JP2021036134A - Pump device - Google Patents

Abstract

To provide a pump in which an impeller is not broken even if fluid is frozen.SOLUTION: A pump device 1A has an impeller 11, a shaft part 12 extending coaxially with the impeller 11, a rotor 2 having a magnet 13 fixed to the shaft part 12, and a pump chamber 3 for accommodating the rotor 2. An elastic member 25 is fixed to an opposing face 51a of an annular part 51 of a bulkhead member 16 opposing the impeller 11 at an inner wall face 3a of the pump chamber 3. When a volume of fluid remaining in the pump chamber 3 by a freeze is increased, the elastic member 25 is compressed at a periphery of the impeller 11 whose space in which the fluid exists in the pump chamber 3 is large, and a capacity of the pump chamber 3 is enlarged, thus not causing the breakage of the impeller 11.SELECTED DRAWING: Figure 2

Description

The present invention relates to a pump device capable of suppressing damage to the impeller even when a fluid such as water freezes in the pump chamber.

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 along the rotation axis 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 compressed to increase the volume of the pump chamber when the volume of fluid in the pump chamber increases due to freezing. As a result, the pressure applied to the casing from the frozen fluid can be reduced, and the casing can be avoided from being damaged. 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

In Patent Document 1, the elastic member is arranged at a position away from the impeller. However, in the pump chamber, since the space around the impeller where the fluid exists is large, the capacity of the pump chamber cannot be expanded around the impeller at the time of freezing, and the impeller may be damaged.

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

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. The rotor and the pump chamber for accommodating the rotor are provided, and the inner wall surface portion of the inner wall surface of the pump chamber facing the impeller and at least one of the impeller and the magnet in the rotor have a rotor and a pump chamber. It is characterized in that the elastic member is fixed.

According to this example, an elastic member is provided in the pump chamber. Further, the elastic member is fixed to at least one of the inner wall surface portion facing the impeller on the inner wall surface of the pump chamber and the impeller and the magnet in the rotor. Therefore, when the volume of the fluid remaining in the pump chamber increases due to freezing, the elastic member is compressed around the impeller in which the space where the fluid exists in the pump chamber is large, and the capacity of the pump chamber is expanded. As a result, the pressure applied to the impeller from the fluid whose volume has increased can be reduced, so that damage to the impeller can be prevented or suppressed. Further, since the pressure applied to the inner wall surface of the pump chamber from the fluid whose volume has increased can be reduced, damage to the pump chamber, that is, damage to the casing can be prevented or suppressed.

In the present invention, a case body having a recess for accommodating an impeller, a case having a water suction port communicating with the recess, and a discharge port communicating with the recess, and a case covered with the case from the axial direction and the pump together with the case. It has a partition wall member for partitioning a chamber, and the partition wall member extends in the axial direction from an annular portion facing the impeller from a side opposite to the case body and an edge on the inner peripheral side of the annular portion. The elastic member shall be fixed to the annular portion, including a tubular portion that surrounds the magnet from the outer peripheral side and a sealing portion that seals the end portion of the tubular portion on the side opposite to the annular portion. Can be done. If the elastic member is arranged at such a position, it is possible to prevent the elastic member from obstructing the flow of the fluid from the water absorption port to the discharge port via the pump chamber.

In the present invention, the elastic member is annular, and it is desirable that the annular portion is provided with an annular elastic member accommodating recess for accommodating the elastic member on a surface facing the impeller. In this way, the elastic member can prevent or suppress the disturbance of the water flow generated by the impeller. Further, it is easy to prevent the elastic member from falling off from the partition wall member due to the water flow generated by the impeller.

In the present invention, the elastic member may be annular and may be fixed to the shaft portion by passing the shaft portion of the rotor through the center hole thereof. In this way, it is easy to fix the elastic member to the rotor. Further, even when the rotor rotates, it is possible to prevent the elastic member from falling off from the rotor.

In the present invention, a gap may be provided between the impeller and the elastic member in the axial direction. By providing such a gap, it is possible to prevent or suppress the elastic member fixed to the rotor from disturbing the water flow generated by the impeller.

