JP4264363B2 - Fuel pressure regulating valve - Google Patents

Description

  The present invention relates to a pressure adjustment valve suitable for a fuel pressure adjustment valve that is disposed in a fuel supply system and adjusts the pressure of a fuel supply passage, for example.

  Fuel supply pipes for automobiles and motorcycles are pipes that connect a fuel pump that pumps fuel stored in a fuel tank and a fuel injection valve that supplies fuel to a combustion chamber. In the middle of the pipe, there is disposed a fuel pressure adjusting valve for releasing a part of the fuel and returning it to the fuel tank when the pressure of the supplied fuel exceeds a predetermined value.

  As such a pressure regulating valve, for example, in Patent Document 1 below, a high pressure is connected to a fuel supply passage between a fuel pump and a fuel injection valve and communicates with the fuel supply passage by returning surplus fuel to the fuel tank. A housing defining a chamber, a low pressure chamber communicating with the fuel tank, a bush having a pressure release passage communicating the high pressure chamber and the low pressure chamber, and an upstream end of the bush so as to be separable And a valve member, wherein the bush has a plurality of communication passages that block the release pressure passage and branch and connect the cutoff upstream side and the cutoff downstream side. A fuel pressure regulating valve having an isostatic partition wall is disclosed.

  However, in such a conventional fuel pressure regulating valve, the fuel flow-in occurs at the time of a hot restart when the engine ambient temperature has greatly increased (a state where the engine is operated for a certain period of time and then stopped and then the engine is started again). The fuel in the pump and the pump part of the fuel pump and the casing is heated to generate vapor, and this vapor causes a fuel lock phenomenon in the fuel inflow path, the pump part, the casing, etc., and stable fuel supply can be achieved. Sometimes it disappeared.

For this reason, in Patent Document 2 below, a fuel distribution path is formed in a fuel injection device for a motorcycle in which fuel boosted by a fuel pump is supplied via a fuel injection valve in an intake pipe connected to the engine. And a fuel distribution pipe provided with a fuel injection valve, a fuel chamber disposed at a lower position in the gravity direction of the fuel tank and integrally formed at an upper position in the gravity direction of the fuel distribution pipe, and the fuel A fuel pump that is disposed in the chamber and discharges the fuel in the fuel chamber after being boosted; and a pressure regulating valve that adjusts the fuel pressure in the fuel distribution pipe to a constant pressure and is integrally attached to the fuel distribution pipe or the fuel chamber; A fuel inflow passage for supplying the fuel in the fuel tank into the fuel chamber, a fuel return passage connecting the pressure regulating valve and the fuel chamber, a discharge passage of the fuel pump, and a fuel distribution passage A fuel discharge passage which communicates, motorcycle fuel injection apparatus characterized by comprising a vapor vent passage communicating with said fuel chamber and the fuel tank is disclosed. According to this apparatus, the vapor generated in the fuel chamber is returned to the fuel tank through the vapor extraction passage, so that the fuel can be stably supplied at the time of hot restart or the like.
JP 2003-278618 A JP 11-141438 A

  However, in the technique described in Patent Document 2, the fuel in the fuel tank is supplied to the fuel inflow chamber via the fuel inflow passage, and the fuel is supplied from the fuel chamber to the fuel distribution passage via the fuel discharge passage. Since it is necessary to provide a vapor passage in the fuel chamber and return the vapor to the fuel tank, the structure is complicated.

  Accordingly, an object of the present invention is to provide a fuel pressure regulating valve that can maintain a constant supply pressure of a fluid and also allow vapor generated in the fluid to escape.

  In order to achieve the above object, according to a first aspect of the present invention, there is provided a fuel pressure regulating valve that opens and closes by sensing a fluid pressure, a valve housing that is connected in communication with a fluid flow path to regulate the pressure, and the fluid flow A valve body disposed in the valve housing so as to open and close a flow path passing through the valve housing from a path, and the valve body as a small-diameter valve body that opens the communication portion with a first pressure; A large-diameter valve body that opens the communication portion with a second pressure larger than that, and a flow path that passes through the valve housing includes a small-diameter portion provided on the fluid flow path side, and the small-diameter portion. The large-diameter valve body has a large-diameter portion that is inwardly expanded and has a large-diameter portion, and the large-diameter valve body has a large-diameter passage that passes through the valve housing via a large-diameter spring. Arranged so as to seal the large-diameter portion by being pressed against the portion, the small-diameter valve body is A small-diameter spring is inserted into a passage penetrating the large-diameter valve body so that the tip of the small-diameter portion is pressed against the small-diameter portion of the flow path passing through the valve housing to seal the small-diameter portion. A fuel pressure regulating valve is provided.

