JP4751247B2 - Mounting structure of equipment to fuel tank - Google Patents

Description

  The present invention relates to a structure for attaching a device such as a fuel supply module to a main fuel tank and a sub fuel tank in an automobile, a motorcycle, an outboard motor, and the like, and in particular, around the opening of the fuel tank, The present invention relates to an improvement of a structure for mounting a device to a fuel tank, in which a synthetic resin support base of the device to be inserted is attached to seal the opening.

Conventionally, when a synthetic resin member is attached around the opening of a fuel tank, a holding plate that presses the member against the fuel tank is directly fastened to the fuel tank with a bolt (see Patent Document 1).
Japanese Patent Laid-Open No. 10-246335

  Such a synthetic resin member mounting structure has a fuel tank in which a synthetic resin support base of a device inserted into the fuel tank is attached to the periphery of the fuel tank opening to seal the opening. When the equipment is used for the mounting structure of equipment, the weight and vibration of the equipment are constantly applied to the support base, and the thickness of the support base is reduced due to aging of the support base itself. Not only does the support base be unstable, but the sealing of the opening may be impaired.

  The present invention has been made in view of such circumstances, and even if the thickness of the support base is reduced due to aging, etc., the support base is held down by the holding plate and the opening is sealed. An object of the present invention is to provide a structure for mounting an apparatus to the fuel tank.

  In order to achieve the above object, the present invention provides a fuel tank in which a synthetic resin support base of a device inserted into the fuel tank is attached to the periphery of the opening of the fuel tank to seal the opening. In the device mounting structure, the support base that covers the opening and the pressing plate that presses the opening toward the fuel tank are sequentially stacked on the outer surface of the fuel tank, and the end surface passes through the supporting base and the pressing plate. A plurality of bosses projecting out of the press plate are provided on the outer surface of the fuel tank so as to surround the opening, and the press plate is disposed on the fuel tank side between the bolts fastened to the bosses and the press plate. The first feature is that a resilient disc spring is interposed.

  The device corresponds to a fuel supply module Md in an embodiment of the present invention described later.

  In addition to the first feature, the present invention is characterized in that the inner peripheral end of the disc spring is sandwiched between the end surface of the boss and the head of the bolt.

  According to the first feature of the present invention, a plurality of bosses are provided on the outer surface of the fuel tank so as to penetrate the support base and the holding plate on the fuel tank and project the end face outside the holding plate, and fastened to the boss. Since the disc spring that repels the presser plate toward the fuel tank is interposed between the bolt and the presser plate, the support base is subject to the weight and vibration of the equipment, and the wall thickness decreases due to aging, etc. Even if this happens, the elastic force of the disc spring will continue to hold the support base in close contact with the outer surface of the fuel tank via the holding plate, so that the support of the equipment in the fuel tank is always stabilized, The sealed state of the opening of the fuel tank can always be kept good. In particular, the boss penetrates the support base and the presser plate and projects the end face out of the presser plate, so that the fastening force of the bolts screwed to the boss is not transmitted directly to the presser plate but via the disc spring. Therefore, it is possible to avoid excessive pressing against the pressing plate and the support base, and to reduce the thickness reduction due to the aging of the support base.

  According to the second feature of the present invention, by holding the inner peripheral end of the disc spring between the boss and the bolt, it is possible to prevent the disc spring from moving and to constantly stabilize the press of the disc spring against the holding plate.

  Embodiments of the present invention will be described below on the basis of preferred embodiments of the present invention shown in the accompanying drawings.

  1 is a side view of a fuel supply system of a motorcycle equipped with a sub fuel tank to which the present invention is applied, FIG. 2 is an enlarged side view of the sub fuel tank, FIG. 3 is a cross-sectional view taken along line 3-3 of FIG. Is a cross-sectional view taken along line 4-4 of FIG. 3, FIG. 5 is a cross-sectional view taken along line 5-5 of FIG. 3, and FIG.

  First, in FIG. 1, a main fuel tank Tm, a small-capacity sub fuel tank Ts that introduces fuel from the main fuel tank Tm through the first conduit 1A, and a second fuel supply module Md in the sub fuel tank Ts. An engine E, which is supplied with fuel to the fuel injection valve I through the conduit 1B, is mounted on a motorcycle body (not shown). Further, a third conduit 1C for returning the fuel vapor to the main fuel tank Tm extends from the auxiliary fuel tank Ts.

