JP2023158321A - fuel supply device - Google Patents

Abstract

To reduce the number of part items and assembling man-hours by an integration effect of an annular collar and an upper case, and to suppress the come-off of irregularity engagement parts of the upper and lower cases from each other, in a fuel supply device in which a seal ring is interposed between opposing peripheral faces of an outer cylinder part erected on a tank bottom wall and surrounding a tank opening, and an inner cylinder part surrounded by the outer cylinder part at an entire periphery being a part of an erecting wall extending to the inside of a tank from a bottom wall part of the lower case, and the seal ring is gripped between the annular collar which is fit to an external peripheral face of the erecting wall and an upward step part arranged at the external peripheral face of the erecting wall at a lower part of the annular collar.SOLUTION: In a fuel supply device in which a seal ring 41 is gripped between an annular collar 27 fit to an external periphery of an erecting wall Wo, and an upward step part 28 arranged at an external periphery of the erecting wall Wo at a lower part of the annular collar 27, the annular collar 27 is integrally formed at an upper case 20.SELECTED DRAWING: Figure 2

Description

The present invention provides a fuel supply device, in particular, a mounting portion fixed to a tank bottom wall of a fuel tank, a case bottom wall portion that closes an opening in the tank bottom wall, and a case bottom wall portion extending inward from the case bottom wall portion. a lower case having an upright wall; and an upper case having an engaging piece formed along the inside of the upright wall to sandwich a vertically placed fuel pump between the lower case and the upright wall and the upper case; The present invention relates to a fuel supply device in which upper and lower cases are connected by mutually engaging an engagement recess provided on one of the engagement pieces and an engagement protrusion provided on the other of the engagement pieces.

In the above fuel supply device, there is an outer cylindrical portion that stands upwardly on the tank bottom wall so as to surround the entire circumference of the opening in the tank bottom wall, and an outer cylindrical portion that is part of the upright wall and surrounds the entire periphery of the outer cylindrical portion. A device in which a seal ring is interposed between the circumferential surface facing the inner cylindrical portion to seal the gap is conventionally known, as described in Patent Document 1, for example.

JP 2017-160829 Publication

By the way, in the fuel supply device of Patent Document 1, the seal ring includes an upper annular collar that is fitted and fixed to the outer periphery of the upright wall of the lower case, and an upwardly directed step part (specifically It is held between the lower annular collar (which fits around the outer periphery of the upright wall). That is, the seal ring is held in the annular groove formed between the upper annular collar and the upward step below the upper annular collar on the outer periphery of the upstanding wall.

If the annular groove is formed using the upper annular collar, which is a separate part from the lower case, as in this conventional structure, the disadvantages of directly molding the annular groove on the outer periphery of the upstanding wall, i.e., the position corresponding to the upper annular collar, can be avoided. It is possible to avoid the inconvenience that a thick portion is formed on the outer periphery of the upright wall, resulting in molding defects (for example, sink marks, voids, etc.).

On the other hand, since the upper annular collar is a separate part from the lower case, there is a problem in that the number of parts and the number of assembly steps increase, resulting in an increase in cost.

The present invention has been proposed in view of the above, and an object of the present invention is to provide a fuel supply device that can solve the above problems of conventional devices with a simple structure.

In order to achieve the above object, the present invention provides a mounting part fixed to the tank bottom wall of a fuel tank, a case bottom wall part that closes an opening in the tank bottom wall, and an inner part of the fuel tank from the case bottom wall part. a lower case having an upright wall extending to the side; an upper case having an engagement piece formed along the inside of the upright wall to sandwich a vertically placed fuel pump between the lower case and the upright wall; The upper and lower cases are connected by engaging an engagement recess provided on one of the upright wall and the engagement piece with an engagement protrusion provided on the other. an outer cylindrical part that stands upwardly on the bottom wall of the tank so as to surround the entire circumference of the opening, and an inner cylindrical part that is part of the upright wall and is surrounded all the way around the outer cylindrical part. A seal ring is interposed between the opposing circumferential surfaces of the upright wall, and the seal ring includes an annular collar fitted to the outer circumferential surface of the upright wall, and a seal ring below the annular collar of the upright wall. A first feature of the fuel supply device that is sandwiched between the fuel supply device and the upwardly facing stepped portion provided on the outer periphery is that the annular collar is integrally formed with the upper case.

Further, in addition to the first feature, the present invention has a second feature that the upper end of the annular collar is located above the lower end of the engagement piece when the upper and lower cases are combined. do.

