JP2009008168A - Pressure control device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a pressure control device capable of controlling pressure of a fluid with high accuracy while suppressing the manufacturing cost. <P>SOLUTION: An armature 19 and a valve member 30 both include flat abutting faces 27, 31, and the both abutting faces 27, 31 are composed so as to be capable of abutting and separating. A flange part 32 is formed on a valve member 30. A spring 33 for biasing the armature 19 and the valve member 30 in the separating direction is provided between the armature 19 and the flange part 32 of the valve member 30. A ball 29 for swingably supporting the valve member 30 with respect to the movement of the armature 19 is provided between the valve member 30 and a case 10. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a pressure control device that is used in a fuel system of a motorcycle or a four-wheeled vehicle and keeps the pressure of fuel supplied to an internal combustion engine constant.

  Various pressure adjustment mechanisms are used in the fuel systems of motorcycles and four-wheeled vehicles in order to prevent the fuel pressure from becoming excessive. As this pressure adjusting mechanism, a pressure regulator (pressure control device) using a diaphragm is known.

  This pressure regulator is formed by, for example, caulking and joining a case and a cover as shown in Patent Documents 1 and 2, and is a movable valve supported by a diaphragm in a housing having a fuel inlet and outlet. The body is arranged to be movable in the vertical direction. The movable valve body includes an armature (valve main body) in which a flow path for communicating the inflow port and the outflow port is formed, and valve means provided so as to be in contact with and separated from one end side in the armature.

Here, as the valve means, for example, as shown in Patent Document 3, the lower surface of the armature is formed in a tapered shape, and a ball is accommodated in the tapered portion via a spring. Is closed (hereinafter referred to as a taper valve structure). In addition, there is a housing in which a valve plate is provided via a spring and a ball, and the armature flow path is closed by this valve plate. When the pressure of the fuel flowing in the housing exceeds a set value, the armature is pushed upward in accordance with the displacement of the diaphragm, and the armature is detached from the valve means and is opened.
JP 2003-148263 A JP 2003-254200 A JP 2005-163803 A

  However, among the valve means, in the tapered valve structure, the armature is formed in a tapered shape, and the ball is accommodated in the tapered portion. Therefore, the actual valve opening amount with respect to the displacement of the armature is small. There is a problem of being small. That is, if the flow rate increases, the flow rate corresponding to the flow rate cannot be discharged, and there is a problem that the pressure in the housing cannot be kept constant. In addition, a tapered valve such as a ball valve has low wear resistance, and if it wears, the armature cannot be closed reliably, and the accuracy of fuel pressure control is reduced. There is.

  Further, in the case where the armature is closed by the valve plate, the number of parts for providing the valve plate is large, and since it is necessary to perform caulking or brazing at the time of assembly, the number of assembly steps is also large. As a result, there is a problem that the manufacturing cost increases.

  Therefore, the present invention has been made in view of the above-described circumstances, and provides a pressure control device capable of controlling the pressure of a fluid with high accuracy while suppressing the manufacturing cost.

In order to solve the above-mentioned problem, the invention described in claim 1, in a housing having a fluid inlet and outlet, partitions the inside of the housing into an inlet side and an outlet side, A diaphragm that is displaced according to pressure is provided, and the diaphragm includes a valve body in which a flow path that connects the inlet and the outlet is formed, and the pressure of the fluid is provided on the inlet side of the valve body. In the pressure control apparatus provided with valve means for closing or opening the flow path in accordance with the valve body, both the valve body and the valve means have flat surfaces, and both the flat surfaces are configured to contact and separate. The valve means is provided with a holding portion, and an elastic member is provided between the valve main body and the holding portion of the valve means to bias the valve main body and the valve means in a direction away from each other. Together with Between the valve means and the housing, wherein the flexible mechanism for supporting swingably said valve means relative to said housing.
With this configuration, an elastic member that urges the valve body and the valve means to move away from each other is provided, and the elastic member is supported by the holding portion of the valve means. It can be attached without the need for fixing by caulking or brazing. Further, since the flexible mechanism is provided, the valve member can follow the displacement of the valve body. Further, since the valve main body and the valve means are configured to be able to come into contact with and separate from each other on a flat surface, the valve opening amount with respect to the displacement of the diaphragm can be ensured while ensuring the durability of the valve member.

