JP2015075049A - High-pressure pump - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a high-pressure pump which can maintain a stable valve-opening operation and a valve-closing operation of a discharge valve.SOLUTION: In a high-pressure pump, a cylindrical union 61 is fixed to an inner wall of a fuel discharge part attachment hole which is formed at an upper housing. A seat member 70 is arranged at the diameter inner side of the union 61, and a discharge value 80 is seated on/off to/from a valve seat 76 which is arranged at the fuel outlet side of a first flow passage 71 possessed by the seat member 70. A stopper member 90 for limiting a movement amount of the discharge valve 80 in a valve-opening direction forms a second flow passage 92 which makes fuel having flowed out of the first flow passage 71 flow to the fuel outlet side, and is pressed into an inner wall of the union 61 in a radial inside direction to be fixed. By this constitution, since the stopper member 90 can be made of a hard material which is applied with heat treatment or the like, even if the abutment and separation of an abutment face 93 of the stopper member 90 and the discharge value 80 are repeated, the wear of the abutment face 93 of the stopper member 90 is suppressed.

Description

  The present invention relates to a high pressure pump.

Conventionally, a high-pressure pump that pressurizes fuel in a pressurizing chamber in a pump body by a reciprocating movement of a plunger is known. The high pressure pump discharges pressurized fuel from a fuel discharge portion to a fuel rail of the internal combustion engine by opening a discharge valve provided in a fuel passage communicating with the pressurizing chamber.
In the high-pressure pump described in Patent Literature 1, a seat member that constitutes a fuel discharge portion is press-fitted and fixed to an inner wall of a fuel passage provided in the pump body. The seat member is formed in a cylindrical shape, and has a large-diameter cylindrical portion that is press-fitted and fixed to the inner wall of the fuel passage, and a small-diameter cylindrical portion that is formed smaller in outer diameter than the large-diameter cylindrical portion and extends to the fuel outlet side. Have one. The discharge valve is seated and separated from the valve seat formed on the end face of the small diameter cylindrical portion on the fuel outlet side. A bottomed cylindrical stopper member provided with a predetermined clearance outside the small-diameter cylindrical portion is welded and fixed to the small-diameter cylindrical portion, and restricts the amount of movement of the discharge valve in the valve opening direction.

JP 2011-80391 A

However, since the high-pressure pump described in Patent Document 1 has a predetermined clearance between the small-diameter cylindrical portion of the seat member and the stopper member, the stopper member is caused by an impact when the discharge valve contacts the stopper member. May vibrate. As a result, there is a concern that the spring provided on the inner side of the stopper member and the discharge valve will rattle and the valve opening and closing operations of the discharge valve will deteriorate. Further, when the stopper member vibrates, there is a possibility that a crack is generated at the welded portion between the sheet member and the stopper member.
If the sheet member and the stopper member are fixed not by welding but by press-fitting, either the sheet member or the stopper member is formed of a low hardness material that is not subjected to heat treatment or the like. In that case, if the surface of the seat member or the stopper member is worn due to repeated opening and closing operations of the discharge valve, the opening and closing operations of the seat member deteriorate, and the once discharged fuel is returned to the pressurizing chamber. May be sucked back. When this suck back phenomenon occurs, the fuel discharge amount of the high-pressure pump decreases.

Further, in the high-pressure pump described in Patent Document 1, since the seat member constituting the fuel discharge portion is press-fitted and fixed in the fuel passage of the pump body, the fuel discharge portion is not configured as a subassembly. For this reason, maintenance performance such as replacement of parts of the fuel discharge portion is low.
The present invention has been made in view of the above problems, and an object of the present invention is to provide a high-pressure pump capable of maintaining a stable valve opening operation and valve closing operation of a discharge valve.

  The present invention limits the amount of movement of the discharge valve in the valve opening direction in a high-pressure pump including a discharge valve that can be seated on and separated from a valve seat of a seat member provided inside the diameter of a union fixed to the pump body. The stopper member is press-fitted and fixed to the inner wall of the union in the radial direction.

  This makes it possible to form the stopper member from a hard material that has been subjected to heat treatment or the like, so that even when the contact surface of the stopper member and the discharge valve repeat contact and separation, the contact surface of the stopper member Wear is suppressed. In addition, since the vibration of the stopper member when the contact surface of the stopper member and the discharge valve come into contact with each other is suppressed, rattling of the discharge valve is prevented. Therefore, the stable opening and closing operations of the discharge valve are maintained without rattling when the discharge valve is opened and closed. As a result, the fuel pump is prevented from sucking back, so that the fuel discharge amount can be prevented from decreasing.

