JP2016191339A - Fuel supply device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reliably detect clogging of a suction filter while distinguishing it from engine malfunction caused by running-out of fuel in a fuel tank.SOLUTION: When a fuel liquid level of a fuel tank T becomes lower than a lower end of an opening portion 43, a gas in the fuel tank T passing through the opening portion 43 is sucked to a fuel pump 13 from a vapor discharge passage 26, which causes failure, thus clogging of a suction filter 24 of the fuel pump 13 can be detected. Only by simple design change by changing a height of a lower end of the opening portion 43 (height of an upper end of a surrounding wall 26b), a maximum fuel level L of the fuel tank T in which a gas is sucked to the fuel pump 13 can be easily adjusted, costs can be reduced in comparison with a case when a design of a strainer 27 of which a structure is complicated due to a filter 28, is changed.SELECTED DRAWING: Figure 4

Description

  The present invention provides a housing that is mounted so as to close an opening of a fuel tank, a fuel pump that is supported by the housing and discharges fuel sucked from a suction port via a suction filter from the discharge port, and the fuel pump A vapor discharge hole for discharging vapor generated in the fuel, a vapor discharge passage having one end connected to the vapor discharge hole and the other end extending above the vapor discharge hole, and the vapor discharge passage. The present invention relates to a fuel supply device including a strainer connected to the other end and having a mesh filter on an outer peripheral surface.

  Such a fuel supply apparatus is already known as disclosed in Patent Document 1. The fuel supply apparatus described in FIGS. 1 and 2 of Patent Document 1 is provided with a strainer 20 having a filter 58 made of a porous body at the upper end of a vapor discharge passage 42 extending upward from the vapor discharge hole 40 of the fuel pump 18. ing. Therefore, in a state where the fuel level of the fuel tank is lower than the filter 58, the suction filter (not shown) provided at the suction port 32 of the fuel pump 18 is clogged, and the vapor discharge hole 40 becomes negative pressure. Then, the gas sucked into the fuel pump 18 from the filter 58 through the vapor discharge passage 42 and the vapor discharge hole 40 is supplied to the engine, and the engine causes a malfunction such as breathing, so that the suction filter of the fuel pump is clogged. Can be detected.

  The present applicant has proposed a fuel supply apparatus having a strainer having a similar function by Japanese Patent Application No. 2014-69877. In this fuel supply device, a cylindrical strainer having a plurality of filters on the outer peripheral surface is connected to the upper end of the vapor discharge passage, and an opening (orifice) is provided at the lower end of a cover member that covers the outer periphery of the strainer. It communicates with the inside.

JP 2013-117198 A

  By the way, when the fuel in the fuel tank is emptied, gas is mixed with the fuel supplied from the fuel pump to the engine as in the case where the suction filter is clogged. It is necessary to distinguish whether the malfunction is caused by the fuel in the fuel tank being emptied or the intake filter of the fuel pump is clogged. That is, if the fuel level is low when gas is supplied to the engine due to clogging of the suction filter, it is difficult to distinguish from the case where the fuel in the fuel tank is emptied and the gas is supplied to the engine. It becomes difficult to identify the cause of the malfunction.

  In the one proposed by Japanese Patent Application No. 2014-69877, when the fuel pump suction filter is clogged, the engine malfunctions if the fuel level falls below the height of the lower end of the strainer filter. By changing the design so that the height of the lower end of the fuel tank becomes higher, the suction filter can reliably detect clogging, as distinguished from the case where the fuel in the fuel tank becomes empty and the engine malfunctions.

  However, the strainer has a complicated shape for assembling a plurality of filters. To change the design of the strainer, there is a problem that the cost of a mold for forming the strainer increases.

  The present invention has been made in view of the above-described circumstances, and adjusts the maximum liquid level of fuel that is sucked into the fuel pump from the vapor discharge passage when the suction filter is clogged without changing the design of the strainer. The purpose is to be able to.

