JP2012149595A - High pressure pump - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a high pressure pump for preventing the leakage of high pressure fuel, while allowing easy and accurate assembly of a discharge valve device into a discharge passage of a discharge-passage integrated pump-body.SOLUTION: In a discharge valve part 70 of the high pressure pump 1, an end face 811 of a seat part 81 previously pressed into a medium-inner-diameter passage 712 is encircled by a sloping part 73 located in a boundary area between the medium-inner-diameter passage 712 and a large-inner-diameter passage 713. The sloping part 73 is linear-taper shaped to be smaller from the side of a fuel outlet 72 toward the side of a compression chamber 12. Thus, a discharge valve member 82 to be inserted through from the side of the fuel outlet 72 toward the medium-inner-diameter passage 712 is direction-adjusted by the sloping part 73, when inserted, and so a first end face 821 of the discharge valve member 82 easily and accurately abuts to an end face 811 of the seat part 81. The discharge valve member 82 subjected to aligning action by the sloping part 73, when being inserted, is easily and accurately positioned relative to the seat part 81.

Description

  The present invention relates to a high-pressure pump used for an internal combustion engine.

Conventionally, a high-pressure pump that pressurizes and supplies fuel to a fuel supply system of an internal combustion engine is known. The fuel pumped up from the fuel tank is sucked into the pressurizing chamber by the lowering of the plunger in the cylinder hole of the high pressure pump, and is metered and pressurized by the raising of the plunger.
The fuel pressurized in the pressurizing chamber of the high-pressure pump is discharged to the fuel outlet through the discharge passage. A discharge valve device for preventing the high-pressure fuel discharged from the pressurizing chamber from flowing back into the pressurizing chamber is assembled in the discharge passage.
Also in the high-pressure pump described in Patent Document 1, a discharge valve device that functions as a check valve that prevents backflow of high-pressure fuel to the pressurizing chamber is assembled in a discharge passage through which high-pressure fuel is discharged from the pressurizing chamber. (See FIGS. 1 and 2 of Patent Document 1).

US 7401593B2 Specification

  By the way, the discharge valve device (check valve 44 in Patent Document 1) used in the high-pressure pump described in Patent Document 1 has all the components, such as a seat portion, a discharge valve member, a spring, and a support member, sub-assembled. . The discharge passage on the fuel outlet side from the sub-assembly discharge valve device assembled to this high-pressure pump is formed in a separate body (high-pressure connection 63) from the pump body having a cylinder hole and a pressure chamber. Yes. That is, it is difficult to assemble a conventional sub-assembly discharge valve device into a so-called discharge passage integrated pump body in which a discharge passage is formed in the same body together with a cylinder hole and a pressurizing chamber. Accordingly, there is a problem in that a connection portion is provided between the pump body in which the discharge valve device is assembled and a separate body in which the discharge passage on the fuel outlet side is formed, and high-pressure fuel may leak from this connection portion. was there.

As a method for solving the problem of high-pressure fuel leakage, it is conceivable to employ a discharge passage integrated pump body, insert individual components of the discharge valve device into the discharge passage, and assemble the discharge valve device.
However, when a discharge valve device in which the discharge passage is sub-assembled into a separate pump body is assembled as in the prior art, it is easy to position the discharge valve device in which the valve member is incorporated. When assembling the discharge valve device by inserting individual components into the discharge passage of the passage-integrated pump body, there is a problem that it is not easy to position the valve member.

  The present invention has been made in view of the above problems, and provides a high-pressure pump that can be miniaturized and that can easily and accurately assemble a discharge valve device in a discharge passage of a discharge passage-integrated pump body to prevent leakage of high-pressure fuel. The purpose is to do.

According to the first aspect of the invention, the cylinder forming member communicates with the cylindrical cylinder hole that accommodates the plunger so as to be reciprocally movable in the axial direction, and the fuel sucked by the reciprocating movement of the plunger is pressurized. And a first discharge passage communicating with the pressurizing chamber and discharging high-pressure fuel pressurized in the pressurizing chamber. The pump body has a second discharge passage that communicates with the first discharge passage and discharges the high-pressure fuel toward the fuel outlet of the pressurizing chamber. The cylindrical sheet portion is formed at a predetermined position of the discharge passage composed of the first discharge passage and the second discharge passage, and its end face faces the fuel outlet side. An inclined portion is formed at a position on the inner wall portion of the discharge passage and surrounding the end surface of the sheet portion. The inclined portion has an inner diameter that decreases from the discharge passage on the fuel outlet side toward the discharge passage on the pressurizing chamber side. The discharge valve member is inserted into the second discharge passage from the fuel outlet side. The discharge valve member has a valve portion sandwiched between a first end surface and a second end surface, and the first end surface abuts on the end surface of the seat portion. The urging member is inserted into the second discharge passage from the fuel outlet side, and one end thereof abuts on the second end surface of the discharge valve member. The cylindrical support member is inserted into the second discharge passage from the fuel outlet side, and abuts on the other end of the urging member.
Thus, in the high pressure pump according to the first aspect, the inclined portion formed in the inner wall portion of the discharge passage is in a position surrounding the end surface of the seat portion, and the inner diameter thereof is from the fuel outlet side toward the pressurizing chamber side. It is getting smaller. Thus, when the discharge valve member is inserted from the fuel outlet side, the direction of the discharge valve member being inserted is adjusted by the inclined portion, and the first end surface of the discharge valve member is easily and accurately applied to the end surface of the seat portion. Touch. That is, in the process in which the discharge valve member is inserted into the discharge passage from the fuel outlet side, the alignment operation is performed by the inclined portion, and the discharge valve member is easily and accurately positioned with respect to the seat portion.

