JP2005061391A - Pump device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a pump device provided with a fluid passage through which a fluid is pressurized and sent for lubrication or cooling and which is constituted with good space efficiency. <P>SOLUTION: A pump device includes a pump housing 11 including a fluid chamber 15 for inhaling the fluid flowing through the fluid chamber 15 via an intake port 11a and discharging the fluid to an outside via a discharge port 15c, a motor housing 12 including a shaft whose one end projects into the pump housing and to which an impeller is assembled and whose the other end is rotatably supported within the motor housing, and a bearing plate 13 disposed between the pump housing 11 and the motor housing 12 and provided with a bearing part rotatably supporting the shaft 21. The fluid passage 31 is formed in the bearing plate 13 to lead the fluid from the fluid chamber 15b to the outer periphery of the shaft 21, and is provided with an opening facing the fluid chamber 15b. Further, the opening communicates with the bearing part 16a. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a pump device that rotates an impeller by driving a motor and pumps fluid, and particularly relates to a structure of a pump device that prevents foreign matter from being mixed around a shaft that rotates the impeller.

  2. Description of the Related Art Conventionally, a pump device is used to cool and lubricate a predetermined portion by circulating a fluid to be cooled or lubricated from a suction port in a closed loop circulation path using rotation of an impeller. Such a pump device includes an impeller in a casing, and the impeller is supported by the casing so as to be rotatable by a shaft. A pump device is known that supplies fluid to the discharge side using the rotation of an impeller and circulates fluid in a circulation path (Patent Document 1).

In the device disclosed in Patent Document 1, a shaft that supports an impeller is rotatably supported by a bearing portion formed in a casing. The discharge side and the bearing portion are connected by piping outside the casing so that the fluid having a high pressure on the discharge side can be supplied to the bearing portion. A part of the fluid is supplied.
Japanese Patent Laid-Open No. 7-217593 (see page 1, FIG. 1)

  However, in the configuration shown in Patent Document 1 described above, the discharge side and the bearing portion are connected by piping outside the casing, and a part of the fluid that has become a high pressure on the discharge side with respect to the bearing portion that pivotally supports the impeller. Must be supplied. For this reason, piping for guiding the fluid to the bearing portion is required outside the casing, and an increase in size of the pump device is inevitable.

  In addition, when foreign matter or the like is mixed in the fluid, the gap between the bearing and the shaft is made with high precision so that no play occurs when the impeller rotates. For this reason, when a foreign material mixes into the bearing portion, the foreign material may be caught in the gap. When the foreign matter is caught, the caught foreign matter is not easily discharged from the gap of the bearing portion. This causes a problem in the bearing portion and deteriorates the life of the pump device.

  Therefore, the present invention has been made in view of the above-described problems, and it is possible to provide a pump device that can be downsized without the need for piping outside the device as in the prior art, to prevent foreign matters from being mixed in, and a bearing portion. It is an object of the present invention to provide a pump device that protects the water.

  The first means taken in order to solve the above-described problem is that a fluid chamber is formed inside, a pump housing that sucks fluid flowing through the fluid chamber from the suction port, and discharges the fluid from the discharge port to the outside. A motor housing having a stator, one end projecting into the pump housing, an impeller is attached, the other end is rotatably supported in the motor housing, and the shaft is attached to the shaft so as to face the stator A pump device comprising: a magnet to be disposed; and a bearing plate that is disposed between the pump housing and the motor housing and has a bearing portion that rotatably supports the shaft. A first flow path for guiding fluid from the fluid chamber to the periphery of the shaft is formed therein, and the first flow path includes an opening facing the fluid chamber. And summarized in that has a structure for connecting between the opening and the bearing portion.

  Preferably, the opening may be formed in a high pressure portion where the pressure of the fluid becomes high in the pump housing.

  Moreover, it is good to provide a filter in the opening.