In the present invention, a case body having a recess for accommodating an impeller, a case having a water suction port communicating with the recess, and a discharge port communicating with the recess, and a case covered with the case from the axial direction and the pump together with the case. The partition wall member has a partition wall member for partitioning a chamber, and the partition wall member has an annular portion facing the impeller from the side opposite to the case body in the axial direction, and an axial line from an end edge on the inner peripheral side of the annular portion. A tubular portion that extends in the direction and surrounds the magnet from the outer peripheral side, and a sealing portion that seals the end portion of the tubular portion on the side opposite to the annular portion, and the elastic member is provided on the inner peripheral surface of the recess. It can be fixed. In this way, it is easy to prevent the case from being damaged when the fluid freezes.

In the present invention, the case body is provided with an elastic member accommodating recess for accommodating the elastic member on the bottom surface or the peripheral wall surface of the recess, and the elastic member is accommodated in the elastic member accommodating recess. Can be. In this way, the elastic member can prevent or suppress the disturbance of the water flow generated by the impeller.

The bottom surface of the recess is provided with an opening of the water suction port on the pump chamber side and an annular recess for accommodating the elastic member that surrounds the opening. The elastic member is annular and said. It may be accommodated in the elastic member accommodating recess. Near the bottom surface of the recess provided in the case, an opening of a water suction port through which a fluid flows is provided. Therefore, the vicinity of the bottom surface of the recess in the case is easily affected by the external environment and is easily frozen at a low temperature. Therefore, if the elastic member is arranged in the elastic member accommodating recess surrounding the opening on the bottom surface of the recess, it is possible to prevent or suppress the case from being damaged when the fluid staying in the vicinity of the bottom surface of the recess freezes.

In the present invention, the elastic member can be a closed cell foam.

In the pump device of the present invention, an elastic member is arranged at a position close to the impeller in the pump chamber. Therefore, at the time of freezing, the capacity of the pump chamber can be expanded around the impeller in which the space where the fluid exists in the pump chamber is large. Therefore, damage to the impeller can be prevented or suppressed.

It is external perspective view of the pump device of Example 1. FIG. It is sectional drawing of the pump device of Example 1. FIG. It is an exploded perspective view of the pump device of Example 1. FIG. It is a perspective view of a rotor. It is a perspective view of a case. It is an exploded perspective view of a partition wall member and an elastic member. It is sectional drawing of the pump device of Example 2. FIG. It is a perspective view of the rotor of the pump device of Example 2. FIG. It is sectional drawing of the pump device of Example 3. FIG. It is an exploded perspective view of the case of the pump device of Example 3 and an elastic member.

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

(Example 1)
FIG. 1 is an external perspective view of the pump device of the first embodiment. FIG. 2 is a cross-sectional view of the pump device of the first embodiment. FIG. 3 is an exploded perspective view of the pump device of the first embodiment. The pump device 1A of this example 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 1A includes a rotor 2 and a pump chamber 3 for accommodating the rotor 2. Further, the pump device 1A includes a casing 4 for partitioning the pump chamber 3. Further, the pump device 1A includes a motor mechanism unit 5 for rotating the rotor 2. As shown in FIG. 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 X along the axis L of the shaft portion 12. The axis L of the shaft portion 12 coincides with the rotation center axis of the impeller 11. As shown in FIGS. 1 and 2, the casing 4 includes a case 15 and a partition wall member 16. The case 15 and the partition wall member 16 are overlapped in the axial direction X.

As shown in FIGS. 2 and 3, the motor mechanism portion 5 includes a stator 17 that surrounds the magnet 13 from the radial outside 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 1A includes a circuit board 21 to which the end of the winding of the coil 19 is connected, a resin sealing member 22 that covers the stator 17 and the circuit board 21, and a metal member fixed to the resin sealing member 22. 23 and. The resin sealing member 22 constitutes a part of the exterior of the pump device 1A.

Further, the pump device 1A includes an elastic member 25 arranged in the pump chamber 3. In the following description, the side where the impeller 11 is located in the axial direction X is referred to as the first direction X1, and the side where the magnet 13 is located is referred to as the second direction X2.

