JP2017166459A - Fuel filter and fuel pump module - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fuel filter that suppresses the number of components to the minimum to improve assembly efficiency while enabling replacement of a filter unit.SOLUTION: The fuel filter 11 includes: a first housing half body 13 having a male-side cylindrical body 15 for receiving a filter unit 33, and a first connection pipe 16; a second housing half body 14 having a female-side cylindrical body 22 for receiving the male-side cylindrical body 15, and a second connection pipe 23; and a snap-fit mechanism 28 having a claw 31 mutually engaging with a step 29 defined in an engagement piece 27 to regulate axial displacement of the male-side cylindrical body 15 relative to the female-side cylindrical body 22.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a fuel filter and a fuel pump module.

  Patent document 1 discloses a fuel filter. The fuel filter includes a housing and a lid. The lid closes the open end of the housing. Thus, the filter element (filter unit) is accommodated in the accommodating space defined by the lid and the housing.

Special table 2014-505822 gazette

  A nut member is coupled to the open end of the housing for fixing the lid. The thread groove of the nut member meshes with the thread groove on the outer surface of the housing. The nut member is screwed while engaging with the flange of the lid and presses the lid against the open end of the housing. A seal member is sandwiched between the lid and the housing for ensuring the sealing property. Although the filter element can be removed without destroying the housing, lid, or nut member, the threaded groove is formed while maintaining the strength, so the radial dimension of the fuel filter increases and the number of parts is increased. And the assembly work is troublesome.

  An object of the present invention is to provide a fuel filter and a fuel pump module that can reduce the number of parts and increase the assembly efficiency while realizing replacement of the filter unit.

  According to the first aspect of the present invention, a filter unit, a male cylindrical body that defines a first space that receives the filter unit at least partially from an open end, and a flow passage that extends from the first space are defined. A first housing half having a first connecting pipe at a closed end; a female cylinder defining a second space for receiving the male cylinder in the first direction from the open end; and a flow extending from the second space. A second housing half having a second connecting pipe defining a path at the closed end, and an elastically deformable engagement piece extending from the female side cylindrical body along the outer periphery of the male side cylindrical body in the direction of the generatrix, An axis of the female cylindrical body with respect to the male cylindrical body in a second direction opposite to the first direction by engaging a claw partitioned on the outer periphery with a step divided by the engaging piece. Snack that regulates directional displacement Fuel filter and a fitting mechanism is provided.

  According to the second aspect, in addition to the configuration of the first side surface, the fuel filter includes an annular seal sandwiched between the outer peripheral surface of the male side cylindrical body and the inner peripheral surface of the female side cylindrical body.

  According to the third aspect, in addition to the configuration of the second side surface, the inner peripheral surface has a first inward cylindrical surface that receives the annular seal and a larger diameter than the first inward cylindrical surface, A second inward cylindrical surface continuous to the inner surface of the engagement piece, and the second inward cylindrical surface connected to the first inward cylindrical surface, and the second inward cylinder from the first inward cylindrical surface. And a tapered surface gradually spreading toward the surface.

  According to the fourth aspect, in addition to the configuration of the third side face, the fuel filter is formed at the open end of the male side cylindrical body and abuts against the second housing half body in a plane perpendicular to the central axis. And an abutting surface for restricting axial displacement of the female cylindrical body in the first direction and an outer peripheral surface of the male cylindrical body, and the abutting surface abuts against the second housing half An outwardly facing cylindrical surface that faces the first inwardly cylindrical surface when received, and is connected to an end of the outwardly facing cylindrical surface that is far from the open end, and is orthogonal to the central axis. An axial direction of the annular seal when the abutting surface is abutted against the second housing half and is connected to the first radial surface that extends radially outward in a plane and the first inward cylindrical surface Toward the first radial surface at intervals greater than the dimension. And a second radial plane to fit.

