JP2013050072A - High-pressure pump - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a high-pressure pump, in which deformation of a member constituting a valve seat can be suppressed.SOLUTION: A valve body 60 has a tube part 61, a flange part 62, a first valve seat forming part 63 and a second valve seat forming part 64, a discharge valve seat 66, and a discharge valve passage 68. The tube part 61 is accommodated inside one end of a tube member 50. The flange part 62 extends to a radial outer direction from an end of a pressurizing chamber 31 side of the tube part 61 and is sandwiched between the one end of the tube member 50 and a stepped surface 454 of a housing 40. The first valve seat forming part 63 and the second valve seat forming part 64 blocks an end on the opposite side from the pressurizing chamber 31 of the tube part 61. The discharge valve seat 66 is formed on a wall surface on the opposite side from the tube part 61 of the second valve seat forming part 64. A discharge valve member 71 is provided to be seatable on the discharge valve seat 66.

Description

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

  2. Description of the Related Art Conventionally, a high pressure pump is known that draws fluid into a pressurizing chamber by reciprocating movement of a plunger, pressurizes and discharges the fluid. For example, Patent Document 1 discloses a high-pressure pump that pressurizes and discharges fuel as a fluid and supplies the fuel to an internal combustion engine. In this high-pressure pump, a cylindrical member that forms a valve seat of a discharge valve that intermittently discharges fuel is press-fitted into the inner wall of the housing of the high-pressure pump. For this reason, a force in the radially inward direction acts on the member forming the valve seat of the discharge valve from the inner wall of the housing.

JP 2004-138062 A

  When a force in the radial direction from the inner wall of the housing acts on the member forming the valve seat of the discharge valve, the valve seat portion may be deformed. If the valve seat portion is deformed, the tight contact state (sitting state) between the valve seat and the discharge valve member is hindered, and the discharge pressure may be lowered or become unstable.

  Further, in the high pressure pump of Patent Document 1, since the member forming the valve seat of the discharge valve is simply press-fitted into the inner wall of the housing, depending on the internal pressure state during the operation of the high pressure pump, There is a risk of getting out.

  Furthermore, the high-pressure pump of Patent Document 1 includes a relief valve for returning the fuel to the pressurizing chamber of the high-pressure pump when the pressure of the fuel on the internal combustion engine side exceeds a predetermined pressure. The cylindrical member forming the valve seat of the relief valve is press-fitted into the inner wall of the high-pressure pump housing. Therefore, regarding the member forming the valve seat of the relief valve, the same problem as described above can occur.

  This invention is made | formed in view of the above-mentioned problem, The objective is to provide the high pressure pump which can suppress a deformation | transformation of the member which forms a valve seat.

  The invention described in claim 1 includes a plunger, a cylinder, a housing, a cylindrical member, a valve body, a discharge valve member, and a discharge valve biasing means. The cylinder includes a plunger receiving hole that slidably receives a reciprocable plunger, a pressurization chamber formed by an inner wall and an outer wall at one end of the plunger, a suction hole for sucking fluid into the pressurization chamber, It has a discharge hole for discharging the fluid pressurized in the pressure chamber. The housing has a first inner wall surface forming a first discharge passage communicating with the discharge hole, a second inner wall surface forming a second discharge passage communicating with the first discharge passage and having a diameter larger than the first inner wall surface; A step surface is formed between the first inner wall surface and the second inner wall surface. The cylindrical member is provided so that one end is located inside the second inner wall surface of the housing. The valve body is a cylindrical portion that is accommodated inside one end of the cylindrical member, a flange portion that extends radially outward from an end portion on the pressurizing chamber side of the cylindrical portion, and is sandwiched between one end of the cylindrical member and the step surface, A valve seat forming part that closes the end of the cylinder part opposite to the pressurizing chamber, a discharge valve seat formed on the wall surface of the valve seat forming part opposite to the cylinder part, a discharge valve seat and a valve seat forming part The discharge valve passage which connects the wall surface of the cylinder part side of this is provided. The discharge valve member can open and close the discharge valve passage by being separated from the discharge valve seat or seated on the discharge valve seat. The discharge valve urging means urges the discharge valve member in the seating direction.

  In the present invention, the valve body is provided such that the flange portion is sandwiched between the stepped surface of the housing and one end of the cylindrical member. Here, the valve body is held by the housing in a state where an axial force is applied to the flange from the stepped surface of the housing and one end of the cylindrical member. Thereby, the relative movement of the valve body in the axial direction is restricted with respect to the housing. Therefore, the discharge pressure of the high pressure pump can be stabilized.

  Moreover, in this state, it is suppressed that the force of the radial direction acts on a valve body. Therefore, the force in the radial direction is suppressed from acting on the valve seat forming portion of the valve body in which the discharge valve seat is formed, and deformation of the valve seat forming portion is suppressed. Therefore, the close contact state (sitting state) between the discharge valve seat and the discharge valve member can be maintained. As a result, the discharge pressure of the high pressure pump can be made more stable.

In the invention according to claim 2, the valve body includes a relief valve seat formed on the wall surface on the tube portion side of the valve seat forming portion, and a wall surface on the opposite side to the tube portion of the relief valve seat and the valve seat forming portion. And a relief valve passage that is not in communication with the discharge valve passage. Then, the present invention provides a relief valve member capable of opening and closing the relief valve passage by being separated from the relief valve seat or seated on the relief valve seat, and a relief valve biasing means for biasing the relief valve member in the seating direction. It has more. In this invention, it is suppressed that the force of a radial direction acts on a valve seat formation part, and the deformation | transformation of a valve seat formation part is suppressed. Therefore, a close contact state (sitting state) between the relief valve seat and the relief valve member can be maintained. As a result, the relief pressure of the high pressure pump can be stabilized.
In the invention according to claim 3, an annular gap is formed between the outer wall of the valve seat forming portion of the valve body and the inner wall of the cylindrical member. For this reason, it is possible to reliably prevent a radially inward force from acting on the portion of the valve seat forming portion where the discharge valve seat and the relief valve seat are formed from the inner wall of the cylindrical member. Therefore, deformation of the valve seat forming portion can be further suppressed.

  In the invention according to claim 4, the relief valve passage is formed so that the end portion on the opposite side to the relief valve seat is connected to the gap. Therefore, the gap can be a part of the flow path of the fluid that escapes to the pressurizing chamber side. Thereby, the passage length of the relief valve passage formed in the valve seat forming portion can be shortened. Therefore, since the volume of the space (relief valve passage) formed inside the valve seat forming portion can be reduced, the strength of the valve seat forming portion can be improved.

  In the invention described in claim 5, an internal thread groove is formed on the second inner wall surface of the housing. The cylindrical member has an outer thread groove corresponding to the inner thread groove on the outer wall at one end. And the cylindrical member is provided so that one end may be screwed inside the second inner wall surface. Thereby, the axial force can be continuously applied to the flange portion of the valve body from one end of the cylindrical member. Further, the fitting of the inner screw groove and the outer screw groove restricts the tubular member from coming out from the inside of the second inner wall surface of the housing. Therefore, for example, even if a force in the direction of coming out from the inside of the second inner wall surface acts on the valve body due to an increase in pressure on the pressure chamber side of the valve body, the valve body is Exiting from the inside is restricted.

