JP2008144651A - Pressure control valve and fuel supply pump - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a pressure control valve capable of reducing hysteresis without requiring guide by an outer circumference of a spring even if a sealing ball is used. <P>SOLUTION: In a pressure control valve provided with a valve holder, the sealing ball, a piston, and the spring, the piston can reciprocate in an axial direction by energizing force of the spring and a pressure in a high pressure part side to close an exhaust pressure port when pressure at the high pressure part gets to predetermined value or less, and to open the exhaust port and release pressure in the high pressure part by moving with resisting the energizing force of the spring when pressure in the high pressure part exceeds the predetermined value, an a spring seat including an outer circumference part corresponding to an inner circumference surface of a first cylindrical space part, a spring guide part defining a radial direction position of a spring, and a ball seat part on which the sealing ball is seated between the spring and the sealing ball. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a pressure control valve and a fuel supply pump, and in particular, a pressure control attached to a fuel supply pump, a pressure accumulator (common rail), and other pressure devices in a fuel injection system of an internal combustion engine such as a gasoline engine or a diesel engine. The present invention relates to a valve and a fuel supply pump including such a pressure regulating valve.

  2. Description of the Related Art Conventionally, in a fuel injection system for an internal combustion engine, a pressure control valve is attached to a fuel supply pump, a common rail, and the like for the purpose of adjusting the pressure and flow rate of the fuel. An outline of the pressure control valve attached to the fuel injection system will be described with reference to FIGS. 10 and 11.

FIG. 10 is a cross-sectional view showing an example of a conventional pressure control valve. In the pressure control valve 350, a piston 352 is slidably accommodated in a cylinder 351, and the piston 352 is elastically urged toward a pressure receiving port 351A of the cylinder 351 by an elastic urging mechanism 353. An overflow port 351B that is opened and closed by a piston 352 is formed on the side wall of the cylinder 351. Then, the piston 352 moves according to the fuel pressure in the pipe 382 connected to the pressure receiving port 351A, and when the overflow port 351B is opened, the fuel in the pipe 352 is released to the drain pipe 383 through the overflow port 351B. Thus, an operation for maintaining the fuel pressure on the fuel inlet side of the control valve (not shown) at a predetermined pressure is performed (see, for example, Patent Document 1).
In the pressure control valve 350 shown in FIG. 10, a fixing bolt 360 is used as a member for sealing the opening of the cylinder 351 opposite to the pressure receiving port 351A, and a shim 361 is used to adjust the setting force of the spring 353. It arrange | positions and the approach degree of the fixing bolt 360 is adjusted.

  Compared to a structure using a fixing bolt and shim, the cost can be reduced and the setting force of the spring can be easily performed. Therefore, a spherical seal member is used instead of the fixing bolt and shim. There is a pressure control valve. More specifically, as shown in FIG. 11, a valve holder 321, a valve seat 322, a valve body 323, a spring seat 324, a valve spring 325, a sealing ball 326, and a filter 327 are provided. The pressure relief valve 320 includes a sealing ball 326 that seals the inside of the valve holder 321 and can adjust the urging force of the valve spring 325 according to the press-fitting position (see, for example, Patent Document 2). . That is, by employing a sealing ball as the sealing member, it is easy to process, and it is possible to easily adjust the urging force of the valve spring and ensure the sealing performance.

JP 2005-188432 A (paragraphs [0011] to [0019], all drawings) JP 2002-13653 A (paragraphs [0019] to [0020], FIG. 1)

However, in the case of a pressure control valve having a configuration using a sealing ball as described in Patent Document 2, it is necessary to guide on the outer periphery of the spring in order to prevent the spring from collapsing. For this reason, there is a possibility that hysteresis increases due to friction between the spring and the inner surface of the valve body.
In particular, in recent years, the pressure of injected fuel has been increased for the purpose of improving the combustion state in the cylinders of internal combustion engines, reducing pollutants contained in exhaust gas, and reducing noise and vibration. There is a tendency to set a large spring set force in the pressure control valve. Therefore, an increase in hysteresis due to the fall of the spring appears remarkably, and there is a possibility that the function of the pressure control valve cannot be stabilized.

