JP2003293885A - In-tank fuel filter - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To easily and efficiently assemble a modularized in-tank filter. <P>SOLUTION: In this in-tank fuel filter, a pump 30 and a filter unit are assembled and modularized as an integrated matter, and fixed and mounted in a fuel tank. The modularization is performed by engaging the integrated member obtained by assembling the pump 30 and the filter unit, with a set plate 150 integrally mounted on the fuel tank, directly or through a housing member covering the integrated member, and mounting a cover 160 for holding the pump 30 on the integrated member, in a state of being engaged with the integrated member 117, 161. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fuel filter for removing foreign matters from fuel delivered from a fuel tank by a fuel pump. In particular, the present invention relates to an in-tank type filter installed and used in a fuel tank. More specifically, it relates to an in-tank type filter improved so as not to be easily charged. In this specification, the fuel pump is simply called a pump, the fuel filter is simply called a filter, the fuel tank is simply called a tank, and the filter used in the tank is called an in-tank type filter.

[0002]

2. Description of the Related Art An example of an in-tank type filter is German Patent Application P4242422.6 (Japanese Patent Laid-Open No. 6-213091).
(Corresponding to the publication). In this technique, a filter having a substantially cylindrical shape is attached to the outer periphery of a pump having a substantially cylindrical shape to form a modular filter. This modular filter is used by being installed in the tank. The conventional modularized in-tank filter is very effective in simplifying the process of mounting the pump and the filter unit in the tank. However, no special consideration is given to the fact that the filter and the fuel are charged. When the fuel passes through the filter member and the foreign matter is concentrated, the fuel and the filter member rub against each other. Due to the friction at this time, the fuel is positively charged and the filter member is negatively charged. When the fuel is charged, the fuel pipe is charged. The fuel pipe is electrically insulated from the vehicle body or the like because it is usually fixed to the vehicle body or the like via an insulating elastic body such as a rubber bush to protect it from vibrations and the like. When the fuel pipe is charged, a discharge may occur between the fuel pipe and a metal body part or the like adjacent to the fuel pipe, and the discharge may damage the wall of the fuel pipe. As a result of the fact that repeated discharges have actually occurred, there have been cases where the wall of the fuel pipe was severely damaged. Further, when the filter member is charged and the charged electric charge is accumulated to increase the charging potential, the service life of the filter may be shortened or spark discharge may occur. If the filter cover forming the surface of the filter is made of a non-conductive material such as resin,
Although the possibility of spark discharge is low, the deterioration of the resin progresses due to charging, and the life is shortened. If the filter cover is made of a conductive material such as metal, the reduction in life is not a serious problem, but spark discharge is likely to occur. In this way, the electrostatic charge generated by filtration is
It causes very serious problems in both the filter and the fuel line. Nevertheless, the conventional filter does not give special consideration to charging. For example, in a traditional filter,
The fuel is filtered by causing the fuel to flow axially rather than radially in the cylindrical filter member. The amount of charge on the fuel or the filter member when the fuel passes through the filter member and is filtered by foreign matter is affected not only by the total amount of passage of the fuel but also by the passage speed and the time required for passage. The faster the passage speed, the easier the charging becomes, and the longer the passage time, the easier the charging becomes. When filtering fuel with a cylindrical filter member, passing the fuel in the axial direction makes the fuel passing speed faster and the contact distance between the fuel and the filter member longer than when passing the fuel in the radial direction. Takes longer. On the other hand, when the fuel is flowed in the radial direction, the passage speed of the fuel becomes slower, the contact distance between the fuel and the filter member becomes shorter, and the time required for passage becomes shorter. As a result, the amount of charge generated in the filter member that allows the fuel to flow in the radial direction is significantly smaller than the amount of charge that occurs in the filter member that allows the fuel to flow in the axial direction.
Nevertheless, the conventional in-tank filter adopts a method of passing the fuel by flowing it in the axial direction, and even the awareness of the problem of making it difficult for the filter and the fuel to be electrically charged is not recognized. The most common way to prevent the filter from being charged is to discharge the charged charge. It is generally considered that if the filter cover that forms the surface of the filter is molded with resin, the charged electric charge cannot be discharged.Therefore, in this method, the filter cover is made of metal, and the metal cover and the ground, etc. By connecting the wires, the electric charge charged on the filter cover is discharged to the vehicle body or the like. If the filter cover is made of metal, the manufacturing cost is high and the shape of the cover cannot be freely designed. Therefore, a method of molding the filter cover with a conductive resin can be considered. This is disclosed in WO92 / 04097 (corresponding to Japanese Patent Publication No. 6-213091). This publication describes a technique in which a filter cover is formed of a conductive resin and a ground wire is connected between the cover and the vehicle body to discharge the electric charge charged in the filter cover.

[0003]

[Patent Document 1] JP-A-6-213091

[0004]

A method in which a filter cover is made of a conductive material such as a metal or a conductive resin and an earth wire is connected to the cover to cope with the electric charge accumulated in the filter is as follows. It has some drawbacks. First, even though the filter is discharged, the fuel is not discharged, and no measure is taken against charging the fuel pipe. As described above, the fuel pipe is usually attached to the vehicle body or the like via an insulating member such as a rubber bush, and when this fuel pipe is charged, spark discharge is generated between the fuel pipe and the vehicle body and the fuel pipe is damaged. It may cause serious problems. Even if the filter cover is made of a conductive material and the ground wire is connected, no countermeasure is taken against this problem. Also, WO92
/ 04097, when the filter cover is made of a conductive resin, its volume resistivity cannot be made sufficiently low, and even if the ground wire is attached, the charging potential is still zero. You can't.
In particular, it is difficult to reduce the volume resistivity evenly,
Areas with high local resistance tend to remain. For this,
A locally high potential portion is likely to occur, and there is a possibility that spark discharge may occur when the locally high potential portion approaches the tank during replacement of the filter. Further, since the discharge current concentrates in the conductive resin near the mounting portion of the ground wire, the problem that the resin is likely to deteriorate cannot be solved. If the filter cover is made of metal, most of the above problems are solved, but the metal does not solve the serious problem that the manufacturing cost of the filter cover increases and the degree of freedom of the shape is limited. . Further, the problem that the fuel or the fuel pipe is charged cannot be solved.

An object of the present invention is to realize a new in-tank type filter which can effectively deal with the troublesome problem of electrification which occurs in a conventional filter. Another object of the present invention is that the charge potential generated in the filter is
The purpose is to prevent the resin filter cover from becoming so high as to shorten its life. Still another object of the present invention is to enable the filter cover to be constructed without using a special resin such as a conductive resin. Yet another object of the present invention is to eliminate the need to attach a ground wire to the filter cover.

[0006]

According to one aspect of the present invention, a cover of a substantially cylindrical filter member installed in a tank is formed of a non-conductive resin, and the substantially cylindrical filter member is provided. The filter member is of a type that allows fuel to flow in a radial direction to be filtered. It is possible to use a filter member of a type that filters fuel by flowing it in a radial direction, and to form the cover of the filter member with a non-conductive resin.
It is disclosed in the above-mentioned Patent Document 1. However, this technique uses this filter outside the fuel tank. Therefore, in this publication, it is pointed out that the filter cover made of resin is destroyed by charging in this type of filter, and in order to prevent this, it is proposed to form the filter cover with a conductive resin. There is. However, as a result of various experiments conducted by the present inventor, even when the filter cover is formed of a non-conductive resin, when the filter cover is used in the tank, the filter member is less likely to be charged by flowing the fuel in the radial direction. By doing so, it was confirmed that it is possible to prevent the non-conductive resin cover from rapidly deteriorating due to being charged, and to obtain a normally required life. With such confirmation, the present inventor succeeded for the first time in practical application of an in-tank filter having a non-conductive resin cover. In the case of the filter of this aspect, the charging potential is not zero because the filter cover is not grounded on the vehicle body or the like. However, since the filter cover is made of a non-conductive material having a large volume resistance, abrupt movement of charged charges is prohibited, and even if the resin filter cover comes close to metal parts having different potentials, No spark discharge occurs.