  According to the fifth aspect, the female cylinder that receives the fuel pump in the first direction from the open end and partitions the space for accommodating the filter unit between the end surface of the fuel pump, and the flow passage extending from the space are defined. A housing having a connecting pipe at the closed end, an elastically deformable engagement piece extending from the housing along the outer periphery of the fuel pump in the direction of the bus, and a step defined by the engagement piece on the outer periphery. A fuel pump module is provided that includes a snap-fit mechanism that engages the divided claws and restricts the axial displacement of the female cylindrical body with respect to the fuel pump in a second direction opposite to the first direction. Is done.

  According to the first aspect, when the first housing half and the second housing half are joined, the male cylindrical body is fitted into the female cylindrical body, and at least partially overlaps the first space and the second space of the filter unit. A storage space is defined. The snap fit mechanism prevents the male cylinder from coming off from the female cylinder. Thus, the coupling of the first housing half and the second housing half is maintained. Since the engagement between the claw and the step is released according to the elastic deformation of the engagement piece, the first housing half and the second housing half can be separated without breaking. Thus, the filter unit can be taken out and cleaned, or replaced with a new filter unit. In addition, the claw need only be related to the step of the engaging piece, and does not need to protrude radially outward from the engaging piece. Therefore, the radial dimension of the fuel filter can be suppressed. Since the engaging piece and the snap-fit mechanism are integrated into the first housing half or the second housing half, the number of parts is minimized, the assembly efficiency is increased, and the possibility of parts being lost is significantly reduced. Certain work can be realized even in a poor environment.

  According to the second aspect, since the annular seal is sandwiched between the male side cylindrical body and the female side cylindrical body, the seal is reliably ensured between the male side cylindrical body and the female side cylindrical body.

  According to the third aspect, when the male cylindrical body is fitted into the female cylindrical body when the first housing half and the second housing half are coupled, the inner surface of the engagement piece and the second inward cylindrical surface are Pass the annular seal. Thereafter, the pressing force of the annular seal gradually increases from the tapered surface toward the first inward cylindrical surface. Therefore, excessive force does not act on the annular seal, and damage to the annular seal can be avoided.

  According to the fourth aspect, when the claw engages with the step by the snap fit mechanism, the displacement of the male cylindrical body in the first direction is restricted by the abutment of the abutment surface. At this time, the annular seal is sandwiched between the first inward cylindrical surface and the outward cylindrical surface. If the annular seal is previously mounted on the outer periphery of the male cylinder, the annular seal is received on the first radial surface in the axial direction during the relative movement of the male cylinder. Since the second radial surface faces the first radial surface at an interval larger than the axial dimension of the annular seal, the annular seal is prevented from being crushed. The pressing surface appropriately maintains the clearance necessary for the snap-fit mechanism and contributes to suppression of unnecessary rattling.

  According to the fifth aspect of the invention, the fuel pump is fitted into the female cylinder when the housing is attached to the fuel pump. The housing defines an accommodation space for the filter unit between the end face of the fuel pump. The snap fit mechanism prevents the fuel pump from coming off the female cylinder. Therefore, the connection between the housing and the fuel pump is maintained. Since the engagement of the claw and the step is released according to the elastic deformation of the engagement piece, the housing and the fuel pump can be separated without breaking. Thus, the filter unit can be taken out and cleaned, or replaced with a new filter unit. In addition, the claw need only be related to the step of the engaging piece, and does not need to protrude radially outward from the engaging piece. Therefore, the radial dimension of the housing can be suppressed. Engagement pieces and snap-fit mechanisms are integrated into the housing or fuel pump, minimizing the number of parts, increasing assembly efficiency, significantly reducing the possibility of missing parts, and ensuring even in harsh environments The work can be realized.

It is a perspective view showing roughly the appearance of the fuel filter concerning a 1st embodiment. It is a vertical sectional view of a fuel filter. It is a vertical sectional view which shows roughly the whole structure of the fuel pump module concerning a 2nd embodiment.

  Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings.

  FIG. 1 shows an appearance of a fuel filter 11 according to the first embodiment. The fuel filter 11 includes a housing 12. The housing 12 includes a first housing half 13 and a second housing half 14. The first housing half 13 has a male cylindrical body 15. A first connection pipe 16 is formed at the closed end of the male side cylinder 15. Connected to the first connection pipe 16 is a fuel pipe 19 leading to a fuel injection valve 18 of the internal combustion engine 17. For example, a fuel pump 21 is disposed in the fuel pipe 19 between the fuel injection valve 18 and the fuel filter 11.

