JP2012092727A - Vortex pump - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a vortex pump that improves gas exhaust performance to reduce restrictions on pump posture during self-priming and to prevent a gas from staying in a pump chamber.SOLUTION: The vortex pump includes: a vane 18 pressurizing fluid by rotation: an impeller 4 having the vane 18 on an outer periphery; the pump chamber 1 storing the impeller 4 therein; and a motor rotating the impeller 4. The pump further has a channel 5 where the fluid flows, on an outer periphery side of the vane 18. The pump chamber 1 includes: a suction pipe 21 communicating with an upstream end 6 of the channel 5; an discharge pipe 22 communication with a downstream end 7 of the channel 5; and a gas-liquid separation part for separating the fluid into gas and liquid at the downstream end 7. A casing forming the pump chamber 1 has a surface facing the impeller 4, and the discharge pipe 22 is opened on the facing surface. In addition, a protrusion 27 circumferentially having a plane is disposed on a portion forming the downstream end 7 of the channel 5 on the facing surface, and the plane serves as a collision surface 44 of the gas-liquid separation part.

Description

  The present invention relates to a vortex pump, and more particularly to a self-priming vortex pump having a flow path through which fluid flows on the outer periphery of an impeller.

  Conventionally, an eddy current pump including an impeller that pressurizes a liquid, a pump chamber that houses the impeller, a motor that rotates the impeller, and a flow path that flows along the outer periphery of the impeller. There is. Such a vortex pump is used for a liquid fuel supply device of an automobile and the like in order to send liquid stored in an external tank or the like outside the pump in a pressurized state.

  In recent years, the eddy current pump is sometimes used as a power source (circulation pump) for supplying a refrigerant in a cooling means for cooling a heat generating device such as a computer because of its high pressurization capacity.

JP 2003-232289 A

  However, since the conventional vortex pump does not have a very high gas discharge performance, it is necessary to provide a tank above the vortex pump and assist gas discharge by the weight of fluid in the tank when performing the self-priming operation. For this reason, when installing a conventional vortex pump on a structure or the like, the position of the pump such as the positional relationship with the tank (fluid supply source) and the direction of the pump is limited, and devices and equipment used in various positions There is a problem that it is difficult to install (install).

  In addition, if gas enters the flow path together with the liquid when the liquid flows in, the liquid gathers on the outer periphery of the impeller due to the centrifugal force accompanying the rotation of the impeller, and the gas having a density lower than that of the liquid moves toward the rotation center of the impeller. get together. For this reason, the gas is difficult to be discharged from the discharge pipe and may remain as a bubble around the shaft. If the bubble (gas) stays around the shaft, an abnormal stop such as pump lock or shaft sticking may occur when the pump is driven. Sometimes.

  Therefore, in view of this situation, the gas discharge performance (self-priming performance) at the time of gas-liquid mixed fluid inhalation or self-priming operation is improved to reduce the restriction of the pump posture of the self-priming operation, and the gas in the pump chamber An object of the present invention is to provide a vortex pump that suppresses stagnation.

  In order to solve the above problems, the vortex pump of the present invention includes a blade portion that pressurizes a fluid by rotation, an impeller having a blade portion on an outer periphery, a pump chamber that houses the impeller inside, and the blade A motor that rotates the vehicle, and has a flow path through which the fluid flows on an outer peripheral side of the impeller of the pump chamber, and the pump chamber communicates with an upstream end of the flow path; A discharge pipe communicating with the downstream end of the flow path, and a gas-liquid separation unit that performs gas-liquid separation of the fluid at the downstream end of the flow path, and a casing forming the pump chamber includes the impeller and the An opposed surface facing the axial direction of the rotating shaft core of the impeller, and the inside of the discharge pipe communicates with the pump chamber from the opposed surface along the axial direction to form the downstream end of the opposed surface Protrusions with a flat surface in the circumferential direction are provided at Characterized in that the said plane collide the fluid in the gas-liquid separator is obtained by the impact surface to perform gas-liquid separation.

  As this vortex pump, it is preferable that the gas-liquid separation part has a flat surface aligned with the inner surface of the discharge pipe along the axial direction.

  The vortex pump preferably has a rectangular cross-sectional shape obtained by cutting the inside of the discharge pipe perpendicular to the fluid flow direction.

  As the vortex pump, the pump chamber has a partition portion that partitions the downstream end and the upstream end of the flow path, and the partition portion has a side wall on the downstream end side that is flush with the inner surface of the discharge pipe. It is preferable that

  The vortex pump is preferably provided with a reflux path for refluxing gas at the upstream end, and the upstream end of the reflux path is provided in the middle of the flow path or downstream from the middle.

