JP2007239611A - Pump unit - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To surely open and close a relief valve for discharging a gas-enriched liquid separated from a liquid into a gas separating chamber. <P>SOLUTION: In the relief valve 38, when the gas-enriched liquid is accumulated at the upper part of a cyclone 32, a pressure in a pressure chamber 114 is reduced by bubbles, and a valve element 100 is slid in the Xb direction by the spring force of a coiled spring 102. When the valve element 100 is returned to a valve opening position, a cylindrical valve part 1001 extends through an inflow port 110 and an outflow port 120, and the groove 100d of the valve element 100 is communicated with the inflow port 110 and the outflow port 120 while facing each other. The gas-enriched liquid accumulated at the inflow port 110 is pushed up by a hydraulic pressure from the cyclone 32, and discharged from the groove 100d of the valve element 100 to the gas separating chamber 60 through the outflow port 120, a bypass passage 122, a through hole 61, and a pipe member 62. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a pump unit, and more particularly to a pump unit including a gas-liquid separation device that separates a liquid and a gas contained in a fluid in a system for supplying the fluid.

  For example, an oil supply device used in a gas station is required to be as small as possible due to space constraints, and accordingly, a small pump unit is also required. On the other hand, gas is often mixed in gasoline or the like handled at a gas station, and a pump unit equipped with gas-liquid separation means is required.

  Therefore, conventionally, in order to meet the above-mentioned demands, a casing having an inlet and an outlet is provided, and a pump for sucking fluid from the inlet and a fluid discharged from the pump are swirled in the casing. A gas-liquid separation device that separates the gas-enriched liquid and a gas separation chamber that separates the gas from the gas-enriched liquid separated by the gas-liquid separation device are provided, and the liquid separated by the gas-liquid separation device A pump unit that guides to the outlet through a filter chamber and a check valve, returns the liquid separated in the gas separation chamber to the suction port side of the pump, and discharges the separated gas out of the casing; It has been developed (see, for example, Patent Document 1).

  According to this pump unit, it is possible to reduce the size by arranging the components in one casing, and of course, the gas mixture is extremely small due to the double gas-liquid separation by the gas-liquid separation device and the gas separation chamber. The liquid can be supplied.

  By the way, according to such a pump unit, the flow path for sending the gas-enriched liquid from the gas-liquid separator to the gas separation chamber is partially restricted to restrict the inflow of the separated liquid from the gas-liquid separator. Therefore, for example, when a trouble occurs on the liquid tank side connected to the inlet of the casing, for example, when a large amount of air is sucked into the casing due to a crack in the pipe between the liquid tank and the inlet, The escape of air through the flow path is insufficient and the casing is filled with air.As a result, the air leaks to the outlet, and the flow meter connected to the outlet measures the air. An error occurs in the measurement of the amount of oil.

  Therefore, for example, in the one disclosed in the above publication, a flow restriction valve is provided in the flow path for sending the gas-enriched liquid from the gas-liquid separation device to the gas separation chamber, and the flow rate is supplied to the valve body constituting this flow restriction valve. In addition to providing a small opening for throttling, the valve body is normally urged in the valve opening direction by a spring, and the valve body is opened by the pressure difference before and after the flow control valve when a large amount of air is sucked in so that air can escape. I have to.

  However, according to the air escape countermeasure described in the above publication, since the portion where the flow control valve is provided is in a narrow flow path for sending the gas-enriched liquid, the size of the opening area when the valve body is opened However, there is a certain limit, and when a large amount of air close to 100% is inhaled, the escape of air is still insufficient, and the air may leak out to the outlet.

As a means to solve such problems, a throttle part is formed in the middle of the flow path for sending the gas-enriched liquid from the gas-liquid separator to the gas separation chamber, and the bypass part is bypassed to form a bypass flow path in parallel. There has been proposed a pump unit having a configuration in which a relief valve that opens the bypass channel in response to a pressure drop of the gas-enriched liquid from the gas-liquid separator is provided in the bypass channel (see, for example, Patent Document 1).
JP 60-81481 A JP-A-8-4660

  However, in the configuration provided with the relief valve, the valve body made of a float is held in a closed state by the hydraulic pressure, and when the air accumulates, the hydraulic pressure disappears and the valve body operates to open. For example, when the gas-liquid separation device changes from a state where there are almost no bubbles (only liquid) to a state where the gas-liquid separation device is filled with gas, the float itself is liquid if it is light. May stick to the valve seat of the bypass passage. In that case, the air in the gas-liquid separator cannot be discharged quickly, and as a result, the gas-liquid separator cannot perform gas-liquid separation.

  Moreover, in order to prevent such a problem, the float can be enlarged to increase the weight of the float itself to prevent sticking to the valve seat. On the other hand, the space in which the float is stored as the float becomes larger As a result, the casing of the pump unit becomes larger and it becomes difficult to secure a space for storing it in the fueling device.

