JP2020034003A - High-pressure pump - Google Patents

Abstract

To provide a high-pressure pump which can suppress a secular change of the valve-opening pressure of a relief valve member.SOLUTION: A valve seat part 60 has a relief valve passage 68 formed at a valve seat part main body 61, and returning fuel in a discharge passage 102 to a pressurization chamber side, and a relief valve seat 612 which is annularly formed around an opening of the relief valve passage 68 of the valve seat part main body 61 at the pressurization chamber side. The relief valve member 80 has a relief valve main body 81, and a relief valve seat part 82 which is formed at one end of the relief valve main body 81 integrally with the relief valve main body 81 so as to be capable of abutting on the relief valve seat 612, and formed inside a valve seat part 60 so as to be reciprocal to an axial direction. The relief valve seat part 82 has a first tapered face 821, and a second tapered face 822 connected to the first tapered face 821, and located at a side opposite to the pressurization chamber with respect to the first tapered face 821. An inclination angle of the first tapered face 821 with respect to the relief valve seat 612 is smaller than an inclination angle of the second tapered face 822 with respect to the relief valve seat 612.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a high-pressure pump that pressurizes and discharges fuel.

  2. Description of the Related Art Conventionally, there has been known a high-pressure pump in which a discharge valve and a relief valve are integrally provided in a discharge passage through which fuel pressurized in a pressurizing chamber flows. For example, in the high-pressure pump disclosed in Patent Literature 1, a spherical valve is used as a valve body of a relief valve.

Japanese Patent No. 5501272

  The high-pressure pump disclosed in Patent Literature 1 includes a holder for holding a valve element of a relief valve, and an urging member for urging the valve element toward a valve seat via the holder. Here, the movement of the valve body and the holder is not guided by another member, and the valve body and the holder can relatively freely move in the space on the pressurizing chamber side with respect to the valve seat. Fuel discharged from the pressurized chamber of the high-pressure pump flows around the valve body and the holder and is discharged to the outside of the high-pressure pump. Therefore, the valve element and the holder may move or vibrate due to the flow of the fuel. If the valve body moves or vibrates while the valve body is in contact with the valve seat, the valve seat or the valve body may be worn. When the valve seat or the valve element wears, the valve opening pressure of the relief valve may change with time.

  Further, in the high-pressure pump disclosed in Patent Document 1, since the valve element and the holder are formed separately, the valve element and the holder may move relative to each other, and the position of the valve element may become unstable. As a result, wear of the valve seat or the valve body may be promoted.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to provide a high-pressure pump capable of suppressing a change over time of a valve opening pressure of a relief valve member.

A high-pressure pump according to the present invention includes a pump body, a valve seat, a relief valve member, and a relief valve biasing member.
The pump body has a pressurizing chamber for pressurizing the fuel, and a discharge passage through which the fuel pressurized and discharged in the pressurizing chamber flows.
The valve seat has a valve seat body, a relief valve passage, and a relief valve seat.

  The valve seat body is provided in the discharge passage. The relief valve passage is formed in the valve seat body and returns the fuel in the discharge passage to the pressurizing chamber side. The relief valve seat is formed in an annular shape around the opening on the pressurizing chamber side of the relief valve passage of the valve seat body.

The relief valve member has a relief valve body and a relief valve seat.
The relief valve seat portion is formed integrally with the relief valve main body at one end of the relief valve main body so as to be able to contact the relief valve seat. The relief valve member is provided inside the valve seat so as to be able to reciprocate in the axial direction.
The relief valve urging member urges the relief valve member toward the relief valve seat.

  In the present invention, the relief valve seat has a first tapered surface and a second tapered surface. The second tapered surface is connected to the first tapered surface and located on the opposite side of the first tapered surface from the pressure chamber.

  In the present invention, the inclination angle of the first tapered surface with respect to the relief valve seat is smaller than the inclination angle of the second tapered surface with respect to the relief valve seat.

FIG. 1 is a schematic diagram showing a high-pressure pump according to a first embodiment of the present invention. FIG. 1 is a sectional view showing a high-pressure pump according to a first embodiment of the present invention. The enlarged view of the III section of FIG. FIG. 2 is a sectional view showing the vicinity of a relief valve seat of the high-pressure pump according to the first embodiment of the present invention. FIG. 2 is a cross-sectional view illustrating the discharge valve device of the high-pressure pump according to the first embodiment of the present invention, showing a state in which fuel flows to a fuel rail via a discharge valve seat. FIG. 2 is a cross-sectional view illustrating the discharge valve device of the high-pressure pump according to the first embodiment of the present invention, illustrating a state in which fuel flows to a pressurizing chamber via a relief valve seat. FIG. 7 is a sectional view showing the vicinity of a relief valve seat of a high-pressure pump according to a second embodiment of the present invention.

Hereinafter, high-pressure pumps according to a plurality of embodiments of the present invention will be described with reference to the drawings. In a plurality of embodiments, substantially the same components are denoted by the same reference numerals, and description thereof will be omitted. In addition, in a plurality of embodiments, substantially the same component has the same or similar operation and effect.
(1st Embodiment)
FIG. 2 shows a high-pressure pump according to a first embodiment of the present invention.

  The high-pressure pump 1 is provided in a vehicle (not shown). The high-pressure pump 1 is a pump that supplies fuel at a high pressure to an engine as an internal combustion engine, for example. The fuel supplied to the engine by the high-pressure pump 1 is gasoline, for example. That is, the fuel supply target of the high-pressure pump 1 is a gasoline engine.

As shown in FIG. 1, the fuel stored in the fuel tank 2 is supplied to the high-pressure pump 1 via a pipe 4 by a fuel pump 3. The high-pressure pump 1 pressurizes the fuel supplied from the fuel pump 3 and discharges the fuel to a fuel rail 7 via a pipe 6. Thereby, the fuel in the fuel rail 7 is accumulated and supplied to the engine from the fuel injection valve 8 connected to the fuel rail 7. As shown in FIG. 2, the high-pressure pump 1 includes a pump body 10, a cover 15, a pulsation damper 16, a plunger 20, a suction valve device 30, an electromagnetic drive unit 40, a discharge valve device 50, and the like.
The pump body 10 has an upper housing 11, a lower housing 12, a cylinder 13, a holder support 14, a union 51, and the like.

  The upper housing 11 is formed in a substantially rectangular parallelepiped block shape with a metal such as stainless steel, for example. The upper housing 11 has a suction hole 111, a discharge hole 112, a cylinder hole 113, a step 114, and the like. The suction hole 111 is formed at one end in the longitudinal direction of the upper housing 11 and is formed in a substantially cylindrical shape so as to extend in the longitudinal direction. Thus, the suction passage 101 is formed inside the suction hole 111. The discharge hole 112 is opened at the other end in the longitudinal direction of the upper housing 11, and is formed in a substantially cylindrical shape so as to extend in the longitudinal direction. Thus, the discharge passage 102 is formed inside the discharge hole 112. Here, the suction hole 111 and the discharge hole 112 are formed to be coaxial.

  The cylinder hole 113 is formed in a substantially cylindrical shape between the suction hole 111 and the discharge hole 112 so as to open at both ends in the short direction of the upper housing 11. Here, the space inside the cylinder hole 113 is connected to the suction passage 101 and the discharge passage 102. The step 114 is formed on the inner wall of the upper housing 11 that forms the discharge hole 112. The discharge hole 112 is formed such that the inner diameter on the suction hole 111 side with respect to the step 114 is smaller than the inner diameter on the side opposite to the suction hole 111 (see FIGS. 2 and 3).

  The lower housing 12 is formed in a plate shape from a metal such as stainless steel, for example. The lower housing 12 has a cylinder hole 121. The cylinder hole 121 is formed in a substantially circular shape so as to penetrate the lower housing 12 in the thickness direction. The lower housing 12 is provided so as to be fitted to the upper housing 11 such that the cylinder hole 113 and the cylinder hole 121 are coaxial. Here, the upper housing 11 and the lower housing 12 correspond to “housing” in the claims.

