JP2005194894A - Fuel pump - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fuel pump capable of preventing the output efficiency of a motor part from being lowered while preventing corrosion and electrical troubles from occurring due to the invasion of a fluid to a stator part. <P>SOLUTION: This fuel pump comprises a rotor part 11 installed rotatably about a pivot shaft, a motor part 10 having a stator part 12 having a plurality of tooth faces 17b disposed oppositely to each other through a distance in the circumferential direction of the rotor part 11 and acting electromagnetic force on the rotor part 11, a motor part 10 fixed to the stator part 12 and having a partition wall body 3 partitioning the clearance thereof from the rotor part 11 in a liquid-sealed state, and a pump part driven by the rotation of the rotor part 11 of the motor part 10 and discharging a fuel sucked from a fuel sucking passage from a fuel discharge passage. The partition wall body 3 is so formed that all areas opposed to the tooth faces 17b are formed in a magnetic composition part 31 and all areas opposed to a slit 17c between the adjacent tooth faces 17b are formed in a non-magnetic composition part 32, and the magnetic composition part 31 and the non-magnetic composition part 32 are alternately arranged in the circumferential direction. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a fuel pump for supplying fuel in a fuel tank to, for example, an internal combustion engine.

  Conventionally, various fuel pumps have been proposed. Patent Document 1 discloses a fuel pump as an example.

  As shown in FIG. 12, the fuel pump 100 has a cylindrical case 101, two side wall housings 102 and 103 arranged so as to close both ends of the cylindrical case 101, and one end side supported by the one side wall housing 102. The motor unit 106 and the pump unit 107 are provided around the support shaft 104 and at different positions in the axial direction.

  The motor unit 106 includes a rotor unit 109 that is rotatably supported by a support shaft 104 via a bearing 108, a stator unit 110 that is disposed at an outer peripheral position from the rotor unit 109, and that is disposed to face the rotor unit 109. A partition wall 111 is fixed to the stator portion 110 side and partitions the rotor portion 109 in a liquid-tight state.

  The rotor portion 109 is composed of a yoke 109a and a magnet portion 109b. The stator portion 110 includes an iron core 110 a having tooth surfaces arranged at intervals in the circumferential direction and a winding 110 b wound around the iron core 110 a, and a plurality of tooth surfaces are arranged to face the rotor portion 109. Has been. An electromagnetic force is applied to the rotor portion 109 by generating a predetermined magnetic field from the tooth surface of the excited iron core 110a.

  The partition body 111 has a cylindrical shape with one end closed, and is disposed between the rotor portion 109 and the stator portion 110. The other end side of the support shaft 104 is supported by the recess 111 a of the partition wall 111.

  The pump unit 107 includes one side wall housing 102 and an upper housing 121 disposed via a spacer 120, and an inner rotor 123 can freely rotate around the support shaft 104 in a pump chamber 122 surrounded by these members. Is provided. One side wall housing 102 is formed with a fuel suction passage 124 and a fuel discharge passage 125 that open to the pump chamber 122. The inner rotor 123 is connected to the rotor portion 109 of the motor portion 106 via a joint member 126, and is driven to rotate in the pump chamber 122 by the rotation of the rotor portion 109.

  In the above configuration, when the stator unit 110 is energized, a predetermined magnetic field is generated from the stator unit 110 in the rotor unit 109, and an electromagnetic force acts on the rotor unit 109. This electromagnetic force causes the rotor portion 109 to rotate about the support shaft 104, and the rotation of the rotor portion 109 causes the inner rotor 123 of the pump portion 107 to rotate. When the inner rotor 123 rotates, fuel is sucked into the pump chamber 122 from the fuel suction passage 124, and the sucked fuel is discharged from the fuel discharge passage 125. The fuel discharged from the fuel discharge passage 125 is supplied to the internal combustion engine.

In the fuel pump 100 driven in this way, the fuel flows out to the rotor unit 109 side of the motor unit 106 due to the fluid properties of the fuel, the pressure of the pump unit 107, and the like. Is prevented from being immersed in the stator portion 110 by the partition wall 111. On the stator 110 side, windings 110b and electronic parts for energizing the windings 110b are arranged, and the partition wall 111 prevents them from being corroded by fuel or causing electrical troubles. it can.
JP-A 63-176686

  However, in the fuel pump 100, the partition body 111 is formed of a non-magnetic metal (for example, SUS). Therefore, the air gap dimension between the stator portion 110 and the rotor portion 109 is equal to the thickness of the partition body 111, The size is a combination of the partition wall 111 and the gap between the rotor portion 109. Therefore, since the substantial air gap dimension between the stator part 110 and the rotor part 109 is larger by the thickness than the case where the partition body 111 is not attached, the motor part 106 is compared with the motor part where the partition body 111 is not attached. There was a problem that the output efficiency was lowered.

