JP5270513B2 - Electric water pump - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To remarkably increase magnetic efficiency in a motor part, to reduce processing cost, to reduce the number of parts, and to improve installation accuracy in respective parts. <P>SOLUTION: In a casing 1, an inner rotor 2, a waterproof housing 3 and a plurality of sintered cores 4 are provided. A plurality of opening parts 35 are formed on a circumferential surface of a cylindrical part 311 of the waterproof housing 3. A part of the sintered cores 4 is water-tightly constituted so as to project flush with an inner diameter surface of the waterproof housing 3 or by a proper quantity to its inner peripheral surface side from the opening part 35. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to an electric water pump that can remarkably increase the magnetic efficiency of a motor portion, has a low machining cost, has a small number of parts, and has a high accuracy in assembling each part.

In recent years, expectations and demands for low fuel consumption vehicles are increasing from an environmental point of view. Various means have been developed and implemented in order to achieve low fuel consumption, but the development and implementation of electrification of each component mounted on the vehicle is proceeding at a rapid pace with the hybridization of the vehicle.
Among motorized parts, the electric water pump is not only for cooling the engine, but also for optimizing the temperature of various parts in the vehicle (increasing and lowering the water temperature to achieve the optimum temperature). It is an indispensable part.

  As a method for increasing the magnetic efficiency of the motor portion of the electric water pump, it has been studied for some time to shorten the distance between the sintered core and the inner magnet. As a method for that purpose, Patent Document 1 below is a document using a sintered core (stator) as a part of a waterproof partition. In Patent Document 1, the distance between the stator and the rotor is shortened by using the stator as a part of the waterproof partition.

Patent No. 4087177

  The patent document 1 has the following problems. That is, in order to prevent water leakage, the flatness of the end surface of the core part 20 must be improved. If the flatness is poor, water leaks even if a sealing material is applied to the contact surface between the core portion 20 and the flange portion 24 and the contact surface between the core portion 20 and the bottom portion 22. In order to improve the flatness of the end face of the core part 20, the processing cost of the core part 20 increases. Moreover, since the core part 20 is assembled | attached to the flange part 24 and the bottom part 22 is assembled | attached to the core part 20, there were many faults, such as many parts count and assembly.

  Further, in Patent Document 1, since the core portion 20 is assembled to the flange portion 24 and the bottom portion 22 is assembled to the core portion 20, the support shaft 30 attached to the bottom portion 22 is attached with a slight inclination due to accumulation of assembly errors. End up. That is, the concentricity of the pump part 14 to which the support shaft 30 is attached and the bottom part 22 is deteriorated by assembling many parts in combination. Along with this, the impeller 32 is also slightly inclined and rotated, so that the pump performance is deteriorated. In addition, since the impeller rotates slightly tilted, there is a disadvantage that the bearing disposed on the inner periphery of the impeller 32 is unevenly worn and the bearing life is shortened.

  Therefore, the problem (technical problem or purpose) to be solved by the present invention can significantly increase the magnetic efficiency of the motor part, the processing cost is low, the number of parts is small, and the assembly accuracy of each part It is to realize a sintered core waterproof structure of an electric water pump that is remarkably superior.

  Accordingly, as a result of intensive researches to solve the above-mentioned problems, the inventor has the invention of claim 1 comprising an inner rotor, a waterproof housing and a plurality of sintered cores in a casing, and the cylinder of the waterproof housing. A plurality of openings are formed on the circumferential surface of the shaped portion, and a watertight structure is formed so that a part of the sintered core protrudes from the opening to the same or the inner peripheral surface side of the waterproof housing. The above-described problem is solved by using an electric water pump characterized by the above.

  The electric water pump according to claim 2, wherein the opening of the waterproof housing and a part of the sintered core are sealed with an annular rubber elastic material in claim 1. As a result, the above-described problems have been solved. According to a third aspect of the present invention, in the first or second aspect, the sintered core is set in the opening from the outside of the waterproof housing, and the outer periphery of the plurality of sintered cores is fixedly installed by the casing. By solving the above-described problem, the above-described problem is solved.