  In order to achieve the above object, according to the first aspect of the present invention, there is provided a housing that is mounted so as to close the opening of the fuel tank, and is supported by the housing and from the intake port via the intake filter. A fuel pump for discharging the sucked fuel from a discharge port, a vapor discharge hole provided in the fuel pump for discharging vapor generated in the fuel, one end connected to the vapor discharge hole, and the other end discharging the vapor A fuel supply apparatus comprising: a vapor discharge passage extending above a hole; and a strainer connected to the other end of the vapor discharge passage and having a mesh-like filter on an outer peripheral surface thereof. An enclosure wall that surrounds the outer periphery of the strainer is provided, and is opened at a position higher than the lower end of the filter at an upper end or a side surface of the enclosure wall. Fuel supply device is proposed, characterized in that the openings are formed for communicating the space in the internal space of the fuel tank.

  According to the invention described in claim 2, in addition to the configuration of claim 1, the surrounding wall is integrally formed at the upper part of the vapor discharge passage, and the opening is formed at the upper end of the surrounding wall. A fuel supply device is proposed.

  According to a third aspect of the present invention, in addition to the configuration of the second aspect, the surrounding wall and the strainer are covered with a cover member from above, and the fuel in the fuel tank is filled above the cover member. A space that is not filled with fuel even if the amount is formed, a communication hole that communicates with the space is formed in the upper portion of the strainer, a vertically extending slit provided in a side wall of the cover member, and an upper end of the surrounding wall A fuel supply device is proposed in which the opening is formed between the two.

  The first housing 11 of the embodiment corresponds to the housing of the present invention, and the cover cylinder 36 of the embodiment corresponds to the cover member of the present invention.

  According to the configuration of the first aspect, the fuel supply device includes a housing that is mounted so as to close the opening of the fuel tank, and a fuel that is supported by the housing and sucked from the suction port via the suction filter from the discharge port. A fuel pump for discharging, a vapor discharge hole provided in the fuel pump for discharging vapor generated in the fuel, and a vapor discharge passage having one end connected to the vapor discharge hole and the other end extending upward from the vapor discharge hole And a strainer connected to the other end of the vapor discharge passage and having a mesh-like filter on the outer peripheral surface.

  When the fuel pump suction filter becomes clogged, the fuel pump vapor discharge hole becomes negative pressure. However, an upper wall or a side wall surrounding the outer periphery of the strainer is provided at the top of the vapor discharge passage. In addition, since the opening that opens to a position higher than the lower end of the filter and connects the inner space of the surrounding wall to the inner space of the fuel tank is formed, the fuel level of the fuel tank is higher than the lower end of the opening. The fuel flowing into the inner space of the surrounding wall from the opening passes through the filter of the strainer and is sucked into the fuel pump without any trouble. When the fuel level of the fuel tank becomes lower than the lower end of the opening, a small amount of fuel accumulated in the inner space of the surrounding wall passes through the opening after passing through the strainer filter and sucked into the fuel pump. Gas in the fuel tank is sucked into the fuel pump through the vapor discharge passage and the vapor discharge passage and the engine malfunctions, so that the clogging of the intake filter of the fuel pump can be detected.

  The maximum fuel liquid in the fuel tank into which gas is sucked into the fuel pump can be obtained simply by changing the height of the lower end of the opening without changing the design of the strainer, which has a complicated structure due to having a filter. Since the surface can be adjusted, the cost can be reduced compared to the case where the strainer is redesigned.

  According to the second aspect of the present invention, the surrounding wall is formed integrally with the upper portion of the vapor discharge passage, and the opening is formed at the upper end of the surrounding wall. Can be easily adjusted.

  According to the third aspect of the present invention, the surrounding wall and the strainer are covered with the cover member from above, and a space that is not filled with fuel even when the fuel in the fuel tank is full is formed on the upper portion of the cover member. A communication hole communicating with the space is formed in the upper part, and an opening is formed between the slit extending in the vertical direction provided on the side wall of the cover member and the upper end of the surrounding wall, so that the fuel in the fuel tank becomes empty When fuel is supplied to the fuel tank from the state in which the fuel pump has sucked gas, the gas in the fuel pump is discharged from the vapor discharge passage into the space in the cover member through the vapor discharge passage and the communication hole of the strainer. The fuel pump can be filled with fuel to prevent idling.