  According to the above invention, when the pressure in the fluid flow path rises, when the relatively small first pressure is exceeded, the small-diameter valve body is opened first, and the pressure rises further, and the larger pressure is reached. When the pressure of 2 is exceeded, the large-diameter valve body opens. For this reason, the vapor generated in the fluid has a small flow resistance, so that when the small-diameter valve body is opened, the vapor can pass through most of the valve housing and escape from the fluid flow path. When the pressure in the fluid flow path exceeds the second pressure, the large-diameter valve body opens, so that a large amount of fluid can pass through the valve housing and escape from the fluid flow path. The fluid pressure supplied through the fluid flow path can be kept constant. In a state between the first pressure and the second pressure, part of the fluid escapes through the opening of the small diameter valve body together with the vapor, but the opening of the small diameter valve body is relatively Since it is small, the pressure of the supplied fluid does not fluctuate greatly.

  Accordingly, it is possible to supply the fluid at a predetermined pressure by escaping the vapor generated in the flow path without providing another device for escaping the vapor only by providing the pressure regulating valve. For this reason, when applied to, for example, a fuel pressure control valve, fuel can be stably supplied during hot restart or the like.

  And by providing a small diameter part and a large diameter part in the passage in the housing, it becomes possible to arrange the small diameter valve body and the large diameter valve body on the same passage, and to make the valve body compact. In addition, only by using a material such as rubber having a high sealing performance only for the contact surface between the small diameter valve element and the small diameter portion of the housing, the sealing performance when the fluid pressure is lower than the first pressure is achieved. Can be increased.

  According to a second aspect of the present invention, there is provided the fuel pressure regulating valve according to the first aspect, wherein a rubber seal cap is attached only to the small diameter valve element.

  According to the present invention, when a relatively small first pressure is exceeded, a small-diameter valve body is opened first, and when the pressure further increases and exceeds a second pressure larger than that, a large-diameter valve body is opened. Therefore, the vapor generated in the flow path can be released and fluid can be supplied at a predetermined pressure without providing another device for releasing the vapor. For this reason, when applied to, for example, a fuel pressure control valve, fuel can be stably supplied during hot restart or the like.

  1 to 11 show an embodiment of a fuel pressure regulating valve according to the present invention.

  As shown in FIG. 1, the fuel pressure regulating valve 10 has a valve housing 11 and a connector 12 that connects the valve housing 11 to a fluid passage that will be described later.

  As shown in FIG. 2, the valve housing 11 has a cylindrical portion 13, a flange portion 14 formed on the outer periphery of one end surface thereof, and a bulging portion 15 formed on one side of the flange portion 14. ing. The cylindrical portion 13 is formed with a communication hole 16 on the end surface on the flange portion 14 side, and the inner side of the communication hole 16 has an inner periphery of the cylindrical portion 13 via a slightly enlarged diameter portion 16a and a tapered portion 16b. To the surface. The end surface opposite to the communication hole 16 forms an opening 17 into which a valve body and the like to be described later are inserted. A female screw 18 is formed on the inner periphery of the cylindrical portion 13. Furthermore, an opening 19 is formed at the end face of the bulging portion 15, and the opening 19 communicates with the internal space 21 of the cylindrical portion 13 through the passage 20. The flange portion 14 has a shape protruding in a pair of opposing directions, and an insertion hole 23 of a bolt 22 fastened to the connector 12 is formed in the protruding portion. A seal ring groove 30 having a gourd shape is formed on the end face of the flange portion 14 so as to surround the communication hole 16 and the opening portion 19, and a seal ring 31 is mounted in the seal ring groove 30. .

  As shown in FIG. 3, the connector 12 includes an introduction pipe portion 24 connected to a fluid flow path, which will be described later, an arm portion 25 projecting in a pair of opposing directions around the introduction pipe portion 24, and an introduction pipe And a discharge pipe portion 26 extending in a direction orthogonal to the portion 24. A male screw is formed on the outer periphery of the introduction pipe part 24 and is screwed to a pipe part constituting a fluid flow path to be described later. At both ends of the arm portion 25, screw holes 27 into which the bolts 22 are screwed are formed. Therefore, the end surface of the flange portion 14 of the valve housing 11 and the end surface of the arm portion 25 of the connector 12 are joined to each other via the seal ring 31, and the bolt 22 is passed through the hole 23 of the flange portion 14 to the screw hole 27. By tightening and fixing, the valve housing 11 and the connector 12 are hermetically joined. An introduction hole 28 communicating with the communication hole 16 of the valve housing 11 is formed in the introduction pipe portion 24. Further, a return passage 29 is formed in the discharge pipe portion 26 so that one end opens to the end face of the discharge pipe portion 26 and the other end communicates with the opening portion 19 of the valve housing 11.

