Title of Invention

TANK FITTING STRUCTURE FOR FUEL PUMP

Abstract

To provide a fitting structure for a fuel pump in place of snap fit or bayonet connection. [Solving Means] A nut 50 is fastened onto a bolt 31, whereby a second valley portion 41 is brought into close contact with a first mount portion 33, as is shown. At this time, gasket 35 is appropriately collapsed by a presser ring 40 through a flange portion 21, so that sealing performance of the gasket 35 can be displayed sufficiently. [Effects] There is no fear that a compressing force in excess of a certain level would be exerted on the flange portion, so that generation of creep can be obviated even when the flange portion is made of a resin.

Full Text

FORM 2 THE PATENTS ACT 1970 [39 OF 1970] COMPLETE SPECIFICATION [See Section 10] "TANK FITTING STRUCTURE FOR FUEL PUMP" HONDA GIKEN KOGYO KABUSHIKI KAISHA, a corporation of Japan, having a place of business at 1-1, Minamiaoyama 2-chome, Minato-ku, Tokyo, Japan, The following specification particularly describes the nature of the invention and the manner in which it is to be performed:- [Detailed Description of the Invention] [0001] [Technical Field of the Invention] The present invention relates to an improvement in a tank fitting structure for a fuel pump. [0002] . [Prior Art] For example, Fig. 4 of Japanese Pre-examination Patent Publication (KOKAI) No. 8-232792 (1996) "In-tank Type Fuel Pump Device" shows the condition where an in-tank type fuel pump 2 is fitted to a fuel tank 1 (as for the symbols, the same numerals as in the publication are used,"here and hereinafter), and a fitting structure of a flange 24 of the in-tank type fuel pump 2 is shown in detail in Fig. 31 of the publication. Fig. 31 will be reprinted in the following figure, and the structure will be described in detail. The symbols have been renewed. [0003] Figs. 14(a) to 14(c) are reprint of Fig. 31 of the Japanese Pre-examination Patent Publication (KOKAI) No. 8-232792 (1996) and illustrations of mounting, in which 14(c) coincides with Fig. 31, and 14(a) and 14(b) are illustrations of mounting to obtain 14 (c) . In Fig.14(a), a presser claw 102 is preliminarily fitted" to an edge of a pump insertion hole 101 of a fuel tank 100, and a gasket 103 is put on the edge of the pump insertion hole 101. On the other hand, an earth minus terminal 106 is fitted to a rib 105 drooped down from a flange 104 of the pump, and the flange 104 is put on the gasket 103 (arrow 1) . [0004] Fig. 14(b) shows the condition where the flange 104 is put on the gasket 103, and, while pushing the flange 104 as indicated by the void arrow, a stopper metal 107 is lowered to a side of the presser claw 102 as indicated by arrow ©, and is turned as indicated by arrow ®, whereby the stopper metal 107 is hooked on the presser claw 102. Fig. 14(c) shows completion of mounting, in which the gasket 103 has an action of pushing up the flange 10,4, and, by pressing the flange 104 by the stopper metal 107, the flange 104 is fitted to the fuel tank 100 while maintaining a sealing property. [0005] The connecting structure of hooking by turning the stopper metal 107 onto the presser claw 102 on the fixed side is called snap fit or bayonet connection, which is a simple connecting method and is widely adopted. [0006] •[Problems to be Solved by the Invention] However, as is clear from Fig. 14(c), the simple structure leads to dispersion in the collapsing amount of the gasket 103, and problems remain in the case of, for example, an autobicycle which receives large vibrations. [0007]" As a countermeasure, it may be contemplated to increase the size of the gasket 103 to increase the collapsing allowance or to form the gasket 103 from a hard material to enhance the spring coefficient. When such a countermeasure is adopted, the pressing force indicated by the void arrow in Fig. 14(b) is increased, so that the presser claw 102 and the stopper metal 107 must be rigid, leading to an increase in parts cost. In addition, the turning torque of the stopper metal 107 indicated by arrow (3) in Fig. 14(b) is increased, whereby the mounting work is made to be difficult. [0008] Besides, for lightness in weight and corrosion resistance, the flange 104 may sometimes be made of a resin. Resins suffer from deformation called creep when being compressed with a high pressure for a long time. Therefore, the increase in pressing force has a limitation. Further, in view of design of a fuel tank for an autobicycle, in many cases the pump unit is inserted into a tank bottom upwards from the lower side, and fixed. In such a case, the center of gravity of the pump unit is upper than the flange, so that a large force is exerted on the flange at the time of lateral swinging. The snap fit or bayonet connection is not said to be suitable for such use. From the above-mentioned grounds, the pump fitting structures according to the prior art are not suitable for vehicles receiving" large vibrations such as an autobicycle. Accordingly, it is an object of the present invention to provide,a fitting structure for a fuel pump which replaces the snap fit" or bayonet connection. [0010] [Means for Solving the Problems] In order to .attaint he above object, the present invention comprises a tank fitting structure for a fuel pump, comprising a gasket (35) put on an edge of a pump