According to the second aspect of the invention, the second discharge passage has the small inner diameter passage, the medium inner diameter passage, and the large inner diameter passage that increase in inner diameter in order from the pressurizing chamber side to the fuel outlet side. The seat portion is inserted into the inner diameter passage from the fuel outlet side. The inclined portion is formed at the boundary between the medium inner diameter passage and the large inner diameter passage. The discharge valve member is inserted into the large inner diameter passage from the fuel outlet side. And the 1st end surface of this discharge valve member contact | abuts to the end surface of a sheet | seat part in the position surrounded by the inclination part.
Thus, in the high-pressure pump according to claim 2, even when the seat portion is disposed in the inner diameter passage of the second discharge passage, the discharge valve member extends from the fuel outlet side to the large inner diameter passage of the second discharge passage. When the first end surface of the discharge valve member comes into contact with the end surface of the seat portion at a position surrounded by the inclined portion, by the alignment action of the inclined portion at the boundary between the medium inner diameter passage and the large inner diameter passage, Easy and accurate positioning of the discharge valve member with respect to the seat portion is performed.

According to the invention which concerns on Claim 3, the sheet | seat part is formed in the outer wall part of a cylinder formation member. The inclined portion is formed at the boundary between the first discharge passage and the second discharge passage. The discharge valve member is inserted into the second discharge passage from the fuel outlet side. And the 1st end surface of this discharge valve member contact | abuts to the end surface of a sheet | seat part in the position surrounded by the inclination part.
Thus, in the high pressure pump according to the third aspect, when the seat portion is formed on the outer wall portion of the cylinder forming member, the discharge valve member is inserted from the fuel outlet side toward the first discharge passage, When the one end surface comes into contact with the end surface of the sheet portion at a position surrounded by the inclined portion, the centering action of the inclined portion at the boundary between the first discharge passage and the second discharge passage causes the discharge valve member to Easy and accurate positioning is achieved.

According to the invention which concerns on Claim 4, the inclination part has comprised the taper shape. Here, “the inclined portion has a tapered shape” means that “the inner wall section of the inclined portion cut along the central axis of the discharge passage has a tapered shape”.
Thus, in the high pressure pump according to claim 4, since the inclined portion has a tapered shape, the alignment action by the inclined portion with respect to the discharge valve member being inserted is effectively exhibited. Easy and accurate positioning with respect to the seat portion is performed.

According to the invention which concerns on Claim 5, the inclined part has comprised the staircase shape. Here, “the inclined portion has a staircase shape” means that “the inner wall cross section of the inclined portion cut along the central axis of the discharge passage has a staircase shape”.
Thus, in the high pressure pump according to claim 5, since the inclined portion has a stepped shape, the alignment action by the inclined portion with respect to the discharge valve member being inserted is effectively exhibited. Easy and accurate positioning with respect to the seat portion is performed.

According to the invention of claim 6, the support member is press-fitted into the second discharge passage.
Thus, in the high pressure pump according to the seventh aspect, the support member is stably fixed by press-fitting the support member into the second discharge passage, and the other end is locked by the support member. The first end surface of the discharge valve member is appropriately biased to the end surface of the seat portion by the biasing force of the member. For this reason, the proper function as a discharge valve apparatus is ensured.

According to the invention which concerns on Claim 7, a discharge valve member has a guide part extended | stretched from a valve part to the 2nd end surface side. The support member has an inner diameter portion that guides a guide portion when the discharge valve member reciprocates. The support member has a communication hole opened in the wall surface. The communication hole is for allowing high-pressure fuel flowing from the pressurizing chamber toward the fuel outlet when the first end surface of the discharge valve member is separated from the end surface of the seat portion.
Thus, in the high pressure pump according to claim 7, the support member guides the guide portion of the discharge valve member, so that the reciprocating movement of the discharge valve member becomes stable and smooth, and an appropriate function as the discharge valve device is ensured. Is done. Further, since the support member has a communication hole in the wall surface, when the first end surface of the discharge valve member is separated from the end surface of the seat portion, the flow of high-pressure fuel from the pressurizing chamber toward the fuel outlet becomes smooth, The proper functioning of the high-pressure pump is ensured.