  In view of the above circumstances, an object of the present invention is to provide a pump unit that solves the problem.

  In order to solve the above problems, the present invention has the following means.

According to the first aspect of the present invention, in a casing having an inlet and an outlet, a pump that sucks fluid from the inlet, and gas-liquid separation that separates the fluid discharged from the pump into a liquid and a gas-enriched liquid An apparatus, and a gas separation chamber for separating a gas from the gas-enriched liquid separated by the gas-liquid separation apparatus,
A flow path for sending a gas-enriched liquid from the gas-liquid separator to the gas separation chamber, and a relief valve that opens the flow path in response to a pressure drop of the gas-enriched liquid from the gas-liquid separator, In the pump unit that guides the liquid separated by the gas-liquid separation device to the outlet and discharges the gas separated in the gas separation chamber to the outside of the casing by opening the relief valve, the relief valve includes: The valve body that receives the pressure supplied to the flow path and slides in the flow path and moves to the valve closing position to communicate the flow path and the gas-liquid separation device, and the valve body is opened. And an urging member for returning to the valve position.

  The invention according to claim 2 is characterized in that the valve body is a spool having a groove formed on the outer periphery thereof for communicating the bypass flow path and the gas-liquid separator.

  The invention according to claim 3 is characterized in that the valve body has a through hole for supplying a gas-enriched liquid from the gas-liquid separator to the gas separation chamber.

  According to the present invention, the relief valve receives pressure supplied to the flow path, slides in the flow path and moves to the valve open position, thereby communicating the flow path and the gas-liquid separation device; And a biasing member that returns the valve body to the closed position, so that the problem that the valve body sticks to the valve seat and cannot be opened like a valve using a float can be solved. The valve body can be reliably opened and closed in accordance with the change in hydraulic pressure.

  The best mode for carrying out the present invention will be described below with reference to the drawings.

  FIG. 1 is a longitudinal sectional view showing an embodiment of a pump unit according to the present invention. FIG. 2 shows the structure of the pump unit, and is a cross-sectional view taken along the line II-II in FIG. 3 is a cross-sectional view taken along the line III-III in FIG. 4 is a cross-sectional view taken along the line IV-IV in FIG. FIG. 5 is a sectional view taken along the line VV in FIG. FIG. 6 is a side view showing the pump unit as a partial cross section.

  As shown in FIGS. 1 to 6, the casing 10 of the pump unit has an inlet 11 at the lower part and an outlet 12 at the upper part, and is integrally cast from an aluminum alloy. A suction chamber 13 is formed on the lower side of the casing 10 so as to face the inflow port 11, and a valve assembly 16 including a strainer 14 and a suction-side check valve 15 is disposed in the suction chamber 13. . On the other hand, a pump chamber 18 communicating with the suction chamber 13 via a flow path 17 (see FIG. 4) is formed on the upper side in the casing 10. The pump chamber 18 has a vane pump (rotary pump). ) 19 is provided. The pump 19 includes a bottomed cylindrical main body 20 fitted in the pump chamber 18. The main body 20 has a suction port 21 connected to the flow path 17 and a discharge port connected to another flow path 30 described later. An outlet 22 is provided.

  A rotor 23 is disposed in the main body 20 of the pump 19, and the rotor 23 is fixedly attached to a rotary shaft 24 in which the eccentric position of the main body 20 is extended. The rotating shaft 24 is rotatably supported by a bearing portion 25 formed integrally with the inside of the casing 10 and a bearing portion 26a formed integrally with the lid body 26 covered on the outer wall of the casing 10. The pump chamber 18 and the main body 20 are partitioned as a sealed chamber by closing the opening 10 a of the casing 10 with a lid 26. A plurality of vanes 27 are radially mounted on the rotor 23 so as to be slidable in the radial direction, and each vane 27 is provided at a base end thereof by a ring 28 disposed in a recess 23 a provided on both side surfaces of the rotor 23. Is supported. A pulley 29 that is driven to rotate by a motor (not shown) is attached to one end of the rotating shaft 24 that extends outside the casing 10.

  In the pump 19, when the pulley 29 is rotated by the operation of a motor (not shown), the rotation is transmitted to the rotor 23 via the rotating shaft 24, and each vane 27 is slidably contacted with the inner peripheral surface of the main body 20. Rotate while letting At this time, since the rotor 23 rotates around the eccentric position with respect to the main body 20, the volume of each chamber partitioned by the vane 27 repeatedly expands and contracts, thereby generating a negative pressure on the suction side in the main body 20. Therefore, if the inflow port 11 is connected to the tank, the fluid in the tank is transferred from the inflow port 11 through the strainer 14, the suction side check valve 15, the flow path 17 and the suction port 21 by the rotation of the rotor 23. And is discharged from the discharge port 22 to the flow path 30.