(Rotor)
FIG. 4 is a perspective view of the rotor 2 as viewed from the first direction X1. The impeller 11 has a first annular plate portion 31 having an annular shape when viewed from the axial direction X, and an annular second annular plate portion 32 located in the second direction X2 of the first annular plate portion 31. A plurality of blades 33 provided between the first annular plate portion 31 and the second annular plate portion 32 are provided. The first annular plate portion 31 is slightly inclined in the second direction X2 from the inner peripheral side to the outer peripheral side. Further, the first annular plate portion 31 includes an annular protrusion 31a projecting from the inner peripheral side edge in the first direction X1. The second annular plate portion 32 overlaps with the first annular plate portion 31 when viewed from the axial direction X. The blade 33 has a rib-like shape, and extends between the first annular plate portion 31 and the second annular plate portion 32 by bending forward in the rotation direction R from the inner peripheral side toward the outer peripheral side. In this example, each blade 33 is provided as a rib protruding from the second annular plate portion 32 material in the first direction X1. The first annular plate portion 31 is connected to the end portion of each blade 33 in the first direction X1 by ultrasonic welding.

The shaft portion 12 has a tubular shape and extends in the second direction X2 from the end edge on the inner peripheral side of the second annular plate portion 32. As shown in FIG. 2, a sleeve 35, which is a sliding bearing, is fixed inside the shaft hole 12a of the shaft portion 12. Further, the shaft portion 12 includes a flange portion 36 protruding from the middle of the axial direction X toward the outer peripheral side. As shown in FIG. 4, in the shaft portion 12, the magnet 13 is fixed to the region of the flange portion 36 in the second direction X2. The magnet 13 has an annular shape and is fixed to the outer peripheral surface of the shaft portion 12. The magnet 13 is magnetized with S poles and N poles alternately in the circumferential direction.

Here, as shown in FIG. 2, 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 X. The end portion of the support shaft 40 in the first direction X1 is supported by the case 15, and the end portion of the second direction X2 is supported by the partition member 16.

(casing)
FIG. 5 is a perspective view of the case 15 when viewed from the second direction X2. FIG. 6 is an exploded perspective view of the partition wall member 16 and the elastic member 25. As shown in FIG. 5, the case 15 includes a case main body 42 having a recess 41 for accommodating the impeller 11, a water absorption port 43 communicating with the recess 41, and a discharge port 44 communicating with the recess 41. The bottom surface 41a of the recess 41 in the case body 42 is circular. At the center of the bottom surface 41a, a first opening 45 (opening) on the pump chamber 3 side of the water suction port 43 is provided. As shown in FIG. 1, the water absorption port 43 extends coaxially with the axis L of the rotor 2. That is, the water supply pipe 43 extends from the case main body 42 in the first direction X1. The peripheral wall surface 41b of the recess 41 in the case body 42 has an annular shape. A second opening 46 on the pump chamber 3 side of the discharge port 44 is provided in a part of the peripheral wall surface 41b in the circumferential direction. The discharge port 44 extends from the case body 42 to the outer peripheral side.

An annular recess 46a surrounding the first opening 45 is provided on the bottom surface 41a of the recess 41. Further, on the bottom surface 41a of the recess 41, an annular step portion 46b is provided on the inner peripheral side of the annular recess 46a. The annular step portion 46b is recessed from the bottom surface 41a in the first direction X1. The inner peripheral end of the annular step portion 46b is continuous with the first opening 45. A cylindrical case-side rotor support portion 47 is provided at a position of the case body 42 at a position separated from the bottom surface 41a of the recess 41 in the second direction X2. The case-side rotor support portion 47 is located in front of the inflow direction of the fluid flowing in from the water suction port 43. The case-side rotor support portion 47 is formed by three legs 48 protruding in the second direction X2 from the inner peripheral wall of the first opening 45 in the case body 42, that is, the inner wall surface portion of the water suction port 43 on the pump chamber 3 side. It is supported.

Here, as shown in FIG. 2, the end portion of the support shaft 40 projecting from the sleeve 35 of the rotor 2 toward the case 15 is inserted into the case-side rotor support portion 47 in the first direction X1. A washer 50 is arranged between the sleeve 35 and the case-side rotor support portion 47.