  On the other hand, if the partition body 111 is made of a magnetic material, a magnetic circuit passing through the rotor portion 109 obtained by magnetically blocking by the slits between adjacent tooth surfaces of the stator portion 110 cannot be formed, and the partition body 111 itself An eddy current is generated. Therefore, when the partition wall 111 is formed of a magnetic material, the output efficiency of the motor unit 106 is greatly reduced as compared with a motor unit without the partition wall 111 attached.

  The present invention has been made in view of the above-described circumstances, and an object of the present invention is to reduce the output efficiency of the motor unit while preventing corrosion and electrical problems caused by the immersion of fluid in the stator unit side. It is an object of the present invention to provide a fuel pump that can prevent the above.

  In order to achieve the above object, according to the first aspect of the present invention, a rotor portion and a plurality of tooth surfaces are arranged opposite to each other at intervals in the circumferential direction of the rotor portion, and electromagnetic force is applied to the rotor portion. A motor unit having a stator unit to be actuated, a partition body partitioning the stator unit and the rotor unit in a sealed state, and a motor driven by the rotation of the rotor unit of the motor unit to discharge fuel sucked from the fuel suction passage In the fuel pump including the pump unit that discharges from the passage, the partition body includes at least a part of a region facing each tooth surface as a magnetic composition part, and a part other than the magnetic composition part as a non-magnetic part. It is intended that each of the magnetic composition portions and the nonmagnetic composition portions is alternately arranged in the circumferential direction.

  The invention according to claim 2 is the fuel pump according to claim 1, wherein the magnetic composition portion is in the entire region facing each tooth surface, and the non-magnetic composition portion is between the adjacent tooth surfaces. It is the structure each arrange | positioned in the whole area | region facing a slit.

  Further, the invention according to claim 3 is the fuel pump according to claim 1 or 2, wherein the gap between the partition wall and the rotor is formed in a fluid passage through which fuel passes.

  According to the first aspect of the present invention, since the magnetic composition portion of the partition wall functions as a tooth surface of the stator portion, a substantial air gap between the stator portion and the rotor portion can be surely reduced. Since the magnetic composition portion secures magnetic shielding between the tooth surfaces of the stator portion, a desired magnetic circuit can be formed between the stator portion and the rotor portion. Furthermore, since the partition body has alternating magnetic composition portions and non-magnetic composition portions and can divide eddy currents generated in the partition body itself, magnetic loss due to eddy currents can be reliably prevented. As a result, it is possible to prevent a reduction in output efficiency of the motor unit while preventing corrosion and electrical damage caused by the fluid being immersed in the stator unit side.

  In addition, since the magnetic composition part of each partition body functions as a tooth surface of the stator part and the nonmagnetic composition part functions as a slit between the tooth surfaces of the stator, the alignment ratio and position of the magnetic composition part and the nonmagnetic composition part of the partition body Etc., or skew-like adjustment, and fine magnetic performance matching is possible. Therefore, by changing only the partition wall, it is possible to easily manufacture a motor unit having optimum output characteristics suitable for the purpose of use.

  According to the invention of claim 2, since the magnetic composition part of the partition wall becomes a substantial tooth surface of the stator part, the motor part has the same air gap as the motor part not provided with the partition wall, and the output efficiency of the motor part As a result, it is possible to obtain almost the same output efficiency as that without the partition wall.

  According to the invention of claim 3, since the fuel passes between the rotor portion and the stator portion, heat generation of the rotor portion and the stator portion can be reliably prevented. Further, the fuel suction passage and the fuel discharge passage can be separately arranged on one end side where the pump portion is disposed with respect to the motor portion and on the other end side where the pump portion is not disposed. That is, the fuel pump can be installed when the fuel suction passage and the fuel discharge passage cannot be arranged at the same position due to the installation space of the fuel pump.

(First embodiment)
Hereinafter, a first embodiment of the present invention will be described with reference to the drawings.