  According to the sixth aspect of the present invention, the area where the flange portion of the valve body and the stepped surface of the housing abut is smaller than the maximum value of the cross-sectional area of the flange portion by the plane perpendicular to the axis of the cylinder portion of the valve body. Thereby, the surface pressure of the contact surface of a collar part and a level | step difference surface can be enlarged. Therefore, the space between the valve body and the housing can be kept liquid-tight. Accordingly, fluid leakage can be suppressed, and reduction in discharge pressure can be suppressed.

  According to the seventh aspect of the present invention, the area of contact between the tubular member and the flange portion of the valve body is smaller than the maximum value of the cross-sectional area of the flange portion by a plane perpendicular to the axis of the tubular portion of the valve body. Thereby, the surface pressure of the contact surface of a cylinder member and a collar part can be enlarged. For this reason, the space between the tubular member and the valve body can be kept liquid-tight. Accordingly, fluid leakage can be suppressed, and reduction in discharge pressure can be suppressed.

Sectional drawing which shows the high pressure pump by one Embodiment of this invention. II-II sectional view taken on the line of FIG. III-III sectional view taken on the line of FIG. It is sectional drawing which shows the valve body vicinity of the high pressure pump by one Embodiment of this invention, Comprising: (A) is a figure corresponding to FIG. 1, (B) is a figure corresponding to FIG.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
(One embodiment)
A high-pressure pump according to an embodiment of the present invention and a part thereof are shown in FIGS. The high-pressure pump 1 is a fuel pump that supplies fuel as a fluid at a high pressure to an engine as an internal combustion engine, for example. The fuel that the high-pressure pump 1 supplies to the engine is, for example, gasoline. That is, the fuel supply target of the high-pressure pump 1 is a gasoline engine. The high-pressure pump 1 sucks fuel from a fuel tank (not shown) and discharges it to a delivery pipe (not shown). Thereby, the fuel in the delivery pipe is accumulated and injected and supplied to the engine from the injector connected to the delivery pipe.

  The high-pressure pump 1 includes a plunger 20, a cylinder 30, a housing 40, a cylinder member 50, a valve body 60, a discharge valve member 71, a relief valve member 72, a discharge valve biasing means 80, a relief valve biasing means 90, and the like. . In the following, for the sake of convenience, the upper side of FIG. 1 will be described as “upper” and the lower side of FIG.

The plunger 20 is formed in a solid cylindrical shape from a metal such as stainless steel. The plunger 20 includes a large diameter part 21, a small diameter part 22, and a protruding part 23. The small diameter portion 22 is formed so as to extend in the axial direction from the center of one end of the large diameter portion 21, and the outer diameter is smaller than the outer diameter of the large diameter portion 21. The protruding portion 23 is formed so as to protrude from the center of the other end of the large diameter portion 21 to the side opposite to the small diameter portion 22, and the outer diameter is smaller than the outer diameter of the large diameter portion 21.
The cylinder 30 is formed in a bottomed cylindrical shape from a metal such as stainless steel. Inside the cylinder 30, the plunger 20 is inserted from the protrusion 23 side. The cylinder 30 has a pressurizing chamber 31 formed by an inner wall and an outer wall of the protruding portion 23 of the plunger 20.

  The inner wall of the cylinder 30 and the outer wall of the large diameter portion 21 of the plunger 20 are slidable. That is, the cylinder 30 accommodates the plunger 20 so as to be reciprocable and slidable in the axial direction. Here, the inside of the cylinder 30 corresponds to the “plunger receiving hole” in the claims. When the plunger 20 reciprocates inside the cylinder 30, the volume of the pressurizing chamber 31 changes. The cylinder 30 is increased in hardness by heat treatment such as quenching in order to suppress seizure and wear due to sliding of the plunger 20.

  The cylinder 30 has a suction hole 32 and a discharge hole 33 that allow communication between the radially outer side and the pressurizing chamber 31. The suction hole 32 and the discharge hole 33 are formed on a virtual straight line perpendicular to the axis of the cylinder 30. That is, the suction hole 32 is formed on the opposite side of the discharge hole 33. The cylinder 30 has an annular protrusion 34 that protrudes radially outward from the outer wall.

The housing 40 is made of a metal such as stainless steel. The housing 40 includes an upper housing 41 and a lower housing 46.
As shown in FIGS. 1-3, the upper housing 41 is formed in the substantially rectangular parallelepiped shape. The upper housing 41 has a receiving hole 42 that penetrates the center in the longitudinal direction in the lateral direction. The upper housing 41 has a suction passage 43 and a discharge passage 44 that connect the outer wall surface and the inner wall surface that forms the accommodation hole 42. The discharge passage 44 includes a first discharge passage 441 that communicates with the accommodation hole 42 and a second discharge passage 442 that communicates with the first discharge passage 441.

  The upper housing 41 includes a cylindrical first inner wall surface 451 that forms the first discharge passage 441 and a cylindrical second inner wall surface 452 that forms the second discharge passage 442 and has a diameter larger than the first inner wall surface 451. Have. An inner screw groove 453 is formed in the second inner wall surface 452. The upper housing 41 has an annular step surface 454 formed between the first inner wall surface 451 and the second inner wall surface 452. The step surface 454 corresponds to a “step surface” in the claims. Further, the upper housing 41 has a plurality of through holes 45 that connect the outer wall surface and the inner wall surface that forms the suction passage 43.

  The lower housing 46 includes a cylinder holding portion 47, a plate portion 48, and a cylindrical portion 49. The cylinder holding part 47 is formed in a hollow cylindrical shape. The plate portion 48 is formed so as to extend in a plate shape from one end of the cylinder holding portion 47 in the radially outward direction. The cylindrical portion 49 is formed so as to extend in a substantially cylindrical shape from the plate portion 48 to the side opposite to the cylinder holding portion 47. Further, a plurality of through holes 481 penetrating the plate portion 48 in the plate thickness direction are formed between the cylinder holding portion 47 and the cylinder portion 49. As shown in FIG. 2, the plate portion 48 is formed with an attachment hole 482 through which a fastening member for attaching the high-pressure pump 1 to the engine is inserted.

  The cylinder 30 is inserted and press-fitted into the inside of the cylinder holding portion 47 of the lower housing 46 and the accommodation hole 42 of the upper housing 41 from the end on the pressurizing chamber 31 side. At this time, the suction passage 43 of the upper housing 41 communicates with the suction hole 32 of the cylinder 30. The discharge passage 44 of the upper housing 41 communicates with the discharge hole 33 of the cylinder 30 on the first discharge passage 441 side.

  Further, the annular protrusion 34 of the cylinder 30 is in contact with the lower housing 46. Thereby, the cylinder 30 is restricted from moving relative to the lower housing 46 and the upper housing 41 in the axial direction. As described above, the upper housing 41 and the lower housing 46 accommodate the cylinder 30 so as not to be relatively movable.