  As shown in FIGS. 2 to 5, the auxiliary fuel tank Ts is made of cast aluminum alloy, and is provided with an opening 2 at the top and a mounting flange 3 projecting on the outer periphery thereof to supply fuel. The module Md is housed in the auxiliary fuel tank Ts through the opening 2 and the support base 4 of the fuel supply module Md is attached to the attachment flange 3 so that the opening 2 is sealed.

  The attachment structure of the support base 4 to the attachment flange 3 will be described with reference to FIGS. A plurality of bosses 5, 5... Arranged in the circumferential direction are integrally projected on the upper surface of the attachment flange 3 of the auxiliary fuel tank Ts, and each boss 5 opens to the upper end surface of the attachment flange 3. A plurality of screw holes 6, 6... Are provided.

On the other hand, the support base 4 is made of a synthetic resin. When the support base 4 is stacked on the mounting flange 3, an O-ring 7A is interposed between the bosses 5, 5,. Further, the support base 4 is integrally provided with a cylindrical portion 4a fitted to the inner peripheral surface of the opening 2 of the auxiliary fuel tank Ts, and between the cylindrical portion 4a and the inner peripheral surface of the opening 2, an O A ring 7B is interposed. On the upper surface of the support base 4, an annular pressure plate 8 made of metal is overlaid. The support base 4 and the pressing plate 8 are provided with a plurality of through holes 9 and 10 penetrating through the plurality of bosses 5, 5. Each boss 5 has a height at which the end surface of the boss 5 penetrating the through holes 9 and 10 protrudes from the upper surface of the pressing plate 8 when the support base 4 and the pressing plate 8 are stacked on the mounting flange 3. The inner peripheral end of the disc spring 11 is fastened to the end surface of the boss 5 by a bolt 12 that is screwed into the screw hole 6, and the disc spring 11 is given elasticity to press the outer peripheral end against the holding plate 8. Has been. Thus, the disc spring 11 is interposed between the head of the bolt 12 and the pressing plate 8, and the support base 4 is held in close contact with the mounting flange 3 by the elastic force against the pressing plate 8. At this time, as shown in the drawing, the inner peripheral end of the disc spring 11 is sandwiched between the head of the bolt 12 and the end surface of the boss 5, suppressing the loose movement of the disc spring 11, and the disc spring 11. As shown in FIGS. 2 and 3, the auxiliary fuel tank Ts is also adjacent to the lower side of the mounting flange 3. A bracket 51 projecting to the side is integrally formed, and this bracket 51 is attached to a support stay 52 attached to the motorcycle body by a bolt 54 via an elastic support member 53.

  Next, the fuel supply module Md will be described with reference to FIGS.

  The fuel supply module M includes the support base 4, an electric pump Mp arranged directly below the support base 4 with the axial direction directed up and down, an upper pump holder 13A formed integrally with the support base 4, In order to hold the electric pump Mp in cooperation with the upper pump holder 13A, the upper pump holder 13A is detachably coupled to the lower pump holder 13B, also made of synthetic resin, and penetrates the bottom wall of the lower pump holder 13B. The fuel strainer S is attached to the lower end of the electric pump Mp, and the fuel strainer S is disposed in the vicinity of the bottom wall of the auxiliary fuel tank Ts.

  The support base 4 made of synthetic resin extends vertically and has a lower end deeply inserted into the auxiliary fuel tank Ts, and communicates with the auxiliary fuel tank Ts to stand on the support base 4. A fuel vapor return pipe 15 and a fuel take-out pipe 16 that communicates with the fuel discharge pipe 30 of the electric pump Mp and stands on the support base 4 are integrally formed. The fuel intake pipe 14 includes a main fuel tank Tm. The first conduit 1A extending from the bottom of the engine is connected, the fuel take-out pipe 16 is connected to the second conduit 1B leading to the fuel injection valve I of the engine E, and the fuel vapor return pipe 15 is connected to the main The third conduit 1C that opens to the upper space in the fuel tank Tm is connected.

  As shown in FIG. 4, the upper pump holder 13A has a cylindrical shape so as to be fitted to the outer peripheral surface of the upper half of the electric pump Mp. The upper pump holder 13A has a T-shape with a lower end opened. A plurality of locking grooves 21m are provided at equal intervals in the circumferential direction. On the other hand, the lower pump holder 13B is formed in a cylindrical shape with a synthetic resin so as to accommodate and hold the lower half of the electric pump Mp. At that time, a plurality of T-shaped locking claws 21f protruding from the upper end are integrally formed. By engaging the locking claw 21f with the locking groove 21m, the lower pump holder 13B is coupled to the upper pump holder 13A. Thus, the electric pump Mp is housed and held between the upper pump holder 13A and the lower pump holder 13B.

