JP2021120568A - Pump device - Google Patents

Abstract

To provide a pump device capable of suppressing the breakage of an impeller and a casing even when fluid is frozen in a pump chamber, and also suppressing a deterioration of pump performance.SOLUTION: A pump device 1 includes: a rotor 2 including an impeller 11, a shaft part 12 extending coaxially with the impeller 11, and a magnet 13 fixed to the shaft part 12 and separating from the impeller 11 in an axial direction L of the shaft part 12; and a casing 4 including a case 15 having a recessed part 41 storing the impeller 11, and a partition wall member 16 for partitioning a pump chamber 3 which is applied over the case 15 from the axial direction L and stores the case 15 and the rotor 2. On the partition wall member 16, at its opposed part 51 opposed to the impeller 11 in the axial direction L, an elastic member 25 and a partition member 26 overlapping with part of the elastic member 25 in view from the axial direction L are arranged.SELECTED DRAWING: Figure 2

Description

The present invention relates to a pump device that rotates an impeller in a pump chamber provided in a casing.

A pump device for rotating an impeller in a pump chamber provided in a casing is described in Patent Document 1. The pump device of the same document includes a rotor including an impeller and a magnet, a pump chamber for accommodating the rotor, a casing for partitioning the pump chamber, and a coil facing the magnet across the casing. The magnet is fixed at a position separated from the impeller in the axial direction of the impeller. Further, the pump device includes an elastic member arranged in the pump chamber in order to prevent the casing from being damaged during freezing. The elastic member is arranged in the axial direction on the side opposite to the impeller with respect to the magnet.

JP-A-2002-227791

The pump chamber is partitioned by a case provided with a recess for accommodating the impeller and a partition member arranged between the rotor and the stator and covering the case from the axial direction. In the pump device of Patent Document 1, the partition wall member includes a facing portion facing the impeller from the axial direction. Since the elastic member is arranged on the opposite portion of the partition wall member in the pump chamber, the capacity of the pump chamber can be expanded around the impeller and damage to the casing can be suppressed.

However, when the elastic member is arranged on the opposite portion of the partition wall member, the elastic member is deformed by the pressure when the pump device is operated, and the gap between the elastic member and the impeller is widened. When the gap between the elastic member and the impeller changes, the size of the gap through which the fluid flows changes. Therefore, there is a concern that the lift will decrease, and there is a concern that the pump performance will decrease.

In view of these points, an object of the present invention is to provide a pump device capable of suppressing damage to the casing and suppressing deterioration of pump performance even when the fluid freezes in the pump chamber. be.

In order to solve the above problems, the pump device of the present invention includes an impeller, a shaft portion extending coaxially with the impeller, and a magnet fixed to the shaft portion and separated from the impeller in the axial direction of the shaft portion. A casing including a rotor, a case provided with a recess for accommodating the impeller, and a partition wall member which is placed on the case from the axial direction and partitions the pump chamber for accommodating the rotor together with the case, and the partition wall member. The partition member has an elastic member arranged on an opposing portion facing the impeller in the axial direction, and a partition member arranged between the elastic member and the impeller and fixed to the partition wall member. , It is characterized in that it overlaps with a part of the elastic member when viewed from the axial direction.

According to the present invention, the partition wall member for partitioning the pump chamber includes a facing portion facing the impeller in the axial direction, and an elastic member is arranged at the facing portion. Further, the partition member arranged between the elastic member and the impeller overlaps a part of the elastic member. Therefore, since a part of the elastic member is exposed in the pump chamber, when the volume of the fluid remaining in the pump chamber increases due to freezing, the elastic member is compressed around the impeller where the space where the fluid exists in the pump chamber is large. The capacity of the pump chamber is expanded. As a result, the pressure applied to the inner wall surface of the pump chamber when the fluid freezes can be reduced, so that damage to the casing can be suppressed. Further, since the elastic member can be positioned by the partition member, it is possible to prevent the elastic member from being deformed by the pressure of the fluid when the pump device is operating and the distance between the impeller and the elastic member from being widened. Therefore, since it is possible to suppress a decrease in the lift due to the arrangement of the elastic member in the pump chamber, it is possible to suppress damage to the casing when the fluid freezes and to suppress a decrease in pump performance.