Accordingly, the inventors of the present invention have made diligent efforts to dispose such a problem by arranging a predetermined spring seat between the sealing ball and the spring in the pressure control valve provided with the sealing ball. The present invention has been completed by finding out that the problem can be solved.
That is, an object of the present invention is to provide a pressure control valve that can reduce hysteresis without the need to guide the outer periphery of a spring even when a sealing ball is used.

  According to the present invention, a spring accommodating portion and a cylinder portion are provided, a first cylindrical space portion is formed in the spring accommodating portion, a second cylindrical space portion is formed in the cylinder portion, and the first cylindrical space portion is formed. And a valve holder in which the second cylindrical space portion communicates in the axial direction and both ends are opened, a sealing ball which is press-fitted from the open end on the first cylindrical space portion side and seals the open end, A pressure control valve comprising: a piston slidably disposed in the cylindrical space part 2; and a spring accommodated in the first cylindrical space part and sandwiched between the sealing ball and the piston, The open end of the second cylindrical space portion is desired on the high-pressure portion side, and the cylinder portion of the valve holder is provided with an exhaust pressure port that communicates with the high-pressure portion side as the piston moves. With axial pressure The pressure relief port is closed when the pressure in the high pressure part is below a predetermined value, and moves against the biasing force of the spring when the pressure in the high pressure part exceeds the predetermined value. The pressure in the high-pressure part can be released by communication, and the outer peripheral part corresponding to the inner peripheral surface of the first cylindrical space part and the radial position of the spring are defined between the spring and the sealing ball. A pressure control valve in which a spring seat having a spring guide portion and a ball seat portion on which a sealing ball is seated is provided, and the above-described problems can be solved.

  In the pressure control valve of the present invention, it is preferable that the spring guide portion is a protrusion having an outer diameter that matches the inner diameter of the spring.

  In the pressure control valve of the present invention, it is preferable that the outer peripheral portion is a cylindrical portion that protrudes in the axial direction from the circumferential edge portion of the spring seat.

  In the pressure control valve of the present invention, it is preferable that the cylindrical portion as the outer peripheral portion and the protrusion as the spring guide portion protrude in opposite directions along the axial direction.

  In the pressure control valve of the present invention, it is preferable that the cylindrical portion protrudes on the sealing ball side and that a gap be provided between the cylindrical portion and the sealing ball.

  Another aspect of the present invention includes a spring accommodating portion and a cylinder portion, a first cylindrical space portion is formed in the spring accommodating portion, a second cylindrical space portion is formed in the cylinder portion, and the first The cylindrical space portion and the second cylindrical space portion communicate with each other in the axial direction and are opened at both ends, and are sealed from the opening end on the first cylindrical space portion side to seal the open end A pressure control valve comprising: a ball; a piston slidably disposed in the second cylindrical space; and a spring accommodated in the first cylindrical space and sandwiched between the sealing ball and the piston. An open end of the second cylindrical space portion of the pressure control valve is desired on the high pressure portion side, and the cylinder portion of the valve holder communicates with the high pressure portion side as the piston moves. It has an exhaust port and the piston When the pulling urging force and the pressure on the high-pressure part can reciprocate in the axial direction, the pressure relief port is closed when the pressure on the high-pressure part is below the specified value, and the pressure on the high-pressure part exceeds the specified value It moves against the urging force of the spring and communicates with the exhaust pressure port so that the pressure in the high pressure part can be released, and the inner peripheral surface of the first cylindrical space part between the spring and the sealing ball A fuel supply pump, comprising: a spring seat having an outer peripheral portion corresponding to the above, a spring guide portion defining a radial position of the spring, and a ball seat portion on which a sealing ball is seated. is there.

  According to the pressure control valve of the present invention, by disposing a predetermined spring seat between the sealing ball and the spring, it becomes difficult for the spring to collapse, so that it is not necessary to guide the outer periphery of the spring. Therefore, even when the setting force of the spring is increased in order to adjust the pressure medium to a higher pressure, an increase in hysteresis due to the fall of the spring can be prevented. As a result, the pressure control of the pressure medium can be performed stably.

  Further, in the pressure control valve of the present invention, by providing a predetermined protrusion as the spring guide portion, there is no need to guide the outer periphery of the spring, so that the outer diameter of the spring has a margin with respect to the inner diameter of the spring accommodating portion. be able to. Therefore, even in a state where the spring contracts and expands in the circumferential direction, the outer periphery of the spring is not pressed against the inner peripheral surface of the spring accommodating portion, and an increase in hysteresis can be reduced.