The invention described in claim 2 is characterized in that the flexible mechanism is a ball interposed between the valve means and the housing.
By comprising in this way, a valve | bulb means can be made to follow a motion of a valve main body flexibly by interposing a ball | bowl between a valve | bulb means and a housing.

The invention described in claim 3 is characterized in that the flexible mechanism is a spherical protrusion formed in the housing.
With this configuration, since the spherical protrusion is formed in the housing and the valve means is held by the spherical protrusion, the valve member can flexibly follow the movement of the valve body. .

According to the first aspect of the present invention, the valve means can be mounted without being fixed by caulking, brazing, or the like, so that the number of parts and assembly man-hours can be reduced. Therefore, the manufacturing cost can be reduced.
Furthermore, since the valve opening amount with respect to the displacement of the diaphragm can be ensured, the pressure of the fluid can be stably maintained regardless of the flow rate of the fluid.
According to the third and fourth aspects of the invention, since the valve member can be flexibly followed with respect to the movement of the valve body, even when the valve body is not stable at a low flow rate, the valve body and the valve means The gap can be closed without a gap.

Next, embodiments of the present invention will be described with reference to the drawings. FIG. 1 shows a first embodiment of the present invention.
The pressure regulator (pressure control device) 1 is arranged to be branched in the middle of a fuel supply path through which fuel in a fuel tank (not shown) of the vehicle is pumped to an injector by a fuel pump.

  The pressure regulator 1 includes a housing 5 that is configured by a case 10 and a cover 20 in a substantially cylindrical shape. The case 10 has a concave fuel storage chamber 7, and a fuel inlet 12 is formed on the radially outer side of the bottom wall 11. The inflow port 12 is connected to an oil passage (not shown) that branches off from a fuel supply passage that connects the fuel tank and the injector. A flange portion 13 is formed radially outward on the periphery of the opening of the case 10. The peripheral edge of the annular diaphragm 14 is in contact with the upper surface of the flange portion 13. The diaphragm 14 is made of an elastic material such as rubber.

  A bottomed cylindrical cover 20 is attached to the upper surface of the flange portion 13. A flange portion 16 is formed on the periphery of the opening of the cover 15. The flange portion 16 is caulked so as to be covered with the flange portion 13 of the case 10 with the diaphragm 14 interposed therebetween. Therefore, the outer side in the radial direction of the diaphragm 14 is caulked to the flange portion 16 of the housing 5 by the flange portion 13 of the case 10. Accordingly, the fuel storage chamber 7 is closed by the diaphragm 14, and the inside of the cover 20 and the fuel storage chamber 7 are in a state of being partitioned by the diaphragm 14.

  The end portion (upper wall) 21 of the cover 20 is formed with an outlet 22 that communicates the inside and the outside of the cover 20 at the radial center. The outlet 22 is connected to a fuel tank via a return oil passage (not shown) so that the fuel introduced into the cover 20 is returned to the fuel tank.

  An armature (valve body) 19 is held at the central portion in the radial direction of the diaphragm 14 so as to be interlocked with the diaphragm 14. The armature 19 has a two-stage cylindrical shape, and includes an upper step portion 23 and a lower step portion 24 having a wider diameter than the upper step portion 23. The armature 19 is formed with a flow path 17 penetrating in the axial direction. The flow path 17 communicates the inside of the cover 20 and the fuel storage chamber 7 of the case 10. A boss portion 25 is formed below the lower step portion 24 of the armature 19. The boss portion 25 is formed smaller than the outer diameter of the upper step portion 23 of the armature 19, and the surface thereof is formed flat as a contact surface (flat surface) 27 with a valve member (valve means) 30 described later. Yes.

  The upper stage portion 23 of the armature 19 is inserted through the diaphragm 14. A bracket 26 formed in the shape of a circular dish is fitted and caulked to the upper stage portion 23 of the armature 19 inserted through the diaphragm 14. The bracket 26 is in contact with the lower end of the main spring 43, while the upper end of the main spring 43 is received by the end portion 21 of the cover 20. That is, the main spring 43 applies a reaction force to the cover 20 to urge the diaphragm 14 downward.