In the present invention, the facing portion includes an annular bottom portion, an inner peripheral wall portion extending in the axial direction from the inner peripheral edge of the bottom portion, and an outer peripheral wall portion extending in the axial direction from the outer peripheral edge of the bottom portion. The elastic member is arranged in an annular elastic member accommodating recess surrounded by the bottom portion, the inner peripheral wall portion, and the outer peripheral wall portion, and the height of the outer peripheral wall portion in the axial direction is the axial direction of the elastic member. It is preferably lower than the height of. In this way, the outer peripheral surface of the elastic member is exposed inside the pump chamber, so that when the pump device is operating, the pressure of the fluid acts on the outer peripheral surface of the elastic member and the elastic member is compressed to the inner peripheral side. Will be done. As a result, it is possible to suppress an increase in the distance between the impeller and the elastic member, so that it is possible to suppress a decrease in the lift and a decrease in pump performance.

In the present invention, it is preferable that the partition member is annular and the outer diameter of the partition member is smaller than the outer diameter of the elastic member. In this way, the outer peripheral portion of the elastic member can be exposed in the pump chamber.

In the present invention, the partition member is preferably welded to the welded portion provided on the inner peripheral wall portion. In this way, no fixed parts are required. In addition, the fixing strength of the partition member can be increased.

In the present invention, the inner peripheral wall portion preferably includes a mounting surface on which the partition member abuts in the axial direction. In this way, the partition member can be positioned in the axial direction. Therefore, the elastic member can be positioned in the axial direction via the partition member.

In the present invention, the partition member is preferably a flexible sheet member. In this way, the partition member can appropriately suppress the deformation of the elastic member. Therefore, damage to the casing can be suppressed when the fluid freezes, and deformation of the elastic member due to the pressure of the fluid can be suppressed when the pump device is operating. Therefore, deterioration of pump performance can be suppressed.

In the present invention, the elastic member is a closed cell foam. By using the closed cell foam, the capacity of the pump chamber can be expanded by compressing the elastic member during freezing.

According to the present invention, the partition wall member for partitioning the pump chamber includes a facing portion facing the impeller in the axial direction, and an elastic member is arranged at the facing portion. Further, the partition member arranged between the elastic member and the impeller overlaps a part of the elastic member. Therefore, since a part of the elastic member is exposed in the pump chamber, when the volume of the fluid remaining in the pump chamber increases due to freezing, the elastic member is compressed around the impeller where the space where the fluid exists in the pump chamber is large. The capacity of the pump chamber is expanded. As a result, the pressure applied to the inner wall surface of the pump chamber when the fluid freezes can be reduced, so that damage to the casing can be suppressed. Further, since the elastic member can be positioned by the partition member, it is possible to prevent the elastic member from being deformed by the pressure of the fluid when the pump device is operating and the distance between the impeller and the elastic member from being widened. Therefore, since it is possible to suppress a decrease in the lift due to the arrangement of the elastic member in the pump chamber, it is possible to suppress damage to the casing when the fluid freezes and to suppress a decrease in pump performance.

It is external perspective view of the pump device to which this invention was applied. It is sectional drawing of the pump device of FIG. FIG. 5 is an exploded perspective view of the pump device of FIG. 1 as viewed from one side in the axial direction. It is a perspective view which looked at the case from the other side in the axial direction. It is a perspective view which looked at the partition wall member and the frost weathering prevention part from one side in the axial direction. It is an exploded perspective view of a partition wall member and a frost weathering prevention part. It is a partial cross-sectional view (partial cross-sectional view of the region A of FIG. 2) of the frost weathering prevention part.

Hereinafter, embodiments of a pump device to which the present invention is applied will be described with reference to the drawings.

(overall structure)
FIG. 1 is an external perspective view of a pump device 1 to which the present invention is applied. FIG. 2 is a cross-sectional view of the pump device 1 of FIG. FIG. 3 is an exploded perspective view of the pump device 1 of FIG. 1 as viewed from one side L1 of the axial direction L. The pump device 1 of this embodiment is mounted on a device such as a water heater, a washing machine, and a dishwasher. The pump device 1 supplies a fluid such as tap water to the device.

As shown in FIG. 2, the pump device 1 includes a rotor 2 and a pump chamber 3 that houses the rotor 2. Further, the pump device 1 includes a casing 4 for partitioning the pump chamber 3. Further, the pump device 1 includes a motor mechanism unit 5 for rotating the rotor 2. In the present specification, the direction along the rotation axis of the rotor 2 is defined as the axis direction L. Further, one side of the axial direction L is L1, and the other side of the axial direction L is L2.