  In the second means taken to solve the above problems, a fluid chamber is formed inside, a pump housing that sucks fluid flowing through the fluid chamber from the suction port, and discharges the fluid from the discharge port to the outside. A motor housing having a stator, one end projecting into the pump housing, an impeller is attached, the other end is rotatably supported in the motor housing, and the shaft is attached to the shaft so as to face the stator In the pump device including the magnet to be disposed, the impeller has a second flow path formed in a radial direction, and communicates with the second flow path to guide the fluid to the end of the shaft. Is formed on the shaft, and a filter is provided at the inlet for introducing the fluid in the second flow path.

  Preferably, the second flow path is formed in a base portion that supports the blade of the impeller.

  According to the first aspect of the present invention, since the first flow path for guiding the fluid from the fluid chamber to the periphery of the shaft is formed inside the bearing plate, the fluid is supplied to the outside of the pump device with respect to the bearing portion. Leading piping is no longer necessary. For example, the pump device as a whole can be downsized as compared with the case where similar flow paths are provided along the outside of the motor housing. Therefore, in order to perform lubrication or cooling, a flow path for pumping a fluid to a required portion in the motor can be formed inside the apparatus, and the space can be configured efficiently.

  According to the second aspect of the present invention, if the opening faces the high-pressure portion in the pump housing, the shaft and the motor side can be lubricated or cooled by using a part of the high-pressure fluid. .

  According to the invention described in claim 3, by providing the filter in the opening, it is possible to prevent foreign matter from the fluid chamber around the shaft by the filter provided in the opening. Can be prevented.

  According to the invention described in claim 4, the impeller is formed with the second flow path for guiding the fluid to the inner diameter in the radial direction. In addition, when a third flow path is formed in the shaft that communicates with the second flow path and guides the fluid to the end of the shaft, the fluid passes through the second flow path and the third flow path and passes through the end of the shaft. Therefore, it is possible to efficiently cool or circulate around the shaft. In this case, since the filter is provided at the inlet of the second flow path for introducing the fluid, the fluid is guided to the inner diameter of the impeller through the filter provided at the inlet of the second flow path of the impeller, The third fluid reaches the end of the shaft. At this time, since a filter is provided at the fluid inlet of the second flow path, foreign matter is collected by this filter. In addition, since the filter is provided on the outer diameter with the impeller, even if there is a foreign object on the outer diameter, the foreign object is repelled outside the impeller by centrifugal force without adhering to the filter due to the rotation of the impeller. There is no accumulation of foreign matter on the surface. For this reason, protection of the bearing part of the shaft which rotates an impeller can be performed by simple structure.

  In this case, when the second flow path is formed in the base portion that supports the blade of the impeller, the bearing portion can be advantageously protected in terms of space by using the base portion that does not have a mechanism for moving the fluid.

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

(First embodiment)
FIG. 1 is a cross-sectional view illustrating a configuration of a pump device 10 according to the first embodiment. The pump device 10 shown here is applied to a vehicle as an example. The pump device 10 circulates fluid (here, cooling water) between an engine and a radiator (not shown) in an engine room of the vehicle. The present invention can be applied to a water pump or an oil pump that supplies a fluid (in this case, oil) for lubrication to an engine, and is driven electrically.

  The pump device 10 has an outer shape formed of a pump housing 11 made of metal and a motor housing 12 made of resin. The pump housing 11 includes a fluid chamber 15 to which a fluid is supplied, a suction port 11 a that sucks the fluid flowing in the fluid chamber 15, and a discharge port that discharges the fluid in the fluid chamber 15 to the outside of the pump device 10 at a high pressure. 15c. The pump housing 11 is formed with an opening for introducing a part of the fluid into a portion (high pressure portion) 32 where the fluid on the side opposite to the suction port 11a becomes high pressure. A resin bearing plate 13 is disposed between the pump housing 11 and the motor housing 12, and is disposed so as to cover the opening from the axial direction. And the sealing performance is ensured by the pump housing 11 and the bearing plate 13.

