JP2018150841A - Fuel pump - Google Patents

Abstract

Provided is a fuel pump that can be configured while omitting a portion covering the outer periphery of a stator core of a metal housing. A fuel pump includes a stator core, a rotor rotating by a rotating magnetic field formed on an inner peripheral side of the stator core, and an impeller rotating integrally with the rotor to suck the fuel. The pump parts 5 and 54 to be discharged to the side, the resin housings 6 and 41 integrally formed with the stator core 2 by insert molding, and the outer periphery of the pump parts 5 and 54 are covered, and the pump parts 5 and 54 side from the stator core 2 And metal housings 7 and 42 coupled to the outer peripheries of the resin housings 6 and 41. [Selection] Figure 1

Description

  The present invention relates to a fuel pump that is driven by rotation of a rotor arranged on the inner peripheral side of a stator core.

  2. Description of the Related Art Conventionally, there has been known a fuel pump configured to suck fuel by a rotating member that rotates integrally with a rotor disposed on the inner peripheral side of a stator core and discharge the fuel to the rotor side (see, for example, Patent Document 1). The fuel pump of Patent Document 1 includes a cylindrical metal housing. The metal housing has a convex portion with a smaller inner diameter on the inner peripheral side, and has a concave portion with an inner diameter larger than the convex portion on both sides in the axial direction.

  The stator core and the resin end cover are accommodated in one recess of the metal housing, and the pump case is accommodated in the other recess. The pump case and the impeller as a rotating member housed in the pump case constitute a pump unit that sucks fuel and discharges it to the rotor side. Thus, the fuel pump of patent document 1 is comprised by accommodating each component in a metal housing and couple | bonding each component.

Japanese Patent No. 4899991

  However, in the fuel pump of Patent Document 1, each component is housed in a metal housing and each component is coupled, so the outer periphery of the stator core is covered with the metal housing. For this reason, the metal housing increases the weight, diameter, and cost of the fuel pump.

  An object of the present invention is to provide a fuel pump that can be configured while omitting a portion covering the outer periphery of a stator core of a metal housing in view of the problems of the prior art.

The fuel pump according to the first invention is
A stator core;
A stator coil provided in the stator core for forming a rotating magnetic field on the inner peripheral side of the stator core;
A rotor disposed on the inner peripheral side of the stator core and rotated by the rotating magnetic field;
A pump unit that rotates integrally with the rotor, sucks fuel by rotation of the rotating member, and discharges the fuel to the rotor;
A resin housing formed integrally with the stator core by insert molding;
A metal housing that covers the outer periphery of the pump portion and is coupled to the outer periphery of the resin housing on the pump portion side of the stator core.

  According to the first aspect of the invention, the metal housing covers the outer periphery of the pump portion and is coupled to the resin housing integral with the stator core on the pump portion side with respect to the stator core. For this reason, the part which covered the outer periphery of the stator core in the conventional metal housing is omissible. Thereby, the weight reduction, diameter reduction, and cost saving of a fuel pump can be achieved.

  In the fuel pump according to a second aspect of the present invention, in the first aspect, the resin housing covers an outer periphery of the stator core.

  According to the second invention, since the outer periphery of the stator core is covered with the resin housing, it is possible to prevent the fuel from leaking from the inside of the stator core to the outside through the gap of the stator core.

A fuel pump according to a third aspect of the present invention is the first or second aspect of the invention,
The resin housing has a step portion having a drop on the stator core side on the outer periphery on the pump portion side than the stator core,
The metal housing has a caulking portion joined to the step portion at an end portion on the stator core side,
The metal housing is coupled to the outer periphery of the resin housing by the caulking portion.

  According to the third invention, since the metal housing and the resin housing are coupled by the caulking portion of the metal housing, it is possible to firmly couple the metal housing and the resin housing without using a member other than the metal housing and the resin housing. it can.

A fuel pump according to a fourth invention is the first or second invention,
The metal housing includes a plurality of projecting pieces extending to the outer periphery of the resin housing and having convex portions or concave portions,
On the outer periphery of the resin housing, a concave portion or a convex portion that engages with a convex portion or a concave portion of each protruding piece is provided,
The plurality of projecting pieces and the recesses or projections of the resin housing constitute a snap fit mechanism that joins the metal housing to the outer periphery of the resin housing.