  By adopting such a configuration, the gas discharge performance at the time of gas-liquid mixed fluid inhalation or self-priming operation can be improved and the restriction on the pump posture of self-priming operation can be relaxed compared to the conventional one. In addition, it is possible to suppress the retention of gas in the pump chamber.

It is sectional drawing cut | disconnected on the rotation circle of the eddy current pump of an example of embodiment. It is a perspective view of an external appearance same as the above. It is the perspective view of the (a) external appearance and (b) flow-path downstream end periphery which cut | disconnected a part with the AA line same as the above. It is sectional drawing cut | disconnected in the axial direction same as the above. It is sectional drawing to which the blade part periphery of FIG. 4 was expanded. It is sectional drawing of a downstream end same as the above. It is sectional drawing cut | disconnected on the rotation circle of the eddy current pump of another example of embodiment. It is a perspective view of the appearance which permeate | transmitted the pump case same as the above. It is sectional drawing cut | disconnected in the axial direction same as the above. It is explanatory drawing of the installation position change of the reflux path upstream end in the same as the above. It is a figure of the fluid analysis result of the pressure fluctuation accompanying the difference in an installation position same as the above.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

  As shown in FIG. 4, the vortex pump according to the embodiment includes a motor that is a driving source, an impeller 4 that is rotationally driven by the motor, and a flow in which fluid flows inside the impeller 4. Road 5 is provided. The impeller 4 has a blade portion 18 that pressurizes and flows a fluid on the outer peripheral side, and has a plurality of magnetic poles integral with the rotor 14 on the inner peripheral side of the impeller 18. The side is a flow path 5.

  Specifically, as shown in FIGS. 2 to 4, the vortex pump includes a pump chamber 1 having a flow path 5 and accommodating the impeller 4, and a motor unit 2 partitioned from the pump chamber 1. The pump chamber 1 is surrounded by a pump case 20 that forms an outer shell of the pump chamber 1 and a separation plate 31 that partitions the pump chamber 1 and the motor unit 2.

  The motor also includes an annular stator 8 having a coil, a control unit 9 that controls driving of the motor, a cylindrical rotor 14 having a plurality of magnets (magnetic poles), and a rotation that rotatably supports the rotor 14. And a support part. The stator 8 and the control unit 9 are arranged in the motor unit 2, and the rotor 14 and the rotation support unit are arranged in the pump chamber 1.

  And the control part 9 controls the motor drive by controlling the electric current which flows into the coil of the stator 8, and the stator 8 is carrying out the energization control of the control part 9, and makes the rotor 14 magnetically rotate. Further, the control unit 9 and the stator 8 are fixed to the separation plate 31 via a molding material 10 filled in the motor unit 2, and the molding material 10 has an outer shell of the motor unit 2 as shown in FIG. 2. Is forming.

  On the other hand, as shown in FIG. 4, the rotor 14 and the rotation support portion are arranged substantially concentrically with the stator 8 and arranged on the inner periphery of the stator 8, and the rotor 14 and the stator 8 have a separation plate 31 interposed therebetween. The rotation support portion is disposed on the inner periphery of the rotor 14.

  The rotation support portion includes a shaft 11 positioned at the rotation center of the rotor 14, a bearing portion 12 that is rotatably mounted around the shaft 11, and a receiving plate 13 that positions the bearing portion 12 on the shaft 11. And have. The shaft 11 has one end fixed to the separation plate 31 and the other end fixed to the pump case 20, and the bearing portion 12 has a rotor 14 integrally attached to the outer periphery. Rotate to.

  Hereinafter, unless otherwise specified, the axial direction of the shaft 11 is simply referred to as an axial direction, and the radial direction of the shaft 11 is simply referred to as a radial direction. The shape viewed in the axial direction is described as a shape in plan view, and the rotation circle of the impeller 4 in plan view is simply referred to as a rotation circle.

  The receiving plates 13 are disposed at both ends of the bearing portion 12 in the axial direction, and are not rotatable with respect to the shaft 11 and are fixed to the shaft 11, the separation plate 31, and the pump case 20. Therefore, the bearing portion 12 and the rotor 14 are defined at predetermined positions in the axial direction with respect to the shaft 11, and the rotor 14 becomes difficult to move in the axial direction due to vibration during rotation and the like. Yes. Further, the receiving plate 13 prevents the bearing portion 12 from coming into direct contact with the casing, prevents the casing from being worn when the rotor 14 rotates, and suppresses the occurrence of misalignment due to deterioration over time.