As shown in FIGS. 2 and 3, the rotor 2 includes an impeller 11, a shaft portion 12 coaxially extending from the impeller 11, and an annular magnet 13 fixed to the shaft portion 12. The impeller 11 and the magnet 13 are provided at positions separated from each other in the axial direction L. The impeller 11 is located on one side L1 of the axial direction L, and the magnet 13 is located on the other side L2 of the axial direction L.

As shown in FIG. 2, the casing 4 includes a case 15 and a partition member 16. The case 15 and the partition wall member 16 are overlapped in the axial direction L. The pump chamber 3 is formed between the case 15 and the partition member 16. The case 15 includes a water supply pipe 43 and a discharge pipe 44 that communicate with the pump chamber 3. The water supply pipe 43 projects to one side L1 of the axial direction L, and the discharge pipe 44 extends to the outer peripheral side of the case 15. The pump device 1 sends out the fluid sucked from the water supply pipe 43 into the pump chamber 3 from the discharge pipe 44.

As shown in FIG. 2, the motor mechanism portion 5 includes a stator 17 that surrounds the magnet 13 from the outside in the radial direction on the side opposite to the pump chamber 3 with respect to the partition wall member 16. The stator 17 includes a stator core 18 and a plurality of coils 19. The stator core 18 and the coil 19 together with the magnet 13 of the rotor 2 constitute the motor mechanism portion 5.

Further, the pump device 1 is made of a circuit board 21 to which the end of the winding of the coil 19 is connected, a resin sealing member 22 covering the stator 17 and the circuit board 21, and a metal fixed to the resin sealing member 22. The base member 23 of the above is provided. The resin sealing member 22 constitutes a part of the exterior of the pump device 1.

Further, the pump device 1 includes an elastic member 25 arranged in the pump chamber 3 and a partition member 26 for positioning the elastic member 25 in the axial direction L. The elastic member 25 is compressed when the fluid remaining in the pump chamber 3 freezes to increase the volume of the pump chamber 3. As a result, the pressure applied to the casing 4 and the impeller 11 when the fluid remaining in the pump chamber 3 freezes is reduced. Therefore, the elastic member 25 and the partition member 26 form a frost weathering prevention portion 29 for preventing damage to the casing 4 and the impeller 11.

(Rotor)
As shown in FIGS. 2 and 3, the impeller 11 is formed on a first annular plate portion 31 having an annular shape when viewed from the axial direction L and on the other side L2 of the first annular plate portion 31 in the axial direction L. It includes a second annular plate portion 32 that is located in an annular shape, and a plurality of blades 33 provided between the first annular plate portion 31 and the second annular plate portion 32. The first annular plate portion 31 is slightly inclined from the inner peripheral side to the outer peripheral side toward the other side L2 in the axial direction L. Further, the first annular plate portion 31 includes an annular protrusion 31a projecting from the inner peripheral side edge to one side L1 in the axial direction L. The second annular plate portion 32 overlaps with the first annular plate portion 31 when viewed from the axial direction L. Each of the plurality of blades 33 extends between the first annular plate portion 31 and the second annular plate portion 32 so as to be curved forward in the rotation direction R from the inner peripheral side toward the outer peripheral side. In the present embodiment, each blade 33 is a rib protruding from the first annular plate portion 31 to the other side L2 in the axial direction L. The second annular plate portion 32 is connected to the end of each blade 33 on the other side L2 in the axial direction L by ultrasonic welding.

The shaft portion 12 has a tubular shape and includes a shaft hole 12a penetrating in the axial direction L. The shaft portion 12 extends from the inner peripheral end edge of the second annular plate portion 32 of the impeller 11 to the other side L2 in the axial direction L. As shown in FIG. 2, a sleeve 35, which is a sliding bearing, is fixed inside the shaft hole 12a. A support shaft 40 that rotatably supports the rotor 2 is inserted into the center hole of the sleeve 35. The support shaft 40 is made of stainless steel and extends in the axial direction L. The end of one side L1 of the axial direction L of the support shaft 40 is supported by the case 15, and the end of the other side L2 of the axial direction L is supported by the partition member 16.

The shaft portion 12 includes a flange portion 36 that projects from the middle of the axial direction L toward the outer peripheral side. As shown in FIGS. 2 and 2, on the outer peripheral surface of the shaft portion 12, the magnet 13 is fixed to the region of the flange portion 36 on the other side L2 in the axial direction L. The magnet 13 has an annular shape, and S poles and N poles are alternately magnetized in the circumferential direction.