  The cylinder 13 is formed of a metal such as stainless steel into a bottomed cylindrical shape. The cylinder 13 has a suction hole 131 and a discharge hole 132. The suction hole 131 and the discharge hole 132 are formed near the bottom of the cylindrical portion of the cylinder 13 so as to face each other. That is, the suction hole 131 and the discharge hole 132 are formed so as to extend in the radial direction of the cylinder 13 so as to sandwich the axis of the cylinder 13. The cylinder 13 is inserted into the cylinder hole 113 of the upper housing 11 and the cylinder hole 121 of the lower housing 12 such that the suction hole 131 is connected to the suction passage 101 and the discharge hole 132 is connected to the discharge passage 102. ing. The outer wall at the bottom end of the cylinder 13 is fitted to the inner wall forming the cylinder hole 113 of the upper housing 11.

  The holder support portion 14 is formed in a substantially cylindrical shape by a metal such as stainless steel. The holder support portion 14 is provided so that one end thereof is connected to the opposite side of the upper housing 11 from the lower housing 12 so as to be coaxial with the cylinder 13. In the present embodiment, the holder support 14 is formed integrally with the lower housing 12.

  The union 51 is formed in a substantially cylindrical shape by a metal such as stainless steel, for example. The union 51 is provided such that one end is inserted into the discharge hole 112 of the upper housing 11. In the present embodiment, the union 51 has a thread on the outer wall at one end, and the upper housing 11 has a thread groove on the inner wall of the discharge hole 112. The union 51 is fixed to the upper housing 11 by being screwed into the discharge hole 112. The union 51 has a discharge passage 102 formed inside. The union 51 has a step 52. The step 52 is formed on the inner wall of the union 51. The union 51 is formed such that the inner diameter on the side of the step 114 with respect to the step 52 is larger than the inner diameter on the side opposite to the step 114 (see FIGS. 2 and 3). The other end of the union 51, that is, the end opposite to the upper housing 11 is connected to the end of the pipe 6 opposite to the fuel rail 7.

  The cover 15 is formed in a bottomed cylindrical shape, that is, a cup shape, for example, from a metal such as stainless steel. The cover 15 is provided so as to house the upper housing 11 inside and connect an end on the opening side to an outer edge of the lower housing 12. The cover 15 and the lower housing 12 are connected by welding all around. As a result, the space between the cover 15 and the lower housing 12 is kept liquid-tight. A fuel gallery 100 is formed between the inside of the cover 15 and the lower housing 12. The cover 15 has an inlet (not shown). A pipe 4 connected to the fuel pump 3 is connected to the inlet. Thereby, the fuel in the fuel tank 2 flows into the inside of the cover 15, that is, into the fuel gallery 100 via the inlet portion.

  The cover 15 has a first hole 151 and a second hole 152. The first hole 151 and the second hole 152 are formed to connect the inner wall and the outer wall of the cover 15, respectively. The first hole 151 and the second hole 152 are formed at positions corresponding to the suction hole 111 and the discharge hole 112 of the upper housing 11, respectively. Here, the union 51 is provided so as to be inserted into the second hole 152 of the cover 15 and the discharge hole 112 of the upper housing 11. In addition, the outer wall of the union 51 and the second hole 152 of the cover 15 are welded all around. As a result, the space between the union 51 and the cover 15 is kept liquid-tight.

  The pulsation damper 16 is provided between the bottom of the cover 15 and the upper housing 11. The pulsation damper 16 is formed, for example, by joining the peripheral edges of two diaphragms, and seals a gas of a predetermined pressure inside. An engaging member 161 is provided near the bottom of the cover 15. A damper supporting portion 162 is provided on the upper housing 11 side of the locking member 161. The damper support portion 162 supports the pulsation damper 16 by sandwiching the outer edge of the pulsation damper 16 between the damper support portion 161 and the engaging member 161. The pulsation damper 16 can reduce fuel pressure pulsation by elastically deforming according to a change in fuel pressure in the fuel gallery 100.

The plunger 20 is formed in a substantially columnar shape by a metal such as stainless steel. The plunger 20 has a large diameter portion 201 and a small diameter portion 202. The small diameter portion 202 has an outer diameter smaller than the outer diameter of the large diameter portion 201. The large diameter portion 201 and the small diameter portion 202 are integrally formed coaxially. The plunger 20 is provided such that the large-diameter portion 201 side is inserted inside the cylinder 13. The outer diameter of the large diameter portion 201 of the plunger 20 is substantially the same as the inner diameter of the cylinder 13 or slightly smaller than the inner diameter of the cylinder 13. Thus, the outer wall of the large diameter portion 201 slides on the inner wall of the cylinder 13, and the plunger 20 is supported by the cylinder 13 so as to be able to reciprocate in the axial direction.
A pressurizing chamber 103 is formed between the inner wall of the cylinder portion and the bottom portion of the cylinder 13 and the outer wall of the plunger 20 at the end on the large diameter portion 201 side. The pressure chamber 103 changes in volume when the plunger 20 reciprocates in the cylinder 13.

  In the present embodiment, the seal holder 21 is provided inside the holder support 14. The seal holder 21 is formed in a cylindrical shape from a metal such as stainless steel, for example. The seal holder 21 is provided such that the outer wall is fitted to the inner wall of the holder support 14. Further, the seal holder 21 is provided so as to form a substantially cylindrical clearance between the inner wall at the end opposite to the cylinder 13 and the outer wall of the small diameter portion 202 of the plunger 20. An annular seal 22 is provided between the inner wall of the seal holder 21 and the outer wall of the small diameter portion 202 of the plunger 20. The seal 22 is made of a Teflon (registered trademark) ring on the inner side and a rubber made on the outer side. Consisting of a ring. The seal 22 adjusts the thickness of the fuel oil film around the small diameter portion 202 of the plunger 20, and suppresses fuel leakage to the engine. An oil seal 23 is provided at an end of the seal holder 21 opposite to the cylinder 13. The oil seal 23 adjusts the thickness of the oil oil film around the small diameter portion 202 of the plunger 20 and suppresses oil leakage.

  In addition, between the step surface between the large diameter portion 201 and the small diameter portion 202 of the plunger 20 and the seal 22, a variable volume chamber 104 whose volume changes when the plunger 20 reciprocates is formed. In the present embodiment, the lower housing 12 has a hole 122 through which the fuel gallery 100 and the variable volume chamber 104 can communicate. Thus, the fuel in the fuel gallery 100 can flow between the variable volume chamber 104 via the hole 122.

  A substantially disk-shaped spring seat 24 is provided at an end of the small-diameter portion 202 of the plunger 20 opposite to the large-diameter portion 201. An urging member 25 is provided between the seal holder 21 and the spring seat 24. The urging member 25 is, for example, a coil spring, and is provided so that one end thereof contacts the spring seat 24 and the other end thereof contacts the seal holder 21. The urging member 25 urges the plunger 20 to the side opposite to the pressurizing chamber 103 via the spring seat 24.

The high-pressure pump 1 is provided on the engine such that an end of the small-diameter portion 202 of the plunger 20 opposite to the large-diameter portion 201 abuts on a cam 5 of a cam shaft that rotates in conjunction with a drive shaft of the engine. (See FIG. 1). Thus, when the engine is rotating, the rotation of the cam 5 causes the plunger 20 to reciprocate in the axial direction. At this time, the volumes of the pressurizing chamber 103 and the variable volume chamber 104 change periodically.
The suction valve device 30 is provided in the suction passage 101 of the upper housing 11. The suction valve device 30 has a suction valve seat 31, a suction valve member 32, a stopper 33, a suction valve urging member 34, and the like.

  The suction valve seat portion 31 is formed in a tubular shape by a metal such as stainless steel, for example. The suction valve seat portion 31 is provided such that an outer wall is fitted to an inner wall of the upper housing 11 forming the suction hole portion 111. The suction valve seat 31 has a suction valve seat 311. The suction valve seat 311 is formed in an annular shape around a central hole in a wall surface of the suction valve seat portion 31 on the pressurizing chamber 103 side.

  The suction valve member 32 is formed of, for example, a metal such as stainless steel. The suction valve member 32 has, for example, a substantially disk-shaped plate portion. The suction valve member 32 is provided such that the plate portion can contact the suction valve seat 311 and can reciprocate in the suction passage 101.