In addition to the first feature, the present invention provides that the lower case has an inner side that is located radially inward from the upright wall and extends from the case bottom wall toward the inside of the fuel tank. The fuel pump is fitted into the inner wall, and the upper case fits and holds the upper outer periphery of the fuel pump through the inner wall when the upper and lower cases are connected. A third feature is that the annular collar has a body, and the upper part of the annular collar is integrally connected to the body through a plurality of support arms.

In the present invention, a "vertical fuel pump" refers to a fuel pump whose vertical axis extends in the vertical direction, and includes, for example, a fuel pump whose vertical axis is inclined from the vertical line due to the inclination of the bottom wall of the tank.

According to the first feature of the present invention, the outer cylindrical part is erected on the tank bottom wall and surrounds the entire circumference of the tank opening, and the upright wall extends inward from the bottom wall of the lower case. A seal ring is interposed between the opposing peripheral surface of the inner cylindrical part that is a part of the outer cylindrical part and is surrounded by the entire circumference of the outer cylindrical part, and the seal ring seals the space between the inner cylindrical part and the outer cylindrical part. In a fuel supply device that is sandwiched between an annular collar to be fitted and an upward step provided on the outer periphery of a standing wall below the annular collar, the annular collar is integrally formed with the upper case. The effect of integrating the annular collar and the upper case not only reduces the number of parts, but also allows the annular collar attached to the upper case to be attached to a predetermined location on the outer periphery of the upright wall at the same time as the upper and lower cases are connected to each other. Since it can be automatically placed and fixed, the number of assembly steps can be reduced, which can greatly contribute to cost savings. In addition, the upright wall has an engagement piece for the upper case on its inner circumference, and an annular collar integrated with the upper case on its outer circumference, near the concave and convex engagement parts between the upper and lower cases. Since the relative displacement in the radial direction can be suppressed, the disengagement of the concave-convex engaging portion due to the relative displacement in the radial direction can be effectively suppressed.

According to the second feature, the upper end of the annular collar is located above the lower end of the engaging piece when the upper and lower cases are connected, so that the radial outward displacement of the upright wall is prevented. The vicinity of the engagement piece is effectively suppressed by the annular collar integral with the upper case, and therefore, the detachment of the concave-convex engagement portion is more effectively suppressed.

According to the third feature, the lower case has an inner wall located radially inward from the upright wall and extending from the bottom wall of the case toward the inner side of the fuel tank. The fuel pump is fitted to the inner wall, and the upper case has a body that fits and holds the upper outer periphery of the fuel pump through the inner wall when the upper and lower cases are connected. The upper part of the annular collar is coupled together via a plurality of support arms. As a result, the upper part of the fuel pump is fitted and held not only by the inner wall of the lower case but also by the body of the upper case via the inner wall, which not only increases the rigidity of the case as a whole, but also increases the rigidity of the case as a whole. The bonding strength between the upper and lower cases is also increased. Moreover, by minimizing the radial distance between the annular collar and the relatively large-diameter and highly rigid body of the upper case, it is possible to effectively increase the support rigidity of the annular collar by the body.

An overall perspective view showing how a fuel supply device according to an embodiment of the present invention is attached to a fuel tank, with a part of the tank cut away. A vertical cross-sectional view of the essential parts of the fuel supply device taken through the snap-fit mechanism between the upper and lower cases (cross-sectional view taken along line 2X-2X in FIGS. 1 and 5). A longitudinal cross-sectional view of the fuel supply device taken along a cross section passing through the upper and lower case side fuel pipes and the pressure regulator (a cross-sectional view taken along the line 3X-3X in FIGS. 1 and 5). An exploded perspective view of the fuel supply device viewed from approximately the same direction as FIG. 1. An exploded view of the case showing a comparison between the bottom view of the upper case and the top view of the lower case. Perspective view of the upper case seen from the opposite direction from Figure 1.

Embodiments of the present invention will be described below with reference to the accompanying drawings.

First, in FIGS. 1 to 6, the tank bottom wall Tb of a fuel tank T mounted on a vehicle, for example, a motorcycle, is used to suck and pressurize the fuel in the fuel tank T so as to connect it to an on-vehicle engine (not shown). A fuel pump module FM for supplying fuel to a fuel injection valve (fuel injection valve) is attached so as to liquid-tightly close an opening Tbo provided in the tank bottom wall Tb. An outer cylindrical portion Tbc that cylindrically stands upward from the tank bottom wall Tb over the entire circumference is integrally formed at the opening edge of the opening Tbo.