  On the other hand, a taper-shaped through hole 28 is formed in the central portion of the case 10 in the radial direction, and a ball (flexible mechanism) 29 is held in the through hole 28. A bottomed cylindrical valve member 30 is fitted over the ball 29 so as to cover it. The valve member 30 has a flat upper surface as a contact surface (flat surface) 31 and is configured to be able to contact and separate from the contact surface 27 of the boss portion 25 in the armature 19. A flange portion (holding portion) 32 extending outward in the radial direction is formed on the periphery of the opening on the lower end side of the valve member 30.

  Here, a spring (elastic member) 33 is provided between the armature 19 and the valve member 30. The spring 33 is mounted so as to surround the boss portion 25 of the armature 19 and the valve member 30, one end of which is in contact with the lower surface of the lower step portion 24 of the armature 19, and the other end is a flange of the valve member 30. It is in contact with the part 32.

  That is, the spring 33 applies a reaction force to the armature 19 to urge the valve member 30 downward. Accordingly, the armature 19 and the valve member 30 are held while being sandwiched between the main spring 43 and the spring 33. The elastic force of the spring 33 is smaller than the elastic force of the main spring 43 provided inside the cover 20, and the flow path 17 of the armature 19 is usually connected to the contact surface 27 of the boss portion 25 and the valve member. The 30 contact surfaces 31 are closed by close contact.

  Specifically, the relationship between the elastic force of the main spring 43 and the elastic force of the spring 33 indicates that when the fuel pressure in the fuel storage chamber 7 is equal to or less than a set value, the elastic force of the main spring 43 is less than that of the spring 33 and the fuel. By exceeding the total pressure, the contact surface 31 of the valve member 30 is in close contact with the contact surface 27 of the boss portion 25 in the armature 19 to close the flow path 17. On the other hand, when the fuel pressure in the fuel storage chamber 7 exceeds the set value, the diaphragm 14 is displaced upward together with the elastic force of the spring 33 so that the armature 19 separates the valve member 30 and opens the flow path 17. It is set to let you. The surplus fuel in the fuel storage chamber 7 is discharged to the return oil passage through the flow path 17 and the inside of the cover 20 and returned to the fuel tank.

  In manufacturing such a pressure regulator 1, first, the ball 29 is disposed in the through hole 28 of the case 10. Then, the valve member 30 is externally fitted so as to cover the ball 29, and the spring 33 is attached to the flange portion 32 of the valve member 30. Then, after the armature 19, the diaphragm 14, the bracket 26, and the main spring 43 are attached in order on the valve member 30, the flange portion 16 of the cover 20 is caulked to the flange portion 13 of the case 10 with the diaphragm 14 interposed therebetween. Thus, the pressure regulator 1 of the present embodiment is completed.

Next, the operation of the pressure regulator 1 will be described.
First, when the fuel in the fuel tank is pumped to the injector through the fuel supply path by driving the fuel pump, the fuel branched from the fuel supply path is placed in the fuel storage chamber 7 of the pressure regulator 1. Will also be introduced. When the pressure of the fuel in the fuel storage chamber 7 is equal to or lower than the set value, the elastic force of the main spring 43 exceeds and the valve member 30 closes the flow path 17 of the armature 19, so that the fuel does not circulate through the pressure regulator 1, It is supplied to the injector with the same pressure.

  In contrast, when the fuel pressure in the fuel storage chamber 7 increases as the fuel pressure in the fuel supply path increases, the sum of the elastic force of the spring 33 exceeds the elastic force of the main spring 43. The diaphragm 14 is displaced upward. When the fuel pressure in the fuel storage chamber 7 exceeds the set value, the armature 19 is separated from the valve member 30 with the displacement of the diaphragm 14 and the flow path 17 is opened.

  Then, surplus fuel in the fuel storage chamber 7 flows into the flow path 17 and is introduced into the cover 20. The fuel introduced into the cover 20 is returned from the outlet 22 of the cover 20 into the fuel tank through the return oil passage. By repeating the above operation, the pressure of the fuel in the fuel supply path is maintained at the set value.