  According to the fourth aspect of the invention, the metal housing and the resin housing are coupled by the snap fit mechanism configured by the plurality of projecting pieces of the metal housing and the concave or convex portion of the resin housing. The metal housing and the resin housing can be easily combined without the need to use the.

A fuel pump according to a fifth aspect of the invention is any one of the first to fourth aspects of the invention,
The pump section includes a pump case on the suction side and a pump case on the discharge side,
The suction-side and discharge-side pump cases have end surfaces of these outer edge portions in axial contact with each other to form a pump chamber inside,
The pump case on the discharge side is provided with an engagement surface facing the stator core side,
The metal housing is
A protrusion that protrudes inward from the inner peripheral surface of the metal housing and contacts the engagement surface;
A caulking portion that is provided at an end of the metal housing opposite to the stator core and is joined to the pump case on the suction side by caulking;
The suction-side and discharge-side pump cases are sandwiched between the projecting portion and the caulking portion so as to seal between the end surfaces.

  According to the fifth aspect of the invention, the suction side and the discharge side pump cases are sandwiched between the protruding portion and the caulking portion of the metal housing, so that a large axial compressive force can be applied between them. Therefore, the end surfaces of the pump case outer edge portions on the suction side and the discharge side can be tightly pressed and sealed to maintain the sealing performance against the fuel.

  According to a sixth aspect of the present invention, in the fuel pump according to any one of the first to fifth aspects, the resin housing forms a cover that covers an end portion of the stator core opposite to the pump portion.

  According to the sixth aspect of the invention, the resin housing forms a cover that also covers the end of the stator core on the side opposite to the pump portion, so there is no need to provide such a cover separately. For this reason, the number of parts constituting the fuel pump can be reduced.

It is sectional drawing which shows the structure of the fuel pump which concerns on one Embodiment of this invention. It is sectional drawing which shows the structure of the fuel pump which concerns on another embodiment of this invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following description, “suction side” means the lower side in FIG. 1, and “discharge side” means the upper side.

  As shown in FIG. 1, a fuel pump 1 according to an embodiment of the present invention includes a stator core 2, a stator coil 3 provided on the stator core 2, a rotor 4 disposed on the inner peripheral side of the stator core 2, a fuel The pump part 5 which inhales and discharges to the rotor 4 side, the resin housing 6 integrally formed with the stator core 2 by insert molding, and the metal housing 7 covering the outer periphery of the pump part 5 are provided.

  The fuel pump 1 can be used as an inline type disposed outside a fuel tank (not shown). The stator coil 3 is for forming a rotating magnetic field on the inner peripheral side of the stator core 2. By controlling energization to the stator coil 3, a rotating magnetic field is formed in which the magnetic field moves in the circumferential direction along the inner periphery of the stator core 2.

  The rotor 4 includes a rotating shaft 8 and a permanent magnet 9 fixed around the rotating shaft 8, and rotates by receiving a force in a rotating direction from a rotating magnetic field by the permanent magnet 9. That is, the stator core 2, the stator coil 3, and the rotor 4 constitute a brushless motor. An insulator 3a is provided between the stator coil 3 and the stator core 2 to electrically insulate them.

  The pump unit 5 includes a resin impeller 10 as a rotating member that rotates integrally with the rotor 4 in order to suck and discharge the fuel to the rotor 4 side, and a metal pump case 11 having a pump chamber. . The impeller 10 is fixed to the suction side end of the rotary shaft 8 and is accommodated in the pump chamber.

  That is, the pump unit 5 constitutes a cascade pump that rotates the disk-shaped impeller 10 at a high speed in the pump chamber, sucks fuel from the fuel inlet 12, boosts the pressure, and discharges the fuel to the rotor 4 side.

  The resin housing 6 covers the outer periphery of the stator core 2 and extends to the suction side from the stator core 2 through a groove provided on the inner peripheral surface of the stator core 2 so as to be integrated with the stator core 2.

  Further, the resin housing 6 forms a cover that covers an end portion of the stator core 2 opposite to the pump portion 5. That is, the resin housing 6 functions as an end cover that covers the discharge-side end face of the stator core 2, the portions of the stator coil 3 and the insulator 3 a that protrude further to the discharge side, and the discharge side of the rotor 4.

  The resin housing 6 has one end connected to the stator coil 3 and the other end extended to the outside of the resin housing 6, a radial bearing 14 that radially supports the discharge-side end of the rotary shaft 8, A fuel discharge port 15 is provided for supplying fuel discharged from the pump unit 5 to the engine side. A passage hole 16 through which fuel from the rotor 4 side toward the fuel discharge port 15 passes is provided in a portion on the discharge side of the rotary shaft 8 of the radial bearing 14.

