In tank fuel pump mounting arrangement

A fuel supply device includes a cover member attached to an opening of a fuel tank, a pump unit including a pump, and a connecting portion which connects the cover member and the pump unit. The pump unit is connected so as to be relatively movable with respect to the connecting portion when a connecting shaft which is formed as part of one of the connecting portion or the pump unit, is inserted into the connecting hole formed as part of the other of the two. The connecting hole has an elongated hole portion that allows the connecting shaft to move in the upward and downward directions, and allows the pump unit to be relatively movable with respect to the connecting portion. The pump unit includes an engagement portion abutting a lower terminal end of the connecting portion when the fuel supply device is attached to the fuel tank.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is a National Phase entry of, and claims priority to, PCT Application No. PCT/JP2015/072658, filed Aug. 10, 2015, which claims priority to Japanese Patent Application No. 2014-171444, filed Aug. 26, 2014, both of which are incorporated by reference herein in their entireties for all purposes.

Not applicable.

BACKGROUND

The present disclosure relates to a fuel supply device. In particular, the disclosure relates to a fuel supply device for supplying fuel within a fuel tank to an internal combustion engine, wherein the fuel supply device is mounted to a vehicle, e.g. an automobile.

Fuel supply devices mounted to fuel tanks are widely known in the art. It is also widely known that a part of the fuel supply device can be inserted from an opening formed in an upper surface portion of the fuel tank, where the device attaches to said opening when the fuel supply device is mounted to the fuel tank. Further, as disclosed in a Japanese Laid-Open Patent Publication No. 2012-184760 (hereinafter referred to as 760 Publication), a pump unit rotatably provided to a fuel supply device is also known.

BRIEF SUMMARY

However, the prior art disclosed in 760 Publication can still be further improved. According to the fuel supply device disclosed in the 760 Publication, a pump unit may be rotatably mounted to the connecting portion when a connecting shaft provided as part of the pump unit is inserted through a connecting hole. The prior art was not configured such that the force transmitted from the connecting portion presses the pump unit to the fuel tank. Therefore, it could not maintain a state in which the pump unit abuts the fuel tank. Particularly, the prior art could not maintain a state in which the pump unit abuts the fuel tank when a tank bottom surface is inclined as the fuel tank was deformed. As a result, the fuel within the fuel tank could not be used effectively.

Therefore, there is a need for a fuel supply device configured to maintain a pump unit provided as part of the fuel supply device to abut a fuel tank even if the bottom surface of the fuel tank is deformed to be inclined while the fuel supply device is mounted to said fuel tank.

According to one aspect of the present disclosure, a fuel supply device comprises a cover member which is attached to an opening of a fuel tank as well as a pump unit having a pump, and a connecting portion connecting the cover member and the pump unit. The pump unit is connected so as to be relatively movable with respect to the connecting portion when a connecting shaft which is formed as part of one of the connecting portion or the pump unit, is inserted into a connecting hole which is formed as part of the other of the two. The connecting hole has an elongated hole portion that allows the connecting shaft to be relatively movable in the upward and/or downward directions relative to the connecting hole. An engagement portion is provided at the pump unit abutting an end (e.g. a lower end) of the connecting portion when the fuel supply device is attached to the fuel tank.

Therefore, through the abutment, the engagement portion provided at the pump unit can always receive a pressing force from the connecting portion when the fuel supply device is mounted to the fuel tank. Further, since the connecting hole is formed as an elongated hole, a movable range of the connecting shaft is larger than that known in conventional art. Thus, through the expanded range, the flexibility of the relative positional relationship between the connecting portion and the pump unit is increased, and the pump unit can be pressed against the fuel tank by the connecting portion. In this manner, the pump unit can be pressed against the fuel tank even when the fuel tank is deformed to be inclined to follow to the deformation of the fuel tank.

According to another aspect of the present disclosure, the end (e.g. lower end) of the connecting portion has a planar part which can abut the engagement portion, as well as an arcuate curved surface as seen from a side view, which extends from the planar part.

Therefore, the engagement portion can be pressed by the planar portion when the fuel tank is not deformed. The engagement portion can be pressed by the curved surface when the fuel tank is deformed to be inclined. Consequently, through said planar and arcuate parts at its lower end, the connection portion can press the engagement portion with relatively good followability to the deformation of the fuel tank.