  Further, since the opening is covered with the cover member, when the fuel level fluctuates in a state where the fuel level of the fuel tank is lower than the lower end of the opening, fuel enters the internal space of the cover member from the opening. By suppressing this, gas can be sucked into the fuel pump from the vapor discharge passage, and clogging of the suction filter can be reliably detected. Moreover, if it is within the slit range of the cover member, the height of the lower end of the opening can be changed simply by changing the height of the upper end of the strainer enclosure wall, so that the gas is sucked into the fuel pump while using the same cover member The maximum fuel level of the fuel tank can be adjusted.

The perspective view of the fuel supply apparatus which concerns on embodiment of this invention. The disassembled perspective view of the fuel supply apparatus. FIG. 3 is a sectional view taken along line 3-3 in FIG. 1. FIG. 4 is a sectional view taken along line 4-4 of FIG.

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

  1 to 4, the fuel in the fuel tank T is supplied to the fuel injection valve (not shown) of the engine on the bottom plate Ta (see FIGS. 3 and 4) of the fuel tank T mounted on the vehicle. The fuel supply device D of the present embodiment is attached.

  The fuel supply apparatus D includes a first housing 11 made of synthetic resin attached to a bottom plate Ta of a fuel tank T, and a second housing made of synthetic resin connected to the first housing 11 and disposed in the fuel tank T. 12 and a fuel pump 13 held between the first housing 11 and the second housing 12.

  The first housing 11 is provided with a fuel take-out pipe 14 at the lower part, and has a bottomed cylindrical shape having an attachment flange 15 attached around the opening part Tb of the bottom plate Ta of the fuel tank T to close the opening part Tb. A base portion 16, a pair of arc-shaped pump holding walls 17 rising from the bottom of the base portion 16, and an inner peripheral edge portion of the mounting flange 15 so as to surround a lower portion of the pump holding wall 17, An enclosure wall 19 defining a fuel reservoir 18 between the holding wall 17 and a lower descending fuel pipe 20 standing from the bottom of the base part 16 while communicating with the fuel take-out pipe 14 are integrally formed, and the lower part is lowered. The fuel pipe 20 is integrally connected to the inner peripheral portion of the enclosure wall 19. The fuel reservoir 18 receives the fuel in the fuel tank T through the notch 21 of the enclosure wall 19. The fuel take-out pipe 14 can supply fuel to a fuel injection valve of an engine (not shown).

  The pair of pump holding walls 17 are arranged so as to constitute mutually opposite side walls of the cylindrical body, and the fuel pump 13 is fitted on the inner periphery of these pump holding walls 17 from above. The fuel pump 13 has a suction port 22 protruding from the lower end surface thereof, and a T-shaped suction pipe 23 is connected to the suction port 22. The inlet of the suction pipe 23 is accommodated in a fuel storage unit 18. A suction filter 24 having a circular arc cross section is connected.

  In FIG. 4, a vapor discharge hole 25 for discharging vapor generated in the fuel pump 13 is provided at the lower end surface of the fuel pump 13, and the vapor discharge hole 25 is a communication hole 23 a formed inside the suction pipe 23. Is connected to the lower end of the L-shaped vapor discharge passage 26. The vapor discharge passage 26 extends upward along the side surface of the fuel pump 13, and a lower end of a cylindrical strainer 27 is connected to a large diameter portion 26 a formed at the upper end thereof. A filter 28 made of a mesh-like porous body is provided on the outer periphery of the upper half of the strainer 27, and the inside and outside of the strainer 27 communicate with each other through this filter 28. Further, a communication hole 27a is opened at the upper end of the strainer 27, and the inside and outside of the strainer 27 communicate with each other through this communication hole 27a. A cylindrical surrounding wall 26 b extends upward from the outer periphery of the large-diameter portion 26 a of the vapor discharge passage 26 so as to surround the outer periphery of the strainer 27, and the upper end of the surrounding wall 26 b is at the intermediate portion in the height direction of the filter 28. Has reached.