  According to a fourth aspect of the present invention, in the third aspect of the present invention, the opening is formed with a substantially opening on the inner peripheral side of the waterproof housing, and a storage groove on the outer side for receiving the rubber elastic material. An inner peripheral surface of the end portion is formed at the inner end of the tooth portion, and a rear outer peripheral portion is formed in the rear portion thereof so that the rubber elastic material can be contained therein. The above-mentioned problem is solved by providing an electric water pump characterized in that the electric water pump is in contact with the outer peripheral side of the waterproof housing.

  According to a fifth aspect of the present invention, in the first or second aspect, the sintered core is set in the opening from the inner peripheral side of the waterproof housing, and the outer end surface of the sintered core is fixed with a screw or the like at the back yoke. The above-described problems are solved by using an electric water pump characterized by being formed. According to a sixth aspect of the present invention, in the fifth aspect of the present invention, the opening has a substantial opening on the outer peripheral side of the waterproof housing, and a storage groove into which the rubber elastic material is placed on the inner side. A flange portion is formed at the inner end of the T-shaped portion of the core, and the rubber elastic material is formed on the outer peripheral side of the flange portion, and the peripheral surface of the flange portion is held while holding the rubber elastic material. The electric water pump, which is in contact with the inner surface of the thin plate portion of the waterproof housing, solves the above problems.

  In the invention of claim 1, in particular, since the waterproof housing wall is not present between the inner rotor and the sintered core, the distance between the inner rotor and the sintered core can be shortened. And there is the biggest advantage that can be raised. This point will be described in detail. In this type of electric water pump, the waterproof housing is an essential configuration as a waterproof partition, and the sintered core is also an essential configuration for rotating the inner magnet. While providing a waterproof housing and waterproof sealing, a part of the sintered core is used as a part of the waterproof partition, so that there is no waterproof housing wall between the inner rotor and the sintered core. Since the distance between the sintered cores can be shortened, there is an advantage that the magnetic efficiency can be improved. That is, only the circulating water is provided between the inner rotor and the sintered core, and the magnetic force from the sintered core can be transmitted to the inner rotor with almost no decrease, so that the magnetic efficiency can be improved. Furthermore, the waterproof housing to which the shaft is attached is a single member, and therefore the accuracy of assembly of the shaft is high, so that the concentricity can be increased. Therefore, noise is low, bearing life is long, and pump performance can be improved.

    In the invention of claim 2, since the seal structure is water-tight with the annular rubber elastic material, the water-tightness can be secured easily and reliably, and the same effect as in claim 1 can be obtained. In the invention of claim 3, by setting the sintered core from the outer peripheral side of the waterproof housing, assembly errors at the time of assembly do not accumulate, so the sintered core does not have so high processing accuracy. High assembly accuracy can be obtained. In the invention of claim 4, since the sintered core is inserted into the opening of the waterproof housing constituted by one member, and the specific part of the sintered core is brought into contact with the opening of the waterproof housing, the teeth portion It is possible to accurately determine the position of the inner peripheral surface, and to exhibit desired characteristics.

  In particular, if the annular rubber elastic material (O-ring or the like) is pre-baked on the sintered core, the assembly time can be shortened. Moreover, since the said cyclic | annular rubber elastic material does not fall at the time of an assembly | attachment, an operator's burden can be eased. Furthermore, if the insulator is integrally formed on the sintered core in advance, the assembly time can be shortened. In this way, the annular rubber elastic material and the insulator are attached to the sintered core before assembly. The number of parts handled by the person can be reduced.

  In the invention of claim 5, even when the sintered core is set from the inner peripheral side of the waterproof housing, high assembly accuracy can be obtained, and most of the sintered core penetrates the waterproof housing. As a result, the sintered core can hardly be detached from the waterproof housing after insertion, thereby making it easy to attach the back yoke. In the invention of claim 6, since the flange portion at the inner end of the T-shaped portion of the sintered core is difficult to be detached from the waterproof housing, the back yoke is an attaching operation after the sintered core is inserted into the waterproof housing. There is an advantage that the fixing work process of the sintered core can be easily performed with screws or the like from the outer peripheral side of the steel.

