JP2647404B2 - Pump device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a pump device having a check valve closed by its own weight.

[Prior Art] The above check valve is disclosed in, for example, Japanese Patent Application Laid-Open No. 60-81490.
In the gazette of Japanese Patent Application Laid-Open Publication No. H10-260, it is disclosed. The prior art disclosed in the publication will be described with reference to FIG. 3 and FIG.

Third is a pump device U using such a check valve.
The pump device U includes a casing C. The casing C is provided with a liquid inlet I and a liquid outlet O. A check valve 1 is provided at the inner end of the inflow port I, and a strainer 2a (4th
(Figure 2). As shown in FIG. 4, the check valve 1 is of a type that is closed by gravity, and a stopper 27 is provided above the check valve 1 to prevent the valve from being detached during transportation or operation of the pump device. In FIG. 3, a pump 3 is provided substantially at the center of the casing C. A known internal gear pump is used as the pump 3. The pump 3 has a suction port and a discharge port, and a liquid passage 10 connecting the chamber 2 and the suction port is formed in the casing C. The discharge port of the pump 3 communicates with the gas-liquid separator 4. A liquid path is formed so that the liquid flowing outside the gas-liquid separation device 4 in the radial direction, that is, the liquid containing no bubbles, flows into the chamber 5 provided with the strainer on the outflow side. Between the outlet O, a control valve 6 is provided. This control valve 6
When the pump is driven, the valve is opened against the spring to open the valve and the liquid flows out.After refueling is stopped, the liquid can flow backward when the pressure in the pipe connected to the outlet increases due to temperature rise etc. Have been. A bypass valve 12 is provided in a liquid passage 11 for the liquid flowing radially outward of the gas-liquid separator 4, and the liquid passage 11 communicates with a suction port of the pump 3. On the other hand, gas-liquid separator 4
The liquid containing air bubbles flowing inward in the radial direction is communicated with a gas-liquid separation chamber (not shown in FIG. 3). The gas separated in the gas-liquid separation chamber is discharged from the air vent 14, and the separated liquid is supplied to the strainer chamber 2 on the inflow side.
Flows in the liquid passage communicating with the fluid.

When the pump 3 is rotated, the liquid flows from the inflow port I through the check valve 1, the inflow-side strainer chamber 2, the pump 3, the gas-liquid separator 4, the outflow-side strainer chamber 5, and the control valve 6. Discharged. A part of the liquid from the gas-liquid separator 4 is bypassed to the pump 3 through the bypass valve 12. This is because the gear pump 3 determines the amount of tooth discharge depending on the number of revolutions thereof, so that the gear pump 3 responds to a change in the discharge amount. In the gas-liquid separation device 4, the liquid containing gas flows into the gas-liquid separation chamber, where the gas is discharged from the air vent 14, and the liquid is returned to the strainer chamber 2 on the inflow side.

Next, the check valve disclosed in the above publication will be described with reference to FIG.

The check valve 1 is roughly constituted by a disc-shaped valve body 21, a valve rod 22, and a double-circular tubular valve seat 23. Valve body 21 and valve stem
22 are integrally connected to each other, and in the illustrated embodiment, the nut is
Integrated by 21a. The valve seat 23 has a cylindrical shape, a valve seat portion 23a having a chamfered upper end, a valve stem guide portion 23b formed in a cylindrical shape inside the valve seat portion 23a, and a valve seat guide portion 23b.
It is composed of a support projection 23c supported by 23a and a flange 23d. The flange 23d is in contact with the casing C via the packing 26, and the opposite surface is in contact with the pipe flange 24. And casing C and packing
The flange 26, the flange 23d, and the flange 24 are connected by a bolt 25. The valve stem 22 is loosely fitted in the inner hole of the valve stem guide portion 23b and is guided and supported so that it can freely move up and down.
Since the valve stem 22 is guided by the valve stem guide portion 23b, the vertical movement of the valve body 21, that is, the opening and closing operation of the valve is accurately performed in a certain vertical axis direction.