  A small-diameter valve body 32, a small-diameter spring 33, a large-diameter valve body 34, a large-diameter spring 35, and a screw cap 37 are inserted into the cylindrical portion 13 of the valve housing 11 through the opening 17. It has become.

  As shown in FIG. 4, the large-diameter valve body 34 extends in the axial direction from a small-diameter cylindrical portion 38, an enlarged-diameter cylindrical portion 39, a radial connecting wall 40 that connects them, and an outer end of the connecting wall 40. The dividing wall portion 41, the slit 42 formed between the connecting wall 40 and the dividing wall portion 41, and the rear end portion of the dividing wall portion 41 are annularly formed so as to form the end face of the enlarged diameter cylindrical portion 39. It has the cylinder end part 39a connected. A tapered sealing surface 43 is formed on the outer periphery of the front end of the small-diameter cylindrical portion 38, and this sealing surface 43 comes into contact with and separates from the tapered portion 16b (see FIG. 2C) of the valve housing 11 so that the valve It can be opened and closed. The rear end surface of the small-diameter cylindrical portion 38 is closed by a bottom wall 44, and a boss portion 45 formed by a bulging wall is formed at the inner peripheral center of the bottom wall 44. A hole 46 is formed.

  The small-diameter valve body 32 includes a valve main body 47 and a rubber seal cap 48 attached to the front end surface of the valve main body 47. As shown in FIG. 5, the valve main body 47 has an outer diameter cylindrical portion 49 adapted to the inner periphery of the enlarged diameter cylindrical portion 39 of the large-diameter valve body 34 and a front end surface of the cylindrical portion 49 closed. The projection 50 has a smaller diameter than the projection 50 and an annular rib 51 formed on the outer periphery of the projection 50. As shown in FIG. 6, the seal cap 48 has a shape that covers the outer periphery of the protrusion 50, and has an annular groove 52 that fits the annular rib 51 on the inner periphery thereof. Further, on the outer periphery of the front end surface of the seal cap 48, a tapered seal surface 53 is formed so as to be in contact with and away from the inner periphery of the corner portion of the communication hole 16 of the valve housing 11 and the slightly enlarged diameter portion 16a.

  As shown in FIG. 7, the screw cap 37 has a male screw 54 on the outer periphery that is screwed into the female screw 18 of the valve housing 13. An annular recess 55 into which the rear end portion of the large diameter spring 35 is inserted is formed on the front end surface. Further, a slit-like groove 56 for inserting and rotating a flathead screwdriver or the like is formed on the rear end surface. Further, a seal ring groove 57 in which the seal ring 36 (see FIG. 1) is mounted is formed on the outer periphery of the rear end.

  1 and 8 together, the small-diameter valve body 32 is inserted into the inner periphery of the small-diameter cylindrical portion 38 of the large-diameter valve body 34 through the small-diameter spring 33. In this case, the rear end of the small diameter spring 33 is fitted to the outer periphery of the boss portion 45. Although the small-diameter valve body 32 is accommodated in the large-diameter valve body 34, the seal surface 53 directly contacts and separates from the inner periphery of the communication hole 16 of the valve housing 11 to open and close the communication hole 16. Yes.

  The large-diameter valve body 34 is inserted into the internal space 21 of the valve housing 11 while accommodating the small-diameter valve body 32 on the inner periphery thereof. The large-diameter spring 35 disposed at the rear end portion of the large-diameter valve body 34 is pressed at its rear end portion by a screw cap 37, and the seal surface 43 of the large-diameter valve body 34 is pressed against the valve housing by a predetermined pressing force. 11 taper portions 16b. By adjusting the screwing amount of the screwing cap 37, the fluid pressure at which the large-diameter valve body 34 opens can be set accurately.

Next, the operation of the pressure regulating valve 10 will be described with reference to FIGS.
As shown in FIG. 8, the pressure regulating valve 10 is configured such that a male screw of the introduction pipe portion 24 of the connector 12 is screwed into a female screw hole 62 formed in the middle of a fuel supply pipe 60 of, for example, an automobile or a two-wheeled automobile. And connected to the fuel supply pipe 60. As a result, the flow path 61 of the fuel supply pipe 60 communicates with the communication hole 16 of the valve housing 11 through the introduction hole 28 of the connector 12. The discharge pipe portion 26 of the pressure regulating valve 10 is connected to a return pipe to a fuel tank (not shown).