Here, the present inventor compared the control characteristics between the pressure regulator of the present embodiment and the conventional pressure regulator.
FIG. 2 is a graph showing the control pressure with respect to the flow rate. The pressure regulator (A in the drawing) of this embodiment and the lower surface of the armature are formed in a tapered shape as in the conventional case, and the ball is accommodated in the tapered portion. A pressure regulator (B in the figure) having a structure (hereinafter referred to as a taper valve structure) is compared. The control pressure is a set pressure at which the diaphragm is displaced and the armature flow path is opened.

  In the pressure regulator (B in FIG. 2) of the conventional taper valve structure, the change in the control pressure with respect to the change in the flow rate is large, and the gradient is large. And in the high flow area, the control pressure at which the armature flow path is opened increases. This is because the pressure regulator with the taper valve structure has a small actual valve opening amount with respect to the armature displacement, and as the flow rate increases, the corresponding excess fuel cannot be discharged to the cover side. It is considered that the pressure in the housing cannot be kept constant.

  On the other hand, the pressure regulator of the present embodiment has a small change in control pressure with respect to a change in flow rate, and has a smaller gradient than the conventional pressure regulator. In the pressure regulator of this embodiment, the armature and the valve member have flat contact surfaces, and both contact surfaces are configured to be able to contact and separate. Can be secured greatly. As a result, surplus fuel can be reliably discharged to the cover side, so that the fuel pressure can be kept substantially constant even when the flow rate increases.

FIG. 3 is a graph showing the control pressure with respect to the flow rate. In FIG. 3, the pressure regulator of this embodiment (A in FIG. 3) is compared with the pressure regulator without a flexible mechanism (C in FIG. 3). Yes.
It can be seen that the pressure regulator (C in FIG. 3) without the flexible mechanism opens the valve member in the low flow rate region (immediately after the flow rate exceeds 0 in this graph). This is considered that the diaphragm is displaced in the low flow rate region by a slight change (increase) in the pressure in the case. That is, if the diaphragm is displaced before the set value is exceeded, the armature is also displaced, the valve member cannot follow the displacement, and the contact between the contact surfaces of the valve member and the armature is partially Since it is released and the flow path is opened starting from this, the pressure in the fuel storage chamber cannot be kept constant.

  On the other hand, in the pressure regulator of this embodiment, since a ball serving as a flexible mechanism is interposed between the valve member and the housing, even if the armature is not stable in a low flow rate range, the valve member is used for the movement of the armature. Since the swinging state can be flexibly followed, the contact state of each contact surface can be maintained, the flow path can be closed, and the pressure in the fuel storage chamber can be kept substantially constant.

Therefore, according to the above-described embodiment, the spring 33 is provided between the armature 19 and the valve member 30 so as to urge them away from each other, and the spring 33 is brought into contact with the flange portion 32 of the valve member 30. Therefore, the valve member 30 can be held without the need to fix the valve member 30 by caulking, brazing, or the like as in the prior art. Therefore, the number of parts and the number of assembling steps can be reduced, so that the manufacturing cost can be reduced and the degree of design freedom can be improved.
In addition, since the ball 29 is provided between the valve member 30 and the case 10, even if the contact surface 27 of the armature 19 is displaced in the surface direction with respect to a change in fuel pressure in the fuel storage chamber 7. The valve member 30 can be flexibly followed. Therefore, even when the flow rate is low, the flow path 17 of the armature 19 can be closed without gaps.

  Further, since the armature 19 and the valve member 30 are configured to be in contact with and separated from each other at the contact surfaces 27 and 31 formed flat, the durability of the valve member 30 is ensured and the armature 19 is not displaced. The valve opening amount can be secured. As a result, even if the flow rate increases, surplus fuel can be reliably discharged to the cover 20 side and returned to the fuel tank, so that the pressure of the fuel in the fuel storage chamber 7 can be kept substantially constant. it can.