According to the invention which concerns on Claim 8, a support member has an edge part used as the stopper which controls the maximum lift amount when a discharge valve member reciprocates.
Thus, in the high-pressure pump according to claim 8, the support member has an end portion serving as a stopper that regulates the maximum lift amount of the discharge valve member, so that the reciprocating movement of the discharge valve member becomes safe and appropriate, An appropriate function as a discharge valve device is ensured.

According to the invention which concerns on Claim 9, a discharge valve member has a guide part extended | stretched from a valve part to the 2nd end surface side. The support member has an inner diameter portion that guides a guide portion when the discharge valve member reciprocates, and an end portion that serves as a stopper that regulates the maximum lift amount of the discharge valve member. The support member has a communication hole opened in the wall surface.
Then, an inner-diameter cross-sectional area of the seat portion (upstream passage area) and A _IN, the area (maximum opening formed between the seat portion when the discharge valve member is maximum lift and the valve portion of the discharge valve member Assuming that the opening area is A _S and the area of the communication hole (downstream passage area) is A _OUT , the following formula: A _OUT <A _S <1.5 × A _IN
The support member regulates the maximum lift amount of the discharge valve member so that is established.
High-pressure pump in this way according to claim 9, between the downstream passage area A _OUT and the maximum opening area A _S, the following equation A _OUT <A _S
Since the downstream passage area A _OUT is relatively small, the fuel pressure on the fuel outlet side (downstream side) is relatively increased from the valve portion of the discharge valve member, and the first of the discharge valve member When the end surface is about to be seated on the end surface of the seat portion, pressure is easily applied to the valve portion of the discharge valve member from the downstream side, so that the valve closing speed is increased.
Further, between the maximum opening area A _S and the upstream passage area A _IN , the following expression A _S <1.5 × A _IN
Since the maximum opening area _AS is relatively small, the maximum lift amount of the discharge valve member is restricted so that the lift of the discharge valve member more than necessary is suppressed. For this reason, the moving distance of the discharge valve member is shortened, and the valve closing speed is increased.
Therefore, the discharge efficiency of the high-pressure pump is increased and the performance is improved.

According to the invention of claim 10, the cylinder forming member and the pump body are continuously integrated.
That is, even when a so-called cylinder-integrated pump body in which the cylinder forming member and the pump body are continuously integrated is used, the cylinder forming member is different from the pump body in the case of a so-called separate cylinder. However, the invention of the high-pressure pump according to claims 1 to 9 is applied.

It is sectional drawing which shows the high pressure pump by 1st Embodiment of this invention. FIG. 2 is an enlarged cross-sectional view of a discharge valve portion surrounded by a two-dot chain line of the high-pressure pump in FIG. 1, and is a cross-sectional view showing a discharge valve device (valve closed state) assembled to the discharge valve portion. It is sectional drawing which shows the valve opening state of the discharge valve apparatus of FIG. It is sectional drawing which shows the discharge valve apparatus (valve closed state) assembled | attached to the discharge valve part of the high pressure pump by 2nd Embodiment of this invention. It is sectional drawing which shows the valve opening state of the discharge valve apparatus of FIG. It is sectional drawing which shows the discharge valve apparatus (valve closed state) assembled | attached to the discharge valve part of the high pressure pump by 3rd Embodiment of this invention. It is sectional drawing which shows the discharge valve apparatus (valve closed state) assembled | attached to the discharge valve part of the high pressure pump by 4th Embodiment of this invention.

Hereinafter, a plurality of embodiments of the present invention will be described with reference to the drawings.
(First embodiment)
1 and 2 show a state in which the discharge valve device is assembled to the discharge valve portion of the high-pressure pump according to the first embodiment of the present invention (closed state), and shows the valve open state at the time of maximum lift of the discharge valve device. As shown in FIG.
First, the high-pressure pump 1 according to the present embodiment will be described with reference to FIG.
The high-pressure pump 1 is provided in a fuel supply system that supplies fuel to the internal combustion engine. The fuel pumped up from the fuel tank is pressurized by the high-pressure pump 1 and accumulated in the delivery pipe. The fuel is injected and supplied to each cylinder of the internal combustion engine from an injector connected to the delivery pipe.
The high-pressure pump 1 includes a pump body 10, a plunger unit 20, a damper chamber 40, a suction valve unit 50, an electromagnetic drive unit 60, a discharge valve unit 70, and the like.

(A) The pump body 10 and the plunger part 20 are demonstrated.
The pump body 10 is integrally formed with a cylindrical cylinder hole 11 and a pressurizing chamber 12 communicating with the cylinder hole 11. In the present embodiment, the pump body 10 corresponds to a “cylinder forming member” and a “pump body” recited in the claims.
The plunger portion 20 includes a plunger 21, a plunger stopper 23, a seal member 24, an oil seal holder 25, a plunger spring 28, and the like.