  The bearing plate 13 is formed with a bearing hole 13a and a bearing portion 13b having a smaller diameter than the bearing hole 13a in the center in the radial direction. A shaft 21 having a large diameter portion and a small diameter portion is inserted through the bearing hole 13a from the axial direction, and the small diameter portion of the shaft 21 is rotatably supported by the bearing portion 13b. The fluid chamber 15 formed inside the housing protrudes in the center.

  The shaft 21 is a member of a motor 20 (described later) provided on the opposite side across the fluid chamber 15 and the bearing plate 13, and one end on the motor side is a recess formed in the center of the motor housing 12. An impeller 16 is attached to the other end on the pump side that is rotatably supported and protrudes into the fluid chamber 15 by press-fitting. The impeller 16 has a substantially circular shape when viewed from the suction port 11a side, and a plurality of blades 16a are integrally formed on the outer diameter thereof in the circumferential direction.

  The fluid chamber 15 has an outer diameter that is greater than the first fluid chamber 15a that is continuous with the cylindrical suction port 11a and the first fluid chamber 15a that is higher in pressure than the first fluid chamber 15a when the pump device 10 is operated. The second fluid chamber 15b (high pressure part) formed in the above is formed. In this case, the discharge port 15c that discharges the fluid is a plane orthogonal to the suction port 11a that sucks the fluid, and is formed at a portion where the fluid is discharged at a high pressure by the rotation of the impeller 16.

  Next, the configuration of the motor 20 will be described. In the motor 20, a recess is formed in the motor housing 12, and a core 24 in which a plurality of annular laminated plates made of metal are stacked is disposed in the recess. The coil 24 is wound around the core 24, the core 24 around which the coil 23 is wound is provided in the recess, and the stator of the motor 20 is formed. The recess surface of the stator is molded with resin. ing.

  The shaft 21 is made of a columnar metal, and small diameter portions 21a and 21c having the same diameter are formed at both ends, and a large diameter portion 21b is integrally formed therebetween. The large diameter portion 21b is opposed to the inner diameter of the annular core 24 with a predetermined interval, and a cylindrical magnet 22 is attached to the large diameter portion 21b. The magnet 22 is a four-pole magnet in which N poles and S poles are alternately arranged along the circumferential direction on the outer periphery of the large-diameter portion 21b of the shaft 21, and the magnet 22 is an adhesive with respect to the large-diameter portion 21b. Alternatively, the magnet 22 is fixed by adhesive means such as a strong tape, and the magnet 22 is configured to rotate integrally with the shaft 21.

  In the shaft 21, a small diameter portion 21 c is rotatably supported by a bearing portion 12 b formed in the center of the concave portion of the motor housing 12, and the other small diameter portion 21 a passes through the bearing hole 13 a of the bearing plate 13, and the fluid chamber 15. The impeller 16 is attached to the protruding tip. In this case, a bushing is inserted into the bearing portion 12b formed at the center of the recess of the motor housing 12 so that the shaft 21 is coaxial with the bearing portion 13b of the bearing plate 13 and the shaft 21 rotates smoothly. It should be molded.

  Next, the flow path through which the fluid flows will be described. A gap 12t exists between the inner wall 12a of the motor housing 12 and the end portion of the magnet 22 in the axial direction. A slit-shaped gap 12s extending in the radial direction is formed on the surface of the recess between the end of the large diameter portion 21b in the axial direction and the inner wall 12a of the molded motor housing 12. Further, a slight gap is formed in the bearing plate 13 between the inner diameter of the bearing hole 13a, the outer periphery of the small diameter portion 21a, and the small diameter portion 21a and the end portion in the axial direction where the bearing hole 13a of the bearing plate 13 is formed. Has been. The shaft 21 is pivotally supported by the bearing portions 13 b and 12 b by the bearing plate 13 and the motor housing 12.