  In the pressure control valve of the present invention, by providing the predetermined cylindrical portion as the outer peripheral portion, the contact area between the outer peripheral portion and the first cylindrical space portion is increased, and the spring seat can be stabilized.

  Further, in the pressure control valve of the present invention, when the spring seat is assembled by providing the projecting portion as the spring guide portion and the cylindrical portion as the outer peripheral portion on the opposite side in the axial direction, Can be discovered quickly and misassembly can be prevented.

  Further, in the pressure control valve of the present invention, when the cylindrical portion as the outer peripheral portion protrudes on the sealing ball side, the sealing ball has a gap between the cylindrical portion and the sealing ball. When press-fitting or when a large spring force is applied to the spring, the cylindrical portion can be prevented from being bitten between the sealing ball and the valve holder.

  Further, according to the fuel supply pump of the present invention, since the pressure control valve having a predetermined structure is provided, an increase in hysteresis due to the fall of the spring is reduced, and the supplied fuel flow rate can be stably controlled. .

Hereinafter, the fuel injection system including the pressure control valve of this embodiment and the fuel supply pump provided with the pressure control valve will be specifically described with reference to the drawings as appropriate. However, this embodiment shows one aspect of the present invention and does not limit the present invention, and can be arbitrarily changed within the scope of the present invention.
In addition, in each figure, what has attached | subjected the same code | symbol has shown the same member, and description is abbreviate | omitted suitably.

[First Embodiment]
The first embodiment includes a spring accommodating portion and a cylinder portion, a first cylindrical space portion is formed in the spring accommodating portion, a second cylindrical space portion is formed in the cylinder portion, and the first cylinder is formed. A valve holder in which the space portion and the second cylindrical space portion communicate in the axial direction and both ends are opened; a sealing ball that is press-fitted from the opening end on the first cylindrical space portion side and seals the open end; The pressure control valve includes a piston slidably disposed in the second cylindrical space, and a spring accommodated in the first cylindrical space and sandwiched between the sealing ball and the piston. .
In the pressure control valve of the present embodiment, the open end of the second cylindrical space portion is desired on the high pressure portion side, and the cylinder portion of the valve holder is provided with an exhaust pressure port communicating with the high pressure portion side as the piston moves. The piston can be reciprocated in the axial direction by the biasing force of the spring and the pressure on the high-pressure part side, and when the pressure of the high-pressure part is below a predetermined value, the exhaust port is closed and the pressure of the high-pressure part reaches a predetermined value. When it exceeds, it moves against the urging force of the spring, and the pressure relief port communicates to release the pressure in the high pressure part. Between the spring and the sealing ball, the first cylindrical space part A spring seat having an outer peripheral portion corresponding to the inner peripheral surface, a spring guide portion that defines a radial position of the spring, and a ball seat portion on which a sealing ball is seated is arranged.

A pressure control valve 10 according to this embodiment will be described with reference to FIG. FIG. 1 shows a cross-sectional view of the pressure control valve 10 connected to the fuel pipe 16.
The pressure control valve 10 includes a valve holder 20, a sealing ball 30, a spring seat 60, a spring 50, and a piston 40. The valve holder 20 includes a spring accommodating portion 20a having a first cylindrical space portion 21 inside and a cylinder portion 20b having a second cylindrical space portion 22 inside. The first cylindrical space portion 21 and the second cylindrical space portion 22 communicate with each other in the axial direction, and are open at both ends. Among the opening ends on both sides, the opening end on the cylinder part 20b side is arranged to face the high pressure part side H, and is configured as a pressure receiving port 20A. Further, a back pressure port 25 for removing the back pressure of the piston 40 is provided in the spring accommodating portion 20 a of the valve holder 20.

  Further, the sealing ball 30 and the spring 50 are accommodated in the first cylindrical space portion 21 of the spring accommodating portion 20a. Among these, the sealing ball 30 is press-fitted from the opening end 20B on the spring accommodating portion 20a side, whereby the first cylindrical space portion 21 of the valve holder 20 is closed. Further, the setting force of the spring 50 can be adjusted by adjusting the pushing amount of the sealing ball 30. If the member for sealing the first cylindrical space 21 is such a sealing ball 30, the manufacturing cost can be suppressed without requiring complicated processing, and the setting force of the spring 50 can be reduced. Adjustment can be performed easily.