  The second housing half 14 has a female cylindrical body 22. A second connection pipe 23 is formed at the closed end of the female side cylindrical body 22. A fuel pipe 25 leading to the fuel tank 24 is connected to the second connection pipe 23. The fuel is introduced into the fuel filter 11 from the second connection pipe 23 by the action of the fuel pump 19 (or the pressure difference due to gravity), and the fuel flows out from the first connection pipe 16. The male side cylinder 15 is fitted into the female side cylinder 22.

  The second housing half 14 has a plurality of engaging pieces 27. The engaging piece 27 extends from the open end of the female cylinder 22 along the outer periphery of the male cylinder 15 in the direction of the bus. The engaging pieces 27 may be arranged at equal intervals in the circumferential direction around the central axis Xis of the female cylindrical body 22. Alternatively, the number of the engagement pieces 27 may be one, and the engagement pieces 27 may be arranged so as to be biased to a specific central angle range.

  A snap fit mechanism 28 is constructed between the first housing half 13 and the second housing half 14. The snap fit mechanism 28 includes a step 29 defined by the engaging piece 27 and a claw 31 defined on the outer periphery of the male cylindrical body 15 for each engaging piece 27. A window hole 32 is formed in each engaging piece 27 when the step 29 is divided. The window hole 32 weakens the bending rigidity of the engaging piece 27 and gives an elastic restoring force to the engaging piece 27. In this way, the engaging piece 27 is configured to be elastically deformable in the radial direction of the male cylindrical body 15. The claw 31 is received in the window hole 32. The male cylinder 15 is received by the female cylinder 22 in the first direction DR1 from the open end of the female cylinder 22. The snap fit mechanism 28 engages the claw 31 with the step 29 to restrict the axial displacement of the female cylinder 15 with respect to the female cylinder 22 in the second direction DR2 opposite to the first direction DR1.

  As shown in FIG. 2, the fuel filter 11 includes a filter unit 33. The filter unit 33 is received at least partially from the open end in the space (first space) 34 inside the male cylindrical body 15. The first connection pipe 16 defines a flow passage 35 extending from the first space 34. When the male side cylindrical body 15 is fitted into the female side cylindrical body 22, the male side cylindrical body 15 and the filter unit 33 are received in the space (second space) 36 inside the female side cylindrical body 22 from the open end. The second connection pipe 23 defines a flow passage 37 extending from the second space 36. In this way, the accommodation space for the filter unit 33 is partitioned by the first space 34 and the second space 36 that at least partially overlap. Here, the accommodation space for the filter unit 33 is formed by the first space 34 and the second space 36 continuous to the first space 34.

  The filter unit 33 includes a cylindrical filter element 39 that partitions a linear passage 38 along the central axis Xis. The filter element 39 can be made of, for example, a nonwoven fabric that is alternately folded along a mountain fold line and a valley fold line that are parallel to the central axis Xis. The filter element 39 is sandwiched between the first end plate 41a and the second end plate 41b in the axial direction. The first end plate 41a and the second end plate 41b have a coaxial disk shape orthogonal to the central axis line Xis. A spacer (not shown) that maintains the distance between the first end plate 41a and the second end plate 41b may be sandwiched between the first end plate 41a and the second end plate 41b. The contact area between the first and second end plates 41a, 41b and the filter element 39 is hardened with an adhesive to form an adhesive layer 42.

  The second end plate 41b is fitted into the male cylindrical body 15 at the closed end. In the first space 34 of the male cylinder 15, a fuel reservoir 43 is formed between the outer periphery of the filter element 39 and the inner surface of the male cylinder 15. An annular seal 44 is sandwiched between the second end plate 41 b and the inner surface of the male cylindrical body 15. The annular seal 44 is formed of a flexible material such as rubber. The second end plate 41b partitions the first space 34 into a space on the filter element 39 side and a space on the first connecting pipe 16 side.