insertion hole (12) provided in a fuel tank (10), a fixed side ring (30) preliminarily fitted to said fuel tank (10) at a position for surrounding said gasket (35),a major part of a pump unit (20) inserted into said fuel tank (10) through said pump insertion hole (12) while placing a flange portion (21) projected from said pump unit (20) on said gasket (35),a presser ring (40) having an inside surface and an outer surface, wherein the inside surface of the presser ring (40) is put on said flange portion (21); and an outside surface of said presser ring (40) is caused to face said fixed side ring (30), wherein said outside surface of said presser ring (40) is brought into close contact with said fixed side ring (30) by a fastening member (31), whereby said pump unit (20) is fitted to said fuel" tank (10)and wherein said fixed side ring (30), is a formed ring comprising first valley portions and first mount portions alternately "provided by bending a steel sheet, said first valley portions connected to said fuel tank (10) , and said first mount portions used as receiving surfaces for said presser ring (40), and said presser ring (40) is a formed ring comprising second valley portions and second mount portions alternately provided by bending a steel sheet, said second valley portions brought into contact with said first mount portions, and said flange portion (21) of said pump unit (20) held by inside surfaces of said second mount portions. The gasket is put on the flange portion, and the flange portion is pressed by an inside surface of the presser ring to thereby collapse the gasket, when the collapsing amount is determined at the position where the presser ring comes into contact with the fixed side" ring. Namely, the collapsing amount of the gasket is not varied even if the fastening force of the fastening member is more increased," and only the connection between the fixed side ring and the presser ring is augmented. A compressing force acting on the flange portion coincides with the springy force of the gasket. According to the present invention, the springy force of the gasket is fixed, so that there is no fear that a compressing force beyond a certain level would be exerted on the flange " portion, and generation of creep can be obviated even where the flange portion is made of a resin. Namely, sealing performance is stabilized, so that good sealing performance can be maintained even under vibrations. [0012] Claim is characterized in that the fixed side ring is a formed ring comprising first valley portions and first mount portions alternately provided by bending a steel sheet, the first valley portions connected to the fuel tank, and the first mount portions used as receiving surfaces" for the presser ring, and the presser ring is a formed ring comprising second valley portions and second mount portions alternately provided by bending a steel sheet, the second valley portions brought into contact with the first mount portions, and the flange portion of the pump unit held by inside surfaces of the second mount portions. [0013] In order to bring the presser ring into close contact with the fixed side ring and to appropriately press the flange portion by the presser ring, desired shapes are arranged by bending a sheet. Since formed rings made from a sheet are adopted, a reduction in weight of the fixed side ring and the presser ring can be contrived. [0014] Claim ^is characterized in that the flange portion of the pump unit is formed of a resin. [0015] According to the present invention, the flange portion can"be made of a resin. As a result, reductions in weight and cost of the pump unit can be contrived. — [Brief Description--of the Drawings] [Fig. 1] ...A conceptual illustration-of a fuel tank and a pump unit according to the present" invention. [Fig.- 2] An exploded view of a tank fitting structure for a pump unit according to the present invention (First Embodiment). [Fig. 3] A plan view of a fixed side ring according to the present invention (First Embodiment) . -[Fig. 4] -A-view taken along arrow 4 of Fig. 3. [Fig. 5] A plan view of a presser ring according to the present invention (First Embodiment). [Fig. 6] A view taken along arrow 6 of Fig. 5. [Fig. 1] A view showing a tank fitting procedure for a fuel pump according to the present invention (First Embodiment). [Fig. 8] A view taken along arrow 8 of Fig. 7. [Fig. 9] A view showing a tank fitting structure for a fuel tank according to the present invention (First Embodiment). [Fig. 10] A perspective view of a fixed side ring and a presser ring according to Second Embodiment of the present invention. [Fig. 11] A view showing a tank fitting procedure for a fuel pump according to the present invention (Second Embodiment). [Fig. 12] A perspective view of a fixed side ring and a presser ring according to Third Embodiment of the present invention. [Fig. 13] A view showing a tank fitting procedure for a fuel tank according to the present invention (Third Embodiment). [Fig. 14] A reprint of Fig. 31 of Japanese Pre-examination Patent Publication (KOKAI) No. 8-232792 (1996) and an illustration of mounting. [0016] [Mode for Carrying out the Invention] A mode for carrying out the present invention will be described referring to the attached drawings: Fig. 1 is a conceptual illustration of a fuel tank and a pump unit according