According to another aspect of the present invention, when a filter having a substantially cylindrical shape is assembled to the outer periphery of a pump having a substantially cylindrical shape to form a filter, the cover forming the surface of the filter is made non-conductive. Made of the following materials, and
The cylindrical filter member is a filter member of a type in which fuel is radially passed to filter foreign matters. With this type of filter member, the amount of charge can be kept low,
When this filter member is covered with a non-conductive cover and placed in the tank, when the cover is exposed from the remaining fuel in the tank and charging becomes a problem, corona discharge is generated from the exposed cover surface. Occur. This corona discharge has low energy and does not cause any particular problem. Due to this corona discharge, the amount of electric charges charged on the cover surface can be suppressed to a level that does not reduce the life of the resin cover. Further, since the filter cover is formed of a non-conductive member having a large volume resistance, abrupt movement of charges is prohibited, and spark discharge does not occur even when it approaches metal parts having different potentials.

In another aspect of the present invention, the filter member is doubly covered. In this specification, the inner cover is called a case and the outer cover is called a housing. If this filter is installed in the tank after the case and housing are covered double, and at least the outer side (that is, the housing) is made non-conductive, the amount of electric charge charged on the surface of the filter will not decrease the life of the housing. It can be kept low. In still another aspect of the present invention, the return fuel flows along the filter to discharge the electric charge generated in the filter and reduce the noise generated when the return fuel drops to the remaining fuel in the tank. .

The present invention will be understood more clearly with reference to the description of the best mode described below.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION The best mode for carrying out the present invention will be described below. [First Embodiment] First, the filter member 7 will be described. As shown in FIG. 7 (a), this filter member is formed by folding a sheet-shaped filter material 7D along a large number of parallel lines and bending it into a substantially C-shape. A substantially C-shaped upper end plate 7A is fixed to the upper surface of the filter material 7D, a substantially C-shaped lower end plate 7C is fixed to the lower surface, and a pair of side end plates 7B and 7B are fixed to the pair of side ends. Has been done. There is no gap between the filter material 7D and each of the end plates 7A, 7B, 7B, 7C, and they are fixed in a liquid-tight manner. Each end plate 7A, 7B, 7
An elastic shield member 8 (8
A, 8B, 8B, 8C) are adhered. These shield members 8 come into close contact with the inner wall of the case 2 when the filter member 7 is housed in the case 2 described later. In addition,
As the filter member 7, various filter members such as a honeycomb structure filter member and a vortex structure filter member can be used in addition to the filter member 7D obtained by bending a filter medium. Alternatively, the shield member 20 shown in FIG. 7B can be used.

Next, the case 2 in which the filter member 7 is housed
Will be described. 1 to 3 show a state where the filter member 7 is housed in the case 2, and the whole thereof is called a filter unit 1. 1 is a plan view of a filter unit 1 of the first embodiment, FIG. 2 is a sectional view taken along the line A-C of FIG. 1, and FIG. 3 is a sectional view taken along the line B-C of FIG.

As shown in FIGS. 1 to 3, the case 2 of the filter unit 1 is composed of a case body 2A and a case cap 2B, both of which are made of conductive resin or non-conductive resin. The case main body 2A is a bottomed double cylinder composed of an inner peripheral wall 3, an outer peripheral wall 4, and a substantially annular bottom wall 3A connecting the peripheral walls 3 and 4. As shown in FIG. 1, the case 2 has a substantially D-shaped cross section. That is, as well shown in FIG.
The outer peripheral wall 4 is cut in a part in the circumferential direction, and the circumferential end 4A of the cut outer peripheral wall 4 and the inner peripheral wall 3 are connected by a side wall 3B. The case 2 and the filter unit 1 are constructed by inserting the filter member 7 into the space having an approximately C-shaped cross section between the inner peripheral wall 3 and the outer peripheral wall 4 and then closing the upper opening of the case main body 2A with the case cap 2B. It At this time, the substantially C-shaped shield member 8A of the filter member 7 strongly contacts the case cap 2B to prevent fuel from passing through the gap between the filter member 7 and the case cap 2B. Further, the substantially C-shaped shield member 8C strongly contacts the bottom plate 3A to prevent fuel from passing through the gap between the filter member 7 and the bottom plate 3A. Further, the substantially linear shield members 8B, 8B strongly abut against the side walls 3B, 3B to prevent fuel from passing through the gap between the filter member 7 and the side wall 3B. That is, four rounds of the filter member 7 are strongly pressed against the inner surface of the case 2, and the space between the inner circumferential wall 3 and the outer circumferential wall 4 having a substantially C-shaped cross section is liquid-tightly partitioned by the filter member 7.
When the filter member 7 or the case 2 itself has a sealing action, the space outside the filter member 7 and the space inside can be liquid-tightly partitioned without using the shield member 8.

As best shown in FIGS. 2 and 3, the case cap 2B is provided with an inflow side mounting hole 11. The inflow side attachment hole 11 communicates with the fuel inflow chamber 9 (referred to as a space surrounded by the filter member 7 and the outer peripheral wall 4) via the passage 12 and the fuel inflow port 13. Further, the case cap 2B is provided with an outflow side attachment hole 15 as well shown in FIG. The outflow-side mounting hole 15 is connected to the fuel outflow chamber 10 (filter member 7) via the fuel outflow port 14.
And the space surrounded by the inner peripheral wall 3).
This is well shown in FIG. 1 in order to form a large fuel inlet 13 on the outer peripheral side of the filter member 7 (more accurately, the shield member 8) and a large fuel outlet 14 on the inner peripheral side. Thus, the approximately C-shaped shield member 8 is fixed at a position offset from the center of curvature of the filter member 7. On the right side of FIG. 1, the outer peripheral side is largely secured by the inner side of the shield member 8, and on the left side, the inner peripheral side is largely secured by the outer side of the shield member 8. Therefore, the opening areas of both the fuel inlet 13 and the fuel outlet 14 can be sufficiently secured.

As best shown in FIGS. 1 and 2, a cylinder 16 is formed on the upper surface of the case cap 2B for receiving return fuel from the engine or the pressure regulator. The bottom of the cylinder 16 is closed by the case cap 2B, and instead, a plurality of openings 17 are formed in the side portion. The fuel flowing into the cylinder 16 flows out from the plurality of openings 17, and radially flows out from the cylinder 16 on the surface of the case cap 2B. The case cap 2B has an opening 2C formed in the upper portion of the pump housing space 5, and when the remaining fuel in the tank is small and the opening 2C projects upward from the liquid level of the remaining fuel, the case cap 2B is formed. A part of the fuel flowing on the surface of the above flows into the opening 2C. Case body 2A
The inner space of the inner peripheral wall 3 is a space 5 for accommodating the pump 30, and as shown well in FIG. 9, the pump 30 extends from the lower opening 6 of the case body 2A to the pump storage space 5. Inserted in. The pump 30 is inserted into the pump housing space 5, and the discharge port 31 of the pump 30 is connected to the inlet side mounting hole 11 of the case 2 via the spacer 32 and the bush 33.

A small gap is formed between the pump 30 and the inner peripheral wall 3 so that the fuel remaining in the tank is small and the module and the cylinder 16 are opened even when the module is exposed above the liquid level of the remaining fuel. 17 and the return fuel flowing through the upper surface of the case cap 2B and the opening 2C of the case cap 2B,
It flows into the gap between the pump 30 and the inner peripheral wall 3, and the return fuel fills the gap. Further, most of the fuel flowing on the surface of the case cap 2B flows along the outer peripheral wall of the case body 2A. For this reason, the surface of the case 2 is always covered with fuel to facilitate discharge, and after the flow velocity of the returning fuel is sufficiently reduced, the case 2 has a function of dropping to the liquid surface of the remaining fuel. can get. For this reason, the falling noise of the return fuel is suppressed, the charging of the case 2 is easily discharged, and the charging potential is suppressed. The integrated product in which the pump 30 and the filter unit 1 are assembled is further housed in the housing. The integrated product housed in this housing is simply called a filter. The housing is composed of a housing body 40 and a housing cap 50, both of which are made of non-conductive resin. in this case,
The housings 40 and 50 are covers that form the surface of the filter.

The housing body 40 has a cylindrical shape having an opening 40A on the bottom surface and is open at the upper side, and an integrated product in which the pump 30 and the filter unit 1 are assembled is inserted from the upper opening. Reference numeral 41 in the figure denotes a support member formed of a non-conductive material such as a non-conductive resin.
The housing body 40 has a D-shaped cross section according to the outer shape of the case 2. When the integrated body in which the pump 30 and the filter unit 1 are assembled is inserted into the housing body 40, the fuel suction port of the pump 30 formed at the lower end of the pump 30 projects from the opening 40A, and the first bag-shaped portion is formed therein. The next filter 34 is attached. A return pipe mounting portion 56 for returning fuel and a feed pipe mounting portion 58 for sending fuel out of the tank are fixed to the housing cap 50 by penetrating the housing cap 50. The opening 54 on the lower side of the cap of the feed pipe mounting portion 58 is formed at a position corresponding to the outflow side mounting hole 15 of FIG. 1, and the opening 57 on the lower side of the cap of the return pipe mounting portion 56 is formed on the tube 16 of FIG. It is formed at the corresponding position.

