JP2012026344A - Pressure adjustment device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a pressure adjustment device capable of suppressing the damage of a diaphragm.SOLUTION: When the fuel pressure of the fuel supply path of a fuel supply system is adjusted to second predetermined pressure by a high-pressure pressure regulator, even if the second predetermined pressure higher than first predetermined pressure being the pressure adjustment value of a low-pressure pressure regulator 10 is applied to the low-pressure pressure regulator 10, a stopper 70 regulates the displacement of a valve element 52 in an opposed seating direction so that the diaphragm 30 is not brought into a stretched state in a radial direction.

Description

  The present invention relates to a diaphragm type pressure adjusting device that adjusts the pressure of a fluid such as fuel supplied from a fuel tank to an internal combustion engine.

  Conventionally, a housing in which a fuel introduction port and a return discharge port are formed, and an outer peripheral portion is caulked and fixed to the housing, and the inside of the housing can be divided into a first chamber and a second chamber facing the introduction port and the return discharge port A flexible diaphragm, a valve body attached to the central portion of the diaphragm, a valve seat formed on the peripheral edge of the return discharge port of the housing and seated on the valve body, and a seating direction in which the valve body is seated on the valve seat There is known a pressure adjusting device including a spring that biases toward a spring.

  When the magnitude of the urging force urged to the diaphragm from the first chamber side by the differential pressure between the first chamber and the second chamber exceeds the magnitude of the urging force in the seating direction by the spring, the valve As the body displaces away from the valve seat and the biasing force from the first chamber side due to the differential pressure increases, the amount of displacement of the valve body in the anti-seat direction increases, and the fuel introduced from the inlet to the first chamber Is discharged from the return discharge port to adjust the pressure in the first chamber (see, for example, Patent Document 1).

JP 2003-278618 A

  However, in the pressure regulator of the prior art, when a high pressure that cannot be regulated is applied to the first chamber, the valve body attached to the central portion of the diaphragm is greatly displaced in the anti-sitting direction. Along with this, there is a problem that the diaphragm is strongly pulled in the radial direction, and the diaphragm itself and the portion fixed by caulking are damaged, which may cause problems such as deterioration of pressure regulation characteristics and deterioration of pressure resistance.

  This invention is made | formed in view of the said point, and aims at providing the pressure regulator which can suppress that a diaphragm receives a damage.

In order to achieve the above object, in the invention described in claim 1,
A housing in which fluid inlets and outlets are formed;
A flexible diaphragm having an outer peripheral portion fixed to the housing and dividing the inside of the housing into a first chamber facing the introduction port and the discharge port and a second chamber different from the first chamber;
A valve body attached to the center of the diaphragm;
A valve seat that is formed at the peripheral edge of the discharge port of the housing and on which the valve body can be seated;
An elastic member that urges the valve body in a seating direction for seating on the valve seat;
When the magnitude of the urging force urged to the diaphragm from the first chamber side by the pressure difference between the first chamber and the second chamber exceeds the urging force in the seating direction by the elastic member, the valve body Is displaced away from the valve seat, and as the biasing force from the first chamber side due to the differential pressure increases, the diaphragm changes the deflection state to increase the amount of displacement of the valve body in the anti-seat direction, and from the inlet A pressure adjusting device that discharges fluid introduced into the first chamber from a discharge port and adjusts the pressure in the first chamber,
The diaphragm includes a displacement restricting member that restricts the displacement of the valve body in the anti-sitting direction so that the diaphragm is maintained in a bent state before being linearly tensioned in the radial direction.

  According to this, the displacement restricting member restricts the displacement of the valve body in the anti-sitting direction, and the diaphragm does not enter a linear tension state in the radial direction. In other words, the diaphragm does not get stuck between the outer peripheral portion fixed to the housing and the central portion to which the valve body is attached. Therefore, damage to the diaphragm can be suppressed.

  The invention according to claim 2 is characterized in that the displacement regulating member is locked to the housing. According to this, since the displacement regulating member can be locked on the housing side instead of the valve body side, it is easy to dispose the displacement regulating member.

  Further, as in the third aspect of the invention, if the displacement regulating member is press-fitted and locked to the housing, it is very easy to dispose the displacement regulating member.

