes larger than the output port pressure caused by the load from the external actuator (for example, a cylinder), the working fluid discharged from the hydraulic pump 2 is discharged. , The ball of the main check valve 50 is pushed up and supplied to the external actuator from the output port P2. When the operating lever 4 is further turned to the turning end of the ON area A_ON, the second control valve 52 is completely closed, and the total amount of working fluid discharged from the hydraulic pump 2 is reduced from the output port P2. It will be supplied to the external actuator. That is, the opening of the second control valve 52 gradually decreases in accordance with the rotation angle of the operation lever 4 toward the ON-region rotation end, and the flow rate supplied to the external actuator gradually increases. It will be. On the other hand, when the operating lever 4 is returned to the neutral position A_M, the switch SW of the electric motor 1 is turned off, the hydraulic pump 2 is stopped, and the supply of the working fluid is stopped. In this state, since the first control valve 51 and the main check valve 50 are closed, the fluid does not return from the external actuator. From here, the operation lever 4 is moved to the neutral position A_M.
When the screw rod 611 is turned to the off area A_OF side over the screw hole 613, the screw 611 is screwed inward according to the pitch of the screw hole 613, and the pushing member 612 connected to the screw rod 611 pushes the ball 511 of the first control valve 51. It is separated from the sheet 513. Then, the fluid returns to the tank 3 from the gap between the ball 511 and the seat 513, and the external actuator, for example, the cylinder contracts. The opening of the first control valve 51 is
The gap distance is determined by the gap distance between the ball 511 and the seat 513. Since the gap distance depends on the rotation angle of the operation lever 4, by adjusting this rotation angle,
By changing the flow rate returning to the tank 3, the speed at which the cylinder contracts can be adjusted. Therefore, the hydraulic device 1 according to the present embodiment
According to 00, when the electric motor 1 is started, the second control valve 52 is always opened at first, and the working fluid discharged from the hydraulic pump 2 is not immediately supplied to the external actuator. The opening degree of the second control valve 52 changes according to the rotation angle of the operation lever 4 in the ON region A_ON, and the flow rate of the working fluid supplied to the external actuator can be controlled. Therefore, when starting the electric motor 1,
That is, when the hydraulic pump 2 is started, it is possible to suppress a shock or the like caused by supplying the working fluid to the external actuator at once. The operation lever 4 for operating the switch SW of the electric motor 1 is moved by the first and second interlocking mechanisms 61 and 62.
, So that it can be used commonly for the operation of the first and second control valves 52, so that the number of parts can be reduced.
Since the supply flow rate and the return flow rate to the external actuator can be controlled with a mechanically simple structure, it is possible to improve cost, reliability and the like. In addition, the first control valve 51 is provided on an extension of the rotation shaft 42 of the operation lever 4 and moves forward and backward along the axis L1.
2 moves forward and backward in a direction orthogonal to the rotation axis L1, so that the degree of freedom in the arrangement position of the second control valve 52 increases,
The device can be made compact. The present invention is not limited to the above embodiment. For example, as shown in FIG. 5, a ball BB and a rod LL may be used in place of the poppet, and the cross section of the threaded rod is not limited to an ellipse. May be formed. In addition, other structures of the interlocking mechanism are conceivable, and it goes without saying that various modifications such as the outer shape of the apparatus and the arrangement position of each member are possible. According to the present invention described in detail above, the opening of the control valve is changed in accordance with the turning angle of the operating lever in the ON region, so that even when the electric motor is started, the operation of the hydraulic pump is stopped. Since it is possible to prevent the discharged working fluid from being immediately supplied to the external actuator,
That is, when the hydraulic pump is started, a shock or the like caused by supplying the working fluid to the external actuator at once can be suppressed. Further, since the operating lever for operating the electric motor is also used for operating the control valve by using the interlocking mechanism, the number of parts can be reduced, and the cost and reliability are excellent. It can be. In addition, since the control valve moves back and forth in a direction different from the rotation axis of the operation lever, the degree of freedom of the arrangement position of the control valve is increased, and the apparatus can be made compact.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a front view of a hydraulic device according to an embodiment of the present invention. FIG. 2 is a side view of the hydraulic device in the embodiment. FIG. 3 is a hydraulic circuit diagram of the hydraulic device according to the embodiment. FIG. 4 is a schematic longitudinal sectional view showing the internal structure of the hydraulic device in the embodiment. FIG. 5 is a schematic longitudinal sectional view showing the internal structure of a hydraulic device according to another embodiment of the present invention. [Description of Signs] 1 ... Electric motor P1 ... Discharge port 2 ... Hydraulic pump 3 ... Tank A_ON ... On area A_OF ... Off area 4 ... Operation lever R3 ... Communication path (second branch path) L1 ... rotation axis 52 ... control valve (second control valve) 62 ... interlocking mechanism (second interlocking mechanism)

Claims (1)

Claims: 1. An electric motor, a hydraulic pump driven by the electric motor to discharge a fluid from a discharge port, a tank, and a rotary operation to a predetermined on area activates the electric motor. An operation lever that stops the electric motor when rotated to an off area that is set separately from the on area; a communication path that communicates a discharge port of the hydraulic pump with the tank; and a rotation axis of the operation lever. Move in different directions from
A hydraulic valve, comprising: a control valve that controls a flow rate of a fluid passing through the communication path; and an interlocking mechanism that interlocks a rotation operation of the operation lever in an ON region with an advance / retreat operation of the control valve. .