  The plunger 21 is accommodated in the cylinder hole 11 and is held so as to be capable of reciprocating in the central axis direction. The plunger 21 has a large-diameter portion 211 that slides with the inner wall that forms the cylinder hole 11, and a small-diameter portion 212 that has a smaller outer diameter than the large-diameter portion 211. The end of the plunger 21 on the large diameter portion 211 side faces the pressurizing chamber 12, and the spring seat 27 is provided on the end of the small diameter portion 212 side.

A substantially annular plunger stopper 23 is provided around the small diameter portion 212 of the plunger 21. A part of the plunger stopper 23 is connected to and fixed to the pump body 10, and an end surface facing the pressurizing chamber 12 side is relative to the step surface 213 between the large diameter portion 211 and the small diameter portion 212 of the plunger 21. is doing.
A seal member 24 is mounted around the small-diameter portion 212 around the small-diameter portion 212 on the spring seat 27 side of the plunger stopper 23. The inner diameter side Teflon ring (“Teflon” is a registered trademark) and the outer diameter side O-ring in contact with the small diameter portion 212 and the outer diameter side O-ring are regulated, and the thickness of the fuel oil film around the small diameter portion 212 is regulated, and the plunger 21 slides. This suppresses fuel leakage to the engine.

An oil seal holder 25 is provided around the small-diameter portion 212 on the spring seat 27 side with respect to the seal member 24. A part of the oil seal holder 25 is fitted and fixed in a substantially annular recess formed in the pump body 10. Thus, the seal member 24 is sandwiched and fixed between the oil seal holder 25 and the plunger stopper 23.
An oil seal 26 is attached to the end of the oil seal holder 25 on the spring seat 27 side so as to surround the small diameter portion 212. The oil seal 26 regulates the thickness of the oil film around the small-diameter portion 212 and suppresses oil leakage due to the sliding of the plunger 21.

A spring seat 27 is coupled to the end of the plunger 21. One end of a plunger spring 28 is locked to the spring seat 27. The other end of the plunger spring 28 is engaged with an oil seal holder 25 fixed to the pump body 10. That is, the plunger spring 28 functions as a return spring for the plunger 21 and urges the plunger 21 to contact the tappet.
Due to the function of the plunger spring 28, the plunger 21 reciprocates in the axial direction of the cylinder hole 11 by contacting the cam of the camshaft via a tappet (not shown). Then, the reciprocating movement of the plunger 21 changes the volume of the pressurizing chamber 12 so that the fuel is sucked and pressurized.

  The variable volume chamber 30 is formed by the stepped surface 213 of the plunger 21, the outer wall of the small diameter portion 212, the inner wall constituting the cylinder hole 11 of the pump body 10, the plunger stopper 23 and the seal member 24. Has been. Further, between the oil seal holder 25 and the pump body 10, a cylindrical passage 31 and an annular passage 32 that are in communication with each other are formed. In addition, a return passage 33 communicating with the annular passage 32 is formed in the pump body 10. The variable volume chamber 30 communicates with the damper chamber 40 via the cylindrical passage 31, the annular passage 32, and the return passage 33.

(B) The damper chamber 40 will be described.
The damper chamber 40 includes a recess 41, a cover 42, a damper unit 43, and the like.
The pump body 10 is provided with a recess 41 that is recessed toward the cylinder hole 11 on the opposite side of the cylinder hole 11. The concave portion 41 is covered with a bottomed cylindrical cover 42 for blocking the inside from outside air.

A damper unit 43 is disposed in the damper chamber 40. The damper unit 43 includes a pulsation damper 44 formed by joining two metal diaphragms 441 and 442, a bottom support 45 disposed on the bottom of the recess 41, and a lid support supported on the cover 42 side. Part 46.
In the pulsation damper 44, a gas having a predetermined pressure is sealed inside two metal diaphragms 441 and 442. The two metal diaphragms 441 and 442 are elastically deformed according to the pressure change in the damper chamber 40, thereby reducing the fuel pressure pulsation in the damper chamber 40.

A recess 47 is formed at the bottom of the recess 41 of the damper chamber 40 so as to match the bottom support 45. The bottom support portion 45 is positioned by the recess 47. In addition, although not shown, an inlet opening is formed in the recess 47, so that fuel from the low-pressure pump is supplied to the radially inner region of the bottom support 45. That is, the fuel in the fuel tank is supplied to the damper chamber 40 from the fuel inlet through the fuel passage.
A wave spring 48 is disposed above the lid side support 46. Thereby, the wave spring 48 presses the lid side support part 46 toward the bottom side instruction part 45 in a state where the cover 42 is attached to the pump body 10. As a result, the pulsation damper 44 is clamped and fixed at the periphery by the lid-side support portion 46 and the bottom-side support portion 45 with an equal force in the circumferential direction.