  The rotor 14 has a cylindrical shape in which a plurality of magnets are arranged in the circumferential direction. The rotor 14 has a projecting portion 15 projecting toward the axial center side in the middle of the axial dimension of the inner circumferential surface of the cylinder, and the rotor 14 is fixed to the bearing portion 12 via the projecting portion 15. ing. Further, the rotor 14 is provided with an annular disk 16 substantially concentrically and integrally provided at one end in the axial direction of the cylinder, and the rotor 14 rotates with the bearing portion 12 to rotate the disk 16. It has become.

  As shown in FIGS. 1 and 4, the disk 16 has a blade portion 18 at the outer peripheral end of the disk 16, and the inner diameter is substantially the same as the inner diameter of the cylinder of the rotor 14. The diameter is larger than the cylindrical outer diameter of the rotor 14. The impeller 4 is obtained by integrating the disc 16 and the rotor 14.

  And the blade | wing part 18 of the disc 16 consists of the some notch 19 notched in the circumferential direction at substantially equal intervals. Further, as shown in FIGS. 4 and 5, each notch 19 is notched in a substantially arc shape and substantially the same size and shape when viewed in the radial direction, and a plate surface 17 facing the pump case side of the disc 16. It opens to the outer peripheral side of the side and radial direction.

  The impeller 4 is not limited to the one integrated with the rotor 14, and the impeller 4 (disk 16) and the rotor 14 may be made of different members. In this case, it is preferable to provide a magnet on the inner periphery of the disk 16 to magnetically connect the disk 16 and the rotor 14 and to rotate the disk 16 together with the rotor 14.

  As shown in FIG. 2, the pump chamber 1 includes an intake pipe 21 that sucks liquid into the pump chamber 1 from the outside, and a discharge pipe 22 that discharges liquid from the pump chamber 1 to the outside. It protrudes along. The suction pipe 21 is a cylinder having a substantially rectangular cross section, the opening at one end communicates with a liquid supply source such as an external pipe or a storage tank, and the opening at the other end is a flow path in the pump chamber 1. 5 (details will be described later). On the other hand, the discharge pipe 22 is a cylinder having a substantially rectangular cross section and is substantially the same shape and size as the suction pipe 21, with one end opening communicating with an external pipe or liquid supply object, and the other end opening being a figure. As shown in FIG. 3, it communicates with the downstream end 7 of the flow path 5.

  The inner surface of the pump chamber 1 has an annular inner surface that faces each plate surface 17 of the disk 16 as shown in FIGS. 4 and 5. The flange portion 33 of the separation plate 31 forms a substantially annular facing surface that faces the one plate surface 17 of the disc 16, and the substantially annular facing surface that faces the other plate surface 17 serves as the pump case 20. Both opposing surfaces are located substantially concentric with the shaft 11.

  Specifically, as shown in FIG. 4, the separation plate 31 includes a cylindrical portion 32 having a bottom at one end, an annular flange portion 33 extending from the other end of the cylindrical portion 32 to the outer periphery, and a flange portion 33. And an annular standing wall 35 that rises toward the pump case 20. In the cylindrical portion 32, the stator 8 is positioned substantially concentrically on the outer peripheral side, and the rotor 14 and the shaft 11 are positioned substantially concentric on the inner peripheral side. A fixing portion that fixes one end of the projection protrudes in the axial direction.

  The flange portion 33 includes one end surface 34 facing the one plate surface 17 of the disk 16, and a standing wall 35 protruding in the axial direction from the outer periphery of the one end surface 34, and one end surface which is an opposing surface. 34 has a predetermined clearance between the disk 16 and one plate surface 17 in the axial direction.

  As shown in FIG. 1, the standing wall 35 is a ring that is substantially concentric with the impeller 4 and faces the axial center side, and rises in the axial direction from the outer peripheral side of the one end face 34. Further, as shown in FIG. 5, the standing wall 35 is a partition located between a substantially C-shaped recess 36 that is recessed from the wall surface toward the outer periphery and the circumferential end of the recess 36. Part 37.

  The recess 36 is separated by a dimension larger than the clearance between the peripheral surface and the radial direction of the outer peripheral end of the disk 16, and forms a substantially C-shaped space in plan view on the outer periphery of the blade portion 18.

  As shown in FIG. 4, the recess 36 is positioned so that one end side in the circumferential direction of the C shape is aligned with the suction pipe 21 in the axial direction, and the other end side in the circumferential direction is a discharge pipe as shown in FIG. 3. 22, the partition portion 37 is positioned between the other end and the one end in the rotational direction RD.