This fuel pump module FM includes a lower case 10 that is removably connected to the tank bottom wall Tb and extends inside and outside the fuel tank T, and a lower case 10 that is located inside the fuel tank T and is removably connected to the lower case 10. an electric pump unit P which is sandwiched and fixed between the upper and lower cases 20 and 10; The main components include a filter 8 that communicates with the inside of the fuel tank T, and a pressure regulator R that is attached to the upper case 20 and regulates the discharge oil pressure of the pump unit P to a predetermined upper limit value or less.

The upper and lower cases 20, 10 are each integrally molded from a synthetic resin material. Thus, the fuel pump module FM is an example of the fuel supply device of the present invention, and the pump unit P is an example of the fuel pump of the present invention.

In this specification, the term "radial direction" refers to the radial direction of a virtual arc centered on the vertical axis of the pump unit P as a fuel pump, and the term "circumferential direction" refers to the circumferential direction of the virtual arc. The term "axial direction" refers to the direction along the longitudinal axis.

The pressure regulator R is normally kept in a closed state, and when the discharge oil pressure of the pump unit P exceeds a set value, the pressure regulator R is configured to open the valve at that pressure and recirculate a portion of the discharged oil into the fuel tank T. , its function is similar to that of a conventionally well-known pressure regulator.

The pump unit P includes a cylindrical unit case Pc arranged vertically, a pump part (not shown) built into the unit case Pc, and a motor part (not shown) which is also built in the unit case Pc and drives the pump part. Equipped with. The unit case Pc has a fuel inlet Pci at its lower end and a fuel outlet Pco at its upper end.

The lower case 10 is integrally connected on the same axis to a bottomed cylindrical case bottom wall part 12 that closes the opening Tbo of the tank bottom wall Tb, and an upper end part of the cylindrical part 12c of the case bottom wall part 12. An outer wall Wo extending inward (i.e., upward) of the fuel tank T and an outer wall Wo extending inward (i.e., upward) of the fuel tank T are integrally connected to the upper surface of the bottom portion 12b of the case bottom wall portion 12. a lower case-side fuel pipe 10p integrally connected to the bottom 12b and cylindrical portion 12c of the case bottom wall 12 and extending vertically in a straight pipe shape; and a cylindrical portion 12c of the case bottom wall 12. It has an outward flange-shaped attachment part 11 that is integrally connected to the outer peripheral part of the fuel tank T and extends radially outward outside the fuel tank T. The outer wall Wo is an example of the standing wall of the present invention.

The inner wall Wi has a substantially arcuate cross section and is located at a position separated (that is, spaced apart) from the outer wall Wo in the radial direction, and a unit case is provided on the upper inner peripheral surface of the inner wall Wi. The outer peripheral portion of Pc is fitted and held. That is, the upper inner circumferential surface of the inner wall Wi functions as a displacement regulating portion that regulates the radial displacement of the unit case Pc. Furthermore, a plurality of insertion pieces Wit, which are part of a second engagement mechanism J2 to be described later, are integrally provided at the upper end of the inner wall Wi at intervals in the circumferential direction.

Further, as is clear from FIG. 5, the lower case side fuel pipe 10p is located radially inward from the outer circumferential surface of the outer wall Wo and is arranged so as to partially overlap the inner wall Wi in the radial direction in plan view. The lower case side fuel pipe 10p and the inner wall Wi are integrally connected to each other at the overlapping portion.

On the other hand, as is clear from FIGS. 4 and 5, the outer wall Wo includes a short cylindrical outer wall base 13M continuously formed at the upper end of the cylindrical portion 12c of the case bottom wall 12, and an upper end of the outer wall base 13M. It is provided with a plurality of outer wall tips 13A to 13D that protrude at intervals in the circumferential direction. The outer wall tip portions 13A to 13D are each formed to have a sub-arc shape in cross section, and the upper end portion of each has a rectangular through hole that constitutes an engagement recess Woa of a snap fit mechanism J1 to be described later.

In particular, the outer wall base 13M constitutes the inner cylindrical portion of the present invention, and is concentrically surrounded by the aforementioned outer cylindrical portion Tbc of the tank bottom wall Tb. A seal ring 41 is interposed between the opposing circumferential surfaces of the outer wall base 13M and the outer cylindrical portion Tbc to provide a liquid-tight seal therebetween. This seal ring 41 is arranged axially, that is, in the vertical direction, between an upper annular collar 27 and a lower annular collar 28 that are fitted onto the outer peripheral surface of the outer wall Wo (particularly the outer wall base 13M functioning as an inner cylindrical portion). It is held in such a way that relative displacement is impossible.