When the housing cap 50 is fixed to the upper end 42 of the housing body 40, the outflow side mounting hole 15 of the case 2 is connected to the opening 54 of the feed pipe mounting portion 58 through the fuel supply pipe 60 and the O ring 61. . Further, the opening 57 of the return pipe attachment portion 56 faces the cylinder 16 formed in the case 2. The opening 57 and the tube 16 may be connected by a hose. Reference numeral 52 denotes a cushion, which positions the integrated body in which the pump 30 and the filter unit 1 are assembled and the housing (the housing body 40 and the housing cap 50). Reference numeral 53 is a power supply connector, and the pump 30 is connected to the connector 53.
Connect the power terminal of. Integrated product in which the pump 30 and the filter unit 1 are assembled and the housing (40, 50)
Are integrated to form a filter. This filter is inserted and fixed in a tank (not shown). The surface of this filter is a non-conductive resin cover (housing 4
0,50). The housing cap 50 of the first embodiment corresponds to the set plate 150 (see FIG. 18) in the third embodiment described later.

Next, the operation of this filter will be described. The pump 30 sucks the fuel in the tank through the primary filter 34, and from the discharge port 31 to the passage 12 and the fuel inlet 13.
The fuel is fed into the fuel inflow chamber 9 via. Fuel inflow chamber 9
The fuel sent in passes through the filter material 7D of the filter member 7 in the radial direction and is sent to the fuel outflow chamber 10, where it is filtered. The filtered fuel is the fuel outlet 14,
It is sent out to the feed pipe attachment portion 58 via the fuel supply vip 60 and the passage 55. A feed pipe (not shown) is connected to the feed pipe attachment portion 58, and the other end side of the feed pipe is connected to the fuel injection device. Also,
A pressure regulator (not shown) is connected to the feed pipe (not shown), and releases the fuel when the fuel pressure in the feed pipe exceeds a predetermined value. A return pipe is connected to this fuel escape port. The fuel discharged to the return pipe is guided from the return pipe mounting portion 56 into the inside of the cylinder 16, and the plurality of openings 1
7 flows out onto the surface of the case cap 2B. Part of the fuel that has flowed out flows down through the gap between the pump 30 and the inner peripheral wall 3 of the case 2. Most of the return fuel flows down through the gap between the outer peripheral wall 4 of the case 2 and the housing body 40. That is, the inner peripheral wall 3 and the outer peripheral wall 4 of the case 2 and the inner surface of the housing main body 40 are always kept in contact with the fuel.

The fuel returned from the return pipe flows down along the outer circumference of the pump 30 and the outer circumference of the case body 2A. Since these flow passages have a long circumference, the flow passage has a large cross-sectional area, and the fuel slowly flows in a thin film around the pump 30 and the case body 2A. For this reason, the sound generated with the return of fuel is suppressed. When the fuel passes through the filter member 7, the filter member 7, the case 2 and the housings 40 and 50 are charged with electric charges. The amount of fuel remaining in the tank is large and the housing 4
When the contact area between 0 and 50 and the fuel is large, it is difficult for electric charges to accumulate on the surfaces of the housings 40 and 50. However,
When the amount of fuel remaining in the tank is reduced and the contact area between the housing and the fuel is reduced, electric charges tend to accumulate on the surface of the housing. A technique in consideration of charging generated on the filter cover is disclosed in WO92 / 04097. In this technology, if the filter case is made of non-conductive resin, it will be destroyed by electrostatic charge.To solve this problem, a cover is made of conductive resin that is a mixture of conductive particles and resin. Ensure a conductive path between and. As a result of various researches conducted by the present inventor, it was discovered that this technique could be applied to the in-tank type module of the present invention. First of all, when the filter cover is made of a conductive resin, it is difficult to form the entire surface with uniform conductive characteristics, and the charging potential on the surface of the filter cover tends to become uneven depending on the location. Found. If the charging potential differs from place to place and the filter cover is conductive, there is a possibility that spark discharge will occur. Further, it was found that the discharge current is concentrated near the attachment portion of the ground wire, so that the deterioration of the conductive resin rapidly progresses. Furthermore, WO92 / 04097
In the case where the filter is used near the engine outside the tank, the charging of the fuel or the fuel piping is not a particular problem as disclosed in, whereas when the filter is installed inside the tank, In addition, electrification of the fuel pipe has a great influence on the life of the fuel pipe, and no measure can be taken against the electrification of the fuel or the fuel pipe only by discharging the electric charge accumulated on the filter cover. Under such circumstances, it has been found that in the case of the in-tank type filter, the measures shown in WO92 / 04097 are not effective measures. On the other hand, it was found that the filter used outside the tank shown in WO92 / 04097 and the filter used inside the tank handled by the present invention have completely different discharge environments. When used in a tank, the filter is covered with fuel vapor even if the amount of fuel in the tank is low and the filter is exposed from the liquid surface of the fuel, and therefore the filter is placed in the atmosphere. It was found that the discharge characteristics are different from those of the case. Secondly, it was found that the charge potential of the filter cover can be considerably lowered by utilizing the return fuel to accelerate the discharge. Due to such circumstances,
In the case of an in-tank type filter, if a filter member that is difficult to be charged is adopted (even if the surface of the filter is made non-conductive, it will not be destroyed. The charge potential of the filter does not rise to such a level that the discharge is continuously generated and the life of the resin filter cover is reduced, and even if the surface of the filter contacts or approaches the tank during maintenance, etc. Since the volume resistance of the filter surface is large, it was confirmed that the movement of charges is suppressed and the spark discharge is effectively suppressed. As shown in Fig. 6, the fuel is passed through in the radial direction, and the outermost surface of the filter is formed of a non-conductive member. When used in a tank, the charging potential generated on the filter member is suppressed to a low level in the first place, and corona discharge is generated from the surface of the filter to suppress the surface potential of the filter to a low level. It has been confirmed that spark discharge does not occur easily because it is made of a material that has high volume resistance and is highly conductive. Even when the surface comes into contact with a tank or the like, the electric charge accumulated on the surface of the filter (in this case, the housing body 40) does not rapidly flow, and the spark discharge is effectively suppressed.

FIG. 20 shows the relationship between the volume resistivity of the member forming the surface of the filter and the discharge energy.
When the volume resistivity is 108 to 1010 ohm · cm, the discharge energy is suppressed low, and at the same time, the charging potential is also suppressed low. The range of 108 to 1010 ohm · cm is a range in which both are balanced, and the material of the filter case is preferably selected from those having a volume resistivity within the above range. Further, in the case of this embodiment, the return fuel is caused to flow along the surface of the case 2 to prevent excessive charge from being accumulated on the surface of the case 2. In this embodiment, the filter member 7 is housed in the case 2, and the case 2 is housed in the housings 40 and 50. That is, the filter member 7 is doubly covered. In this case, the principle of the invention works if the outer cover (in this case the housings 40, 50) is non-conductive, and the inner cover (in this case case 2) is conductive or non-conductive. Has been confirmed to be good. In any case, continuous corona discharge can be obtained from the outer housing (40, 50), and the deterioration of the filter cover can be effectively suppressed.

Further, in this embodiment, the return fuel is caused to flow along the surfaces of the case 2 and the housings 40, 50 to reduce the charge accumulated on the surfaces of the case 2 and the housings 40, 50. The effect of reducing the charge by flowing this return fuel along the case or housing is that the amount of fuel remaining in the tank decreases, the contact area between the housing and the fuel in the tank decreases, and the charge on the filter surface discharges. It is effective when it becomes difficult to do. Since the return fuel is received by the cylinder 16 and flows through a wide range on the surface of the case cap 2B from the plurality of openings 17, the charging potential of the case 2 or the housing can be uniformly lowered over the entire surface. . In the case of a filter member having a substantially cylindrical shape, as shown in FIG. 6, in the case of a type in which fuel is flowed in the radial direction for filtration, the filtration area is the length in the circumferential direction multiplied by the height. . On the other hand, as shown in FIG. 19, the passage area in the case where the fuel is filtered by flowing the fuel in the axial direction is the circumferential length multiplied by the thickness of the filter medium. Of course, the former is usually much larger than the latter. Therefore, if the amount of filtered fuel per unit time is the same, the passage speed with the former filter is slower than the passage speed with the latter filter. FIG. 10 shows the relationship between the flow rate and the flow velocity. A shows the relationship when flowing in the axial direction, and A shows the relationship when flowing in the radial direction. Clearly, for the same flow rate, the axial flow rate is faster than the radial flow rate.