According to another aspect of the present disclosure, a fuel supply device comprises a cover member which is attached to an opening of a fuel tank, as well as a pump unit comprising a pump, and a connecting portion for connecting the cover member and the pump unit. The pump unit is connected so as to be relatively movable with respect to the connecting portion when a connecting shaft which is formed as part of one of the connecting portion or the pump unit, is inserted into the connecting hole which is formed in the other of the two. An engagement portion is provided as part of the pump unit, where the engagement portion abuts an end (e.g. lower end) of the connecting portion when the fuel supply device is attached to the fuel tank. The end (e.g. lower end) of the connecting portion has a circular arc curved surface positioned directly below the connecting shaft.

Accordingly, the engagement portion can be pressed by one part of the curved surface of the lower end of the connecting portion when the fuel tank is not deformed, and can be pressed by the other part of the curved surface when the fuel tank is deformed to be inclined. Consequently, through said pressing, the end of the connection portion can press the engagement portion with relatively good followability to the deformation of the fuel tank.

DETAILED DESCRIPTION

Hereinafter, one exemplary embodiment of the present disclosure will now be described with reference to the drawings. The forward and backward directions, upward and downward directions as well as the leftward and rightward directions in the present specification are determined such that X is a forward direction, Y is a leftward direction and Z is an upward direction as shown inFIG. 1, where the backwards, leftwards, and downwards directions extend in the negative direction of X, Y, and Z, respectively. A cover member2of a fuel supply device1is positioned at an upper side and a pump unit4is positioned at a lower side of the device. A rotary axis of the pump unit4extends in the leftward-to-rightward direction, parallel to the y axis. The forward and backward directions are orthogonal to the leftward and rightward directions as well as the upward and downward directions.

The fuel supply device1according to the present embodiment may be mounted on a vehicle, such as an automobile. The fuel supply device1may be attached to a fuel tank7arranged below a floor of the vehicle. The fuel supply device1is used to feed liquid fuel stored within the fuel tank7to an internal combustion engine (not shown).

As shown inFIGS. 1 to 3, the fuel supply device1according to the present embodiment has the cover member2attached to an opening72formed within an upper surface71of the fuel tank7and a pump unit4with a pump41which may be used for feeding fuel within the fuel tank7to the outside. Further, the fuel supply device1includes a connecting portion3aused for connecting the cover member2to the pump unit4. When the fuel device is attached to the fuel tank, the pump unit4lies proximal to the bottom surface73of the fuel tank7whereas the cover member2is attached to the opening72of the fuel tank7. The cover member2can close the opening72of the fuel tank7and press the pump unit4along the bottom surface73of the fuel tank7.

The cover member2includes a set plate portion21which covers the opening72of the fuel tank7. An outlet port23is provided on the substantially disk-shaped set plate portion21for leading fuel delivered from the pump unit4to the outside of the fuel tank7. Further, the set plate portion21includes an electric connector24(not shown) for connecting electric wiring. The opening72normally has a circular shape, and the set plate portion21has a substantially circular shape in a plan view, which is concentric with and thus corresponds to the shape of the opening72. A ring made of resin (not shown) is attached to the opening72and acts as a sealing member, filling a clearance between the fuel tank7and the cover member2in order to reduce or eliminate the clearance.

As shown inFIGS. 1 and 2, the pump unit4is arranged below the cover member2. The pump unit4includes the pump41used for feeding fuel and a base portion42used for mounting the pump41. The base portion42has a substantially flat plate shape and is arranged so that one surface of the base portion42faces the bottom surface73of the fuel tank7. The base portion42may also be referred to as a fuel reservoir or a sub-tank etc. The base portion42includes an upper base421to which the pump41is attached, a lower base422which faces and contacts the bottom surface73of the fuel tank7, and a filter member423which is interleaved between the upper base421and the lower base422. The upper base421is provided with a suction port (not shown) to be connected with the pump41and configured such that the fuel passed through the filter member423can be sucked by the pump41.

An outer periphery of the upper base421is of a similar shape but smaller than an outer periphery of the lower base422. A clearance space is formed between the upper base421and the lower base422when the filter member423is not interleaved. The clearance space can serve to introduce fuel into the base portion42. In this embodiment, thus, instead of interleaving, one surface of the upper base421is arranged so as to be covered by the filter member423. As a result, the fuel entering from the unoccupied clearance into the base portion42also reaches the pump41through the filter member423.