The upper annular collar 27 is an example of an annular collar of the present invention, and is formed integrally with the upper case 20 as described later. The lower annular collar 28 is a functional component for forming an upward annular step at the lower part of the outer periphery of the outer wall base 13M, and the lower end of the lower annular collar 28 extends downward through the tank opening Tbo. It is supported in contact with the upper surface of the mounting portion 11 of the lower case 10. In addition, in the outer peripheral part of the outer wall base 13M of the embodiment, the root part connected to the attachment part 11 is formed to have a large diameter for reinforcement, and accordingly, the inner peripheral surface of the lower annular collar 28 is formed into a stepped cylindrical surface. be done.

Incidentally, the mounting portion 11 is arranged such that its upper surface faces the lower surface of the tank bottom wall Tb via a gap, and is fastened to the tank bottom wall Tb by a plurality of bolts 14 distributed so as to surround the opening Tbo. That is, the base end 14b of each bolt 14 is fixed (for example, welded) to the tank bottom wall Tb, and the threaded shaft portion 14a extends downward and passes through the washer 15 and the mounting portion 11. A nut 16 that engages with the lower surface of the mounting portion 11 is screwed into the portion 14a. Therefore, by tightening the nut 16, the mounting portion 11, and thus the lower case 10, are fastened to the tank bottom wall Tb.

Furthermore, on the radially inward side of the array group of bolts 14, the opposing surfaces between the mounting portion 11 and the tank bottom wall Tb are sealed with an annular dust seal 42 that surrounds the entire circumference of the opening Tbo. This dust seal 42 is positioned in the radial direction by fitting into the outer circumferential portion of an annular positioning projection 11t protruding from the upper surface of the mounting portion 11 so as to surround the opening Tbo.

Further, the bottom wall portion 12 of the case accommodates a lower portion of the filter 8 and a suction pipe 17 that communicates the inside of the filter 8 with the suction port Pci of the pump unit P. The filter 8 has a conventionally well-known structure in the fuel pump module FM, and includes, for example, a flexible flat cloth bag and a filter medium housed in the cloth bag, and the upper part of the filter 8 has a cylindrical shape. The outer wall base 13M and the inner circumferential surface of the cylindrical portion 12c of the case bottom wall 12 are disposed over approximately half the circumference thereof and along the inner circumferential surface thereof.

One end opening of the suction pipe 17 is connected to the inside of the filter 8 via a connector, and the other end opening is connected to the suction port Pci. In addition, the suction pipe 17 of the embodiment has a vertical pipe portion 17v and a horizontal pipe portion 17h and is formed in a T-shape, and in particular, the lower end of the vertical pipe portion 17v is engaged with the bottom portion 12b of the case bottom wall portion 12. and the upper end engages with the lower end surface of the pump unit P. Thereby, the lower part of the pump unit P is supported at a predetermined position on the case bottom wall portion 12 via the suction pipe 17.

Furthermore, the exposed part of the case bottom wall part 12 to the outside of the fuel tank T is electrically connected to the fuel discharge pipe 7 for discharging the discharged fuel from the pump unit P to the outside, and to the motor part of the pump unit P. coupler portions (not shown) are integrally connected. The outer end (outlet end) of the fuel discharge pipe 7 is connected to a fuel pipe (not shown) that extends to the engine side, while the inner end (inlet end) thereof is connected to the lower case side within the case bottom wall 12. It communicates with the lower end of the fuel pipe 10p (see FIG. 3). Further, external wiring extending from an external current supply device (not shown) is removably connected to the coupler portion.

Although the case bottom wall portion 12 in the embodiment is formed in a cylindrical shape with a bottom, it may be formed in a disk shape that can close the tank bottom wall Tb.

Next, an example of the upper case 20 will be described with reference mainly to FIGS. 1, 3, 5, and 6. The cylindrical frame part 22c) is provided with a body part 23 having a substantially arcuate cross section and supporting the upper outer periphery of the pump unit P by being connected downwardly to the cylindrical frame part 22c) via a plurality of connecting walls 22w. The upper case 20 holds the pump unit P between its upper wall portion 22 and the lower case 10 (case bottom wall portion 12) so as not to be vertically movable.