  The partition portion 37 has an arc-shaped inner peripheral surface along the circumferential direction, the inner peripheral surface is substantially flush with the wall surface of the standing wall 35, and the wall surface of the standing wall 35 and the partition portion 37 is A predetermined clearance is provided between the outer peripheral end of the disk 16 and the radial direction.

  And the partition part 37 has the side wall 38 in the both ends of the circumferential direction of a circular arc, and the end surface of an axial direction is contact | abutted to the opposing surface of the pump case 20. As shown in FIG. Furthermore, each side wall 38 has a substantially flat surface along the axial direction, and is positioned so as to substantially overlap the C-shaped end of the recess 36 in the axial direction.

  As shown in FIG. 4, the pump case 20 has a fixed circular portion 23 that fixes the other end of the shaft 11, and a flat portion 24 that is positioned on the outer periphery of the fixed circular portion 23 and has a substantially annular flat surface 25 in plan view. The inner surface of the pump chamber 1 is formed.

  In the plane portion 24, the annular plane 25 is a facing surface facing the plate surface 17 (the other plate surface 17) opposite to the plate surface 17 facing the flange portion 33 of the disk 16. The planar portion 24 is formed on the planar surface 25 in a substantially C-shaped concave portion 26 that is recessed in the axial direction, and a projecting portion 27 that is located between the circumferential directions of the concave portion 26 and protrudes in the axial direction. have. Further, the flat surface portion 24 has a predetermined clearance between the flat surface 25 on the inner peripheral side of the recessed portion 26 and the other plate surface 17 in the axial direction.

  The recessed portion 26 has a C-shaped top surface that is substantially concentric with the shaft 11, and the top surface is separated by a dimension larger than the clearance between the other plate surfaces 17 in the axial direction. The space is formed. The recess 26 is positioned so that the outer peripheral end substantially overlaps with the peripheral surface of the recess 36 in plan view, and the peripheral surface of the outer peripheral end is substantially flush with the peripheral surface of the recess 36 in the axial direction. The inner peripheral end is located on the inner peripheral side or substantially overlapping the inner peripheral end of the blade portion 18.

  Further, as shown in FIG. 4, the recessed portion 26 has a suction communication hole 29 communicating with the suction pipe 21 at one end portion in the circumferential direction of the top surface, and the other end portion of the top surface. As shown in FIG. 3, a discharge communication hole 30 communicating with the discharge pipe 22 is opened.

  As shown in FIG. 4, the suction communication hole 29 has a rectangular shape in plan view that is substantially the same shape and the same size as the suction pipe 21, and is open to the top surface. The opening communicates with the inside of the suction pipe 21, and And the inner surface of the suction pipe 21 are substantially flush with each other along the axial direction. As shown in FIG. 3, the discharge communication hole 30 has a rectangular shape in plan view that is substantially the same shape and size as the discharge pipe 22, and is open to the top surface. The opening communicates with the inside of the discharge pipe 22. The edge of the opening and the inner surface of the discharge pipe 22 are substantially flush with each other along the axial direction.

  Further, the recessed portion 26 is positioned so that the circumferential end thereof substantially overlaps the circumferential end of the recessed portion 36 along the axial direction, and communicates with the recessed portion 36 in the axial direction. The space formed by the recess 36 has a substantially L-shaped cross section when viewed in the rotation direction RD. The L-shaped space formed by the recessed portion 26 and the recessed portion 36 is a flow path 5 through which fluid flows.

  Therefore, the end of the concave portion 26 and the recess 36 on the suction pipe 21 side in the circumferential direction of the C-shape is the upstream end 6 side of the flow path 5, and the end on the discharge pipe 22 side is the end of the flow path 5. It is the downstream end 7 side. And since the partition part 37 and the protrusion 27 are located between the downstream end 7 and the upstream end 6 of the flow path 5 along the rotation direction RD, the pressure difference between the upstream side and the downstream side is maintained, and the downstream side The flow of fluid from the side to the upstream side is restricted.

  Further, the flow path 5 communicates with the notch 19 when the impeller 4 rotates, thereby generating a vortex flow in the fluid flow. Specifically, as indicated by an arrow Ar in FIG. 5, the fluid that flows in the rotational direction RD in the flow path 5 flows into the notch 19 while flowing in the flow path 5, and then enters the arc of the notch 19. It flows along and returns to the flow path 5.