A pressure control valve43is attached to the pump unit4that is used for controlling liquid feed pressure of the fuel. The pressure control valve43is attached to a valve supporting portion (not shown) extending from the pump41. The fuel with adjusted pressure by the pressure control valve43is fed to the internal combustion engine, for example, via a hose51and the outlet port23.

As shown inFIG. 1, the connecting portion3aand the pump unit4are connected by the connecting shaft45which is provided as part of the pump unit4, and is inserted into the connecting hole31awhich is provided at the connecting portion3a. Consequently, referring to the directional arrows shown inFIG. 1andFIG. 2, the connecting portion3aand the pump unit4are connected via the connecting shaft45so as to be rotatably movable relative to each other.

Referring toFIGS. 1 and 3, an engagement portion49is provided at the lower base422of the base portion42. The engagement portion49can engage with the lower end of connecting portion3asuch that the pump unit4can be maintained in an abutted state where it abuts the bottom surface73of the fuel tank7when the connecting portion3athrough its lower end applies a pressing force to the engagement portion49.

Referring toFIGS. 1 and 3, the engagement portion49is configured to have a substantially flat plate shape in a plane parallel to the XY plane, with a bottom surface arranged on the same plane as the leading ends of the leg portions4222which are provided extending downwards from the lower base422. A top surface, which can abut the lower end of the connecting portion3a, is formed on the vertically opposite side of said bottom surface. The connecting portion3ais maintained abutting the engagement portion's top surface by shortening the distance between the cover member2and the pump unit4through pressing the cover member2, which results on downwards force being applied to connecting portion3a. At this time, a spring53arranged between the cover member2and a part of the connecting portion3ais compressed and a restoring force in a downwards direction of the spring53for attempting to return into its original shape is transmitted to the bottom surface73of the fuel tank7via the lower end of the connecting portion3aand then the engagement portion49. Consequently, in this manner, the engagement portion49is maintained in a pressed state against the bottom surface73of the fuel tank7.

The connecting portion3ashown inFIGS. 1 to 3is telescopic, and can be extended and retracted. The connecting portion3aincludes rod members35attached to the cover member2and a joint portion36which is movable along the length of rod members35. The rod members35extend in a direction orthogonal to the plane in which the set plate portion21radially extends, parallel to the XY plane. Further, as mentioned, the spring53that can exert elastic force, is arranged between the joint portion36and the cover member2. The spring53biases the cover member2to move away from the pump unit4whenever the cover member2and the pump unit4mutually approach closer than a predetermined distance. In this manner, the spring member53is compressed whenever the cover member2is moved towards the bottom surface portion73of the fuel tank7from an existing state in which the bottom surface of the pump unit4is already touching the bottom surface portion73of the fuel tank7. As long as this compressed state of the spring53is maintained, the corresponding pressed state of the pump unit4against the bottom surface73will also be maintained. In particular, biasing force from the compression of the spring53is transmitted downward from the connecting portion3ato a connected engagement portion49which is provided at the pump unit4to press the engagement portion49against the bottom surface73of the fuel tank7.

Referring toFIG. 1, the connecting hole31ais configured to have a vertically elongated hole that allows the connecting shaft45and the rotation axis it comprises in the direction orthogonal to the XZ plane to be relatively movable in upward and downward directions. More specifically, the connecting hole31ais formed such that the connecting shaft45can move vertically in the XZ plane, in a direction substantially orthogonal to a plane in which the set plate portion21radially extends (a plane parallel to the XY plane extending in forward and backward as well as leftward and right ward directions). The connecting hole31aincludes a slide hole portion311in which the connecting shaft45can freely slide vertically. The connecting shaft45has a main body portion inserted in the slide hole portion311and a leading end at its leftmost terminal portion having a larger radius than that of the main body portion. The connecting hole31ahas a connecting shaft insertion portion312to allow the leading end of the connecting shaft45to be inserted. The slide hole portion311and the connecting shaft insertion portion312of the connecting hole31aare continuously formed. The slide hole portion311of the connecting hole31ais a vertically elongated hole, which is elongated in the upward and downward directions where the slide hole portion311allows the movement of the connecting shaft45in said upward and downward directions.

An engagement piece313is provided within the connecting shaft insertion portion312. The engagement piece313is elastically deformed when pressed from one direction but is not deformed when pressed from a direction orthogonal to the said direction. Therefore, it can prevent the connecting shaft45, when connecting shaft45is inserted into the connecting hole31a, from easily being removed from the connecting hole31a.