to the present invention, in which a pump unit 20 is fitted, as indicated by arrow (H), to a fuel tank 10 for autobicycle provided with a fuel feed cap 11 at an upper portion. Namely, with a flange portion 21 directed downwards, the pump unit 20 is inserted upwards to thereby fit the pump unit 20 to a fuel tank 10. This is for maintaining the design property of the fuel tank 10. In the following description, the pump unit 20 is inverted upside down for convenience. [0017] Fig. 2 is an exploded view of a tank fitting structure for a pump unit according to the present invention (First Embodiment). The tank fitting structure for the pump unit comprises a pump insertion hole 12 provided in the fuel tank 10, a fixed side ring 30 fitted to the fuel tank 10 in the manner of surrounding the pump insertion hole 12, bolts 31 • • • • • -means a plurality, here and hereinafter) as part of the fastening member fitted by welding to the fixed side ring 30, a gasket 35, the pump unit 20 provided with the flange portion 21, a presser ring 40, and nuts-50 • "* * as the remainder of the fastening member. [0018] Describing the pump unit 20 briefly, a motor pump and a strainer (both not shown) are incorporated in a resin-made pump case 22 provided integrally with the flange portion 21, and a fuel sucked in through a port 23 is pressurized by the motor pump, is filtered through the strainer, and is ejected through a discharge port 24. Numeral 25 denotes a cover, and 26 denotes a connector fitting port. [0019] Fig. 3 is a plan view of the fixed side ring according to the present invention (First Embodiment), and Fig. 4 is a view taken along arrow 4 of Fig. 3. The fixed side ring 30 comprises pluralities (for example, 6) of first valley portions 32 • • • and first mount portions 33 • • • alternately provided by press punching and bending of a steel sheet, and has an inside diameter Dl greater than the outside diameter of the gasket 35 (See Fig. 2). Each of the first mount portions, 33 is provided with a bolt hole 34, and the bolt 31 is inserted in the bolt hole 34 from the lower side. A head 31a of the bolt 31 is preliminarily provided with a small projection for projection welding/ and an electric current is passed while the small projection is kept in contact with the lower side of the first mount portion 33 to concentrate the current to the small projection, whereby welding is achieved. Such a welding method is called projection welding method. [0020] Fig. 5 is a plan view of a presser ring according to the present invention (First Embodiment), and Fig. 6 is a view taken along arrow 6 of Fig. 5. The presser ring 40 is a formed product comprising pluralities (for example, 6) of second valley portions 41 • • • and second mount portions 42 "• • alternately provided by punching and bending a steel sheet, with a presser piece portion 43 projected toward the center from each of the second mount portions 42. The second valley portions 41 • • are provided with bolt holes 44 • • • . The minimum inside diameter D2 is smaller than the diameter of the flange portion 21 (See Fig. 2) of the pump unit,20, and the inside diameter D3 between the second valley portions 41, 41 is slightly greater than the diameter of the flange portion 21 (See Fig. 2). [0021] While six presser piece portions 43 are intermittently provided in the figure, the presser piece portions 43 • • • may be contiguous with each other so that, namely, the presser ring 40 has an inside diameter D2 uniformly. However, where the presser piece portions 43 are intermittently provided as shown in the figure, it is possible to obviate generation of wrinkles at the time of press working, so that press forming is facilitated, and production cost can be reduced. [0022] Action or effect of the fixed side ring and the presser ring according to First Embodiment described above will be described referring to Figs. 7 to 9. Fig. 7 is a tank fitting procedure of a fuel pump according to the present invention (First Embodiment). The gasket 35 is put on an edge of the pump insertion hole 12 provided in the fuel tank 10, the fixed side ring 30 is preliminarily fitted to the fuel tank 10 at a position for surrounding the gasket 35, and a major part of the pump unit 20 is inserted into the fuel tank 10 through the pump insertion hole 12 while placing the flange portion 21 projected from the pump unit 20 on the gasket 35. Next, while the inside surface 45 (corresponding to the lower surface of the presser piece portions 43) of the presser ring 40 is caused to front on the flange portion 21, a bolt hole 44 of the presser ring 40 is fitted to the bolt 31, whereby the outside surface 46 of the presser ring 40 is caused to front on the fixed side ring 30. [0023] Fig. 8 is a view taken along arrow 8 of Fig. 7, and shows the condition where the first valley portions 32, 32 of the fixed side ring 30 are preliminarily welded to the fuel tank 10, and the second valley portion 41 of the presser ring 40 is caused to front on the first mount portion 33 of the fixed side ring 30. [0024] Fig. 9 is a view showing the tank fitting structure for the fuel tank according to the present invention (First Embodiment), and shows the condition where the second valley portion 41 is brought into close contact with the first mount portion 33 by fastening the nut 50 onto the bolt 31. At