JP3107621B2 - Rotary pump unit - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotary pump unit in which a tank, a valve body, a rotary pump and an electric motor are integrated.

[0002]

2. Description of the Related Art As a rotary pump unit of this kind, the invention described in Japanese Utility Model Laid-Open No. 3-61175 has been conventionally known. In this conventional rotary pump unit, a rotary pump is disposed between a tank containing an electric motor and a valve body containing a valve system. Therefore, an oil passage connecting the valve body and the tank had to be an external pipe passing outside the rotary pump.

[0003]

However, if the oil passage connecting the valve body and the tank is formed as an external pipe as described above, the number of piping steps is added to the process of assembling the rotary pump unit. There was a problem that the number of assembly steps was increased. Also, since the external piping is not so thick, if something hits it, it may bend easily and cause oil leakage. An object of the present invention is to provide a rotary pump unit that does not require external piping between a tank and a valve body.

[0004]

The present invention comprises a tank,
An electric motor built in the tank, a rotary pump connected to the electric motor, and a valve body containing a valve system for controlling the discharge oil of the rotary pump. The tank, the rotary pump and the valve body are connected. It is assumed that a rotary pump unit is used. While assuming the above units, the present invention is to the side of the tank
Fix the valve body to the lid of the combined electric motor.
And fix the rotary pump to this valve body.
On the other hand, the lid plate has a suction passage communicating with the tank and a suction passage.
Return flow path, and the valve body has suction
Forming a suction port and a return port, and
To communicate the tank with the suction port, and
It is characterized in that the tank and the return port communicate with each other.

[0005]

The present invention is constructed as described above, so that the tank and the valve body can be directly connected. This direct connection allows oil to flow directly between the tank and the valve body via the suction oil passage and the return oil passage formed in the lid of the electric motor.

[0006]

According to the rotary pump unit of the present invention, the tank and the valve body can be communicated with each other without using external pipes. All problems such as oil leaks have been resolved.

[0007]

The illustrated embodiment is an example of a rotary pump unit used for a single-acting cylinder.
And a rotary pump P is connected to the valve body B. As shown in FIG. 2, the electric motor M covers both sides of a cylindrical main body 1 with lid plates 2 and 3. The electric motor M is built in the tank T. That is, the rotor 4 is rotatably supported between the lid plates 2 and 3, and the stator 5 fixed to the inner periphery of the main body 1 is positioned outside the rotor 4. Further, an electric motor M coupled to one side of the tank T
The lid plate 3 has a suction passage 7 communicating with a suction port 6 formed in the valve body B, and a return passage 9 communicating with a return port 8 also formed in the valve body B.

As shown in FIGS. 4 and 5, the valve body B has a shaft hole 10 through which the motor shaft of the electric motor M passes. The motor shaft penetrating the shaft hole 10 is connected to the drive shaft of the rotary pump P so that the rotary pump P operates with the driving force of the electric motor M. In addition to the suction port 6 and the return port 8, the valve body B has a supply port 11 for communicating the suction port 6 with the pump P, and a discharge port 12 for communicating with the discharge side of the rotary pump P. , And an actuator port 13 communicating with the single-acting cylinder C.

A check valve 15 is provided in a flow path 14 between the discharge port 12 and the actuator port 13 to allow only the flow from the pump P to the single-acting cylinder C. In addition, a flow control valve 17 and a solenoid valve 18 are provided in a flow path 16 branched from the flow path 14 and connecting the actuator port 13 and the return port 8. The solenoid valve 18 has a normal position shown in the drawing, which allows only the flow from the return port 8 to the actuator port 13, and a switching position in which the flow from the actuator port 13 to the return port 8 is a free flow.

A filter 20 is provided in a flow path 19 between the suction port 6 and the supply port 11, and the filter 20 is exchangeably housed as follows. That is, as shown in FIG. 4, a concave portion 21 is formed in the valve body B, and the suction port 6 and the supply port 11 are communicated through the concave portion 21. A cap 23 is placed on the opening side of the recess 21 with a seal 22 interposed therebetween, and the cap 23 is
Is fixed to the side surface of the valve body B. This recess 21
The filter 20 is provided in a chamber 25 constituted by the combination of the filter 20 and the cap 23. The room 25 thus constructed is
The connecting direction of the tank T, the valve body B, and the pump P, that is, the axis direction of the electric motor is perpendicular to the connecting direction. Therefore, the cap 23 does not interfere with the tank T or the pump P, and the attaching / detaching operation of the cap 23 becomes easier accordingly.