  1 is a cross-sectional view of a fuel pump, FIG. 2 is a cross-sectional view before assembling a rotor part and a pump part to a partition body assembled with a stator part, FIG. 3 is an exploded perspective view of a main part of a motor part, and FIG. It is sectional drawing which shows the arrangement | positioning state of a partition body and a rotor part.

  1 and 2, the fuel pump 1 has a pump frame 2. The pump frame 2 is formed by a deep drawing process from a partition body 3 and a case portion 4 integrally formed on the outer periphery of the partition body 3. Has been.

  The partition wall 3 has a three-step cylindrical shape having an open bottom surface and a closed top surface. Due to the three-stage cylindrical shape, a three-stage columnar space whose diameter is reduced from the bottom surface side toward the upper surface side is formed inside the partition wall 3, and the innermost portion of the three-stage columnar space is an axis. The support portion 3a, the central portion is formed as the rotor chamber 3b, and the inlet portion is formed as the pump fitting portion 3c. The case portion 4 has a cylindrical shape that further surrounds the outer periphery of the partition wall 3, and a space between the partition wall 3 and the case portion 4 is formed in the stator housing chamber 5. And the motor part 10 and the pump part 20 are integrally assembled | attached to this pump frame 2. As shown in FIG.

  The motor unit 10 includes a rotor unit 11 that is rotatably disposed in the rotor chamber 3b, and a stator unit 12 that is disposed in a fixed state in the stator housing chamber 5. The rotor unit 11 and the stator unit 12 are The partition wall 3 partitions the liquid-tight state. The partition body 3 is fixed to the stator 12 side.

  The rotor portion 11 is composed of a cylindrical magnet yoke 13 and a cylindrical magnet 14 fixed to the outer periphery of the magnet yoke 13, and rotates on the outer periphery of the support shaft 15 via a pair of bearing portions 16 and 16. It is supported freely. One end of the support shaft 15 is supported by the shaft support 3 a of the partition wall 3, and the other end is supported by the pump unit 20. The bearing portion 16 is constituted by, for example, a ball bearing.

  The stator portion 12 includes an iron core 17 having radial branch portions 17a at equal intervals in the inner peripheral radial direction, windings 18 wound around the radial branch portions 17a of the iron core 17, and a resin filled in the outer periphery thereof. A block body is formed from the portion 19 and the like. The distal end surface of each radial branch portion 17a of the iron core 17 is formed as a tooth surface 17b of the stator portion 12, respectively. The plurality of tooth surfaces 17b are arranged to face each other at intervals in the circumferential direction of the rotor portion 11, and an electromagnetic force is applied to the rotor portion 11 by generating a predetermined magnetic field.

  The pump part 20 is fitted in the pump fitting part 3 c, and the rotor chamber 3 b is substantially sealed by the pump part 20. The other end side of the support shaft 15 is fixed to the pump unit 20, and the support shaft 15 is supported by the pump frame 2 via the pump unit 20. The pump unit 20 includes a lower plate body 21, a ring body 22 disposed on the upper surface of the lower plate body 21, and an upper plate body 23 disposed on the upper surface of the ring body 22, which are screws 24. It is fixed integrally by. Inside these, a pump chamber 25 is formed. The support shaft 15 passes through the pump chamber 25, and an inner peripheral gear 26 and an outer peripheral gear 27, which are pump rotors, are rotatably accommodated. Yes.

  The inner peripheral gear (pump rotor) 26 is rotatably arranged around the support shaft 15 and on the outer periphery of the support shaft 15. The outer peripheral gear (pump rotor) 27 is disposed so as to be rotatable about the center point of the ring body 22 and along the inner peripheral surface of the ring body 22. That is, the inner peripheral gear 26 and the outer peripheral gear 27 are arranged in an eccentric position and meshed with each other, and the suction (low pressure) area and the discharge (high pressure) are supplied to the pump chamber 25 by the rotation of the gears 26 and 27. An area is formed.

  A fuel suction passage 28 and a fuel discharge passage 29 are respectively formed in the lower plate body 21. The fuel suction passage 28 has one end opened to the suction area of the pump chamber 25 and the other end connected to a pipe (not shown) in the fuel tank. The fuel discharge passage 29 has one end opened to the discharge area of the pump chamber 25 and the other end connected to a pipe (not shown) led to the internal combustion engine.