  The portion of the resin housing 6 that extends from the suction side end surface of the stator core 2 to the suction side covers the portions of the stator coil 3 and the insulator 3a that protrude from the suction side end surface of the stator core 2 to the suction side, and is integrated therewith. Yes. An annular recess 17 is provided on the outer peripheral portion of the resin housing 6 on the pump portion 5 side than the stator core 2. The inner wall on the suction side of the annular recess 17 forms a step portion having a drop on the stator core side.

  The outer peripheral surface 18 on the suction side of the annular recess 17 of the resin housing 6 is press-fitted into the inner peripheral surface of the metal housing 7 on the discharge side. An end of the metal housing 7 on the stator core 2 side is a caulking portion 19 that is bent inward of the annular recess 17 and joined to a stepped portion formed by an inner wall of the annular recess 17 on the suction side. The resin housing 6 and the metal housing 7 are joined by the caulking portion 19.

  The pump case 11 has a discharge side case 20 and a suction side case 21, and end surfaces of these outer edge portions are in contact with each other in the axial direction to form a pump chamber inside. The discharge-side case 20 has a convex shape with a central portion protruding to the discharge side as seen in the cross section of FIG. 1, and has a small-diameter portion on the discharge side and a large-diameter portion 22 on the suction side having a larger outer diameter. It consists of.

  The small-diameter portion constitutes a protruding cylindrical portion 24 having a radial bearing 23 on the inner peripheral side. The radial bearing 23 supports the rotary shaft 8 in the radial direction on the discharge side from the impeller 10. A gap 25 is formed between the projecting cylindrical portion 24 and the portion of the resin housing 6 that extends from the stator core 2 to the suction side, through which fuel discharged from the pump portion 5 passes.

  The large-diameter portion 22 has an annular stepped portion 26 having a cross-sectional shape such that the protruding end portion of the outer peripheral portion is cut out in an L shape. The annular step portion 26 includes a small-diameter annular surface 27 having a slightly smaller diameter than the outer peripheral portion of the large-diameter portion 22 and an engagement surface 28 that is perpendicular to the annular surface 27 and faces the discharge side.

  On the inner peripheral surface of the metal housing 7, an annular convex portion 29 as a protruding portion is provided at a position corresponding to the annular step portion 26 of the discharge side case 20. The suction-side end surface of the resin housing 6 is abutted against the side surface of the annular convex portion 29 facing the discharge side by the pressing force of the caulking portion 19. Mainly due to this abutment, the space between the metal housing 7 and the resin housing 6 is sealed (sealed), and the leakage of fuel from between these is prevented.

  A small-diameter annular surface 27 of the annular step portion 26 is press-fitted into the inner peripheral surface of the annular convex portion 29. By this press-fitting, the space between the metal housing 7 and the discharge side case 20 is sealed, and the leakage of fuel from between these is prevented.

  The side surface on the suction side of the annular convex portion 29 abuts on the engagement surface 28 of the annular step portion 26. An end portion on the suction side of the metal housing 7 forms an annular caulking portion 30 that is caulked inward and engaged with a surface of the suction side case 21 facing the suction side. The suction-side case 21 and the discharge-side case 20 are sandwiched between the annular convex portion 29 and the caulking portion 30, and the end surfaces of both outer edge portions are sealed.

  A positioning convex portion 31 extending along the axial direction is provided on the inner peripheral surface on the suction side of the annular convex portion 29 of the metal housing 7. Correspondingly, a positioning groove that fits the positioning convex portion 31 of the metal housing 7 is provided from the outer peripheral surface of the suction-side case 21 to the outer peripheral surface of the large-diameter portion 22 of the discharge-side case 20.

  The positioning groove includes a positioning groove 32a on the suction side case 21 side and a positioning groove 32b on the discharge side case 20 side. The positioning convex portion 31 and the positioning grooves 32 a and 32 b define the positional relationship in the circumferential direction between the three of the metal housing 7, the discharge side case 20 and the suction side case 21.

  The suction side case 21 is provided with the fuel suction port 12 and an axial bearing 33 for bearing the suction side edge of the rotary shaft 8 in the axial direction.