(casing)
FIG. 4 is a perspective view of the case 15 as viewed from the other side L2 in the axial direction L. As shown in FIGS. 2 and 4, the case 15 has a case main body 42 having a recess 41 for accommodating the impeller 11, a water supply pipe 43 having a water supply flow path communicating with the recess 41, and a discharge communicating with the recess 41. A discharge pipe 44 provided with a flow path is provided.

The recess 41 includes an annular bottom surface 41a and a cylindrical inner peripheral surface 41b extending from the outer peripheral edge of the bottom surface 41a to the other side L2 in the axial direction L. A pump chamber side opening 43a of the water supply pipe 43 is provided in the center of the bottom surface 41a. An annular step 45 is provided on the inner peripheral edge of the pump chamber side opening 43a. Further, the bottom surface 41a is provided with an annular recess 46 surrounding the annular step portion 45. A pump chamber side opening 44a of the discharge pipe 44 is provided in a part of the inner peripheral surface 41b of the recess 41 in the circumferential direction. The discharge pipe 44 extends in the tangential direction of the inner peripheral surface 41b.

The case 15 includes a case-side rotor support portion 47 extending in the axial direction L at the center of the concave portion 41 in the radial direction. The case-side rotor support portion 47 is located in front of the inflow direction of the fluid flowing in from the pump chamber-side opening 43a of the water supply pipe 43. The case-side rotor support portion 47 is supported by three leg portions 48 projecting from the inner wall surface of the pump chamber-side opening 43a to the other side L2 in the axial direction L.

As shown in FIG. 2, the end portion of one side L1 of the axial direction L of the support shaft 40 protruding from the sleeve 35 of the rotor 2 toward the case 15 is inserted into the case-side rotor support portion 47. A washer 50 is arranged between the sleeve 35 and the case-side rotor support portion 47. The sleeve 35 and the case-side rotor support portion 47 come into contact with each other in the axial direction L via the washer 50.

As shown in FIG. 2, the partition wall member 16 forms a recessed space for accommodating the shaft portion 12 of the rotor 2 and the magnet 13 on the other side of the impeller 11 in the axial direction L, and is arranged on the outer peripheral side of the magnet 13. Shields the fluid from the stator 17. The partition wall member 16 extends from the other side L2 in the axial direction L to the annular facing portion 51 facing the impeller 11, and the end edge on the inner peripheral side of the facing portion 51 to the other side L2 in the axial direction L, and extends the magnet 13 to the outer peripheral side. A cylinder portion 52 surrounding the cylinder portion 52 and a sealing portion 53 for sealing the end portion of the other side L2 of the cylinder portion 52 in the axial direction L are provided. The facing portion 51 faces the bottom surface 41a of the recess 41 of the case body 42 via the impeller 11.

As will be described later, the facing portion 51 of the partition wall member 16 includes an annular elastic member accommodating recess 510 that opens on one side L1 of the axial direction L. An elastic member 25 constituting the frost weathering prevention portion 29 is arranged in the elastic member accommodating recess 510. Further, a flange portion 55 extending outward in the radial direction is connected to the outer peripheral edge of the facing portion 51.

As shown in FIG. 2, in the partition wall member 16, the facing portion 51 is fitted inside the recess 41 of the case body 42, and the flange portion 55 hits the end surface of the other side L2 of the case body 42 in the axial direction L. Get in touch. An annular step portion 57 that is recessed radially outward from the inner peripheral surface 41b is provided at the opening edge of the recess 41 on the other side L2 in the axial direction L. An O-ring 58 is arranged on the step portion 57. The O-ring 58 seals between the case body 42 and the partition member 16 in a state of being compressed in the radial direction between the case body 42 and the outer peripheral surface of the facing portion 51.

As shown in FIG. 2, the partition wall member 16 includes a partition wall member side rotor support portion 62 projecting from the central portion of the blockade portion 53 to one side L1 in the axial direction L. The partition wall member-side rotor support portion 62 includes a support shaft fixing recess 63 that opens at the end surface of one side L1 in the axial direction L. The end of the other side L2 of the support shaft 40 in the axial direction L is inserted into the support shaft fixing recess 63.

The partition wall member side rotor support portion 62 is inserted into the shaft hole 12a of the shaft portion 12 of the rotor 2 from the other side L2 in the axial direction L. There is a gap between the outer peripheral surface of the partition member side rotor support portion 62 and the inner wall surface of the shaft hole 12a. The sleeve 35 is located on one side L1 of the rotor support portion 62 on the partition wall member side in the axial direction L. When the pump device 1 operates and the impeller 11 rotates, the rotor 2 is displaced to one side L1 in the axial direction L, and the end face of the one side L1 in the axial direction L of the bulkhead member side rotor support 62 and the sleeve 35. A gap is formed between the two.