  The motor housing 12 and the bearing plate 13 are kept sealed at the joint surface via an O-ring 25, and the pump housing 11 and the bearing plate 13 are kept sealed with an annular plate interposed therebetween. The housing 11, the bearing plate 13, and the motor housing 12 are fixed at several locations by fastening members 19 such as bolts.

  The bearing plate 13 has an inlet port 31a (opening) at a position for guiding a part of the high pressure fluid to the inner diameter side in the second fluid chamber 15b where the fluid pressure becomes high in the fluid chamber 15 of the pump housing 11. Is formed. Further, in the bearing plate 13, a flow path (first flow path) 31 communicating from the introduction port 31 a to the bearing portion 13 b and the bearing hole 13 a for bearing the shaft 21 from the second fluid chamber 15 b is provided on the shaft 21. It is formed in an oblique direction toward the small diameter portion 21a. In this case, the flow path 31 is formed so as to avoid a portion where the O-ring 25 for sealing the motor housing 12 and the bearing plate 13 is provided. The flow path 31 is formed in the bearing plate 13 with a hole obliquely toward the shaft 21 or after the hole is formed in the axial direction (plate thickness direction) of the bearing plate 13 from the position of the introduction port 31a. The hole is formed in an oblique direction from a step portion on the motor side (the end portion on the pump side of the motor housing 12) which is the opposite side. The flow path 31 guides fluid to the inlet 31a and the bearing portion 13b, lubricates and / or cools the bearing portion 13b, and uses a part of the fluid from the inlet 31a to make the bearing hole 13a and the small diameter portion. A fluid is supplied to the outer periphery of the shaft 21 from the bearing hole 13a through a gap formed between the outer periphery of the magnet 22 and the inner wall 12a. A part of the fluid having a high pressure is supplied to the bearing portion 12b.

  A channel 31a that communicates with the introduction port 31a and is formed in an oblique direction is closed at the end by the inner diameter end of the motor housing 12 provided with a stator. The fluid that has hit the end of the closed channel is blocked from flowing in the oblique channel, so that the fluid changes direction and flows into the gap between the bearing hole 13a and the small-diameter portion 21a. Supplied and guided to the axial end of the shaft 21 of the bearing portion 12b. In this case, if foreign matter is mixed in the fluid supplied to the shaft 21, rotation of the shaft 21 causes a malfunction, so that a filter for preventing foreign matter from entering the flow path 31 at the inlet 31 a. 38 is provided.

  Next, the operation of the pump device 10 will be described.

  When the coil 23 is energized by a controller (not shown) that drives the pump device 10, the pump device 10 starts driving. When the coil 23 is energized, excitation to the magnet 22 attached to the large-diameter portion 21b of the shaft 21 is switched. As a result, the shaft 21 to which the magnet 22 is fixed is pivoted to the bearing portions 13b and 12b. If it rotates integrally in the state supported, the impeller 16 attached to the shaft 21 will rotate. As the impeller 16 rotates, fluid is sucked from the suction port 11a of the pump housing 11, and the sucked fluid enters the first fluid chamber 15a. The fluid sucked into the first fluid chamber 15a is pumped to the second fluid chamber 15b provided on the outer diameter side of the first fluid chamber 15a by the rotation of the impeller 16, and then the pump housing 11 It is discharged from the discharge port 15c formed on the second fluid chamber 15b side to the outside of the pump device 10 (for example, an engine in a vehicle). The pump function of the pump device 10 is achieved by this series of fluid flows.