It is sectional drawing of the high pressure pump by 1st Embodiment of this invention. It is sectional drawing of the fuel discharge part with which the high pressure pump of 1st Embodiment is provided. It is sectional drawing which shows the valve opening state of the discharge valve of 1st Embodiment. It is sectional drawing of the fuel discharge part with which the high pressure pump of 2nd Embodiment is provided. It is sectional drawing which shows the valve opening state of the discharge valve of 2nd Embodiment. It is sectional drawing of the fuel discharge part with which the high pressure pump of 3rd Embodiment is provided. It is sectional drawing which shows the valve opening state of the discharge valve of 3rd Embodiment. It is sectional drawing of the fuel discharge part with which the high pressure pump of 4th Embodiment is provided. It is sectional drawing which shows the valve opening state of the discharge valve of 4th Embodiment. It is sectional drawing of the fuel discharge part with which the high pressure pump of 5th Embodiment is provided. It is sectional drawing which shows the valve opening state of the discharge valve of 5th Embodiment. It is sectional drawing of the fuel discharge part with which the high pressure pump of 6th Embodiment is provided. It is sectional drawing which shows the valve opening state of the discharge valve of 6th Embodiment.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
(First embodiment)
A first embodiment of the present invention is shown in FIGS. The high-pressure pump 1 of the first embodiment pressurizes fuel pumped up from a fuel tank (not shown) by a low-pressure pump and discharges it to a delivery pipe (not shown). The fuel accumulated in the delivery pipe is injected into the cylinder of the internal combustion engine from an injector connected thereto.

As shown in FIG. 1, the high-pressure pump 1 includes a cylinder 10, a plunger 11, a lower housing 12, an upper housing 13, a cover 30, a fuel supply unit 40, an electromagnetic drive unit 50, a fuel discharge unit 60, and the like.
The cylinder 10 and the upper housing 13 of this embodiment correspond to an example of a “pump body” described in the claims.

The cylinder 10 is formed in a cylindrical shape, and a plunger 11 is accommodated therein so as to be able to reciprocate. The lower housing 12 and the upper housing 13 are fixed to the outer wall of the cylinder 10 in the radially outward direction. The lower housing 12 can be attached to a mounting hole provided in an internal combustion engine (not shown).
The cover 30 is formed in a bottomed cylindrical shape, and an opening end thereof is liquid-tightly fixed to the lower housing 12. A fuel chamber 31 filled with fuel is formed inside the cover 30. The cover 30 is provided with a fuel inlet (not shown). The fuel drawn from the fuel tank is supplied to the fuel inlet. Therefore, fuel is supplied from the fuel inlet to the fuel chamber 31.

  A pulsation damper 32 is provided inside the cover 30. The outer edge of the pulsation damper 32 is sandwiched between the upper fixing member 33 and the lower fixing member 34, and is installed between the upper housing 13 and the cover 30. In the pulsation damper 32, the outer edges of the two diaphragms 35 and 36 are joined, and a gas having a predetermined pressure is sealed in an inner sealed space. The pulsation damper 32 reduces the fuel pressure pulsation in the fuel chamber 31 by elastically deforming the two diaphragms 35 and 36 in the thickness direction with the center portion at the center according to the change in the fuel pressure in the fuel chamber 31. .

  A first spring 16 is provided between an oil seal holder 14 fixed to the lower housing 12 and a spring seat 15 fixed to the lower end portion of the plunger 11. The first spring 16 biases the plunger 11 to the camshaft of the internal combustion engine. Therefore, the plunger 11 reciprocates in the axial direction along the profile of the camshaft.

A pressurizing chamber 17 is formed between the upper end portion of the plunger 11 and the inner wall of the cylinder 10. The cylinder 10 has a suction hole 18 that opens to one side in the radial direction from the pressurizing chamber 17 and a discharge hole 19 that opens to the other side.
The upper housing 13 is formed in a substantially rectangular parallelepiped, and a hole 131 provided in the center is oil-tightly fastened to the cylinder 10 and fixed to the upper side of the lower housing 12. The upper housing 13 has a fuel supply portion attachment hole 132 that communicates with the suction hole 18 of the cylinder 10 and a fuel discharge portion attachment hole 133 that communicates with the discharge hole 19 of the cylinder 10.

The fuel supply unit 40 includes an intake valve body 41, an intake valve seat member 42, an intake valve 43, a stopper member 44, and the like.
The intake valve body 41 is formed in a cylindrical shape and is fixed to the fuel supply portion mounting hole 132 of the upper housing 13.
A cylindrical intake valve seat member 42 is provided inside the intake valve body 41. The suction chamber 45 formed inside the suction valve seat member 42 communicates with the fuel chamber 31 outside the upper housing through a hole 46 provided in the upper housing 13. The suction valve seat member 42 has a valve seat 47 at the opening of the suction chamber 45 on the pressurizing chamber side.
The suction valve 43 is provided on the pressure chamber side of the valve seat 47, and can be seated or separated from the valve seat 47. The suction valve 43 contacts the stopper member 44 when the valve is opened.
A second spring 48 is provided between the stopper member 44 and the suction valve 43. The second spring 48 biases the suction valve 43 toward the valve seat.

