JP4239085B2 - Fuel pressure regulator - Google Patents

Description

  TECHNICAL FIELD The present invention relates to a fuel pressure adjusting device that adjusts fuel pressure while returning an excess portion of fuel delivered from a fuel pump that is not supplied to an engine together with an in-tank type fuel pump to the inside of the tank. .

  In the fuel supply system, a fuel pump that can handle the maximum fuel flow required for the engine is used, and it is operated so as to keep supplying a constant amount. The surplus fuel generated for this purpose is returned to the fuel tank through the fuel pressure adjusting device. As a place where the fuel pressure adjusting device is installed, for example, as described in Japanese Patent Application Laid-Open No. 9-291863 and Japanese Patent Application Laid-Open No. 11-241659, the fuel pressure adjusting device is installed in a fuel tank. 5 is applied to a so-called non-return type fuel supply system in which the fuel pressure is adjusted by the fuel pressure adjusting device 3B and sent to the injection valve 4 immediately after discharge of the fuel pump 2, as shown in FIG. It can also be applied to the supply system.

  In these fuel supply systems, the fuel pump 2 is immersed in the fuel F of the fuel tank 1, and the fuel pressure adjusting device 3B is installed in the space above the fuel oil level so that the surplus is returned to the fuel oil level as return fuel. It has become.

  Referring to FIG. 6 which is a longitudinal sectional view of the fuel pressure adjusting device 3B, when the return fuel is dropped directly onto the fuel oil level from the valve hole 32b, this flow is generated at the time of idling or low load generating a large amount of return fuel. It tends to be a large and high-speed jet. And when this strong jet collides with the fuel oil level, it generates a loud collision noise, which becomes a loud noise that resonates with the shape and material of the fuel tank and can be heard in the passenger compartment of the automobile, causing discomfort and discomfort to the passengers. May give.

As a countermeasure, instead of the casing 40 provided with the discharge port 40b at the position where the jet flow in FIG. 6 goes straight, as shown in FIG. 7, the fuel pressure adjusting device 3C has an inclined bottom wall 35a on the extension of the injection from the valve hole 32b. As a result, the noise is reduced by causing the jet flow to collide with the inclined bottom wall 35a, decelerating it, and dropping it from the discharge port 35b onto the fuel oil level. Yes. However, even in this case, when the return fuel is large, a loud collision noise is generated when the jet collides with the inclined bottom wall 35a, and the resonance phenomenon may not be prevented depending on the shape and material of the casing 35 with the hopper and the fuel tank. A sufficient noise reduction effect cannot be expected.
JP-A-9-291863 Japanese Patent Laid-Open No. 11-241659

  The present invention is intended to solve the above-described problems, and an object of the present invention is to make it possible to significantly reduce noise generated by a jet of return fuel in an in-tank type fuel pressure adjusting device.

  Therefore, the present invention is arranged in the upper space in the fuel tank in which the fuel pump is installed, adjusts the fuel delivered from the fuel pump to a predetermined pressure, and returns the surplus that is not supplied to the engine as return fuel in the fuel tank. Return fuel that has passed through this valve hole in the spring case bottom through hole formed below the valve hole that opens and closes according to the difference between the pressure of the return fuel and the set pressure of the pressure regulating spring It is assumed that a jet velocity reduction component is installed, in which a diffusion member having a collision surface on which the jet flow collides and is diffused and decelerated, and a porous member that further diffuses and decelerates this diffused return fuel are arranged vertically. .

  Since at least a part of the jet collides with the diffusion member and is diffused, the straightness of the jet part that does not collide is also hindered, and the entire jet is diffused and decelerated. Since it becomes droplets, it is possible to greatly reduce the noise generated when the return fuel jet directly collides with the fuel oil surface.

  In addition, regarding the jet velocity reducing component of the fuel pressure adjusting device described above, if the diffusion member is made of a pair having the same shape and is opposed to the inlet portion of the bottom through hole with a predetermined interval, the two opposing members The jet collides with two diffusion members and diffuses and interferes with each other, thereby exhibiting excellent jet diffusion / deceleration action.

  Furthermore, if this diffusing member has an isosceles triangular end surface and its top edge faces the valve hole, and its collision surface is formed by the top edge and inclined surfaces on both sides thereof, Since the colliding part is largely divided obliquely while being divided into two along the inclination, an excellent deceleration effect can be expected.