Next, as shown in FIGS. 2 and 6, the partition member 16 accommodates the magnet 13 and the blade 33 of the rotor 2 as an integral structure in the pump chamber 3 and shields the fluid. , The annular portion 51 facing the impeller 11 from the second direction X2, the tubular portion 52 extending from the inner peripheral side edge of the annular portion 51 in the second direction X2 and surrounding the magnet 13 from the outer peripheral side, and the tubular portion 52. A sealing portion 53, which seals the end portion of the two directions X2, is provided. The annular portion 51 faces the bottom surface 41a of the recess 41 of the case body 42 via the impeller 11. Further, the partition wall member 16 includes an outer tubular portion 54 extending in the second direction X2 from the outer peripheral edge of the annular portion 51 and an annular flange portion 55 extending radially outward from the outer tubular portion 54. In the partition member 16, the flange portion 55 abuts on the outer peripheral side portion of the recess 41 in the case body 42 from the second direction X2, and the outer cylinder portion 54 and the annular portion 51 are fitted into the recess 41. Here, an annular step portion 57 is provided at the opening edge portion of the recess 41 in the case body 42. 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 cylinder portion 54.

In the annular portion 51, the facing surface 51a facing the impeller 11 is provided with an annular elastic member accommodating recess 60 for accommodating the elastic member 25. The elastic member accommodating recess 60 is provided concentrically with the tubular portion 52.

The elastic member 25 is annular. The elastic member 25 is housed in the elastic member accommodating recess 60 and fixed to the partition wall member 16. The cross-sectional shape of the elastic member 25 cut along a plane parallel to the axis L is rectangular.

The elastic member 25 is a closed cell foam. In this example, it is EPDM (ethylene propylene diene rubber). As the elastic member 25, Teflon (registered trademark), nitrile rubber, or the like can also be used. 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. Here, the elastic member 25 has a size that can absorb the volume integral of the fluid that increases due to freezing when the fluid in the pump chamber 3 freezes due to elastic deformation. In this example, the elastic member 25 can be elastically deformed by a volume integral or more corresponding to 10% of the volume of the pump chamber 3 when the elastic member 25 changes from the natural state to the compressed state.

The blocking portion 53 has a disk shape. As shown in FIG. 2, the blocking portion 53 includes a partition wall member-side rotor support portion 62 projecting in the first direction X1 at a central portion overlapping the axis L. The partition wall member side rotor support portion 62 has a cylindrical shape, and has an end surface perpendicular to the axis L in the first direction X1. Further, the partition wall member side rotor support portion 62 is provided with a support shaft fixing recess 63 at the center of the end surface in the first direction X1. The end portion of the support shaft 40 in the second direction X2 is inserted into the support shaft fixing recess 63 and fixed.

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 second direction X2. 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 in the first direction X1 of the bulkhead member side rotor support portion 62. When the pump device 1A operates and the impeller 11 rotates, the rotor 2 is displaced in the first direction X1 and between the end surface of the bulkhead member side rotor support portion 62 in the first direction X1 and the sleeve 35. , A gap is formed.

Here, the inner peripheral surface (bottom surface 41a and peripheral wall surface 41b) of the recess 41 of the case body 42, the facing surface 51a of the annular portion 51 of the partition wall member 16, the inner peripheral surface of the tubular portion 52, and the first direction of the sealing portion 53. The end face of X1 constitutes the inner wall surface 3a of the pump chamber 3.

(Stator)
As shown in FIGS. 2 and 3, the stator 17 is arranged on the outer peripheral side of the tubular portion 52 of the partition wall member 16. As shown in FIG. 3, the stator 17 includes a stator core 18 having a plurality of cores 65 arranged in an annular shape. As shown in FIG. 2, each core 65 includes a salient pole 67 extending in the radial direction. Further, the stator 17 includes a plurality of coils 19 wound around the salient poles 67 of each core 65 via an insulator. The end surface of each salient pole 67 on the inner peripheral side is in contact with the outer peripheral surface of the tubular portion 52. The end surface of the salient pole 67 on the inner peripheral side faces the magnet 13 of the rotor 2 in the radial direction via the tubular portion 52. In this example, the motor mechanism unit 5 is a three-phase brushless motor. That is, in this example, nine cores 65 are provided, and the nine coils 19 wound around the salient poles 67 of each core 65 are three U-phase coils 19 and three V-phase coils 19. It constitutes three W-phase coils 19. 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 FIGS. 2 and 3, a circuit board 21 is arranged in the second direction X2 of the blocking portion 53. The end of the winding of 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. A metal member 23 is arranged in the second direction X2 of the circuit board 21. The stator 17 and the circuit board 21 are covered with a resin sealing member 22. The resin sealing member 22 is a BMC (Bulk Molding Compound) which is a thermosetting resin material.