  In the present embodiment, the cover member 11 is provided on the opposite side of the plate portion 48 of the lower housing 46 from the tube portion 49. The cover member 11 is formed in a cup shape from a metal such as stainless steel. The cover member 11 includes a substantially octagonal tubular portion 111 and a bottom portion 112 that closes one end of the tubular portion 111. The cover member 11 covers the cylinder holding portions 47 of the upper housing 41 and the lower housing 46 so as to be positioned inside the cylindrical portion 111. The end portion of the cylindrical portion 111 opposite to the bottom portion 112 is in contact with the plate portion 48 of the lower housing 46 and is welded over the entire circumference. As a result, the space between the cylinder portion 111 and the plate portion 48 is kept liquid-tight, and the fuel gallery 113 is formed inside the cover member 11.

  A hole 121 is formed at a location corresponding to the suction passage 43 of the cylindrical portion 111. Further, a hole 122 is formed at a location corresponding to the discharge passage 44 of the cylindrical portion 111. Further, as shown in FIG. 2, the fuel inlet 2 is attached to the cylindrical portion 111. The fuel inlet 2 is formed in a cylindrical shape, one end of which is fitted into a hole 123 formed in the cylindrical portion 111 and the outer periphery thereof is welded to the cylindrical portion 111. A fuel pipe connected to a fuel tank (not shown) is connected to the other end of the fuel inlet 2. Thereby, the fuel in the fuel tank is supplied to the fuel gallery 113 via the fuel pipe and the fuel inlet 2. A filter 3 is provided inside the other end of the fuel inlet 2.

  A pulsation damper 4 is provided between the bottom 112 of the fuel gallery 113 and the upper housing 41. The pulsation damper 4 is formed by joining the peripheral portions of two diaphragms, and a gas having a predetermined pressure is sealed therein. The pulsation damper 4 is held by a holding member 5 fixed near the bottom 112. The pulsation damper 4 can reduce fuel pressure pulsation by elastically deforming according to the change in fuel pressure in the fuel gallery 113.

  An oil seal holder 141 is provided at the end of the cylinder 30 opposite to the pressurizing chamber 31. The oil seal holder 141 includes a cylindrical base portion 151 through which the small diameter portion 22 of the plunger 20 is inserted, and a press-fit portion 152 that is press-fitted inside the cylindrical portion 49 of the lower housing 46. The base 151 and the press-fit portion 152 are integrally formed. An annular seal 142 is provided inside one end of the base 151. The seal 142 includes a Teflon (registered trademark) ring on the inner diameter side and a rubber ring on the outer diameter side. The seal 142 adjusts the thickness of the fuel oil film around the small-diameter portion 22 of the plunger 20 and suppresses fuel leakage to the engine. An oil seal 143 is provided at the other end of the base 151. The oil seal 143 adjusts the thickness of the oil film around the small-diameter portion 22 of the plunger 20 and suppresses oil leakage.

  The press-fit portion 152 includes an inner cylinder portion 153 that extends in a cylindrical shape from one end of the base portion 151, a connection portion 154 that extends in a radially outward direction from an end opposite to the base portion 151 of the inner tube 153, and the connection portion The outer cylindrical portion 155 extends in a cylindrical shape from the outer edge of 154 toward the base 151. As described above, the press-fit portion 152 is formed in a double cylinder shape. The press-fit portion 152 is press-fitted inside the tube portion 49 so that the outer wall of the outer tube portion 155 is in pressure contact with the inner wall of the tube portion 49 of the lower housing 46.

  A substantially disc-shaped spring seat 144 is provided at the end of the small diameter portion 22 of the plunger 20 opposite to the large diameter portion 21. A spring 145 is provided between the spring seat 144 and the connection portion 154 of the press-fit portion 152 of the oil seal holder 141.

In a state where the high-pressure pump 1 is attached to the engine, the end portion of the plunger 20 opposite to the large-diameter portion 21 of the small-diameter portion 22 contacts a tappet (not shown). The tappet makes an outer surface abut on a cam provided on a camshaft (not shown), and reciprocates in the axial direction according to the cam profile by the rotation of the camshaft. One end of the spring 145 is locked to the spring seat 144 and the other end is locked to the connection portion 154. Thereby, the spring 145 functions as a return spring of the plunger 20 and urges the plunger 20 to contact the tappet.
With the above configuration, the plunger 20 reciprocates in the axial direction according to the rotation of the camshaft, and the volume of the pressurizing chamber 31 changes accordingly.

  A suction valve portion 16 is provided in the suction passage 43 of the upper housing 41. The intake valve portion 16 includes an intake valve body 161, a first cylinder member 162, a second cylinder member 163, a needle 164, an intake valve member 165, a stopper 166, a first spring 167, a second spring 168, and the like.

  The suction valve body 161 is formed in a substantially cylindrical shape, and is provided such that an outer wall at one end abuts against an inner wall of the upper housing 41 that forms the suction passage 43. An annular suction valve seat 171 is formed on the end surface of the suction valve body 161 on the pressure chamber 31 side. The intake valve body 161 has a plurality of through holes 172 that connect the inner wall and the outer wall.

  The first cylinder member 162 is formed in a substantially cylindrical shape by, for example, a magnetic material. The first cylinder member 162 is inserted into the hole 121 of the cylinder portion 111 of the cover member 11, and is provided so that the outer wall at one end is in contact with the inner wall of the upper housing 41 that forms the suction passage 43. Note that the other end of the intake valve body 161 is positioned inside one end of the first cylindrical member 162.

  Here, the through hole 45 of the upper housing 41 and the through hole 172 of the suction valve body 161 communicate with each other. Thereby, the fuel gallery 113 and the inside of the intake valve body 161 communicate with each other via the through hole 45 and the through hole 172. Moreover, the outer wall of the 1st cylinder member 162 and the outer edge part of the hole 121 of the cover member 11 are welded over the perimeter. Thereby, the liquid tightness of the fuel gallery 113 is maintained.

The second cylinder member 163 is formed in a bottomed cylinder shape, and is provided so that the outer wall is in contact with the inner wall of the first cylinder member 162.
The needle 164 is formed in a rod shape, and is provided so as to be inserted through a hole formed in the bottom portion of the second cylindrical member 163. The needle 164 has an annular protrusion 173 that protrudes radially outward from an outer wall in the axial direction.
The suction valve member 165 is formed in a substantially disc shape and is provided on the pressure chamber 31 side of the suction valve body 161.

  The stopper 166 is formed in a bottomed cylindrical shape with a shallow bottom, and is provided on the suction chamber 31 side of the suction valve body 161 and the suction valve member 165. Here, the suction valve member 165 is provided so as to be capable of reciprocating in the axial direction between the suction valve body 161 and the stopper 166. Therefore, the suction valve member 165 can be in contact with the suction valve seat 171 of the suction valve body 161 at the outer edge portion of one surface. Further, the suction valve member 165 can abut the stopper 166 at the outer edge portion of the other surface. Note that one end of the needle 164 can contact the center of one surface of the suction valve member 165.

  The intake valve member 165 can open and close the intake passage 43 by being separated from the intake valve seat 171 of the intake valve body 161, that is, separated from the intake valve seat 171, or abutted or seated on the intake valve seat 171. Hereinafter, when the intake valve member 165 is separated from the intake valve seat 171 as appropriate, it is referred to as “opening”, and the direction in which the intake valve member 165 is separated from the intake valve seat 171 is referred to as “opening direction of the intake valve member 165. " Further, the seating of the suction valve member 165 on the suction valve seat 171 is referred to as “valve closing”, and the direction in which the suction valve member 165 is seated on the suction valve seat 171 is referred to as “the valve closing direction of the suction valve member 165”.