  Further, a gas-liquid separator 31 is disposed on the upper part of the casing 10 and on the opposite side of the pump 19 (see FIG. 1). The gas-liquid separator 31 is composed of a vertical cyclone 32 having an open lower end, and the cyclone 32 extends downward from the upper introduction portion 32a and toward the lower end opening. It is provided with a truncated conical barrel portion 32b and a conical ceiling portion 32c covering the upper side of the introduction portion 32a. The body portion 32b of the cyclone 32 is formed such that a portion corresponding to a substantially half length on the lower side protrudes into a filter chamber 40 described later, and a slit 33 extending in the vertical direction is formed on the peripheral wall of the protruding portion 34a. Is formed.

  In the upper part of the cyclone 32, an opening 30a constituting one end of the flow path 30 is formed. The opening 30a is formed so as to allow the fluid from the pump 19 to flow out in the tangential direction of the cyclone 32, and is provided vertically so as to straddle the introduction portion 32a and the ceiling portion 32c. A plug member 34 having a through hole 34 a is fitted in the center of the ceiling portion 32 c of the cyclone 32. The through hole 34 a of the plug member 34 communicates with a gas separation chamber 60 described later via a discharge channel 36 in a lid 35 attached to the casing 10.

  In the gas-liquid separator 31, the liquid mixed with gas, which has been pumped from the pump 19 through the flow path 30, flows into the cyclone 32 from the opening 30 a to cause a swiveling motion, and the centrifugal action acting between the liquid and the gas. Due to the different forces, the liquid collects radially outward and the gas collects radially inward. The separated liquid flows down from the lower end opening of the body portion 32b to the filter chamber 40. On the other hand, the gas-enriched liquid containing gas passes through the through-hole 34a of the plug member 34 of the ceiling portion 32c. It passes through the discharge channel 36 and is discharged into the gas separation chamber 60.

  As shown in FIG. 5, a filter 41 is disposed in the filter chamber 40. The front end of the filter 41 is fitted in a hole 42 a provided in a vertical partition wall 42 in the casing 10 that defines the filter chamber 40. A compression spring 44 having one end abutted against a lid body 43 covered with the casing 10 is disposed behind the filter 41, and the filter 41 is pressed against the vertical partition wall 42 by the compression spring 44. The opening 10b of the casing 10 closed by the lid body 43 has a sufficient size to allow the filter 41 to be taken in and out, so that the filter 41 can be appropriately replaced by removing the lid body 43. It becomes like this.

  As shown in FIGS. 4 and 6, in front of the filter 41, one end of a flow path 46 leading to an outlet side check valve 45 provided on the upper side of the casing 10 and two suction side check valves 15 are provided. One end of a flow path 47 communicating with the flow path 17 on the next side is disposed with a vertical partition wall 48 interposed therebetween. The outlet side check valve 45 includes a valve seat 51 fitted in a through hole 50 formed in the horizontal partition wall 49 of the casing 10, a valve body 52 with a shaft that is attached to and detached from the valve seat 51, and a lid body 53 of the casing 10. And a valve spring 54 that normally urges the valve body 52 in the closing direction by contacting one end of the valve body 52, and the spring force of the valve spring 54 is set to a weak spring force in order to reduce the flow resistance. The valve body 52 closes when the pump 19 is stopped.

  The secondary side of the outlet side check valve 45 is connected to the outlet 12 via a flow path 55. Accordingly, the liquid separated by the gas-liquid separator 31 and flowing down into the filter chamber 40 opens the outlet side check valve 45 from the filter 41 through the flow path 46 and further passes through the outlet 12 from the flow path 55 to the outside. It is pumped to a device (for example, a flow meter) and only allows the flow of oil in the direction leading to the outlet 12.

  Thus, the vertical partition wall 48 is fitted with a relief valve 56 (see FIG. 5) bolted to the side wall of the casing 10, and the external device is now closed or squeezed while the pump 19 is driven. If this happens, the relief valve 56 is opened, and the liquid is returned from the flow path 47 and the flow path 17 to the suction port 21 of the pump 19. The filter chamber 40 and the flow path 46 form a fluid flow path.

  FIG. 7 is a longitudinal sectional view showing the mounting structure of the relief valve 38. As shown in FIG. 7, a through hole 61 is formed in the upper wall of the casing 10 forming the gas separation chamber 60 so as to face the flow path 36 from the gas-liquid separator 31. A pipe member 62 for supplying the gas-enriched liquid separated by the gas-liquid separator 31 to the gas separation chamber 60 is press-fitted. The lower end of the tube member 62 extends to the inside of a small-volume liquid reservoir 64 provided near the lowest liquid level in the gas separation chamber 60. The liquid reservoir 64 is formed in a U-shaped groove shape from a vertical partition wall 63 of the casing 10, a step portion 63a of the partition wall, and a vertical wall 64a parallel to the partition wall 63, and one end thereof is opened as shown in FIG. Yes. As a result, the gas-enriched liquid supplied into the gas separation chamber 60 through the pipe member 62 once accumulates in the liquid reservoir 64 and then flows and accumulates from one end to the bottom side of the gas separation chamber 60. During this time, the gas is separated from the gas-enriched liquid, and this gas is discharged to the outside from the exhaust port 130 provided on the upper wall of the casing 10.