The charge amount (charge potential) generated in the filter when the fuel passes through the filter is affected by the fuel passage speed, and the faster the flow velocity, the higher the charge potential. Figure 1
1 shows the relationship between the flow velocity and the charging potential. The type (a) in which the flow velocity is in the axial direction has a high charging potential, and the type (a) in which the flow velocity is in the radial direction has a low charging potential. In practice, the charge potential developed on the filter is also affected by the time it takes for the fuel to pass through the filter. When flowing in the radial direction, the contact time between the fuel and the filter is short because the flow velocity of the fuel is slow but the thickness of the filter member is not so large. On the other hand, in the case of flowing in the axial direction, since the flow velocity has to pass through the height of the filter member at the earliest, the contact time between the fuel and the filter is long. From these things, by using the filter that flows in the radial direction, the amount of charge generated by the filter can be significantly reduced as compared with the case of using the filter that flows in the axial direction. The present invention arrives at such knowledge and the peculiarity of being used in a tank, and in the case of a filter used in a tank, a filter member having a low charge amount is used because the fuel flows in the radial direction. By covering with a conductive member,
It was created from the fact that it was confirmed that spark discharge could be prevented. In this embodiment, the filter member is doubly covered with the case and the housing. In the case of having a hanging double structure, at least the outer cover may be non-conductive. The inner cover may be conductive or non-conductive.
On the other hand, the cover that covers the filter member may have a single-layer structure. For example, the case 2 may be the outermost surface without using the housing. In this case, the case 2 needs to be non-conductive.

[Second Embodiment] Next, a second embodiment will be described with reference to FIGS. In the figure, a case 91 of the filter unit 90 is provided with a return passage 95 from the upper part of the case 91 along the outer peripheral surface. The return passage 95 has a circular cross section in the upper part of the case 91 so as to be opposed to or connectable with the discharge port of the return vapor or the pressure regulator, and the portion along the side surface of the case 91 has a semicircular cross section. There is. A discharge port 96 for discharging the return fuel into the fuel liquid is provided on the lower side wall of the return passage 95. The return passage 95 forms an additional fuel passage. The other configuration is the same as that of the filter unit 1 shown in FIGS.

In this embodiment, since the return fuel is guided into the fuel liquid by the return passage 95, the return sound can be further reduced. The cross-sectional shape of the return passage 95 can be various shapes other than circular and semicircular, and the number of return passages 95 may be plural.
Further, it is preferable that the return passage is integrally formed with the case by using synthetic resin or the like. 14 and 15, in addition to the pump 30 and the housings 40 and 70 in the filter unit 1 shown in FIGS.
FIG. 15 shows a filter in which 0 is also attached, and FIG.
FIG. 3 is a sectional view taken along line G-G of FIG. Similar to the filter shown in FIGS. 8 and 9, the fuel pump 30 is assembled to the case 2 of the filter unit 1, and the case 2 is housed in the housing body 40. Then, the housing cap 70 is attached to the housing body 40. At this time, the pressure regulator 180 is provided between the outflow side mounting hole 15 provided in the case 2 and the mounting hole 74 provided in the housing cap 70.
Is attached via the O-ring 61. The mounting hole 74 is connected to the feed pipe mounting portion 76 via the passage 75. The fuel outlet of the pressure regulator 180 faces the cylinder 16 for receiving the return fuel, or is connected to the cylinder 16. Similar to the module shown in FIGS. 8 and 9, the power supply connector 73 is connected to the power supply terminal of the fuel pump 30, and the cushion 52 and the primary filter 34 are attached.

The operation of the modularized filter shown in FIGS. 14 and 15 will be described. The fuel sucked by the fuel pump 30 has a discharge port 31, a passage 12, a fuel inlet port 13, a fuel inflow chamber 9, a filter member 7, and a fuel outflow chamber 1.
0, sent to the pressure regulator 180 via the fuel outlet 14. Pressure regulator 180
Discharges the fuel from the fuel discharge port to the return fuel receiving cylinder 16 when the pressure of the fuel in the passage 75 is equal to or higher than the set pressure. The fuel discharged to the cylinder 16 is returned to the fuel liquid along the surface of the case 2 through the plurality of openings 17 connected to the cylinder 16. As a result, the fuel pressure in the passage 75 is maintained at the set pressure. The fuel adjusted to the set pressure is
It is supplied to the fuel injection device via a feed pipe attachment portion 76 and a feed pipe (not shown).

FIG. 16 is a diagram in which accessories such as a sensor are assembled to the modularized filter. A mounting portion 80 is provided in a portion cut from the cylindrical shape of the housing 40 having a D-shaped cross section, and a groove 81 provided in the mounting portion 80 is provided in a sensor 85 such as a fuel gauge or a thermistor. The sensor 85 is attached to the housing 40 by engaging the engaging portion 86 provided.
Attach to. Since an accessory such as a sensor is attached to a portion cut from the cylindrical shape of the housing 40, the outer diameter of the filter to which the accessory is attached is equal to the housing 4
It is almost the same as the outer diameter of 0. Therefore, the modularized filter can be inserted through the circular mounting hole provided in the tank.

[Third Embodiment] In the above embodiments, the case is housed in the housing, and the housing is made of a non-conductive material. However, the case can also be used as the housing. This embodiment is shown in FIGS. 17 and 18.
Note that FIG. 17 shows a sectional view of the filter unit, and FIG. 18 shows a sectional view of a filter in which a pump and the like are assembled in the filter unit. In this case, the surface of the filter consists of the case. The case 102 of the filter unit 100 is made of a non-conductive material such as a non-conductive resin, and is provided with an inner peripheral wall 103 and an outer peripheral wall 104. Inner wall 10
A filter member 107 is attached by a shield member 108 between the outer peripheral wall 104 and the outer peripheral wall 104 so that a fuel outflow chamber and a fuel inflow chamber are formed on the inner peripheral side and the outer peripheral side. At the fuel outlet 114 communicating with the fuel outlet chamber,
The outflow side mounting hole 115 is provided, and the mounting hole 116 for mounting the pressure regulator is also provided. In addition, a hole 118 for mounting the set plate is provided in the upper part of the case 102, and the bump 3 is provided in the lower part.
An insertion opening 106 for inserting 0 and an engaging portion 117 for attaching the cover 160 are provided.

In order to construct a filter by assembling the pump 30 etc. to the filter unit 100 as described above, the case 1 is used.
The pump 30 is inserted from the insertion port 106 of No. 02, and the pressure regulator 180 is attached to the attachment hole 116. Next, by engaging the engaging portion 151 with the hole 118 provided in the case 102, the set plate 1
Attach 50 to case 102. At this time, the case 102
The fuel supply pipe 155 is attached between the outflow side mounting hole 115 provided in the mounting plate 150 and the mounting hole 154 provided in the set plate 150. Further, after the primary filter 34 is attached to the suction port of the fuel pump 30, the cover 160 is attached to the case 102 by engaging the engaging portion 117 provided on the case 102 with the hole 161. When such a filter unit 100 is used, electric charges are generated on the surface of the case 102 when the fuel passes through the filter unit 100. When the amount of fuel remaining in the tank becomes small, this electric charge easily accumulates on the surface of the case 102. However, corona discharge occurs between the surface of the case 102 and the vaporized fuel in the tank. Corona discharge is not a problem because the discharge energy is low. In this case, since the case 102 is made of a non-conductive material, the volume resistivity is higher than that of the conductive material, and the accumulated electric charge is not rapidly discharged. Further, even when the case 102 comes into contact with a tank or the like during work and the electric charge accumulated in the case 102 is discharged, the accumulated electric charge does not change abruptly. Therefore, there is no possibility that spark discharge will occur when the charge of the case 102 is discharged. In this embodiment, since the housing is unnecessary, the cost is low.