A metal member 23 is fixed to the end surface of the resin sealing member 22 in the second direction X2. The metal member 23 is a reinforcing member that reinforces the resin sealing member 22. The metal member 23 has a disk shape and is provided with screw holes 23a at four locations around the axis L 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 1A. Here, as shown in FIG. 3, the case 15 is provided with case-side through holes 15a penetrating in the axial direction X 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 X 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 X at four locations in the circumferential direction. The case 15 penetrates the case-side through hole 15a, the resin-sealing member 22-side through hole, and the resin-sealing member-side through hole 22a in the axial direction X, and is screwed into the screw hole 23a of the metal member 23. It is fixed to the partition member 16 by the screw 69 of the head.

When driving the pump device 1A, 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 suction port 43, and the fluid is discharged from the discharge port 44.

(Action effect)
The pump device 1A of this example includes an elastic member 25 in the pump chamber 3. Further, the elastic member 25 is fixed to the inner wall surface portion (opposing surface 51a of the annular portion 51 of the partition wall member 16) facing the impeller 11 on the inner wall surface 3a of the pump chamber 3. Therefore, when the volume of the fluid remaining in the pump chamber 3 increases due to freezing, 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 pump chamber 3 has a large space. Capacity expands. As a result, the pressure applied to the impeller 11 from the fluid whose volume has increased can be reduced, so that damage to the impeller 11 can be avoided. For example, when pressure is applied to the impeller 11 from the fluid whose volume has increased, damage such as peeling of the welded portion between the blade 33 and the first annular plate portion 31 may occur. It can be avoided. Further, since the pressure applied to the inner wall surface of the pump chamber 3 can be reduced from the fluid whose volume has increased, it is possible to prevent the pump chamber 3 from being damaged.

Further, in this example, the partition wall member 16 includes an annular portion 51 facing the impeller 11 from the side opposite to the case main body 42 in the axial direction X, and the elastic member 25 is fixed to the annular portion 51. If the elastic member 25 is arranged at such a position, it is possible to prevent the elastic member 25 from obstructing the flow of the fluid from the water absorption port 43 to the discharge port 44 via the pump chamber 3.

Further, the elastic member 25 is annular, and the annular portion 51 includes an annular elastic member accommodating recess 60 for accommodating the elastic member 25 on the facing surface 51a facing the impeller 11. Therefore, the elastic member 25 can prevent or suppress the disturbance of the water flow generated by the impeller 11. Further, it is possible to prevent the elastic member 25 from falling off from the partition wall member 16 due to the water flow generated by the impeller 11.

Here, when the elastic member 25 changes from the natural state to the compressed state, the elastic member 25 can be elastically deformed by a volume integral or more corresponding to 10% of the volume of the pump chamber 3. Therefore, the pressure applied to the impeller 11 from the fluid whose volume has increased and the pressure applied to the inner wall surface of the pump chamber 3 from the fluid whose volume has increased can be reliably reduced.

(Example 2)
FIG. 7 is a cross-sectional view of the pump device 1B of the second embodiment. FIG. 8 is a perspective view of the rotor 2 of the pump device 1B of the second embodiment. In the pump device 1B of this example, the position of the elastic member 25 arranged in the pump chamber 3 is different from that of the pump device 1A described above. That is, in this example, the elastic member 25 is fixed to the rotor 2 arranged in the pump chamber 3. Therefore, in this example, the annular portion 51 of the partition wall member 16 is not provided with the elastic member accommodating recess 60, and the elastic member 25 is not fixed to the partition wall member 52.