The connecting shaft45can move in upward and downward directions since through the vertically elongated hole shape of the connecting hole31a. Therefore, it is possible to maintain the lower end of the connecting portion3aand the engagement portion49in an abutted state relative to each other even when the pump unit4is rotated about the leftward-to-rightward rotary axis of shaft45resulting in the pump unit being inclined, as indicated by the directional arrows shown inFIG. 1. Further, the lower end of the connecting portion3aand the engagement portion49can be maintained in an abutted state not only if the connecting hole31bconfigured to have an elongated shape, but they can also abut each other if an end of the connecting portion3bis configured in a circular arc shape as shown inFIG. 7. However, if the connecting hole31bis configured to have an elongated shape, according to the configurations in embodiments shown inFIGS. 1 to 6, the flexibility of the shape at the lower end of the connecting portion3ais then increased, because with the elongated hole31b, it is then not necessary to configure the end of the connecting portion3ato have a circular arc shape.

As shown inFIGS. 3 and 4, the terminal portion positioned at a lower end of the connecting portion3ahas a surface3aaconfigured to be substantially parallel to the set plate portion21. The surface is configured as a flat surface parallel to the XY plane, formed in a substantially rectangular shape. The rectangular surface3aaabuts the top surface of the engagement portion49when the upper surface71and the bottom surface73of the fuel tank7are parallel. Curved surfaces3abare formed extending from both the forward and backward ends of the rectangular surface3aa. The curved surfaces3abare configured in an arcuate shape as seen from a side view in the XZ plane. The curved surfaces3abnormally do not abut the engagement portion49, e.g. when the upper surface71and the bottom surface73of the fuel tank are parallel, and3aaabuts the top surface of the engagement portion49. However, as shown inFIGS. 5 and 6, the curved surfaces3abmay abut the engagement portion49when the bottom surface73of the fuel tank7is deformed to be inclined.

As shown inFIGS. 3 and 4, an abutting area of the top surface of the engagement portion49and the lower terminal end of the connecting portion3acan be ensured to be relatively large when the surface3aaabutting the engagement portion49is a rectangular surface. As a result, the pump unit4can be firmly abutted to the bottom surface73of the fuel tank7when the fuel tank7is in a normal state i.e., not deformed.

An example of how the fuel supply device1behaves when the bottom surface73of the fuel tank7is deformed will be explained as follows. The fuel supply device1is usually maintained in a state attached to the fuel tank7. The shape of the fuel tank7can be deformed due to the environment of its use, including impact with other vehicles or property, accidents, etc. Namely, such causes for the deformation of the fuel tank7are most likely to occur after the fuel supply device1is attached to the fuel tank7, when the car is in operation, as opposed to other times. Hereinafter, a behavior of the fuel supply device1in this case will be briefly described.

According to the fuel supply device1as shown inFIGS. 3 and 4, in an ordinary circumstance, the pump unit4is pressed against the bottom surface73of the fuel tank7. This is caused by the downwards biasing force exerted by the spring53which is positioned between the cover member2and the joint portion36. When the tank is then deformed, because the bottom surface is now altered from the ordinary circumstance, the pump unit4rotates about the connecting shaft45since the biasing force is still being applied from the spring53to the pump unit4via engagement portion49when the bottom surface73of the fuel tank7is deformed as shown inFIG. 5. This may be achieved when the connecting shaft45moves from the position shown by a two-dot line inFIG. 6to a position shown by a solid line.

As long as the deformation of the bottom surface73is caused within a predetermined range, the pump unit4continuously receives the biasing force from the spring53. Therefore, with this continuous application of downwards biasing force, and the above described rotation, the pump unit4is maintained in an abutted state against the bottom surface73of the fuel tank7. The predetermined range may be determined by an amount of movement of the connecting shaft45relative to the connecting hole31a. Specifically, it may be determined by a longitudinal vertical length of a slide hole portion311of the connecting hole31a. Therefore, with the abutment of the pump unit4to the bottom surface of the fuel tank7within the predetermined range of deformation, fuel supply device1may suck the fuel at the bottom of the fuel tank7through the suction port of the base portion42and to the pump41of the pump unit4, and thus the fuel can be efficiently used even when the bottom surface73of the fuel tank7is deformed.