The stopper 33 is formed in a cylindrical shape with a bottom, for example, a metal such as stainless steel. The stopper 33 is provided so that the outer wall is fitted to the inner wall of the upper housing 11 forming the suction hole 111.
The suction valve urging member 34 is provided between the plate of the suction valve member 32 and the bottom of the stopper 33. The suction valve biasing member 34 biases the suction valve member 32 toward the suction valve seat 311.

  In the present embodiment, the fuel can flow between the suction valve seat 31 side and the pressurizing chamber 103 side with respect to the stopper 33 through the flow path formed at the outer edge of the stopper 33. The stopper 33 can restrict the movement of the suction valve member 32 toward the pressurizing chamber 103, that is, the movement in the valve opening direction, by abutting on the suction valve member 32. Further, since the stopper 33 has a bottom portion between the suction valve member 32 and the pressurizing chamber 103, it is possible to suppress the fuel in the pressurizing chamber 103 from colliding with the suction valve member 32.

  The electromagnetic drive unit 40 is provided near the suction valve device 30. The electromagnetic drive unit 40 includes a cylindrical member 41, a non-magnetic member 42, a needle 35, a needle guide 36, a needle urging member 37, a movable core 43, a fixed core 44, a coil 45, a connector 46, cover members 47 and 48, and the like. Have.

  The cylindrical member 41 is formed in a substantially cylindrical shape by, for example, a magnetic material. The cylindrical member 41 is provided so as to be inserted through the first hole 151 of the cover 15 and the suction hole 111 of the upper housing 11. The outer wall of one end of the cylindrical member 41 is fitted to the inner wall of the suction hole 111 of the upper housing 11. Here, the suction valve seat portion 31 and the stopper 33 are sandwiched between one end of the cylindrical member 41 and an inner wall forming the suction hole 111 of the upper housing 11. Further, inside the one end of the tubular member 41, the end of the suction valve seat 31 opposite to the suction valve seat 311 is located.

  The suction valve seat 31 has a hole 312 connecting the inner wall and the outer wall. A plurality of holes 312 are formed at equal intervals in the circumferential direction of the suction valve seat 31. In the present embodiment, two holes 312 are formed. That is, the two holes 312 are formed to face each other with the axis of the suction valve seat 31 interposed therebetween. The cylindrical member 41 has a groove 411 formed so as to be cut away from one end toward the other end. Two grooves 411 are formed, one at a position corresponding to the hole 312 of the suction valve seat 31. The upper housing 11 has a hole 115 connecting the inner wall and the outer wall forming the suction hole 111. A total of two holes 115 are formed at positions corresponding to the grooves 411 of the tubular member 41. The fuel in the fuel gallery 100 can flow into the inside of the suction valve seat 31 via the hole 115, the groove 411, and the hole 312. The fuel that has flowed into the inside of the suction valve seat portion 31 can flow between the suction valve seat 311 and the suction valve member 32 and to the pressurizing chamber 103 via the flow path of the stopper 33.

In addition, the entire space between the outer wall of the tubular member 41 and the first hole 151 of the cover 15 is welded. Thereby, the space between the tubular member 41 and the cover 15 is kept liquid-tight.
The non-magnetic member 42 is formed in a cylindrical shape from a non-magnetic material. The non-magnetic member 42 is provided on the side opposite to the upper housing 11 of the cylindrical member 41 so as to be coaxial with the cylindrical member 41.
The needle 35 is formed in a rod shape, for example, from metal. The needle 35 is provided to be able to reciprocate in the axial direction inside the tubular member 41. One end of the needle 35 can contact the suction valve member 32.

  The needle guide 36 is provided such that the outer wall is fitted to the inner wall of the tubular member 41. The needle guide 36 has a guide hole 361 at the center. The guide hole 361 is formed so as to connect the wall surface of the needle guide portion 36 on the side of the pressure chamber 103 to the wall surface on the opposite side of the pressure chamber 103. The needle 35 is inserted into the guide hole 361. The inner diameter of the guide hole 361 is formed to be approximately the same as or slightly larger than the outer diameter of the needle 35. The inner wall of the guide hole 361 and the outer wall of the needle 35 are slidable. Thus, the needle guide 36 can guide the movement of the needle 35 in the axial direction.

The needle urging member 37 is, for example, a coil spring, and is provided on the pressurizing chamber 103 side of the needle guide 36. The needle urging member 37 is provided such that one end thereof abuts on a protruding portion projecting annularly outward from the needle 35 and the other end abuts the needle guide portion 36. The needle urging member 37 urges the needle 35 toward the pressurizing chamber 103. Therefore, the needle urging member 37 can urge the suction valve member 32 toward the stopper 33 via the needle 35.
The movable core 43 is formed in a substantially cylindrical shape from a magnetic material, and is press-fitted into the other end of the needle 35. Thus, the movable core 43 can reciprocate in the axial direction together with the needle 35.
The fixed core 44 is formed of a magnetic material into a solid cylindrical shape, and is provided on the movable core 43 on the side opposite to the pressure chamber 103. The end of the fixed core 44 on the side of the pressure chamber 103 is connected to the non-magnetic member 42.

  The coil 45 is formed in a substantially cylindrical shape, and is provided radially outside the fixed core 44 and the nonmagnetic member 42. The periphery of the coil 45 is molded with a resin material to form a connector 46. Terminals 461 are insert-molded in the connector 46. The terminal 461 and the coil 45 are electrically connected.

  The cover members 47 and 48 are formed of a magnetic material. The cover member 47 is formed in a cylindrical shape with a bottom, accommodates the fixed core 44 and the coil 45 inside, and is provided so that the bottom portion contacts the fixed core 44. The cover member 48 is formed in a plate shape and has a hole at the center. The cover member 48 is provided so as to close the open end of the cover member 47 with the other end of the cylindrical member 41 inserted through the hole. Here, the cover member 48 is in contact with the cover member 47 and the tubular member 41.

  The coil 45 generates a magnetic field when electric power is supplied from the outside via the terminal 461. When a magnetic field is generated in the coil 45, a magnetic circuit is formed in the fixed core 44, the cover member 47, the cover member 48, the tubular member 41, and the movable core 43, and the movable core 43 is attracted to the fixed core 44 together with the needle 35. At this time, the magnetic circuit is formed so as to avoid the nonmagnetic member 42.

When power is not supplied to the coil 45, the suction valve member 32 is urged toward the pressurizing chamber 103 by the urging force of the needle urging member 37 via the needle 35, and the surface of the stopper 33 is Is brought into contact with. At this time, since the suction valve member 32 is separated from the suction valve seat 311, the flow of fuel in the suction passage 101 and the suction hole 131 is allowed. On the other hand, when power is supplied to the coil 45 and the movable core 43 and the needle 35 are attracted to the fixed core 44 side, the suction valve member 32 is urged by the urging force of the suction valve urging member 34 and the like. It moves to the opposite side to the pressurizing chamber 103 and contacts the suction valve seat 311. Thereby, the flow of the fuel in the suction passage 101 and the suction hole 131 is shut off.
As described above, the suction valve device 30 can allow or block the flow of the fuel in the suction passage 101 and the suction hole 131 by the operation of the electromagnetic drive unit 40. In the present embodiment, the suction valve device 30 constitutes a so-called normally open type valve device together with the electromagnetic drive unit 40.

Next, the discharge valve device 50 of the high-pressure pump 1 according to the present embodiment will be described in detail.
As shown in FIG. 3, the discharge valve device 50 includes a valve seat portion 60, a discharge valve member 70, a discharge valve urging member 71, a relief valve member 80, a relief valve urging member 89, a support portion 90, and the like. .
The valve seat portion 60 is formed of a metal such as stainless steel, for example, and is provided inside the union 51.
The valve seat portion 60 has a valve seat portion main body 61, a discharge valve passage 67, a relief valve passage 68, a discharge valve seat 611, a relief valve seat 612, a valve seat tube portion 62, and a valve seat projecting portion 63.

  The valve seat body 61 is formed in the discharge passage 102 so as to divide the discharge passage 102 into a first space 105 which is a space on the pressurizing chamber 103 side and a second space 106 which is a space on the opposite side to the pressurizing chamber 103. Is provided. The valve seat body 61 is provided such that an outer wall of the pressurizing chamber 103 is in contact with an inner wall of the union 51. A cylindrical space 107, which is a substantially cylindrical space, is formed between the outer wall of the valve seat body 61 opposite to the pressurizing chamber 103 and the inner wall of the union 51.