  According to a fourth aspect of the present invention, the displacement regulating member is a cylindrical member extending in the displacement direction of the valve body. When the outer peripheral portion of the diaphragm is fixed to the housing, it is desired that the valve body attached to the central portion of the diaphragm is accurately held at the seating position that serves as a reference for displacement. According to the invention of this claim, it is easy to hold the valve body in the seating position with high accuracy using the internal space of the cylindrical member extending in the displacement direction of the valve body.

  In the invention according to claim 5, the first pressure regulator for adjusting the fuel pressure in the fuel supply path for supplying fuel from the fuel tank to the internal combustion engine to the first predetermined pressure, and the second pressure higher than the first predetermined pressure. In a fuel pressure variable fuel supply system including a second pressure regulator that regulates the pressure to a predetermined pressure, the fuel pressure system is used for the first pressure regulator. According to this, when the fuel pressure in the fuel supply path is regulated to the second predetermined pressure by the second pressure regulator, the second predetermined pressure higher than the first predetermined pressure is applied to the pressure regulator that forms the first pressure regulator. Even when is applied, the displacement regulating member can regulate the displacement of the valve body in the anti-sitting direction so that the diaphragm is maintained in a bent state before the diaphragm is linearly tensioned in the radial direction. Therefore, it is possible to suppress damage to the diaphragm of the pressure adjusting device that forms the first pressure regulator.

It is sectional drawing which shows schematic structure of the low voltage | pressure pressure regulator 10 which is a pressure regulator in one Embodiment to which this invention is applied. 1 is a schematic diagram showing a schematic configuration of a fuel supply system 1 using a low-pressure pressure regulator 10. FIG. 5 is a flowchart for explaining a method of manufacturing the low-pressure pressure regulator 10. FIG. 4 is a graph showing the characteristics of the low pressure regulator 10. In another embodiment, (a) is a top view of the stopper 70A, and (b) is a cross-sectional view of the main part of the low-pressure pressure regulator 10. In another embodiment, (a) is a top view of the stopper 70B, and (b) is a cross-sectional view of the main part of the low-pressure pressure regulator 10. In another embodiment, (a) is a top view of the stopper 70 </ b> C, and (b) is a cross-sectional view of the main part of the low-pressure pressure regulator 10. In another embodiment, (a) is a top view of the stopper 70D, and (b) is a cross-sectional view of the main part of the low-pressure pressure regulator 10. In another embodiment, (a) is a top view of the stopper 70E, and (b) is a cross-sectional view of the main part of the low-pressure pressure regulator 10. It is a schematic diagram which shows schematic structure of the fuel supply system 901 in a comparative example. It is a graph which shows the characteristic of the low voltage | pressure pressure regulator 910 and the high voltage | pressure pressure regulator 9 in a comparative example.

  A plurality of modes for carrying out the present invention will be described below with reference to the drawings. In each embodiment, parts corresponding to the matters described in the preceding embodiment may be denoted by the same reference numerals, and redundant description may be omitted. In the case where only a part of the configuration is described in each embodiment, the other parts of the configuration are the same as those described previously. In addition to the combination of parts specifically described in each embodiment, the embodiments may be partially combined as long as the combination is not particularly troublesome.

(First embodiment)
FIG. 1 is a cross-sectional view showing a schematic configuration of a low-pressure pressure regulator 10 which is a pressure adjusting device in an embodiment to which the present invention is applied, and FIG. 2 is a schematic configuration of a fuel supply system 1 using the low-pressure pressure regulator 10. It is a schematic diagram which shows.

  As shown in FIG. 2, the fuel supply system 1 is a system for supplying fuel stored in a fuel tank 2 to an engine 3 that is an internal combustion engine, and includes a fuel supply path 4, return paths 5 and 6, and a fuel pump. 7, a high-pressure pressure regulator 9, a low-pressure pressure regulator 10, a fuel filter (not shown), and the like.

  The fuel pump 7 is of a motor integrated type including an electric motor unit and an impeller type pump unit driven by the motor unit. The fuel pump 7 sucks and discharges fuel stored in the fuel tank 2 through a suction filter, and pumps the discharged fuel toward the engine 3 through the fuel supply path 4.

  Specifically, the piping that forms the fuel supply path 4 has an upstream end connected to the discharge port of the fuel pump 7 and a downstream end connected to a delivery pipe (not shown), from an injector connected to the delivery pipe. Fuel is supplied to the engine 3.

  The fuel pump 7 includes a DC motor, for example, and can control the rotational speed and the discharge amount proportional to the applied voltage control.