(A) is sectional drawing of 1st Embodiment of this invention, (B) is the principal part expanded sectional view of (A), (C) is the (a) part enlarged view of (B). (A) is the state figure made into the partial cross section just before attachment of 1st Embodiment of this invention, (B) is the state figure in the middle of attachment, (C) is the state figure which completed attachment. FIG. 2 is a cross-sectional view taken along line Y1-Y1 in FIG. (A) is sectional drawing of the waterproof housing and rubber elastic material of 1st Embodiment of this invention, (B) is Y2-Y2 arrow sectional drawing of (A), (C) is the perspective view which partially cut off the waterproof housing. FIG. 4D is a perspective view of the sintered core. (A) is sectional drawing of 2nd Embodiment of this invention, (B) is the principal part expanded sectional view of (A), (C) is the (a) part enlarged view of (B). (A) is sectional drawing which isolate | separated members in 2nd Embodiment of this invention, (B) and (C) are the state figures in the middle of attachment of 2nd Embodiment of this invention. FIG. 6 is a cross-sectional view taken along arrow Y3-Y3 in FIG. It is the perspective view which isolate | separated the member of the sintered core of 2nd Embodiment of this invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. The main elements of the present invention include a casing 1 serving as a motor case, an inner rotor 2, a waterproof housing 3 serving as a partition, a sintered core 4 serving as a stator core, an annular rubber elastic material 5, and the like. It consists of and. In particular, there are a plurality of embodiments of the sintered core 4. First, in 1st Embodiment, it is the type attached from the outer peripheral side of the said waterproof housing 3. FIG. The second embodiment is a type that is attached from the inner peripheral side of the waterproof housing 3.

  As shown in FIG. 1A, the casing 1 includes a motor chamber side casing 11 and a pump chamber side casing 12, and the motor chamber side casing 11 is formed in a substantially cylindrical chamber. . One end side in the axial direction of the motor chamber side casing 11 is divided from the pump chamber side casing 12 and is configured to be watertightly coupled with a sealant. The motor chamber side casing 11 and the pump chamber side casing 12 are continuous portions where no partition wall or the like is present. Here, the axial direction of the casing 1 indicates the same direction as the axial direction of the shaft 7 that supports the inner rotor 2 described later.

  The large opening 13 (downward in FIG. 1A) of the casing 1 has the above-described shaft 7, inner rotor 2, waterproof housing 3, sintered core 4, annular rubber elastic material such as O-ring 5, circuit board 6. In order to assemble etc. in the casing 1, the opening serves as an inlet for inserting and disposing the above-mentioned constituent members in the casing 1. As shown in FIG. 1A, the pump chamber casing 12 is formed with a suction port 12a and a discharge port 12b, and a shaft fixing portion 14 is formed. That is, with the inner rotor 2, the waterproof housing 3, the sintered core 4, and the like mounted in predetermined positions in the casing 1, the impeller 21 is mainly present, and the space in which the fluid moves is the pump chamber side casing 12. The air gap in which the rotor magnet 22 and the sintered core 4 are present is the motor chamber casing 11.

  As shown in FIGS. 1A and 3, the inner rotor 2 includes an impeller 21 and a rotor magnet 22, and the inner rotor 2 is rotatably attached to the shaft 7. There are cases where the impeller 21 and the rotor magnet 22 are integrally molded and cases where they are formed as separate members. The rotor magnet 22 is a plastic magnet, which is a mixture of fine magnet powder and a binding resin, and may be formed integrally with the impeller 21.

  The rotor magnet 22 has a cylindrical shape, and each of them is made of a plastic magnet or an embedded magnet and is formed as an integral unit. First, for example, in the case of a 6-pole type, the rotor magnet 22 is configured as a permanent magnet so that the circumference is divided into 6 equal parts at intervals of 60 degrees and alternated with S poles, N poles,.