  The valve seat body 61 has a concave portion 65 formed so as to be concave from the center of the end face on the first space 105 side toward the second space 106 side. The concave portion 65 has a bottom portion 651, a cylindrical portion 652, and a tapered portion 653 (see FIG. 4). The bottom portion 651 is formed in a tapered shape such that the inner wall approaches the axis of the valve seat portion main body 61 from the first space 105 side toward the second space 106 side. The cylindrical portion 652 is formed to extend from the outer edge of the bottom portion 651 toward the pressurizing chamber 103. The cylindrical portion 652 has a substantially cylindrical inner wall. The tapered portion 653 is formed so as to extend from the end opposite to the bottom 651 of the cylindrical portion 652 to the pressurizing chamber 103 side and open to the end face of the valve seat body 61 on the pressurizing chamber 103 side. The tapered portion 653 is formed in a tapered shape such that the inner wall approaches the axis of the valve seat portion main body 61 from the first space 105 side toward the second space 106 side.

  The valve seat body 61 has a protrusion 64 formed to protrude from the center of the end face on the second space 106 side to the second space 106 side. The protruding portion 64 is formed in a tapered shape such that the outer wall approaches the axis from the first space 105 side to the second space 106 side. Further, the valve seat body 61 has a concave portion 66 formed so as to be recessed from the end face of the protruding portion 64 opposite to the pressurizing chamber 103 toward the pressurizing chamber 103.

  The discharge valve passage 67 is formed in the valve seat body 61 so as to connect the first space 105 and the second space 106. The opening 671 of the discharge valve passage 67 on the first space 105 side is formed outside the recess 65 radially. An opening 672 of the discharge valve passage 67 on the second space 106 side is formed at the bottom of the recess 66. In the present embodiment, two discharge valve passages 67 are formed in the valve seat body 61. Further, the two discharge valve passages 67 are formed so as to sandwich the axis of the valve seat body 61 and to be inclined with respect to the axis.

The relief valve passage 68 is formed in the valve seat body 61 so as to connect the second space 106 and the first space 105 and not communicate with the discharge valve passage 67. In the present embodiment, the relief valve passage 68 has a first passage 681 and a second passage 682. The first passage 681 extends so as to be orthogonal to the axis of the valve seat main body 61, and is formed so that both ends open to the outer wall of the valve seat main body 61. Thereby, the first passage 681 communicates with the cylindrical space 107.
The second passage 682 extends along the axis of the valve seat body 61, and has one end connected to the center of the first passage 681. The second passage 682 has an opening 683 at the other end formed in the bottom 651 of the recess 65 (see FIG. 4).
The discharge valve seat 611 is formed in an annular shape at the outer edge of the recess 66. That is, the discharge valve seat 611 is formed in an annular shape around the opening 672 of the discharge valve passage 67 of the valve seat body 61 on the second space 106 side.

The relief valve seat 612 is formed annularly around the opening 683 of the relief valve passage 68 of the valve seat body 61 on the first space 105 side. Here, the relief valve seat 612 is tapered so as to approach the axis of the relief valve seat 612 from the first space 105 to the second space 106 (see FIG. 4).
The valve seat portion cylindrical portion 62 is formed so as to extend in a tubular shape from the outer edge of the end surface of the valve seat portion main body 61 on the first space 105 side toward the pressurizing chamber 103 side. Here, the outer wall of the valve seat cylindrical portion 62 is in contact with the inner wall of the union 51.

  The valve seat projection 63 is formed in an annular shape so as to project radially outward from an end of the valve seat cylinder 62 opposite to the valve seat body 61. Here, the valve seat protrusion 63 is sandwiched between the step 114 of the upper housing 11 and the end of the union 51 on the side of the pressurizing chamber 103. Thereby, the relative movement of the valve seat portion 60 in the axial direction with respect to the upper housing 11 is restricted.

  The discharge valve member 70 is formed in a substantially disk shape with a metal such as stainless steel, for example. The discharge valve member 70 is provided in the second space 106 so as to be able to contact the discharge valve seat 611, and opens and closes the discharge valve passage 67 when it is separated from the discharge valve seat 611 or comes into contact with the discharge valve seat 611.

  In the present embodiment, the discharge valve device 50 further includes a holder 72. The holder 72 is formed of a metal such as stainless steel, for example, and is provided inside the union 51 and in the second space 106. The holder 72 has a holder bottom 73, a holder cylinder 74, and a holder protrusion 75.

  The holder bottom 73 is formed in a substantially disk shape, and has a hole 731 at the center which penetrates in the thickness direction. The holder tubular portion 74 is formed to extend in a tubular shape from the outer edge of the holder bottom 73 toward the pressurizing chamber 103. A cylindrical space 108, which is a substantially cylindrical space, is formed between the outer wall of the holder cylindrical portion 74 and the inner wall of the union 51. The projection 64 of the valve seat body 61 and the discharge valve member 70 are located inside the end of the holder cylinder 74 opposite to the holder bottom 73. The inner wall of the end of the holder cylinder 74 opposite to the holder bottom 73 is tapered to correspond to the shape of the outer wall of the projection 64. A cylindrical space 109, which is a cylindrical space, is formed between the outer wall of the protrusion 64 and the inner wall of the holder cylinder 74. The cylindrical space 109 and the cylindrical space 107 communicate with each other via a space between the holder 72 and the valve seat body 61 (see FIG. 3).

The holder cylinder 74 has a plurality of holes 741 formed to connect the inner wall and the outer wall near the end opposite to the holder bottom 73. Thereby, the hole 741 communicates with the cylindrical space 108 and the cylindrical space 109. In the present embodiment, for example, four holes 741 are formed at equal intervals in the circumferential direction of the holder cylinder 74. Note that, with the above configuration, the relief valve passage 68 communicates with the cylindrical space 108 via the cylindrical space 107, the cylindrical space 109, and the hole 741.
The holder cylinder 74 has a step 742 on the inner wall of the hole 741 on the holder bottom 73 side. The step portion 742 is formed in a substantially annular shape so that the outer edge of the discharge valve member 70 can abut.

  The holder protrusion 75 is formed in an annular shape so as to protrude radially outward from the end of the holder cylinder 74 opposite to the holder bottom 73. The holder 72 is provided such that the holder protrusion 75 is fitted to the inner wall of the union 51 and abuts on the step 52 of the union 51. Thereby, the relative movement of the holder 72 in the axial direction with respect to the union 51 is restricted.

  The discharge valve urging member 71 is, for example, a coil spring, and is provided on the side of the discharge valve member 70 opposite to the valve seat 60. The discharge valve urging member 71 is provided inside the holder cylinder 74 so that one end thereof contacts the discharge valve member 70 and the other end thereof contacts the holder bottom 73 of the holder 72. The discharge valve urging member 71 urges the discharge valve member 70 toward the discharge valve seat 611. As a result, the discharge valve member 70 is pressed against the discharge valve seat 611.

  The discharge valve member 70 is provided to be able to reciprocate in the axial direction inside the holder 72. The movement of the discharge valve member 70 toward the holder bottom 73 is restricted by contacting the step 742 of the holder 72. Therefore, the discharge valve member 70 is axially movable between the discharge valve seat 611 and the step portion 742.

  The relief valve member 80 is formed of a metal such as stainless steel, for example. In the present embodiment, the hardness of the relief valve member 80 is set equal to the hardness of the valve seat 60. The relief valve member 80 has a relief valve main body 81, a relief valve seat portion 82, a valve member protrusion 83, and a fuel guide portion 84.

