JPS6081480A - Pump - Google Patents

Abstract

PURPOSE:To prevent pressure rise while to improve the gas-liquid separation efficiency and measuring accuracy by constructing such that the air fialed to flow out into gas-liquid separation chamber is fed through bypass valve, bypass liquid path and pump to gas-liquid separation system. CONSTITUTION:The delivery port 3b of pump 3 is communicated to a gas-liquid separation device 4 while a bypass valve 12 is provided in a bypath for liquid flowing radially outward of said device 4 where said bypath is communicated with the suction port 3a of pump 3. The air not flowed out from said device 4 into a gas-liquid separation chamber (not shown) but stored at the upper portion will flow together with a portion of liquid flowed out through a path between the device 4 and an outer tube through bypass valve 12 and liquid bypath into the suction port 3a of pump then fed again through the delivery port 3b of pump and liquid path 18 to said device 4. Consequently, gas-liquid separation is promoted resulting in improvement of measuring accuracy.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a pump device implemented, for example, in a fuel supply system at a gas station.

As is well known, in a refueling system at a refueling station that handles volatile liquids such as gasoline, a pump device is provided with a device for separating gas mixed in the form of bubbles from the liquid. A device for separating gas mixed in this liquid is usually composed of a gas-liquid separation device and a gas-liquid separation chamber. A gas-liquid separator separates the liquid into a gas-rich liquid and a gas-free liquid, and only the gas-rich liquid is sent to the gas-liquid separation chamber. On the other hand,
The liquid that does not contain gas is allowed to flow out from the outlet. Further, a portion of the liquid flowing out from the pump is returned to the inlet of the pump via a bypass passage having a bypass valve. The reason for providing a bypass valve in this way is that, for example, when the discharge nozzle installed downstream of the outlet is throttled or closed, high pressure will be generated on the discharge side of the pump and the piping or casing will be damaged. This is to prevent the motor from being overloaded.

That is, when the pressure on the outlet side reaches a certain level or higher, the bypass valve opens to return the liquid to the suction side of the pump, thereby preventing the occurrence of abnormally high pressure on the outlet side. The purpose of the bypass valve can be achieved by providing communication between the outlet side of the pump, that is, the discharge side, and the suction side of the pump. In the prior art, a bypass passage 4 is provided that communicates the discharge side and suction side of the pump.

As a result of various studies in the present invention, it has been found that a bypass passage is provided at the rear of the gas-liquid separation device, thereby obtaining a more complete pump device for the gas-liquid separation device.

That is, an object of the present invention is to provide a pump device that can suitably perform gas-liquid separation with a simple configuration.

In carrying out the present invention, it is preferable that the bypass liquid path flowing into the bypass valve is located at the upper part of the flow path after leaving the gas-liquid separation device. If this is done, the air contained in the liquid will accumulate in one part when the pump is stopped, and the air accumulated at the top of the gas-liquid separator while the pump is stopped will be removed before the pump is started and the liquid is discharged. For example, after C-bond 1 is started at a gas station and before it is refueled from the discharge nozzle, the discharged fluid from the pump is circulated through the bypass passage, and during that time the air that has accumulated in the upper part is mixed with the fluid. It circulates, is separated by a gas-liquid separator, and flows out to a gas-liquid separation chamber. Further, even when liquid is being discharged from the pump, for example, when the discharge nozzle is being throttled, a small amount of liquid is being circulated through the bypass passage. At this time, the air that was not separated by the gas-liquid separator floats to the top of the gas-liquid separator, but this air enters the pump through the bypass valve, is separated by the gas-liquid separator again, and flows out to the gas-liquid separation chamber. do. Therefore, the present invention can improve the gas-liquid separation ability.

Embodiments of the present invention will be described below with reference to the drawings.

Figures 1 to 4 illustrate the implementation of the present invention! Kobong device U
This pump device U is equipped with a casing C. The casing C is provided with a liquid inlet 1 and an outlet O. A check valve 1 is provided at the inner end of the inlet 1, and opens into a chamber 2 provided with a strainer 2a on the inlet side. As shown in the figure, the check valve 1 is of a type that closes by gravity, and a stopper 50 is provided above the check valve 1 to prevent the valve from coming off during transportation or operation of the pump device. A pump 3 is provided approximately in the center of the casing C. In the illustrated embodiment pump 3
A known internal gear pump is used. This pump 3 has a suction port 3a and a discharge port 3b, and a liquid path 10 is formed in the casing C to connect the chamber 2 and the suction port 3a.