The electromagnetic drive unit 50 includes a flange 51, a fixed core 52, a movable core 53, a rod 54, a coil 55, a third spring 56, and the like.
The flange 51 is fixed to the outer wall of the intake valve body 41. A movable core 53 is provided inside the suction valve body 41 so as to be reciprocally movable. A rod 54 is fixed at the center of the movable core 53. A guide member 57 fixed to the inside of the suction valve body 41 supports the rod 54 so as to be capable of reciprocating in the axial direction. The third spring 56 biases the movable core 53 and the rod 54 toward the pressurizing chamber. The rod 54 can press the suction valve 43 toward the pressurizing chamber.

A fixed core 52 is provided on the side of the movable core 53 opposite to the pressure chamber, and a coil 55 is provided on the radially outer side of the fixed core 52. When the coil 55 is energized through the terminal 581 of the connector 58, magnetic flux flows through a magnetic circuit constituted by the movable core 53, the fixed core 52, the flange 51, the yoke 59, etc., and the movable core 53 and the rod 54 are connected to the third spring. It is magnetically attracted to the fixed core side against the urging force of 56.
On the other hand, when the energization to the coil 55 is stopped, the magnetic flux flowing through the magnetic circuit described above disappears, and the movable core 53 and the rod 54 are urged toward the pressurizing chamber by the third spring 56.

  2 and 3, the fuel discharge section 60 includes a union 61, a seat member 70, a discharge valve 80, a fourth spring 84, a stopper member 90, a relief valve 20, a spring holder 22, a fifth spring 25, and the like. Have Among these, the sheet member 70, the discharge valve 80, the stopper member 90, and the relief valve 20 are made of a hard material such as heat-treated martensitic stainless steel. In addition, these materials should just have high hardness, and are not restricted to the material.

The union 61 is formed in a cylindrical shape, and is fixed to the inner wall of the fuel discharge portion mounting hole 133 of the upper housing 13 with a screw 62. The end of the union 61 on the side opposite to the pressurizing chamber is a fuel outlet 63 of the high-pressure pump 1. The passage formed inside the fuel discharge portion mounting hole 133 of the upper housing 13 corresponds to an example of a “fuel passage” recited in the claims.
The union 61 is formed so that the inner diameter on the fuel outlet side is smaller than the inner diameter on the pressurizing chamber side at a position where an end surface on the fuel outlet side of the stopper member 90 described later is located, and has a step 64 at a position where the inner diameter changes. . The union 61 regulates the movement of the stopper member 90 to the fuel outlet side by the step 64.

The sheet member 70 is provided on the inner side of the union 61. The sheet member 70 includes a sheet member main body 73 in which a plurality of flow paths 71 and 72 are formed, a cylindrical portion 74 that extends from the sheet member main body 73 toward the axial pressure chamber, and a cylindrical portion thereof. It has the latching end 75 extended cyclically | annularly from the edge part of the 74 pressurizing chamber side to a radial direction.
The sheet member main body 73 includes a plurality of first flow paths 71 communicating in the axial direction, and a relief flow path 72 formed without communicating with the first flow paths 71. A discharge valve 80 can be seated and separated from a valve seat 76 provided at an opening on the fuel outlet side of the first flow path 71.
The sheet member 70 is inserted into the union 61 from the pressurizing chamber side, and the outer wall in the radially outward direction of the cylindrical portion 74 is press-fitted and fixed to the inner wall of the union 61. The seat member 70 is restricted from moving to the fuel outlet side by the locking end 75 being locked to the end surface of the union 61 on the pressurizing chamber side.

The discharge valve 80 includes a disc portion 81 that can be seated on the valve seat 76 of the seat member 70, and a cylinder portion 82 that extends from the disc portion 81 to the fuel outlet side.
The disc part 81 of the discharge valve 80 closes the first flow path 71 by being seated on the valve seat 76 of the seat member 70, and opens the first flow path 71 by being separated from the valve seat 76.
The cylindrical portion 82 of the discharge valve 80 is in sliding contact with a guide surface 91 formed on the inner wall of the stopper member 90 in the radially inner direction. By this guide surface 91, the discharge valve 80 is guided in the axial direction, and movement in the radial direction is restricted.

The stopper member 90 is formed in a bottomed cylindrical shape, is inserted into the union 61 from the pressurizing chamber side, and the outer wall in the radially outward direction is press-fitted and fixed to the inner wall in the radially inward direction of the union 61. The stopper member 90 has its end face on the fuel outlet side abutting on the step 64 of the union 61 described above, so that movement toward the fuel outlet side is restricted.
A contact surface 93 with which the discharge valve 80 can contact is formed on the end surface of the stopper member 90 on the pressure chamber side. The amount of movement of the discharge valve 80 toward the fuel outlet is determined by the contact of the disc portion 81 of the discharge valve 80 with the contact surface 93.