  The second end plate 41b has a circulation port 45 in the center. The circulation port 45 connects the passage 38 of the filter element 39 and the flow passage 35 in the first connection pipe 16. The fuel introduced from the flow path 37 of the second connection pipe 23 bypasses the first end plate 41 a and flows into the fuel reservoir 43. The fuel passes through the filter element 39 from the fuel reservoir 43, is filtered, flows into the passage 38, and flows into the flow passage 35 of the first connecting pipe 16 from the passage 38.

  The fuel filter 11 includes an annular seal 46 sandwiched between the outer peripheral surface of the male side cylindrical body 15 and the inner peripheral surface of the female side cylindrical body 22. The annular seal 46 is made of a flexible material such as rubber. The annular seal 46 is in liquid-tight contact with the outer peripheral surface of the male cylindrical body 15 and the inner peripheral surface of the female cylindrical body 22. Thus, liquid tightness is ensured at the boundary between the male side cylindrical body 15 and the female side cylindrical body 22.

  The inner peripheral surface of the female cylindrical body 22 is larger in diameter than the first inward cylindrical surface 47 that receives the annular seal 46 and the first inward cylindrical surface 47 and is continuous with the inner surface of the engagement piece 27. 2 inward cylindrical surfaces 48. A tapered surface 49 is formed between the first inward cylindrical surface 47 and the second inward cylindrical surface 48. The tapered surface 49 connects the second inward cylindrical surface 48 to the first inward cylindrical surface 47 and gradually expands in the radial direction from the first inward cylindrical surface 47 toward the second inward cylindrical surface 48.

  An abutting surface 51 is formed at the open end of the male side cylinder 15. The abutting surface 51 is abutted against the second housing half 14 in a plane orthogonal to the central axis Xis. Thus, the abutting surface 51 restricts the axial displacement of the male side cylinder 15 in the first direction DR1. When the abutment surface 51 is abutted against the second housing half 14, the claw 31 of the male side cylinder 15 is engaged with the step 29 of the engagement piece 27. The higher the dimensional accuracy of these positional relationships, the more the second housing half 14 can be prevented from rattling with respect to the first housing half 13.

  A first outward cylindrical surface 52 that receives the annular seal 46 is formed on the outer peripheral surface of the male side cylinder 15. The first outward cylindrical surface 52 is opposed to the first inward cylindrical surface 47 at a predetermined interval when the abutting surface 51 is abutted against the second housing half 14. The annular seal 46 is sandwiched between the first outward cylindrical surface 52 and the first inward cylindrical surface 47. When the male side cylinder 15 is fitted into the female side cylinder 22, an annular seal 46 is attached to the first outward cylindrical surface 52 in advance.

  A first radial surface 53 that extends radially outward on a plane orthogonal to the central axis Xis is connected to the end of the first outward cylindrical surface 52 far from the open end. The outer diameter of the first radial surface 53 is smaller than the inner diameter of the first inward cylindrical surface 47. A second outward cylindrical surface 54 is connected to the outer periphery of the first radial surface 53. The second outward cylindrical surface 54 is inserted into the first inward cylindrical surface 47. When the male cylindrical surface 15 is fitted into the female cylindrical surface 22, the first radial surface 53 receives the annular seal 46 and restricts the axial displacement of the annular seal 46.

  A second radial surface 55 is connected to the first inward cylindrical surface 47 at the end opposite to the tapered surface 49. The second radial surface 55 is a plane orthogonal to the central axis Xis and extends radially inward from the first inward surface 47. The minimum diameter of the second radial surface 55 is larger than the outer diameter of the first outward cylindrical surface 52. The first outward cylindrical surface 52 is inserted inside the second radial surface 55. The second radial surface 55 is opposed to the first radial surface 53 at an interval larger than the axial dimension of the annular seal 46 when the abutting surface 51 is abutted against the second housing half 14.