A discharge port 3b of the pump 3 communicates with a gas-liquid separator 4, which will be described later. A liquid path is configured such that the liquid flowing outside in the radial direction of the gas-liquid separator 4, that is, the liquid that does not contain bubbles, flows into a chamber 5 provided with a trainer 5a on the outflow side, and a strainer chamber 5 on the outflow side. A control valve 6 is provided between the outlet port 0 and the outlet port 0. This control valve 6 opens the valve against the spring 6a when the pump is driven, and when the liquid flows out and the pressure in the piping connected to the outlet becomes high due to temperature rise, etc. after the oil supply is stopped, the spring 6b The small valve 6C is opened to allow the liquid to flow backwards. Bypass liquid path 11 for liquid flowing radially outward of the gas-liquid separator 4
is provided with a bypass valve 12, and this bypass liquid path 11
is in communication with the suction port 3a of the pump 3.

On the other hand, the liquid containing bubbles flowing inside the gas-liquid separator 4 in the radial direction passes through the flow rate restriction valve 7 and flows into the wave path 13. This flow path 13 is formed in the cover 16. This liquid path 13 communicates with a gas-liquid separation chamber 8, which will be described later. The gas separated in the gas-liquid separation chamber 8 is discharged from the air vent 14, and the liquid from which the gas has been separated flows into the liquid path 15. This liquid passage 15 is provided with a check valve 9, and this liquid passage 15 is connected to the strainer chamber 2 on the inflow side.
is connected to.

A cover 16 is provided on a pair of opposing surfaces of the casing C. This is so that only one pair of surfaces needs to be opened for repair after installation.

Therefore, when the pulley 17 is rotated by the motor to rotate the pump 3, the liquid flows from the inlet 1 to the check valve 1, the strainer chamber 2 on the inflow side, the bong 13, the gas-liquid separator 4, the strainer chamber 5 on the outflow side, and the control. It passes through the valve 6 and is discharged from the outlet O. Further, a part of the liquid from the gas-liquid separator 4 passes through the bypass valve 12 and is bypassed to the pump 3.

This is because the amount of liquid pumped from the gear pump 3 is determined by its rotational speed, so it is necessary to deal with changes in the amount of discharge. On the other hand, in the gas-liquid separation device 4, the liquid containing gas flows through the flow rate restriction valve 7 to the gas separation chamber 8, where the gas is released from the air vent 14, and the liquid passes through the check valve 9 to the strainer chamber on the inflow side. It will be returned to 2.

Next, a gas-liquid separation device of a pump device suitable for implementing the present invention will be described.

As shown in FIG. 4, the wave path 18 from the pump outlet 3b leading to the gas-liquid separator 4 communicates with a swirl chamber S configured to guide the liquid in the tangential direction to the gas-liquid separator 4 (
(See Figure 9). In Figures 5 and 9, this spiral chamber S
is extended by an outer cylinder 20, and its end 20a is open, and the strainer chamber 5 and flow path 11 on the outflow side are extended.
It communicates with

Therefore, the gas-free liquid flowing out from the end 20 of this outer cylinder 20 flows from the outside to the inside of the strainer 5, flows into the chamber 23 formed at the axial end of the strainer 5, and then passes through the control valve 6. It flows out from the outlet O.

On the other hand, inside the inner cylinder 21 of the gas-liquid separation device 4, a valve body 24 and a valve seat 25 constituting the flow rate limiting valve 7 are provided, and the valve body 24 is pressed in the opening direction by a spring 26. This valve body 2
4 has an opening 22 in the center and an opening 27 in the side. When the amount of gas contained in the liquid increases, the valve body 24
When the pressure on the inlet side of the valve body 24 is low and there is little gas, the pressure on the inlet side of the valve body 24 increases. Therefore, when the amount of air contained in the liquid increases, due to the difference in silicon strength between the front and rear parts (the valve body 24 moves to the left in the drawing), a large amount of liquid (including air bubbles) flows through the opening 22.
27 and flows into the liquid path 13 through the passage 28 of the valve seat 25. When the content of bubbles decreases, the valve body 24 moves to the right due to the pressure of the inflowing liquid, and the liquid flows out only from the central opening 22. The flow rate is therefore controlled.

6 and 7 show a gas-liquid separation chamber 8 implemented in the present invention.
A preferred embodiment is shown.

The gas-liquid separation chamber 8 has a liquid path 13 at a position facing the outlet hole 30 of the liquid path 13, that is, the inlet of the gas mixture.
Shelf section 31 that alleviates the inflow force of the liquid containing bubbles flowing out from the shelf section 31
is provided. This shelf 31 extends from the casing C in a substantially horizontal direction. Therefore, the liquid flowing out from the outlet hole 30 does not flow directly into the liquid accumulated in the upper part of the chamber 8, but once flows into the shelf part 31 and quietly flows downward along the wall surface. Therefore, there is no foaming in the gas-liquid separation chamber 8, which prevents malfunction of the float due to foaming, and also prevents foam from flowing out from the air bend pipe 14. Inside the gas-liquid separation chamber 8 is a float 3 that can rotate around a pivot point 33.
2 is provided. This float 32 is interlocked with a valve 34 that controls the closing and closing of the liquid path connected to the inflow side of the pump, that is, the liquid outflow path 15.