The filter 20 has one end opened,
The other end is made into a cylindrical shape, and the supply port 1
A spring 26 is interposed between the outer end of the filter 20 and the cap 23 so as to prevent the filter 20 from coming off the inlet of the flow path 19, while completely covering the inlet of the flow path 19 on one side. A flange 20 a is formed around the opening of the filter 20, and the outer diameter of the flange 20 a is substantially equal to the inner diameter of the recess 21. Therefore, by inserting the flange 20a while aligning it with the concave portion 21 as shown in FIG.
A passage 27 is formed between the inner periphery of the filter 1 and the periphery of the filter 20. This passage 27 communicates with the suction port 6 side. In the figure, reference numeral 28 denotes a relief valve, which opens when the pressure on the side of the flow path 14 becomes equal to or higher than a set pressure,
This is for returning the pressure oil to the tank T via the flow path 16.

Next, the operation of this embodiment will be described. First, the case where the load W of the single-acting cylinder C is increased will be described. When increasing the load W, the electric motor M is driven after holding the solenoid valve 18 at the normal position shown in the figure. When the electric motor M is driven, the rotary pump P operates, and the hydraulic oil in the tank T flows into the suction port 6 via the suction passage 7 and passes through the filter 20 from the passage 27 to the passage 19. From which it is sucked into the rotary pump P via the supply port 11. The pump P that has sucked the hydraulic oil discharges the pressure oil to the discharge port 12, and the discharged pressure oil is supplied to the single-acting cylinder C by pushing and opening the check valve 15 of the flow path 14. W rises. If the pump P is stopped after moving the load W to a desired position, the load W can be held at that position.

From this load holding state, the solenoid valve 1
8 is switched to the switching position for free flow, the hydraulic oil of the single-acting cylinder C flows from the flow control valve 17 to the solenoid valve 18 →
The return port 8 is returned to the tank T via the return flow path 9. Therefore, the single-acting cylinder C descends under the action of the load W or its own weight. However, at this time, by adjusting the flow control valve 17 and controlling the return flow at that time, the descent speed of the single-acting cylinder C can be adjusted.

If the use of the rotary pump unit is repeated, dust or the like accumulates on the filter 20 and causes clogging. In such a case, the cap 23 is removed by loosening the bolt 24 and the filter 20 in the chamber 25 is removed.
Can be replaced. In particular, since the cap 23 does not interfere with the tank T or the pump P as described above, the attachment / detachment work becomes extremely simple. In the above-described embodiment, the case where a single-acting cylinder is used has been described.

[Brief description of the drawings]

FIG. 1 is a front view.

FIG. 2 is a partial cross-sectional view of the electric motor.

FIG. 3 is a side view of the electric motor.

FIG. 4 is a sectional view of a valve body.

FIG. 5 is a side view of the valve body.

FIG. 6 is a circuit diagram.

[Sign]

 M Electric motor T Tank B Valve body P Rotary pump 3 Lid plate 7 Suction channel 9 Return channel

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) F04C 11/00-15/04 321 F04C 2/08-2/352 F04B 21/00-23/14

Claims (1)

(57) [Claims] 1. A tank comprising: a tank; an electric motor built in the tank; a rotary pump connected to the electric motor; and a valve body containing a valve system for controlling oil discharged from the rotary pump. In a rotary pump unit that connects a pump and a valve body,
A cover is attached to the lid of the electric motor connected to the side of the tank.
While fixing the lube body, turn the valve body
The transfer pump is fixed while the lid plate is connected to the tank.
Forming a suction flow path and a return flow path through which
In the lube body, a suction port and a return port are formed,
Communicating the tank and the suction port via the suction flow path,
The tank and the return port are communicated through the return flow path.
A rotary pump unit characterized by the above-mentioned.