Here, since the pump device 1B of the second embodiment has the same configuration as the pump device 1B described above, the corresponding portions are designated by the same reference numerals. Further, the rotor 2 and the elastic member 25 will be described, and the description of other configurations will be omitted.

(Rotor)
As shown in FIG. 8, the impeller 11 has a first annular plate portion 31 having an annular shape when viewed from the axial direction X, and an annular first annular plate portion 31 located in the second direction X2 of the first annular plate portion 31. The two annular plate portion 32 and a plurality of blades 33 provided between the first annular plate portion 31 and the second annular plate portion 32 are provided. The shaft portion 12 has a tubular shape and extends in the second direction X2 from the end edge on the inner peripheral side of the second annular plate portion 32. A sleeve 35, which is a sliding bearing, is fixed inside the shaft hole 12a of the shaft portion 12. Further, the shaft portion 12 includes a flange portion 36 protruding from the middle of the axial direction X toward the outer peripheral side. In the shaft portion 12, an annular magnet 13 is fixed to the region of the flange portion 36 in the second direction X2.

In the shaft portion 12, the elastic member 25 is fixed to the impeller 11 side of the collar portion 36. The elastic member 25 is annular, and the cross-sectional shape cut along the plane parallel to the axis L is rectangular. The shaft portion 12 is passed through the center hole between the magnet 13 and the impeller 11 in the axial direction X. The elastic member 25 is in close contact with the outer peripheral surface of the shaft portion 12. Further, the elastic member 25 is fixed to the shaft portion 12 with an adhesive or the like. In the axial direction X, the elastic member 25 and the impeller 11 are separated from each other. That is, a gap G is provided between the impeller 11 and the elastic member 25 in the axial direction X.

The elastic member 25 is a closed cell foam. The end face of the elastic member 25 in the first direction X1, the outer peripheral surface on the outer side in the radial direction, and the end face in the second direction X2 are smooth surfaces on which air bubbles are not exposed. When the elastic member 25 changes from the natural state to the compressed state, the elastic member 25 can be elastically deformed by a volume integral or more corresponding to 10% of the volume of the pump chamber 3.

(Action effect)
The pump device 1B of this example includes an elastic member 25 in the pump chamber 3. Further, the elastic member 25 is arranged between the impeller 11 and the magnet 13 on the inner wall surface of the pump chamber 3, and is close to the impeller 11. Therefore, when the volume of the fluid remaining in the pump chamber 3 increases due to freezing, 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 pump chamber 3 has a large space. Capacity expands. As a result, the pressure applied to the impeller 11 from the fluid whose volume has increased can be reduced, so that damage to the impeller 11 can be avoided. Further, since the pressure applied to the inner wall surface of the pump chamber 3 from the fluid whose volume has increased can be reduced, damage to the pump chamber 3, that is, damage to the casing 4 can be avoided.

Further, the elastic member 25 has an annular shape, and the shaft portion 12 of the rotor 2 is passed through the center hole thereof and fixed to the shaft portion 12. Therefore, it is easy to fix the elastic member 25 to the rotor 2. Further, even when the rotor 2 rotates, it is possible to prevent the elastic member 25 from falling off from the rotor 2.

Further, in this example, a gap G is provided between the impeller 11 and the elastic member 25 in the axial direction X. Therefore, the elastic member 25 fixed to the rotor 2 can prevent or suppress the disturbance of the water flow generated by the impeller 11.

(Example 3)
FIG. 9 is a cross-sectional view of the pump device 1C of the third embodiment. FIG. 10 is a perspective view of the case 15 and the elastic member 25 of the pump device 1C of the third embodiment when viewed from the second direction X2. In the pump device 1C of this example, the position of the elastic member 25 arranged in the pump chamber 3 is different from that of the pump devices 1A and 1B described above. That is, in this example, the elastic member 25 is fixed to the inner peripheral surface of the recess 41 of the case 15. Therefore, in this example, the annular portion 51 of the partition wall member 16 is not provided with the elastic member accommodating recess 60, and the elastic member 25 is not fixed to the partition wall member 52. Further, the elastic member 25 is not fixed to the rotor 2.

Here, since the pump device 1C of the third embodiment has the same configuration as the pump device 1C described above, the corresponding portions are designated by the same reference numerals. Further, the case 15 and the elastic member 25 will be described, and the description of other configurations will be omitted.