  The first spring 167 is provided between the bottom of the second cylindrical member 163 and the annular protrusion 173 of the needle 164, and urges the needle 164 toward the stopper 166 side. The second spring 168 is provided between the bottom of the stopper 166 and the suction valve member 165 and biases the suction valve member 165 toward the needle 164 side. In the present embodiment, the urging force of the first spring 167 is set larger than the urging force of the second spring 168. Therefore, the suction valve member 165 is biased in the valve opening direction by the first spring 167 and pressed against the stopper 166 in a state where no external force is applied to the needle 164. That is, at this time, the intake valve member 165 is opened.

On the opposite side of the suction valve section 16 from the pressurizing chamber 31, an electromagnetic drive section 18 is provided. The electromagnetic drive unit 18 includes a movable core 181, a fixed core 182 and a coil 183.
The movable core 181 is formed in a substantially cylindrical shape from a magnetic material, and is press-fitted into the end of the needle 164 opposite to the suction valve member 165. Accordingly, the movable core 181 can reciprocate in the axial direction together with the needle 164.

  The fixed core 182 is formed of a magnetic material in a solid cylindrical shape, and is provided on the opposite side of the movable core 181 from the pressurizing chamber 31. A cylinder member 185 made of a nonmagnetic material is provided between the fixed core 182 and the first cylinder member 162.

  The coil 183 is formed in a substantially cylindrical shape, and is provided on the end of the first cylindrical member 162 opposite to the pressurizing chamber 31, on the outer diameter side of the movable core 181 and the fixed core 182. The periphery of the coil 183 is covered with a mold part 184 made of a resin material. The mold part 184 has a connector part 191 formed so as to protrude radially outward from the outer wall. A terminal 192 is insert-molded in the connector portion 191. The terminal 192 and the coil 183 are electrically connected.

  The mold part 184 is covered with a first cover member 193 and a second cover member 194 except for the connector part 191. The first cover member 193 is formed in a cylindrical shape with a bottom using a magnetic material, and the bottom portion is in contact with the fixed core 182. The second cover member 194 is formed in a plate shape from a magnetic material and has a hole in the center. The end of the first cylinder member 162 opposite to the pressurizing chamber 31 is inserted through the hole. The second cover member 194 and the first cylinder member 162 are in contact with each other. Further, the second cover member 194 is in contact with the end of the first cover member 193 opposite to the bottom.

  The coil 183 generates a magnetic field when electric power is supplied from the outside via the terminal 192. When a magnetic field is generated in the coil 183, a magnetic circuit is formed in the fixed core 182, the first cover member 193, the second cover member 194, the first cylindrical member 162, and the movable core 181, and the movable core 181 together with the needle 164 is fixed core 182. Sucked to the side. At this time, the magnetic circuit is formed so as to avoid the cylindrical member 185 made of a nonmagnetic material.

When electric power is not supplied to the coil 183, the suction valve member 165 is urged toward the pressurizing chamber 31 by the urging force of the first spring 167 via the needle 164 and is in contact with the stopper 166. . At this time, since the intake valve member 165 is separated from the intake valve seat 171, the fuel flow in the intake passage 43 and the intake hole 32 is allowed. On the other hand, when the movable core 181 and the needle 164 are sucked toward the fixed core 182 by supplying power to the coil 183, the suction valve member 165 is biased by the biasing force of the second spring 168 and the like. It moves to the opposite side of the chamber 31 and contacts the suction valve seat 171. As a result, the flow of fuel in the suction passage 43 and the suction hole 32 is blocked.
As described above, the suction valve section 16 can allow or block the flow of fuel in the suction passage 43 and the suction hole 32 by the operation of the electromagnetic drive section 18. In the present embodiment, the electromagnetic drive unit 18 and the suction valve unit 16 constitute a so-called normally open type valve device.

Next, the cylinder member 50, the valve body 60, the discharge valve member 71, the relief valve member 72, the discharge valve urging means 80 and the relief valve urging means 90 will be described in detail based on FIGS. 4 (A) and (B). To do.
The cylindrical member 50 is formed in a substantially cylindrical shape with a metal such as stainless steel. The tubular member 50 is inserted into the hole 122 of the tubular portion 111 of the cover member 11 and is provided so that one end is located inside the second inner wall surface 452 of the upper housing 41. More specifically, the cylindrical member 50 has an outer thread groove 51 corresponding to the inner thread groove 453 of the second inner wall surface 452 formed on the outer wall of one end, and one end screwed into the inner side of the second inner wall surface 452. Is provided.

  The cylindrical member 50 has a step surface 52 formed between one end and the other end by making the inner diameter on one end side, that is, the pressurizing chamber 31 side larger than the inner diameter on the other end side. Moreover, the cylindrical member 50 is formed so that the inner diameter of the outermost end at one end is further larger than the other parts.

  An external thread groove 53 is formed on the outer wall of the other end of the cylindrical member 50, and a fuel pipe connected to a delivery pipe (not shown) is connected to the cylindrical member 50. Further, the outer wall of the tubular member 50 and the outer edge portion of the hole 122 of the cover member 11 are welded over the entire circumference. Thereby, the liquid tightness of the fuel gallery 113 is maintained.

  The valve body 60 is formed of, for example, a metal such as stainless steel, and includes a cylindrical portion 61, a flange portion 62, a first valve seat forming portion 63, a second valve seat forming portion 64, a step surface 65, a discharge valve seat 66, a relief valve seat. 67, a discharge valve passage 68, a relief valve passage 69, and the like.

  The cylinder part 61 is formed in a substantially cylindrical shape, and is accommodated inside one end of the cylinder member 50, that is, inside the end part on the pressurizing chamber 31 side. Here, since the cylindrical member 50 is formed so that the inner diameter of the outermost end at one end is further larger than other portions, the outer wall of the cylindrical portion 61 is only the end portion on the opposite side to the pressurizing chamber 31. A part is in contact with the inner wall of the cylindrical member 50. Thereby, an annular gap C <b> 1 is formed between the outer wall of the cylindrical portion 61 and the inner wall of the cylindrical member 50. In the present embodiment, the outer diameter of the cylindrical portion 61 is formed to be slightly larger than the inner diameter of the portion of the cylindrical member 50 that contacts the cylindrical portion 61. Therefore, the cylinder portion 61 is lightly press-fitted into the cylinder member 50.

  The flange portion 62 is formed in an annular shape so as to extend outward from the end portion of the cylindrical portion 61 on the pressurizing chamber 31 side. The flange portion 62 is sandwiched between one end of the cylindrical member 50 and the step surface 454 of the upper housing 41. Here, the cylindrical member 50 has one end at the second inner wall surface 452 so that a surface pressure of a predetermined value or more acts between the cylindrical member 50 and the flange portion 62 and between the flange portion 62 and the stepped surface 454. Screwed inside.