this time, the gasket 35 is appropriately collapsed by the presser piece portion 43 of the presser ring 40 through the flange portion 21, so that sealing performance of the gasket 35 can be displayed sufficiently. [0025] Here, it is important that even when the nut 50 is fastened more, the collapsing amount of the gasket 35 is not substantially changed, because the second valley portion 41 is in contact with the first mount portion 33. Namely, strongly fastening the nut 50 is necessary for increasing the fastening force of the fixed side ring 30 and the presser ring 40, but the collapsing amount of the gasket 35 is not affected by the action of increasing the fastening force. [0026] The collapsing amount of the gasket 35 has an optimum value determined according to the material and cross - sectional shape. If the collapsing amount is" deviated from the optimum value by more than a certain value, reduction of the sealing performance or breakage of the gasket will occur. In view of this, according to the present invention, the collapsing amount of the gasket 35 can be maintained at a fixed level, so that good sealing performance can be maintained. Since the collapsing amount of the gasket 35 is fixed, the compressing force acting on the flange portion 21 is fixed. Since there is no fear that the compressing force is abruptly increased, the flange portion 21 can be made from a resin. [0027] In addition, the presser ring 40 can be securely fastened to the fixed side ring 30 by the bolt 31 and the nut 50 as fastening members, and there is no fear that the fastening members are loosened even when receiving vibrations. Therefore, the fitting structure according to the present invention is suitable for a tank fitting structure for a fuel pump in an autobicycle which would receive large vibrations, particularly for the case where the pump unit 20 is inserted into the fuel tank 10 from the lower side as shown in Fig. 1. However, this fitting structure may also be applied to three- or four-wheel vehicles. [0028] Another embodiment of the present invention will next be described. Fig. 10 is a perspective view of a fixed side ring and a presser ring according to Second Embodiment of the present invention. The fixed side ring 30 is a steel plate ring with bolts 31 fitted thereto in an upward pose, and the presser ring 40 is a steel plate ring having, bolt holes 44 • • • and a presser piece portion 43. [0029] Figs. 11(a) and 11(b) are views of tank fitting procedure for a fuel tank according to the present invention (Second Embodiment). In Fig. 11(a), a gasket 35 is put on an edge of a pump insertion hole 12 provided in a fuel tank 10, the fixed side ring 30 is preliminarily fitted to the fuel tank 10 at a position for surrounding the gasket 35, and a major part of a pump unit 20 is inserted into the fuel tank 10 through the pump insertion hole 12 while placing a flange portion 21 projected from the pump unit 20 on the gasket 35. Next, the bolt hole 44 of the presser ring 40 is. fitted to the bolt 31 while causing the inside surface 45 (corresponding to the lower surface of the presser piece portion 43) of the presser ring 40 to front on the flange portion 21, whereby the outside surface 46 of the presser ring 40 is caused to front on the fixed side ring 30. [0030] In Fig. 11(b), a nut 50 is fastened onto the bolt 31, whereby the presser ring 40 is brought into close contact with the fixed side ring 30. By this, the gasket 35 is appropriately collapsed by the presser ring 40 through the flange portion 21, so that sealing performance of the gasket 35 can be displayed sufficiently. [0031] Fig. 12 is a perspective view of a fixed side ring and a presser ring according to Third Embodiment of the. present invention. The fixed side ring 30 is a steel plate ring provided with legs 37 , with bolts 31 fitted thereto in an upward pose, and the presser ring 40 is a steel plate ring having bolt holes 44 and a presser piece portion 43. With the fixed side ring 30 provided with the legs 37 , reductions in material thickness and weight of the fixed side ring 30 can be achieved. [0032] Figs. 13(a) and 13(b) are views showing the tank fitting procedure of a fuel pump according to the present invention (Third Embodiment). In Fig. 13 (a) , a gasket 35 is put on an edge of a pump insertion hole 12 provided in the fuel tank 10, a fixed side ring 30 is preliminarily fitted to the fuel tank 10 at a position for surrounding the gasket 35, and a major part of a pump unit 20 is inserted into the fuel tank 10 through a pump insertion hole 12 while placing a flange portion 21 projected from the pump unit 20 on the gasket 35. Next, the bolt hole 44 of the presser ring 40 is fitted to the bolt 31 while causing the inside surface 45 (corresponding:to the lower surface of the presser piece portion 43) of the presser ring 40 to front on the flange portion 21, whereby the outside surface 46 of the presser ring 40 is caused to front on the fixed side ring 30-. [0033] In Fig. 13(b), a nut 50 is fastened onto the bolt 31, whereby the presser ring 40 is brought into close contact with the fixed side ring 30. By this, the gasket 35 is appropriately collapsed by the presser ring 40 through the flange portion 21, so that sealing performance of the gasket 35 can be displayed sufficiently. [0034] The fastening member exemplified