  The waterproof housing 3 is made of synthetic resin as a material, and serves as a partition wall between the pump chamber and the sintered core chamber. The waterproof housing 3 is composed of a cup-shaped part 31, a bowl-shaped part 32, and a circumferential outer edge 33, as shown in FIGS. 4 (A), (B) and (C). The cup-shaped portion 3 1 includes a cylindrical portion 311 and a bottom portion 312, and a shaft fixing portion 34 is formed on the bottom portion 312. The shaft fixing portion 34 serves to support the shaft 7 together with the shaft fixing portion 14 of the casing 1. The bowl-shaped portion 32 is formed in a substantially disc shape so as to protrude in the diametrical direction from the periphery of the cup-shaped portion 31 on the opening 31a side, and the outermost circumferential side is lowered with a step. The circumferential outer edge 33 has an annular shape with a groove 332 for receiving the O-ring 331.

  The cylindrical portion 311 of the cup-shaped portion 3 1 of the waterproof housing 3 is provided with the same number of openings 35 as the sintered core 4. The shape of the opening 35 is slightly larger than the inner peripheral surface 41a of the tooth portion 41 so that the inner peripheral surface 41a of the tooth portion 41 can be inserted, and the teeth portion needs to be sealed by the annular rubber elastic material 5. The size of the inner peripheral surface 41a is not too large. As shown in FIG. 3, the size of the opening on the “outer peripheral side” of the waterproof housing is larger, and the size of the opening on the “inner peripheral side” of the waterproof housing is smaller. This is for arranging an O-ring.

  The specific shape of the opening 35 is the same square as the end inner peripheral surface 41 a of the tooth portion 41. Assuming that the thickness L0 of the cross section of the opening 35 (see FIG. 2C and FIG. 4A) is the substantial opening having a relatively thin thickness La on the inner peripheral side of the cylindrical portion 311. A portion 35a is formed, and on the outer peripheral side, a storage groove portion 35b is formed with a predetermined depth Lb as a space in which the annular rubber elastic material 5 can be stored. The thickness La + the depth Lb = L0 (cross-sectional thickness of the opening 35), and the thickness Ls = L0 or Ls≈L0 of the end inner peripheral surface 41a of the tooth portion 41 is configured.

  Further, the vertical height Ha of the rear side outer peripheral portion 41b of the tooth portion 41 is formed to be larger than both inner surface heights Hb of the storage groove portion 35b in the vertical direction. That is, the outer peripheral portion 41b on the rear side of the teeth portion 41 and the peripheral wall of the storage groove portion 35b of the annular rubber elastic material 5 (the outer wall surface of the cylindrical portion 311 in the vicinity of the opening portion 35 of the waterproof housing 3) are in contact with each other. 4, the size of the outer peripheral side of the opening 35 of the waterproof housing, that is, the peripheral wall of the storage groove 35 b is the outer periphery of the rear position after the annular rubber elastic material 5 (such as an O-ring) provided on the teeth 41 is attached. It is smaller than the surface.

  The depth Lb of the storage groove portion 35b of the annular rubber elastic material 5 in the opening 35 needs to crush the annular rubber elastic material 5 and seal the cooling water. It is configured to be shallower than the diameter (horizontal direction in FIG. 1C). With such a configuration, as shown in FIGS. 1B and 1C, even if pressure is applied from the “outer peripheral side” of the waterproof housing, the end inner peripheral surface 41 a of the tooth portion 41 is cylindrical. Without protruding from the opening 35 of the part 311, it can be in a flush state or in a state protruding by a slight distance. The distance between the rotor magnet 22 and the rotor magnet 22 can be reduced to a small distance ΔL (about 1 mm).

  The sintered core 4 will be described in detail. The material is a sintered body. If it says in detail, it will be good if it is a sintered compact by magnetic powder (what is called iron powder), but if it is a magnetic stainless steel powder as mentioned later, it has a rust prevention effect and is still more suitable. The overall shape of the sintered core 4 is “H”. A tooth-shaped portion on the inner peripheral side of the sintered core 4 is referred to as a tooth portion 41. A portion whose outer shape is reduced on the innermost peripheral surface side of the tooth portion 41 in a state where the annular rubber elastic member 5 is wound around is referred to as an end inner peripheral surface 41a. The teeth portion 41 having a larger diameter on the rear side is referred to as a rear side outer peripheral portion 41b.