  As shown in FIGS. 4A and 4B, the flange portion 62 has an inner edge portion and an outer edge portion of the end face on the pressurizing chamber 31 side formed in a tapered shape. Therefore, the area where the flange portion 62 and the stepped surface 454 abut is smaller than the maximum value of the cross-sectional area of the flange portion 62 by the surface perpendicular to the axis of the cylindrical portion 61. In addition, the cylindrical member 50 also has an inner edge portion and an outer edge portion at the end on the pressurizing chamber 31 side that are tapered. Therefore, the area where the cylindrical member 50 and the flange portion 62 abut is smaller than the maximum value of the cross-sectional area of the flange portion 62 by the plane perpendicular to the axis of the cylindrical portion 61. Thereby, the surface pressure which acts between the collar part 62 and the level | step difference surface 454 and between the cylinder member 50 and the collar part 62 can be raised.

  The first valve seat forming portion 63 is formed in a solid cylindrical shape and closes the end portion of the cylinder portion 61 on the side opposite to the pressurizing chamber 31. The outer diameter of the first valve seat forming portion 63 is set smaller than the outer diameter of the cylindrical portion 61 and the inner diameter of one end side of the cylindrical member 50. Therefore, an annular gap C <b> 2 is formed between the outer wall of the first valve seat forming portion 63 and the inner wall of the cylindrical member 50. The gap C2 corresponds to a “gap” in the claims.

The second valve seat forming portion 64 is formed so as to protrude in a solid cylindrical shape from the center of the first valve seat forming portion 63 to the side opposite to the cylindrical portion 61. The outer diameter of the second valve seat forming portion 64 is smaller than the outer diameter of the first valve seat forming portion 63. Thereby, an annular step surface 65 is formed outside the second valve seat forming portion 64 in the wall surface of the first valve seat forming portion 63 on the second valve seat forming portion 64 side. In the present embodiment, the distance between the step surface 65 and the step surface 52 of the cylindrical member 50 is set to be a predetermined distance d1.
Here, the 1st valve seat formation part 63 and the 2nd valve seat formation part 64 comprise the "valve seat formation part" in a claim.

  The discharge valve seat 66 is formed on the end surface of the second valve seat forming portion 64 opposite to the first valve seat forming portion 63. The relief valve seat 67 is formed on the end surface of the first valve seat forming portion 63 on the cylindrical portion 61 side. The discharge valve seat 66 and the relief valve seat 67 are formed in an annular shape.

  The discharge valve passage 68 is formed inside the second valve seat forming portion 64 and the first valve seat forming portion 63 so as to connect the discharge valve seat 66 and the end surface of the first valve seat forming portion 63 on the cylinder portion 61 side. Has been. The relief valve passage 69 connects the relief valve seat 67 and the outer wall (outer peripheral wall) of the first valve seat forming portion 63 which is the wall surface on the opposite side of the cylindrical portion 61 of the first valve seat forming portion 63. It is formed inside the first valve seat forming part 63. That is, the relief valve passage 69 is formed so that the end opposite to the relief valve seat 67 is connected to the gap C2. The relief valve passage 69 is not in communication with the discharge valve passage 68.

  The discharge valve member 71 is formed in a substantially disc shape from a metal such as stainless steel. The discharge valve member 71 is provided so as to be able to contact the discharge valve seat 66. The relief valve member 72 is formed in a spherical shape with a metal such as stainless steel. The relief valve member 72 is provided so as to be able to contact the relief valve seat 67.

The discharge valve urging means 80 includes a holder 81 and a spring 86.
The holder 81 is formed, for example, by pressing a metal thin plate such as stainless steel, and is provided inside the cylindrical member 50. The holder 81 has a holder cylinder part 82, a holder bottom part 83, a holder collar part 84, a through hole 85, and the like.

The holder cylinder portion 82 is provided so that the second valve seat forming portion 64 is inserted at one end, that is, inside the end portion on the pressurizing chamber 31 side. The inner diameter of one end of the holder cylinder part 82 and the outer diameter of the second valve seat forming part 64 are set to be approximately the same size. Therefore, the holder tube portion 82 and the second valve seat forming portion 64 are loosely fitted. The inner diameter of one end of the holder cylinder portion 82 is set to be slightly larger than the outer diameter of the discharge valve member 71. Therefore, the discharge valve member 71 can reciprocate in the axial direction inside the holder tube portion 82.
The holder bottom portion 83 closes the other end of the holder tube portion 82.

  The holder collar 84 is formed in an annular shape so as to extend radially outward from one end of the holder cylinder 82. The holder collar portion 84 is sandwiched between the step surface 52 of the cylindrical member 50 and the step surface 65 of the first valve seat forming portion 63. Here, the holder collar portion 84 is set to have a plate thickness smaller than the distance d1 between the step surface 52 and the step surface 65, and the outer edge portion is bent toward the step surface 52 side. Therefore, the holder collar 84 can be elastically deformed between the step surface 52 and the step surface 65. As a result, a force greater than a predetermined value always acts on the holder collar 84 from the step surface 52 and the step surface 65.

A plurality of cutout grooves 841 are formed in the outer edge portion of the holder collar 84 in the circumferential direction. By the cutout groove 841, the relief valve passage 69 and the gap C <b> 2 communicate with the space on the side opposite to the pressurizing chamber 31 of the step surface 52 in the internal space of the cylindrical member 50.
A plurality of through-holes 85 are formed in the circumferential direction of the holder cylinder portion 82, and one is formed in the holder bottom portion 83. The inside and the outside of the holder 81 communicate with each other through the through hole 85.

  The spring 86 is provided between the discharge valve member 71 and the holder bottom 83. The spring 86 is a coil spring, and has one end locked to the discharge valve member 71 and the other end locked to the holder bottom 83. Thereby, the spring 86 urges the discharge valve member 71 to contact the discharge valve seat 66. That is, the spring 86 urges the discharge valve member 71 in the seating direction.

The relief valve urging means 90 includes a holder 91, a valve holding member 95 and a spring 98.
The holder 91 is formed in a bottomed cylindrical shape from a metal such as stainless steel. The holder 91 has a holder cylinder portion 92, a holder bottom portion 93, a through hole 94, and the like. The holder bottom portion 93 closes the end portion of the holder tube portion 92 on the pressurizing chamber 31 side. The holder 91 is provided such that the outer wall at the end of the holder cylinder 92 opposite to the holder bottom 93 is fitted or welded to the inner wall of the cylinder 61 of the valve body 60. A plurality of through-holes 94 are formed in the circumferential direction of the holder tube portion 92, and one is formed in the holder bottom portion 93. The inner side and the outer side of the holder 91 communicate with each other through the through hole 94.

  The valve holding member 95 includes an annular plate portion 96 and a tube portion 97 formed so as to extend from the inner edge of the plate portion 96 to the pressurizing chamber 31 side. The inner wall of the cylindrical portion 97 on the side of the plate portion 96 is formed in a tapered shape so that the diameter becomes smaller toward the pressurizing chamber 31 side. A relief valve member 72 is held inside the tapered inner wall of the cylindrical portion 97.

  The spring 98 is provided between the valve holding member 95 and the holder bottom portion 93. The spring 98 is a coil spring, and one end is locked to the valve holding member 95 and the other end is locked to the holder bottom portion 93. Accordingly, the spring 98 urges the relief valve member 72 to contact the relief valve seat 67 via the valve holding member 95. That is, the spring 98 urges the relief valve member N in the seating direction.