  The stopper member 90 has a notch surface 94 on the outer wall in the radially outward direction. A second flow path 92 is formed between the notch surface 94 and the inner wall of the union 61. The second flow path 92 is located on the outer diameter side than the contact surface 93 of the stopper member 90. Since the discharge valve 80 and the contact surface 93 of the stopper member 90 are in contact with each other when the discharge valve 80 is opened, the fuel that has flowed out of the first flow path 71 of the seat member 70 moves outside the diameter of the discharge valve 80. And flows through the second flow path 92 formed outside the diameter of the stopper member 90.

A fourth spring 84 is provided inside the diameter of the stopper member 90. One end of the fourth spring 84 contacts the discharge valve 80 and the other end contacts the inner wall of the bottom portion 95 of the stopper member 90. The fourth spring 84 biases the discharge valve 80 against the valve seat 76 of the seat member 70.
The fourth spring 84 of this embodiment corresponds to an example of a “spring” recited in the claims.
On the end surface of the discharge valve 80 on the fourth spring side, a locking portion 85 that is recessed toward the pressurizing chamber is provided. The inner wall in the radial direction of the locking portion 85 locks a portion of the fourth spring 84 other than the effective spring of about one turn or one and a half turns. Thereby, the movement of the fourth spring 84 in the radial direction is restricted. Therefore, friction between the inner wall in the radially inner direction of the cylinder portion 82 on the fuel outlet side with respect to the locking portion 85 of the discharge valve 80 and the fourth spring 84 is prevented.

On the other hand, the seat member 70 has a relief valve seat 77 at the opening of the relief flow path 72 on the pressurizing chamber side. The relief valve seat 77 is provided at the bottom of a recess 78 that is recessed from the end surface on the pressurizing chamber side of the seat member 70 toward the fuel outlet side.
The spherical relief valve 20 provided on the pressure chamber side of the relief valve seat 77 can be seated and separated from the relief valve seat 77. A relief valve holder 21 that supports the relief valve 20 is provided on the pressure chamber side of the relief valve 20.

The spring holder 22 is formed in a bottomed cylindrical shape, and is press-fitted and fixed to the inner wall in the radial inner direction of the cylindrical portion 74 of the sheet member 70. The spring holder 22 has a hole 23 that communicates in the radial direction. The fuel can flow through the hole 23.
A fifth spring 25 is provided inside the spring holder 22. One end of the fifth spring 25 is locked to the bottom 24 of the spring holder 22, and the other end is locked to the relief valve holder 21, and biases the relief valve holder 21 and the relief valve 20 toward the relief valve seat 77.

Next, the operation of the high-pressure pump 1 will be described.
(1) Suction stroke When the plunger 11 is lowered from the top dead center toward the bottom dead center by the rotation of the camshaft, the volume of the pressurizing chamber 17 increases and the fuel is depressurized. The discharge valve 80 is seated on the valve seat 76 and closes the first flow path 71.
On the other hand, the suction valve 43 moves to the pressurizing chamber side against the urging force of the second spring 48 due to the pressure difference between the pressurizing chamber 17 and the suction chamber 45 and is opened.
By opening the intake valve 43, the fuel in the fuel chamber 31 passes through the intake chamber 45 and flows into the pressurizing chamber 17.

(2) Metering stroke When the plunger 11 rises from the bottom dead center toward the top dead center due to the rotation of the camshaft, the volume of the pressurizing chamber 17 decreases. At this time, since energization to the coil 55 is stopped until a predetermined time, the rod 54 presses the suction valve 43 to the pressurizing chamber side by the urging force of the third spring 56. Therefore, the intake valve 43 maintains the valve open state.
By opening the intake valve 43, the pressurizing chamber 17 and the fuel chamber 31 are maintained in communication with each other. For this reason, the low-pressure fuel once sucked into the pressurizing chamber 17 is returned to the fuel chamber 31, and the fuel pressure in the fuel chamber 31 increases. On the other hand, the pressure in the pressurizing chamber 17 does not increase.

When the coil 11 is energized at a predetermined time while the plunger 11 rises from the bottom dead center toward the top dead center, the magnetic attraction between the fixed core 52 and the movable core 53 is caused by the magnetic field generated in the coil 55. Force is generated. When this magnetic attractive force becomes larger than the difference between the elastic force of the second spring 48 and the elastic force of the third spring 56, the movable core 53 moves to the fixed core side. Thereby, the pressing force of the rod 54 against the suction valve 43 is released.
Then, the suction valve 43 moves in the valve closing direction following the operation of the rod 54 by the elastic force of the second spring 48 and the dynamic pressure of the low pressure fuel discharged from the pressurizing chamber 17 to the suction chamber side. Sit on the valve seat 47. Thereby, the pressurizing chamber 17 and the suction chamber 45 are shut off.