  Specifically, an insulator 43, which is a thin synthetic resin having a function as an insulation, is disposed so as to cover the entire sintered core 4 (see FIG. 1). Since the end inner peripheral surface 41a of the tooth portion 41 needs to be brought close to the rotor magnet 22, the insulator 43 does not exist. In addition, there are two embodiments of means for assembling the insulator 43 to the sintered core 4. First, the sintered core 4 is assembled by combining the insulators 43 in the shape of upper and lower halves of the sintered core 4 from above and below. It is a technique to cover. The second is a method in which a thin synthetic resin is molded and covered around the sintered core 4 and integrally molded with the sintered core 4.

  If an insulator 43 made of synthetic resin is integrally formed on the outer surface of the sintered core 4 (excluding the end inner peripheral surface 41a) before assembling, time for assembling the insulator 43 at the time of assembling becomes unnecessary. Therefore, assembly time can be reduced. In addition, the number of parts handled by the worker is reduced, leading to a reduction in labor. Further, a coil M by winding is wound around an intermediate portion of “H” which is a constricted portion of the insulator 43 covering the sintered core 4, and this is also wound before assembling. Further, if the annular rubber elastic material 5 is baked and fixed on the rear side outer peripheral portion 41b of the tooth portion 41, the operation for attaching the annular rubber elastic material 5 at the time of actual assembly becomes unnecessary, so that the assembly time is reduced. it can. In addition, the number of parts handled by the operator is reduced, leading to a reduction in labor.

  The assembly work will be described. As shown in FIG. 3, the end inner peripheral surface 41 a of the tooth part 41 is inserted into the opening 35 from the outer peripheral side of the waterproof housing 3, and the annular rubber elastic material 5 is attached to the rear side outer peripheral part 41 b of the tooth part 41. While being crushed, the rear outer peripheral portion 41b is brought into contact with the peripheral wall of the storage groove 35b (the outer wall surface of the cylindrical portion 311 in the vicinity of the opening 35 of the waterproof hooding 3), and the end inner peripheral surface 41a of the sintered core 4 To accurately position. Specifically, it protrudes inward from the inner peripheral surface of the waterproof housing 3 by the same surface as the inner peripheral surface of the opening 35 of the waterproof housing 3 or by a very small distance ΔS [FIG. )reference〕. This is to securely hold the annular rubber elastic material 5. In this state, the process goes to a step of fixing the plurality of sintered cores 4 as the sintered cores by attaching them in the casing 1.

  In a state before being mounted in the casing 1, the sintered core is detached due to the elastic repulsive force of the rubber of the annular rubber elastic member 5 and cannot be fixed. For this reason, in order to fix the position of the sintered core 4, the sintered core 4 is inserted into the casing 1 and fixed in a state where the sintered core 4 is temporarily fixed. That is, the plurality of circular sintered cores 4, 4,... Are fixed as if the casing 1 was fitted with a tag (see FIG. 1 (A) and FIG. 3). Thereby, the sintered core 4 is fixed without coming off. The casing 1 is made of cast aluminum alloy or resin.

  According to the configuration as described above, the waterproof partition is constituted by a single part, which is mostly the waterproof housing 3. Only the opening 35 of the waterproof housing 3 is configured as a sealed partition wall by the end inner peripheral surface 41 a of the tooth portion 41. For this reason, in this invention, a waterproof partition is comprised by the waterproof housing 3 and the edge part internal peripheral surface 41a of the teeth part 41. FIG. Among the sintered cores 4, only the end inner peripheral surface 41 a of the tooth portion 41 is always in contact with the cooling water, and therefore needs to have a rust prevention function. Therefore, it is preferable that the end inner peripheral surface 41a of the tooth portion 41 is painted or plated, or a sintered body made of stainless powder that is not easily rusted.