  The relief valve main body 81 is formed in a rod shape, more specifically, in a substantially columnar shape. The relief valve member 80 has an end 811 which is one end of the relief valve main body 81 located inside the concave portion 65 of the valve seat main body 61, and the other end of the relief valve main body 81 faces the pressurizing chamber 103. Is provided in the first space 105. A large-diameter portion 812 is formed on the pressurizing chamber 103 side of the end 811 of the relief valve main body 81. The end portion 811 and the large diameter portion 812 are formed in a substantially columnar shape. The outer diameter of the large diameter portion 812 is set to be larger than the outer diameter of the end 811 (see FIG. 4). The outer diameter of the end 811 is slightly smaller than the inner diameter of the cylindrical portion 652 of the recess 65. Therefore, a substantially cylindrical gap is formed between the end 811 and the cylindrical portion 652.

  The relief valve seat portion 82 is formed integrally with the relief valve main body 81 at one end (end portion 811) of the relief valve main body 81 so as to be able to contact the relief valve seat 612. More specifically, the relief valve seat portion 82 is formed so as to project from the center of the end 811 of the relief valve main body 81 to the second space 106 side in a substantially columnar shape. The relief valve seat portion 82 has a first tapered surface 821 and a second tapered surface 822 on the second space 106 side. The first tapered surface 821 is formed in a tapered shape so as to approach the axis of the relief valve seat portion 82 from the first space 105 side toward the second space 106 side. The second tapered surface 822 is formed on the first tapered surface 821 on the side of the second space 106 so as to be connected to the first tapered surface 821. The second tapered surface 822 is tapered so as to approach the axis of the relief valve seat portion 82 from the first space 105 side toward the second space 106 side. Here, the angle formed by the virtual straight line extending along the first tapered surface 821 and the axis of the relief valve seat portion 82 is formed by the virtual straight line extending along the second tapered surface 822 and the axis of the relief valve seat portion 82. Smaller than the corner (see FIG. 4). Therefore, an edge is formed (boundary) between the first tapered surface 821 and the second tapered surface 822.

In the present embodiment, the angle formed between the virtual straight line extending along the first tapered surface 821 and the axis of the relief valve seat portion 82 is defined by the virtual straight line extending along the relief valve seat 612 and the axis of the relief valve seat 612. It is set almost the same as the corner. Therefore, the first tapered surface 821 of the relief valve member 80 can contact the relief valve seat 612 by surface contact. When the first tapered surface 821 and the relief valve seat 612 are in surface contact, the relief valve seat portion 82 and the relief valve seat 612 have a coaxial relationship. As described above, the relief valve member 80 and the relief valve seat 612 are centered by the first tapered surface 821 and the relief valve seat 612.
As shown in FIG. 4, an intermediate chamber 654 which is an annular space is formed between the relief valve seat 82 and the bottom 651 of the recess 65 and the cylindrical portion 652.
The valve member projecting portion 83 is formed in an annular shape so as to project radially outward from the pressure chamber 103 side of the large diameter portion 812 of the relief valve main body 81.

The fuel guide portion 84 is provided at the other end of the relief valve main body 81, that is, at the end on the pressurizing chamber 103 side, and is formed integrally with the relief valve main body 81. The fuel guide portion 84 is formed such that the outer wall is away from the shaft as it goes from the pressurizing chamber 103 side to the valve seat portion 60 side. Therefore, when the fuel flowing from the pressurizing chamber 103 side to the valve seat portion 60 side flows along the outer wall of the fuel guide portion 84, the fuel is guided to flow in a radially outward direction of the relief valve main body 81.
The relief valve member 80 is provided in the first space 105 so as to be able to reciprocate in the axial direction of the relief valve main body 81.

  In the present embodiment, the opening 671 of the discharge valve passage 67 on the first space 105 side passes through the outermost part of the outer wall of the relief valve member 80 (the outer wall of the valve member projecting portion 83) and extends in the axial direction of the relief valve main body 81. And is formed outside a virtual cylindrical surface C1 extending in a cylindrical shape (see FIG. 3).

  The relief valve urging member 89 is, for example, a coil spring, and the relief valve main body 81 is inserted inside. That is, the relief valve urging member 89 is provided radially outside the relief valve main body 81. One end of the relief valve urging member 89 is in contact with the wall surface of the valve member projection 83 on the side of the pressurizing chamber 103.

  The support portion 90 is formed of a metal such as stainless steel, for example, and is provided in the first space 105. In the present embodiment, the hardness of the support portion 90 is set lower than the hardness of the valve seat portion 60 and the relief valve member 80. The support portion 90 has a support portion main body 91, a support portion tubular portion 92, and a spring seat member 93.

  The support portion main body 91 is formed in a substantially disk shape. The support portion main body 91 has a guide hole 94. The guide hole 94 is formed to penetrate the center of the support portion main body 91 in the thickness direction. The relief valve main body 81 of the relief valve member 80 is inserted into the guide hole 94. The guide hole 94 has an inner diameter substantially equal to the other end of the relief valve main body 81, that is, the outer diameter of the end on the pressurizing chamber 103 side, or the outer diameter of the end of the relief valve main body 81 on the pressurizing chamber 103 side. It is formed slightly larger. Therefore, the inner wall of the guide hole 94 can slide with the outer wall on the other end side of the relief valve main body 81.

The support portion tubular portion 92 is formed so as to extend from the outer edge of the support portion main body 91 to the valve seat portion 60 side in a substantially cylindrical shape. The support portion 90 is provided such that an outer wall of an end portion of the support portion cylindrical portion 92 opposite to the support portion main body 91 is fitted to an inner wall of the valve seat portion cylindrical portion 62. Accordingly, the support portion 90 is provided so as not to be relatively movable with respect to the valve seat portion 60, and the support portion main body 91 supports the relief valve member 80 so that the relief valve member 80 can reciprocate in the axial direction. As described above, the supporting portion main body 91 of the supporting portion 90 slidably supports the outer wall of the relief valve main body 81 so as to guide the reciprocating movement of the relief valve member 80 in the axial direction.
A cylindrical space 110, which is a substantially cylindrical space, is formed between an outer wall of an end of the support portion cylindrical portion 92 on the support portion main body 91 side and an inner wall of the upper housing 11 forming the discharge hole portion 112. I have.

  The support portion tubular portion 92 has a plurality of holes 921 formed to connect the inner wall and the outer wall. Thus, the hole 921 communicates with the space inside the support portion tubular portion 92 and the tubular space 110. In the present embodiment, for example, four holes 921 are formed at equal intervals in the circumferential direction of the support portion tubular portion 92.

  The spring seat member 93 is formed in a substantially disc shape separately from the support portion main body 91 and the support portion tubular portion 92. The spring seat member 93 is provided on the valve seat section 60 side of the support section main body 91. The spring seat member 93 has a hole in the center in the plate thickness direction, and an end of the relief valve main body 81 on the pressurizing chamber 103 side is inserted into the hole.

  The other end of the relief valve urging member 89 is in contact with the surface of the spring seat member 93 on the valve seat portion 60 side. The relief valve urging member 89 presses the spring seat member 93 against the support portion main body 91 and urges the relief valve member 80 toward the relief valve seat 612. Thereby, the first tapered surface 821 of the relief valve seat portion 82 is pressed against the relief valve seat 612.

  The discharge valve member 70 is configured such that the pressure of the fuel in the first space 105 is equal to the sum of the pressure of the fuel in the second space 106 and the urging force of the discharge valve urging member 71 (valve opening pressure of the discharge valve member 70). When it becomes larger, it is separated from the discharge valve seat 611 and opens. At this time, the pressurizing chamber 103 includes the discharge hole 132, the cylindrical space 110, the hole 921, the space inside the support portion tube 92 and the valve seat tube 62, the discharge valve passage 67, the recess 66, and the hole 741. The union 51 communicates with the space inside the end on the pipe 6 side via the cylindrical space 108. Thereby, the fuel on the pressurizing chamber 103 side, that is, the first space 105 side is discharged to the pipe 6 side, that is, the second space 106 side via the discharge valve seat 611. The valve opening pressure of the discharge valve member 70 can be set by adjusting the urging force of the discharge valve urging member 71.