The inner peripheral surface (bottom surface 41a and inner peripheral surface 41b) of the recess 41 of the case body 42, the surface of one side L1 of the axial direction L of the facing portion 51 of the partition wall member 16, the inner peripheral surface of the tubular portion 52, and the sealing portion 53. The end surface of one side L1 of the axial direction L constitutes the inner wall surface of the pump chamber 3.

(Stator)
As shown in FIG. 2, the stator 17 is arranged on the outer peripheral side of the tubular portion 52 of the partition wall member 16. The stator 17 includes a stator core 18 having a plurality of cores arranged in an annular shape, and a plurality of coils 19 wound around salient poles 66 provided on each core via an insulator 67. The end faces on the inner peripheral side of each salient pole 66 face the magnet 13 of the rotor 2 in the radial direction via the tubular portion 52.

In this embodiment, the motor mechanism unit 5 is a three-phase brushless motor. That is, in this embodiment, nine salient poles 66 are provided, and the nine coils 19 wound around each salient pole 66 are three U-phase coils 19, three V-phase coils 19, and three. W-phase coil 19 is configured. Further, these nine coils 19 are arranged so that the U-phase coil 19, the V-phase coil 19, and the W-phase coil 19 are repeatedly arranged in this order.

As shown in FIG. 2, the circuit board 21 is arranged on the other side L2 of the sealing portion 53 of the partition wall member 16 in the axial direction L. The end of the winding drawn from the coil 19 of the stator 17 is electrically connected to the circuit board 21. A connector 68 is attached to the circuit board 21. The stator 17 and the circuit board 21 are sealed by the resin sealing member 22. The resin sealing member 22 is a BMC (Bulk Molding Compound) which is a thermosetting resin material.

The base member 23 is fixed to the end surface of the resin sealing member 22 on the other side L2 in the axial direction L. The base member 23 is a reinforcing member that reinforces the resin sealing member 22. The base member 23 has a disk shape and is provided with screw holes 23a at four locations around the axis on the outer peripheral edge.

As shown in FIG. 1, the resin sealing member 22 constitutes a part of the exterior of the pump device 1. As shown in FIG. 3, the case 15 is provided with case-side through holes 15a penetrating in the axial direction L at four locations in the circumferential direction. Further, the partition wall member 16 is provided with partition wall member side through holes 16a penetrating in the axial direction L at four locations in the circumferential direction. Further, the resin sealing member 22 is provided with resin sealing member side through holes 22a penetrating in the axial direction L at four locations in the circumferential direction. The case 15 has a through hole 15a on the case side, a through hole on the resin sealing member 22 side, and a through hole 22a on the resin sealing member side in the axial direction L, and is screwed into the screw hole 23a of the base member 23. It is fixed to the partition member 16 by a head screw 69 (see FIG. 1).

When driving the pump device 1, electric power is supplied to each coil 19 of the stator 17 in a predetermined order to rotate the rotor 2. As a result, the impeller 11 rotates in the predetermined rotation direction R, so that the fluid flows in the circumferential direction in the pump chamber 3. Therefore, the fluid is sucked into the pump chamber 3 from the water supply pipe 43, and the fluid is discharged from the discharge pipe 44.

(Frost weathering prevention unit)
In the pump device 1 of the present embodiment, on the inner wall surface of the pump chamber 3, a frost weathering prevention portion 29 is provided on an facing portion 51 which is an inner wall surface portion facing the impeller 11 from the other side L2 in the axial direction L. There is. The frost weathering prevention unit 29 includes an elastic member 25 that is arranged in the pump chamber 3 and is compressed when the fluid freezes, and a partition member 26 that positions the elastic member 25 in the axial direction L.