In the above embodiment, the fuel filter unit is assembled with the fuel pump or the like to form the filter, but the fuel filter unit may be installed alone in the tank and used. Although the case has a D-shaped cross section, it may have various shapes such as a circular shape and a C shape. Further, although the housing or the case is made of a non-conductive material and the return fuel is made to flow along the surface of the case, only one of them may be used. Also,
Although the structure in which the case is housed in the housing or the structure in which the case is also used as the housing has been described, the fuel filter is not limited to such a structure, and the spark discharge is most generated when the fuel filter comes into contact with the tank etc. Since it is easy, at least the outer peripheral portion that is likely to come into contact with the tank or the like may be formed of a non-conductive material.

[0030]

As described above, when the filter of the present invention is used, the surface of the filter is made of a non-conductive material, so that when the charged charge accumulated on the surface is discharged, the charge moves rapidly. There is nothing to do. With this, with a simple configuration, it is possible to prevent spark discharge or the like from being generated by the electric charge generated when the fuel passes through the fuel filter.

[Brief description of drawings]

FIG. 1 is a plan view of a filter unit of a first embodiment used in a filter of the present invention.

FIG. 2 is a sectional view taken along the line A-C in FIG.

3 is a sectional view taken along line B-C of FIG.

4 is a cross-sectional view taken along the line DD of FIG.

5 is a cross-sectional view taken along the line EE of FIG.

FIG. 6 is a perspective view of the filter member according to the first embodiment.

FIG. 7 is a diagram showing a shield member of a filter member.

FIG. 8 is a plan view of the filter according to the first embodiment.

9 is a sectional view taken along line FF in FIG.

FIG. 10 is a diagram showing a relationship between a flow rate and a flow rate when a filter member having a honeycomb structure is used (A) and when a filter member bent in a chrysanthemum shape is used (A).

[Fig. 11] Fig. 11 is a diagram showing a charging potential in a case using a filter member having a honeycomb structure (A) and a case using a filter member bent into a chrysanthemum shape (A).

FIG. 12 is a plan view of a filter unit according to a second embodiment.

FIG. 13 is a side view seen from the H direction in FIG.

FIG. 14 is a plan view of a filter according to a second embodiment.

15 is a sectional view taken along line GG of FIG.

FIG. 16 is a plan view showing a state where an attachment member is attached to the filter.

FIG. 17 is a sectional view of a filter unit according to a third embodiment.

FIG. 18 is a sectional view of a filter according to a third embodiment.

FIG. 19 shows a filter member used in a conventional filter.

FIG. 20 is a diagram showing the relationship between discharge energy and charging potential with respect to the volume resistivity of the filter cover.

[Explanation of symbols]

1, 90, 100 filter unit 2, 91, 102 cases 7,107 Filter member 30 pumps 34 First-order filter 40 housing body 50, 70 Housing cap 80 Mounting part 85 sensor 86 Engagement part 95 Return passage 96 outlet 102 cases 114 Fuel outlet 117 Engagement part 118 holes 150 set plates 151 Engagement part 160 cover 161 holes 180 pressure regulator

─────────────────────────────────────────────────── ───

[Procedure amendment]

[Submission date] April 30, 2003 (2003.4.3)
0)

[Procedure Amendment 1]

[Document name to be amended] Statement

[Correction target item name] Full text

[Correction method] Change

[Correction content]

[Document name] Statement

Title: In-tank fuel filter

[Claims]

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fuel filter for removing foreign matters from fuel delivered from a fuel tank by a fuel pump. In particular, the present invention relates to an in-tank type filter installed and used in a fuel tank . In this specification, the fuel pump is simply referred to as a pump, the fuel filter is simply referred to as a filter, the fuel tank is simply referred to as a tank,
The filter used in the tank is called an in-tank filter.

[0002]

2. Description of the Related Art An example of an in-tank type filter is German Patent Application P4242422.6 (Japanese Patent Laid-Open No. 6-213091).
(Corresponding to the publication). In this technique, a filter having a substantially cylindrical shape is attached to the outer periphery of a pump having a substantially cylindrical shape to form a modular filter. This modular filter is used by being installed in the tank. The conventional modularized in-tank filter is very effective in simplifying the process of mounting the pump and the filter unit in the tank. Modularized for installation in this tank
Assemble the filter easily and efficiently when assembling it
It is hoped that this will be possible.

[0003]

[Patent Document 1] JP-A-6-213091

[0004]

Therefore, the present invention is solved.
The task you are trying to do is easy and efficient when assembling.
Modularized in-tank that can be assembled
Formula fuel filter.

An intern installed in this tank
In the conventional fuel filter, there is also a problem in that no particular consideration has been given to the fact that the filter and the fuel are charged, respectively.
The solution is proposed in the original application of this case.

[0006]

[Means for Solving the Problems ] To solve the above problems
First, the in-tank fuel filter according to the present invention is
Supplying fuel from the tank to the fuel injection device
Pump and foreign matter in the fuel discharged from the pump
Filter unit containing a filter member for removing
Filter that is assembled as a unit and modularized
Is fixed in the fuel tank. So
The first aspect of the present invention is based on the above premise means
Directly or by
Fuel tank through the housing member that covers the one-piece member
Engages with a set plate member that is integrally attached to
And the pump is attached to the integrated component.
Hold the cover member for holding it by engaging it with the one-piece member.
Characterized as a filter that is attached and modularized
And According to the first invention, the filter module is
In order to convert it into a single piece,
Housing member for covering, set plate member, cover member
Each attachment of can be modularized by engaging
Therefore, it can be done easily and easily. Also, the mounting of the engagement
It is easy to remove and it is easy to remove.
Wear. That is, it is possible to attach and detach the above-mentioned components.
The work is easy and easy.

A second aspect of the present invention is based on the above premise means.
Of the integrated product, which is the assembly of the pump and the filter unit.
Or through the housing member that covers the integrated component member,
Set plate member integrally attached to the tank
It is attached by engaging with and is attached to the integral component member.
Install the primary filter on the suction side of the worn pump,
The feature is that it is a modularized filter. This
According to the second invention, the filter is modularized.
Hitting the integrated component or covering the integrated component
The mounting member and the set plate member by engaging
Because it can be made into a module, it can be done easily and easily
It Also, it is easy to remove because it is an engaging attachment.
Can be done easily. That is, between the above components
It is possible to attach and detach, and the work is easy and easy.
I can. According to the second aspect of the invention,
The primary filter, which is installed on the inlet side of the
It is made into a joule.

A third invention is the first or second invention mentioned above.
In the light, pressure is applied to the fuel outlet of the filter unit.
Is equipped with a regulator.
According to the third invention, the above-mentioned first or second invention is provided.
In addition to the pressure regulator is a filter unit
Since it is installed at the fuel outlet of the
It will be modularized including the generator. The fourth invention is before
In any one of the first to third inventions described above,
The fuel filter is attached to the filter unit from its upper part along the outer peripheral surface.
A turn passage is provided and a lower side wall of the fuel return passage is provided.
Has an outlet for discharging return fuel into the fuel liquid.
It is characterized by being. According to the fourth invention,
In addition to the first to third inventions described above, the return fuel is
Since it is guided into the fuel liquid by the turn passage,
Buzz can be reduced.

A fifth invention is the above-mentioned first to fourth inventions.
In any one of the inventions,
On the outer surface of the housing member that covers the filter unit,
It is installed in sensors such as fuel gauges and thermistors.
There is a mounting part that can be assembled by engaging the engaging part.
It is characterized by According to the fifth aspect,
In addition to the first to fourth inventions, a filter unit or
The outer surface of the housing member covering the filter unit is burned.
Install a sensor such as a charge gauge or thermistor
Can be converted into The sixth invention is from the above-mentioned first invention.
In any one of the fifth invention, a pump and a fill
The one-piece component with the built-in
A cylindrical filter member is concentrically arranged around the pump
It is characterized by being. According to this sixth invention
For example, in addition to the above-mentioned first to fifth inventions,
Since the filter members are arranged concentrically, they are both efficient
Can be placed easily. The seventh invention is the above-mentioned fifth or sixth invention.
In the invention, a filter unit or the filter unit
The housing member covering the cover is formed in a D-shaped cross section.
The cut part of this D-shaped section is used as the mounting part.
With sensors such as fuel gauges and thermistors
It is characterized by being According to this seventh invention,
In addition to the fifth or sixth invention, the fuel gauge and thermistor
Installation of the cut part with a D-shaped cross section such as a star
Since it is placed in the section, it is modularized with a sensor attached.
The outer diameter of the filtered filter is
Approximately the same as the outer diameter of the housing member that covers the filter unit
Becomes The result is a modular filter
It can be easily inserted through the mounting hole provided on the
It

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION The best mode for carrying out the present invention will be described below. [First Embodiment] First, the filter member 7 will be described. As shown in FIG. 7 (a), this filter member is formed by folding a sheet-shaped filter material 7D along a large number of parallel lines and bending it into a substantially C-shape. A substantially C-shaped upper end plate 7A is fixed to the upper surface of the filter material 7D, a substantially C-shaped lower end plate 7C is fixed to the lower surface, and a pair of side end plates 7B and 7B are fixed to the pair of side ends. Has been done. There is no gap between the filter material 7D and each of the end plates 7A, 7B, 7B, 7C, and they are fixed in a liquid-tight manner. Each end plate 7A, 7B, 7
An elastic shield member 8 (8
A, 8B, 8B, 8C) are adhered. These shield members 8 come into close contact with the inner wall of the case 2 when the filter member 7 is housed in the case 2 described later. In addition,
As the filter member 7, various filter members such as a honeycomb structure filter member and a vortex structure filter member can be used in addition to the filter member 7D obtained by bending a filter medium. Alternatively, the shield member 20 shown in FIG. 7B can be used.