  Return flow paths 5 and 6 are branched and connected to the fuel supply path 4. In this example, the branch connection point of the return flow path 6 is located on the downstream side of the fuel supply path 4 than the branch connection point of the return flow path 5.

  A low pressure regulator 10 corresponding to the first pressure regulator is disposed in the return flow path 5 in the middle of the path. On the other hand, the return flow path 6 is provided with a high pressure regulator 9 corresponding to the second pressure regulator in the middle of the path.

  The low-pressure pressure regulator 10 and the high-pressure pressure regulator 9 are relief valve type pressure-regulating means having the same basic basic configuration except that the pressure-regulating values (pressure-adjusted values) are different. The configuration of the low-pressure pressure regulator 10 and the different configurations of the low-pressure pressure regulator 10 and the high-pressure pressure regulator 9 will be described in detail later.

  In the low-pressure pressure regulator 10, a pressure regulating chamber 21 </ b> A described later forms a part of the return flow path 5 (the pressure regulating chamber 21 </ b> A communicates with the upstream side portion of the return flow path 5 relative to the low-pressure pressure regulator 10). . When the fuel pressure in the pressure regulating chamber 21A communicating with the fuel supply path 4 becomes higher than a predetermined pressure (first predetermined pressure), the valve is opened, and the downstream portion of the return flow path 5 (from the low pressure regulator 10 of the return flow path 5). The pressure is adjusted so that the pressure inside the pressure adjusting chamber 21A becomes the first predetermined pressure. The fuel that has flowed out to the downstream portion of the return flow path 5 returns to the fuel tank 2 (specifically, a jet pump in the fuel tank 2).

  In the high pressure regulator 9, the pressure regulating chamber forms part of the return flow path 6 (the pressure regulating chamber communicates with the upstream side of the return flow path 6 relative to the high pressure pressure regulator 9). When the fuel pressure in the pressure regulating chamber communicating with the fuel supply path 4 becomes higher than a predetermined pressure higher than the first predetermined pressure (second predetermined pressure), the atmospheric pressure in the back pressure chamber and the biasing force of the spring are overcome. The valve body is displaced and opened to allow the fuel to flow out to the downstream portion of the return flow path 6 (portion downstream of the high-pressure pressure regulator 9 of the return flow path 6), so that the pressure regulating chamber becomes the second predetermined pressure. Adjust the pressure so that The fuel that has flowed out to the downstream portion of the return flow path 6 returns to the fuel tank.

  As shown in FIG. 1, the low pressure regulator 10 includes a housing 20, a diaphragm 30, a bush 40, a valve member 50, a spring 60, a stopper 70, and the like.

  The housing 20 forms an outer shell of the low-pressure pressure regulator 10 and includes a first case 21 and a second case 22. The first case 21 is, for example, a cylindrical member made of metal, and the diameter gradually decreases from the second case 22 side (from the upper side in the drawing) in the order of the large diameter portion 211, the medium diameter portion 212, and the small diameter portion 213. ing. On the other hand, the second case 22 is a cup-shaped member that opens downward, for example, made of metal.

  By joining the illustrated upper opening end of the large diameter portion 211 of the first case 21 and the illustrated lower opening end of the second case 22 by winding, the first case 21 and the second case 22 are integrated. The housing 20 is formed. The outer peripheral edge of the diaphragm 30 is sandwiched over the entire circumference at the joint between the first case 21 and the second case 22. Accordingly, the outer periphery of the diaphragm 30 is fixed to the housing 20.

  The diaphragm 30 is made of, for example, rubber (specifically, a rubber sheet member having a base cloth at the center in the thickness direction), and has flexibility. The inner space of the housing 20 is made up of a pressure regulating chamber 21A (corresponding to the first chamber) inside the first case 21 (specifically, inside the large diameter portion 211 and outside a bush 40 described later) by the diaphragm 30. A back pressure chamber 22 </ b> A (a pressure chamber on the back side of the diaphragm 30, corresponding to the second chamber) is partitioned inside the second case 22.

  In the step portion between the large diameter portion 211 and the medium diameter portion 212 of the first case 21, a plurality of introduction ports 214 are opened. By this introduction port 214, the pressure regulating chamber 21A in the housing 20 is always in communication with the fuel supply path 4 described above.