(C) The suction valve unit 50 will be described.
The suction valve unit 50 includes a supply passage 52, a valve body 53, a seat portion 54, a suction valve 55, and the like.
The pump body 10 is provided with a cylindrical portion 51 substantially perpendicular to the central axis of the cylinder hole 11, and the inside of the cylindrical portion 51 is a fuel supply passage 52. Further, a valve body 53 is accommodated inside the cylindrical portion 51 and is fixed by a locking member. A seat portion 54 having a concave tapered circumferential surface is formed inside the valve body 53, and a suction valve 55 is disposed opposite to the seat portion 54. The suction valve 55 is guided by an inner wall of a hole provided at the bottom of the valve body 53 and reciprocates. The suction valve 55 is separated from the seat portion 54 to open the supply passage 52. When the suction valve 55 is seated on the seat portion 54, the supply passage 52 is closed.

A stopper 56 is fixed to the inner wall of the valve body 53, and this stopper 56 restricts the movement of the intake valve 55 in the valve opening direction (right direction in FIG. 1). A first spring 57 is provided between the inside of the stopper 56 and the end face of the suction valve 55. The first spring 57 attaches the suction valve 55 in the valve closing direction (left direction in FIG. 1). Rush.
The stopper 56 is formed with a plurality of inclined passages 58 that are inclined with respect to the axis of the stopper 56 in the circumferential direction. The fuel supplied through the supply passage 52 is sucked into the pressurizing chamber 12 through the inclined passage 58. The supply passage 52 communicates with the damper chamber 40 via the pressurization side passage 59.

(D) The electromagnetic drive unit 60 will be described.
The electromagnetic drive unit 60 includes a connector 61, a fixed core 62, a movable core 63, a flange 64, and the like.
The connector 61 includes a coil 611 and a terminal 612, and generates a magnetic field when the coil 611 is energized through the terminal 612. The fixed core 62 is made of a magnetic material and is accommodated inside the coil 611. The movable core 63 is made of a magnetic material and is disposed to face the fixed core 62. The movable core 63 is accommodated inside the flange 64 so as to be capable of reciprocating in the axial direction.

The flange 64 is made of a magnetic material and is attached to the cylinder portion 51 of the pump body 10. The flange 64 holds the connector 61 and the like on the pump body 10 and closes the end portion of the cylindrical portion 51. A cylindrical guide cylinder 65 is attached to the inner wall of the hole provided in the center of the flange 64. The cylindrical member 66 made of a nonmagnetic material prevents a magnetic short circuit between the fixed core 62 and the flange 64.
The needle 67 is formed in a substantially cylindrical shape and reciprocates while being guided by the inner wall of the guide cylinder 65. Further, one end of the needle 67 is fixed to the movable core 63, and the other end can be brought into contact with the end surface of the suction valve 55 on the electromagnetic drive unit 60 side.

A second spring 68 is provided between the fixed core 62 and the movable core 63. The second spring 68 biases the movable core 63 in the valve closing direction with a force stronger than the force that the first spring 57 biases the suction valve 55 in the valve closing direction.
When the coil 611 is not energized, the movable core 63 and the fixed core 62 are separated from each other by the elastic force of the second spring 68. As a result, the needle 67 integral with the movable core 63 moves to the suction valve 55 side, and the suction valve 55 is opened when the end surface of the needle 67 presses the suction valve 55.

(E) The discharge valve unit 70 will be described.
The discharge valve unit 70 includes a discharge passage 71, a discharge valve device 80, and the like.
A discharge passage 71 is formed in the pump body 10 substantially perpendicularly to the central axis of the cylinder hole 11. The discharge passage 71 communicates with the pressurizing chamber 12 on the one hand and communicates with the fuel outlet 72 on the other hand. In addition, the discharge passage 71 has an inner diameter passage 711, an inner diameter passage 712, a larger inner diameter passage 713, and an outer diameter passage 713 that are relatively smaller in inner diameter than the pressurizing chamber 12 side toward the fuel outlet 72 side. The first passage 714 has an outlet-side second passage 715 having a relatively larger inner diameter than the outlet-side first passage 714. In addition, an inclined portion 73 having a linear taper shape is formed on the inner wall portion at the boundary between the medium inner diameter passage 712 and the large inner diameter passage 713.
In the present embodiment, the small inner diameter passage 711 corresponds to a “first discharge passage” and a “second discharge passage” recited in the claims. The medium inner diameter passage 712, the large inner diameter passage 713, the outlet side first passage 714, and the outlet side second passage 715 correspond to a “second discharge passage”.