When liquid accumulates in the gas-liquid separation chamber 8, the float 32 moves to the pivot point 33.
Since the valve body 34 is rotated counterclockwise around the center and the valve body 34 is opened, the liquid in the gas-liquid separation chamber 8 flows out into the liquid path 15. Note that 35 in the figure is a stopper.

As shown in FIG. 8, a liquid path 15 from this gas-liquid separation chamber 8
is provided with a check valve 9. The liquid passage 15 communicates with the strainer chamber 2 on the inflow side via the check valve 9. Therefore, the liquid in the chamber 2 will not flow back into the gas-liquid separation chamber 8 when the pump is stopped.

FIG. 9 shows an embodiment of the bypass valve 12 implemented in the present invention.

That is, the liquid flowing out from the passage between the outer cylinder 20 and the inner cylinder 21 of the gas-liquid separator 4 flows toward the strainer chamber 5 on the outflow side, and the excess liquid passes through the bypass liquid path 11 and passes through the bypass valve. It flows towards 12.

This bypass valve 12 includes a valve body 40 pressed by a spring 42 and a valve seat 41 on which the valve body 40 is seated. Therefore, when the pressure in the wave passage 11 on the first flow side of the valve body 40 increases, the valve body 40 opens against the spring 42, and the liquid flows into the chamber 44 on the downstream side of the valve body 40. This chamber 44 communicates with the suction port 38 of the pump 3. A spring seat 45 that locks one end of the spring 42 can be positioned by an adjustment screw 46, so that the hydraulic pressure at which the valve body 40 opens can be adjusted.

The inlet of the bypass valve 12, that is, the inlet of the bypass liquid path 11 leading to the pump suction port 3a, communicates with the upper part 4a of the flow path after flowing out from the gas-liquid separation device 4.

The gas-liquid separator 4 does not flow into the gas-liquid separation chamber 8, and the upper part 4a
The air accumulated in the pump flows into the liquid part flowing out from the passage between the outer cylinder 20 and the inner cylinder 21 and into the inlet of the bypass valve 44, passes through the bypass valve 12 and the bypass liquid path 11, and then flows into the pump suction. The liquid flows into the port 3a and is then supplied to the gas-liquid separation device 4 again via the pump discharge port 3b and the liquid path 18. In this way, the air that did not flow out into the gas-liquid separation chamber 8 is collected by the bypass liquid path 11 and sent to the gas-liquid separation device 4 again, thereby increasing the efficiency of gas-liquid separation.

As described above, according to the present invention, the inlet of the bypass valve is provided so as to be located above the flow path of the outflow line from the gas-liquid separator, so that the near air which does not flow out into the gas-liquid pre-chamber is Since the liquid is supplied to the gas-liquid separation device again via the bypass valve and pump, in addition to the role of the conventional bypass liquid path and bypass valve, which is to prevent pressure rise on the discharge side, it also improves the gas-liquid separation device. (difficult) action is also performed. Further, by promoting the gas-liquid separation device, it also contributes to improving measurement accuracy.

[Brief explanation of drawings]

Fig. 1 is a front view of a pump device embodying the present invention, Fig. 2 is a rear view thereof, Fig. 3 is a plan view thereof, Fig. 4 is a sectional view at 6 is a cross-sectional view showing a part of the liquid separation device; FIG. 6 is a vertical cross-sectional view showing a part of a gas-liquid separation chamber;
FIG. 7 is a cross-sectional view showing the gas-liquid separation chamber, FIG. 8 is a cross-sectional view showing the inverse 11 valve, and FIG. 9 is a cross-sectional view showing the bypass valve. 1...Check valve 2...Strainer on the inflow side 3
... Pump 4 ... Gas-liquid separation device 5 ... Strainer on the outflow side 6 ... Control valve 7 ... Flow rate restriction valve 8 ... Gas-liquid separation chamber 9 ... Check valve 11.
... Bypass liquid path 12 ... Bypass valve S ... Volute chamber 20 ... Outer cylinder 21 ... Inner cylinder Patent applicant Tokyo Tatsuno Co., Ltd. Fig. 3 Fig. 4 Fig. 6 Fig. 7 Fig. 9 figure

Claims (1)

[Claims] A pump device in which the outflow side of a gas-liquid separation device that communicates with the discharge side of the pump and the inlet of the pump are communicated via a bypass valve C.