  A bush 40 that is, for example, a metal cylindrical member is press-fitted and fixed inside the middle diameter portion 212 of the first case 21, and an upper portion thereof protrudes into the large diameter portion 211. The upper end opening of the bush 40 is a discharge port 41 for discharging fuel from the pressure regulating chamber 21A. The upper end surface of the bush 40, that is, the peripheral edge portion of the discharge port 41 is a valve seat 42 on which a valve body 52 described later is seated. The bush 40, the inside diameter portion 212 and the inside diameter portion 213 of the first case 21 are fuel passages discharged from the discharge port 41.

  The valve member 50 includes a valve holding part 51, a valve body 52, and a spring receiving part 53, which are all made of metal, for example. The valve holding part 51 is fixed to the through hole formed at the center of the diaphragm 40. A concave portion is formed in the center of the lower surface of the valve holding portion 51, and the alignment ball portion 52a of the valve body 52 is disposed and held in the concave portion. Incidentally, the portion of the valve body 52 that substantially functions as a valve body has a flat plate shape and is integrated with the alignment ball portion 52a. Therefore, the valve body 52 is attached to the center portion of the diaphragm 40.

  A spring receiving portion 53 is caulked and fixed to the outer periphery of a portion of the valve holding portion 51 protruding upward from the diaphragm 30 in the drawing. The spring receiving portion 53 has a flat ring shape with a peripheral edge rising.

  The coiled spring 60 that is an elastic member is accommodated in a compressed state inside the second case 22. The lower end of the spring 60 is in pressure contact with the upper surface of the spring receiving portion 53 of the valve member 50, and the upper end of the spring 60 is in pressure contact with the spring receiving step portion 221 formed on the ceiling surface (upper surface in the drawing) of the second case 22. is doing. Therefore, the spring 60 urges the valve body 52 in the seating direction in which the valve body 52 is seated on the valve seat 42.

  A portion on the inner side of the spring receiving step portion 221 of the second case 22 has a cylindrical shape protruding toward the lower side in the figure, and a press-fit through hole 222 is opened on the inner side. A stopper 70, which is a displacement restricting member that restricts the upward displacement of the valve member 50 in the drawing, is press-fitted and fixed in the press-fitting through hole 222 (press-fitted and locked). The stopper 70 is a metal cylindrical member, for example, and extends in the axial direction of the housing 20, that is, in the displacement direction of the valve member 50.

  A plurality of vent holes 223 are opened in the side wall portion of the second case 22. Due to the plurality of vent holes 223 and the internal passage of the stopper 70, the back pressure chamber 22A in the housing 20 is always in communication with, for example, a space in the fuel tank 2, and the back pressure chamber 22 is almost at atmospheric pressure. Yes.

  In the low pressure regulator 10 having the above-described configuration, the spring 60 has a magnitude of the biasing force that is biased in the counter-sitting direction from the pressure regulating chamber 21A side by the differential pressure between the pressure regulating chamber 21A and the back pressure chamber 22A. When the magnitude of the urging force in the seating direction is exceeded, the valve body 52 is displaced and moves away from the valve seat 42. Then, as the urging force from the pressure regulating chamber 21A due to the pressure difference between the pressure regulating chamber 21A and the back pressure chamber 22A increases, the outer peripheral edge portion fixed to the housing 20 of the diaphragm 30 and the valve member 50 are attached. The valve body 52 increases the amount of displacement in the counter seating direction while changing the bending state of the portion between the central portion and the fuel introduced from the inlet 214 into the pressure regulating chamber 21A is discharged from the outlet 41. Thus, the pressure in the pressure regulating chamber 21A is adjusted.

  The stopper 70 press-fitted and fixed in the press-fitting through hole 222 of the second case 22 has a portion between the outer peripheral edge fixed to the housing 20 of the diaphragm 30 and the central part to which the valve member 50 is attached in the radial direction. The displacement of the valve body 52 in the anti-sitting direction is restricted so as to maintain the bent state before the straight line is tensioned (so that it does not become a tension state).

  The high-pressure pressure regulator 9 changes the pressure adjustment value by changing the set load of the spring 60 with respect to the low-pressure pressure regulator 10. The high-pressure pressure regulator 9 employs the same configuration as the low-pressure pressure regulator 10 except that the set load of the spring 60 is high and the stopper 70 is not provided.

  Here, a manufacturing method of the low pressure regulator 10 will be briefly described.