  Furthermore, if the collision surface of the diffusing member is formed by a plane perpendicular to the traveling direction of the jet, a further excellent deceleration effect can be expected by diffusing the jet in the horizontal direction. If the collision surface is formed of a spherical surface, the jet flow is complicatedly diffused along the spherical surface, so that a very large deceleration effect can be expected. The diffusion / deceleration effect can be obtained equally by arranging the pair of diffusing members facing each other and by shifting the positions vertically.

  Here, it is assumed that the bottom through-hole is formed by a cylindrical wall projecting upward from the bottom of the spring case, and the jet velocity reduction component is disposed on the periphery of the outlet portion of the bottom through-hole and the frame is formed from the frame. The diffusion member has at least a plurality of legs provided at the upper end portion with locking claws extending upward through the interior of the wall body and engaging with the upper end inlet edge of the cylindrical wall body. It is useful for carrying out the present invention that the projection is formed on one inner surface and the porous member is stretched on the frame.

  That is, this makes it possible to easily attach the jet velocity reducing component to the bottom through hole by retrofitting, and the cylindrical wall body returns fuel diffused by the diffusing member to the outside of the bottom through hole to the bottom of the spring case. It is possible to prevent accumulation and return fuel can be collected in the fuel tank without delay.

  In addition, instead of projecting on the legs, it is possible to reliably diffuse and decelerate the central portion of the jet flow by providing a bridge-like diffusion member that spans multiple legs. If the diffusion member is made of a porous member or a thin plate member and has flexibility, it is possible to bend the upper end portion of the opposing leg, and to the bottom through hole of the jet velocity reduction component It is easy to remove and attach

  If the jet velocity reduction component is a separate product from the spring case, this can be retrofitted to the fuel pressure adjusting device only for a vehicle type that requires noise reduction, which is extremely advantageous in terms of cost.

  According to the present invention, the jet pressure of the return fuel is efficiently diffused and decelerated by providing the fuel pressure adjusting device with the jet velocity reduction component comprising the diffusion member and the porous member in two upper and lower stages. Large noise generated by collision with a surface or the like can be greatly reduced.

  An embodiment of the present invention will be described with reference to the drawings. FIG. 1 shows a longitudinal sectional view of a fuel pressure adjusting device of the present embodiment. This fuel pressure adjusting device 3A is a general in-tank type. The fuel pressure adjusting device is characterized in that a jet velocity reducing component 10A, which is a main part of the present invention, is detachably attached to the bottom through hole 36c of the spring case 36.

  The fuel pressure adjusting device 3A includes a main body 30 having a return line 37 connected from above and having an inside as an inlet chamber 30a, a spring case 36 disposed below the main body 30 and having an inside as an outlet chamber 36a, and a spring case 36. And a casing 35 with a hopper for covering and holding. The hopper-equipped casing 35 has an inclined bottom wall 35a in a region below the bottom through hole 36c, and a discharge port 36b is disposed at a lower portion thereof, and is attached to a fuel tank lid member, a fuel pipe, or the like by a support means (not shown). .

  Inside the inlet chamber 30a, a valve body 31 is fixedly installed in a downward position at the center, and a valve hole opened and closed by the valve body 31 at the center of a diaphragm 32 that partitions the inlet chamber 30a and the outlet chamber 36a. A valve seat 32a having 32b is attached. When the pressure in the inlet chamber 30a due to the return fuel flowing into the inlet chamber 30a through the return pipe 37 becomes higher than the back pressure in the outlet chamber 36a due to the set load of the pressure adjusting spring 36b, the diaphragm 32 moves toward the outlet chamber 36a. Displacement causes the valve seat 32a to be separated from the valve body 31, thereby opening the valve hole 32b and releasing the return fuel from the inlet chamber 30 to the outlet chamber 36a.

  2A is an enlarged vertical cross-sectional view of the jet velocity reduction component 10A of FIG. 1, and FIG. 2B is a perspective view. The jet velocity reduction component 10A has an annular frame 11 having a hole 11a in the center, and extends horizontally from the inner wall surface of the hole 11a toward the center and extends upward, and has a substantially L-shaped side surface. Holding member 10 comprising two legs 12, 12 having a shape, and locking claws 12 a, 12 a projecting from the outer end surfaces of the legs 12, 12, and a net-like porous member stretched on the frame 11 13 and diffusing members 15A and 15A projecting from the inner side surfaces of the legs 12 and 12, respectively.