Next, the case 2 in which the filter member 7 is housed
Will be described. 1 to 3 show a state where the filter member 7 is housed in the case 2, and the whole thereof is called a filter unit 1. 1 is a plan view of a filter unit 1 of the first embodiment, FIG. 2 is a sectional view taken along the line A-C of FIG. 1, and FIG. 3 is a sectional view taken along the line B-C of FIG.

As shown in FIGS. 1 to 3, the case 2 of the filter unit 1 is composed of a case body 2A and a case cap 2B, both of which are made of conductive resin or non-conductive resin. The case main body 2A is a bottomed double cylinder composed of an inner peripheral wall 3, an outer peripheral wall 4, and a substantially annular bottom wall 3A connecting the peripheral walls 3 and 4. As shown in FIG. 1, the case 2 has a substantially D-shaped cross section. That is, as well shown in FIG.
The outer peripheral wall 4 is cut in a part in the circumferential direction, and the circumferential end 4A of the cut outer peripheral wall 4 and the inner peripheral wall 3 are connected by a side wall 3B. The case 2 and the filter unit 1 are constructed by inserting the filter member 7 into the space having an approximately C-shaped cross section between the inner peripheral wall 3 and the outer peripheral wall 4 and then closing the upper opening of the case main body 2A with the case cap 2B. It At this time, the substantially C-shaped shield member 8A of the filter member 7 strongly contacts the case cap 2B to prevent fuel from passing through the gap between the filter member 7 and the case cap 2B. Further, the substantially C-shaped shield member 8C strongly contacts the bottom plate 3A to prevent fuel from passing through the gap between the filter member 7 and the bottom plate 3A. Further, the substantially linear shield members 8B, 8B strongly abut against the side walls 3B, 3B to prevent fuel from passing through the gap between the filter member 7 and the side wall 3B. That is, four rounds of the filter member 7 are strongly pressed against the inner surface of the case 2, and the space between the inner circumferential wall 3 and the outer circumferential wall 4 having a substantially C-shaped cross section is liquid-tightly partitioned by the filter member 7.
When the filter member 7 or the case 2 itself has a sealing action, the space outside the filter member 7 and the space inside can be liquid-tightly partitioned without using the shield member 8.

As best shown in FIGS. 2 and 3, the case cap 2B is provided with an inflow side mounting hole 11. The inflow side attachment hole 11 communicates with the fuel inflow chamber 9 (referred to as a space surrounded by the filter member 7 and the outer peripheral wall 4) via the passage 12 and the fuel inflow port 13. Further, the case cap 2B is provided with an outflow side attachment hole 15 as well shown in FIG. The outflow-side mounting hole 15 is connected to the fuel outflow chamber 10 (filter member 7) via the fuel outflow port 14.
And the space surrounded by the inner peripheral wall 3).
This is well shown in FIG. 1 in order to form a large fuel inlet 13 on the outer peripheral side of the filter member 7 (more accurately, the shield member 8) and a large fuel outlet 14 on the inner peripheral side. Thus, the approximately C-shaped shield member 8 is fixed at a position offset from the center of curvature of the filter member 7. On the right side of FIG. 1, the outer peripheral side is largely secured by the inner side of the shield member 8, and on the left side, the inner peripheral side is largely secured by the outer side of the shield member 8. Therefore, the opening areas of both the fuel inlet 13 and the fuel outlet 14 can be sufficiently secured.

As best shown in FIGS. 1 and 2, a cylinder 16 is formed on the upper surface of the case cap 2B for receiving return fuel from the engine or the pressure regulator. The bottom of the cylinder 16 is closed by the case cap 2B, and instead, a plurality of openings 17 are formed in the side portion. The fuel flowing into the cylinder 16 flows out from the plurality of openings 17, and radially flows out from the cylinder 16 on the surface of the case cap 2B. The case cap 2B has an opening 2C formed in the upper portion of the pump housing space 5, and when the remaining fuel in the tank is small and the opening 2C projects upward from the liquid level of the remaining fuel, the case cap 2B is formed. A part of the fuel flowing on the surface of the above flows into the opening 2C. Case body 2A
The inner space of the inner peripheral wall 3 is a space 5 for accommodating the pump 30, and as shown in FIG. 9, the pump 30 is opened from the lower opening 6 of the case body 2A to the pump accommodating space 5. Inserted in. The pump 30 is inserted into the pump housing space 5, and the discharge port 31 of the pump 30 is connected to the inlet side mounting hole 11 of the case 2 via the spacer 32 and the bush 33.

A slight gap is formed between the pump 30 and the inner peripheral wall 3 so that the remaining fuel in the tank is small and the module and the opening are open even when the module is exposed above the liquid surface of the remaining fuel. 17 and the return fuel flowing through the upper surface of the case cap 2B and the opening 2C of the case cap 2B,
It flows into the gap between the pump 30 and the inner peripheral wall 3, and the return fuel fills the gap. Further, most of the fuel flowing on the surface of the case cap 2B flows along the outer peripheral wall of the case body 2A. For this reason, after the flow velocity of the returning fuel is sufficiently reduced, the returning fuel drops to the liquid surface of the remaining fuel, and the dropping sound of the returning fuel is silenced. Pump 3
The integrated unit in which 0 and the filter unit 1 are assembled is further housed in the housing. The integrated product housed in this housing is simply called a filter. The housing is composed of a housing body 40 and a housing cap 50, both of which are made of non-conductive resin. In this case, the housings 40, 50 are the covers forming the surface of the filter.

The housing body 40 has a cylindrical shape having an opening 40A on the bottom surface and is open at the upper side, and an integrated product in which the pump 30 and the filter unit 1 are assembled is inserted from the upper opening. Reference numeral 41 in the figure denotes a support member formed of a non-conductive material such as a non-conductive resin.
The housing body 40 has a D-shaped cross section according to the outer shape of the case 2. When the integrated product in which the pump 30 and the filter unit 1 are assembled is inserted into the housing body 40, the fuel suction port of the pump 30 formed at the lower end of the pump 30 protrudes from the opening 40A, and the bag-shaped first portion is formed therein. The next filter 34 is attached. A return pipe mounting portion 56 for returning fuel and a feed pipe mounting portion 58 for sending fuel out of the tank are fixed to the housing cap 50 by penetrating the housing cap 50. The opening 54 on the lower side of the cap of the feed pipe mounting portion 58 is formed at a position corresponding to the outflow side mounting hole 15 of FIG. 1, and the opening 57 on the lower side of the cap of the return pipe mounting portion 56 is formed on the tube 16 of FIG. It is formed at the corresponding position.

When the housing cap 50 is fixed to the upper end 42 of the housing body 40, the outflow side mounting hole 15 of the case 2 is connected to the opening 54 of the feed pipe mounting portion 58 via the fuel supply pipe 60 and the O ring 61. . Further, the opening 57 of the return pipe attachment portion 56 faces the cylinder 16 formed in the case 2. The opening 57 and the tube 16 may be connected by a hose. Reference numeral 52 denotes a cushion, which positions the integrated body in which the pump 30 and the filter unit 1 are assembled and the housing (the housing body 40 and the housing cap 50). Reference numeral 53 is a power supply connector, and the pump 30 is connected to the connector 53.
Connect the power terminal of. Integrated product with pump 30 and filter unit 1 assembled and housing (40, 50)
Are integrated to form a filter. This filter is inserted and fixed in a tank (not shown). The surface of this filter is a non-conductive resin cover (housing 4
0,50). The housing cap 50 of the first embodiment corresponds to the set plate 150 (see FIG. 18) in the third embodiment described later.