  As shown in FIG. 5, the electric pump Mp includes a motor M with the rotor 20 oriented in the vertical direction and a fuel pump P driven by the motor M. The motor M is coupled to a cylindrical stator 17 having a plurality of magnets 17a arranged in the circumferential direction on the inner circumferential surface, an upper bearing bracket 18 that is caulked and coupled to the upper end of the stator 17, and the lower end of the motor M. The lower bearing bracket 19 and the rotor 20 on which the rotor shaft 20a is supported by the upper and lower bearing brackets 18 and 19 are configured.

  The fuel pump P includes a pump case 23 that is caulked to the stator 17 together with the lower bearing bracket 19 so as to define a pump chamber 22 between the lower surface of the lower bearing bracket 19 and a rotor shaft that is rotatably accommodated in the pump chamber 22. The pump impeller 24 connected to the lower end of 20a is configured in a Wesco type.

  The pump case 23 is provided with a suction port 25 that opens to the pump chamber 22, and the fuel strainer S is connected to the suction port 25. The lower bearing bracket 19 is provided with a discharge port 27 that communicates between the pump chamber 22 and the stator 17.

  The upper bearing bracket 18 is integrally formed with a fuel discharge pipe 30 that protrudes upward and has a final discharge port 34 that communicates with the interior of the stator 17, and in which the fuel flows backward to the final discharge port 34. A check valve 31 is provided to prevent this. The fuel discharge pipe 30 is fitted from below to the inner peripheral surface of a connecting cylinder 29 projecting integrally with the lower surface of the support base 4 via a seal member 32.

  The support base 4 includes a series of fuel passages 28 that run inside the fuel take-out pipe 16 and the connecting cylinder 29 and communicate with the inside of the fuel discharge pipe 30, and branch from the fuel passage 28 and have a downstream end at the sub fuel tank. A pressure regulating path 35 is formed in Ts. The pressure adjusting passage 35 is provided with a regulator valve R for adjusting the pressure in the fuel passage 28 to a predetermined pressure suitable for fuel injection from the fuel injection valve I.

  The regulator valve R includes a bottomed cylindrical valve housing 36 formed separately from the support base 4. A valve hole 37 penetrating the valve housing 36 is formed in an end wall of the valve housing 36. A conical valve seat 38 connected to the inner end of 37 is formed. In the valve chamber 42 in the valve housing 36, a ball-type valve body 39 that can be seated on the valve seat 38, and a pressure regulating spring that biases the valve body 39 in a seating direction with the valve seat 38 with a predetermined set load. 40 and an annular retainer 41 that supports the fixed end of the pressure adjusting spring 40 are accommodated. The retainer 41 is press-fitted and fixed to the inner peripheral surface of the valve chamber 42 and is engaged with the opening of the valve chamber 42. The retaining ring 46 is retained by the retaining ring 46.

  The valve housing 36 is fitted and fixed to a holding hole 43 provided in the support base 4 so as to open on the lower surface thereof with the valve hole 37 facing upward, and the valve hole 37 communicates with the pressure regulating path 35.

  The fuel discharge pipe 30 is disposed on one side of the upper end surface of the upper bearing bracket 18, and a power supply terminal 47 of the motor M is projected on the other side, and a coupler terminal 49 connected to the connector 50 connected to the power supply terminal 47. The coupler 48 that holds is integrally projected on the upper surface of the support base 4.

  Next, the operation of this embodiment will be described.

  The inside of the auxiliary fuel tank Ts is always filled with fuel that goes down from the main fuel tank Tm through the first conduit 1A. Accordingly, if the motor M is operated in the fuel supply module Md in the auxiliary fuel tank Ts, the fuel in the auxiliary fuel tank Ts is filtered by the fuel strainer S as the pump impeller 24 is driven by driving the rotor shaft 20a. The air is sucked into the pump chamber 22 from the suction port 25, is pressurized by the pump impeller 24, is pumped into the stator 17 from the discharge port 27, and passes from the final discharge port 34 through the fuel discharge pipe 30, the fuel take-out pipe 16 and the second conduit 1B. The fuel is supplied to the fuel injection valve I and injected from the valve I into the intake passage of the engine E.