FIG. 5 is a perspective view of the partition wall member 16 and the frost weathering prevention portion 29 as viewed from the other side in the axial direction L. FIG. 6 is an exploded perspective view of the partition wall member 16 and the frost weathering prevention unit 29. FIG. 7 is a partial cross-sectional view of the frost weathering prevention portion 29, and is a partial cross-sectional view of the region A of FIG. As shown in FIGS. 6 and 7, the facing portion 51 of the partition wall member 16 includes an annular bottom portion 511 and an inner peripheral wall portion 512 extending from the inner peripheral edge of the bottom portion 511 toward the case 15 on one side L1 of the axial direction L. An outer peripheral wall portion 513 extending from the outer peripheral edge of the bottom portion 511 toward the case 15 on one side L1 in the axial direction L is provided. The elastic member accommodating recess 510 is an annular groove surrounded by a bottom portion 511, an inner peripheral wall portion 512, and an outer peripheral wall portion 513. The inner peripheral wall portion 512 is connected to the end portion of one side L1 of the tubular portion 52 in the axial direction L. Further, the outer peripheral wall portion 513 is fitted inside the opening edge of the recess 41. The flange portion 55 is connected to the end portion of the outer peripheral wall portion 513 on the other side L2 in the axial direction L.

As shown in FIGS. 5 and 6, the elastic member 25 has an annular shape and is arranged in the elastic member accommodating recess 510. The partition member 26 is annular and is arranged between the elastic member 25 and the impeller 11 (see FIG. 2). The partition member 26 overlaps a part of the elastic member 25 when viewed from the axial direction L. As shown in FIGS. 5 and 7, in the present embodiment, the outer diameter of the partition member 26 is smaller than the outer diameter of the elastic member 25, so that the partition member 26 is the inner peripheral portion of the elastic member 25 when viewed from the axial direction L. Overlaps with. Therefore, the end surface of one side L1 of the elastic member 25 in the axial direction L includes a first exposed portion 251 that is exposed in the pump chamber 3 without being covered by the partition member 26.

As shown in FIG. 7, in the present embodiment, the height H1 in the axial direction L of the outer peripheral wall portion 513 arranged on the outer peripheral side of the elastic member 25 is smaller than the height H0 in the axial direction L of the elastic member 25. Therefore, the outer peripheral surface of the elastic member 25 includes a second exposed portion 252 that is exposed in the pump chamber 3 without being covered by the outer peripheral wall portion 513.

The elastic member 25 is a closed cell foam. In this embodiment, the elastic member 25 is EPDM (ethylene propylene diene rubber). For example, examples of the elastic member 25 include Teflon (registered trademark) and nitrile rubber. The elastic member 25 is provided with a smooth surface on which air bubbles are not exposed, at least on the surface facing the impeller 11 and the outer peripheral surface. The elastic member 25 has a size capable of absorbing the volume integral of the fluid that increases due to freezing when the fluid remaining in the pump chamber 3 freezes due to the elastic deformation of the elastic member 25. In the present embodiment, the elastic member 25 has a size capable of elastic deformation of 10% or more of the volume of the pump chamber 3 or more, which is equal to or more than the volume integral, when the elastic member 25 changes from the natural state to the compressed state.

The partition member 26 is welded to the welded portion 514 provided on the inner peripheral wall portion 512. As shown in FIG. 6, at the tip of the inner peripheral wall portion 512, an annular mounting surface 515 and an annular convex portion 516 protruding toward one side L1 of the axial direction L on the inner peripheral side of the mounting surface 515 are provided. Has been done. The annular convex portion 516 is fitted on the inner peripheral side of the partition member 26, and the partition member 26 abuts on the mounting surface 515 from one side L1 in the axial direction L. As a result, the partition member 26 is positioned in the axial direction L. The welded portion 514 is a convex portion protruding from the mounting surface 515. In this embodiment, the welded portions 514 are formed at eight locations and are arranged at equal intervals in the circumferential direction. Each welding portion 514 is arranged in a welding notch portion 261 provided on the inner peripheral edge of the partition member 26. By heating and crushing each welded portion 514, the partition member 26 is heat-welded to the partition wall member 16.

The partition member 26 is a flexible sheet member such as a polyethylene film (PET film). For example, as the partition member 26, Lumirror (registered trademark) manufactured by Toray Industries, Inc. can be exemplified. As the partition member 26, a sheet member made of another material can also be used. Alternatively, a sheet metal member can be used as the partition member 26.

In the freezing test, it was confirmed that the pump device 1 provided with the frost weathering prevention unit 29 of the present embodiment did not crack the casing 4 and did not damage the impeller 11. Further, since the elastic member 25 having a large volume is arranged on the facing portion 51 facing the impeller 11 in the axial direction L, the lift is lowered as compared with the case where the elastic member 25 is not arranged, but a part of the elastic member 25. It was confirmed that the decrease in the lift was suppressed and the decrease in the pump characteristics was suppressed by covering the surface with the partition member 26.