In FIG. 4, the valve opening limiting piece is configured as a stopper 27 having an L-shaped cross section, and this stopper 27 is provided so as to be located immediately above the check valve 1.
The maximum distance between the valve stem 22 and the stopper 27 is
The interval is set so as not to escape from b. The flange 27a of the stopper 27 is connected to the lid 16 of the inflow strainer 2 by a bolt, that is, a mounting screw 28. Therefore, as shown in the figure, the flange 27a of the stopper 27 is fixed together with the strainer 2 by the mounting screw 28. . Since the stopper 27 is located immediately above the valve body 21, when the check valve 1 is turned upside down from the position shown in FIG. 4 during transport of the pump, or when the oil liquid suddenly flows in, etc. In FIG. 4, even if the valve body moves upward in FIG. 4, the amount of movement is restricted by contacting the stopper 27. Here, the distance from the position where the valve temperature zone 21 abuts the valve seat 23 to the stopper 27 is shorter than the length of the valve rod 22 inserted through the valve rod guide portion 23b.
The valve stem 22 does not come off the valve stem guide portion 23b even when the valve stem 22 moves (rises) until it contacts the stopper 27.

The valve body 21 is not biased by a spring or the like,
It is in contact with the valve seat 23 by its own weight. Therefore, the resistance to open the check valve 1 when the liquid flows in, that is, the resistance to move the valve body 21 upward is very small.

The diameter of the valve body 21 is configured to be slightly larger than the inner diameter of the valve seat 23a. When the pump stops, etc., the valve body 21 is
This is for surely preventing the liquid from dropping (backflow) from the inflow port I in the state where the liquid is in contact with a, that is, when the check valve 1 is closed.

In the prior art described in Japanese Patent Application Laid-Open No. 60-81490, the only means for connecting the stopper 27 and the strainer to the lid 16 is the mounting screw 28, and when the mounting screw 28 is fastened, the strainer is strongly tightened. And the flange 27a of the stopper 27 rotates, and the position of the stopper 27 may fluctuate. As a result, the stopper 27 is not located immediately above the check valve 1, and the valve body 21 comes off.

Further, even if the mounting screw 28 is loosened while the pump 3 is being driven, the position of the stopper 27 fluctuates, and the function as the stopper cannot be achieved.

[Problems to be Solved by the Invention] Accordingly, an object of the present invention is to provide a pump device that can easily and reliably mount a check valve at an appropriate position even if a stopper is limited together with a strainer to limit upward movement of a check valve. I do.

[Means for Solving the Problems] According to the present invention, a pump, a gas-liquid separation device, and a gas-liquid separation chamber are provided in a casing, an inlet check valve is provided, and a control valve is provided at an outlet. Wherein the inlet is open to the lower surface of the casing, the check valve is closed by gravity, and comprises a valve stem and a valve seat, wherein the inlet is inserted into the casing via the check valve. The chamber is partitioned and communicates with a chamber communicating with the suction side of the pump, and a lid of a strainer is attached to a side surface of the chamber so as to be openable and closable on a casing, and a stopper for limiting upward movement of the check valve is provided on the lid. In the pump device attached together with the strainer, the stopper has a flange portion for attaching the stopper to the lid, and the lid has a projection formed with a female screw portion on the inside and a rotation. An anti-rotation boss is provided, and a hole for a mounting screw and another hole into which the anti-rotation boss is provided are provided in the flange portion, and penetrate through the hole for the mounting screw to be screwed into the female screw portion. Has mounting screws.

[Explanation of Operation and Effect] Accordingly, with the lid removed, the holes for the mounting screws of the flange portion and the female screw portions are aligned from inside, and the rotation preventing boss is fitted into another hole. Then, if the mounting screw is screwed into the female screw portion to fix the flange portion, the stopper can be set at a correct position on the lid, and the strainer can be fixed at the same time.