  A piston 40 is slidably accommodated in the second cylindrical space portion 22 of the cylinder portion 20b, and the piston 40 is biased toward the pressure receiving port 20A of the cylinder portion 20b by the biasing force of the spring 50. Has been. The piston 40 is provided with a step 41 for restricting the radial movement of the spring 50. The outer diameter of the step 41 is the same as the inner diameter of the spring 50, the movement of the spring 50 in the radial direction is restricted, and an increase in hysteresis due to the fall of the spring 50 can be prevented.

  Further, the exhaust port 23 that is opened and closed by the piston 40 is formed in the side wall portion of the cylinder portion 20b. The piston 40 is a hollow body, and when the fuel pressure of the pressure receiving port 20A exceeds a predetermined value defined by the set force of the spring 50, the exhaust pressure port 23 communicates with the hollow portion 40a of the piston 40. A communication hole 41 is provided. Further, a circumferential groove 24 is formed on the inner peripheral surface of the cylinder portion 22 so as to overlap the exhaust pressure port 23. By providing such a circumferential groove 24, regardless of the rotational position of the piston 40, the communication hole 41 overlaps with any part of the circumferential groove 24 of the valve holder 20 and exhausts pressure from the exhaust pressure port 23. be able to.

The pressure receiving port 20A, the exhaust pressure port 23 and the circumferential groove 24 of the valve holder 20 and the communication hole 41 of the piston 40 respond to the fuel pressure in the fuel pipe 16 connected to the pressure receiving port 20A. When the communication hole 41 of the 40 and the exhaust pressure port 23 communicate with each other, the fuel in the pipe 16 is released to the drain pipe 18 through the hollow portion 40a and the exhaust pressure port 23, whereby a high pressure pump (not shown). An operation for maintaining the fuel pressure on the fuel inlet side at a predetermined pressure is performed.
That is, when the fuel pressure of the pressure receiving port 20A exceeds a predetermined value, the exhaust pressure port 23 blocked by the outer peripheral surface of the piston 40 is released, and the fuel from the fuel pipe 16 is released to the drain pipe 18 and the pressure receiving port Reduce the fuel pressure of 20A. When the fuel pressure decreases in this way, the exhaust pressure port 23 is again blocked by the outer peripheral surface of the piston 40 that is moved by the urging force of the spring 50, and the fuel pressure increases. Thus, the piston 40 is positioned in response to the fuel pressure of the pressure receiving port 20A, and the pressure of the fuel pressure of the pressure receiving port 20A is adjusted to a predetermined level by opening and closing the exhaust pressure port 23.

  In the pressure control valve 10, the spring seat 60 interposed between the sealing ball 30 and the spring 50 corresponds to the inner peripheral surface of the first cylindrical space 21 and has a minute clearance (not shown). The outer peripheral part 63 arrange | positioned so that may be formed, the spring guide part 61 which prescribes | regulates the radial direction position of the spring 50, and the ball seat part 62 on which the sealing ball | bowl 30 is seated. By interposing such a spring seat 60, the radial movement of the spring seat 60 itself is restricted by the outer peripheral portion 63, and the radial movement of the spring 50 is restricted by the spring guide portion 61. Can be prevented. Therefore, even when the setting force of the spring is increased in order to control the fuel pressure to a high pressure, the hysteresis is reduced and the pressure control can be stably performed.

A spring seat 60 provided in the pressure control valve 10 shown in FIG. 1 is shown in FIG. FIG. 2A shows a perspective view of the spring seat 60 viewed from the sealing ball side, and FIG. 2B shows a perspective view of the spring seat 60 viewed from the spring side.
In the example of the spring seat 60, the spring guide portion 61 is configured by a protrusion 61 </ b> A having an outer diameter that matches the inner diameter of the spring 50, and the outer peripheral portion 63 is from a circumferential edge 60 e of the spring seat 60. It is comprised from the cylindrical part 63A which protrudes toward the ball | bowl for sealing along an axial direction. That is, the projecting portion 61A and the cylindrical portion 63A project in opposite directions along the axial direction.