  The claw 31 has a vertical surface 56 that faces the step 29 when entering the window hole 32 and an inclination that gradually rises in the radial direction from the outer peripheral surface of the male cylinder 15 as it moves away from the open end of the male cylinder 15. Surface 57. The vertical surface 56 extends in a plane orthogonal to the central axis Xis. As a result of the vertical surface 58 of the step 29 and the vertical surface 56 of the claw 31 engaging with each other, the displacement of the male cylindrical body 15 in the second direction DR2 with respect to the female cylindrical body 22 is reliably prevented.

  Corresponding to the inclined surface 57 of the claw 31, a tapered surface 59 is formed at the free end of the engaging piece 27 so as to gradually expand in the radial direction from the inner peripheral surface. When the male cylindrical body 15 is fitted into the female cylindrical body 22, the tapered surface 59 can easily ride on the inclined surface 57 of the claw 31. Thus, the force for fitting the male side cylinder 15 into the female side cylinder 22 is converted into a force that is engaged in the radial direction and elastically deforms the piece 27.

  In joining the first housing half 13 and the second housing half 14, the male cylindrical body 15 is fitted into the female cylindrical body 22, and at least partially overlaps the first space 34 and the second space 36 of the filter unit 33. A storage space is defined. The snap fit mechanism 28 prevents the male cylindrical body 15 from coming off from the female cylindrical body 22. Therefore, the connection between the first housing half 13 and the second housing half 14 is maintained. Since the engagement of the claw 31 and the step 29 is released according to the elastic deformation of the engagement piece 27, the first housing half 13 and the second housing half 14 can be separated without breaking. . Thus, the filter unit 33 can be taken out and cleaned, or can be replaced with a new filter unit. Moreover, the claw 31 only needs to be engaged with the step 29 of the engaging piece 27, and does not need to protrude radially outward from the engaging piece 27. Therefore, the radial dimension of the fuel filter 11 can be suppressed. Since the engaging piece 27 and the snap-fit mechanism 28 are integrated into the first housing half 13 or the second housing half 14, the number of parts is minimized, assembly efficiency is increased, and parts may be lost. Is significantly reduced, and reliable work can be realized even in a poor environment.

  In the fuel filter 11, an annular seal 46 is sandwiched between the outer peripheral surface of the male side cylindrical body 15 and the inner peripheral surface of the female side cylindrical body 22. A seal is reliably ensured between the male side cylindrical body 15 and the female side cylindrical body 22. Fuel leakage can be reliably prevented.

  When the male cylinder 15 is fitted into the female cylinder 22 when the first housing half 13 and the second housing half 14 are joined, the inner surface of the engagement piece 27 and the second inward cylindrical surface 48 are annular. Pass through seal 46. Thereafter, the pressing force of the annular seal 46 gradually increases from the tapered surface 49 toward the first inward cylindrical surface 47. Therefore, excessive force does not act on the annular seal 46, and damage to the annular seal 46 can be avoided.

  When the nail | claw 31 engages with the level | step difference 29 by the snap fit mechanism 28, the displacement of the male side cylindrical body 15 is controlled by the butting of the butting surface 51 in the first direction DR1. At this time, the annular seal 46 is sandwiched between the first inward cylindrical surface 47 and the outward cylindrical surface 52. If the annular seal 46 is mounted on the outer periphery of the male cylindrical body 15 in advance, the annular seal 46 is received on the first radial surface 53 in the axial direction during the relative movement of the male cylindrical body 15. Since the second radial surface 55 faces the first radial surface 53 at an interval larger than the axial dimension of the annular seal 46, crushing of the annular seal 46 is avoided. The pressing surface 51 appropriately holds the clearance necessary for the snap fit mechanism 28 and contributes to suppression of unnecessary rattling.

  FIG. 3 schematically shows the overall configuration of the fuel pump module 71 according to the second embodiment. The fuel pump module 71 includes a module main body 72 and a fuel filter 73. A fuel pump 74 is incorporated in the module main body 72. A suction passage 76, a discharge passage 77 and a return passage 78 are defined in the pump housing 75 of the fuel pump 74. The pump housing 75 is formed in a cylindrical shape having a central axis Xis, and the suction passage 76 opens in the end surface 75a at one end in the axial direction. A fuel pipe 19 connected to the fuel injection valve 18 of the internal combustion engine 17 is connected to the discharge passage 77. A return pipe 79 connected to the fuel tank 24 is connected to the return passage 78.