  As described above, the cylindrical member 50 and the valve body 60 are maintained in a joined state by light press-fitting. Further, the valve body 60 and the holder 91 are maintained in a joined state by fitting or welding. In this configuration, the cylindrical member 50, the valve body 60, the discharge valve member 71, the relief valve member 72, the discharge valve urging means 80, and the relief valve urging means 90 are assembled into a sub-assembly. be able to. Therefore, the assembly of the high-pressure pump 1 is facilitated.

Next, the operation of the high pressure pump 1 of the present embodiment will be described.
"Inhalation stroke"
When the plunger 20 moves downward in FIG. 1, the energization of the coil 183 is stopped. Therefore, the suction valve member 165 is urged toward the pressurizing chamber 31 by the needle 164 receiving a force from the first spring 167. As a result, the intake valve member 165 is separated from the intake valve seat 171 of the intake valve body 161. Further, when the plunger 20 moves downward in FIG. 1, the pressure in the pressurizing chamber 31 decreases. Therefore, the force received by the intake valve member 165 from the fuel on the intake valve seat 171 side is larger than the force received from the fuel on the pressurization chamber 31 side. As a result, a force is applied to the suction valve member 165 in a direction away from the suction valve seat 171, and the suction valve member 165 moves until it abuts against the stopper 166. When the intake valve member 165 is separated from the intake valve seat 171, that is, is opened, the fuel gallery 113 is pressurized via the through hole 45, the through hole 172, the inside of the intake valve body 161, and the intake hole 32. It communicates with the chamber 31. Accordingly, the fuel in the fuel gallery 113 is sucked into the pressurizing chamber 31 via the through hole 45 and the through hole 172 in this order.

“Weighing process”
When the plunger 20 rises from the bottom dead center toward the top dead center, the flow of fuel discharged from the pressurizing chamber 31 to the suction valve member 165 side, that is, the fuel gallery 113 side causes the suction valve member 165 to have a pressure chamber. A force is applied from the fuel on the 31st side in the direction of contacting the intake valve seat 171. However, when the coil 183 is not energized, the needle 164 is biased toward the suction valve member 165 by the biasing force of the first spring 167. Therefore, the movement of the intake valve member 165 toward the intake valve seat 171 is restricted by the needle 164. The suction valve member 165 is covered with a stopper 166 on the pressurizing chamber 31 side. Thereby, the flow of the fuel discharged from the pressurizing chamber 31 toward the fuel gallery 113 does not directly collide with the intake valve member 165. Therefore, the force in the valve closing direction applied to the intake valve member 165 by the flow of fuel is alleviated.

  In the metering stroke, the suction valve member 165 maintains a state of being separated from the suction valve seat 171 while the power supply to the coil 183 is stopped. As a result, the fuel discharged from the pressurizing chamber 31 as the plunger 20 moves up passes through the through hole 172 and the through hole 45 in this order, contrary to the case where the fuel is sucked into the pressurizing chamber 31 from the fuel gallery 113. Returned to the fuel gallery 113.

  When the coil 183 is energized during the metering process, a magnetic circuit is formed in the fixed core 182, the first cover member 193, the second cover member 194, the first cylindrical member 162, and the movable core 181 by the magnetic field generated in the coil 183. Is done. As a result, a magnetic attractive force is generated between the fixed core 182 and the movable core 181 that are separated from each other. When the magnetic attractive force generated between the fixed core 182 and the movable core 181 becomes larger than the urging force of the first spring 167, the movable core 181 moves to the fixed core 182 side. Therefore, the needle 164 integrated with the movable core 181 also moves to the fixed core 182 side. When the needle 164 moves to the fixed core 182 side, the suction valve member 165 and the needle 164 are separated from each other, and the suction valve member 165 receives no force from the needle 164. As a result, the suction valve member 165 is stopped by the biasing force of the second spring 168 and the force in the valve closing direction applied to the suction valve member 165 by the flow of fuel discharged from the pressurizing chamber 31 to the fuel gallery 113 side. It moves away from the suction valve seat 171 side. As a result, the intake valve member 165 is closed.

  When the plunger 20 moves up, the amount of fuel returned from the pressurizing chamber 31 to the fuel gallery 113 is adjusted by closing the suction passage 43, that is, between the pressurizing chamber 31 and the fuel gallery 113. As a result, the amount of fuel pressurized in the pressurizing chamber 31 is determined. The suction valve member 165 moves toward the suction valve seat 171 and the suction valve member 165 contacts the suction valve seat 171, that is, closes, whereby the flow of fuel flowing through the suction passage 43 is blocked. Thereby, the metering process of discharging the fuel from the pressurizing chamber 31 to the fuel gallery 113 is completed.

"Pressure stroke"
When the plunger 20 further rises toward the top dead center in a state where the space between the pressurizing chamber 31 and the fuel gallery 113 is closed, the fuel pressure in the pressurizing chamber 31 rises. When the pressure of the fuel in the pressurizing chamber 31 exceeds a predetermined pressure, the biasing force of the spring 86 of the discharge valve biasing means 80 and the force received by the discharge valve member 71 from the fuel downstream of the discharge valve seat 66 are resisted. The discharge valve member 71 is separated from the discharge valve seat 66. Thereby, the discharge valve member 71 is opened, and the fuel pressurized in the pressurizing chamber 31 is different from the pressurizing chamber 31 of the valve body 60 in the space inside the discharge valve passage 68 and the cylindrical member 50. It passes through the opposite side and is discharged from the high-pressure pump 1. The fuel discharged from the high-pressure pump 1 is supplied to a delivery pipe (not shown), accumulated, and supplied to the injector.

  At this time, if the pressure on the opposite side of the valve body 60 from the pressurizing chamber 31 in the space inside the cylindrical member 50 becomes a predetermined value or more, the urging force of the spring 98 of the relief valve urging means 90 and the relief valve The relief valve member 72 is separated from the relief valve seat 67 against the force received by the relief valve member 72 from the fuel upstream of the seat 67. As a result, the relief valve member 72 is opened, and the fuel on the side opposite to the pressurizing chamber 31 of the valve body 60 in the space inside the cylindrical member 50 passes to the pressurizing chamber 31 via the relief valve passage 69. Returned.

  When the plunger 20 moves to the top dead center, the power supply to the coil 183 is stopped, and the intake valve member 165 is separated from the intake valve seat 171 again. At this time, the plunger 20 again moves downward in FIG. 1, and the fuel pressure in the pressurizing chamber 31 decreases. As a result, fuel is sucked into the pressurizing chamber 31 from the fuel gallery 113.

  When the intake valve member 165 is closed and the fuel pressure in the pressurizing chamber 31 rises to a predetermined value, the energization to the coil 183 may be stopped. When the pressure of the fuel in the pressurizing chamber 31 rises, the force received by the fuel on the pressurizing chamber 31 side in the direction of contacting the suction valve seat 171 rather than the force received by the suction valve member 165 in the direction away from the suction valve seat 171 Becomes larger. Therefore, even when energization of the coil 183 is stopped, the suction valve member 165 maintains the contact state with the suction valve seat 171 by the force received from the fuel on the pressurizing chamber 31 side. Thus, the power consumption of the electromagnetic drive unit 18 can be reduced by stopping the energization of the coil 183 at a predetermined time.