  The spring guide portion 61 formed of such a protrusion 61A can be supported without providing an extra clearance between the spring 50 and the guide portion, so that rattling of the spring can be eliminated. Increase in hysteresis can be prevented. Further, in the case of the spring guide portion 61 including the predetermined protrusion 61A, it is not necessary to guide the outer periphery of the spring 50, and the outer diameter of the spring 50 can be given a margin with respect to the inner diameter of the spring accommodating portion 20a. . Therefore, even when the spring 50 contracts, the outer periphery of the spring 50 does not come into contact with the inner peripheral surface of the spring accommodating portion 20a even when the spring 50 is in a state of spreading in the circumferential direction. Therefore, it is possible to prevent an increase in hysteresis due to strong pressing.

  Moreover, since the axial direction length of the outer peripheral part 63 can be lengthened by comprising the outer peripheral part 63 as the cylindrical part 63A, the inner peripheral surface of the first cylindrical space part of the spring seat 60 and the valve holder The contact area can be increased. Therefore, the inclination of the spring seat 60 itself can be prevented, the spring seat surface 65 of the spring seat 60 can be maintained in a direction orthogonal to the axial direction, and the fall of the spring can be made difficult to occur.

  Further, in this example of the spring seat 60, the protrusion 61A as the spring guide portion 61 and the cylindrical portion 63A as the outer peripheral portion 63 protrude in the opposite directions along the axial direction. When assembling, it is possible to prevent the spring seat from being assembled with the axial direction being wrong.

  Further, the spring seat 60 shown in FIG. 2 has a hole 60A formed in the axial center portion, and a taper is formed on the edge 67 on the sealing ball side of the hole 60A, and the sealing ball is sheeted. It is configured as a ball seat portion 62A. With the ball sheet portion 62A using such a taper, the sealing ball 30 is sheeted on the surface, so that the spring seat 60 can be stabilized. Further, since no corners are left on the edge 67 of the hole 60A, it is possible to avoid the corners from being cut and the metal pieces from being mixed inside.

Further, while the sealing ball and the spring sheet are seated in the ball sheet portion, as shown in FIG. 3, the cylindrical portion 63A protruding from the sealing ball 30 and the sealing ball 30 are in contact with each other. It is preferable to have a gap S. By providing such a gap S, when the sealing ball 30 is press-fitted or when the spring force of the spring is greatly applied, the cylindrical portion 63 </ b> A is formed in the first cylindrical space portion 21 of the valve holder 20. It can be prevented between being pinched between the inner peripheral surface and the sealing ball 30 and being bitten.
FIG. 3 is an enlarged cross-sectional view of a range surrounded by A in FIG.

The configuration of the spring seat is not limited to that shown in FIG. 2, and the spring seat can be configured as shown in FIGS. 4 to 6.
The spring seat 60 ′ shown in FIG. 4 has an outer peripheral portion 63 composed of a cylindrical portion 63B protruding from the circumferential edge 60e along the axial direction toward the spring 50, and an inner peripheral surface of the outer peripheral portion 61. Functions as a guide portion 61 </ b> C that restricts the radial movement of the spring 50. Also, a hole 60A is formed in the axial center portion of the spring seat 60 ′, and the edge of the hole 60A on the sealing ball 30 side is formed in a taper shape to constitute a ball sheet portion 62B.

  Further, the spring seat 60 ″ shown in FIG. 5 coincides with the inner diameter of the spring 50 and the outer peripheral portion 63 composed of the cylindrical portion 63 </ b> C projecting toward the spring 50 side along the axial direction from the circumferential edge 60 e. And a spring guide portion 61 composed of a protrusion 61C having a large outer diameter. Further, a hole 60A is formed in the axial center portion of the spring seat 60 ', and the edge of the hole 60A on the sealing ball 30 side is formed in a taper shape to constitute a ball sheet portion 62C.

  6A to 6B show a spring seat 70a in which a hole is not provided in the axial center portion, a recess 68 is provided on the surface on the sealing ball side, and an edge 62D thereof is configured as a ball seat portion 62. 70b, FIG. 6 (a) is a spring seat 70a deformed based on the spring seat 60 of FIG. 1, and FIG. 6 (b) is based on the spring seat 60 'of FIG. This is a deformed spring seat 70b.