  On the other hand, the relief valve member 80 is configured such that the fuel pressure in the second space 106 is the sum of the fuel pressure in the first space 105 and the urging force of the relief valve urging member 89 (the valve opening pressure of the relief valve member 80). ), The valve is separated from the relief valve seat 612 and opened. At this time, the space inside the end of the union 51 on the side of the pipe 6 includes a cylindrical space 108, a hole 741, a cylindrical space 109, a cylindrical space 107, a first passage 681 of the relief valve passage 68, and a second passage. 682, the recess 65, the space inside the valve seat cylinder 62 and the support cylinder 92, the hole 921, the cylindrical space 110, and the discharge hole 132 communicate with the pressurizing chamber 103. Accordingly, the fuel on the pipe 6 side, that is, the fuel on the second space 106 side is returned to the pressurizing chamber 103 side, that is, the first space 105 side via the relief valve seat 612. As a result, it is possible to suppress the fuel pressure on the second space 106 side from becoming abnormally high. The valve opening pressure of the relief valve member 80 can be set by adjusting the urging force of the relief valve urging member 89.

Further, in the present embodiment, the urging force of the relief valve urging member 89 is set to be larger than a degree that the relief valve urging member 89 does not come out of the end portion 811 recess 65 of the relief valve member 80. Therefore, the end 811 of the relief valve member 80 is prevented from falling out of the recess 65.
As described above, the discharge valve device 50 of the present embodiment is a relief valve integrated discharge valve device having both a function as a discharge valve and a function as a relief valve.

Next, the operation of the high-pressure pump 1 of the present embodiment will be described with reference to FIG.
"Inhalation process"
When the supply of power to the coil 45 of the electromagnetic drive unit 40 is stopped, the suction valve member 32 is urged toward the pressurizing chamber 103 by the needle urging member 37 and the needle 35. Therefore, the suction valve member 32 is separated from the suction valve seat 311, that is, is opened. When the plunger 20 moves toward the cam 5 in this state, the volume of the pressurizing chamber 103 increases, and the fuel in the suction passage 101 is sucked into the pressurizing chamber 103.

"Measuring process"
When the plunger 20 moves to the side opposite to the cam 5 in a state where the suction valve member 32 is opened, the volume of the pressurizing chamber 103 decreases, and the fuel in the pressurizing chamber 103 is released from the fuel gallery 100 in the suction passage 101. Returned to the side. When electric power is supplied to the coil 45 during the metering process, the movable core 43 is sucked together with the needle 35 toward the fixed core 44, and the suction valve member 32 contacts the suction valve seat 311 to close the valve. When the plunger 20 moves to the side opposite to the cam 5, the suction valve member 32 is closed to shut off the space between the pressure chamber 103 side of the suction passage 101 and the fuel gallery 100 side. The amount of fuel returned to the fuel gallery 100 side of the suction passage 101 is adjusted. As a result, the amount of fuel pressurized in the pressurizing chamber 103 is determined. When the intake valve member 32 is closed, the metering step of returning fuel from the pressurizing chamber 103 to the fuel gallery 100 side of the intake passage 101 ends.

"Pressure process"
When the plunger 20 further moves to the opposite side to the cam 5 with the suction valve member 32 closed, the volume of the pressurizing chamber 103 decreases, and the fuel in the pressurizing chamber 103 is compressed and pressurized. When the pressure of the fuel in the pressurizing chamber 103 becomes equal to or higher than the opening pressure of the discharge valve member 70, the discharge valve member 70 opens, and the fuel moves from the pressurizing chamber 103 to the pipe 6 side, that is, to the second space 106 side. Discharged.

  When the supply of power to the coil 45 is stopped and the plunger 20 moves toward the cam 5, the suction valve member 32 opens again. Thus, the pressurizing step of pressurizing the fuel is completed, and the suction step in which fuel is sucked from the fuel gallery 100 side of the suction passage 101 to the pressurizing chamber 103 side is restarted.

  The high-pressure pump 1 pressurizes and discharges the sucked fuel in the fuel tank 2 and supplies it to the fuel rail 7 by repeating the above-mentioned “suction process”, “metering process”, and “pressurizing process”. The amount of fuel supplied from the high-pressure pump 1 to the fuel rail 7 is adjusted by controlling the timing of supplying power to the coil 45 of the electromagnetic drive unit 40 and the like.

  For example, if the state in which the supply of power to the coil 45 is stopped continues for a predetermined period, the suction valve member 32 maintains the open state, so that the fuel is not pressurized in the pressurizing chamber 103, and the fuel becomes high pressure. It is not supplied from the pump 1 to the fuel rail 7. Further, even when the suction valve member 32 is kept in the open state for some reason such as the sticking of the suction valve member 32, the fuel is not pressurized in the pressurizing chamber 103, and the fuel is supplied from the high-pressure pump 1. Not supplied to rail 7.

  On the other hand, for example, when the supply of electric power to the coil 45 continues for a predetermined period, the suction valve member 32 is closed in the pressurizing step, so that the fuel is pressurized in the pressurizing chamber 103 and the fuel is supplied from the high-pressure pump 1. The fuel is supplied to the rail 7 and the pressure of the fuel in the second space 106, the pipe 6, and the fuel rail 7 increases. Further, even when the suction valve member 32 maintains the valve closed state for some reason such as the sticking of the suction valve member 32, the fuel is pressurized in the pressurizing chamber 103 and supplied to the fuel rail 7 from the high-pressure pump 1. As a result, the pressure of the fuel in the second space 106, the pipe 6, and the fuel rail 7 increases.

Next, the operation of the discharge valve device 50 of the high-pressure pump 1 according to the present embodiment will be described.
As shown in FIG. 5, when the pressure of the fuel in the first space 105 becomes larger than the valve opening pressure of the discharge valve member 70, the discharge valve member 70 separates from the discharge valve seat 611 and opens. At this time, the fuel in the pressurizing chamber 103 is discharged from the discharge hole 132, the cylindrical space 110, the hole 921, the space inside the support portion cylindrical portion 92 and the valve seat cylindrical portion 62, the discharge valve passage 67, the concave portion 66, Through the hole 741 and the cylindrical space 108, the union 51 can flow toward the space inside the end on the pipe 6 side.

  In the present embodiment, the support portion main body 91 of the support portion 90 slidably supports the outer wall of the relief valve body 81 so as to guide the axial movement of the relief valve member 80. Therefore, even if the fuel discharged from the pressurizing chamber 103 flows around the relief valve member 80, the relief valve seat portion 82 of the relief valve member 80 may move or vibrate in the radial direction relative to the relief valve seat 612. Is suppressed. Thereby, wear of the relief valve seat 612 or the relief valve seat portion 82 can be suppressed.

  In the present embodiment, the relief valve seat portion 82 is formed integrally with the relief valve main body 81. Therefore, the relief valve seat portion 82 and the relief valve main body 81 do not move relative to each other. Therefore, for example, the position of the relief valve seat portion 82 is stabilized as compared with a configuration in which the relief valve main body 81 and the relief valve seat portion 82 are formed separately.

  Further, in the present embodiment, the opening 671 of the discharge valve passage 67 on the first space 105 side passes through the outermost portion (outer wall of the valve member protrusion 83) of the outer wall of the relief valve member 80, and the opening 671 of the relief valve main body 81. It is formed outside a virtual cylindrical surface C1 that extends cylindrically in the axial direction. Therefore, when the fuel is discharged from the pressurizing chamber 103, the fuel around the relief valve body 81 smoothly flows into the discharge valve passage 67 without being blocked by the valve member projection 83 of the relief valve member 80. be able to.

  When the discharge valve member 70 is opened, the fuel flowing from the pressurizing chamber 103 toward the valve seat 60 near the fuel guide portion 84 of the relief valve member 80 is released by the fuel guide portion 84 through the relief valve body. It is guided to flow outward in the radial direction of 81. Thereby, it is possible to suppress the fuel from entering between the guide hole portion 94 of the support portion 90 and the relief valve main body 81. Therefore, the occurrence of cavitation erosion between the guide hole 94 and the relief valve main body 81 can be suppressed, and the erosion of the guide hole 94 of the support portion 90 can be suppressed.