(3) Discharge stroke After the intake valve 43 is closed, the fuel pressure in the pressurizing chamber 17 becomes higher as the plunger 11 rises. When the force that the fuel pressure in the pressurizing chamber 17 acts on the discharge valve 80 becomes larger than the sum of the force that the fuel pressure on the fuel outlet side acts on the discharge valve 80 and the urging force of the fourth spring 84, the discharge valve 80. Opens. Thereby, the high-pressure fuel pressurized in the pressurizing chamber 17 is discharged from the fuel outlet 63.
The state at this time is shown in FIG. As shown by an arrow A in FIG. 3, the fuel that has flowed into the inside of the spring holder 22 from the pressurizing chamber side through the hole 23 passes through the first flow path 71 of the seat member 70, and is radially outside the discharge valve 80. Through the second flow path 92 and discharged from the fuel outlet 63.

Note that energization of the coil 55 is stopped in the middle of the discharge stroke. Since the force that the fuel pressure in the pressurizing chamber 17 acts on the suction valve 43 is larger than the urging force of the third spring 56, the suction valve 43 maintains the closed state.
The high-pressure pump 1 repeats an intake stroke, a metering stroke, and a discharge stroke, pressurizes and discharges an amount of fuel necessary for the internal combustion engine.

The relief valve 20 opens when the pressure of the fuel rail installed on the downstream side of the high-pressure pump 1 exceeds the allowable range and becomes abnormally high, but otherwise, the relief valve 20 is seated on the relief valve seat 77, and the relief valve 20 is opened. The flow path 72 is closed.
When the pressure of the fuel rail becomes abnormally high, the force that the fuel pressure on the fuel outlet side acts on the relief valve 20 is the force that the fuel pressure on the pressurizing chamber side acts on the relief valve 20 and the biasing force of the fifth spring 25. The relief valve 20 is opened when the sum becomes larger. As a result, the fuel on the fuel rail is returned to the pressurizing chamber 17. As a result, damage to the components of the fuel supply system provided on the downstream side of the fuel outlet 63 is prevented, and fuel injection from the injector becomes possible.

The high-pressure pump 1 of the first embodiment has the following operational effects.
(1) In the first embodiment, the stopper member 90 is press-fitted and fixed to the inner wall of the union 61 in the radial inner direction.
This makes it possible to form the stopper member 90 from a hard material that has been subjected to heat treatment or the like. Therefore, even when the contact surface 93 of the stopper member 90 and the discharge valve 80 repeatedly contact and separate, the stopper member 90 The wear of the 90 contact surfaces 93 is suppressed. Further, since the vibration of the stopper member 90 when the contact surface 93 of the stopper member 90 and the discharge valve 80 come into contact with each other is suppressed, rattling of the discharge valve 80 and the fourth spring 84 is prevented. Accordingly, the discharge valve 80 can be quickly and stably opened and closed without shaking when the discharge valve 80 is opened and closed. As a result, the fuel pump 1 is prevented from sucking back, so that the fuel discharge amount can be prevented from decreasing.

(2) In the first embodiment, the stopper member 90 has a guide surface 91 that guides the opening and closing operations of the discharge valve 80 on the inner wall on the inner diameter side.
Since the stopper member 90 can be formed of a hard material, even when the guide surface 91 of the stopper member 90 and the discharge valve 80 repeatedly slide, wear of the guide surface 91 of the stopper member 90 is suppressed. The Therefore, it is possible to maintain a stable valve opening operation and valve closing operation of the discharge valve 80 without rattling when the discharge valve 80 is opened and closed.

(3) In the first embodiment, the stopper member 90 has the second flow path 92 in the radially outward direction from the contact surface 93.
As a result, the fuel flowing out from the first flow path 71 flows through the second flow path 92 outside the stopper member 90 without flowing through the inside of the stopper member 90. Therefore, since the vibration of the fourth spring 84 is prevented, the stable valve opening operation and valve closing operation of the discharge valve 80 can be maintained.
Further, interference due to vibration between the inner wall of the stopper member 90 and the fourth spring 84 can be prevented.

(4) In the first embodiment, the stopper member 90 forms the second flow path 92 between the notch surface 94 and the inner wall of the union 61 by the notch surface 94 provided on the radially outer wall.
Thereby, the second flow path 92 can be formed with a simple configuration.

(Second Embodiment)
The fuel discharge part 60 of the high pressure pump 1 of 2nd Embodiment of this invention is shown in FIG.4 and FIG.5. Hereinafter, in a plurality of embodiments, the same numerals are given to the composition substantially the same as composition of a 1st embodiment mentioned above, and explanation is omitted.
In the second embodiment, the stopper member 910 includes a cup portion 911 having a low end and a flange portion 912 extending annularly in the radially outward direction from the end portion of the cup portion 911 on the pressure chamber side. An abutting surface 93 with which the discharge valve 80 can abut is formed on the end surface of the cup portion 911 on the pressurizing chamber side. The flange portion 912 is provided in the radially outward direction of the contact surface 93.
In the stopper member 910, the outer wall in the radially outward direction of the flange portion 912 is press-fitted and fixed to the inner wall in the radially inward direction of the union 610. Further, the stopper member 910 is restricted from moving toward the fuel outlet side because the end surface on the fuel outlet side of the flange portion 912 contacts the step 64 of the union 610.