  Any of the spring seats 60 ′, 60 ″, 70 a, 70 b shown in FIGS. 4 to 6 is stably arranged with respect to the sealing ball 30 by the ball seat portion 62, and the valve The inclination of the spring seats 60 ′ and 60 ″ itself can be prevented by the outer peripheral portion 63 disposed through a minute clearance with respect to the inner peripheral surface of the first cylindrical space portion 21 of the holder 20. Further, the radial movement of the spring 50 can be restricted by the spring guide portion 61. Therefore, even when the setting force of the spring 50 is increased in order to control the fuel pressure to a high pressure, the inclination of the spring 50 can be prevented and the hysteresis can be reduced.

[Second Embodiment]
The second embodiment is a fuel injection system for an internal combustion engine including a fuel supply pump provided with the pressure control valve of the first embodiment.
FIG. 7 shows a schematic diagram of a configuration example of the fuel injection system of the present embodiment. The fuel injection system 100 includes a common rail 101, a high-pressure pump 102 that supplies high-pressure fuel to the common rail 101, and a low-pressure pump 103 that pumps fuel to the high-pressure pump 102.

In the fuel injection system 100, the fuel F in the fuel tank 105 is pressurized by the low-pressure pump 103 and supplied to the high-pressure pump 102 as described later.
A fuel supply path 106 having a filter 104 is provided between the fuel inlet side port 103 A of the low pressure pump 103 and the fuel tank 105, and fuel from which dust or the like has been removed by the filter 104 passes through the fuel supply path 106. Thus, the configuration is sent to the low-pressure pump 103. Further, a fuel supply path for supplying low-pressure fuel supplied from the low-pressure pump 103 to the high-pressure pump 102 between the outlet port 103B on the fuel outlet side of the low-pressure pump 103 and the suction port 102A of the high-pressure pump 102. 108 is arranged. The fuel supply path 108 is configured using a filter 109 for removing dust in the fuel sent from the low pressure pump 103 and a proportional solenoid valve for controlling the flow rate of the low pressure fuel supplied to the high pressure pump 102. The low-pressure fuel whose flow rate is controlled by the flow rate control valve 107 is supplied from the suction port 102A of the high-pressure pump 102 into the cylinder chamber 102B via the check valve 111. It has become. The flow control valve 107 is controlled by a control unit (not shown), and the flow rate of the low-pressure fuel is controlled so that the rail pressure in the common rail 101 becomes a given target rail pressure.

  In addition, a pressure control valve 110 is connected to the fuel supply path 108 for the purpose of maintaining the pressure of the low-pressure fuel on the fuel inlet side of the flow control valve 107 at a predetermined value. In the fuel injection system 100 shown in FIG. 7, a pressure receiving port 110 </ b> A of the pressure control valve 110 is connected to the fuel supply path 108 between the filter 109 and the flow control valve 107 by a pipe 112. When the pressure of the low pressure fuel at the pressure receiving port 110A exceeds a predetermined level, the pressure control valve 110 causes the low pressure fuel to overflow from the exhaust pressure port 110B, whereby the pressure of the low pressure fuel on the inlet side of the flow control valve 107 is It is configured to operate so as to be maintained at a substantially predetermined constant pressure. The overflow low-pressure fuel from the exhaust pressure port 110 </ b> B is returned to the fuel tank 105 through the drain pipe 113.

  Further, the pressure regulating valve 110 further has a take-out port 110C for taking out the fuel sent from the low-pressure pump 103 to the pressure receiving port 110A as lubricating oil, and the fuel taken out from the take-out port 110C is appropriately selected. The fuel is fed into the cam chamber 102C of the high-pressure pump 102 through the lubricating oil line 115 having the orifice means 114 having the structure described above, and this fuel serves as lubricating oil.

  In the fuel injection system of this embodiment, the pressure adjustment valve described in the first embodiment is used as the pressure adjustment valve 110. Since this pressure adjustment valve can reduce the increase in hysteresis due to the fall of the spring that biases the piston, stable control can be achieved even when the spring pressure is increased to increase the fuel pressure. can do. As a result, it is possible to precisely control the pressure of the fuel injected from the injector, thereby reducing noise and reducing pollutants contained in the exhaust gas discharged from the internal combustion engine.