(Main action and effect of this form)
As described above, the pump device 1 of the present embodiment includes the impeller 11, the shaft portion 12 extending coaxially with the impeller 11, and the magnet 13 fixed to the shaft portion 12 and separated from the impeller 11 in the axial direction L of the shaft portion 12. A rotor 2 including the rotor 2, a case 15 including a recess 41 accommodating the impeller 11, and a partition member 16 covering the case 15 from the axial direction L and partitioning the pump chamber 3 accommodating the rotor 2 together with the case 15. A partition arranged between the casing 4, the elastic member 25 arranged on the facing portion 51 facing the impeller 11 and the impeller 11 in the partition wall member 16 in the axial direction L, and the elastic member 25 and the impeller 11 and fixed to the partition wall member 16. It has a member 26 and. The partition member 26 overlaps a part of the elastic member 25 when viewed from the axial direction L.

According to this embodiment, since a part of the elastic member 25 arranged in the facing portion 51 facing the impeller 11 in the axial direction L is exposed in the pump chamber 3, the volume of the fluid remaining in the pump chamber 3 due to freezing. When is increased, the elastic member 25 is compressed around the impeller 11 in which the space where the fluid exists in the pump chamber 3 is large, and the capacity of the pump chamber 3 is expanded. As a result, the pressure applied to the inner wall surface of the pump chamber 3 when the fluid is frozen can be reduced, so that damage to the casing 4 can be suppressed. Further, since the elastic member 25 can be positioned by the partition member 26, it is possible to prevent the elastic member 25 from being deformed by the pressure of the fluid when the pump device is operating and the distance between the impeller 11 and the elastic member 25 from being widened. Therefore, even when the elastic member 25 having a large volume is arranged in the pump chamber 3, it is possible to prevent the distance between the impeller 11 and the elastic member 25 from being widened and the lift from being lowered. Therefore, damage to the casing 4 can be suppressed when the fluid freezes, and deterioration of pump performance can be suppressed.

In proposing the pump device 1 of this embodiment, the following items are taken into consideration. When the fluid remaining in the connecting pipe connected to the pump chamber, water supply pipe, and discharge pipe in the pump device freezes due to cold weather, etc., the fluid tends to remain in the space around the impeller near the connecting pipe in the pump chamber. Volume expansion of the fluid due to freezing is likely to occur around the impeller. Conventionally, a pump device in which an elastic member is arranged at a position separated from an impeller has been proposed. However, in such a configuration, when the fluid starts to freeze around the impeller, the capacity of the pump chamber cannot be expanded around the impeller to absorb the volume expansion of the fluid, and the casing may be damaged. there were. As described above, the pump device 1 of the present embodiment is configured such that the elastic member 25 is compressed around the impeller 11 to expand the capacity of the pump chamber 3, so that damage to the casing 4 can be suppressed.

In the present embodiment, the facing portion 51 has an annular bottom portion 511, an inner peripheral wall portion 512 extending in the axial direction L from the inner peripheral edge of the bottom portion 511 toward the case 15, and an axial direction from the outer peripheral edge of the bottom portion 511 toward the case 15. An outer peripheral wall portion 513 extending to L is provided, and the elastic member 25 is arranged in an elastic member accommodating recess 510 surrounded by a bottom portion 511, an inner peripheral wall portion 512, and an outer peripheral wall portion 513. The height H1 in the axial direction L of the outer peripheral wall portion 513 is lower than the height H0 in the axial direction L of the elastic member 25. Therefore, since a part of the outer peripheral surface of the elastic member 25 is exposed in the pump chamber 3, when the pump device 1 is operating, the pressure of the fluid acts on the outer peripheral surface of the elastic member 25 to act on the elastic member 25. Is compressed to the inner circumference side. Therefore, since it is possible to suppress an increase in the distance between the impeller 11 and the elastic member 25 in the axial direction L, it is possible to suppress a decrease in the lift and a decrease in pump performance.

In this embodiment, the partition member 26 is annular, and the outer diameter of the partition member 26 is smaller than the outer diameter of the elastic member 25. Therefore, since the outer peripheral portion of the elastic member 25 can be exposed in the pump chamber 3, the elastic member 25 can be compressed during freezing to reduce the pressure applied to the inner wall surface of the pump chamber 3.

In the present embodiment, the inner peripheral wall portion 512 of the facing portion 51 includes a mounting surface 515 on which the partition member 26 abuts in the axial direction L. Therefore, the partition member 26 can be positioned in the axial direction L. Further, the elastic member 25 can be positioned in the axial direction L via the partition member 26.