  The fuel pump 74 includes an impeller chamber 81 connected to the suction passage 76. An impeller 82 is disposed in the impeller chamber 81. The impeller 82 is coupled to a rotation shaft 83 that is rotatably supported about the central axis Xis. An electric motor 84 is connected to the impeller 82. The electric motor 84 includes a rotor 84a coupled to the rotation shaft 83, and a stator 84b supported by the pump housing 75 while surrounding the rotor 84a. When a drive current is supplied to the coil of the stator 84b, the electric motor 84 operates and rotationally drives the impeller 82 around the central axis Xis.

  The module main body 72 includes a check valve 85. The check valve 85 is incorporated in the discharge passage 77. When the pressure in the discharge passage 77 is larger than the discharge pressure of the fuel pump 74, the valve body 85a of the check valve 85 is seated. This prevents back flow of fuel. When the discharge pressure of the fuel pump 74 exceeds the pressure in the discharge passage 77, the fuel flows from the fuel pump 74 into the discharge passage 77.

  The module main body 72 includes a pressure regulating valve 86. The pressure regulating valve 86 is incorporated in a return passage 78 branched from the discharge passage 77 downstream of the check valve 85. In the pressure regulating valve 86, when the pressure in the discharge passage 77 exceeds a predetermined value, the valve body 86a moves away from the valve seat 86b. At this time, the fuel in the discharge passage 77 is returned from the return passage 78 to the fuel tank 24.

  The module main body 72 includes a coupler 87. In the socket 87a of the coupler 87, a connection terminal 87b connected to a conducting wire 88 connected to the electric motor 74 is disposed. Coupler 87 is coupled to a male coupler (not shown). A drive current is supplied from the connection terminal 87 b toward the electric motor 74. Fuel is supplied from the discharge passage 77 toward the fuel injection valve 18 in accordance with the operation of the electric motor 74.

  The fuel filter 73 includes a filter housing 89 that is coupled to the pump housing 75 of the fuel pump 74. The filter housing 89 has a female cylindrical body 91 and a connecting pipe 92. A connecting tube 92 is formed at the closed end of the female cylindrical body 91. A fuel pipe 25 connected to the fuel tank 24 is connected to the connection pipe 92. The female-side cylindrical body 91 receives the fuel pump 74 in the first direction DR1 from the open end, and defines a space 93 that houses the filter unit 33 between the end surface 75a of the fuel pump 74. The suction passage 76 of the fuel pump 74 opens into a space 93 inside the female cylinder 91. The connection pipe 92 defines a flow passage 94 extending from the space 93 in the female side cylindrical body 91. The flow passage 94 is connected to the fuel pipe 25.

  The filter unit 33 is configured in the same manner as the filter unit 33 described above. In the filter unit 33, the filter element 39 is held between the first end plate 41a and the second end plate 41b. The second end plate 41b is fitted inside the female cylindrical body 91 and partitions the space 93 in the female cylindrical body 91 into a space on the filter element 39 side and a space on the suction passage 76 side. At this time, an annular seal 95 is sandwiched between the second end plate 41 b and the inner surface of the female cylindrical body 91. The fuel introduced from the flow passage 94 of the connecting pipe 92 flows into the fuel reservoir 43 while bypassing the first end plate 41a. The fuel passes from the fuel reservoir 43 through the filter element 39, is filtered, flows into the passage 38, and flows into the suction passage 76 of the fuel pump 74 from the passage 38.

  A snap fit mechanism 96 is constructed between the filter housing 89 and the pump housing 75. In the construction of the snap fit mechanism 96, the engaging piece 27 is formed at the open end of the female side cylindrical body 91 as described above. The snap fit mechanism 96 engages the step 29 defined by the engagement piece 27 with the claw 31 defined on the outer periphery of the pump housing 75, and the female cylinder in the second direction DR2 opposite to the first direction DR1. The axial displacement of the pump housing 75 is restricted with respect to the body 91.