by the bolt 31 and the nut 50 may be any member of any kind that can display an action of pressing the presser ring against the fixed side ring. The fitting structure according to the present invention can be applied to any of a system in which the pump unit is inserted into the fuel tank downwards from the upper side, a system in which the pump unit is inserted into the fuel tank upwards from the lower side, and a system in which the pump unit is inserted intot the fuel tank in a lateral- direction. [0035] [Effects of the Invention] The present invention, with the above constitution, displays the following effects. According to claim 1, a flange portion is placed on a gasket put on an edge of a pump insertion hole of a fuel tank, and the gasket is collapsed by pressing the flange portion by the inside surface of a presser ring, where the collapsing amount is determined at a position where the presser ring comes into contact with a fixed side ring. Namely, even if the fastening force of a fastening member is increased more, the collapsing amount of the gasket is not changed, and only the connection between the fixed side ring and the presser ring is augmented. A compressing force exerted on the flange portion coincides with the springy force of the gasket. According to the present invention, the springy force of the gasket is fixed, so that there is no fear that a compressing force more than a certain level would be exerted on the flange portion, so that it is possible to obviate generation of creep even when the flange portion is made from a resin. Namely, sealing performance is stabilized, so that good sealing performance can be maintained even un"der vibrations. [0036] Claim $ is characterized in that the fixed side ring is a formed ring comprising first valley portions and first mount portions alternately provided by bending a steel sheet, the first valley portions connected to the fuel tank, and the first mount portions used as receiving surfaces for the presser ring, and the presser ring is a formed ring comprising second valley portions and second mount portions alternately provided by bending a steel sheet, the second valley portions brought into contact with the first mount portions, and the flange portion of the pump unit held by inside surfaces of the second mount portions. In order to bring the presser ring into close contact with the fixed side ring and to appropriately hold the flange portion by the presser ring, desired shapes are adjusted by bending a sheet. Since the formed rings made of sheet are adopted, a reduction in weight of the fixed side ring and the presser ring can be contrived. [0037] Claim 2 is characterized in that the flange portion of the pump unit is formed from a resin, whereby the flange portion can be formed of resin. As a result, reductions in weight and cost of the pump unit can be contrived. [Description of Reference Numerals] 10: fuel tank; 12 : pump insertion hole; 20: pump unit; 21: flange"portion; 30: fixed side ring; 31: fastening member (bolt); 32: first valley portion; 33: first mount portion; 35: gasket; 40: presser ring; 41: second valley portion; 42: second mount portion; 45: inside portion; 46: outside portion; 50: fastening member (nut) . We claim 1. A tank fitting structure for a fuel pump, comprising a gasket (35) put on an edge of a pump insertion hole (12) provided in a fuel tank (10); a fixed side ring (30) preliminarily fitted to said fuel tank (10) at a position for surrounding said gasket (35); a major part of a pump unit (20) inserted into said fuel tank (10) through said pump insertion hole (12) while placing a flange portion (21) projected from said pump unit (20) on said gasket (35); a presser ring (40) having an inside surface and an outer surface, wherein the inside surface of the presser ring (40) is put on said flange portion (21); and an outside surface of said presser ring (40) is caused to face said fixed side ring (30); wherein said outside surface of said presser ring (40) is brought into close contact with said fixed side ring (30) by a fastening member (31), whereby said pump unit (20) is fitted to said fuel tank (10); and wherein said fixed side ring (30) is a formed ring comprising first valley portions and first mount portions alternately provided by bending a steel sheet, said first valley portions connected to said fuel tank (10), and said first mount portions used as receiving surfaces for said presser ring (40), and said presser ring (40) is a formed ring comprising second valley portions and second mount portions alternately provided by bending a steel sheet, said second valley portions brought into contact with said first mount portions, and said flange portion (21) of said pump unit (20) held by inside surfaces of said second mount portions. 2. A tank fitting structure for a fuel tank (10) as claimed in claim 1, wherein said flange portion (21) of said pump unit (20) is formed of a resin. 3. A tank fitting structure for a fuel tank (10) as claimed in claim 1, wherein the inside surface of the second mount portions is the presser piece portions which are formed intermittently. 4. A tank fitting structure for a fuel pump substantially as herein described with reference to the accompanying drawings. Dated this 28th day of May, 2002. [RAJAN AILAV OF REMFRY & SAGAR ATTORNEY FOR THE APPLICANTS