  Further, as shown in FIGS. 4 and 6, the protrusion 27 is located between the circumferential directions of both ends of the recess 26, and the end surface facing the axial direction of the protrusion 27 is the recess of the flat portion 24. 26 is substantially flush with the flat surface 25 on the inner peripheral side of the inner wall 26 and is in contact with the end surface of the partition portion 37 facing the axial direction.

  The protrusions 27 are respectively provided with substantially flat side surfaces 28 along the axial direction at both ends in the circumferential direction, and each side surface 28 is substantially flush with the side wall 38 of the partition portion 37 along the axial direction. ing. Therefore, the protrusion 27 substantially closes the space on one end side (the recessed portion 26 side) in the axial direction of the blade portion 18 of the flow path 5, and partitions the flow path 5 together with the partition portion 37 in a C shape in plan view. .

  Further, as shown in FIG. 4, the protrusion 27 has one side surface 28 that is substantially flush with the inner surface of the suction pipe 21 along the axial direction, and the other side surface 28 is connected to the inner surface of FIG. As shown, the inner surface of the discharge pipe 22 is also substantially flush with the axial direction. The other side surface 28 of the protrusion 27 serves as a collision surface 44 of the gas-liquid separation unit where the fluid flowing in the flow path 5 collides, and when the gas-liquid mixed fluid collides with the collision surface 44, After the gas-liquid separation of the fluid, the fluid, the separated gas, and the like are sent to the discharge pipe 22.

  As described above, since the side surface 28 of the protrusion 27 is used as the collision surface 44 of the gas-liquid separation unit, the fluid collides with the substantially flat collision surface 44. Therefore, the collision surface 44 is more fluid than the curved surface. The impact force on the impact surface 44 can be increased. And, by increasing the collision force, the gas-liquid separation efficiency is increased, and it is difficult for the gas to remain in the pump chamber 1, and it is difficult to cause an abnormal stop such as pump lock or shaft sticking due to gas retention around the shaft. Thus, the stability of driving the pump can be improved.

  In addition, by suppressing gas stagnation, the pump gas discharge performance (self-priming performance) during gas-liquid mixed fluid inhalation or self-priming operation can be improved, and the restriction on the pump posture during self-priming operation is eased. It is possible to improve the degree of freedom of the installation posture of the pump.

  Since the restriction on the posture of the pump has been relaxed, the fluid supply device equipped with a vortex pump such as a liquid fuel supply device for vehicles can be reduced in size by reducing dead space and fluid supply compared to conventional devices. The center of gravity can be lowered by changing the position of the source. Furthermore, by relaxing the restriction on the pump posture, even equipment that is used in various postures, such as computers and projectors, can be mounted (installed) as a circulation pump in a fluid circulation device such as a cooling device for the equipment. It becomes possible.

  Further, the partition portion 37 narrows the radial space between the inner surface of the pump chamber 1 and the blade portion 18 at the tip end side (partition portion 37 side) in the rotational direction RD from the downstream end 7 of the flow path 5. 27 narrows the interval between the inner surface of the pump chamber 1 and the blade portion 18 in the axial direction. That is, by providing the partition part 37 and the protrusion 27, the inner surface of the pump chamber 1 around the blade part 18 at the tip side portion compared to the conventional partition part 37 narrowed only in the radial direction, The gap is narrowed.

  Therefore, it becomes difficult for the fluid that has flowed to the downstream end 7 to avoid the collision surface 44, the fluid can easily collide with the collision surface 44, and gas-liquid separation can be easily performed in the gas-liquid separation unit. And since the escape space of the separated gas in the pump chamber 1 is less likely to occur, it becomes difficult for the gas to escape to the upstream side and the shaft core side, and the gas can be easily sent (discharged) to the discharge pipe 22. Emission efficiency can be improved. Hereinafter, the collided liquid, gas-liquid mixed fluid, and separated gas are collectively referred to as fluid.

  Further, since the collision surface 44 is substantially flush with the side wall 38 and the inner surface of the discharge pipe 22 along the axial direction, the fluid or the like flowing to the downstream end 7 can be smoothly smoothed along the substantially flush surface. It can lead out into the discharge pipe 22, and the delivery efficiency of the fluid to the discharge pipe 22 can be improved.

  And by contacting the end face of the partition part 37 and the end face of the projection part 27, the tip side is substantially blocked from the downstream end 7 of the flow path 5 having the L-shaped cross section, and it is possible to make it more difficult for a fluid or the like to escape. The collision surface 44 can be widened. Therefore, the fluid easily collides with the collision surface 44, the gas-liquid separation efficiency is increased, and the gas discharge performance and the self-priming performance can be improved.