  In this embodiment, in such an operation process, a part of the fluid in the second fluid chamber 15b pumped from the first fluid chamber 15a by the rotation of the impeller 16 has a higher pressure than the suction port 11a. The fluid near the inlet 31a flows into the flow path 31 through the inlet 31a. The fluid guided to the flow path 31 is pumped by the rotation of the impeller 16, flows into the gap between the bearing hole 13a and the shaft 21, and is supplied to the bearing portion 13b. Here, the flow path 31 further extends via the inner diameter of the bearing hole 13a, but the end of the flow path 31 formed obliquely is blocked by the inner diameter end of the motor housing 12. It has become. Therefore, the fluid that has reached the gap between the bearing hole 13a and the shaft 21 flows along the axial direction of the shaft 21 to the gap between the magnet 22 and the inner wall 12a that molds the stator. In this case, the inner diameter of the bearing portion 13b is formed with a slit in the axial direction, and a plurality of slits 13s are provided in the radial direction at the end of the bearing hole 13a on the motor side. Thereby, the fluid which passes the flow path 31a flows without stagnation in the clearance gap between the outer periphery of the small diameter part 21a of the shaft 21, and the outer periphery of the magnet 22, and the inner wall 12a. Thereafter, the fluid flows along the outer periphery of the small diameter portion 21 c of the shaft 21 and is guided to the bearing portion 12 b of the shaft 21.

  Here, a passage (third passage) 21p is formed inside the shaft 21 so as to penetrate in the center in the axial direction and allow fluid to escape to the first fluid chamber 15a on the suction side. In this case, an escape hole 16b for allowing the fluid guided from the flow path 21p to escape to the first fluid chamber 15a is formed at the tip of the impeller 16 attached to the tip of the shaft 21. Accordingly, the fluid that has reached the bearing portion 12b of the shaft 21 passes through the flow path 21p formed in the shaft and the escape hole 16b of the impeller 16, and finally returns to the first fluid chamber 15a to return. ing.

  As described above, a series of processes in which a part of the fluid in the second fluid chamber 15b flows to the first fluid chamber 15a via the inlet 31a, the flow path 31, and the like have been described. When attention is paid to the pressure balance between the two fluid chambers 15b, the fluid in the first fluid chamber 15a is pumped to the second fluid chamber 15b by driving the impeller 16, so that when the pump is driven, The second fluid chamber 15b is in a higher pressure state than the first fluid chamber 15a. Therefore, the fluid is circulated without stagnation from the inlet 31a provided in the second fluid chamber 15b through the flow path 31 to the inside of the motor 20 and the first fluid chamber 15a.

  In such a configuration, the flow path 31 is formed in the bearing plate 13 in an oblique direction so as to avoid the O-ring 25, so that fluid is pumped to a necessary portion in the motor 20 for lubrication and / or cooling. The original function of the channel is not impaired. Furthermore, the filter 38 provided on the high-pressure side can reliably remove foreign matters contained in the fluid circulating inside, and can ensure higher lubricity, so that the reliability of the pump device 10 can be improved. Can be improved.

(Second Embodiment)
FIG. 2 shows a second embodiment. This second embodiment is basically the same as the first embodiment, and differs from the first embodiment in that the high pressure fluid is guided to the bearing portion of the shaft 21 and returned to the suction port side. The description of the same part is omitted, and the different part is described in detail.

  In the second embodiment, the flow path 31 is not formed in the bearing plate 13 but the flow path (second flow path) 33 is formed in the impeller 16.

  The impeller 16 is made of resin, and a metal bush 17 is inserted in the center, and is made by insert molding. The impeller 16 has a plurality of blades 16a and a base portion 16c that supports the blades 16a. A flow path 33 is formed in the base portion 16 c of the impeller 16 in the radial direction, and the flow path 33 passes through the bush 17. The flow path 33 is formed in the second fluid chamber 15b having a pressure higher than that of the discharge port 11a, and a filter 35 that prevents foreign matter from entering the flow path 33 is attached to the outer diameter thereof.

  On the other hand, since the shaft 21 is communicated with the flow path 33 formed in the impeller 16, a flow path (third flow path) 36 is formed in the radial direction, and the bearing portion 12 b is formed at the center of the shaft 16. A flow path (third flow path) 37 is formed in the axial direction from the end of the first end.