Documents:

1185-mum-2001-abstract-(16-01-2008).doc

1185-mum-2001-abstract-(16-01-2008).pdf

1185-mum-2001-abstract.doc

1185-mum-2001-abstract.pdf

1185-mum-2001-cancelled pages-(16-01-2008).pdf

1185-mum-2001-cirtificate.pdf

1185-mum-2001-claims(granted)-(16-01-2008).doc

1185-mum-2001-claims(granted)-(16-01-2008).pdf

1185-mum-2001-claims.doc

1185-mum-2001-claims.pdf

1185-mum-2001-correspondence(18-01-2008).pdf

1185-mum-2001-correspondence(ipo)-(08-02-2008).pdf

1185-mum-2001-correspondence(ipo).pdf

1185-mum-2001-correspondence.pdf

1185-mum-2001-description(granted).doc

1185-mum-2001-description(granted).pdf

1185-mum-2001-drawing.pdf

1185-mum-2001-form 1-(18-12-2001).pdf

1185-mum-2001-form 1.pdf

1185-mum-2001-form 18-(09-12-2005).pdf

1185-mum-2001-form 18.pdf

1185-mum-2001-form 2(granted)-(16-01-2008).doc

1185-mum-2001-form 2(granted)-(16-01-2008).pdf

1185-mum-2001-form 2(granted).doc

1185-mum-2001-form 2(granted).pdf

1185-mum-2001-form 2(title page).pdf

1185-mum-2001-form 3-(18-12-2001).pdf

1185-mum-2001-form 3-(27-03-2002).pdf

1185-mum-2001-form 3.pdf

1185-mum-2001-form 5-(18-12-2001).pdf

1185-mum-2001-form 5.pdf

1185-mum-2001-power of attorney(4-05-2007).pdf

1185-mum-2001-power of attorney.pdf

1185-mum-2001-power of authority-(04-05-2007).pdf

1185-mum-2001-power of authority-(14-03-2002).pdf

1185-mum-2001-u.s patent.pdf

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