By repeating the above “intake stroke”, “metering stroke”, and “pressurization stroke”, the high pressure pump 1 pressurizes and discharges the sucked fuel. The fuel discharge amount is adjusted by controlling the timing of energizing the coil 183 of the electromagnetic drive unit 18.
When the high-pressure pump 1 is operated, the “intake stroke”, “metering stroke”, and “pressurization stroke” are repeated, whereby the pressure in the pressurizing chamber 31 fluctuates periodically. Therefore, fuel pressure pulsation occurs in the fuel gallery 113 communicating with the pressurizing chamber 31. In the present embodiment, by providing the pulsation damper 4 in the fuel gallery 113, the pressure pulsation of the fuel is suppressed.

  In the “pressurization stroke”, the pressure in the pressurizing chamber 31 is increased, so that the valve body 60 receives fuel pressure from the pressurizing chamber 31 side. Further, when the pressure on the side opposite to the pressurizing chamber 31 of the valve body 60 in the space inside the cylindrical member 50 rises, the valve body 60 receives the fuel pressure from the side opposite to the pressurizing chamber 31. Thus, when the high pressure pump 1 is operated, the force due to the fuel pressure is repeatedly applied to the valve body 60 in the axial direction. However, in the present embodiment, the valve body 60 has the flange portion 62 sandwiched between the step surface 454 of the upper housing 41 and one end of the cylindrical member 50, so that relative movement in the axial direction is restricted with respect to the upper housing 41. ing.

  As described above, in this embodiment, the valve body 60 extends in the radially outward direction from the cylindrical portion 61 accommodated inside one end of the cylindrical member 50 and the end portion of the cylindrical portion 61 on the pressurizing chamber 31 side. The flange portion 62 sandwiched between one end of the tubular member 50 and the stepped surface 454 of the housing 40, the first valve seat forming portion 63 and the second valve seat for closing the end portion of the tubular portion 61 opposite to the pressurizing chamber 31. The discharge valve seat 66 formed on the wall surface on the opposite side of the tube portion 61 of the formation portion 64 and the second valve seat formation portion 64, and the wall surface of the discharge valve seat 66 and the first valve seat formation portion 63 on the tube portion 61 side A discharge valve passage 68 for connecting the two. The discharge valve member 71 can open and close the discharge valve passage 68 by being separated from the discharge valve seat 66 or seated on the discharge valve seat 66.

  With the above configuration, the valve body 60 is provided such that the flange portion 62 is sandwiched between the stepped surface 454 of the housing 40 and one end of the cylindrical member 50. Here, the valve body 60 is held by the housing 40 in a state where an axial force is applied to the flange portion 62 from the step surface 454 of the housing 40 and one end of the cylindrical member 50. As a result, the valve body 60 is restricted from moving relative to the housing 40 in the axial direction. Therefore, the discharge pressure of the high pressure pump 1 can be stabilized.

  Moreover, in this state, it is suppressed that the force of the radial direction acts on the valve body 60. Therefore, it is possible to suppress a radially inward force from acting on the first valve seat forming portion 63 and the second valve seat forming portion 64 of the valve body 60 in which the discharge valve seat 66 is formed, and the first valve seat forming portion 63. And the deformation | transformation of the 2nd valve seat formation part 64 is suppressed. Therefore, the close contact state (sitting state) between the discharge valve seat 66 and the discharge valve member 71 can be maintained. As a result, the discharge pressure of the high-pressure pump 1 can be made more stable.

In the present embodiment, the valve body 60 includes a relief valve seat 67 formed on the wall surface of the first valve seat forming portion 63 on the cylindrical portion 61 side, and the relief valve seat 67 and the first valve seat forming portion 63. A relief valve passage 69 that is connected to the wall surface on the opposite side of the cylindrical portion 63 and is not in communication with the discharge valve passage 68 is provided. In this embodiment, the relief valve member 72 can open and close the relief valve passage 69 by being separated from the relief valve seat 67 or seated on the relief valve seat 67, and the relief for biasing the relief valve member 72 in the seating direction. And a valve urging means 90. In this embodiment, it is suppressed that the force of the radial direction acts on the 1st valve seat formation part 63, and the deformation | transformation of the 1st valve seat formation part 63 is suppressed. Therefore, the close contact state (sitting state) between the relief valve seat 67 and the relief valve member 72 can be maintained. As a result, the relief pressure of the high pressure pump 1 can be stabilized.
In the present embodiment, an annular gap C <b> 2 is formed between the outer wall of the first valve seat forming portion 63 and the second valve seat forming portion 64 of the valve body 60 and the inner wall of the cylindrical member 50. Therefore, it is ensured that a radially inward force is applied from the inner wall of the cylindrical member 50 to the portion where the discharge valve seat 66 and the relief valve seat 67 of the first valve seat forming portion 63 and the second valve seat forming portion 64 are formed. Can be prevented. Therefore, deformation of the first valve seat forming portion 63 and the second valve seat forming portion 64 can be further suppressed.

  In the present embodiment, the relief valve passage 69 is formed so that the end opposite to the relief valve seat 67 is connected to the gap C2. Therefore, the gap C2 can be a part of the fuel flow path that escapes to the pressurizing chamber 31 side. Thereby, the passage length of the relief valve passage 69 formed in the 1st valve seat formation part 63 and the 2nd valve seat formation part 64 can be shortened. Therefore, since the volume of the space (relief valve passage 69) formed in the first valve seat forming portion 63 and the second valve seat forming portion 64 can be reduced, the first valve seat forming portion 63 and the second valve seat forming are reduced. The strength of the portion 64 can be improved.

  In the present embodiment, an inner thread groove 453 is formed in the second inner wall surface 452 of the housing 40. The cylindrical member 50 has an outer thread groove 51 corresponding to the inner thread groove 453 formed on the outer wall at one end. The cylindrical member 50 is provided so that one end is screwed into the second inner wall surface 452. Thereby, an axial force can be continuously applied to the flange 62 of the valve body 60 from one end of the cylindrical member 50. Further, the fitting of the inner screw groove 453 and the outer screw groove 51 restricts the tubular member 50 from coming out from the inside of the second inner wall surface 452 of the housing 40. Therefore, for example, even if a force in a direction to escape from the inside of the second inner wall surface 452 acts on the valve body 60 due to an increase in pressure on the pressurizing chamber 31 side of the valve body 60, the valve body 60 is Escaping from the inside of the second inner wall surface 452 is restricted.

  Further, in this embodiment, the area where the flange portion 62 of the valve body 60 and the stepped surface 454 of the housing 40 abut is the maximum of the cross-sectional area of the flange portion 62 by the surface perpendicular to the axis of the tubular portion 61 of the valve body 60. Less than the value. Thereby, the surface pressure of the contact surface of the collar part 62 and the level | step difference surface 454 can be enlarged. Therefore, the space between the valve body 60 and the housing 40 can be kept liquid-tight. Accordingly, fuel leakage can be suppressed, and reduction in discharge pressure can be suppressed.

  Further, in the present embodiment, the area where the tubular member 50 and the flange portion 62 of the valve body 60 abut is larger than the maximum value of the cross-sectional area of the flange portion 62 by a plane perpendicular to the axis of the tube portion 61 of the valve body 60. small. Thereby, the surface pressure of the contact surface of the cylindrical member 50 and the collar part 62 can be increased. Therefore, the space between the tubular member 50 and the valve body 60 can be kept liquid-tight. Accordingly, fuel leakage can be suppressed, and reduction in discharge pressure can be suppressed.