  In the example of the fuel injection system 100 shown in FIG. 7, the low pressure pump 103, the fuel supply path 108, the flow rate control valve 107, the pressure control valve 110, and the high pressure pump 102 are provided in one fuel supply pump 120. It has become. However, it is not essential to configure all the members integrally, and some or all of them can be provided as separate members.

As an example of the present invention, the pressure control valve 10 provided with a spring seat shown in FIGS. 1 and 4 was attached to a fuel pipe through which high-pressure fuel flows, and the hysteresis generated when pressure control was performed was measured. . This measurement was performed by adjusting the spring set force so that when the fuel pressure reached 5 bar, fuel at a flow rate of 300 L / h was discharged from the discharge port.
FIG. 8A shows the relationship between the fuel pressure in the fuel pipe and the flow rate of the fuel discharged from the discharge port when the pressure control valve 10 of FIG. 1 is used, and FIG. FIG. 5 shows the relationship between the fuel pressure in the fuel pipe and the flow rate of fuel discharged from the discharge port when the pressure control valve 10 of FIG. 4 is used.

  On the other hand, as a comparative example of the present invention, the pressure control valve 210 without a spring seat shown in FIG. 9 was used, pressure control was performed under the same conditions as those described above, and the resulting hysteresis was measured. . FIG. 8C shows the relationship between the fuel pressure in the fuel pipe measured at that time and the flow rate of the fuel discharged from the discharge port.

  As shown in FIGS. 8A to 8C, in the pressure regulating valve 210 (pressure control valve in FIG. 9) that does not include a spring seat and directly suppresses the end of the spring with a sealing ball. The hysteresis generated when the pressure in the fuel pipe is 5 bar shows a large value of 140 L / h (see FIG. 8C). On the other hand, if the pressure control valve 10 having the predetermined spring seat according to the present invention (the pressure control valve in FIGS. 1 and 4), the hysteresis generated when the pressure in the fuel pipe is 5 bar is 30 L / h. Compared to the pressure control valve 210 having no spring seat, the hysteresis is reduced to about 1/5 (see FIGS. 8A and 8B).

  In addition, the hysteresis measurement using each pressure control valve was repeated 6 times, and the resulting variation in hysteresis was measured. As a result, in the case of the pressure regulating valve 210 having no spring seat shown in FIG. The maximum variation in the size was 20.3 L / h. On the other hand, in the case of the pressure control valve 10 having the spring seat according to the present invention shown in FIG. 1 and FIG. 4, the hysteresis variation was within the maximum range of 3.3 L / h. From this result, it is understood that it is effective to provide a spring seat.

As described above, according to the pressure control valve of the present invention, in the pressure control valve using the sealing ball, by disposing a predetermined spring seat between the sealing ball and the spring, a higher pressure can be achieved. Even when the control is performed, an increase in hysteresis due to the fall of the spring is prevented, and the pressure can be controlled stably.
Therefore, in addition to the fuel injection system as described above, it can be suitably employed as a valve for controlling the pressure of various pressure media.

It is sectional drawing of the pressure control valve concerning the 1st Embodiment of this invention. It is a perspective view of the spring seat with which the pressure control valve of a 1st embodiment was equipped. It is a figure for demonstrating the clearance gap between a spring sheet | seat and the ball | bowl for sealing. It is a figure which shows the modification of a spring seat (the 1). It is a figure which shows the modification of a spring seat (the 2). It is a figure which shows the modification of a spring seat (the 3). It is the schematic which shows an example of the fuel-injection system of the internal combustion engine concerning the 2nd Embodiment of this invention. It is a figure which shows the relationship between the fuel pressure and discharge amount by a pressure control valve. It is sectional drawing which shows the structure of the pressure control valve which is not provided with the spring seat as a comparative example of this invention. It is sectional drawing which shows an example of the conventional pressure control valve. It is a figure which shows an example of the conventional pressure relief valve.