  Meanwhile, the pressure of the fuel passage 28, that is, the discharge pressure of the electric pump Mp acts on the valve body 39 of the regulator valve R from the pressure adjusting passage 35. Therefore, when the discharge pressure of the electric pump Mp exceeds a predetermined value, the valve body 39 is When the pressure regulating spring 40 is opened against the set load, a part of the fuel in the fuel passage 28 is discharged to the auxiliary fuel tank Ts, and when the pressure in the fuel passage 28 returns to a predetermined value, the valve body 39 is adjusted. The valve is closed again by the set load of the pressure spring 40. Thus, the pressure in the fuel passage 28 is automatically adjusted to a predetermined value, so that the fuel injection pressure from the fuel injection valve I is properly controlled.

  When fuel vapor is generated in the auxiliary fuel tank Ts, it goes up through the third conduit 1C and returns to the upper space of the main fuel tank Tm. After cooling and liquefaction, it is stored again in the main fuel tank Tm.

  By the way, a pressing plate 8 is stacked on the upper surface of the synthetic resin support base 4 of the fuel supply module Md, which is stacked on the mounting flange 3 of the sub fuel tank Ts, and the end surface penetrates through the support base 4 and the pressing plate 8. Bolts 12 are fastened to a plurality of bosses 5 of the mounting flange 3, and a disc spring 11 is interposed between the bolts 12 and the press plate 8. Since the support base 4 is held in close contact with the mounting flange 3 through the holding plate 8 by the elastic force of the power, the support base 4 is subjected to the weight and vibration of the electric pump Mp and other parts, and is subject to change due to secular change. Even if the thickness is reduced, the elastic force of the disc spring 11 continues to hold the support base 4 in close contact with the mounting flange 3 via the presser plate 8, and therefore the fuel supply module. With always stabilize the support of Le Md, it is possible to maintain the sealed state of the opening 2 of the auxiliary fuel tank Ts always good.

  In particular, the boss 5 penetrates through the support base 4 and the pressing plate 8 so that the end surface protrudes outside the pressing plate 8, so that the fastening force of the bolt 12 screwed to the boss 5 can be directly transmitted to the pressing plate 8. However, since transmission is performed via the disc spring 11, excessive press against the presser plate 8 and the support base 4 can be avoided, and thickness reduction due to aging of the support base 4 can be mitigated.

  The present invention is not limited to the above embodiment, and various design changes can be made without departing from the scope of the invention. For example, according to the present invention, the fuel supply module Md can be attached to the main fuel tank Tm.

1 is a side view of a fuel supply system of a motorcycle including an auxiliary fuel tank to which the present invention is applied. The enlarged side view of the said auxiliary fuel tank. 3-3 sectional view of FIG. FIG. 4 is a sectional view taken along line 4-4 of FIG. FIG. 5 is a sectional view taken along line 5-5 of FIG. FIG. 6 is an enlarged view of 6 parts in FIG. 4.

Explanation of symbols

Ts ... Fuel tank Md ... Equipment (fuel supply module) 2 ... Opening 3 ... Mounting flange 4 ... Support base 5 ... Boss 8 ... Presser plate 9 ... Through hole 10 ... Through hole 11 ... Belleville spring 12 ... Bolt

Claims (2)

A synthetic resin support base (4) of a device (Md) inserted into the fuel tank (Ts) from the opening (2) is attached around the opening (2) of the fuel tank (Ts). (2) In the structure for mounting the equipment to the fuel tank,
On the outer surface of the fuel tank (Ts), the support base (4) that covers the opening (2) and a pressing plate (8) that holds the support base (4) on the fuel tank (Ts) side are sequentially stacked. ) And a plurality of bosses (5) penetrating the holding plate (8) and projecting the end face out of the holding plate (8) projecting from the outer surface of the fuel tank (Ts) so as to surround the opening (2), Between the bolt (12) fastened to these bosses (5) and the pressing plate (8), a disc spring (11) is provided for repelling the pressing plate (8) toward the fuel tank (Ts). A structure for mounting equipment to a fuel tank. In the structure for attaching the device to the fuel tank according to claim 1,
A structure for attaching a device to a fuel tank, characterized in that an inner peripheral end of the disc spring (11) is sandwiched between an end face of the boss (5) and a head of the bolt (12).

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