  A relief valve 38 that opens and closes the discharge channel 36 is provided in the lid 35. The relief valve 38 receives the pressure supplied to the discharge flow path 36, slides in the discharge flow path 36 and moves to the valve open position, and thereby connects the discharge flow path 36 and the gas-liquid separation device 31. It has a body 100 and a coil spring (biasing member) 102 for returning the valve body 100 to the valve closing position.

  FIG. 8 is a perspective view showing a valve body of the relief valve 38. As shown in FIG. 8, the valve body 100 is a spool valve that is slidably inserted in the axial direction into a discharge channel 36 formed in a cylindrical shape, and has an inlet 110 that communicates with the through hole 34a. A cylindrical valve portion 100a that opens and closes, a guide portion 100b that guides sliding in the discharge flow path 36, a shaft portion 100c that connects the shaft centers between the cylindrical valve portion 100a and the guide portion 100b, and a shaft portion 100c It has a groove 100d formed on the outer periphery and a through hole 100e penetrating the center of the shaft center in the axial direction. In addition, a coil spring 102 is fitted into a recess 100f formed on the end surface of the guide portion 100b, and urges the valve body 100 in the valve opening direction (Xb direction in FIG. 7).

  FIG. 9 is an enlarged longitudinal sectional view showing the valve closing operation of the relief valve 38. As shown in FIG. 9, the lid 35 includes an inflow port 110 communicating with the through hole 34 a, a passage 112 branched from the inflow port 110 and extending in the Xb direction, and a pressure communicated with the passage 112. The chamber 114 has a side lid 116 that closes the pressure chamber 114. The pressure chamber 114 is formed integrally with the discharge passage 36, and the cylindrical valve portion 100a of the valve body 100 is slidably fitted therein. Further, a retaining ring 117 as a stopper in the Xb direction with respect to the valve body 100 is engaged with the inner wall of the pressure chamber 114.

  Further, the lid 35 is provided with an outlet 120 that communicates with the inner periphery at an intermediate position in the X direction of the discharge passage 36, and a discharge port 124 that communicates with the other end of the bypass passage 122 and the axis of the discharge passage 36. It has been. The upper lid 118 fixed to the upper part of the lid body 35 is provided with a bypass passage 122 having one end communicating with the outlet 120 and the other end extending in the Xa direction and formed in parallel with the discharge passage 36. It has been. Further, the lid body 35 is provided with a through hole 61 that communicates with the bypass passage 122 and the discharge port 124 and extends in the vertical direction. The lower end of the through hole 61 communicates with the upper end of the pipe member 62. ing. The bypass passage 122 and the discharge port 124 communicate with the gas separation chamber 60 through the through hole 61 and the pipe member 62.

  Here, the opening / closing operation | movement of the valve body 100 is demonstrated. The valve body 100 is fitted in the discharge passage 36 so as to move to a valve opening position or a valve closing position by moving to a position where the hydraulic pressure in the pressure chamber 114 and the biasing force of the coil spring 102 are balanced.

That is, in the pressure chamber 114, the force F1 acts on the end face of the cylindrical valve portion 100a of the valve body 100, and the spring force F2 acts on the concave portion 100f of the valve body 100.
F1 = (P1-P2) × S (1)
In the above equation (1), P1 is the pressure in the pressure chamber 114, P2 is the pressure in the recess 100f, and S is the cross-sectional area of the valve body 100 (the flow-path cross-sectional area of the discharge flow path 36).
F2 = K · Δx (2)
In the above equation (2), K is a spring constant of the coil spring 102 and Δx is a displacement amount of the coil spring 102. Therefore, when the pressure P1 in the pressure chamber 114 rises to the hydraulic pressure from the upper part of the cyclone 32, F1> F2 is established, and the valve body 100 moves in the Xa direction to be closed. Further, when the gas-enriched liquid is supplied to the pressure chamber 114 from the upper part of the cyclone 32, the pressure P1 is reduced, so that F1 <F2 and the valve body 100 moves in the Xb direction to open the valve. .