  The joint member 30 has a substantially cylindrical shape, and is rotatably disposed on the outer periphery of the support shaft 15 between the motor unit 10 and the pump unit 20. The upper and lower ends of the joint member 30 are connected to the rotor portion (motor rotor) 11 and the inner peripheral gear (pump rotor) 26 in a state where the rotation direction is restricted, and the rotor portion 11 is connected via the joint member 30. Is transmitted to the inner peripheral gear 26.

  On the other hand, as shown in FIGS. 3 and 4, the partition body 3 has the entire surface of the region facing each tooth surface 17b of the stator portion 12 as the magnetic composition portion 31 and the slit 17c between the adjacent tooth surfaces 17b. The entire surface of the opposing region, that is, the part other than each magnetic composition part 31 is formed in the nonmagnetic composition part 32 by the composition deformation process, and the magnetic composition part 31 and the nonmagnetic composition part 32 are alternately arranged in the circumferential direction. ing. The magnetic composition part 31 is formed ferromagnetic. In FIG. 3 and FIG. 4, the magnetic composition portion 31 is illustrated in a multipoint pattern for clarity.

  Next, the operation of the fuel pump 1 will be described. When the stator portion 12 is energized, a predetermined magnetic field is generated from the stator portion 12 in the rotor portion 11, and electromagnetic force acts on the rotor portion 11. Due to this electromagnetic force, the rotor portion 11 rotates about the support shaft 15, and this rotation is transmitted to the inner peripheral gear 26 via the joint member 30, whereby the inner peripheral gear 26 and the outer peripheral gear 27 are moved inside the pump chamber 25. Rotate. The rotation of the inner peripheral gear 26 and the outer peripheral gear 27 causes the fuel to be sucked into the pump chamber 25 from the fuel suction passage 28, and the sucked fuel is discharged from the fuel discharge passage 29.

  In the operation of the motor part 10 described above, the magnetic composition part 31 of the partition wall 3 functions as the tooth surface 17b of the stator part 12, so that the substantial air gap between the stator part 12 and the rotor part 11 is reliably reduced. In addition, since the nonmagnetic composition portion 32 of the partition wall 3 secures magnetic shielding between the tooth surfaces 17 b of the stator portion 12, a desired magnetic circuit can be formed between the stator portion 12 and the rotor portion 11. Furthermore, since the magnetic body 31 and the nonmagnetic composition portion 32 are alternately arranged in the partition body 3 and the eddy current generated in the partition body 3 itself can be divided, magnetic loss due to the eddy current can be reliably prevented. As a result, it is possible to prevent the output efficiency of the motor unit 10 from being reduced while preventing corrosion and electrical damage caused by the fluid being immersed in the stator unit 12 side.

  Moreover, since the magnetic composition part 31 of each partition body 3 functions as the tooth surface 17b of the stator part 12, and the nonmagnetic composition part 32 functions as the slit 17c between the tooth surfaces 17b of the stator part 12, the magnetic composition part of the partition body 3 It is possible to adjust the alignment ratio and position of the nonmagnetic composition portion 32 and the nonmagnetic composition portion 32, or to adjust the skew, and fine magnetic performance matching is possible. Therefore, by changing only the partition wall 3, the motor unit 10 having the optimum output characteristics suitable for the purpose of use can be easily manufactured.

  In the first embodiment, the magnetic composition portion 31 is disposed in the entire region facing each tooth surface 17b, and the non-magnetic composition portion 32 is disposed in the entire region facing the slit 17c between the adjacent tooth surfaces 17b. Since the magnetic composition part 31 of the partition body 3 becomes a substantial tooth surface of the stator part 12, the motor part 10 has the same air gap as the motor part not provided with the partition body 3, and the output efficiency of the motor part 10 is reduced. The output efficiency almost equivalent to that without 3 can be obtained. The partition body 3 is configured such that at least a part of a region facing each tooth surface 17b is formed in the magnetic composition part 31, and a part other than each magnetic composition part 31 is formed in the nonmagnetic composition part 32, respectively. Also good.

  In the above-described embodiment, the partition body 3 is configured to support the support shaft 15 and the stator portion 12, so that both the rotor portion 11 and the stator portion 12 are positioned with reference to only the partition body 3. Therefore, it is possible to easily align both axes.

  In the above embodiment, since the partition body 3 integrally includes the case portion 4 that covers the outer periphery of the stator portion 12, it is not necessary to manufacture the case portion 4 separately from the partition body 3. It will reduce man-hours.

  In the above embodiment, since the magnetic composition portion 31 of the partition wall 3 is ferromagnetic, it can be prevented from reducing the magnetic field strength from the stator portion 12 to the rotor portion 11, thereby preventing reduction in output efficiency of the motor portion 10. can do.