Next, the operation of this filter will be described. The pump 30 sucks the fuel in the tank through the primary filter 34, and from the discharge port 31 to the passage 12 and the fuel inlet port 13.
The fuel is fed into the fuel inflow chamber 9 via. Fuel inflow chamber 9
The fuel sent in passes through the filter material 7D of the filter member 7 in the radial direction and is sent to the fuel outflow chamber 10, where it is filtered. The filtered fuel is the fuel outlet 14,
It is sent out to the feed pipe mounting portion 58 through the fuel supply pipe 60 and the passage 55. A feed pipe (not shown) is connected to the feed pipe attachment portion 58, and the other end side of the feed pipe is connected to the fuel injection device. Also,
A pressure regulator (not shown) is connected to the feed pipe (not shown), and releases the fuel when the fuel pressure in the feed pipe exceeds a predetermined value. A return pipe is connected to this fuel escape port. The fuel discharged to the return pipe is guided from the return pipe mounting portion 56 into the inside of the cylinder 16, and the plurality of openings 1
7 flows out onto the surface of the case cap 2B. Part of the fuel that has flowed out flows down through the gap between the pump 30 and the inner peripheral wall 3 of the case 2. Most of the return fuel flows down through the gap between the outer peripheral wall 4 of the case 2 and the housing body 40. That is, the inner peripheral wall 3 and the outer peripheral wall 4 of the case 2 and the inner surface of the housing main body 40 are always kept in contact with the fuel.

The fuel returned from the return pipe flows down along the outer circumference of the pump 30 and the outer circumference of the case body 2A. Since these flow passages have a long circumference, the flow passage has a large cross-sectional area, and the fuel slowly flows in a thin film around the pump 30 and the case body 2A. For this reason, the sound generated with the return of fuel is suppressed. This embodiment, as a filter member,
As best shown in FIG. 6, a fuel is used to pass through in the radial direction, and the outermost surface of the filter is formed of a non-conductive member. When this filter is used in the tank, the charging potential generated on the filter member is suppressed to a low level in the first place, and corona discharge is generated from the surface of the filter to suppress the surface potential of the filter to a low level. Furthermore,
It has been confirmed that spark discharge does not easily occur because the surface of the filter is made of a non-conductive material having high volume resistance. If the surface of the filter is made non-conductive, the electric charge accumulated on the surface of the filter (in this case, the housing body 40) may suddenly flow even if the surface of the filter comes into contact with a tank or the like during work or the like. The occurrence of spark discharge is effectively suppressed.

FIG. 20 shows the relationship between the volume resistivity of the member forming the surface of the filter and the discharge energy.
When the volume resistivity is 108 to 1010 ohm · cm, the discharge energy is suppressed low, and at the same time, the charging potential is also suppressed low. The range of 108 to 1010 ohm · cm is a range in which both are balanced, and the material of the filter case is preferably selected from those having a volume resistivity within the above range. Further, in the case of this embodiment, the return fuel is caused to flow along the surface of the case 2 to prevent excessive charge from being accumulated on the surface of the case 2. In this embodiment, the filter member 7 is housed in the case 2, and the case 2 is housed in the housings 40 and 50. That is, the filter member 7 is doubly covered.

Further, in this embodiment, the return fuel is caused to flow along the surfaces of the case 2 and the housings 40, 50 to reduce the charge accumulated on the surfaces of the case 2 and the housings 40, 50. The effect of reducing the charge by flowing this return fuel along the case or housing is that the amount of fuel remaining in the tank decreases, the contact area between the housing and the fuel in the tank decreases, and the charge on the filter surface discharges. It is effective when it becomes difficult to do. Since the return fuel is received by the cylinder 16 and flows through a wide range on the surface of the case cap 2B from the plurality of openings 17, the charging potential of the case 2 or the housing can be uniformly lowered over the entire surface. . In the case of a filter member having a substantially cylindrical shape, as shown in FIG. 6, in the case of a type in which fuel is flowed in the radial direction for filtration, the filtration area is the length in the circumferential direction multiplied by the height. . On the other hand, as shown in FIG. 19, the passage area in the case where the fuel is filtered by flowing the fuel in the axial direction is the circumferential length multiplied by the thickness of the filter medium. Of course, the former is usually much larger than the latter. Therefore, if the amount of filtered fuel per unit time is the same, the passage speed with the former filter is slower than the passage speed with the latter filter. FIG. 10 shows the relationship between the flow rate and the flow velocity. A shows the relationship when flowing in the axial direction, and A shows the relationship when flowing in the radial direction. Clearly, for the same flow rate, the axial flow rate is faster than the radial flow rate.

The charge amount (charge potential) generated in the filter when the fuel passes through the filter is affected by the fuel passage speed, and the faster the flow velocity, the higher the charge potential. Figure 1
1 shows the relationship between the flow velocity and the charging potential. The type (a) in which the flow velocity is in the axial direction has a high charging potential, and the type (a) in which the flow velocity is in the radial direction has a low charging potential. In practice, the charge potential developed on the filter is also affected by the time it takes for the fuel to pass through the filter. When flowing in the radial direction, the contact time between the fuel and the filter is short because the flow velocity of the fuel is slow but the thickness of the filter member is not so large. On the other hand, in the case of flowing in the axial direction, since the flow velocity has to pass through the height of the filter member at the earliest, the contact time between the fuel and the filter is long. From these things, by using the filter that flows in the radial direction, the amount of charge generated by the filter can be significantly reduced as compared with the case of using the filter that flows in the axial direction. In this embodiment, the filter member is doubly covered with the case and the housing. On the other hand, the cover that covers the filter member may have a single-layer structure. For example, the case 2 may be the outermost surface without using the housing.

[Second Embodiment] Next, a second embodiment will be described with reference to FIGS. In the figure, a case 91 of the filter unit 90 is provided with a return passage 95 from the upper part of the case 91 along the outer peripheral surface. The return passage 95 has a circular cross section at the upper part of the case 91 so as to be opposed to or connectable to the return pipe or the discharge port of the pressure regulator, and the portion along the side surface of the case 91 has a semicircular cross section. There is. A discharge port 96 for discharging the return fuel into the fuel liquid is provided on the lower side wall of the return passage 95. The return passage 95 forms an additional fuel passage. The other configuration is the same as that of the filter unit 1 shown in FIGS.

In this embodiment, since the return fuel is guided into the fuel liquid by the return passage 95, the return sound can be further reduced. The cross-sectional shape of the return passage 95 can be various shapes other than circular and semicircular, and the number of return passages 95 may be plural.
Further, it is preferable that the return passage is integrally formed with the case by using synthetic resin or the like. 14 and 15, in addition to the pump 30 and the housings 40 and 70 in the filter unit 1 shown in FIGS.
FIG. 15 shows a filter in which 0 is also attached, and FIG.
FIG. 3 is a sectional view taken along line G-G of FIG. Similar to the filter shown in FIGS. 8 and 9, the fuel pump 30 is assembled to the case 2 of the filter unit 1, and the case 2 is housed in the housing body 40. Then, the housing cap 70 is attached to the housing body 40. At this time, the pressure regulator 180 is provided between the outflow side mounting hole 15 provided in the case 2 and the mounting hole 74 provided in the housing cap 70.
Is attached via the O-ring 61. The mounting hole 74 is connected to the feed pipe mounting portion 76 via the passage 75. The fuel outlet of the pressure regulator 180 faces the cylinder 16 for receiving the return fuel, or is connected to the cylinder 16. Similar to the module shown in FIGS. 8 and 9, the power supply connector 73 is connected to the power supply terminal of the fuel pump 30, and the cushion 52 and the primary filter 34 are attached.

The operation of the modularized filter shown in FIGS. 14 and 15 will be described. The fuel sucked by the fuel pump 30 has a discharge port 31, a passage 12, a fuel inlet port 13, a fuel inflow chamber 9, a filter member 7, and a fuel outflow chamber 1.
0, sent to the pressure regulator 180 via the fuel outlet 14. Pressure regulator 180
Discharges the fuel from the fuel discharge port to the return fuel receiving cylinder 16 when the pressure of the fuel in the passage 75 is equal to or higher than the set pressure. The fuel discharged to the cylinder 16 is returned to the fuel liquid along the surface of the case 2 through the plurality of openings 17 connected to the cylinder 16. As a result, the fuel pressure in the passage 75 is maintained at the set pressure. The fuel adjusted to the set pressure is
It is supplied to the fuel injection device via a feed pipe attachment portion 76 and a feed pipe (not shown).