In this way, the stopper does not rotate because the anti-rotation boss and another hole are connected during both the mounting operation and the operation after mounting, and the stopper always stays in the correct position. doing. Therefore, even if the strainer is strongly tightened, the stopper does not rotate, and the mounting workability can be improved.

Further, since the screw portion has a projection, the strainer can be attached without interfering with other parts when attaching the strainer.

Embodiment An embodiment of the present invention will be described below with reference to FIGS. 1 and 2. 1 and 2, the same members as those in FIGS. 3 and 4 are denoted by the same reference numerals and described.

FIG. 1 shows an embodiment in which a stopper 27 of a check valve according to an embodiment of the present invention is attached to a lid 16 of an inflow strainer, and a flange portion 27a of the stopper 27 has a hole 30 through which an attachment screw 28 passes. A hole 34 into which the rotation prevention boss 32 is fitted is formed. At the time of mounting, the projection 38 having the female screw portion 36 formed inside and the hole 30 for the mounting screw are aligned, and the mounting screw 28 and the female screw portion 36 inside the projection 38 are screwed together and rotated. The prevention boss 32 is fitted into the hole 34. Therefore, it is easy to position the stopper 27 in a proper position on the lid 16, and even if the mounting screw 28 is firmly fastened, the action of the rotation preventing boss 32 and the hole 34 causes the flange portion 27a to rotate (rotate). And the position of the stopper 27 is not displaced.

FIG. 2 shows a case where the stopper 27 according to the embodiment of FIG. 1 is used for the check valve 1 of the pump device. As described above, the position of the stopper 27 is not displaced and is always located above the valve body 21. Since the distance L between the valve body 21 and the stopper 27 is shorter than the length 1 of the valve stem 22 below the valve stem guide 23b, the valve body 21 does not come off.

The operation of the check valve 1 is substantially the same as that described with reference to FIG. 4, and a detailed description thereof will be omitted.

[Effects of the Invention] As described above, the present invention has the following excellent effects.

(I) The stopper does not rotate even if the strainer is strongly tightened.

(Ii) Should the mounting screws become loose, the position of the stopper will not change.

(Iii) The work of mounting the strainer and the stopper is easy, no special jig is required, and the workability is improved.

(Iv) Therefore, the check valve of the pump device can be prevented from falling off or malfunctioning, and no oil flows out of the pump device.

[Brief description of the drawings]

1 is a perspective view showing an embodiment of a stopper of a check valve according to the present invention, FIG. 2 is a sectional view showing a state in which the stopper of FIG. 1 is applied to a pump device, and FIG. 3 is provided with a check valve. FIG. 4 is a plan view of the pump device, and FIG. 4 is a sectional view similar to FIG. 2 showing a state in which a stopper of a conventional check valve is attached to the pump device of FIG. 1 ... Check valve, 3 ... Pump, 27 ... Stopper, 27
a ... stopper flange, 28 ... mounting screw, 30 ...
Mounting screw through hole, 32: Rotation prevention boss, 34: Rotation prevention boss fitting hole

Claims (1)

(57) [Claims] A pump, a gas-liquid separation device, and a gas-liquid separation chamber are provided in a casing, a check valve is provided at an inflow port, a control valve is provided at an outflow port, and the inflow port is provided with a casing. Opened on the lower surface, the check valve is closed by gravity, and includes a valve stem and a valve seat, and the inflow port is defined in the casing via the check valve and communicates with a suction side of a pump. A pump device in which a strainer lid is attached to a side surface of the chamber so as to be openable and closable, and a stopper for limiting upward movement of the check valve is attached to the lid together with the strainer. The stopper has a flange portion for attaching the stopper to the lid, and the lid is provided with a projection having a female screw portion formed therein and a rotation preventing boss; The mounting portion has a mounting screw hole and another hole into which the rotation preventing boss 4 is fitted, and has a mounting screw that passes through the mounting screw hole and is screwed into the female screw portion. Pumping equipment.