  First, the first case 21 in which the bush 40 is press-fitted, the diaphragm 30 to which the valve member 50 is attached, and the stopper 70 are temporarily press-fitted (pressed into the upper position in FIG. 1 from the position where the stopper 70 is fixed by main press-fitting described later). ) Prepare the second case 22 and the spring 60. The diaphragm 30 is disposed so that the outer peripheral edge portion is sandwiched between the first case 21 and the second case 22, and the spring 60 is disposed between the second case 22 and the valve member 50.

  Then, a valve member positioning jig is inserted into the upper surface recess of the valve holding portion 51 of the valve member 50 from the outside of the first case 21 through the inside of the cylindrical stopper 70, and the valve body 52 of the valve member 50 is accommodated in the housing. The valve body 52 is securely seated on the valve seat 42 while being disposed on the axis 20 (on the axis of the bush 40). The first case 21 and the second case 22 are wound and fastened while maintaining this state, and the outer peripheral edge portion of the diaphragm 30 is clamped and fixed at this caulking portion. The above is the diaphragm caulking step 110 shown in FIG.

  When the diaphragm caulking step 110 is completed, the spring receiving step portion 221 of the second case 22 is pressed from the upper side of FIG. 1 to be plastically deformed, and the spring 60 is compressed to adjust the set load. Specifically, the low-pressure pressure regulator 10 is attached to a jig (not shown), and the inspection fluid is circulated from the inlet port 214 to the lower outlet of the small-diameter portion 213 of the first case 21 through the outlet port 41. As shown, the compression amount of the spring 60 is adjusted so that the control pressure in the pressure regulating chamber 21A becomes P1 when the return flow rate of the inspection fluid is the first specified flow rate (first predetermined flow rate) Q1. The above is the set load adjustment step 120 shown in FIG.

  When the set load adjustment step 120 is completed, next, the return flow rate of the inspection fluid is increased so that the stopper 70 comes into contact with the upper end portion of the valve member 50 at the second specified flow rate (second predetermined flow rate) Q2. The stopper 70 is fully press-fitted (so that the clearance between the upper end surface of the valve member 50 and the lower end surface of the stopper 70 becomes zero). Specifically, after the return flow rate of the inspection fluid is slightly increased from the second specified flow rate Q2, the stopper 70 is gradually pressed from the temporary press-fitting position, and the return flow rate becomes the second specified flow rate Q2. The press-fitting is stopped to complete the press-fitting. The above is the stopper positioning process 130 shown in FIG.

  When the process up to the stopper positioning process is completed as described above, the low-pressure pressure regulator 10 does not increase the lift amount even when the return flow rate is equal to or higher than the second specified flow rate Q2. A substantially fixed throttle state in which the flow path of the return flow path 5 is narrowed (a state in which the throttle state of the flow path does not change) is defined between the valve seat 42 and the valve seat 42. Incidentally, after the stopper positioning step 130 shown in FIG. 3, the return flow rate of the inspection fluid is increased from the second specified flow rate Q2, and it is detected that the control pressure rises sharply as shown in FIG. You may perform the process of confirming that the above-mentioned fixed aperture state is formed.

  Next, the operation of the fuel supply system 1 including the low pressure regulator 10 will be described based on the above configuration.

  For example, the engine 3 changes from a low load state to a high load state, and a control device (not shown) controls the voltage applied to the fuel pump 7 to change the fuel discharge level of the fuel pump 7 from a low discharge level (first discharge level) to a high discharge level. In the case of the level (second discharge level where the discharge amount is larger than the first discharge level), the fuel flows from the fuel supply path 4 into the return flow path 5 and returns to the fuel tank 2 via the low pressure regulator 10. The fuel flow rate (return flow rate) increases. When the return flow rate exceeds the second specified flow rate (second predetermined flow rate) described above, the space between the valve body 52 and the valve seat 42 of the low-pressure pressure regulator 10 is in the fixed throttle state described above. The return flow rate is limited by the flow resistance of the substantially fixed throttle portion, and the low-pressure pressure regulator 10 stops functioning.

  The fuel discharged from the fuel pump 7 flows through the fuel supply path 4 and partly flows into the return flow path 6 and is regulated by the high-pressure pressure regulator 9. That is, the fuel pressure in the fuel supply path 4 becomes the second predetermined pressure described above, and the high fuel pressure control state is established. At this time, a control device (not shown) controls the injection drive pulse width of the injector for high fuel pressure (second predetermined pressure) corresponding to a high engine load.