As is clear from FIGS. 1 and 2, the upper end of the body portion 23 is at approximately the same height as the upper end of the inner wall Wi of the lower case 10 (that is, the insertion piece Wit). When the upper and lower cases 20 and 10 are connected, the lower inner periphery of the body 23 fits the upper outer periphery of the pump unit P via the upper part of the inner wall Wi, as shown in FIG. It is possible to hold it.

Incidentally, in the embodiment, the upper wall portion 22 of the upper case 20 is shown as being composed of a framework body in which a plurality of cylindrical frame portions 22c and vertical and horizontal straight frame portions 22a and 22b are connected and integrated. This may also be a non-framed (for example solid) wall structure.

Further, an upper case side fuel pipe 20p is integrally formed in the upper wall part 22 of the upper case 20 (i.e., the framework body), and this upper case side fuel pipe 20p also serves as a strength member of the upper wall part 22. be done. This upper case side fuel pipe 20p has a first opening 20pr at one end facing the pressure regulator R, and a second opening 20pp at the middle part facing the discharge port Pco as a discharge part of the pump unit P. Further, the third opening 20pf on the other end side is communicated (more specifically, fitted and connected in a liquid-tight manner) with the lower case side fuel pipe 10p on the lower case 10 side.

In particular, at the lower end of a portion of the peripheral wall of the third opening 20pf, as is clear from FIGS. are integrally vertically installed, and the lower case side fuel pipe 10p is inserted into the fuel pipe covering portion 23c. Moreover, when the upper and lower cases 20 and 10 are connected to each other, the fuel pipe covering portion 23c has an outer peripheral portion that faces the circumferential gap existing between the outer wall tip portions 13B and 13C of the outer wall Wo as an upright wall. I'm here.

Next, an example of the snap fit mechanism J1 as a first engagement mechanism that removably connects the lower case 10 and the upper case 20 will be described.

On the outer periphery of the body portion 23 of the upper case 20, a plurality of (four in the illustrated example) base portions 21b of the engaging pieces 21 are provided at intervals in the circumferential direction and protrude laterally (i.e., outward in the radial direction). An upward tip 21a is connected to the outer end of the base 21b. The tip 21a of each engagement piece 21 extends upward with a gap between it and the outer circumferential surface of the body 23, and within the gap, the tip 21a can control the engagement and disengagement operation of the snap fit mechanism J1. It is elastically deformable as permissible.

Further, on the outer surface of the intermediate portion of the tip portion 21a of the engagement piece 21, as is clear from FIG. 2, an engagement convex portion 21at protrudingly extends outward in the radial direction. The above-mentioned engagement recess Woa is provided on the outer wall Wo (particularly the upper part of the outer wall tips 13A to 13D) corresponding to the engagement projection 21at. It is possible to engage the concave and convex surfaces. The engagement protrusion 21at and the engagement recess Woa cooperate with each other to constitute a snap-fit mechanism J1.

Although not shown, contrary to the embodiment, an engaging convex portion is provided on the outer wall Wo (particularly the upper part of the outer wall tip portions 13A to 13D), and an engaging convex portion is provided on the upper case 20 (the tip portion 21a of the engaging piece 21). The snap fit mechanism J1 may be configured by providing an engaging concave portion in each of the engaging convex portions and the engaging concave portions.

When the upper case 20 is pushed down from above into the lower case 10 while aligning the engagement protrusion 21at and the engagement recess Woa, the engagement piece 21 is elastically deformed and The engaging convex portion 21at and the engaging concave portion Woa can be engaged with each other in a concave-convex manner. In this case, the engagement protrusion 21at of the embodiment has a lower surface formed as a downward guiding slope for smoothing the above-mentioned uneven engagement, and an upper surface that accurately engages the inner edge of the engagement recess Woa. The locking surface is formed into a substantially horizontal locking surface.

Moreover, the above-mentioned uneven engagement can be easily released by, for example, pushing the upper end portion 21ah of the tip portion 21a of the engaging piece 21 inward in the radial direction.

Further, in the upper part of the upper case 20, a plurality of through holes 20h, which are part of the second engagement mechanism J2, are provided at intervals in the circumferential direction and in the vertical direction (see FIGS. 1, 2, and 3). 5). In the embodiment, the through hole 20h is formed between the opposing circumferential surfaces of the upper inner periphery of the body portion 23 and the lower outer periphery of the cylindrical frame portion 22c of the upper wall portion 22 so as to have a sub-arc shape in cross section. The through hole 20h cooperates with the aforementioned insertion piece Wit protruding from the upper end of the inner wall Wi to be inserted into and engaged with the through hole 20h in a vertically removable manner to form a second engagement mechanism J2. .