  The second embodiment of the sintered core 4 is an assembly method in which substantially the entire sintered core 4 is inserted into the opening 35 of the waterproof housing 3 from the inner peripheral side of the waterproof housing 3. As described above, since the sintered core 4 is inserted from the “inner peripheral side” of the waterproof housing 3, the sintered core 4 in this case has a T-shape. In the H shape, the outer peripheral side piece portion 42 of the sintered core 4 is formed to be larger than the opening portion 35 and cannot be inserted. In order to avoid this, the shape is T-shaped, and the sintered core 4 has two members. It consists of a T-shaped part 4A and a separate back yoke (sintered yoke) 4B. A bobbin 4C is also provided. The bobbin 4C is a synthetic resin and has an insulating function between the sintered core 4 and the coil M.

  Since the opening 35 in this case is inserted from the “inner peripheral side” of the waterproof housing 3 in the direction opposite to that of the first embodiment, the sintered core 4 is inserted in the “inner side of the waterproof housing 3 in the opening 35 of the waterproof housing 3. The size of the “peripheral side” is larger than the size of the “outer peripheral side” of the waterproof housing 3 (see FIG. 5). When the opening 35 of the waterproof housing 3 is different in size from the “inner peripheral side” and the “outer peripheral side”, a step is formed when the opening 35 of the waterproof housing 3 is viewed in cross section. The shaped part 4a can contact there.

  The difference in size between the “inner circumferential side” and “outer circumferential side” of the opening 35 of the waterproof housing 3 may be such that the teeth of the sintered core can be positioned without rattling. Even with MAX, about 1 mm is sufficient. The annular rubber elastic material 5 is inserted to the base of the flange 45 of the T-shaped part 4A of the sintered core 4 and is disposed at the root of the flange 45. An outer frame shape of the annular rubber elastic material 5 is formed to be slightly smaller than a substantial opening 35 a of the opening 35 of the waterproof housing 3, and the annular rubber elastic material 5 is a T-shaped portion of the sintered core 4. It is sandwiched between the flange 45 of 4A and the flange 46 of the bobbin 4C.

  In this way, the annular rubber elastic material 5 includes the opening 35 of the waterproof housing, the flange 45 of the T-shaped portion 4A of the sintered core 4, and the rectangular section of the T-shaped portion 4A of the sintered core 4. The bobbin 4C is disposed in a mounting space such as an O-ring formed by the four surfaces of the flange 46. As for the shape of the bobbin 4C, a collar portion is formed at one end, and further, a planar crescent-shaped portion (see a chain line in FIG. 8) of the back yoke 4B is provided, and a cylindrical portion having a rectangular cross section is provided in the middle. . In addition, a flange-like portion 46 having a circular arc shape is provided at the other end so as to be adjacent to the waterproof housing 3. As a result, the cross section has a shape in which the gates are arranged vertically symmetrically. Further, the shape of the sintered core 4 and the bobbin 4C in the second embodiment is similar to the shape of the sintered core 4 in the first embodiment. A coil M is wound on the outside of a cylindrical portion having a square cross section in the middle of the bobbin 4C.

  By the way, the flange portion 45 of the T-shaped portion 4A of the sintered core 4 and the flange portion 46 of the bobbin 4C come into contact with the opening 35 of the waterproof housing 3 from the “inner peripheral side” and “outer peripheral side”, respectively. The distance between the flange 45 of the binding core 4 and the flange 46 of the bobbin 4C is equal to the thickness La of the substantial opening 35a at the “outer peripheral side” of the opening 35 of the waterproof housing 3 [ See FIG. 5C]. In addition, the annular rubber elastic material 5 is crushed by the proximity of the flange 45 of the sintered core 4 and the flange 46 of the bobbin 4C, so that the annular rubber elastic material 5 has a sealing property against cooling water. The distance between the flange portion 45 of the T-shaped portion 4A of the sintered core 4 and the flange portion 46 of the bobbin 4C (= the thickness of the substantial opening portion 35a of the waterproof housing 3) is the annular rubber elastic material 5 It is formed smaller than the diameter.