  In the state shown in FIG. 8, the fluid pressure in the fuel supply pipe 60 is equal to or lower than the first pressure A (see FIG. 11, 120 KPa in this embodiment), and the large-diameter spring 35 seals the large-diameter valve body 34. The surface 43 is pressed against the tapered portion 16 b of the valve housing 11, and the seal surface 53 of the small diameter valve body 32 is pressed against the inner periphery of the communication hole 16 of the valve housing 11 by the small diameter spring 33. For this reason, the fluid in the fuel supply pipe 60 does not flow into the valve housing 11. At this time, since the small diameter valve body 32 seals the communication hole 16 with the rubber seal cap 48, the sealing performance is good and the passage of fuel can be completely blocked. Further, since the rubber seal cap 48 may be relatively small, the material cost can be reduced.

  In the state shown in FIG. 9, the fluid pressure in the fuel supply pipe 60 exceeds the first pressure A, but is below the second pressure B (see FIG. 11, 210 KPa in this embodiment). The large-diameter valve body 34 pressed by the diameter spring 35 does not open, but the small-diameter valve body 32 pressed by the small-diameter spring 33 opens. Therefore, part of the fuel in the fuel supply pipe 60 passes through the communication hole 16, passes through the gap 72 between the small diameter valve body 32 and the small diameter cylindrical portion 38 of the large diameter valve body 34, and further passes through the small hole 46. Then, it flows into the large-diameter valve body 34, passes through the slit 42, passes through the passage 20 and the return passage 29, and is returned to the fuel tank via a return pipe (not shown). However, even if the small-diameter valve body 32 is opened, the passage formed thereby is relatively narrow, so that a large amount of fuel is not returned into the fuel tank. However, the fuel vapor generated in the fuel supply pipe 60 at the time of hot restart or the like has a small flow resistance, so that most of the fuel vapor passes through a narrow passage formed when the small-diameter valve body 32 is opened. Released to the fuel tank. As a result, fuel can be stably supplied during hot restart or the like.

  Further, in this state, the fuel is returned to the fuel tank through the small hole 46. Therefore, by changing the size of the small hole 46, the gradient between A and B in FIG. can do.

  In the state shown in FIG. 10, the fluid pressure in the fuel supply pipe 60 exceeds the second pressure B (see FIG. 11, 210 KPa in this embodiment), and the large-diameter valve element 34 that is in pressure contact with the large-diameter spring 35. Is also open. Therefore, a part of the fuel in the fuel supply pipe 60 passes through the communication hole 16, the diameter-expanded portion 16 a, the internal space 21 of the valve housing 11, the passage 20, and the return passage 29, and a return pipe (not shown). Is returned to the fuel tank. Since the passage formed at this time is relatively wide, surplus fuel is quickly supplied to the fuel tank according to the opening amount of the large-diameter valve body 34, in other words, according to the fluid pressure in the fuel supply pipe 60. It is possible to escape. Therefore, when the engine is in operation, for example, a stable fuel supply can be performed in the range of region C in FIG. The fuel pressure D when the engine is operating is set to 220 to 240 KPa, for example.

  The sealing surface 43 of the large-diameter valve body 34 is a plastic molding surface instead of rubber. However, when the large-diameter valve body 34 is opened, the small-diameter valve body 32 is already open, and the large-diameter valve body 34 is opened. When the small-diameter valve body 32 is also closed, the small-diameter valve body 32 is hermetically sealed as described above, so that there is no problem in terms of sealing performance. As a result, the amount of expensive sealing material such as rubber can be reduced, and the cost can be reduced.

  FIG. 12 shows a reference example of the fuel pressure regulating valve according to the present invention. It should be noted that substantially the same parts as those of the above-described embodiment are denoted by the same reference numerals and description thereof is omitted.

  In the embodiment, the small diameter valve element 32 is accommodated in the large diameter valve element 34, but the seal surface 53 directly contacts and separates from the inner periphery of the communication hole 16 of the valve housing 11 to open and close the communication hole 16. The structure to be adopted is adopted.