  In assembling the fuel pump 1, an insulating resin material is used in advance, and the resin housing 6 is formed by insert molding using the stator core 2, the insulator 3a, the stator coil 3 and the terminal 13 as insert parts. Thereby, a stator assembly 34 in which these insert parts and the resin housing 6 are integrated is prepared.

  Next, the discharge side end of the metal housing 7 is press-fitted into the outer peripheral surface 18 of the suction side end of the resin housing 6. This press-fitting is performed until the suction side end surface of the resin housing 6 abuts against the annular convex portion 29 of the metal housing 7. Then, the caulking portion 19 is formed by caulking the discharge side end portion of the metal housing 7 toward the annular recess 17 side of the resin housing 6.

  Thereby, the resin housing 6 and the metal housing 7 are combined. Further, the resin housing 6 and the metal housing 7 are sealed (sealed) mainly by abutment with the annular convex portion 29 of the resin housing 6 to prevent fuel leakage.

  Next, the rotating shaft 8 of the rotor 4 is inserted into the radial bearing 14. Next, the discharge side case 20 is inserted into the metal housing 7, and the small-diameter annular surface 27 of the discharge side case 20 is press-fitted into the inner peripheral surface of the annular convex portion 29 of the metal housing 7.

  At the time of insertion and press-fitting, the positioning groove 32 b of the discharge side case 20 is guided by the positioning convex portion 31 of the metal housing 7, thereby defining the circumferential position of the discharge side case 20 with respect to the metal housing 7. Further, this press-fitting is performed until the engagement surface 28 of the discharge side case 20 comes into contact with the suction side surface of the annular convex portion 29. By this press-fitting, the space between the metal housing 7 and the discharge side case 20 is sealed (sealed), and fuel leakage is prevented.

  Further, when the discharge side case 20 is inserted into the metal housing 7, the vicinity of the suction side end of the rotary shaft 8 is inserted into the radial bearing 23 of the discharge side case 20.

  Next, the impeller 10 is inserted into the discharge side case 20 and fixed to the end of the rotary shaft 8. Next, the suction side case 21 is inserted into the metal housing 7. At the time of this insertion, the circumferential position of the discharge side case 20 relative to the metal housing 7 is defined by guiding the positioning groove 32 a of the suction side case 21 by the positioning convex portion 31 of the metal housing 7. At this time, the axial bearing 33 in the suction side case 21 is brought into contact with the suction side end of the rotary shaft 8.

  Next, an annular caulking portion 30 is formed by caulking the suction side end portion of the metal housing 7 toward the end surface of the suction side case 21 facing the suction side. Thus, the discharge side case 20 and the suction side case 21 are sandwiched between the annular convex portion 29 and the caulking portion 30 of the metal housing 7 and are firmly coupled to each other.

  In addition, as a result, the opposite end surfaces of the outer edge portions of the discharge-side case 20 and the suction-side case 21 are abutted against each other so that the fuel is not leaked, and a pump chamber that houses the impeller 10 is formed. Thereby, the assembly of the fuel pump 1 is completed.

  As described above, according to the present embodiment, the metal housing 7 covers the outer periphery of the pump unit 5 and is coupled to the resin housing 6 integrated with the stator core 2 on the pump unit 5 side with respect to the stator core 2. . For this reason, the part which covered the outer periphery of the stator core in the conventional metal housing is omissible. Thereby, the weight reduction, diameter reduction, and cost saving of the fuel pump 1 can be achieved.

  Further, since the outer periphery of the stator core 2 is covered with the resin housing 6, it is possible to prevent the fuel from leaking from the inside of the stator core 2 to the outside through the gap of the stator core 2.

  Further, since the metal housing 7 and the resin housing 6 are coupled by the caulking portion 19 of the metal housing 7, it is not necessary to use a member other than the metal housing 7 and the resin housing 6, and the metal housing 7 and the resin housing 6 are firmly coupled. can do.

  Further, since the suction side case 21 and the discharge side case 20 are sandwiched between the annular convex portion 29 and the caulking portion 30 of the metal housing 7, a large axial compressive force can be applied between them. Therefore, the end surfaces of the outer edge portions of the suction-side case 21 and the discharge-side case 20 are tightly pressed and sealed to maintain the fuel sealability.

  Further, since the resin housing 6 forms a cover that also covers the end of the stator core 2 opposite to the pump portion 5, it is not necessary to provide such a cover separately. For this reason, the number of parts constituting the fuel pump 1 can be reduced.