By the way, between the inner periphery of the upper wall tips 13A to 13D and the outer periphery of the pump unit P, the filter 8 connected to the suction port Pi of the pump unit P is arranged as described above. As is clear from FIGS. 2 and 5, the engaging piece 21 on the upper case 20 side located directly above the filter 8 is located above the filter 8 when viewed in the axial direction of the pump unit P (in other words, when viewed from the plane) (visually) at a position overlapping at least a portion of the filter 8.

Next, a structure for supporting the upper annular collar 27 to the upper case 20 will be explained. The upper part of the upper annular collar 27 is integrally connected to and supported by the outer periphery of the body part 23 of the upper case 20 via a plurality of support arms 60 to 63 and 66 to 69 arranged at intervals in the circumferential direction. Further, the upper part of the upper annular collar 27 is also integrally connected and supported on the outer peripheral part of the fuel pipe covering part 23c which is integral with the body part 23 via a plurality of support arms 64 and 65.

Further, the upper annular collar 27 has notches 27o1 to 27o3 that open at the upper edge thereof and are spaced apart from each other in the circumferential direction. These notches 27o1 to 27o3 allow fuel in the fuel tank T to be smoothly guided to the filter 8 side, or to facilitate wiring work in the fuel pump module FM.

Next, the operation of the above embodiment will be explained. The fuel pump module FM is assembled in advance outside the fuel tank T before being set in the fuel tank T, and after the assembly is inserted into the fuel tank T from the upper case 20 side through the opening Tbo in the tank bottom wall Tb. Next, the lower case 10 is fixed to the tank bottom wall Tb so as to close the opening Tbo.

When assembling this fuel pump module FM, built-in components (ie, filter 8, suction pipe 17, pump unit P, etc.) are temporarily placed in predetermined positions of lower case 10, and necessary wiring work is performed. The above temporary placement work includes fitting the seal ring 41 and the lower annular collar 28 to the outer periphery of the outer wall base 13M (i.e., inner cylindrical part) of the lower case 10, and fitting the dust seal 42 to a predetermined position on the upper surface of the mounting part 11. This also includes the work of setting.

Thereafter, the upper and lower cases 20 and 10 are connected via the snap-fit mechanism J1, and by this connection, the pump unit P is fitted and held in the inner wall Wi of the lower case 10 in a vertical position. The seal ring 41 and the lower annular collar 28 which are sandwiched between the cases 20 and 10 and which are located on the outer periphery of the outer wall base 13M (that is, the inner cylindrical part) are prevented from moving in the axial direction by the upper annular collar 27 that is integrated with the upper case 20. and fixed in place.

By the way, in the joining work between the upper and lower cases 20 and 10, for example, while aligning the engagement protrusion 21at and the engagement recess Woa of the snap fit mechanism J1, the upper case 20 is pushed down from above with respect to the lower case 10. Make sure they fit together. With the fitting, the engagement protrusion 21at and the engagement recess Woa are brought into uneven engagement with each other while the engagement piece 21 is elastically deformed, thereby coupling the upper and lower cases 20 and 10 together. At the same time, the insertion piece Wit at the upper end of the inner wall Wi is inserted into the through hole 20h of the upper case 20, whereby the second engagement mechanism J2 is also brought into the engaged state.

In this way, in the fuel pump module FM of the embodiment, in addition to the snap fit mechanism J1 that engages the outer wall Wo of the lower case 10 and the upper case 20 in a concave-convex manner, the inner wall Wi of the lower case 10 and the upper case 20 are By specially providing the second engagement mechanism J2 for engagement, the mutual engagement parts of the upper and lower cases 20 and 10 can be separated at two different radial positions (i.e., the inner wall Wi and the outer wall Wo). Since the coupling force between the upper and lower cases 20 and 10 is increased as a whole, it is possible to effectively suppress the detachment of the concave-convex engaging portion of the snap-fit mechanism J1. Therefore, even if a strong impact is applied to the pump unit P, the upper case 20 is difficult to come off from the lower case 10.