  2 and 3, the second housing 12 includes a pair of fitting walls 29 having an arc cross section, a discharge port receiving cylinder 30 that connects one side of the fitting walls 29, and a cylindrical shape. The regulator holding cylinder 31, the cylindrical reinforcing cylinder 33 that connects the other side portions of the fitting walls 29 while enclosing the regulator holding cylinder 31 through the gap 32 over substantially the entire length thereof, and the gap 32 are crossed. A plurality of radially arranged ribs 34 connecting between the regulator holding cylinder 31 and the reinforcing cylinder 33, an upper descending fuel pipe 35 connected to one side of the discharge port receiving cylinder 30, and one of the upper descending fuel pipes 35. A cover cylinder 36 connected to the side is integrally formed. The upper descending fuel pipe 35 and the regulator holding cylinder 31 are arranged on both sides of the discharge port receiving cylinder 30, and a communication fuel pipe 37 arranged linearly and horizontally so as to connect these three members 30, 31, 35. The second housing 12 is integrally formed. A communication hole 37 a is formed in the communication fuel pipe 37 to allow communication between the regulator holding cylinder 31, the discharge port receiving cylinder 30 and the upper descending fuel pipe 35. The opening of the communication hole 37a is closed by a plug 38.

  The pair of fitting walls 29 of the second housing 12 are arranged so as to constitute mutually opposite side walls of the cylindrical body, and the lower part thereof is fitted to the outer periphery of the small-diameter portion 13a at the upper part of the fuel pump 13 and is held by the pump. The inner wall of the wall 17 is fitted. The pump holding wall 17 and the fitting wall 29 cooperate to hold the fuel pump 13. The fuel pump 13 has a discharge port 39 protruding from its upper end surface, and the discharge port 39 is fitted to the inner periphery of the discharge port receiving cylinder 30 via a seal member 40. The upper descending fuel pipe 35 is fitted to the upper end portion of the lower descending fuel pipe 20 via a seal member 41. Therefore, the fuel discharged from the discharge port 39 of the fuel pump 13 is supplied from the communication hole 37 a to the fuel take-out pipe 14 through the upper descending fuel pipe 35 and the lower descending fuel pipe 20. Further, the outer cylinder 42a of the pressure regulator 42 is press-fitted into the inner periphery of the regulator holding cylinder 31, and the lower cylinder 42a is fixed by caulking the lower end portion of the regulator holding cylinder 31 inward.

  In FIG. 4, the cover cylinder 36 of the second housing 12 is fitted to the outer periphery of the surrounding wall 26 b and the large diameter portion 26 a while covering the strainer 27 at the upper end of the vapor discharge passage 26. A slit 36a is formed on the side surface of the cover cylinder 36 so as to extend in the vertical direction and open at the lower end. Through the opening 43 formed between the upper end of the slit 36a and the upper end of the surrounding wall 26b, the inside and outside of the cover cylinder 36 Communicate. Above the upper end of the slit 36a inside the cover cylinder 36, a space 36b that is not filled with fuel even when the fuel in the fuel tank T is full is formed.

  In FIG. 1, the sensor support arm 44 projects horizontally from one side of the reinforcing cylinder 33 of the second housing 12. A liquid level sensor 45 is attached to the tip of the sensor support arm 44, and a swing arm that supports the float 46 floating on the fuel level in the fuel tank T at the tip of the rotor 45a of the liquid level sensor 45. 47 are connected. Accordingly, when the fuel level in the fuel tank T rises or lowers due to fuel supply to the fuel tank T or fuel consumption in the engine, the float 46 rises and lowers accordingly. Is transmitted to the liquid level sensor 45, and the liquid level sensor 45 outputs a liquid level signal to a display unit (not shown).

  The first housing 11 and the second housing 12 include a plurality of locking claws provided in the fitting wall 29 of the second housing 12 in a plurality of locking holes 17 a provided in the pump holding wall 17 of the first housing 11. By engaging 29a, it is detachably coupled.

  Next, the operation of the embodiment of the present invention having the above configuration will be described.

  In FIG. 3, by the operation of the fuel pump 13, the fuel in the fuel tank T is filtered through the suction filter 24 of the fuel reservoir 18 and then sucked into the suction port 22 through the suction pipe 23. The fuel discharged from the discharge port 39 is supplied to the engine from the communication hole 37 a of the communication fuel pipe 37 through the upper down fuel pipe 35, the lower down fuel pipe 20 and the fuel take-out pipe 14. At this time, the pressure regulator 42 releases the excess pressure of the fuel discharged from the discharge port 39 of the fuel pump 13 into the communication hole 37a into the fuel tank T, and supplies the fuel from the fuel take-out pipe 14 to the fuel injection valve. The pressure is adjusted to a predetermined value.