(Case)
As shown in FIG. 10, the case 15 includes a case main body 42 having a recess 41 for accommodating the impeller 11, a water absorption port 43 communicating with the recess 41, and a discharge port 44 communicating with the recess 41. The bottom surface 41a of the recess 41 in the case body 42 is circular. At the center of the bottom surface 41a, a first opening 45 (opening) on the pump chamber 3 side of the water suction port 43 is provided. The water suction port 43 extends coaxially with the axis L of the rotor 2. It extends from the case body 42 in the first direction X1. The peripheral wall surface 41b of the recess 41 in the case body 42 has an annular shape. A second opening 46 on the pump chamber 3 side of the discharge port 44 is provided in a part of the peripheral wall surface 41b in the circumferential direction. The discharge port 44 extends from the case body 42 to the outer peripheral side.

An annular elastic member accommodating recess 60 is provided on the bottom surface 41a of the recess 41 in the case 15. The elastic member accommodating recess 60 is an annular groove that concentrically surrounds the opening of the water suction port 43 on the pump chamber 3 side. Here, the elastic member 25 has an annular shape, is housed in the elastic member accommodating recess 60, and is fixed to the case 15. The cross-sectional shape of the elastic member 25 cut along a plane parallel to the axis L is rectangular. The end surface of the elastic member 25 in the second direction X2 does not protrude toward the impeller 11 from the bottom surface 41a of the recess 41 of the case 15.

The elastic member 25 is a closed cell foam. In the elastic member 25, the end surface of the second direction X2 facing the impeller 11 is a smooth surface on which air bubbles are not exposed. When the elastic member 25 changes from the natural state to the compressed state, the elastic member 25 can be elastically deformed by a volume integral or more corresponding to 10% of the volume of the pump chamber 3.

A cylindrical case-side rotor support portion 47 is provided at a position of the case body 42 at a position separated from the bottom surface 41a of the recess 41 in the second direction X2. The case-side rotor support portion 47 is supported by three legs 48 protruding in the first direction X1 from the inner peripheral wall of the first opening 45 in the case body 42, that is, the inner wall surface portion of the water absorption port 43 on the pump chamber side. Has been done.

(Action effect)
The pump device 1C of this example includes an elastic member 25 in the pump chamber 3. Further, the elastic member 25 is fixed to the inner wall surface portion (bottom surface 41a of the recess 41 of the case 15) facing the impeller 11 on the inner wall surface of the pump chamber 3. Therefore, when the volume of the fluid remaining in the pump chamber 3 increases due to freezing, 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 pump chamber 3 has a large space. Capacity expands. As a result, the pressure applied to the impeller 11 from the fluid whose volume has increased can be reduced, so that damage to the impeller 11 can be avoided. Further, since the pressure applied to the inner wall surface of the pump chamber 3 from the fluid whose volume has increased can be reduced, damage to the pump chamber 3, that is, damage to the casing 4 can be avoided.

Further, in the vicinity of the bottom surface 41a of the recess 41 provided in the case 15, an opening of a water absorption port 43 into which a fluid flows is provided. Therefore, in the vicinity of the bottom surface 41a of the recess 41 of the case 15, it is easily affected by the external environment and easily freezes at a low temperature. On the other hand, in this example, the elastic member 25 is arranged in the elastic member accommodating recess 60 surrounding the first opening 45 of the bottom surface 41a of the recess 41. Therefore, it is possible to prevent the case 15 from being damaged when the fluid staying in the vicinity of the bottom surface 41a of the recess 41 freezes.

(Modification example)
The elastic member 25 may be fixed to the peripheral wall surface 41b of the recess 41 of the case 15. In this case, the elastic member accommodating recess 60 extending in the circumferential direction is provided on the peripheral wall surface 41b of the recess 41 in the case 15, and the elastic member 25 is accommodated in the elastic member accommodating recess 60. Even in this way, since the capacity of the pump chamber 3 can be expanded around the impeller 11, damage to the impeller 11 can be avoided. In addition, damage to the pump chamber 3 can be avoided.