  The fuel pump module 71 includes an annular seal 97 sandwiched between the outer peripheral surface of the pump housing 75 and the inner peripheral surface of the female side cylindrical body 91. The annular seal 97 is formed of a flexible material such as rubber. The annular seal 97 is in liquid-tight contact with the outer peripheral surface of the pump housing 75 and the inner peripheral surface of the female cylindrical body 91. Thus, liquid tightness is ensured at the boundary between the pump housing 75 and the female cylindrical body 91.

  The inner peripheral surface of the female cylindrical body 91 has a first inward cylindrical surface 98 that receives the annular seal 97 and a larger diameter than the first inward cylindrical surface 98 and is continuous with the inner surface of the engaging piece 27. 2 inward cylindrical surfaces 99. A tapered surface 101 is formed between the first inward cylindrical surface 98 and the second inward cylindrical surface 99. The tapered surface 101 connects the second inward cylindrical surface 99 to the first inward cylindrical surface 98 and gradually expands in the radial direction from the first inward cylindrical surface 98 toward the second inward cylindrical surface 99.

  An end surface 75a of the pump housing 75 is abutted against the second end plate 41b of the filter unit 33 on a plane orthogonal to the central axis Xis. The first end plate 41 a of the filter unit 33 is abutted against the closed end of the female cylindrical body 91. Thus, the axial displacement of the pump housing 75 is restricted in the first direction DR1. When the end surface 75 a of the pump housing 75 is abutted against the second end plate 41 b of the filter unit 33, the claw 31 of the pump housing 75 is engaged with the step 29 of the engagement piece 27. The higher the dimensional accuracy of these positional relations, the more the filter housing 89 can be prevented from rattling with respect to the module body 72.

  On the outer peripheral surface of the pump housing 75, an outward cylindrical surface 102 that is inserted into the first inward cylindrical surface 98 of the female side cylindrical body 91 is formed. A groove 103 for receiving the annular seal 97 is defined in the outward cylindrical surface 102. The groove 103 is opposed to the first inward cylindrical surface 98 when the pump housing 75 is abutted against the second end plate 41 b of the filter unit 33. The annular seal 97 is sandwiched between the outward cylindrical surface 102 and the first inward cylindrical surface 98 while being accommodated in the groove 103. When the pump housing 75 is fitted into the female cylinder 91, an annular seal 97 is attached to the outward cylindrical surface 102 in advance.

  When the filter housing 89 is attached to the module main body 72 including the fuel pump 74, the pump housing 75 is fitted into the female side cylindrical body 91. The pump housing 75 defines an accommodation space for the filter unit 33 between the end surface 75a. The snap fit mechanism 96 prevents the module main body 72 from coming off from the female cylindrical body 91. Therefore, the coupling between the fuel filter 73 and the module main body 72 is maintained. Since the engagement of the claw 31 and the step 29 is released according to the elastic deformation of the engagement piece 27, the pump housing 75 and the filter housing 89 can be separated without being broken. Thus, the filter unit 33 can be taken out and cleaned, or can be replaced with a new filter unit. Moreover, the claw 31 only needs to be engaged with the step 29 of the engaging piece 27, and does not need to protrude radially outward from the engaging piece 27. Therefore, the radial dimension of the pump housing 75 can be suppressed. Since the engaging piece 27 and the snap-fit mechanism 96 are integrated into the pump housing 75 or the filter housing 89, the number of parts is minimized, the assembly efficiency is increased, and the possibility of missing parts is remarkably reduced. Certain work can be realized even in a difficult environment.