  FIG. 2 shows the structure of a fuel pump 40 according to another embodiment of the present invention. 2, the same reference numerals as those in FIG. 1 denote the same elements. As shown in FIG. 2, in the fuel pump 40, the resin housing 41 and the metal housing 42 are coupled by a snap fit.

  In order to realize this, the portion of the resin housing 41 that extends to the suction side from the stator core 2 is a small-diameter extending portion 43 that has a slightly smaller outer diameter than the portion that covers the stator core 2. The discharge side of the small diameter extending portion 43 covers and is integrated with the stator coil 3 and the insulator 3a. The suction side of the small diameter extending portion 43 constitutes a resin side press fitting portion 45 having an inner peripheral surface for press fitting the discharge side case 44 inward.

  The metal housing 42 includes a plurality of projecting pieces 47 extending from the discharge side end to the discharge side. The projecting piece 47 extends on the outer periphery of the small diameter extending portion 43 of the resin housing 41 and has a hole-shaped recess 46. The resin housing 41 has an engaging convex portion 48 corresponding to the hole-shaped concave portion 46 on the outer periphery of the small diameter extending portion 43.

  The projecting piece 47 and the engaging convex portion 48 constitute a snap fit mechanism. In addition, a convex part may be provided in the protrusion 47, and the recessed part corresponding to this may be provided in the resin housing 41, and a snap fit mechanism may be comprised.

  The discharge-side case 44 is provided with a case-side press-fit portion 50 having a slightly smaller outer diameter at the discharge-side end of the outer peripheral portion of the large-diameter portion 49. The case-side press-fit portion 50 is press-fit into the resin-side press-fit portion 45 of the resin housing 41. An engagement portion 51 formed by bending inward is provided at a portion other than the base end portion of the protruding piece 47 at the discharge side end portion of the metal housing 42.

  The engaging portion 51 is in contact with the engaging surface 28 that is the suction-side end surface of the case-side press-fit portion 50 and is formed at the suction-side end portion of the metal housing 42 as in the case of the annular convex portion 29 in FIG. In cooperation with the caulking portion 30, the end surfaces of the outer edge portions of the suction side case 21 and the discharge side case 44 are sealed. The other structure of the fuel pump 40 is the same as that of the fuel pump 1 of FIG.

  In assembling the fuel pump 40, the stator assembly 52 is formed by forming the resin housing 41 integrated with the stator core 2, the insulator 3 a, the stator coil 3, and the terminal 13 in the same manner as in the fuel pump 1 of FIG. 1. Is prepared. Next, the protruding piece 47 of the metal housing 42 is fitted to the outer periphery of the small diameter extending portion 43 of the resin housing 41, and the engaging convex portion 48 of the small diameter extending portion 43 is formed into the hole-shaped concave portion 46 of the protruding piece 47. Engage. Thereby, the resin housing 41 and the metal housing 42 are combined.

  Next, the rotating shaft 8 of the rotor 4 is inserted into the radial bearing 14. Next, the discharge side case 44 is inserted into the metal housing 42, and the case side press-fit portion 50 of the discharge side case 44 is press-fitted into the resin side press-fit portion 45 of the resin housing 41.

  During the insertion and press-fitting, the positioning groove 32b of the discharge side case 44 is guided by the positioning protrusion 31 of the metal housing 42, whereby the circumferential position of the discharge side case 44 with respect to the metal housing 42 is defined. The press-fitting is performed until the engagement surface 28 of the discharge side case 44 comes into contact with the engagement portion 51 of the metal housing 42. By this press-fitting, the resin housing 41 and the discharge-side case 44 are sealed (sealed), and fuel leakage is prevented.

  When the discharge side case 44 is inserted into the metal housing 42, the vicinity of the suction side end of the rotary shaft 8 is inserted into the radial bearing 23 of the discharge side case 44.

  Thereafter, the impeller 10 and the suction side case 21 are assembled in the same manner as in the case of the fuel pump 1 of FIG. As a result, a pump case 53 is formed in which the discharge side case 44 and the suction side case 21 are sandwiched between the engagement portion 51 and the caulking portion 30 of the metal housing 42 and sealed, and the pump portion 54 is completed. Thereby, the assembly of the fuel pump 40 is completed.