  Furthermore, since the distal end side of the downstream end 7 of the flow path 5 is substantially closed, the fluid flows into the discharge pipe 22 as compared with the case where the recessed portion 26 without the projecting portion 27 is annularly recessed (recessed in the entire circumference). It becomes easy to send out, and the delivery efficiency to the discharge pipe 22 of fluid etc. can be improved.

  Reference numeral 39 denotes an annular recess that fits with the tip of the standing wall 35, and reference numeral 40 denotes a seal portion that seals between the pump case 20 and the separation plate 31 with a seal member interposed therebetween. The seal portion 40 suppresses leakage of fluid in the flow path 5 to the outer periphery. Reference numeral 41 denotes an insertion hole through which a fixture 43 for fixing the pump case 20 and the separation plate 31 is inserted, and the pump case 20 communicates with the insertion hole 41 and through which a fixture 43 such as a screw is inserted. 42 is formed.

  The predetermined clearance is wide enough that the dimensions do not come into contact with each other (the dimension does not become zero) even if the dimensions in the axial direction change due to parts crossing during pump assembly, etc., and the fluid does not flow easily. The gap is narrow enough.

  As another example of the embodiment, as shown in FIGS. 7 to 9, a reflux path is provided in the pump chamber 1 to return the accumulated gas to the upstream end 6 side (suction pipe 21 side) of the flow path 5. Self-priming performance may be improved. In addition, the substantially same structure as the above-mentioned example attaches | subjects the same code | symbol, and abbreviate | omits the overlapping description.

  The reflux path allows fluid (liquid or gas-liquid mixed fluid) flowing downstream from the flow path 5 to flow into the inner peripheral side from the flow path 5, and causes fluid on the inner peripheral side to flow out upstream from the flow path 5. The flow of fluid is generated in the space on the inner peripheral side from the flow path 5.

  Specifically, as shown in FIG. 9, the first groove portion 53 formed in the separation plate 31, the second groove portion 54 formed in the pump case 20, and the through passage 55 formed in the protruding portion 15 of the rotor 14 Are added to the vortex pump of the above-described example.

  The first groove portion 53 has a shape that is recessed in the axial direction from the one end surface 34 of the flange portion 33 along the radial direction from the connection portion with the standing wall 35 of the flange portion 33 to the inner peripheral end. The first groove portion 53 has an outer peripheral end that is open to an end surface facing the axial direction of the recess 36 via the standing wall 35.

  Further, as shown in FIG. 7, the opening of the first groove portion 53 is provided at a position rotated approximately 180 degrees from the suction communication hole 29 on the rotation circle, and communicates with the space formed by the recess 36. .

  Therefore, the first groove portion 53 is a substantially L-shaped groove (dent) as viewed in the rotational direction RD formed on the one end surface 34 and the wall surface, and the opening on the wall surface side of the first groove portion 53 is the flow path 5. It is located on the downstream side of the middle, and is a reflux path upstream end 51 for flowing fluid into the reflux path. The upstream end 51 of the reflux path is provided at a line target position rotated approximately 180 degrees from the suction communication hole 29.

  Further, the first groove portion 53 has a dimension between the bottom surface facing the axial direction formed on the one end surface 34 and the axial direction of the one plate surface 17, and the outer peripheral surface formed on the standing wall 35 and the disc 16. The dimensions between the outer peripheral ends in the radial direction are larger than the clearances. Therefore, the first groove portion 53 has a shape in which the fluid easily flows in the groove and the fluid easily flows into the groove from the flow path 5, and a part of the fluid flowing in the flow path 5 is part of the impeller 4. With rotation, the air flows into the inner circumferential space of the cylindrical portion 32 through the first groove portion 53. Hereinafter, the inner circumferential space of the cylindrical portion 32 is simply referred to as the inside of the cylindrical portion 32.

  Further, as shown in FIGS. 7 and 8, the second groove portion 54 is recessed in the axial direction from the flat surface 25 of the flat surface portion 24 along the radial direction from the inner peripheral end to the outer peripheral end of the flat surface portion 24. It is a substantially linear groove along the line. The outer peripheral end of the second groove portion 54 opens to the inner peripheral surface of the recessed portion 26, and the opening communicates with a position near the suction communication hole 29 in the space formed by the recessed portion 26. Therefore, the opening at the outer peripheral end is a reflux path downstream end 52 that returns the fluid in the reflux path to the upstream end 6 of the channel 5.