Furthermore, the snap-fit mechanism J1 is arranged on the outside of the fuel pump module FM in the radial direction of the pump, where built-in parts are not concentrated, so that the snap-fit mechanism J1 engages when the engagement protrusion 21at and the engagement recess Woa engage with each other. A sufficient space for allowing the elastic deformation of the joint piece 21 can be secured, making it easy to engage and disengage the snap-fit mechanism J1. On the other hand, the second engagement mechanism J2 is composed of a vertical through hole 20h provided in the upper case 20 and an insertion piece Wi provided in the upper part of the inner wall Wi and insertable into the through hole 20h. When removing the upper case 20 from the case 10, the second engagement mechanism J2 can be easily disengaged by simply lifting the upper case 20, and the workability is extremely good.

By the way, the fuel pump module FM of the present embodiment includes an outer cylindrical portion Tbc that is erected on the tank bottom wall Tb and surrounds the entire circumference of the tank opening To, and an outer cylindrical portion Tbc that is located on the tank inner side from the case bottom wall portion 12 of the lower case 10. A seal ring 41 is interposed between the opposing circumferential surface of the outer wall base 13M (i.e., the inner cylindrical portion) extending to the upper annular collar, and the seal ring 41 is fitted onto the outer circumferential surface of the outer wall base 13M. 27 and a lower annular collar 28 (that is, an upward step) provided below the upper annular collar 27 on the outer periphery of the outer wall base 13M. The technical feature is that it is formed integrally with the case 20.

According to the effect of integrating the upper annular collar 27 and the upper case 20, the number of parts is reduced, and at the same time the upper and lower cases 10 and 20 are connected to each other, the upper annular collar 27 and the upper case 20 are connected to each other. The upper annular collar 27 can be automatically arranged and fixed at a predetermined location on the outer periphery of the outer wall base 13M, and the number of assembly steps can be reduced, which can greatly contribute to cost savings.

In addition, the outer wall base 13M has an engagement piece 21 for the upper case 20 on its inner circumference, and an upper annular collar 27 integral with the upper case 20 on its outer circumference. , 20 in the vicinity of the snap-fit mechanism J1 (i.e., the concave-convex engaging portion), it is possible to suppress the relative displacement in the radial direction between the snap-fit mechanisms J1 (i.e., the concave-convex engaging portion), so that the detachment of the concave-convex engaging portion due to the relative radial displacement can be effectively suppressed. .

Moreover, since the upper end of the upper annular collar 27 is located above the lower end of the engagement piece when the upper and lower cases 10 and 20 are coupled, the outer wall base 13M is displaced radially outward. is effectively suppressed near the engagement piece 21 by the upper annular collar 27 integrated with the upper case 20, thereby further effectively suppressing the detachment of the uneven engagement portion.

Further, in the coupled state between the upper and lower cases 20 and 10 of the embodiment, the inner periphery of the body 23 of the upper case 20 passes through the upper part of the inner wall Wi to the upper part of the pump unit P. Fits and holds the outer periphery. As a result, the upper part of the pump unit P is fitted and held not only by the inner wall Wi but also by the body part 23 across the inner wall Wi, which not only increases the rigidity of the case as a whole, but also increases the rigidity of the case between the upper and lower parts. The bonding strength between 10 and 20 is also increased.

Moreover, since the upper annular collar 27 is integrally connected and supported by the above-mentioned body portion 23 of the upper case 20 via the plurality of support arms 60 to 69, the upper case 20 has a relatively large diameter and high rigidity. To effectively increase the support rigidity of the upper annular collar 27 by the trunk 23 by reducing the radial distance between the trunk 23 and the upper annular collar 27 (that is, the radial length of the support arms 60 to 69) as much as possible. becomes possible.

Further, in the lower case 10 of the embodiment, the lower case side fuel pipe 10p communicating with the fuel discharge pipe 7 and the inner wall Wi are integrally connected to each other and are formed to protrude upward from the case bottom wall portion 12. In this way, the inner wall Wi that regulates the radial displacement of the pump unit P is coupled and integrated with the lower case side fuel pipe 10p, thereby increasing the rigidity of the lower case side fuel pipe 10p and connecting it. Since the radial displacement of the upper case 20 having the upper case side fuel pipe 20p with respect to the lower case 10 can also be effectively suppressed, a snap fit is adopted in which the outer wall Wo of the lower case 10 and the upper case 20 are engaged with each other in a concave and convex manner. The engagement force of the mechanism J1 is strengthened more stably.

Moreover, since the inner wall Wi of the lower case 10 is integrated with the lower case side fuel pipe 10p, the lower case side fuel pipe 10p can be arranged closer to the inner wall Wi, so that the fuel pump module FM This is also advantageous in terms of reducing the diameter.