  The frame 11 is disposed below the valve hole 32b so that the upper surface thereof is in close contact with the peripheral edge on the outlet side of the bottom through hole 36c provided in the spring case 36, and the hole 11a has substantially the same inner diameter as the bottom through hole 36c. And the centers thereof coincide with each other so that the return fuel that has passed through the valve hole 32b passes through as it is. The bottom through hole 36 c is formed by a cylindrical wall body 36 d that protrudes upward from the bottom of the spring case 36.

  The jet velocity reduction component 10A inserts the legs 12 and 12 into the bottom through hole 36c from the lower outlet side, and engages the locking claws 12a and 12a with the upper end inlet edge of the cylindrical wall body 36d, thereby removing the frame 11 from the outlet. It is fixed to the bottom through hole 36c in a state of being in close contact with the side periphery. The holding member 10 is formed of a material such as synthetic resin, and the legs 12 and 12 have elasticity, so that the holding member 10 can be easily detached from the through hole 36c. Further, the diffusing members 15A and 15A are short triangular columnar projections having the same shape of an isosceles end face and are arranged to be opposed to each other with a space therebetween, and the top edges toward the valve holes 32b and on both sides thereof The inclined surface forms a collision surface.

  The fuel pressure adjusting device 3A of the present embodiment is configured as described above, and when the flow of return fuel indicated by the broken line arrow in FIG. 1 becomes a large amount of jet and is jetted downward from the valve hole 32b, this is the bottom portion. It directly collides with the collision surface of the diffusion members 15A and 15A of the jet velocity reduction component 10A mounted in the through hole 36c. Since the diffusion members 15A and 15A are arranged at a distance from each other, the central portion of the jet does not collide with them, but the flow is disturbed by the collision of the impinging jet and the straight flow is prevented, so the entire jet is diffused. And speed is reduced.

  Then, the returned fuel that has been diffused and decelerated is further diffused and decelerated when it passes through the porous member 13 disposed so as to cover the outlet portion of the bottom through hole 36c. As a result, the jet flow passes through the jet velocity reduction component 10A and becomes a state of droplets spreading from the bundle state and falls to the inclined bottom wall 35a of the hopper-equipped casing 35, and the noise caused by the collision is extremely small. Become. The porous member 13 further diffuses and decelerates the diffused and decelerated return fuel, so that even if the eyes are roughened, the object can be sufficiently achieved, and by making the eyes coarse, the resistance is increased and the return fuel is increased. It does not cause the inconvenience that it interferes with the release of water.

  The jet velocity reduction component 10A can be attached to and detached from the bottom wall of the spring case 36. If this is provided as a separate product, it can be attached only to a vehicle type that needs to prevent noise caused by the jet. Therefore, it can be used in common for many types of vehicles equipped with an attachable fuel pressure adjusting device, which is extremely advantageous in terms of cost. Furthermore, even if it is set as the structure which does not provide the casing 35 with a hopper and the return fuel which passed the porous member 13 is dropped directly on a fuel oil surface, the noise prevention effect can fully be anticipated.

  3A to 3F show an embodiment in which the diffusion members 15A and 15A in the jet velocity reduction component 10A described above are diffusion members having different configurations. FIG. 3A shows a jet velocity reducing component 10B in which the heights of the arrangement positions of the diffusion members 15B and 15B having the same shape as the diffusion members 15A and 15A in the above-described embodiment are different from each other. . Thereby, the diffusion direction of the jet is further complicated, and the effect of reducing the jet velocity is good. The same applies to (B) to (D) of FIG. 3 described below, in which the heights of the arrangement positions are different from each other.

  FIGS. 3B and 3C show an embodiment in which the collision surface of the diffusion member is a plane perpendicular to the traveling direction of the jet, and the diffusion members are rectangular parallelepiped diffusion members 15C and 15C. The jet velocity reduction component 10D is shown as the jet velocity reduction component 10C and the diffusion members 15D and 15D having a shape in which a triangular prism having a right triangular shape is turned sideways. In these, the collision surface is a horizontal plane perpendicular to the flow direction of the jet flow, and has an effect of greatly diffusing the jet flow in the lateral direction. FIG. 3D shows a jet velocity reducing component 10E in which the diffusing member is a hemispherical diffusing member 15E, 15E and the collision surface is a spherical surface, and the jet collides with the spherical surface along the curved surface. Since it is diffused in a complicated manner, it is possible to reduce the jet velocity while making the collision sound with the diffusion member extremely small.