In the present embodiment, the partition member 26 is welded to the welded portion 514 provided on the inner peripheral wall portion 512, so that no fixing component is required. In addition, the fixing strength of the partition member 26 can be increased.

In the present embodiment, since the partition member 26 is a flexible sheet member, the partition member 26 can appropriately suppress the deformation of the elastic member 25. Therefore, damage to the casing 4 can be suppressed when the fluid freezes, and deformation of the elastic member 25 due to the pressure of the fluid can be suppressed when the pump device 1 is operating. Therefore, deterioration of pump performance can be suppressed.

In this embodiment, the elastic member 25 is a closed cell foam. By using the closed cell foam, the capacity of the pump chamber 3 can be expanded by compressing the elastic member 25 at the time of freezing.

1 ... Pump device, 2 ... Rotor, 3 ... Pump chamber, 4 ... Casing, 5 ... Motor mechanism, 11 ... Impeller, 12a ... Shaft hole, 12 ... Shaft, 13 ... Magnet, 15 ... Case, 15a ... Case side Through hole, 16 ... partition wall member, 16a ... partition wall member side through hole, 17 ... stator, 18 ... stator core, 19 ... coil, 21 ... circuit board, 22 ... resin sealing member, 22a ... resin sealing member side through hole, 23 ... Base member, 23a ... Screw hole, 25 ... Elastic member, 26 ... Partition member, 29 ... Freezing breakage prevention part, 31 ... First annular plate part, 31a ... Ring protrusion, 32 ... Second annular plate part, 33 ... blade, 35 ... sleeve, 36 ... flange, 40 ... support shaft, 41 ... recess, 41a ... bottom surface, 41b ... inner peripheral surface, 42 ... case body, 43 ... water supply pipe, 43a ... pump chamber side opening, 44 ... Discharge pipe, 44a ... Pump chamber side opening, 45 ... Ring step, 46 ... Ring recess, 47 ... Case side rotor support, 48 ... Leg, 49 ... Welding, 49a ... Protrusion, 49b ... End face of protrusion , 50 ... Washer, 51 ... Opposing part, 52 ... Cylinder part, 53 ... Sealing part, 55 ... Flange part, 57 ... Step part, 58 ... O-ring, 62 ... Bulkhead member side rotor support part, 63 ... For fixing support shaft Recess, 66 ... salient pole, 67 ... insulator, 68 ... connector, 69 ... screw, 251 ... first exposed part, 252 ... second exposed part, 261 ... welding notch, 510 ... elastic member accommodating recess, 511 ... Bottom, 512 ... Inner peripheral wall, 513 ... Outer peripheral wall, 514 ... Welding, 515 ... Mounting surface, 516 ... Circular convex, L ... Axial direction, L1 ... One side, L2 ... Other side, R ... Rotation direction

Claims (7)

A rotor including an impeller, a shaft portion coaxial with the impeller, and a magnet fixed to the shaft portion and separated from the impeller in the axial direction of the shaft portion.
A casing including a case provided with a recess for accommodating the impeller, and a partition member which is placed on the case from the axial direction and partitions the pump chamber for accommodating the rotor together with the case.
In the partition wall member, an elastic member arranged at a portion facing the impeller in the axial direction and
It has a partition member arranged between the elastic member and the impeller and fixed to the partition wall member.
A pump device characterized in that the partition member overlaps a part of the elastic member when viewed from the axial direction. The facing portion includes an annular bottom portion, an inner peripheral wall portion extending in the axial direction from the inner peripheral edge of the bottom portion, and an outer peripheral wall portion extending in the axial direction from the outer peripheral edge of the bottom portion.
The elastic member is arranged in an annular elastic member accommodating recess surrounded by the bottom portion, the inner peripheral wall portion, and the outer peripheral wall portion.
The pump device according to claim 1, wherein the height of the outer peripheral wall portion in the axial direction is lower than the height of the elastic member in the axial direction. The partition member is annular and
The pump device according to claim 2, wherein the outer diameter of the partition member is smaller than the outer diameter of the elastic member. The pump device according to claim 2 or 3, wherein the partition member is welded to a welding portion provided on the inner peripheral wall portion. The pump device according to any one of claims 2 to 4, wherein the inner peripheral wall portion includes a mounting surface on which the partition member abuts in the axial direction. The pump device according to any one of claims 1 to 5, wherein the partition member is a flexible sheet member. The pump device according to any one of claims 1 to 6, wherein the elastic member is a closed cell foam.

Images