  As shown in FIG. 9, when hydraulic pressure is applied to the pressure chamber 114, the valve body 100 slides in the Xa direction and is pressed to the valve closing position, and the cylindrical valve portion 100 a is connected to the inlet 110. And the outlet 120 is shut off. At this time, the fluid supplied to the pressure chamber 114 passes through the through hole 100 e of the valve body 100 and is discharged from the discharge port 124 to the through hole 61. Therefore, the through hole 100e functions as a throttle, and the fluid (liquid and bubbles) in the pressure chamber 114 passes through the through hole 61 and the pipe member 62 little by little and is discharged to the gas separation chamber 60.

  FIG. 10 is a longitudinal sectional view showing the relief valve 38 in a closed state. FIG. 11 is an enlarged longitudinal sectional view showing the valve closing operation of the relief valve 38. As shown in FIGS. 10 and 11, when the gas-enriched liquid accumulates in the upper part of the cyclone 32, the pressure is reduced in the pressure chamber 114 by the bubbles, and the valve body 100 slides in the Xb direction by the spring force of the coil spring 102. To do. When the valve body 100 returns to the valve opening position, the cylindrical valve portion 100 a passes through the inlet 110 and the outlet 120, and the groove 100 d of the valve body 100 communicates with the inlet 110 and the outlet 120. Therefore, the gas-enriched liquid accumulated in the inlet 110 is pushed up by the hydraulic pressure from the cyclone 32 and passes through the outlet 120, the bypass passage 122, the through hole 61 and the pipe member 62 from the groove 100 d of the valve body 100. It is discharged to the gas separation chamber 60.

  In addition, the gas-enriched liquid supplied to the pressure chamber 114 passes through the through hole 100 e of the valve body 100 by the liquid pressure from the cyclone 32 and is discharged from the discharge port 124 to the through hole 61. When the gas-enriched liquid accumulated in the upper part of the cyclone 32 is discharged to the gas separation chamber 60, the pressure in the pressure chamber 114 rises again, and the hydraulic pressure from the cyclone 32 acts. It slides in the Xa direction to reach the valve closing position, and the cylindrical valve portion 100a blocks the inlet 110 and the outlet 120. As described above, the valve body 100 moves to the valve opening position or the valve closing position by the pressure (hydraulic pressure or bubble pressure) supplied to the pressure chamber 114 and reliably moves between the inlet 110 and the outlet 120. The gas enrichment liquid accumulated on the upper part of the cyclone 32 can be appropriately discharged into the gas separation chamber 60. The gas separated from the liquid in the gas separation chamber 60 is exhausted to the outside through an exhaust port 130 provided in the upper part of the casing 10.

  Therefore, in the pump unit of this embodiment, the relief valve 38 can be opened and closed by the pressure supplied to the pressure chamber 114, so that the float valve sticks to the valve seat or prevents sticking as in the past. Therefore, it is possible to solve the problem of increasing the size of the float.

  Here, a configuration for returning the liquid accumulated in the gas separation chamber 60 to the suction port 21 of the pump 19 will be described. As shown in FIGS. 2 and 3, a float 67 is disposed on the bottom side of the gas separation chamber 60. The float 67 is pivotable in the vertical direction by axially attaching a tip end portion of a shaft portion 67 a extending from one surface thereof to a lid body 68 bolted to the casing 10. The lid body 68 is provided with a first boss portion 69 projecting from the front and back surfaces thereof, and a shaft hole 70 is formed in the first boss portion 69.

  In addition, an opening 71 is formed at the tip of the boss 69 located in the gas separation chamber 60 so that the shaft hole 70 communicates with the gas separation chamber 60. The opening 71 is configured as a valve seat for the return valve 72, and a valve body (poppet valve) 74 attached to the shaft portion 67 a of the float 67 is fitted into the opening 71. The return valve 72 moves the valve body 74 upward in response to the rise of the float 67 and opens the opening 71.

  The float 67 and the valve body 74 are integrated with the lid body 68 in advance, and can be taken in and out of the gas separation chamber 60 through the opening 10 c of the casing 10 closed by the lid body 68. . A plug 75 that closes the shaft hole 70 is screwed to one end of the first boss 69 on the outside of the lid 68.

  On the other hand, as shown in FIGS. 4 and 5, a return flow path 76 that communicates from the side surface of the casing 10 to the secondary flow path 47 of the relief valve 56 is formed in the lower part of the casing 10. The return channel 76 and the shaft hole 70 in the first boss 69 are connected by a communication hole (not shown) in the second boss 77 provided in the casing 10. A check valve (flapper valve) 78 that restricts the backflow of the liquid into the shaft hole 70 in the first boss portion 69 is provided. As a result, when the liquid accumulates in the gas separation chamber 60 and the float 67 rises, the return valve 72 opens and the liquid in the gas separation chamber 60 flows into the shaft hole 70 and the second boss portion in the first boss portion 69. 77 is returned to the suction port 21 of the pump 19 via the communication hole in 77, the return flow path 76, the secondary flow path 47 of the relief valve 56, and the secondary flow path 17 of the suction check valve 15. It becomes like this.