  FIGS. 3E and 3F show an embodiment in which the diffusing member is further extended toward the opposite leg and connected to each other so as to be integrated with each other to pass the legs 12, 12. A jet velocity reducing component 10F having a bridge shape as a diffusion member 15F made of a net-like porous member and a jet flow reducing component 10G having a bridge shape as a diffusion member 15G made of a curved thin plate member. Both of these have excellent diffusion and deceleration effects because they directly diffuse the center of the jet. Moreover, if these diffusion members 15F and 15G are made elastic, they can be easily detached from the bottom through hole 36c shown in FIGS.

  As a solution different from the problem solving means using the jet velocity reducing component in the present invention, the steel wool 50 is installed in the outlet chamber 36a so as to close the bottom through hole 36c of the spring case 36 as shown in FIG. As shown in FIG. 9, it is also conceivable that only the net-like porous member 51 is provided alone without providing the diffusion member in the holding member 10. However, in the case of FIG. 8, the trouble that the steel wool 50 bites into the pressure adjusting spring 36b and malfunctions easily occurs. On the other hand, in FIG. 9, if the porous member 51 is fine, the passage resistance becomes too strong and the release of the return fuel is hindered, and the return fuel fills the outlet chamber 36b when idling or low load operation continues for a long time. As a result, there is a concern that the normal function of the fuel pressure adjusting device may be impaired. On the other hand, when the eyes are rough, there is a problem that the jet flow hardly passes through and is not sufficiently decelerated and a noise prevention effect cannot be expected. Therefore, since both have problems, the present invention does not adopt them.

The longitudinal cross-sectional view which shows embodiment of this invention. (A) is an enlarged partial view of FIG. 1, (B) is a perspective view of the jet velocity reduction component of (A). (A)-(F) are the perspective views of the jet velocity reduction components in different embodiment of this invention. Schematic which shows the installation position of a fuel pressure regulator. Schematic which shows the installation position of a fuel pressure regulator. The longitudinal cross-sectional view which shows a prior art example. The longitudinal cross-sectional view which shows a prior art example. The longitudinal cross-sectional view which shows the fuel pressure regulator which employ | adopted a means different from this invention. The longitudinal cross-sectional view which shows the fuel pressure regulator which employ | adopted a means different from this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Fuel tank, 2 Fuel pump, 3A Fuel pressure adjusting device, 10 Holding member, 10A, 10B, 10C, 10D, 10E, 10F, 10G Jet speed reduction parts, 11 Frame, 11a hole, 12 legs, 12a Locking claw, 13 porous member, 15A, 15B, 15C, 15D, 15E, 15F, 15G diffusion member, 32b valve hole, 35 casing with hopper, 35a inclined bottom wall, 35b discharge port, 36 spring case, 36a outlet chamber, 36c bottom through hole 36d Tube wall

Claims (4)

Arranged a fuel pump in the upper space in the fuel tank which is accommodated, falls discharged into the fuel tank of the fuel delivered from the fuel pump as a fuel return a surplus that is not supplied to the engine as well as adjusted to a predetermined pressure, The jet of the return fuel that has passed through the valve hole collides with the bottom through hole provided in the spring case formed below the valve hole that opens and closes according to the difference between the pressure of the return fuel and the set pressure of the pressure adjusting spring. in the fuel pressure regulator jet velocity reducing component formed by arranging a porous member vertically that is attached to the diffusing member further diffusion and deceleration of the return fuel that has diffused with collision surface to be diffused and deceleration Te, said bottom The through hole is formed by a cylindrical wall projecting upward from the bottom of the spring case, and the jet velocity reduction component is a frame disposed on the periphery of the outlet portion of the bottom through hole, and a front side from the frame. A plurality of legs extending upward through the interior of the cylindrical wall body and provided with locking claws at the upper end portion that engage with an upper end inlet edge of the cylindrical wall body, and the diffusion member is the leg at least one projecting from the inner surface, the fuel pressure regulating device porous member is characterized in that it is stretched to the frame. 2. The fuel pressure according to claim 1 , wherein the jet velocity reduction component is provided with a diffusion member bridged over a plurality of the legs instead of projecting the diffusion member on the legs. Adjustment device. The fuel pressure adjusting device according to claim 2 , wherein the bridge-shaped diffusion member is a porous member . The fuel pressure adjusting device according to claim 2 , wherein the bridge-like diffusion member is a thin plate member.