  On the other hand, in this reference example, the small-diameter valve element 32 is completely accommodated in the large-diameter valve element 34 via the small-diameter spring 33, and is contacted and separated from the communication hole 70 provided in the large-diameter valve element 34. The communication hole 70 of the large-diameter valve body 34 is configured to open and close. The direct opening / closing of the valve housing 11 with respect to the communication hole 16 is performed only by the large-diameter valve body 34. A sealing material 71 having a good sealing property such as rubber is mounted on the sealing surface of the large-diameter valve body 34. In this embodiment, the small-diameter valve body 32 is also provided with a seal cap 48 made of a material having good sealing properties such as rubber. However, the main body of the small-diameter valve body 32 is not used without using the seal cap 48. You may make it seal by contact | abutting directly.

  Also in this fuel pressure adjusting valve, when the fluid pressure in the fuel supply pipe 60 exceeds the first pressure A but is equal to or lower than the second pressure B, the large diameter pressed by the large diameter spring 35 is used. Although the valve body 34 is not opened, the small diameter valve body 32 pressed by the small diameter spring 33 is opened. When the fluid pressure in the fuel supply pipe 60 exceeds the second pressure B, the large-diameter valve body 34 that is pressed by the large-diameter spring 35 is also opened. Therefore, the same operations and effects as those of the above embodiment can be obtained. Moreover, in this embodiment, since the small diameter valve body 32 and the large diameter valve body 34 can be assembled | attached previously and integrated, the advantage that an assembly operation becomes easy is acquired.

  INDUSTRIAL APPLICABILITY The present invention can be used in a system that is arranged in a fluid supply path and adjusts and supplies a fluid pressure. For example, a fuel pressure adjustment valve that is arranged in a fuel supply system and adjusts the pressure of a fuel supply passage It can be suitably used.

It is a disassembled perspective view which shows one Embodiment of the pressure regulation valve of this invention. The valve housing of the pressure control valve is shown, (a) is a front view, (b) is a bottom view, and (c) is a side sectional view. The connector of the pressure control valve is shown, (a) is a plan view, (b) is a front view, and (c) is a side sectional view. The large diameter valve body of the same pressure regulation valve is shown, (a) is a front view, (b) is a side view, (c) is a sectional view along the line AA. The valve main body of the small diameter valve body of the same pressure control valve is shown, (a) is a side view, (b) is a side sectional view. The seal cap of the small diameter valve body of the same pressure control valve is shown, (a) is a side view, (b) is a side sectional view. The screw cap of the same pressure regulating valve is shown, (a) is a front view, (b) is a side sectional view. It is explanatory drawing which shows the operating state below the 1st pressure in the same pressure regulation valve. It is explanatory drawing which shows the operation state more than the 1st pressure and below the 2nd pressure in the same pressure regulation valve. It is explanatory drawing which shows the operating state more than the 2nd pressure in the same pressure regulation valve. It is a graph which shows the relationship between the fluid pressure and fluid flow rate in the same pressure regulation valve. It is explanatory drawing which shows other embodiment of the fuel pressure control valve by this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Pressure regulating valve 11 Valve housing 12 Connector 16 Communication hole 20 Passage 21 Inner space 24 Connection pipe part 28 Introduction hole 32 Small diameter valve body 33 Small diameter spring 34 Large diameter valve body 35 Large diameter spring 37 Screw cap 38 Small diameter cylindrical part 39 Large diameter Cylindrical portion 42 Slit 43 Seal surface 46 Small hole 47 Valve body 48 Seal cap 53 Seal surface 70 Communication hole 71 Seal material A First pressure B Second pressure

Claims (2)

In the fuel pressure adjustment valve that opens and closes by sensing fluid pressure,
A valve housing attached in communication with a fluid flow path whose pressure is to be adjusted, and a valve body disposed in the valve housing so as to open and close a flow path passing through the valve housing from the fluid flow path. Prepared,
As the valve body, it has a small-diameter valve body that opens the communication portion with a first pressure, and a large-diameter valve body that opens the communication portion with a second pressure larger than that,
The flow path that passes through the valve housing has a small diameter portion provided on the fluid flow path side, and a large diameter portion that is inward and larger in diameter than the small diameter portion,
The large-diameter valve body is disposed so that the distal end portion thereof is in pressure contact with the large-diameter portion of the flow path passing through the valve housing and seals the large-diameter portion via a large-diameter spring,
The small-diameter valve body seals the small-diameter portion by pressure-contacting the small-diameter portion of the flow path passing through the valve housing through a small-diameter spring in a passage passing through the large-diameter valve body. The fuel pressure regulating valve is arranged so as to   The fuel pressure regulating valve according to claim 1, wherein a rubber seal cap is attached only to the small-diameter valve body.

Images