The stopper member 910 has a second flow path 913 composed of a plurality of holes communicating with the flange portion 912 in the axial direction. A plurality of second flow paths 913 are located on the outer diameter side of the contact surface 93 of the stopper member 910, and a plurality of the second flow paths 913 are provided in the circumferential direction.
Since the discharge valve 80 and the contact surface 93 of the stopper member 910 are in contact with each other when the discharge valve 80 is opened, the fuel flowing out from the first flow path 71 of the seat member passes outside the diameter of the discharge valve 80. The second flow path 913 formed outside the diameter of the stopper member 910 flows. The second flow path 913 has a function of rectifying fuel flowing therethrough. Therefore, the fuel flowing from the second flow path 913 through the gap 914 between the inner wall of the union 610 and the cup portion 911 becomes a rectified flow, so that the pressure loss is reduced.
The stopper member 910 has a locking portion 915 that is recessed toward the fuel outlet side at the bottom of the cup portion 911. The radial movement of the fourth spring 84 is restricted by the radial inner wall of the locking portion 915. Therefore, the friction between the inner wall in the radially inner direction on the pressurizing chamber side than the locking portion 915 of the cup portion 911 and the fourth spring 84 is prevented.

The discharge valve 810 is formed in an annular shape and has a hole 811 in the center. The discharge valve 810 is a multi-unit that simultaneously closes or opens the plurality of first flow paths 71 by seating or separating from the plurality of valve seats 76 provided in the openings of the plurality of first flow paths 71 at the same time. It is a seat valve.
The seat member 70 has a shaft portion 79 extending from the seat member main body portion 73 toward the fuel outlet side. A relief flow path 72 is formed at the center of the shaft portion 79. The shaft 79 is inserted through a hole 811 provided in the discharge valve 810 and is in sliding contact with the inner wall of the hole 811. The discharge valve 810 is guided in the axial direction by the shaft portion 79, and movement in the radial direction is restricted.

  During the discharge stroke of the high-pressure pump 1, as shown by an arrow B in FIG. 5, the fuel that has flowed into the inside of the spring holder 22 from the pressurizing chamber side through the hole 23 passes through the first flow path 71 of the seat member 70. Then, the fuel is discharged from the fuel outlet 63 through the gap 914 between the inner wall of the union 610 and the cup portion 911 through the second flow path 913 through the outer diameter of the discharge valve 810. At this time, since the fuel flowing through the second flow path 913 is rectified, the fuel flowing from the second flow path 913 through the gap 914 between the inner wall of the union 610 and the cup portion 911 becomes a rectified flow, reducing pressure loss. Is done. As a result, a decrease in the fuel discharge amount of the high-pressure pump 1 is prevented.

The high-pressure pump 1 of the second embodiment has the following operational effects.
(1) In the second embodiment, the seat member 70 has a shaft portion 79 extending from the seat member main body portion 73 toward the axial fuel outlet side. This shaft portion 79 is inserted through a hole 811 provided in the discharge valve 810 and guides the opening and closing operations of the discharge valve 810.
Since the sheet member 70 is press-fitted and fixed to the inner wall of the union 610, it can be formed of a hard material. Therefore, even when the shaft portion 79 of the sheet member 70 and the inner wall of the hole 811 of the discharge valve 810 repeatedly slide, wear of the shaft portion 79 of the sheet member 70 is suppressed. Therefore, the stable valve opening operation and valve closing operation of the discharge valve 810 can be maintained.

(2) In the second embodiment, the stopper member 910 has an engaging portion 915 that abuts against one end of the fourth spring 84 in the axial direction and restricts movement in the radial direction.
Since the stopper member 910 can be formed of a hard material, even when the fourth spring 84 repeatedly expands and contracts, wear of the locking portion 915 of the stopper member 910 is suppressed. Therefore, rattling of the fourth spring 84 can be prevented, and stable valve opening and closing operations of the discharge valve 810 can be maintained.

(3) In the second embodiment, the stopper member 910 has a second flow path 913 that communicates in the axial direction of the flange portion 912.
The second flow path 913 can rectify the fuel flowing out from the first flow path 71 toward the fuel outlet 63. Therefore, since the pressure loss of the fuel passing through the inside of the union 610 is reduced, the fuel pump can prevent a decrease in the fuel discharge amount.

(Third embodiment)
The fuel discharge part 60 of the high pressure pump 1 of 3rd Embodiment of this invention is shown in FIG.6 and FIG.7.
In the third embodiment, the stopper member 920 is formed in an annular shape, and the outer wall in the radially outer direction is press-fitted and fixed to the inner wall in the radially inner direction of the union 620. Further, the stopper member 920 is restricted from moving toward the fuel outlet side because the end surface on the fuel outlet side contacts the step 64 of the union 620.
The stopper member 920 is formed so that the inner diameter on the fuel outlet side is smaller than the inner diameter on the pressurizing chamber side, and a step formed at a position where the inner diameter changes becomes a contact surface 921 on which the discharge valve 810 can contact. Further, the radially inner wall of the portion located closer to the pressurizing chamber than the contact surface 921 serves as a guide surface 91 that is in sliding contact with the radially outer wall of the discharge valve 810. By this guide surface 91, the discharge valve 810 is guided in the axial direction, and movement in the radial direction is restricted.
The outlet valve 810 is a multi-seat valve formed in an annular shape as in the second embodiment.