Next, a state in which the discharge valve device 80 is assembled to the discharge valve portion 70 of the high-pressure pump 1 will be described with reference to FIG.
The discharge valve device 80 includes a seat portion 81, a discharge valve member 82, a spring 83, an adjusting pipe 84, and the like.
A cylindrical sheet portion 81 is press-fitted into the inner diameter passage 712 of the discharge passage 71. In the seat portion 81, the end surface on the one pressurizing chamber 12 side abuts on the step surface between the small inner diameter passage 711 and the inner inner diameter passage 712, and the end surface 811 having a cylindrical cross section on the other fuel outlet 72 side is inclined around the periphery. Surrounded by part 73.

  A discharge valve member 82 is accommodated in the large inner diameter passage 713 of the discharge passage 71 relative to the seat portion 81. The discharge valve member 82 is sandwiched between a first end surface 821 that contacts the end surface 811 of the seat portion 81, a second end surface 822 opposite to the first end surface 821, and the first end surface 821 and the second end surface 822. It has a valve portion 823 and a guide portion 824 extending from the valve portion 823 to the second end face 821 side.

A spring 83 as an urging member is accommodated in the large inner diameter passage 713 of the discharge passage 71. One end of the spring 83 is in contact with the second end surface 822 of the discharge valve member 82.
A cylindrical adjusting pipe 84 is press-fitted into the large inner diameter passage 713 and the outlet side first passage 714 of the discharge passage 71. The adjusting pipe 84 includes a small outer diameter portion 841 having a relatively small outer diameter on the pressurizing chamber 12 side, and a large outer diameter portion 842 having a relatively large outer diameter on the fuel outlet 72 side. . The outer peripheral surface of the large outer diameter portion 842 is fixed in close contact with the inner peripheral surface of the outlet-side first passage 714 by press-fitting. A space 74 is formed between the outer peripheral surface of the small outer diameter portion 841 and the inner peripheral surface of the large inner diameter passage 713 having an inner diameter larger than that of the outlet-side first passage 714.

The adjusting pipe 84 locks the end of the spring 83 as a support member. Therefore, the first end surface 821 of the valve portion 823 of the discharge valve member 82 is urged against the end surface 811 of the seat portion 81 by the urging force of the spring 83 whose end is locked to the adjusting pipe 84. become.
The adjusting pipe 84 has an inner peripheral surface 843 that guides the guide portion 824 when the discharge valve member 82 reciprocates in the center line direction of the discharge passage 71, and a maximum lift amount when the discharge valve member 82 reciprocates. A stopper end portion 844 serving as a stopper for regulating α and a communication hole 845 opened in the small outer diameter portion 841 are provided.

Here, the communication hole 845 includes a space 74 formed between the outer peripheral surface of the small outer diameter portion 841 and the inner peripheral surface of the large inner diameter passage 713, the inner peripheral surface 843 of the adjusting pipe 84, and the discharge valve member 82. The space sandwiched between the end surface of the guide portion 824 on the fuel outlet 72 side is communicated.
Further, as shown in FIG. 3, the stopper end portion 844 includes an inner diameter sectional area (upstream passage area) _AIN of the seat portion 81, and the seat portion 81 and the discharge valve member 82 when the discharge valve member 82 is fully lifted. Between the area (maximum opening area) A _{S of the} opening formed between the valve section 823 and the area (downstream passage area) A _OUT of the communication hole 845, the following expression A _OUT <A _S < 1.5 x A _IN
The maximum lift amount α of the discharge valve member 82 is regulated so that is established.

Next, a method for assembling the discharge valve device 80 to the discharge valve portion 70 of the high-pressure pump 1 will be described.
First, the seat portion 81 is press-fitted into the medium inner diameter passage 712 of the discharge passage 71 from the fuel outlet 72 side, and its outer peripheral surface is brought into close contact with the inner peripheral surface of the medium inner diameter passage 712 and fixed. At this time, the end surface on the pressurizing chamber 12 side of the seat portion 81 is in contact with the step surface between the small inner diameter passage 711 and the inner inner diameter passage 712, and the end surface 811 on the fuel outlet 72 side is surrounded by the inclined portion 73. To be in a position where

Subsequently, the discharge valve member 82 is inserted into the large inner diameter passage 713 from the fuel outlet 72 side with the first end face 821 facing the pressurizing chamber 12 side. Then, the first end surface 821 of the discharge valve member 82 is brought into contact with the end surface 811 of the seat portion 81.
At this time, the end surface 811 of the seat portion 81 is at a position surrounded by the inclined portion 73 at the boundary between the medium inner diameter passage 712 and the large inner diameter passage 713, and the inner diameter of the inclined portion 73 is the large inner diameter passage on the fuel outlet 72 side. The discharge valve member 82 inserted from the fuel outlet 72 side toward the medium inner diameter passage 712 has an inclined portion due to the linear taper shape that decreases from the fuel outlet 713 toward the medium inner diameter passage 712 from the pressure chamber 12 side. The orientation of the insertion is adjusted by 73, and the first end surface 821 of the discharge valve member 82 is brought into contact with the end surface 811 of the seat portion 81 easily and accurately. That is, since the discharge valve member 82 is subjected to the alignment operation by the inclined portion 73 having a linear taper shape in the process of being inserted from the fuel outlet 72 side toward the medium inner diameter passage 712, the seat portion 81 of the discharge valve member 82 is provided. Easy and accurate positioning with respect to