Next, a second embodiment of the present invention will be described. In the present embodiment, the same members as those in the first embodiment are denoted by the same reference numerals, and description thereof is omitted. In this embodiment, the flexible mechanism is different from that of the first embodiment.
As shown in FIG. 3, in the present embodiment, a spherical projection 51 having a substantially spherical shape is formed as a flexible mechanism at the central portion in the radial direction of the case 50. The spherical protrusion 51 is formed by pressing the radial center of the bottom wall 11 of the case 50 from the outside of the case 50. Then, by providing the valve member 30 so as to cover the spherical protrusion 51, the valve member 30 can follow the displacement of the armature 19.

  Therefore, according to the present embodiment, in addition to achieving the same effect as the first embodiment, the ball 29 as in the first embodiment (see FIG. 1) is formed by forming the spherical protrusion 51 on the case 50. ) Is eliminated, the number of parts and the number of assembling steps can be reduced, and the manufacturing cost can be further reduced.

Next, a third embodiment of the present invention will be described. In the present embodiment, the same members as those in the first embodiment are denoted by the same reference numerals, and description thereof is omitted.
As shown in FIG. 4, the valve member 56 of this embodiment is formed by integrally forming the valve means 30 and the ball 29 (both see FIG. 1) of the first embodiment. That is, the valve member 56 has a substantially cylindrical shape, and a substantially hemispherical spherical portion 59 is formed at the center in the radial direction of the lower surface thereof. The spherical portion 59 is held in the through hole 28 of the case 10 to cause the valve member 56 to follow the displacement of the armature 19. The upper surface of the valve member 56 is formed flat as a contact surface 57 with the contact surface 27 formed on the armature 19. A flange 58 extending radially outward is formed on the lower periphery of the valve member 56 and receives one end of the spring 33.

  Therefore, according to the present embodiment, the same effects as those of the first embodiment can be obtained, and the assemblability can be improved because the spherical portion 59 is formed on the lower surface of the valve member 56.

Next, a fourth embodiment of the present invention will be described. In the present embodiment, the same members as those in the first embodiment are denoted by the same reference numerals, and description thereof is omitted. This embodiment is different from the first embodiment in that a valve seat is mounted in the armature.
As shown in FIG. 6, the armature 69 of the present embodiment has a two-stage cylindrical shape, and the inner diameter from the opening of the lower step portion 65 to a part of the upper step portion 64 is formed as a wide diameter portion 67. The inner diameter of the end portion of the portion 64 is formed as a reduced diameter portion 66 that is smaller than the inner diameter of the wide diameter portion 67. A valve seat 68 is press-fitted into the wide diameter portion 67. The valve seat 68 has a cylindrical shape, and has an inner diameter that is substantially the same as that of the reduced diameter portion 66 of the armature. One end of the valve seat 68 is in contact with the reduced diameter portion 66 of the upper step portion 64, and the other end is provided so as to protrude from the lower step portion 65, and the protruding surface becomes the contact surface 70 with the valve member 30. .

  Therefore, according to this embodiment, the same effect as that of the first embodiment can be obtained. In addition, since the armature 69 and the valve member 30 are in intimate contact with each other between flat surfaces, each contact surface must be processed with high accuracy. However, the contact surface 70 on the armature 69 side is a separate valve seat. Since it is comprised by 68, a process can be performed easily. As a result, the manufacturing cost can be reduced.

Next, a fifth embodiment of the present invention will be described. In the present embodiment, the same members as those in the first embodiment are denoted by the same reference numerals, and description thereof is omitted. This embodiment is different from the first embodiment in that a spring is mounted inside the armature.
As shown in FIG. 7, the armature 73 of the present embodiment has a two-stage cylindrical shape, a reduced diameter portion 75 is formed on the upper step portion 74 side, and the lower step portion 76 side is wider than the reduced diameter portion 75. A diameter portion 77 is formed. A spring 78 is mounted in the wide diameter portion 77.

  The valve member 79 has a bottomed cylindrical shape, and the flange portion 32 (see FIG. 1) of the first embodiment is not formed. That is, one end of the spring 78 mounted in the armature 69 is brought into contact with a step portion formed at the boundary between the wide diameter portion 77 and the reduced diameter portion 75, and the other end is brought into contact with the contact surface 31 of the valve member 79. It will be contacted.