  Further, as shown in FIG. 9, the second groove portion 54 has a dimension in which the dimension between the inner circumferential plane 25 and the axial direction of the one plate surface 17 is larger than the clearance than the recess 26 formed in the plane section 24. It has become. Therefore, the second groove portion 54 has a shape in which the fluid easily flows in the groove and the fluid easily flows into the flow path 5 from the groove, and part of the fluid in the cylindrical portion 32 is rotated by the impeller 4. As a result, the refrigerant is returned to the upstream end 6 of the flow path 5 through the second groove portion 54.

  In order to allow fluid to flow from the inside of the cylindrical portion 32 to the second groove portion 54, the dimension between the outer peripheral surface of the fixed circular portion 23 of the pump case 20 and the radial direction of the inner peripheral end of the disc 16 is larger than the clearance. It is preferable to release with. Of course, the second groove portion 54 also has a groove on the outer peripheral surface of the fixed circular portion 23 along the axial direction from the inner peripheral end of the flat portion 24, and the cylindrical portion 32 extends from the axial end portion of the fixed circular portion 23. It may be a substantially L-shaped dent as viewed in the rotational direction RD communicating with the inside.

  The through passage 55 penetrates the projecting portion 15 of the rotor 14 along the axial direction, and a plurality of the through passages 55 are provided in the projecting portion 15. The through passage 55 has one end side (bottom side) in the cylindrical portion 32 and the projecting portion. Two spaces on the other end side (flange portion 33 side) sandwiching 15 are communicated.

  Therefore, the liquid in the cylindrical portion 32 flows from the one end side to the other end side or from the other end side to the one end side through the through passage 55 as the rotor 14 rotates. The gas staying in the cylinder is agitated to make the fluid in the cylindrical portion 32 a gas-liquid mixed fluid. As the liquid flows in from the flow path 5 via the first groove 53 and flows out to the flow path 5 via the second groove 54, the gas-liquid mixed fluid in the cylindrical portion 32 flows through the second groove 54. To the upstream end 6 of the flow path 5.

  Thus, by providing the reflux path, the flow from the downstream side to the upstream side of the flow path 5 via the first groove part 53 and the second groove part 54 is caused by the pressure difference between the downstream side and the upstream side of the flow path 5. The liquid in the passage 5 is refluxed, and the liquid and the staying gas are mixed when flowing around the axis during the reflux. Therefore, the liquid introduced into the reflux path from the downstream side of the flow path 5 becomes a gas-liquid mixed fluid and is led out to the upstream side of the flow path 5 from the reflux path, so that the staying gas in the cylindrical portion 32 can be reduced.

  And since a stagnant gas can be reduced, it can be made hard to generate | occur | produce the abnormal stop of pumps, such as a pump lock and shaft fixation accompanying the increase in a stagnant gas. Further, since the staying gas becomes a gas-liquid mixed fluid and flows in the flow path 5, the staying gas easily flows to the downstream end 7 of the flow path 5. The liquid is separated and sent out from the discharge pipe 22 to the outside.

  That is, by mixing the gas with the liquid in the cylindrical portion 32 and leading the mixed fluid to the upstream side of the flow path 5, it is possible to suppress the stagnation of the gas and improve the self-priming performance. The restriction on the posture of the pump at the time of installing the eddy current pump can be relaxed. The reflux path is not limited to a groove shape, and may be any shape that allows the inside of the flow path 5 and the cylindrical portion 32 to communicate with each other.

  Further, since a part of the fluid (liquid) in the flow path 5 flows to the reflux path by providing the reflux path, the fluid flowing to the discharge pipe 22 decreases, and the fluid pressure in the discharge pipe 22 is reduced. May decrease. And in order to reduce this pressure fall, as shown to FIG. 10, 11, the reflux path upstream end 51 which is an outer peripheral end of the 1st groove part 53 should be provided in the middle of the flow path 5, or downstream from the middle. preferable.

  FIG. 10 shows an example of the installation position of the reflux path upstream end 51. The installation position of the reflux path upstream end 51 is the first position 61, the second position 62, and the third position 63 in order from the upstream side of the flow path 5. , A fourth position 64 and a fifth position 65. FIG. 11 shows the analysis results of the motor rotation speed and the fluid pressure in the discharge pipe 22 according to the difference in the installation position of the reflux path upstream end 51. Each analysis result is one of the installation positions in FIG. This is the analysis result of the fluid flow when the reflux path upstream end 51 is provided.