  In FIG. 4, the vapor generated inside the fuel pump 13 is discharged from the vapor discharge hole 25 of the fuel pump 13 to the lower end of the vapor discharge passage 26, and the filter 28 of the strainer 27 connected to the upper end of the vapor discharge passage 26 or After passing through the communication hole 27a, the fuel is discharged from the opening 43 formed in the upper portion of the slit 36a of the cover cylinder 36 into the fuel tank T, thereby preventing vapor from being mixed into the fuel supplied to the engine. The

  Next, the case where fuel is supplied to the fuel tank T from the state where the fuel in the fuel tank T becomes empty and the gas (air / vapor mixture) is sucked into the fuel pump 13 will be described.

  3 and 4, when the fuel level in the fuel tank T gradually rises due to refueling and the fuel flows into the fuel reservoir 18, the fuel passes from the suction filter 24 through the suction pipe 23 and the suction port 22 to the fuel. Since the gas flows into the pump 13, the gas remaining in the fuel pump 13 is pushed out from the vapor discharge hole 25 to the vapor discharge passage 26. At this time, even if the filter 28 made of the porous body of the strainer 27 is clogged by getting wet with the fuel, the gas passes through the communication hole 27a at the upper end of the strainer 27 and covers the cover. It flows into the space 36b at the upper end of the cylinder 36 and is discharged from there through the opening 43 formed at the upper end of the slit 36a of the cover cylinder 36 into the internal space of the fuel tank T without any trouble. As a result, the fuel smoothly flows into the fuel pump 13 as the fuel level of the fuel tank T rises without being obstructed by the gas remaining in the fuel pump 13, so that the fuel pump 13 is idling. It is possible to supply the fuel to the engine without doing so.

  By the way, when the fuel pump 13 is used for a long period of time, the suction filter 24 for filtering the fuel is clogged by foreign matters contained in the fuel, and the vapor discharge hole 25 of the fuel pump 13 becomes negative pressure. There is.

  At this time, if the fuel level of the fuel tank T is higher than the lower end of the opening 43 of the cover cylinder 36 (see the fuel level L in FIG. 4), the fuel in the fuel tank T is generated by the negative pressure generated in the vapor discharge hole 25. Is sucked into the vapor discharge hole 25 from the opening 43 of the cover cylinder 36 through the filter 28 of the strainer 27 and the vapor discharge passage 26, and is supplied from the fuel pump 13 to the engine together with the fuel sucked from the suction port 22. Since the fuel sucked from the vapor discharge passage 26 has passed through the filter 28 of the strainer 27 and foreign matter has been removed, there is no possibility that foreign matter will be mixed into the fuel supplied to the engine.

  On the other hand, when the fuel level of the fuel tank T becomes lower than the lower end of the opening 43 of the cover cylinder 36 (see the fuel level L in FIG. 4) in a state where the suction filter 24 is clogged, the surrounding wall 26b initially. A small amount of fuel stored inside the gas passes through the filter 28 and is sucked into the fuel pump 13 from the vapor discharge passage 26. After the fuel level inside the surrounding wall 26b reaches the lower end of the filter 28, the vapor is discharged. The suction of fuel into the passage 26 is interrupted, and the gas in the fuel tank T is sucked into the fuel pump 13 through the opening 43, the filter 28, the vapor discharge passage 26 and the vapor discharge hole 25. As a result, gas is mixed with the fuel supplied from the fuel pump 13 to the engine, and the driver can be notified of clogging of the intake filter 24 due to malfunction such as the engine breathing.

  By the way, in addition to the case where the suction filter 24 of the fuel pump 13 is clogged, even when the fuel in the fuel tank T becomes empty, the gas is mixed with the fuel supplied from the fuel pump 13 to the engine. Therefore, it is desirable to be able to easily distinguish whether the malfunction is caused by clogging of the suction filter 24 or the fuel in the fuel tank T is emptied. If the fuel level L (the height of the lower end of the opening 43) when the gas is sucked into the engine due to the clogging of the suction filter 24 is low, the fuel in the fuel tank T is emptied, and the gas flows into the engine. Since it is difficult to distinguish from the case of being sucked, it is desirable to set the height of the lower end of the opening 43 as high as possible.