  In the valve assembly 16, the valve body is opened by the generation of negative pressure in the pump 19, and the fluid flowing in from the strainer 14 flows into the flow path 17 that leads to the suction port 21 of the pump 19.

  On the other hand, the relief valve 56 disposed in front of the filter 41 opens the valve body when the liquid pressure in the flow path 46 increases more than necessary, and the liquid in the flow path 46 causes the flow paths 47 and 17 to flow. To the suction port 21 of the pump 19.

  Hereinafter, the operation of the pump unit configured as described above will be described. When the rotor 23 of the pump 19 is rotationally driven by a motor (not shown), the suction side check valve 15 opens, and the fluid in the tank passes from the inlet 11 through the strainer 14, the suction side check valve 15 and the flow path 17. Is sucked into the pump 19 and discharged from the discharge port 22 to the flow path 30. Then, the fluid discharged from the pump 19 flows toward the gas-liquid separator 31 and flows into the cyclone 32 from the opening 30a of the flow path 30 to cause a swirling motion. As it collects, gas collects inward in the radius.

  In the present embodiment, since the vertical cyclone 32 is used as the gas-liquid separator 31 in particular, the liquid and the gas are separated in the vertical direction due to the difference in specific gravity, and the gas-liquid separation ability is improved in combination with the centrifugal separation. Further, since the body portion 32b of the cyclone 32 is gradually narrowed toward the lower end opening, the flow velocity of the swirling flow increases as it goes downward, and the gas-liquid separation capability is further improved. Further, since the ceiling portion 32c of the cyclone 32 is formed in a conical shape, not only is it easy to create a downward swirling flow, but also the flow velocity of the swirling flow is increased at the initial stage when the fluid flows into the cyclone 32, and gas-liquid separation is performed. The ability is further improved.

  The liquid thus separated flows down from the lower end opening of the body portion 32b to the filter chamber 40, while the gas-enriched liquid containing gas is introduced into the lid 35 from the through hole 34a of the plug member 34 of the ceiling portion 32c. To the inlet 110 and the pressure chamber 114.

  At this time, since the ceiling portion 32c of the cyclone 32 has a conical shape, the gas-enriched liquid can be easily discharged. The gas-enriched liquid supplied into the pressure chamber 114 reduces the hydraulic pressure that presses the valve body 100 of the relief valve 38 in the valve closing direction, so that the valve body 100 is driven by the spring force of the coil spring 102. Slide to the open position. As a result, since the groove 100d of the valve body 100 communicates between the inlet 110 and the outlet 120, the gas-enriched liquid accumulated in the inlet 110 is pushed up by the hydraulic pressure from the cyclone 32 and the valve body 100. From the groove 100d, the gas passes through the outlet 120, the bypass passage 122, the through hole 61 and the pipe member 62 and is discharged to the gas separation chamber 60.

  The liquid flowing down into the filter chamber 40 passes through the filter 41 and is pushed out into the flow path 46, and the outlet check valve 45 is opened by the pressure of the liquid to be pumped from the flow path 55 to the outlet 12. Here, when a slight amount of gas remains in the liquid separated by the gas-liquid separator 31, the gas is accumulated in the upper part of the filter chamber 40. The accumulated gas remains in the upper part of the filter chamber 40 because the liquid flows during the operation of the pump 19. However, when the pump 19 is stopped, the gas is accumulated in the cyclone 32 from the slit 33 of the trunk portion 32 b. Returning to FIG. 2, the pump 19 is discharged from the ceiling 32c in response to the re-operation. Therefore, the liquid containing gas is not supplied to the outflow port 12. As described above, when the outflow of the liquid from the outflow port 12 is stopped or throttled, the relief valve 56 is opened and the liquid is returned to the suction port 21 of the pump 19.

  On the other hand, the gas-enriched liquid discharged from the cyclone 32 by the opening operation of the relief valve 38 in the lid 35 is supplied into the gas separation chamber 60 through the pipe member 62. At this time, if the gas-enriched liquid rapidly falls freely into the gas separation chamber 60, the liquid in the gas separation chamber 60 is greatly agitated to cause foaming, the float 67, that is, the return valve 72 malfunctions, and the return flow path. A liquid containing gas flows into 76. However, in this embodiment, since the tip of the tube member 62 is positioned in the liquid in the liquid reservoir 64, the stored liquid in the gas separation chamber 60 is not greatly agitated by the gas-enriched liquid. Liquid foaming and its diffusion are suppressed. Gas separation proceeds in the gas separation chamber 60, and the separated gas is discharged from the air vent 65 of the casing 10 to the outside. In this way, the liquid from which the gas has been separated accumulates in the gas separation chamber 60, and the liquid level is gradually raised. Then, the float 67 rises, the valve body 74 of the return valve 72 opens, the liquid in the gas separation chamber 60 flows into the return flow path 76, and the secondary flow path 47 of the relief valve 56, the suction side check. It is returned to the suction port 21 of the pump 19 via the flow path 17 on the secondary side of the valve 15.