  Hereinafter, the first quadrant E1, the first quadrant E1, and the second quadrant are respectively rotated 90 degrees clockwise (rotational direction RD) from the circumferential center of the discharge communication hole 30 and the suction communication hole 29 with the axis of the rotation circle of the impeller 4 as a reference point. The relationship between the installation position and the pressure drop will be described by dividing the second quadrant E2, the third quadrant E3, and the fourth quadrant E4.

  Specifically, as shown in FIG. 10, the first quadrant E1 is an area on the upstream end 6 (suction pipe 21) side of the flow path 5, and the fourth quadrant E4 is the downstream end 7 ( The region is on the discharge pipe 22) side.

  The second quadrant E2 is a region downstream from the upstream end 6 side (first quadrant E1) and upstream from the substantially middle of the flow path length, and the third quadrant E3 is the downstream end 7 side ( The region is upstream of the fourth quadrant E4) and downstream of the second quadrant E2.

  In addition, since the first position 61 opens on the second quadrant E2, and the second position 62 is located approximately in the middle of the flow path length (the boundary between the second quadrant E2 and the third quadrant E3), the second quadrant E2 and It opens on the third quadrant E3. The third position 63 is the position of the reflux path upstream end 51 in the examples shown in FIGS. 7 to 9, and the third position 63 opens on the third quadrant E3.

  Further, since the fourth position 64 is located at the boundary between the third quadrant E3 and the fourth quadrant E4, the fourth position 64 opens on the third quadrant E3 and the fourth quadrant E4, and the fifth position 65 opens on the fourth quadrant E4. ing. That is, at least a part of the second position 62, the third position 63, and the fourth position 64 is open on the third quadrant E3 that is in the middle of the flow path 5 or downstream from the middle.

  In addition, as shown in FIG. 11, the pressure drop is small at the second position 62, the third position 63, and the fourth position 64 opened on the third quadrant E3 as compared with the first position 61 and the fifth position 65. The pressure drop is the smallest at the third position 63. This is because at the first position 61, the fluid flows into the reflux path under insufficient pressure, and at the fifth position 65, there is too much inflow into the reflux path. This is thought to be because the pressure loss accompanying the decrease in pump efficiency increases.

  In this way, by opening the upstream end 51 of the reflux path on the third quadrant E3 which is the middle of the flow path 5 and the downstream side of the middle, the pressure drop due to the reflux path can be reduced, and the gas It becomes a vortex pump with good self-priming performance by suppressing abnormal stop due to stagnation. The upstream end 51 of the return path is not limited to the second position 62, the third position 63, and the fourth position 64, but between the second position 62 and the third position 63, or between the third position 63 and the fourth position 64. You may install between.

DESCRIPTION OF SYMBOLS 1 Pump chamber 4 Impeller 5 Flow path 6 Upstream end 7 Downstream end 18 Blade part 21 Suction pipe 22 Discharge pipe 27 Projection part 44 Collision surface

Claims (5)

The fluid flow includes: a blade portion that pressurizes fluid by rotation; an impeller having a blade portion on an outer periphery; a pump chamber that houses the impeller inside; and a motor that rotates the impeller. A flow path on the outer peripheral side of the impeller of the pump chamber,
A suction pipe that communicates with the upstream end of the flow path; a discharge pipe that communicates with the downstream end of the flow path; and a gas-liquid separation unit that performs gas-liquid separation of the fluid at the downstream end of the flow path. With
The casing that forms the pump chamber has a facing surface facing the axial direction of the impeller and the rotational axis of the impeller, and the inside of the discharge pipe extends from the facing surface along the axial direction to the pump chamber. Communicate with
Providing a projecting portion having a flat surface in the circumferential direction at a portion forming the downstream end of the facing surface,
The eddy current pump according to claim 1, wherein the flat surface of the protrusion is a collision surface that collides the fluid of the gas-liquid separation unit to perform gas-liquid separation.   The vortex pump according to claim 1, wherein the collision surface of the gas-liquid separation unit is flush with the inner surface of the discharge pipe along the axial direction.   The vortex pump according to claim 1 or 2, wherein the discharge pipe has a rectangular cross-sectional shape cut in a direction perpendicular to the fluid flow direction.   The pump chamber has a partition part that partitions between the downstream end and the upstream end of the flow path, and the partition part has a side wall on the downstream end side that is flush with the inner surface of the discharge pipe. The eddy current pump according to any one of claims 1 to 3.   A reflux path for refluxing gas at an upstream end is provided, and an upstream end of the reflux path is provided in the middle of the flow path or on the downstream side of the middle. The vortex pump according to item.

Images