FIG. 16 is a diagram in which accessories such as a sensor are assembled to the modularized filter. A mounting portion 80 is provided in a portion cut from the cylindrical shape of the housing 40 having a D-shaped cross section, and a groove 81 provided in the mounting portion 80 is provided in a sensor 85 such as a fuel gauge or a thermistor. The sensor 85 is attached to the housing 40 by engaging the engaging portion 86 provided.
Attach to. Since an accessory such as a sensor is attached to a portion cut from the cylindrical shape of the housing 40, the outer diameter of the filter to which the accessory is attached is equal to the housing 4
It is almost the same as the outer diameter of 0. Therefore, the modularized filter can be inserted through the circular mounting hole provided in the tank.

[Third Embodiment] In the above embodiments, the case is housed in the housing, and the housing is made of a non-conductive material. However, the case can also be used as the housing. This embodiment is shown in FIGS. 17 and 18.
Note that FIG. 17 shows a sectional view of the filter unit, and FIG. 18 shows a sectional view of a filter in which a pump and the like are assembled in the filter unit. In this case, the surface of the filter consists of the case. The case 102 of the filter unit 100 is made of a non-conductive material such as a non-conductive resin, and is provided with an inner peripheral wall 103 and an outer peripheral wall 104. Inner wall 10
A filter member 107 is attached by a shield member 108 between the outer peripheral wall 104 and the outer peripheral wall 104 so that a fuel outflow chamber and a fuel inflow chamber are formed on the inner peripheral side and the outer peripheral side. At the fuel outlet 114 communicating with the fuel outlet chamber,
The outflow side mounting hole 115 is provided, and the mounting hole 116 for mounting the pressure regulator is also provided. Further, a hole 118 for mounting the set plate is provided in the upper part of the case 102, and the pump 3 is provided in the lower part.
An insertion opening 106 for inserting 0 and an engaging portion 117 for attaching the cover 160 are provided.

In order to construct a filter by assembling the pump 30 etc. to the filter unit 100 as described above, the case 1 is used.
The pump 30 is inserted through the insertion port 106 of No. 02, and the pressure regulator 180 is attached to the attachment hole 116. Next, by engaging the engaging portion 151 with the hole 118 provided in the case 102, the set plate 1
Attach 50 to case 102. At this time, the case 102
The fuel supply pipe 155 is attached between the outflow side mounting hole 115 provided in the mounting plate 150 and the mounting hole 154 provided in the set plate 150. Further, after the primary filter 34 is attached to the suction port of the fuel pump 30, the cover 160 is attached to the case 102 by engaging the engaging portion 117 provided on the case 102 with the hole 161.

In the above embodiment, the fuel filter unit is assembled with the fuel pump or the like to form the filter. However, the fuel filter unit may be installed alone in the tank and used. Although the case has a D-shaped cross section, it may have various shapes such as a circular shape and a C shape. Further, although the housing or the case is made of a non-conductive material and the return fuel is made to flow along the surface of the case, only one of them may be used. Also,
Although the structure in which the case is housed in the housing or the structure in which the case is also used as the housing has been described, the fuel filter is not limited to such a structure, and the spark discharge is most generated when the fuel filter comes into contact with the tank etc. Since it is easy, at least the outer peripheral portion that is likely to come into contact with the tank or the like may be formed of a non-conductive material.

[0030]

As described above, the intern of the present invention is used.
According to the fuel filter, the filter is modularized.
When mounting each member by engaging with each other
Therefore, it is easy and easy to assemble the module.
It can be done easily. Also, it is necessary to install the engagement.
Therefore, it can be removed easily and easily. sand
That is, it is possible to attach and detach the above-mentioned components.
The work is easy and easy.

[Brief description of drawings]

FIG. 1 is a plan view of a filter unit of a first embodiment used in a filter of the present invention.

FIG. 2 is a sectional view taken along the line A-C in FIG.

3 is a sectional view taken along line B-C of FIG.

4 is a cross-sectional view taken along the line DD of FIG.

5 is a cross-sectional view taken along the line EE of FIG.

FIG. 6 is a perspective view of the filter member according to the first embodiment.

FIG. 7 is a diagram showing a shield member of a filter member.

FIG. 8 is a plan view of the filter according to the first embodiment.

9 is a sectional view taken along line FF in FIG.

FIG. 10 is a diagram showing a relationship between a flow rate and a flow rate when a filter member having a honeycomb structure is used (A) and when a filter member bent in a chrysanthemum shape is used (A).

[Fig. 11] Fig. 11 is a diagram showing a charging potential in a case using a filter member having a honeycomb structure (A) and a case using a filter member bent into a chrysanthemum shape (A).

FIG. 12 is a plan view of a filter unit according to a second embodiment.

FIG. 13 is a side view seen from the H direction in FIG.

FIG. 14 is a plan view of a filter according to a second embodiment.

15 is a sectional view taken along line GG of FIG.

FIG. 16 is a plan view showing a state where an attachment member is attached to the filter.

FIG. 17 is a sectional view of a filter unit according to a third embodiment.

FIG. 18 is a sectional view of a filter according to a third embodiment.

FIG. 19 shows a filter member used in a conventional filter.

FIG. 20 is a diagram showing the relationship between discharge energy and charging potential with respect to the volume resistivity of the filter cover.

[Explanation of symbols] 1, 90, 100 filter unit 2, 91, 102 cases 7,107 Filter member 30 pumps 34 First-order filter 40 housing body 50, 70 Housing cap 80 Mounting part 85 sensor 86 Engagement part 95 Return passage 96 outlet 102 cases 114 Fuel outlet 117 Engagement part 118 holes 150 set plates 151 Engagement part 160 cover 161 holes 180 pressure regulator

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Hironori Ueda             1 Ai 1-1-1, Kyowa-cho, Obu City, Aichi Prefecture             Sankogyo Co., Ltd.

Claims (14)

[Claims] 1. A filter having a substantially cylindrical filter member attached to the outer periphery of a substantially cylindrical pump, which is installed and used in a tank. The member forming the surface of the filter is a non-conductive member. A filter characterized in that the filter member having a substantially cylindrical shape is a filter member of a type in which a fuel is caused to flow in a radial direction to filter foreign matters. 2. A filter that is used by being installed in a tank with a substantially cylindrical filter unit assembled on the outer periphery of a substantially cylindrical pump and covered with a substantially cylindrical housing. A filter comprising a non-conductive member. 3. The filter according to claim 2, wherein the case of the filter unit is made of synthetic resin. 4. The filter according to claim 2, wherein the substantially cylindrical filter unit is a filter unit of a type in which a fuel is caused to flow in a radial direction to filter foreign matters. 5. The filter according to claim 2, wherein gaps into which fuel enters are provided between the outer circumference of the pump and the inner circumference of the filter case, and between the outer circumference of the filter case and the inner circumference of the housing, respectively. A filter characterized by being formed. 6. The filter according to claim 2, wherein a case for housing the filter member is formed with a return fuel receiving portion. 7. The filter according to claim 2, wherein a return fuel receiving portion is formed in a case of the filter unit. 8. The filter according to claim 1, wherein the filter member has a shape in which a sheet-shaped filter medium is folded back along a large number of parallel lines, and the whole is curved. 9. The filter according to claim 2, wherein the filter member has a shape in which a sheet-shaped filter medium is folded back along a large number of parallel lines and the whole is curved. 10. The filter according to claim 1, wherein a pressure regulator is assembled. 11. The filter according to claim 2, wherein a pressure regulator is assembled. 12. A filter having a substantially cylindrical filter unit attached to the outer periphery of a generally cylindrical pump, which is installed and used in a tank. A member forming a surface of the filter unit is made of a non-conductive material. A filter comprising a member and having a substantially cylindrical shape as a filter unit of a type in which fuel is radially flowed to filter foreign matters. 13. A cover of a substantially cylindrical filter member installed in a tank is formed of a non-conductive resin, and
An in-tank filter in which the substantially cylindrical filter member is a type of filter member that allows fuel to flow in the radial direction for filtering. 14. The in-tank filter according to claim 13, wherein the non-conductive cover has a volume resistivity of 10 or less.
In-tank type filter made of 8 to 1010 ohm-cm resin.