  Further, for example, when the engine 3 changes from a high load state to a low load state, and a control device (not shown) controls the voltage applied to the fuel pump 7 to change the fuel discharge level of the fuel pump 7 from the high discharge level to the low discharge level. In this case, the fuel pressure in the fuel supply path 4 becomes lower than the control pressure of the high pressure regulator 9, and the high pressure regulator 9 stops functioning. When the flow rate of the fuel flowing through the return flow path 5 becomes equal to or less than the second specified flow rate (second predetermined flow rate) described above, the low-pressure pressure regulator 10 recovers its function.

  A part of the fuel discharged from the fuel pump 7 flows into the return flow path 5 and is regulated by the low-pressure pressure regulator 10. That is, the fuel pressure in the fuel supply path 4 becomes the first predetermined pressure described above, and the low fuel pressure control state is set. At this time, the control device (not shown) controls the injection drive pulse width of the injector for low fuel pressure (first predetermined pressure) corresponding to the low load of the engine.

  According to the above-described configuration and operation, when the fuel pressure in the fuel supply path 4 of the fuel supply system 1 is adjusted to the second predetermined pressure by the high-pressure pressure regulator 9, the low-pressure pressure regulator 10 applies the first predetermined pressure. A high second predetermined pressure is applied, but the stopper 70 restricts the displacement of the valve body 52 in the anti-sitting direction so that the diaphragm 30 is not pulled in the radial direction. Therefore, the diaphragm 30 of the low pressure regulator 10 can be prevented from being damaged.

  Further, when the fuel pressure in the fuel supply path 4 is shifted from the first predetermined pressure to the second predetermined pressure, the gap between the valve body 52 and the valve seat 42 of the low pressure pressure regulator 10 is a predetermined value corresponding to the second specified flow rate Q2. The throttle state is fixed, and the first predetermined pressure can be accurately transferred to the second predetermined pressure.

  FIG. 10 is a schematic diagram showing a schematic configuration of a fuel supply system 901 of a comparative example. As shown in FIG. 10, the fuel supply system 901 is provided with an orifice 911 on the downstream side of the low-pressure pressure regulator 910 that does not have the stopper 70 with respect to the low-pressure pressure regulator 10. In the fuel supply system 901 having such a configuration, when the transition from the low fuel pressure to the high fuel pressure is performed using the pressure loss of the orifice 911 which is a fixed throttle, as shown in FIG. If the performance is varied, the flow rate of the fuel flowing through the return flow path 5 when the fuel pressure rises sharply varies. That is, the variation in the inner diameter of the orifice 911 becomes the variation in the timing of shifting to the high fuel pressure between the fuel supply systems 901.

  On the other hand, according to this embodiment, the restriction position of the displacement of the valve body 52 of the low-pressure pressure regulator 10 is determined based on the second specified flow rate Q2. In other words, each low-pressure pressure regulator 10 has a function equivalent to a fixed throttle, and the fuel flow rate that flows through the return flow path 5 when the fuel pressure rises steeply is the same for each low-pressure pressure regulator 10. 2 The flow rate is adjusted to be a specified flow rate Q2. Therefore, according to the fuel supply system 1 employing the low-pressure pressure regulator 10 of the present embodiment, the timing for shifting to a high fuel pressure can be made uniform.

  The stopper 70 is press-fitted from the outside into the second case 21 of the housing 20 and locked. Therefore, it is very easy to dispose the stopper 70 at a predetermined position corresponding to the return flow rate.

  The stopper 70 is a cylindrical tubular member. Therefore, when the diaphragm caulking step 110 is executed, the valve member positioning jig or the like can be inserted into the stopper 70 so that the valve member 50 can be accurately held at a predetermined position.

(Other embodiments)
The preferred embodiments of the present invention have been described above, but the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the spirit of the present invention.

  In the above embodiment, the stopper 70 has a cylindrical shape, but is not limited thereto. For example, a cylindrical stopper 70A as shown in FIG. 5A may be press-fitted into the press-fitting through hole 222 and fixed as shown in FIG. 5B. Alternatively, a stopper 70B having a polygonal column shape (here, a hexagonal column shape) as shown in FIG. 6A may be press-fitted into the press-fitting through hole 222 and fixed as shown in FIG. 6B.

  The stopper is not limited to the one fixed to the housing 20 by press-fitting. For example, a stopper 70C made of a screw member as shown in FIG. 7A is replaced with a female screw through hole 222A as shown in FIG. 7B. It may be fixed by screwing in.