  DESCRIPTION OF SYMBOLS 11 ... Fuel filter, 13 ... 1st housing half body, 14 ... 2nd housing half body, 15 ... Male side cylindrical body, 16 ... 1st connecting pipe, 22 ... Female side cylindrical body, 23 ... 2nd connecting pipe, 27 ... engaging piece, 28 ... snap fit mechanism, 29 ... step, 31 ... claw, 33 ... filter unit, 34 ... first space, 35 ... flow path, 36 ... second space, 37 ... flow path, 46 ... annular seal , 47 ... first inward cylindrical surface, 48 ... second inward cylindrical surface, 49 ... tapered surface, 51 ... abutting surface, 52 ... outward cylindrical surface (first outward cylindrical surface), 53 ... first diameter Directional surface, 55 ... second radial surface, 71 ... fuel pump module, 74 ... fuel pump, 75a ... end surface, 89 ... housing (filter housing), 91 ... female side cylindrical body, 92 ... connecting pipe, 93 ... space, 94 ... flow passage, 96 ... snap-fi DOO mechanism, DR1 ... first direction, DR2 ... second direction, Xis ... central axis.

Claims (5)

A filter unit (33);
A male cylinder (15) defining a first space (34) for receiving the filter unit (33) at least partially from an open end, and a flow passage (35) extending from the first space (34) are defined. A first housing half (13) having a first connecting pipe (16) at the closed end;
A female cylinder (22) defining a second space (36) for receiving the male cylinder (15) in the first direction (DR1) from the open end, and a flow passage extending from the second space (36) A second housing half (14) having a second connecting pipe (23) defining (37) at the closed end;
An elastically deformable engagement piece (27) extending in the direction of the generatrix along the outer periphery of the male cylinder (15) from the female cylinder (22),
The claw (31) defined on the outer periphery is engaged with the step (29) defined on the engagement piece (27) in the second direction (DR2) opposite to the first direction (DR1). A fuel filter comprising: a snap fit mechanism (28) for restricting axial displacement of the male cylindrical body (15) with respect to the female cylindrical body (22).   The fuel filter according to claim 1, further comprising an annular seal (46) sandwiched between an outer peripheral surface of the male cylindrical body (15) and an inner peripheral surface of the female cylindrical body (22). And fuel filter. The fuel filter according to claim 2, wherein the inner peripheral surface of the female cylindrical body (22) is
A first inward cylindrical surface (47) for receiving the annular seal (46);
A second inward cylindrical surface (48) having a larger diameter than the first inward cylindrical surface (47) and continuing to the inner surface of the engaging piece (27);
The second inward cylindrical surface (48) is connected to the first inward cylindrical surface (47), and gradually from the first inward cylindrical surface (47) toward the second inward cylindrical surface (48). A fuel filter comprising a tapered surface (49) extending to the surface. The fuel filter according to claim 3, wherein
Formed at the open end of the male side cylinder (15) and abutted against the second housing half (14) in a plane orthogonal to the central axis (Xis), the male side in the first direction (DR1). An abutment surface (51) for regulating the axial displacement of the side cylindrical body (15);
The first inward cylindrical surface (47) formed on the outer peripheral surface of the male cylindrical body (15) and when the abutting surface (51) is abutted against the second housing half (14). An outwardly facing cylindrical surface (52) which is faced to receive the annular seal (46);
A first radial surface (53) connected to an end of the outward cylindrical surface (52) far from the open end and extending radially outward in a plane perpendicular to the central axis (Xis);
From the axial dimension of the annular seal (46) when connected to the first inward cylindrical surface (47) and the abutting surface (51) is abutted against the second housing half (14). And a second radial surface (55) that faces the first radial surface (53) at a large interval. A female cylindrical body that receives the fuel pump (74) in the first direction (DR1) from the open end and divides a space (93) for accommodating the filter unit (33) between the end surface (75a) of the fuel pump (74). (91) and a housing (89) having a connecting pipe (92) defining a flow passage (94) extending from the space (93) at the closed end;
An elastically deformable engagement piece (27) extending from the housing (89) along the outer periphery of the fuel pump (74) in the direction of the bus,
The claw (31) defined on the outer periphery is engaged with the step (29) defined on the engagement piece (27) in the second direction (DR2) opposite to the first direction (DR1). A fuel pump module comprising: a snap fit mechanism (96) for restricting axial displacement of the fuel pump (74) with respect to the female cylindrical body (91).

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