  Thus, for example, when a large amount of air (including liquid) is sucked into the casing 10 due to a problem on the tank side, the pressure chamber 114 is depressurized from the liquid pressure and the relief valve 38 is opened. As a result, the air is quickly discharged to the chamber 60, so that no air leaks to the outlet 12.

  FIG. 12 is a longitudinal sectional view showing the configuration of the second embodiment. In the description of the second embodiment, the same parts as those in the first embodiment are denoted by the same reference numerals and the description thereof is omitted.

  As shown in FIG. 12, a relief valve 138 that opens and closes the discharge flow path 36 is provided in the lid 35. The relief valve 138 receives the pressure supplied to the discharge flow path 36, slides in the discharge flow path 36, and moves to the valve open position, thereby communicating the discharge flow path 36 and the gas-liquid separation device 31. It has a body 200 and a coil spring (biasing member) 102 for returning the valve body 200 to the valve closing position.

  FIG. 13 is a perspective view showing the valve body of the second embodiment. As shown in FIG. 13, the valve body 200 is a spool valve that is slidably inserted in the axial direction into a discharge channel 36 formed in a cylindrical shape, and has an inlet 110 that communicates with the through hole 34a. A cylindrical valve portion 200a that opens and closes, a guide portion 200b that is divided into four so as to guide sliding in the discharge flow path 36, and a shaft portion 200c that connects the shaft centers between the cylindrical valve portion 200a and the guide portion 200b. And a groove 200d formed on the outer periphery of the shaft portion 100c and a through hole 200e penetrating the center of the shaft center in the axial direction. In addition, a coil spring 102 is fitted into a recess 200f formed on the end face of the guide portion 200b, and the valve body 200 is urged in the valve opening direction (Xb direction in FIG. 12). Furthermore, the four guide portions 200b are formed to protrude in the circumferential direction at intervals of 90 degrees, and a notch 200g that communicates the groove 200d and the recess 200f is opened between the guide portions 200b.

  FIG. 14 is an enlarged longitudinal sectional view showing the valve closing operation of the relief valve 138. As shown in FIG. 14, the lid 35 is in communication with the inflow port 110 communicating with the through hole 34 a, the passage 112 branched from the inflow port 110 and extending in the Xb direction, and the passage 112. A pressure chamber 114 and a side lid 116 that closes the pressure chamber 114 are provided. The pressure chamber 114 is formed integrally with the discharge passage 36, and the cylindrical valve portion 100a of the valve body 100 is slidably fitted therein.

  Further, the lid 35 is not provided with the outlet 120 and the bypass passage 122 as in the first embodiment, and the discharge port 124 communicating with the axial center of the discharge flow path 36 communicates with the through hole 61. Is provided. The discharge port 124 communicates with the gas separation chamber 60 through the through hole 61 and the pipe member 62.

  In the second embodiment, the inner diameter of the discharge channel 36 is smaller than the inner diameter of the pressure chamber 114, and a step 202 is provided at the boundary between the discharge channel 36 and the pressure chamber 114. The step portion 202 serves as a stopper in the Xa direction with respect to the cylindrical valve portion 200a.

  Here, the opening / closing operation | movement of the valve body 200 is demonstrated. The valve body 200 is fitted in the discharge flow path 36 so as to move to a valve opening position or a valve closing position by moving to a position where the pressure of the pressure chamber 114 and the biasing force of the coil spring 102 are balanced.

  As shown in FIG. 14, when hydraulic pressure is applied to the pressure chamber 114, the valve body 200 slides in the Xa direction and is pressed to the valve closing position, and the cylindrical valve portion 100 a is connected to the inlet 110. Is shut off. At this time, the fluid supplied to the pressure chamber 114 passes through the through hole 200 e of the valve body 200 and is discharged from the discharge port 124 to the through hole 61. Therefore, the through hole 200e functions as a throttle, and the fluid in the pressure chamber 114 is discharged to the gas separation chamber 60 through the through hole 61 and the pipe member 62 little by little.

  FIG. 15 is a longitudinal sectional view showing a state in which the relief valve 138 is closed. FIG. 16 is an enlarged longitudinal sectional view showing the valve closing operation of the relief valve 138. As shown in FIGS. 15 and 16, when the gas-enriched liquid accumulates in the upper part of the cyclone 32, the pressure in the pressure chamber 114 is reduced by bubbles, so that the valve body 200 is moved in the Xb direction by the spring force of the coil spring 102. It slides and returns to the valve opening position, the cylindrical valve part 200a passes through the inflow port 110, and the groove 200d of the valve body 200 moves to a position facing the inflow port 110. Therefore, the inlet 110 and the outlet 124 are communicated with each other through the groove 200d and the notch 200g of the valve body 200. As a result, the gas-enriched liquid accumulated in the inlet 110 is pushed up to the hydraulic pressure from the cyclone 32 and passes through the outlet 200, the through hole 61 and the pipe member 62 from the groove 200d and the notch 200g of the valve body 200. It is discharged to the gas separation chamber 60.