  Further, as shown in FIG. 5C, the protrusion amount of the flange portion 45 of the T-shaped portion 4A is slightly spaced ΔS or flush, and the distance ΔL with the rotor magnet 22 is small. This can be performed in the same manner as the embodiment [see FIG. The back yoke 4B is configured to be freely attachable to the rear side (outer peripheral side) of the T-shaped portion 4A with a fastener 4D such as a screw in order to fix the sintered core 4 and the bobbin 4C. When the back yokes 4B, 4B,... Of the sintered core 4 are continuous in a plan view, a cylindrical shape is obtained. That is, the bobbin 4C, the annular rubber elastic material 5, and the waterproof housing 3 are sandwiched between the flange portion 45 of the sintered core 4 and the back yoke 4B. The casing 1 is arranged on the outer peripheral side of the back yoke 4B in the same manner as in the first embodiment.

  The assembling work of the second embodiment of the present invention will be described. A coil M is wound around the bobbin 4C in advance. In addition, the annular rubber elastic material 5 is inserted in advance into the flange portion of the T-shaped portion 4A. At the time of actual assembly, the T-shaped portion 4A is inserted from the “inner peripheral side” of the waterproof housing 3 in the opening 35 of the waterproof housing 3, and the sintered core is inserted into the step formed in the opening 35 of the waterproof housing 3. The collar portion 45 of the T-shaped portion 4A is brought into contact. Then, a bobbin 4C in which a coil M is wound around the four corners of the T-shaped portion 4A of the sintered core 4 protruding from the waterproof housing 3 is inserted, and the bobbin 4C is brought into contact with the waterproof housing 3 Let Next, in this state, the back yoke 4B is brought into contact with the front end of the four corners of the T-shaped portion 4A of the sintered core 4, and the sintered core is fixed from the outer peripheral surface of the back yoke 4B with a fixing tool 4D such as a screw. 4 Fix as a whole. Thereby, the bobbin 4C, the annular rubber elastic member 5, and the waterproof housing 3 are fixed in a sandwich shape by the combined sintered core 4.

DESCRIPTION OF SYMBOLS 1 ... Casing, 2 ... Inner rotor, 3 ... Waterproof housing, 4 ... Sintered core,
5 ... cyclic rubber elastic material, 31 ... cup-shaped part, 32 ... bowl-shaped part, 311 ... cylindrical part,
35 ... Opening part, 35a ... Substantial opening part, 35b ... Storage groove part, 41 ... Teeth part,
41a ... end inner peripheral surface, 41b ... rear side outer peripheral part, 42 ... outer peripheral side piece part,
4A ... T-shaped part, 4B ... back yoke, 4C ... bobbin.

Claims (6)

  An inner rotor, a waterproof housing and a plurality of sintered cores are provided in the casing, and a plurality of openings are formed on the circumferential surface of the cylindrical portion of the waterproof housing, and a part of the sintered core is formed from the openings. An electric water pump comprising a watertight structure so as to protrude from the inner surface of the waterproof housing by an appropriate amount.   2. The electric water pump according to claim 1, wherein a gap between the opening of the waterproof housing and a part of the sintered core is sealed with an annular rubber elastic material.   3. The electric water pump according to claim 1, wherein the sintered core is set in the opening from the outside of the waterproof housing, and the outer periphery of the plurality of sintered cores is fixedly installed by the casing. .   4. The opening according to claim 3, wherein the opening is formed with a substantially opening on the inner peripheral side of the waterproof housing, and a storage groove portion into which the rubber elastic material is inserted on the outer side. An inner peripheral surface of the end portion is formed with an outer peripheral portion on the rear side in which the rubber elastic material is inserted in the rear portion thereof, and the outer peripheral surface of the rear side is held on the outer peripheral side of the waterproof housing while holding the rubber elastic material. An electric water pump characterized by being in contact with   3. The sintered core according to claim 1, wherein the sintered core is set in the opening from an inner peripheral side of the waterproof housing, and an outer end surface of the sintered core is fixed by a screw or the like at a back yoke. Electric water pump.   6. The opening according to claim 5, wherein the opening is formed with a substantially opening on the outer peripheral side of the waterproof housing, and on the inside with a storage groove into which the rubber elastic material is inserted, and an inner end of the T-shaped portion of the sintered core. Are formed so that the rubber elastic material can be inserted into the outer peripheral side of the flange portion, and the peripheral surface of the flange portion contacts the inner surface of the thin plate portion of the waterproof housing while holding the rubber elastic material. An electric water pump characterized by being in contact with each other.

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