Subsequently, the spring 83 is inserted into the large inner diameter passage 713 from the fuel outlet 72 side. Then, one end of the spring 83 is brought into contact with the second end surface 822 of the discharge valve member 82.
Subsequently, the adjusting pipe 84 is inserted from the fuel outlet 72 side into the outlet-side first passage 714 and the large-inner-diameter passage 713 with the small outer-diameter portion 841 facing the pressurizing chamber 12 side, and the larger outer-diameter portion 842 is press-fitted into the outlet-side first passage 714, and the outer peripheral surface of the large outer diameter portion 842 is brought into close contact with the inner peripheral surface of the outlet-side first passage 714 and fixed.
At this time, the adjusting pipe 84 is locked to the other end of the spring 83. Further, the guide portion 824 of the discharge valve member 82 is inserted into the inner diameter portion 8 of the adjusting pipe 84.

  Thus, the seat 81, the discharge valve member 82, the spring 83, and the adjusting pipe 84 are inserted into the discharge passage 71 in order from the fuel outlet 72 side and housed, whereby the spring whose end is locked to the adjusting pipe 84. The discharge valve device 80 in which the first end surface 821 of the valve portion 823 of the discharge valve member 82 is urged by the end surface 811 of the seat portion 81 by the urging force 83 is assembled to the discharge valve portion 70.

Next, the operation of the discharge valve unit 70 to which the discharge valve device 80 is assembled will be described with reference to FIGS.
As the plunger 21 rises in the cylinder hole 11, the fuel pressure in the pressurizing chamber 12 rises. The force received by the valve member 83 from the fuel on the pressure chamber 12 side (upstream side) of the valve member 83 of the valve member device 80 is the elastic force of the spring 84 and the fuel outlet 72 side (downstream side) of the valve member 83. As shown in FIG. 3, the first end surface 821 of the valve member 83 is separated from the end surface 731 of the seat portion 73. That is, the discharge valve device 80 is opened. Thereby, the high-pressure fuel pressurized in the pressurizing chamber 12 is discharged from the small inner diameter passage 711 and the medium inner diameter passage 712 to the fuel outlet 72 through the large inner diameter passage 713.

  On the other hand, as the plunger 21 descends in the cylinder hole 11, the fuel pressure in the pressurizing chamber 12 decreases. When the force received by the valve member 83 from the fuel on the upstream side becomes smaller than the sum of the elastic force of the spring 84 and the force received from the fuel on the downstream side, as shown in FIG. The first end surface 821 is seated on the end surface 811 of the seat portion 81. That is, the discharge valve device 80 is closed. This prevents fuel downstream from the discharge valve member 82 from flowing back into the upstream pressurizing chamber 12.

At this time, the maximum lift amount α of the discharge valve member 82 is set between the upstream passage area A _IN , the maximum opening area _AS and the downstream passage area A _OUT by the stopper end 844 of the adjusting pipe 84. Formula A _OUT <A _S <1.5 × A _IN
Is regulated to hold.

That is, between the downstream passage area A _OUT and the maximum opening area A _S , the following expression A _OUT <A _S
Since the downstream passage area A _OUT becomes relatively small, the pressure of the fuel on the downstream side of the valve portion 823 of the discharge valve member 82 relatively increases. For this reason, when the first end surface 821 of the discharge valve member 82 is about to be seated on the end surface 811 of the seat portion 81, pressure is easily applied to the valve portion 823 of the discharge valve member 82 from the downstream side. Thus, the valve closing speed of the discharge valve device 80 is increased.

Further, between the maximum opening area A _S and the upstream passage area A _IN , the following expression A _S <1.5 × A _IN
Since the maximum opening area _AS is relatively small, the maximum lift amount α of the discharge valve member 82 is regulated to be small. For this reason, it is suppressed that the discharge valve member 82 lifts more than necessary, and the moving distance of the discharge valve member 82 becomes short. Thus, the valve closing speed of the discharge valve device 80 increases.
Thus, the valve member device 80 assembled to the discharge valve portion 70 of the high pressure pump 1 functions as a check valve for the high pressure fuel discharged from the pressurizing chamber 12 toward the fuel outlet 72.