  FIG. 5 is a cross-sectional view of the main part showing a modification of the tooth surface of the iron core.

  The tooth surface 17b of the iron core 17 of the first embodiment is formed as a flat surface, and the partition wall 3 is in close contact with the tooth surface 17b only at one point. In this modification, the tooth surface 17b of the iron core 17 is an arc surface. The partition wall 3 as a whole is in close contact with the tooth surface 17b. In FIG. 5, the same components as those in the first embodiment are denoted by the same reference numerals, and the description thereof is omitted.

  According to this modification, since no air gap is generated between the iron core 17 and the magnetic composition part 31 of the partition wall body 3, magnetic loss between the iron core 17 and the partition wall body 3 can be eliminated.

  6A and 6B are perspective views showing modifications of the partition wall body 3, respectively.

  The partition wall body 3 of the first embodiment is formed in a cylindrical shape, and the partition wall body 3 is in close contact with the tooth surface 17b of the iron core only at one point. In the modification shown in FIG. The three magnetic composition parts 31 and the nonmagnetic composition parts 32 are alternately arranged in the circumferential direction with a skew.

  Moreover, in the modification shown in FIG.6 (b), the partition body 6 is formed in polygonal shape. In the partition wall 6, even when the tooth surface 17 b of the iron core 17 is a flat surface, the entire surface of the partition wall 6 is in close contact with the tooth surface 17 b of the iron core 17.

  Therefore, since no air gap is generated between the iron core 17 and the magnetic composition part 31 of the partition wall body 6, magnetic loss between the iron core 17 and the partition wall body 6 can be eliminated.

(Second Embodiment)
Hereinafter, a second embodiment of the present invention will be described with reference to the drawings.

  7 to 9 show a second embodiment, FIG. 7 is a cross-sectional view of the fuel pump, FIG. 8 is a cross-sectional view before assembling the rotor part and the pump part to the partition body assembled with the stator part, and FIG. FIG.

  7 to 9, the pump frame 2A of the fuel pump 1A is configured integrally with the partition body 3A and the case portion 4A as in the first embodiment. The pipe portion 40 is integrally formed on the side where it is not disposed, that is, on the upper surface side of the partition wall 3A. Further, only the fuel suction passage 28 is provided in the lower plate body 21, and fuel is discharged from the fuel communication passage 41 of the upper plate body 23 to the rotor portion 11 side. Further, a gap between the partition wall 3A and the rotor portion 11 is formed as a fluid passage 42 through which fuel passes, and an inside of the pipe portion 40 connected above the fluid passage 42 is formed as a fuel discharge passage 43. ing.

  In addition, a caulking portion 44 is formed by caulking the upper end portion of the case portion 4 </ b> A, and the stator portion 12 is fixed to the stator housing chamber 5 by the caulking portion 44.

  Since the other configuration other than the above is the same as that of the first embodiment, the same components are denoted by the same reference numerals and the description thereof is omitted.

  According to this configuration, since the fuel passes between the rotor portion 11 and the stator portion 12, heat generation of the rotor portion 11 and the stator portion 12 can be reliably prevented. Further, the fuel suction passage 28 and the fuel discharge passage 43 can be separately arranged on the lower end side where the pump portion 20 of the fuel pump 1B is arranged and the upper end side where the pump portion 20 is not arranged. That is, the fuel pump 1A can be installed even when the fuel suction passage 28 and the fuel discharge passage 43 cannot be arranged at the same position due to the installation space of the fuel pump 1A. Further, since the pipe portion 40 is integrally formed with the partition wall 3A, it is not necessary to separately arrange the pipe, so that the number of parts and the number of assembling steps can be reduced.

(Third embodiment)
Hereinafter, a third embodiment of the present invention will be described with reference to the drawings.

  10 and 11 show a second embodiment, FIG. 10 is a cross-sectional view of the fuel pump, and FIG. 11 is a cross-sectional view before the rotor portion and the pump portion are assembled to the pump frame.

  10 and 11, in the pump frame 2B of the fuel pump 1B, unlike the first and second embodiments, the partition wall body 3B and the case portion 4B are configured as separate members, and the separate partition wall body 3B and the case The part 4B is bonded. Since other configurations are the same as those of the second embodiment, the same reference numerals are given to the same components in the drawings, and description thereof will be omitted.