  As a result, an elastic force is exerted on the spring 78 between the armature 73 and the valve member 79 to counteract the armature 73 and urge the valve member 79 downward, and the valve member 79 is held. be able to. Therefore, even if the spring 78 is mounted inside the armature 73, the same effect as that of the first embodiment can be obtained.

Next, a sixth embodiment of the present invention will be described. In the present embodiment, the same members as those in the first embodiment are denoted by the same reference numerals, and description thereof is omitted. In the present embodiment, the valve member described above is different from the first embodiment.
As shown in FIG. 8, the valve member 82 of the present embodiment has a cylindrical shape, and a spherical portion 83 is formed at the lower end thereof. The spherical surface portion 83 is held in the through hole 28 of the case 10. An E ring 84 is attached to the valve member 82 so as to surround the periphery thereof. The E-ring 84 serves as a receiver for the spring 33 mounted between the armature 19 and the valve member 82.

  Therefore, according to the above-described embodiment, the same effect as that of the first embodiment is achieved, and the E-ring 84 that receives the spring on the valve member 82 side is provided as a separate body. Therefore, the flange portion 32 as in the first embodiment. (See FIG. 1) need not be formed. Therefore, the manufacturing cost can be reduced, and the degree of freedom in design can be improved by changing the diameter of the E-ring 84.

The present invention is not limited to the above-described embodiment, and includes various modifications made to the above-described embodiment without departing from the spirit of the present invention.
For example, in each of the above-described embodiments, the pressure regulator has been described as being branched from the fuel supply path in which the fuel in the fuel tank of the vehicle is pumped to the injector by the fuel pump. The present invention is not limited and can be applied to various hydraulic circuits.
Furthermore, in the above-described embodiment, the case where the fluid to be pressure-regulated is fuel and the fuel of the vehicle has been described. However, the present invention is not limited to this, and is applicable to water, air, hydraulic circuit hydraulic oil, and the like. be able to.

  Moreover, it is also possible to combine the said embodiment suitably. Further, a leaf spring or the like may be used for each spring.

It is sectional drawing of the pressure regulator in 1st Embodiment of this invention. It is a graph which shows the control pressure with respect to a flow volume. It is a graph which shows the control pressure with respect to a flow volume. It is sectional drawing of the pressure regulator in 2nd Embodiment of this invention. It is sectional drawing of the pressure regulator in 3rd Embodiment of this invention. It is sectional drawing of the pressure regulator in 4th Embodiment of this invention. It is sectional drawing of the pressure regulator in 5th Embodiment of this invention. It is sectional drawing of the pressure regulator in 6th Embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Pressure regulator (pressure control apparatus) 5 Housing 12 Inlet 14 Diaphragm 17 Flow path 19, 69, 73 Armature (valve main body) 27, 31, 57, 70 Contact surface (flat surface) 29 Ball (flexible mechanism) 30, 56, 79, 82 Valve member (valve means) 32, 58 Flange portion (elastic member holding portion) 33, 78 Spring (elastic member) 51 Spherical protrusion (flexible mechanism) 59, 83 Spherical surface portion (flexible mechanism) 84 E-ring (Holding part)

Claims (3)

A housing having an inlet and an outlet for a fluid is provided with a diaphragm that divides the housing into an inlet side and an outlet side, and that is displaced according to the pressure of the fluid. A pressure body provided with a valve body in which a flow path communicating with the outlet is formed, and valve means for closing or opening the flow path according to the pressure of the fluid is provided on the inlet side of the valve body In the control device,
The valve main body and the valve means both have flat surfaces, the two flat surfaces are configured to be able to contact and separate, the valve means is provided with a holding portion, and the valve main body and the valve means are held by the holding means. An elastic member that urges the valve main body and the valve means in a direction to separate them is provided between the parts,
A pressure control device is provided between the valve means and the housing, wherein a flexible mechanism is provided to support the valve means so as to be swingable with respect to the housing.   2. The pressure control device according to claim 1, wherein the flexible mechanism is a ball interposed between the valve means and the housing.   The pressure control apparatus according to claim 1, wherein the flexible mechanism is a spherical protrusion formed on the housing.

Images