During the discharge stroke of the high-pressure pump 1, as shown by an arrow C in FIG. 7, the fuel that has flowed into the inside through the hole 23 of the spring holder 22 from the pressurizing chamber side passes through the first flow path 71 of the seat member 70. Then, the fuel is discharged from the fuel outlet 63 through the hole 811 of the discharge valve 810, the inside of the stopper member 920 and the inside of the fourth spring 84. At this time, since the fuel hardly crosses between the lines of the fourth spring 84, the vibration of the fourth spring 84 is suppressed. Therefore, the valve opening and closing operations of the discharge valve 810 are stable.
In the third embodiment, the stopper member 920 can have a simple configuration.

(Fourth embodiment)
The fuel discharge part 60 of the high pressure pump 1 of 4th Embodiment of this invention is shown in FIG.8 and FIG.9.
In the fourth embodiment, the stopper member 930 includes a cup portion 911 and a flange portion 912 as in the second embodiment. The discharge valve 830 includes a disc part 81 and a cylinder part 82 as in the first embodiment. A guide surface 91 is formed on the inner wall of the cup portion 911 of the stopper member 930. By this guide surface 91, the cylinder part 82 of the discharge valve 830 is guided in the axial direction, and the radial movement is restricted.

  During the discharge stroke of the high-pressure pump 1, as shown by an arrow D in FIG. 9, the fuel that has flowed into the inside of the spring holder 22 from the pressurizing chamber side through the hole 23 passes through the first flow path 71 of the seat member 70. Then, the fuel is discharged from the fuel outlet 63 through the outer side of the discharge valve 830, through the second flow path 913 of the stopper member 930, through the gap 914 between the inner wall of the union 630 and the cup portion 911. At this time, the fuel flowing through the second flow path 913 is rectified, and the pressure loss of the fuel flowing through the gap 914 between the inner wall of the union 610 and the cup portion 911 is reduced. As a result, a decrease in the fuel discharge amount of the high-pressure pump 1 is prevented.

Further, as shown by the arrow D1, a part of the fuel flowing out from the first flow path 71 of the seat member 70 passes through the central hole 831 of the discharge valve 830, and the inside of the stopper member 930 and the inside of the fourth spring 84, The fuel is discharged from the fuel outlet 63 through the hole 931 on the fuel outlet side of the stopper member 930.
At this time, since the fuel flowing inside the fourth spring 84 hardly crosses between the lines of the fourth spring 84, the vibration of the fourth spring 84 is suppressed. Therefore, the valve opening and closing operations of the discharge valve 810 are stable.
The fourth embodiment has the same operational effects as the first and second embodiments.

(Fifth embodiment)
The fuel discharge part 60 of the high pressure pump 1 of 5th Embodiment of this invention is shown in FIG.10 and FIG.11.
In the fifth embodiment, the stopper member 940 has a part of the inner wall in the radial inner direction cut out in the radial outer direction, and has a second flow path 941 there. Further, a part of the inner wall of the union 640 in the circumferential direction is cut out in the radially outward direction, and a third flow path 641 communicating with the second flow path 941 is formed there. A spring stopper 642 is fixed to the inner wall of the union 640. One end of the fourth spring 84 is locked to the discharge valve 810, and the other end is locked to the spring stopper 642.

During the discharge stroke of the high-pressure pump 1, as shown by an arrow E in FIG. 11, the fuel that has flowed into the inside through the hole 23 of the spring holder 22 from the pressurizing chamber side passes through the first flow path 71 of the seat member 70. As a result, the fuel is discharged from the fuel outlet 63 through the second flow path 941 of the stopper member 940 and the third flow path 641 of the union 640. Further, as indicated by an arrow E1, a part of the fuel flowing out from the first flow path 71 of the seat member 70 passes through the hole 811 of the discharge valve 810, and inside the stopper member 940 and the inside of the fourth spring 84, the spring The fuel is discharged from the fuel outlet 63 through the hole 643 of the stopper 642.
At this time, since the fuel flowing through the second flow path 941 and the fuel flowing through the inside of the fourth spring 84 hardly cross between the lines of the fourth spring 84, the vibration of the fourth spring 84 is suppressed. . Therefore, the valve opening and closing operations of the discharge valve 810 are stable.
In the fifth embodiment, the same effects as those in the first to third embodiments can be obtained, and the fuel flow path is widened, so that the pressure loss of the fuel can be reduced.