  As shown in FIG. 6, when the pressure of the fuel in the second space 106 becomes larger than the valve opening pressure of the relief valve member 80, the relief valve member 80 separates from the relief valve seat 612 and opens. At this time, the fuel in the space inside the end of the union 51 on the side of the pipe 6 passes through the cylindrical space 108, the hole 741, the cylindrical space 109, the cylindrical space 107, the first passage 681 of the relief valve passage 68, The gas can flow toward the pressurizing chamber 103 via the space inside the second passage 682, the concave portion 65, the valve seat cylinder 62 and the support cylinder 92, the hole 921, the cylindrical space 110, and the discharge hole 132. Becomes

  In the present embodiment, the support portion main body 91 of the support portion 90 slidably supports the outer wall of the relief valve main body 81 so as to guide the reciprocating movement of the relief valve member 80 in the axial direction. Thus, when the relief valve member 80 opens, the movement of the relief valve member 80 toward the pressurizing chamber 103 is stabilized.

  Further, in the present embodiment, when the relief valve seat portion 82 is separated from the relief valve seat 612, the fuel in the relief valve passage 68 flows into the intermediate chamber 654 (see FIG. 4). Thereby, the pressure in the intermediate chamber 654 increases quickly, and the relief valve member 80 can be quickly moved to the pressurizing chamber 103 side. The fuel in the intermediate chamber 654 flows toward the pressurizing chamber 103 through the space between the cylindrical portion 652 and the tapered portion 653 of the concave portion 65 and the end 811 and the large-diameter portion 812 of the relief valve main body 81.

As described above, (1) In the present embodiment, the pump body 10 has the pressurizing chamber 103 for pressurizing the fuel, and the discharge passage 102 through which the fuel pressurized and discharged in the pressurizing chamber 103 flows.
The valve seat portion 60 has a valve seat portion main body 61, a discharge valve passage 67, a relief valve passage 68, a discharge valve seat 611, and a relief valve seat 612.

  The valve seat body 61 is formed in the discharge passage 102 so as to divide the discharge passage 102 into a first space 105 which is a space on the pressurizing chamber 103 side and a second space 106 which is a space on the opposite side to the pressurizing chamber 103. Provided. The discharge valve passage 67 is formed in the valve seat body 61 so as to connect the first space 105 and the second space 106. The relief valve passage 68 is formed in the valve seat body 61 so as to connect the second space 106 and the first space 105 and not communicate with the discharge valve passage 67. The discharge valve seat 611 is formed in an annular shape around the opening 672 on the second space 106 side of the discharge valve passage 67 of the valve seat body 61. The relief valve seat 612 is formed in an annular shape around the opening 683 of the relief valve passage 68 of the valve seat body 61 on the first space 105 side.

The discharge valve member 70 is provided in the second space 106 so as to be able to contact the discharge valve seat 611, and opens and closes the discharge valve passage 67 when it is separated from the discharge valve seat 611 or comes into contact with the discharge valve seat 611.
The discharge valve urging member 71 urges the discharge valve member 70 toward the discharge valve seat 611.
The relief valve member 80 has a relief valve main body 81 and a relief valve seat 82.
The relief valve main body 81 is formed in a rod shape. The relief valve seat portion 82 is formed integrally with the relief valve main body 81 at one end of the relief valve main body 81 so as to be able to contact the relief valve seat 612. The relief valve member 80 is provided in the first space 105 so as to be able to reciprocate in the axial direction.
The relief valve urging member 89 urges the relief valve member 80 toward the relief valve seat 612.
The support part 90 has a support part main body 91 that slidably supports the outer wall of the relief valve main body 81 so as to guide the reciprocating movement of the relief valve member 80 in the axial direction.

  In the present embodiment, the support portion main body 91 of the support portion 90 slidably supports the outer wall of the relief valve main body 81 so as to guide the reciprocating movement of the relief valve member 80 in the axial direction. Therefore, even if the fuel discharged from the pressurizing chamber 103 of the high-pressure pump 1 flows around the relief valve member 80, the relief valve seat portion 82 of the relief valve member 80 moves relative to the relief valve seat 612 in the radial direction or Vibration is suppressed. Thereby, wear of the relief valve seat 612 or the relief valve seat portion 82 can be suppressed. Accordingly, it is possible to suppress a change over time of the valve opening pressure of the relief valve member 80.

  In the present embodiment, the relief valve seat portion 82 is formed integrally with the relief valve main body 81. Therefore, the relief valve seat portion 82 and the relief valve main body 81 do not move relative to each other. Therefore, for example, the position of the relief valve seat portion 82 is stabilized as compared with a configuration in which the relief valve main body 81 and the relief valve seat portion 82 are formed separately. Therefore, wear of the relief valve seat 612 or the relief valve seat portion 82 can be further suppressed.

  (2) In the present embodiment, the support portion 90 slidably supports the other end of the relief valve main body 81, that is, the outer wall at the end on the pressurizing chamber 103 side. Therefore, when the relief valve member 80 reciprocates, the tilt of the axis of the relief valve member 80 can be effectively suppressed. Further, since the sliding portion between the inner wall of the support portion 90 and the outer wall of the relief valve main body 81 is located far from the relief valve seat 612, the inner wall of the support portion 90 and the outer wall of the relief valve main body 81 are worn by sliding. Even if abrasion powder is generated, it is possible to suppress the abrasion powder from being caught between the relief valve seat 612 and the relief valve seat portion 82.

  (3) In the present embodiment, the valve seat main body 61 has the concave portion 65 formed so as to be concave from the end surface on the first space 105 side to the second space 106 side. The relief valve seat 612 is formed at the bottom 651 of the recess 65. Therefore, the relief valve member 80 is provided such that the end 811 on the relief valve seat 612 side is located in the recess 65. A variable volume intermediate chamber 654 is formed between the end 811 of the relief valve member 80 and the recess 65. When the relief valve seat portion 82 separates from the relief valve seat 612, the pressure in the intermediate chamber 654 quickly increases, so that the relief valve member 80 can be quickly moved in the pressure chamber 103 side, that is, in the valve opening direction. it can.

  (4) In the present embodiment, the relief valve seat 612 is formed in a tapered shape such that the inner diameter decreases from the first space 105 side toward the second space 106 side. Thus, when the relief valve member 80 comes into contact with the relief valve seat 612, the relief valve member 80 is aligned with the relief valve seat 612.

  (5) In the present embodiment, the first tapered surface 821 and the second tapered surface 822 of the relief valve seat portion 82 are tapered so that the inner diameter decreases from the first space 105 side toward the second space 106 side. Is formed. Therefore, the first tapered surface 821 of the relief valve seat portion 82 can be brought into contact with the tapered relief valve seat 612 by surface contact. Therefore, the surface pressure between the relief valve seat portion 82 and the relief valve seat 612 can be reduced, and wear of the relief valve seat 612 or the relief valve seat portion 82 can be effectively suppressed.

  (7) In the present embodiment, the opening 671 of the discharge valve passage 67 on the first space 105 side passes through the outermost portion of the outer wall of the relief valve member 80 (the outer wall of the valve member projecting portion 83), and the relief valve. It is formed outside a virtual cylindrical surface C1 that extends cylindrically in the axial direction of the main body 81. Therefore, when the fuel is discharged from the pressurizing chamber 103, the fuel around the relief valve body 81 smoothly flows into the discharge valve passage 67 without being blocked by the valve member projection 83 of the relief valve member 80. be able to. Therefore, the fuel can be smoothly discharged from the pressurizing chamber 103 toward the pipe 6 and the fuel rail 7.

  (8) In the present embodiment, the valve seat portion 60 has a valve seat portion tubular portion 62 that extends from the valve seat portion main body 61 to the first space 105 side in a tubular manner. The support portion 90 has a support portion tubular portion 92 that extends from the support portion main body 91 toward the second space 106 in a tubular shape and fits on the inner wall of the valve seat portion tubular portion 62. As described above, the support portion 90 that slidably supports the relief valve member 80 and the valve seat portion 60 on which the relief valve seat 612 is formed are provided integrally so as to be relatively immovable. Therefore, the position where the relief valve seat portion 82 of the relief valve member 80 abuts on the relief valve seat 612 can be suppressed from becoming unstable. Thus, wear of the relief valve seat 612 or the relief valve seat portion 82 can be effectively suppressed.

  (9) In the present embodiment, the relief valve member 80 has a valve member projection 83 formed to project radially outward from the relief valve main body 81. The relief valve biasing member 89 is provided such that one end thereof contacts the valve member projecting portion 83 and the other end thereof contacts the support portion 90.