  With such a configuration, in the second embodiment shown in FIG. 2, a part of the fluid that has become high pressure due to the rotation of the impeller 16 is passed through the filter 35, thereby allowing foreign matter to enter the flow path 33 formed inside the impeller. After preventing the intrusion, the fluid is supplied from the center of the shaft 21 to the bearing portion 12b through the flow paths 33, 36, and 37, and then the fluid is supplied to the periphery of the shaft 21 and the inner wall 12a of the motor 20. By doing so, cooling and / or lubrication inside the motor including the shaft 21 is achieved. In this case, the fluid is supplied to the outer periphery of the shaft 21 or the inner wall 12a of the motor 20 and the bearing portions 12b and 13b using the gaps described in the first embodiment.

  With this configuration, cooling and / or circulation can be performed efficiently. In this case, since the filter 35 is provided at the fluid inlet, the foreign matter is collected by the filter 35. Since the filter 35 is provided on the outer diameter of the impeller 16, even if foreign matter exists on the outer diameter, the foreign matter is blown off to the outside of the impeller 16 by centrifugal force without adhering to the filter 35 due to the rotation of the impeller 16. No foreign matter is deposited on the surface of the filter 35. For this reason, the bearings 13 b and 12 b of the shaft 21 that rotates the impeller 16 can be protected by a simple configuration in which the filter 35 is provided at the inlet of the impeller 16.

  In the configuration shown in FIG. 2, when a fluid passes through the center of the shaft 21, if a metal shaft is used, the magnet 22 is fixed to the shaft 21, so that the magnet 22 passes through the filter by the magnetic force. The foreign matter having magnetism may be collected also by the magnetic force of the magnet. The shaft 21 is formed with a hole having a uniform diameter in the axial direction, but may be provided with a stop.

It is sectional drawing which shows the structure of the pump apparatus in 1st Embodiment of this invention. It is sectional drawing which shows the structure of the pump apparatus in 2nd Embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Pump apparatus 11 Pump housing 11a Suction port 12 Motor housing 12b, 13b Bearing part 13 Bearing plate 13a Bearing port 15 Fluid chamber 15a 1st fluid chamber 15b 2nd fluid chamber (high pressure part)
15c Discharge port 16 Impeller 16c Base 21 Shaft 23 Coil (stator)
24 core (stator)
31 channel (first channel)
31a Inlet 33, 35 Filter 36, 37 Flow path (third flow path)

Claims (5)

A pump housing in which a fluid chamber is formed, the fluid flowing through the fluid chamber is sucked from the suction port, and discharged from the discharge port;
A motor housing having a stator inside;
A shaft having one end protruding into the pump housing and an impeller attached thereto, and the other end pivotally supported in the motor housing;
A magnet attached to the shaft and disposed opposite to the stator;
In the pump apparatus provided with a bearing plate having a bearing portion disposed between the pump housing and the motor housing and rotatably supporting the shaft,
A first flow path for guiding fluid from the fluid chamber to the periphery of the shaft is formed inside the bearing plate, and the first flow path includes an opening facing the fluid chamber, and the opening, the bearing portion, A pump device characterized by communicating between the two. 2. The pump device according to claim 1, wherein the opening is formed in a high-pressure portion where a fluid pressure is high in the pump housing. The pump device according to claim 2, wherein the opening is provided with a filter. A pump housing in which a fluid chamber is formed, the fluid flowing through the fluid chamber is sucked from the suction port, and discharged from the discharge port;
A motor housing having a stator inside;
A shaft having one end protruding into the pump housing and an impeller attached thereto, and the other end pivotally supported in the motor housing;
In the pump device provided with the magnet attached to the shaft and arranged to face the stator,
The impeller is formed with a second flow path that guides the fluid to the inner diameter in the radial direction, and a third flow path that communicates with the second flow path and guides the fluid to the end of the shaft is formed in the shaft. The pump device is characterized in that a filter is provided at the inlet for introducing the fluid in the second flow path. The pump device according to claim 4, wherein the second flow path is formed in a base portion that supports a blade of the impeller.

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