Further, a plurality of elastic members 25 may be arranged in the pump chamber 3. That is, the elastic member 25 may be provided in the case 15 and the partition wall member 16. Further, the elastic member 25 may be provided in the case 15 and the rotor 2. Further, the elastic member 25 may be provided on the partition member 16 and the rotor 2. Further, the elastic member 25 may be provided in the case 15, the partition wall member 16, and the rotor 2.

1A, 1B, 1C ... Pump device, 2 ... Rotor, 3 ... Pump chamber, 4 ... Casing, 5 ... Motor mechanism, 11 ... Impeller, 12 ... Shaft, 12a ... Shaft hole, 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 ... sealing member side Through hole, 23 ... metal member, 23a ... screw hole, 25 ... elastic member, 31 ... first annular plate portion, 31a ... annular protrusion, 32 ... second annular plate portion, 33 ... blade, 35 ... sleeve, 36 ... Flange, 40 ... Support shaft, 41 ... Recess, 41a ... Bottom surface, 41b ... Circumferential wall surface, 42 ... Case body, 43 ... Water inlet, 44 ... Discharge port, 45 ... First opening, 46a ... Circular groove, 46b ... Circular Step part, 47 ... Case side rotor support part, 48 ... Three legs, 51 ... Annular part, 51a ... Facing surface, 52 ... Cylinder part, 53 ... Sealing part, 54 ... Outer cylinder part, 55 ... Flange part, 57 ... Steps, 58 ... O-rings, 60 ... Elastic member accommodating recesses, 62 ... Bulkhead member side rotor support, 63 ... Support shaft fixing recesses, 65 ... Cores, 67 ... salient poles, 68 ... Connector, 69 ... Headed screw, L ... axis, X ... axis direction, X1 ... first direction, X2 ... second direction

Claims (9)

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 pump chamber that houses the rotor and
Have,
A pump device characterized in that an elastic member is fixed to at least one of an inner wall surface portion facing the impeller on the inner wall surface of the pump chamber and between the impeller and the magnet in the rotor. A case body having a recess for accommodating an impeller, a case having a water suction port communicating with the recess, and a case having a discharge port communicating with the recess.
It has a partition member that covers the case from the axial direction and partitions the pump chamber together with the case.
The partition wall member includes an annular portion facing the impeller from the side opposite to the case body, a tubular portion extending in the axial direction from the inner peripheral edge of the annular portion and surrounding the magnet from the outer peripheral side, and the above. A sealing portion, which seals the end portion of the tubular portion opposite to the annular portion, is provided.
The pump device according to claim 1, wherein the elastic member is fixed to the annular portion. The elastic member is annular and has an annular shape.
The pump device according to claim 2, wherein the annular portion is provided with an annular elastic member accommodating recess for accommodating the elastic member on a surface facing the impeller. The pump device according to claim 1, wherein the elastic member has an annular shape, and the shaft portion of the rotor is passed through the center hole thereof and fixed to the shaft portion. The pump device according to claim 4, wherein a gap is provided between the impeller and the elastic member in the axial direction. A case body having a recess for accommodating an impeller, a case having a water suction port communicating with the recess, and a case having a discharge port communicating with the recess.
It has a partition member that covers the case from the axial direction and partitions the pump chamber together with the case.
The partition wall member is an annular portion that faces the impeller from the side opposite to the case body in the axial direction, and a cylinder that extends in the axial direction from the inner peripheral edge of the annular portion and surrounds the magnet from the outer peripheral side. A portion and a sealing portion for sealing the end portion of the tubular portion opposite to the annular portion.
The pump device according to claim 1, wherein the elastic member is fixed to the inner peripheral surface of the recess. The case body is provided with an elastic member accommodating recess for accommodating the elastic member on the bottom surface or the peripheral wall surface of the recess.
The pump device according to claim 6, wherein the elastic member is housed in the elastic member accommodating recess. The bottom surface of the recess is provided with an opening of the water suction port on the pump chamber side and an annular recess for accommodating the elastic member that surrounds the opening.
The pump device according to claim 7, wherein the elastic member is annular and is housed in the elastic member accommodating recess. The pump device according to any one of claims 1 to 8, wherein the elastic member is a closed cell foam.

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