  According to this configuration, the pump frame 2B can be manufactured by deep drawing which is easier than that of the second embodiment. For this reason, the whole manufacturing cost can be reduced.

  Further, technical ideas other than the claims that can be grasped from the above embodiment will be described together with the effects thereof.

  (B) The fuel pump according to any one of claims 1 to 3, wherein the partition wall is configured to support the support shaft and the stator portion.

  According to this configuration, since both the rotor portion and the stator portion are positioned with reference to only the partition wall, the axial alignment of both can be facilitated.

  (B) The fuel pump according to any one of claims 1 to 3 and (a), wherein the partition wall body integrally includes a case portion covering the outer periphery of the stator portion.

  According to this configuration, it is not necessary to manufacture the case part separately from the partition wall, so that the number of parts, the number of assembly steps, and the like are reduced.

  (C) The fuel pump according to any one of claims 1 to 3, and (a) and (b) above, wherein the magnetic composition part of the partition body is ferromagnetic.

  According to this configuration, it is possible to prevent the magnetic field intensity from the stator portion to the rotor portion from being reduced, and thus it is possible to reliably prevent the output efficiency of the motor portion from being reduced.

  (D) The fuel pump according to any one of claims 1 to 3 and (a) to (c), wherein the partition wall and the tooth surface of the stator portion are configured to be in close contact with each other. A fuel pump characterized by

  According to this configuration, since no air gap is generated between the iron core and the magnetic composition of the partition wall, the magnetic loss between the iron core and the partition wall can be reliably eliminated.

  (E) The fuel pump according to claim 3 or (a) to (d) above, wherein the partition wall is integrally formed with a pipe portion.

  According to this configuration, since it is not necessary to connect a pipe separately, the number of parts is reduced, and the number of assembling steps is reduced.

1 is a cross-sectional view of a fuel pump according to a first embodiment of the present invention. It is sectional drawing before attaching a rotor part and a pump part to the partition body which showed 1st Embodiment of this invention and attached the stator part. It is a disassembled perspective view of the principal part of a motor part which shows 1st Embodiment of this invention. It is sectional drawing which shows 1st Embodiment of this invention and shows the arrangement | positioning state of a stator part, a partition body, and a rotor part. The modification of the iron core of 1st Embodiment of this invention is shown, and it is sectional drawing of a stator part, a partition body, and a rotor part. (A), (b) is a perspective view which shows each modification of the partition body of 1st Embodiment of this invention, respectively. FIG. 3 is a cross-sectional view of a fuel pump according to a second embodiment of the present invention. It is sectional drawing before attaching a rotor part and a pump part to the partition body which showed 2nd Embodiment of this invention and attached the stator part. It is a perspective view of a partition body showing a second embodiment of the present invention. FIG. 4 is a sectional view of a fuel pump according to a third embodiment of the present invention. It is sectional drawing before assembling a rotor part and a pump part to a partition body, showing 3rd Embodiment of this invention. It is sectional drawing of the fuel pump of a prior art example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1,1A, 1B Fuel pump 2,2A, 2B Pump frame 3,3A, 3B Partition body 4,4A, 4B Case part 10 Motor part 11 Rotor part 12 Stator part 15 Support shaft 17b Tooth surface 17c Slit 20 Pump part 28 Fuel Suction passage 29 Fuel discharge passage 31 Magnetic composition part 32 Non-magnetic composition part

Claims (3)

A rotor portion rotatably provided around a support shaft, a plurality of tooth surfaces facing each other at intervals in the circumferential direction of the rotor portion, and a stator portion that applies electromagnetic force to the rotor portion; A motor part that is fixed to the stator part side and has a partition wall that partitions the rotor part in a sealed state, and a fuel that is driven by the rotation of the rotor part of the motor part and sucked from the fuel suction passage. In a fuel pump provided with a pump part for discharging more,
In the partition body, at least a part of a region facing each tooth surface is formed in the magnetic composition part, and a part other than the magnetic composition part is formed in the non-magnetic composition part. The fuel pump is characterized in that the portions are alternately arranged in the circumferential direction.   The said magnetic composition part is arrange | positioned in the all area | region facing each said tooth surface, and the said nonmagnetic composition part is each arrange | positioned in the all area | region facing the slit between the said adjacent tooth surfaces. Fuel pump. The fuel pump according to claim 1 or 2, wherein a gap between the partition wall and the rotor is formed in a fluid passage through which fuel passes.

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