(Other embodiments)
In the above-described embodiment, the relief valve passage is connected to the gap between the outer wall of the valve seat forming portion (first valve seat forming portion) and the inner wall of the tubular member at the end opposite to the relief valve seat. An example is shown. On the other hand, in another embodiment of the present invention, the relief valve passage has an end portion on the opposite side to the relief valve seat that is not connected to the gap and is located on the opposite side to the pressurizing chamber of the valve seat forming portion. It is good also as forming in an end surface. Moreover, in other embodiment of this invention, the said clearance gap does not need to be formed between the outer wall of a valve seat formation part, and the inner wall of a cylinder member.

In another embodiment of the present invention, the holder of the discharge valve urging means may not have a holder collar. In this case, the structure which fixes a holder to a valve body by joining a holder cylinder part to the outer wall of a 2nd valve seat formation part by welding or caulking etc. can be considered.
In another embodiment of the present invention, the valve body may not have the second valve seat forming portion. In this case, the discharge valve seat is formed in the first valve seat forming portion.

  Further, in the above-described embodiment, an inner screw groove is formed on the second inner wall surface of the housing, and the cylindrical member is formed with an outer screw groove corresponding to the inner screw groove on the outer wall of one end, and the second end is second. The example provided by being screwed inside the inner wall surface was shown. On the other hand, in another embodiment of the present invention, the inner screw groove and the outer screw groove are not formed in the housing and the cylindrical member, and the cylindrical member is simply press-fitted inside the second inner wall surface of the housing. Also good.

  Moreover, in the above-mentioned embodiment, the example in which the inner edge part and outer edge part of the end surface at the side of the pressurization chamber of the collar part of a valve body were formed in the taper shape was shown. On the other hand, in other embodiment of this invention, the inner edge part and outer edge part of the end surface by the side of the pressure chamber of the collar part of a valve body do not need to be formed in the taper shape. That is, the area where the flange portion and the stepped surface of the housing abut may be equal to or greater than the value of the cross-sectional area of the flange portion by a surface perpendicular to the axis of the tubular portion of the valve body.

Moreover, in the above-mentioned embodiment, the example in which the inner edge part and outer edge part of the end surface at the side of the pressurization chamber of a cylinder member were formed in the taper shape was shown. On the other hand, in other embodiment of this invention, the inner edge part and outer edge part of the end surface at the side of the pressurization chamber of a cylinder member do not need to be formed in the taper shape. That is, the area where the tubular member and the flange of the valve body abut may be approximately the same as the value of the cross-sectional area of the flange due to the surface perpendicular to the axis of the tubular portion of the valve body.
In another embodiment of the present invention, the valve body may not have a relief valve seat and a relief valve passage. Moreover, it is good also as a structure which is not provided with a relief valve member and a relief valve biasing means.
Further, 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, the cover member may be formed integrally with the upper housing or the lower housing.

In another embodiment of the present invention, the electromagnetic drive unit and the suction valve unit may constitute a normally closed type (normally closed type) valve device. Further, if the intake valve portion constitutes a normally closed type valve device, the electromagnetic drive portion may not be provided.
Moreover, in other embodiment of this invention, the structure which does not install a pulsation damper inside a cover member may be sufficient. Furthermore, the structure which does not provide a cover member may be sufficient. In the case where the cover member is not provided, it is conceivable to directly supply the fuel as the fluid to the suction passage of the housing.

In another embodiment of the present invention, the high-pressure pump may be used as a fluid pump that discharges fluid toward a device other than the engine.
Thus, the present invention is not limited to the above-described embodiments, and can be applied to various forms without departing from the gist thereof.

DESCRIPTION OF SYMBOLS 1 ... High pressure pump 20 ... Plunger 30 ... Cylinder 31 ... Pressure chamber 32 ... Suction hole 33 ... Discharge hole 40 ... Housing 441 First discharge passage 442 Second discharge passage 451 First inner wall surface 452 Second inner wall surface 454 Step surface 50 Tube member 60 Valve body 61 ··· cylinder portion 62 ··· flange 63 ··· first valve seat forming portion (valve seat forming portion)
64 ··· Second valve seat forming portion (valve seat forming portion)
66 ... Discharge valve seat 68 ... Discharge valve passage 71 ... Discharge valve member 80 ... Discharge valve biasing means

Claims (7)

A reciprocating plunger; and
A plunger receiving hole for slidably receiving the plunger, a pressurizing chamber formed by an inner wall and an outer wall at one end of the plunger, a suction hole for sucking fluid into the pressurizing chamber, and an additional pressure in the pressurizing chamber. A cylinder having a discharge hole for discharging the pressurized fluid;
A first inner wall surface forming a first discharge passage communicating with the discharge hole, a second inner wall surface forming a second discharge passage communicating with the first discharge passage and having an inner diameter larger than the first inner wall surface; and A housing having a step surface formed between the first inner wall surface and the second inner wall surface;
A cylindrical member provided so that one end is located inside the second inner wall surface;
A cylindrical portion housed inside one end of the cylindrical member, a collar portion extending radially outward from an end portion of the cylindrical portion on the pressurizing chamber side and sandwiched between one end of the cylindrical member and the step surface, A valve seat forming portion for closing an end of the tube portion opposite to the pressurizing chamber, a discharge valve seat formed on a wall surface of the valve seat forming portion on the opposite side to the tube portion, the discharge valve seat and the A valve body having a discharge valve passage connecting the wall surface of the valve seat forming portion on the cylindrical portion side;
A discharge valve member capable of opening and closing the discharge valve passage by being separated from the discharge valve seat or seated on the discharge valve seat;
A discharge valve biasing means for biasing the discharge valve member in the seating direction;
A high pressure pump comprising: The valve body connects a relief valve seat formed on a wall surface of the valve seat forming portion on the tube portion side, and a wall surface on the opposite side of the relief valve seat from the tube portion of the valve seat forming portion. The discharge valve passage has a relief valve passage that is not in communication,
A relief valve member capable of opening and closing the relief valve passage by being separated from the relief valve seat or seated on the relief valve seat;
A relief valve biasing means for biasing the relief valve member in the seating direction;
The high-pressure pump according to claim 1, further comprising:   The high-pressure pump according to claim 2, wherein an annular gap is formed between an outer wall of the valve seat forming portion and an inner wall of the cylindrical member.   The high-pressure pump according to claim 3, wherein the relief valve passage is formed so that an end opposite to the relief valve seat is connected to the gap. An inner screw groove is formed on the second inner wall surface,
2. The cylindrical member according to claim 1, wherein an outer screw groove corresponding to the inner screw groove is formed on an outer wall of one end, and one end is screwed into an inner side of the second inner wall surface. The high-pressure pump as described in any one of -4.   6. The area of contact between the flange and the stepped surface is smaller than the maximum value of the cross-sectional area of the flange due to a plane perpendicular to the axis of the cylindrical portion. The high-pressure pump according to item.   The area where the said cylindrical member and the said collar part contact | abut is smaller than the maximum value of the cross-sectional area of the said collar part by the surface perpendicular | vertical to the axis | shaft of the said cylindrical part. The high-pressure pump according to item.

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