An embodiment shown inFIG. 7is described as follows. As in the earlier embodiment, in the embodiment shown inFIG. 7, the pump unit4provided at the fuel supply device1can be maintained in an abutted state to the bottom surface73of the fuel tank7even when the bottom surface73of the fuel tank7is deformed to be inclined. According to the embodiment shown inFIGS. 1 to 6, this objective is achieved by the formation of the connecting hole31aas an elongated hole. In contrast, according to the embodiment ofFIG. 7, this objective can be achieved by configuring the lower terminal end of the connecting portion3bto be of a specific shape. Therefore, a major difference between the embodiment ofFIG. 7and the prior embodiment as shown inFIGS. 1 to 6is the configuration of the shape of the lower end of connecting portion3bas well as the configuration of the connecting hole. Hereinafter, this difference will be mainly described.

The connecting hole31aof the prior embodiment shown inFIG. 4is an elongated hole, while the connecting hole31bof the embodiment shown inFIG. 7is not an elongated hole. Therefore, unlike the prior embodiment, inFIG. 7, the connecting shaft45is substantially vertically immobile upwards or downwards relative to the connecting hole31b. The lower terminal end of the connecting portion3b, which abuts the engagement portion49, has a curved surface3badirectly below, and surrounding, the connecting shaft45. Namely, the curved surface3bamay have a circular arc shape as seen from a side view where it is concentric with the center of the connecting hole31b. More specifically, the lower terminal end of the connecting portion3bis formed in a semicircular shape resembling the lower half of a circle, about the center of the connecting hole31bas seen from a side view in the XL plane. If this configuration is seen in view of the relation of the lower terminal end of the connecting portion3bwith respect to the connecting shaft45, a central axis of the semicircular portion which forms the lower terminal end of the connecting portion3b, around which rotation may occur, substantially corresponds to an axial center R of the connecting shaft45.

According to the fuel supply device1shown inFIG. 7, a relative angle of the abutment of the engagement portion49of the pump unit4and the lower terminal end of the connecting portion3b, relative to the horizontal, may be changed while maintaining the abutted state. Furthermore, the range of followability of the pump unit4, in which it may continue to receive biasing force from53, in response to the deformation of the fuel tank7, is increased because the rotation of the pump unit4in both directions is allowed from the state shown inFIG. 7as denoted by the directional arrows (i.e., from the position where the set plate portion21and the pump unit4are arranged substantially parallel, with an angle of abutment of the engagement portion49of the pump unit4and the lower terminal end of the connecting portion3bof about 0 degrees relative to the horizontal).

While the embodiments of disclosure have been described with reference to specific configurations, it will be apparent to those skilled in the art that many alternatives, modifications and variations may be made without departing from the scope of the present disclosure. Accordingly, embodiments of the present disclosure are intended to embrace all such alternatives, modifications and variations that may fall within the spirit and scope of the appended claims. Embodiments of the present disclosure should not be limited to the representative configurations, but may be modified, for example, as described below.

For example, the elongated hole (connecting hole31a), instead of a linear vertically elongated hole as disclosed above, may have a linear shape as well as a bent shape such as a substantially L-shape, which is bent in the middle. The width of the elongated hole (connecting hole31a) may be changed in the middle.

A circular arc portion (curved surface3ab) shown inFIG. 4is not necessarily provided at both ends of a pressing portion (the leading end comprising the lower terminal end of the connecting portion3a). It may also be provided at only one of the ends, or may not be provided at all. If the circular arc portion is not provided at all, one part or an entire surface of the engagement portion49abutted to the connecting portion3amay be configured in a circular arc shape as seen from a side view in the XZ plane.

The filter member is not necessarily arranged at the base portion. Therefore, it is also possible to configure the base portion without the filter member. In this case, the filter member may be arranged at any other portion than the base portion. In a further alteration, if the fuel to be sucked by the pump is maintained in a clean state, the filter member does not have to be present in the fuel supply device at all.

Moreover, as per the vehicle, the disclosure is not limited in scope to automobiles. It may also be used in a vehicle that flies in the air (e.g. an airplane or a helicopter), or that moves over the sea or in the sea (e.g. a ship or a submarine).

According to the embodiment inFIG. 3, the connecting shaft45is formed as part of the pump unit4and the connecting hole31ais formed as part of the connecting portion3a. Alternatively, the pump unit4may also be connected relatively movable with respect to the connecting portion3aof the pump unit4by having the connecting shaft formed as part of the connecting portion3and the connecting hole formed as part of the pump unit so that the connecting shaft is inserted into the connecting hole.