  Further, the stopper is not limited to the one fixed to the housing 20 side, and may be one fixed to the valve member 50 side. For example, a stopper 70D made of a screw member as shown in FIG. 8A may be fixed by screwing into a female screw portion of the valve holding portion 51 of the valve member 50 as shown in FIG. 8B. . Moreover, the stopper 70E which consists of a screw member as shown to Fig.9 (a) may be screwed and fixed to the external thread part of the valve holding part 51 of the valve member 50, as shown in FIG.9 (b). .

  In FIGS. 5 to 9, (b) shows a cross-sectional view of the main part of the low-pressure pressure regulator 10, and (a) shows a top view of each stopper 70 </ b> A to 70 </ b> E corresponding to the displacement regulating member.

  Further, the stopper that is the displacement restricting member is not limited to one that is separate from the housing 20. For example, a part of the second case 22 may be formed by plastic deformation.

  In the above embodiment, as shown in FIG. 2, in the fuel supply system 1, the portion other than the downstream side portion of the fuel supply path 4 is disposed in the fuel tank 2, but is not limited thereto. It is not a thing. For example, some or all of the components constituting the fuel supply system 1 may be mounted outside the fuel tank. Moreover, each structure may be modularized integrally, and each may be a different body.

  Moreover, although the said embodiment demonstrated the case where the pressure regulator to which this invention was applied was employ | adopted as the low voltage | pressure pressure regulator 10 of the fuel supply system 1 which varies a fuel pressure, it is not limited to this. For example, the present invention may be applied to a pressure regulator of a fuel supply system that adjusts the fuel pressure to a single pressure and supplies the fuel pressure from the fuel tank to the internal combustion engine. According to this, even if the fuel is cut by the injector while the fuel is being pumped by the fuel pump and the fuel pressure in the fuel supply path temporarily becomes a high pressure that cannot be controlled by the pressure regulator, the diaphragm of the pressure regulator It is possible to suppress receiving damage.

DESCRIPTION OF SYMBOLS 1 Fuel supply system 2 Fuel tank 3 Engine (internal combustion engine)
4 Fuel supply path 9 High pressure regulator (second pressure regulator)
10 Low pressure regulator (first pressure regulator, pressure regulator)
20 Housing 21A Pressure adjusting chamber (first chamber)
22A Back pressure chamber (2nd chamber)
30 Diaphragm 41 Discharge port 42 Valve seat 52 Valve body 60 Spring (elastic member, biasing member)
70, 70A, 70B, 70C, 70D, 70E Stopper (displacement regulating member)
214 Inlet

Claims (5)

A housing in which fluid inlets and outlets are formed;
A flexible diaphragm that has an outer peripheral portion fixed to the housing, and divides the inside of the housing into a first chamber facing the introduction port and the discharge port, and a second chamber different from the first chamber;
A valve body attached to the center of the diaphragm;
A valve seat formed on a peripheral portion of the discharge port of the housing, and the valve body being separable;
An elastic member that urges the valve body in a seating direction for seating on the valve seat;
The magnitude of the urging force urged by the diaphragm from the first chamber side due to the differential pressure between the first chamber and the second chamber exceeds the magnitude of the urging force in the seating direction by the elastic member. When the valve body is displaced and separated from the valve seat, and the urging force from the first chamber side due to the differential pressure increases, the diaphragm changes its bending state, and the valve body is anti-seat seated. A pressure adjusting device that adjusts the pressure in the first chamber by increasing the amount of displacement in the direction and discharging the fluid introduced from the inlet to the first chamber through the outlet;
A pressure adjusting device comprising: a displacement regulating member that regulates displacement of the valve body in the anti-sitting direction so that the diaphragm is maintained in a bent state before being linearly tensioned in the radial direction.   The pressure adjusting device according to claim 1, wherein the displacement regulating member is locked to the housing.   The pressure adjusting device according to claim 2, wherein the displacement regulating member is press-fitted and locked to the housing.   The pressure regulating device according to claim 2, wherein the displacement regulating member is a cylindrical member extending in a displacement direction of the valve body.   A first pressure regulator for adjusting a fuel pressure in a fuel supply path for supplying fuel from the fuel tank to the internal combustion engine to a first predetermined pressure; and a second pressure regulator for adjusting a second predetermined pressure higher than the first predetermined pressure; 5. The pressure regulator according to claim 1, wherein the pressure regulator is used for the first pressure regulator.

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