Explanation of symbols

10: pressure control valve, 16: fuel piping, 18: drain piping, 20: valve holder, 20A: pressure receiving port, 20B: open end, 21: first cylindrical portion, 22: second cylindrical portion, 23: exhaust Pressure port, 24: circumferential groove, 30: ball for sealing, 40: piston, 40a: hollow part, 41: communication hole, 50: spring, 60: spring seat, 60A: hole part, 61 / 61A: spring guide Part, 62: ball seat part, 63 / 63A: outer peripheral part, 65: seat surface, 67: edge, 100: fuel injection system, 101: common rail, 102: high pressure pump, 102A: suction port, 102B: cylinder chamber, 102C : Cam chamber, 103: low pressure pump, 104: filter, 105: fuel tank, 106: fuel supply path, 107: flow control valve, 108: fuel supply path, 109 Filter: 110: Pressure control valve, 110A: Pressure receiving port, 110B: Exhaust pressure port, 110C: Extraction port, 111: Check valve, 112: Fuel piping, 113: Drain piping, 114: Orifice, 115: Lubricating oil line, 120: Fuel supply pump

Claims (6)

A spring housing portion and a cylinder portion, wherein a first cylindrical space portion is formed in the spring housing portion, a second cylindrical space portion is formed in the cylinder portion, and the first cylindrical space portion and the first cylindrical space portion are formed. A valve holder having two cylindrical spaces communicating in the axial direction and having both ends opened;
A sealing ball which is press-fitted from the opening end on the first cylindrical space side and seals the opening end;
A piston slidably disposed in the second cylindrical space;
In a pressure control valve comprising a spring housed in the first cylindrical space and sandwiched between the sealing ball and the piston,
The open end of the second cylindrical space is desired on the high pressure side,
The cylinder part of the valve holder is provided with a discharge port that communicates with the high-pressure part side as the piston moves.
The piston is capable of reciprocating in the axial direction by the biasing force of the spring and the pressure on the high pressure portion side, and the exhaust pressure port is closed when the pressure of the high pressure portion is a predetermined value or less, and the high pressure portion When the pressure exceeds a predetermined value, it moves against the urging force of the spring, the exhaust pressure port communicates, and the pressure in the high pressure part can be released,
Between the spring and the sealing ball, an outer peripheral part corresponding to an inner peripheral surface of the first cylindrical space part, a spring guide part defining a radial position of the spring, and the sealing ball And a ball seat portion on which a spring is seated.   The pressure control valve according to claim 1, wherein the spring guide portion includes a protrusion having an outer diameter that matches the inner diameter of the spring.   3. The pressure control valve according to claim 1, wherein the outer peripheral portion includes a cylindrical portion that protrudes in the axial direction from a circumferential edge portion of the spring seat.   The pressure control valve according to claim 3, wherein the cylindrical portion as the outer peripheral portion and the protrusion as the spring guide portion protrude in opposite directions along the axial direction.   5. The pressure control valve according to claim 3, wherein the cylindrical portion projects from the sealing ball side and has a gap between the cylindrical portion and the sealing ball. A spring housing portion and a cylinder portion, wherein a first cylindrical space portion is formed in the spring housing portion, a second cylindrical space portion is formed in the cylinder portion, and the first cylindrical space portion and the first cylindrical space portion are formed. Two cylindrical space portions communicating in the axial direction and having both ends opened, a sealing ball that is press-fitted from the opening end on the first cylindrical space portion side and seals the open end, A pressure control valve comprising: a piston slidably disposed in a second cylindrical space; and a spring accommodated in the first cylindrical space and sandwiched between the sealing ball and the piston. In the fuel supply pump provided,
The open end of the second cylindrical space in the pressure control valve is desired on the high pressure side,
The cylinder part of the valve holder is provided with a discharge port that communicates with the high-pressure part side as the piston moves.
The piston is capable of reciprocating in the axial direction by the biasing force of the spring and the pressure on the high pressure portion side, and the exhaust pressure port is closed when the pressure of the high pressure portion is a predetermined value or less, and the high pressure portion When the pressure exceeds a predetermined value, it moves against the urging force of the spring, the exhaust pressure port communicates, and the pressure in the high pressure part can be released,
Between the spring and the sealing ball, an outer peripheral part corresponding to an inner peripheral surface of the first cylindrical space part, a spring guide part defining a radial position of the spring, and the sealing ball A fuel supply pump, comprising: a spring seat having a ball seat portion on which is seated.

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