  According to the present embodiment, since the metal housing 42 and the resin housing 41 are coupled by the snap fit mechanism constituted by the plurality of projecting pieces 47 of the metal housing 42 and the engaging convex portion 48 of the resin housing 41, the metal housing The metal housing 42 and the resin housing 41 can be easily coupled without using members other than 42 and the resin housing 41.

  As mentioned above, although embodiment of this invention was described, this invention is not limited to this. For example, as the pump units 5 and 54, other types, for example, a spiral pump or a turbine pump may be adopted.

  Further, the insulator 3 a may not be provided between the stator coil 3 and the stator core 2 if the insulation between the stator coil 3 and the stator core 2 is ensured by the covering of the stator coil 3 or the like.

  Further, the fuel pumps 1 and 40 may be arranged in a fuel tank and used as an in-tank type fuel pump.

  DESCRIPTION OF SYMBOLS 1,40 ... Fuel pump, 2 ... Stator core, 3 ... Stator coil, 4 ... Rotor, 5, 54 ... Pump part, 6, 41 ... Resin housing, 7, 42 ... Metal housing, 3a ... Insulator, 8 ... Rotating shaft, DESCRIPTION OF SYMBOLS 9 ... Permanent magnet, 10 ... Impeller, 11, 53 ... Pump case, 12 ... Fuel inlet, 13 ... Terminal, 14 ... Radial bearing, 15 ... Fuel outlet, 16 ... Passage hole, 17 ... Annular recess, 18 ... Outer periphery Surface 19, caulking portion 20, discharge side case 21, suction side case 22, 49, large diameter portion 23, radial bearing 24, projecting cylindrical portion 25, gap 26, annular stepped portion 27, Small diameter annular surface, 28 ... engagement surface, 29 ... annular convex part, 30 ... caulking part, 31 ... positioning convex part, 32a, 32b ... positioning groove, 33 ... axial bearing, 34, 52 ... stator assembly, 4 DESCRIPTION OF SYMBOLS ... Fuel pump, 41 ... Resin housing, 42 ... Metal housing, 43 ... Small diameter extension part, 44 ... Discharge side case, 45 ... Resin side press-fit part, 46 ... Hole-shaped recessed part, 47 ... Projection piece, 48 ... Engagement convex part , 50: Case side press-fitting part, 51: Engaging part.

Claims (6)

A stator core;
A stator coil provided in the stator core for forming a rotating magnetic field on the inner peripheral side of the stator core;
A rotor disposed on the inner peripheral side of the stator core and rotated by the rotating magnetic field;
A pump unit that rotates integrally with the rotor, sucks fuel by rotation of the rotating member, and discharges the fuel to the rotor;
A resin housing formed integrally with the stator core by insert molding;
A fuel pump comprising a metal housing that covers an outer periphery of the pump portion and is coupled to an outer periphery of the resin housing on the pump portion side of the stator core.   The fuel pump according to claim 1, wherein the resin housing covers an outer periphery of the stator core. The resin housing has a step portion having a drop on the stator core side on the outer periphery on the pump portion side than the stator core,
The metal housing has a caulking portion joined to the step portion at an end portion on the stator core side,
The fuel pump according to claim 1 or 2, wherein the metal housing is coupled to an outer periphery of the resin housing by the caulking portion. The metal housing includes a plurality of projecting pieces extending to the outer periphery of the resin housing and having convex portions or concave portions,
On the outer periphery of the resin housing, a concave portion or a convex portion that engages with a convex portion or a concave portion of each protruding piece is provided,
3. The fuel pump according to claim 1, wherein the plurality of projecting pieces and a concave portion or a convex portion of the resin housing constitute a snap fit mechanism that couples the metal housing to an outer periphery of the resin housing. The pump section includes a pump case on the suction side and a pump case on the discharge side,
The suction-side and discharge-side pump cases have end surfaces of these outer edge portions in axial contact with each other to form a pump chamber inside,
The pump case on the discharge side is provided with an engagement surface facing the stator core side,
The metal housing is
A protrusion that protrudes inward from the inner peripheral surface of the metal housing and contacts the engagement surface;
A caulking portion that is provided at an end of the metal housing opposite to the stator core and is joined to the pump case on the suction side by caulking;
The fuel pump according to any one of claims 1 to 4, wherein the suction-side and discharge-side pump cases are sandwiched between the projecting portion and the caulking portion, and the end surfaces are hermetically sealed.   The fuel pump according to any one of claims 1 to 5, wherein the resin housing forms a cover that covers an end portion of the stator core opposite to the pump portion.