  Further, the gas-enriched liquid supplied to the pressure chamber 114 passes through the through hole 200 e of the valve body 200 by the liquid pressure from the cyclone 32 and is discharged from the discharge port 124 to the through hole 61. When the gas-enriched liquid accumulated in the upper part of the cyclone 32 is discharged to the gas separation chamber 60, the hydraulic pressure from the cyclone 32 acts on the pressure chamber 114 again, so that the valve body 200 slides in the Xa direction. Then, it reaches the valve closing position, and the cylindrical valve portion 200a blocks the inflow port 110 and the outflow port 120. As described above, the valve body 200 moves to the valve opening position or the valve closing position by the pressure (hydraulic pressure or pressure of the gas-enriched liquid) supplied to the pressure chamber 114 to ensure that the inlet 110 and the outlet 124 The gas-enriched liquid accumulated in the upper part of the cyclone 32 can be discharged to the gas separation chamber 60 as appropriate.

  In the above-described embodiment, the pump unit mounted on the oil supply device is taken as an example. However, the present invention is not limited to this, and the present invention can also be applied to other devices having a liquid supply path in which bubbles are mixed in the liquid. Of course.

  Further, in the above embodiment, the pump unit is arranged in the system path for supplying the oil liquid, but the present invention can be applied to the case where the pump unit is arranged in the system path for supplying liquid other than the oil liquid. is there.

It is a longitudinal cross-sectional view which shows one Example of the pump unit by this invention. It shows the structure of the present pump unit and is a cross-sectional view taken along the line II-II in FIG. It is sectional drawing which follows the III-III arrow line of FIG. It is sectional drawing which follows the IV-IV arrow line of FIG. It is sectional drawing which follows the VV arrow line of FIG. It is a side view which shows this pump unit as a partial cross section. It is a longitudinal cross-sectional view which shows the attachment structure of the relief valve. 3 is a perspective view showing a valve body of a relief valve 38. FIG. 3 is an enlarged longitudinal sectional view showing a valve closing operation of the relief valve 38. FIG. FIG. 4 is a longitudinal sectional view showing a state where the relief valve 38 is closed. 3 is an enlarged longitudinal sectional view showing a valve closing operation of the relief valve 38. FIG. 5 is a longitudinal sectional view showing the configuration of Example 2. FIG. It is a perspective view which shows the valve body of Example 2. FIG. It is a longitudinal cross-sectional view which expands and shows the valve closing operation | movement of the relief valve 138. FIG. It is a longitudinal cross-sectional view which shows the valve closing state of the relief valve 138. FIG. It is a longitudinal cross-sectional view which expands and shows the valve closing operation | movement of the relief valve 138. FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Casing 11 Inlet 12 Outlet 19 Pump 21 Pump suction port 22 Pump discharge port 31 Gas-liquid separator 32 Cyclone 35 Lid 36 Discharge flow path 38,138 Relief valve 40 Filter chamber 41 Filter 60 Gas separation chamber 61 Through Hole 62 Tube member 100, 200 Valve body 102 Coil spring (biasing member)
110 Inlet 112 Passage 114 Pressure chamber 120 Outlet 122 Bypass passage 124 Exhaust

Claims (3)

A pump for sucking fluid from the inlet into a casing having an inlet and an outlet;
A gas-liquid separator that separates the fluid discharged from the pump into a liquid and a gas-enriched liquid;
A gas separation chamber for separating gas from the gas-enriched liquid separated by the gas-liquid separator;
A flow path for sending a gas-enriched liquid from the gas-liquid separator to the gas separation chamber;
A relief valve that opens the flow path in response to a pressure drop of the gas-enriched liquid from the gas-liquid separator,
In the pump unit that guides the liquid separated by the gas-liquid separator to the outlet and discharges the gas separated in the gas separation chamber to the outside of the casing by opening the relief valve,
The relief valve is
A valve body that receives the pressure supplied to the flow path and slides in the flow path to move to the valve-closed position so as to communicate the flow path and the gas-liquid separation device;
An urging member for returning the valve body to a valve open position;
A pump unit comprising:   2. The pump unit according to claim 1, wherein the valve body is a spool having a groove formed on an outer periphery thereof to communicate the flow path and the gas-liquid separator.   2. The pump unit according to claim 1, wherein the valve body has a through hole for supplying a gas-enriched liquid from the gas-liquid separator to the gas separation chamber.

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