(Sixth embodiment)
The fuel discharge part 60 of the high pressure pump 1 of 6th Embodiment of this invention is shown in FIG.12 and FIG.13.
In the sixth embodiment, the stopper member 950 has an abutment surface 951 on which the discharge valve 850 can abut and a guide surface 952 in sliding contact with an outer wall in the radially outward direction of the discharge valve 850 inside the cup portion 911.
The stopper member 950 is formed so that the inner diameter on the fuel outlet side is smaller than the inner diameter on the pressurizing chamber side. The contact surface 951 is a step formed at a position where the inner diameter changes. The guide surface 952 is an inner wall in the radially inward direction of the cup portion 911 located closer to the pressurizing chamber than the contact surface 951.
Further, the stopper member 950 has a second flow path 953 communicating in the radial direction on the pressurizing chamber side with respect to the contact surface 951.
The discharge valve 850 restricts the movement of the fourth spring 84 in the radial direction by a convex portion 851 that protrudes inside the fourth spring 84.

During the discharge stroke of the high-pressure pump 1, as shown by an arrow F in FIG. 13, the fuel that has flowed into the inside through the hole 23 of the spring holder 22 from the pressurizing chamber side passes through the first flow path 71 of the seat member 70. Then, it passes through the second flow path 953 of the stopper member 950, passes through the gap 914 between the inner wall of the union 650 and the cup portion 911, and is discharged from the fuel outlet 63.
The sixth embodiment has the same effects as the above-described embodiments.

(Other embodiments)
In the above-described embodiment, the fuel discharge unit includes a relief valve, a relief valve holder, and a fifth spring in addition to the seat member, the discharge valve, the stopper member, and the fourth spring. On the other hand, in other embodiments, the fuel discharge unit may include only the seat member, the discharge valve, the stopper member, and the fourth spring, and may not include the relief valve, the relief valve holder, and the fifth spring. In this case, the sheet member can have no relief flow path.
The present invention is not limited to the above-described plurality of embodiments. In addition to combining the above-described plurality of embodiments, the present invention can be implemented in various forms without departing from the spirit of the invention.

1 ... High pressure pump 13 ... Upper housing (pump body)
61, 610, 620, 630, 640, 650 ... Union 71 ... First flow path 70 ... Sheet member 76 ... Valve seat 80, 810, 830, 850 ... Discharge valve 84 ...・ Fourth spring (spring)
92,913,941,953 ... 2nd flow path 90,910,920,930,940,950 ... stopper member

Claims (8)

A pump body (10, 13) having a fuel passage (133) communicating with a pressurizing chamber (17) in which fuel is pressurized;
A cylindrical union (61, 610, 620, 630, 640, 650) fixed to the inner wall of the fuel passage and having a fuel outlet (63) on the side opposite to the axial pressure chamber;
A sheet member (70) provided on the inner diameter side of the union and having a first flow path (71) communicating in the axial direction;
A discharge valve (80, 810, 830, 850) that can be seated and separated from a valve seat (76) provided at an opening on the fuel outlet side of the first flow path;
A spring (84) for urging the discharge valve against the valve seat;
A second flow path (92, 913, 941, 953) that is press-fitted and fixed to the inner wall of the union in the radial direction and flows the fuel flowing out from the first flow path to the fuel outlet side is formed, and the discharge valve is opened. A high-pressure pump (1) comprising a stopper member (90, 910, 920, 930, 940, 950) for limiting the amount of movement in the valve direction.   The stopper member (90, 920, 930, 940, 950) has a guide surface (91, 952) for guiding the opening and closing operations of the discharge valve on the inner wall on the inner diameter side. The high-pressure pump according to claim 1. The seat member is press-fitted and fixed to the radially inner wall of the union and extends from the end surface on the fuel outlet side where the valve seat is formed to the fuel outlet side in the axial direction and is provided in the discharge valve (810). Having a shaft portion (79) through which the hole (811) is inserted;
The high-pressure pump according to claim 1, wherein the shaft portion guides opening and closing operations of the discharge valve.   2. The stopper member (910, 930, 950) has a locking portion (915) that abuts against one end of the spring in the axial direction and restricts the radial movement of the spring. 4. The high pressure pump according to any one of items 1 to 3.   The stopper member (90, 910, 930, 940, 950) is arranged such that the second flow path (92, 913, 920) is more radially outward than the contact surface (93, 921, 951) that can contact the discharge valve. 941, 953). The high-pressure pump according to any one of claims 1 to 4,   The high-pressure pump according to claim 5, wherein the stopper member (90) has a notch surface (94) that forms the second flow path (92) on an outer wall in a radially outward direction. The stopper member (910, 930) has a flange portion (912) extending annularly from the contact surface in the radially outward direction,
The high-pressure pump according to claim 5, wherein the second flow path (913) communicates with an axial direction of the flange portion.   The high-pressure pump according to claim 7, wherein a plurality of the second flow paths are provided in a circumferential direction of the flange portion.

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