Although the embodiments of the present invention have been described above, the present invention is not limited to the embodiments described above, and various design changes can be made without departing from the scope of the invention described in the claims. is possible.

For example, in the embodiment described above, the upward step provided on the outer periphery of the outer wall Wo as a standing wall to sandwich the seal ring 41 between the upper annular collar 27 as the annular collar of the present invention is Although shown is a configuration in which the lower annular collar 28 is fitted to the outer periphery, the upward stepped portion of the present invention is constructed by integrally forming the upward stepped portion on the outer periphery of the outer wall Wo instead of using the lower annular collar 28. (i.e., molded) embodiments are also possible.

Furthermore, in the embodiment described above, the lower case 11 is fixed to the tank bottom wall Tb using the stud bolts 14 that protrude downward from the lower surface of the tank bottom wall Tb and pass through the mounting portion 11 of the lower case 10. The structure for fixing the lower case 10 to the tank bottom wall Tb is not limited to the embodiment. For example, by screwing the bolt 14 that liquid-tightly penetrates the tank bottom wall Tb of the mounting portion 11 into a cap nut that is liquid-tightly fixed (for example, welded) to the inner surface of the tank bottom wall Tb, the mounting portion 11 can be attached to the tank bottom. It may be fixed to the wall Tb.

Further, in the above embodiment, the lower case side fuel pipe 10p is integrally connected to the inner wall Wi, but in the present invention, the lower case side fuel pipe 10p is separated from the inner wall Wi (that is, the lower case side fuel pipe 10p is connected to the inner wall Wi). It is also applicable to other embodiments (not directly coupled).

Furthermore, in the embodiment, both the upper and lower cases 20 and 10 are made of synthetic resin, but at least a portion of at least one of the cases may be made of metal.

FM... Fuel pump module P as a fuel supply device... Pump unit T as a fuel pump... Fuel tank Tb... Tank bottom wall Tbc... Outer cylindrical part Tbo. ... Opening Wi in the bottom wall of the tank ... Inner wall Wo ... Outer wall Woa as a standing wall ... Engagement recess 10 ... Lower case 11 ... Mounting part 12 ... - Case bottom wall part 13M... Outer wall base 20 as an inner cylindrical part... Upper case 21at... Engagement convex part 23... Body part 27... Upper annular collar as an annular collar 28...Lower annular collar 40 constituting the upward stepped portion...Seal rings 60 to 69...Support arm

Claims (3)

A mounting part (11) fixed to the tank bottom wall (Tb) of the fuel tank (T), a case bottom wall part (12) that closes the opening (Tbo) of the tank bottom wall (Tb), and the case bottom wall part ( 12) A lower case (10) having an upright wall (Wo) extending inward of the fuel tank (T), and an engagement piece formed along the inside of the upright wall (Wo). (21) and sandwiching the vertically placed fuel pump (P) between the upper case (20) and the lower case (10), the upright wall (Wo) and the engagement piece (21) The upper and lower cases (20, 10) are connected by mutually engaging the engagement recess (Woa) provided on one of them and the engagement protrusion (21at) provided on the other. an outer cylindrical portion (Tbc) that is erected upward on the tank bottom wall (Tb) so as to surround the entire circumference of the opening (Tbo); A seal ring (41) is interposed between the opposing peripheral surface of the inner cylindrical part (13M) surrounded by the cylindrical part (Tbc) over the entire circumference, and seals the gap therebetween. Between an annular collar (27) fitted to the outer circumferential surface of the upright wall (Wo) and an upward step (28) provided on the outer circumference of the upright wall (Wo) below the annular collar (27). In the fuel supply device held between the
The fuel supply device is characterized in that the annular collar (27) is integrally formed with the upper case (20). 1 . The upper end of the annular collar ( 27 ) is located above the lower end of the engagement piece ( 21 ) when the upper and lower cases ( 20 , 10 ) are connected. The fuel supply device described in . The lower case (10) has an inner wall that is located radially inward than the upright wall (Wo) and extends inward from the case bottom wall (12) into the fuel tank (T). (Wi), the fuel pump (P) is fitted to this inner wall (Wi),
The upper case (20) has a body part (23) that fits and holds the upper outer periphery of the fuel pump (P) via the inner wall (Wi) when the upper and lower cases (20, 10) are connected. ), and the upper part of the annular collar (27) is integrally connected to the body (23) via a plurality of support arms (60-69). The fuel supply device described.