  In the invention described in Japanese Patent Application No. 2014-69877, the maximum liquid level of the fuel when the suction filter is clogged and gas is supplied to the engine is determined by the height of the lowest part of the filter in the strainer. In order to adjust the maximum liquid level of the fuel when gas is supplied, it is necessary to change the design of the entire strainer. However, the strainer has a complicated shape for assembling a plurality of filters, and there is a problem that the cost of the mold increases when the design is changed.

  On the other hand, according to the present embodiment, when adjusting the maximum liquid level L of the fuel when gas is supplied to the engine, the height of the lower end of the opening 43 is changed without changing the design of the strainer 27. In other words, it is only necessary to change the height of the upper end of the surrounding wall 26b of the vapor discharge passage 26, and the vapor discharge passage 26 is a member having a simple shape as compared with the strainer 27. It can be kept low. In particular, if the height of the lower end of the opening 43 can be changed only by changing the height of the upper end of the surrounding wall 26b of the strainer 27 within the range of the slit 36a of the cover cylinder 36, the same cover cylinder 36 is used. The maximum fuel level L of the fuel tank T into which gas is sucked into the fuel pump 13 can be adjusted.

  Further, since the opening 43 is covered with the cover cylinder 36, when the fuel liquid level fluctuates in a state where the fuel liquid level of the fuel tank T is lower than the lower end of the opening 43, the fuel flows from the opening 43 into the cover cylinder 36. By suppressing the intrusion into the space, gas can be stably sucked into the fuel pump 13 from the vapor discharge passage 26, and the clogging of the suction filter 24 can be reliably detected.

  The embodiments of the present invention have been described above, but various design changes can be made without departing from the scope of the present invention.

  For example, in the embodiment, the opening 43 is formed between the upper end of the surrounding wall 26 b and the slit 36 a of the cover cylinder 36, but the cover cylinder 36 is not essential, and the opening 43 is smaller than the lower end of the filter 28. It may be opened at a high position so that the inner space of the surrounding wall 26b communicates with the inner space of the fuel tank T. Therefore, the opening 43 does not necessarily have to be opened at the upper end of the surrounding wall 26b, and may be opened at the side surface of the surrounding wall 26b.

T fuel tank Tb opening 11 first housing (housing)
13 Fuel pump 22 Suction port 24 Suction filter 25 Vapor discharge hole 26 Vapor discharge passage 26b Enclosure wall 27 Strainer 27a Communication hole 28 Filter 36 Cover cylinder (cover member)
36a Slit 36b Space 39 Discharge port 43 Opening

Claims (3)

A housing (11) mounted so as to close the opening (Tb) of the fuel tank (T), supported by the housing (11), and sucked from the suction port (22) through the suction filter (24) A fuel pump (13) for discharging fuel from a discharge port (39), a vapor discharge hole (25) provided in the fuel pump (13) for discharging vapor generated in the fuel, and one end of the vapor discharge hole (25) connected to the other end of the vapor discharge passage (26) and the other end of the vapor discharge passage (26), the other end of which is connected to the vapor discharge hole (25). A fuel supply device comprising a strainer (27) having a filter (28);
An enclosing wall (26b) surrounding the outer periphery of the strainer (27) as viewed from above is provided at the top of the vapor discharge passage (26). The fuel supply device is characterized in that an opening (43) is formed which opens to a higher position and communicates the internal space of the surrounding wall (26b) with the internal space of the fuel tank (T).   The said surrounding wall (26b) is integrally formed in the upper part of the said vapor | steam discharge channel | path (26), The said opening part (43) is formed in the upper end of the said surrounding wall (26b), The Claim 1 characterized by the above-mentioned. The fuel supply apparatus as described.   The surrounding wall (26b) and the strainer (27) are covered with a cover member (36) from above, and the cover member (36) is covered with fuel even when the fuel in the fuel tank (T) is full. An unfilled space (36b) is formed, a communication hole (27a) communicating with the space (36b) is formed in the upper portion of the strainer (27), and extends in the vertical direction provided on the side wall of the cover member (36). The fuel supply device according to claim 2, wherein the opening (43) is formed between a slit (36a) and an upper end of the surrounding wall (26b).

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