  Further, as described above, by fitting the valve seat portion cylindrical portion 62 and the support portion tubular portion 92, the valve seat portion 60, the relief valve member 80, the relief valve urging member 89, and the support portion 90 are unitized. can do. Therefore, it becomes easy to set the urging force of the relief valve urging member 89 to a desired magnitude. Further, the discharge valve device 50 including the relief valve member 80 can be easily assembled to the pump body 10 of the high-pressure pump 1.

  (10) In the present embodiment, the relief valve biasing member 89 is a coil spring formed in a cylindrical shape, and is provided on the radial outside of the relief valve main body 81. Therefore, the relief valve urging member 89 can stably urge the relief valve member 80 toward the relief valve seat 612 in the axial direction. Thereby, when the relief valve member 80 reciprocates in the axial direction, the inclination of the shaft is suppressed. As a result, wear of the relief valve seat 612 or the relief valve seat portion 82 can be more effectively suppressed.

  (11) In the present embodiment, the pump body 10 has the cylindrical union 51 that forms the discharge passage 102 inside, and the upper housing 11 into which one end of the union 51 is inserted. The valve seat portion 60 has a valve seat portion projecting portion 63 that is formed so as to project radially outward and is sandwiched between one end of the union 51 and the step portion 114 of the upper housing 11. Thus, the axial movement of the valve seat portion 60 relative to the upper housing 11 and the union 51 is restricted.

(2nd Embodiment)
FIG. 7 shows a part of a high-pressure pump according to a second embodiment of the present invention. The second embodiment differs from the first embodiment in the shape of the relief valve seat portion of the relief valve member 80.

  In the second embodiment, the relief valve seat portion 85 is formed in a spherical shape. Therefore, the relief valve member 80 can contact the relief valve seat portion 85 with the relief valve seat 612 by linear contact. When the relief valve seat portion 82 and the relief valve seat 612 are in line contact, the relief valve seat portion 82 and the relief valve seat 612 have a coaxial relationship. As described above, the relief valve member 80 and the relief valve seat 612 are centered by the relief valve seat portion 85 and the relief valve seat 612.

  As described above, (6) in the present embodiment, the relief valve seat portion 85 is formed in a spherical shape. Therefore, the relief valve seat portion 85 and the tapered relief valve seat 612 can be brought into contact with each other by linear contact. Therefore, the surface pressure between the relief valve seat portion 85 and the relief valve seat 612 can be increased, and when the relief valve member 80 is closed, the space between the relief valve seat portion 85 and the relief valve seat 612 can be kept liquid-tight. it can. In the present embodiment, since the relief valve seat portion 85 is formed in a spherical shape, even when the surface pressure between the relief valve seat portion 85 and the relief valve seat 612 is large, the relief valve seat portion 85 and the relief valve seat portion 612 can be used. 612 can be suppressed.

(Other embodiments)
In the above-described embodiment, an example has been described in which the support portion main body 91 of the support portion 90 slidably supports the other end side of the relief valve main body 81, that is, the outer wall of the end portion on the pressurizing chamber 103 side. On the other hand, in another embodiment of the present invention, the support portion main body 91 of the support portion 90 may slidably support any position in the axial direction of the relief valve main body 81.

Further, in another embodiment of the present invention, the valve seat portion main body 61 may not have the concave portion 65 that is recessed from the end surface on the first space 105 side to the second space 106 side. In this case, the relief valve seat 612 is formed on the end surface of the valve seat body 61 on the first space 105 side.
Further, in another embodiment of the present invention, the relief valve seat 612 is not limited to a tapered shape, and may be formed in a flat shape.
In another embodiment of the present invention, the relief valve seat portion is not limited to a tapered shape or a spherical shape, and may be formed in any shape such as a flat shape.

  In the above-described embodiment, the opening 671 of the discharge valve passage 67 on the first space 105 side extends through the outermost portion of the outer wall of the relief valve member 80 and extends in a cylindrical shape in the axial direction of the relief valve main body 81. The example formed outside the cylindrical surface C1 was shown. On the other hand, in another embodiment of the present invention, the opening 671 of the discharge valve passage 67 on the first space 105 side may be formed so that at least a part thereof is located inside the virtual cylindrical surface C1. The number of the discharge valve passages 67 is not limited to two, but may be one, or three or more.

  Further, in the above-described embodiment, an example has been described in which the support portion tubular portion 92 of the support portion 90 is fitted to the inner wall of the valve seat portion tubular portion 62 of the valve seat portion 60. On the other hand, in another embodiment of the present invention, the support portion tubular portion 92 may be fitted to the outer wall of the valve seat portion tubular portion 62.

  Further, in another embodiment of the present invention, the valve seat portion 60 may not have the valve seat portion tubular portion 62. Further, the support portion 90 may not have the support portion tubular portion 92. That is, the valve seat portion 60 and the support portion 90 need not be fitted to each other. In this case, it is conceivable to provide the support portion 90 (support portion main body 91) by fitting it to the inner wall of the upper housing 11 forming the discharge hole portion 112.

  In another embodiment of the present invention, the relief valve member 80 may not have the valve member projection 83. In this case, it is conceivable to provide the relief valve urging member 89 so as to abut on an end of the relief valve member 80 opposite to the relief valve seat portion 82 or a predetermined position in the axial direction of the relief valve member 80. Can be Further, in another embodiment of the present invention, the relief valve urging member 89 is not limited to a coil spring, and may be formed by, for example, a plate spring or the like.

In another embodiment of the present invention, the union 51 may be formed integrally with the upper housing 11. In this case, the valve seat protrusion 63 of the valve seat 60 may be omitted.
In another embodiment of the present invention, at least two of the cylinder, the upper housing, and the lower housing may be integrally formed.

  Further, in another embodiment of the present invention, the suction valve device may constitute a normally closed type (normally closed type) valve device together with the electromagnetic drive unit. Further, if the suction valve device constitutes a normally closed type valve device, the electromagnetic drive unit may not be provided.

Further, in another embodiment of the present invention, a configuration in which the pulsation damper is not provided inside the cover may be adopted. Further, a configuration without a cover may be employed. In a case where the cover member is not provided, it is conceivable to directly supply the fuel to the suction passage of the pump body.
Further, in another embodiment of the present invention, the high-pressure pump may be used as a fuel pump that discharges fuel toward a device other than the engine of the vehicle.
As described above, the present invention is not limited to the above embodiment, and can be implemented in various forms without departing from the gist of the present invention.

DESCRIPTION OF SYMBOLS 1 High pressure pump, 10 pump body, 102 discharge passage, 103 pressurization chamber, 105 first space, 106 second space, 60 valve seat, 61 valve seat body, 67 discharge valve passage, 68 relief valve passage, 681 1 passage (relief valve passage), 682 second passage (relief valve passage), 611 discharge valve seat, 612 relief valve seat, 70 discharge valve member, 71 discharge valve biasing member, 80 relief valve member, 81 relief valve body, 82, 85 relief valve seat, 89 relief valve biasing member, 90 support, 91 support body

Claims (1)

A pump body (10) having a pressurizing chamber (103) for pressurizing the fuel, and a discharge passage (102) through which the fuel pressurized and discharged in the pressurizing chamber flows.
A valve seat body (61) provided in the discharge passage, a relief valve passage (68, 681, 682) formed in the valve seat body and returning fuel in the discharge passage to the pressurizing chamber side; A valve seat portion (60) having a relief valve seat (612) formed annularly around an opening of the relief valve passage of the valve seat portion body on the side of the pressurizing chamber;
A relief valve body (81), and a relief valve seat portion (82) integrally formed with the relief valve body at one end of the relief valve body so as to be able to abut on the relief valve seat; A relief valve member (80) provided inside the valve seat so as to be able to reciprocate;
A relief valve biasing member (89) for biasing the relief valve member toward the relief valve seat.
The relief valve seat portion has a first tapered surface (821) and a second tapered surface (822) connected to the first tapered surface and located on a side opposite to the pressurizing chamber with respect to the first tapered surface. Has,
The high-pressure pump (1), wherein an inclination angle of the first tapered surface with respect to the relief valve seat is smaller than an inclination angle of the second tapered surface with respect to the relief valve seat.

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