Next, the operation of the high-pressure pump 1 will be described.
(1) Suction stroke When the plunger 21 descends from the top dead center toward the bottom dead center in the cylinder hole 11 due to the rotation of the camshaft, the volume of the pressurizing chamber 12 increases and the fuel in the pressurizing chamber 12 flows. Depressurized. At this time, in the discharge valve portion 70, the discharge valve member 82 of the discharge valve device 80 is seated on the seat portion 81 and closes the discharge passage 71. Further, in the suction valve section 50, the suction valve 55 moves to the right in FIG. 1 against the urging force of the first spring 57 due to the pressure difference between the pressurizing chamber 12 and the supply passage 52, and the valve is opened. It becomes a state. At this time, since the energization of the coil 611 of the electromagnetic drive unit 60 is stopped, the movable core 63 and the needle 67 integral with the movable core 63 move to the right in FIG. 1 by the urging force of the second spring 68. . Accordingly, the needle 67 and the suction valve 55 come into contact with each other, and the suction valve 55 maintains the open state. As a result, fuel is sucked into the pressurizing chamber 12 from the supply passage 52.

In the suction stroke, the volume of the variable volume chamber 30 decreases due to the lowering of the plunger 21. Accordingly, the fuel in the variable volume chamber 30 is sent out to the damper chamber 40 via the cylindrical passage 31, the annular passage 32, and the return passage 33.
Here, the cross-sectional area ratio between the large diameter portion 211 and the variable volume chamber 30 is approximately 1: 0.6. Therefore, the ratio of the increase in the volume of the pressurizing chamber 12 to the decrease in the volume of the variable volume chamber 30 is also 1: 0.6. For this reason, about 60% of the fuel sucked into the pressurizing chamber 12 is supplied from the variable volume chamber 30, and the remaining about 40% is sucked from the fuel inlet. Thereby, the fuel suction efficiency into the pressurizing chamber 12 is improved.

(2) Metering stroke When the plunger 21 moves up from the bottom dead center toward the top dead center in the cylinder hole 11 due to the rotation of the camshaft, the volume of the pressurizing chamber 12 decreases. At this time, since energization to the coil 611 is stopped until a predetermined time, the needle 67 and the suction valve 55 are positioned in the right direction in FIG. 1 by the urging force of the second spring 68. As a result, the supply passage 52 is kept open. For this reason, the low-pressure fuel once sucked into the pressurizing chamber 12 is returned to the supply passage 52. Therefore, the pressure in the pressurizing chamber 12 does not increase.

In the metering stroke, the volume of the variable volume chamber 30 increases as the plunger 21 rises. Therefore, the fuel in the damper chamber 40 flows into the variable volume chamber 30 via the return passage 33, the annular passage 32, and the cylindrical passage 31.
At this time, about 60% of the volume of the low-pressure fuel discharged from the pressurizing chamber 12 to the damper chamber 40 is sucked into the variable volume chamber 30 from the damper chamber 40. This reduces about 60% of the fuel pressure pulsation.

(3) Pressurization stroke The coil 611 is energized at a predetermined time while the plunger 21 rises in the cylinder hole 11 from the bottom dead center toward the top dead center. Then, a magnetic attractive force is generated between the fixed core 62 and the movable core 63 by the magnetic field generated in the coil 611. When the magnetic attraction force becomes larger than the difference between the elastic force of the second spring 68 and the elastic force of the first spring 57, the movable core 63 and the needle 67 move to the fixed core 72 side (left direction in FIG. 1). Thereby, the pressing force of the needle 67 against the suction valve 55 is released. The suction valve 55 moves to the seat portion 54 side by the elastic force of the first spring 57 and the force generated by the flow of low-pressure fuel discharged from the pressurizing chamber 12 to the damper chamber 40 side. Accordingly, the suction valve 55 is seated on the seat portion 54 and the supply passage 52 is closed.

From when the intake valve 55 is seated on the seat portion 54, the fuel pressure in the pressurizing chamber 12 increases as the plunger 21 rises toward the top dead center. In the discharge valve portion 70, the force that the upstream fuel pressure acts on the discharge valve member 82 of the discharge valve device 80 is the force that the downstream fuel pressure acts on the discharge valve member 82 and the spring 83. When larger than the urging force, the discharge valve member 82 opens from the seat portion 81. As a result, the high-pressure fuel pressurized in the pressurizing chamber 12 is discharged from the fuel outlet 72 via the discharge passage 71.
Note that energization of the coil 611 is stopped during the pressurization stroke. Since the force that the fuel pressure in the pressurizing chamber 12 acts on the suction valve 55 is larger than the urging force of the second spring 68, the suction valve 55 maintains the closed state.

The high-pressure pump 1 repeats the steps (1) to (3) to pressurize and discharge a required amount of fuel for the internal combustion engine.
If the timing of energizing the coil 611 is advanced, the time of the metering stroke is shortened and the time of the pressurizing stroke is lengthened. As a result, the amount of fuel returned from the pressurizing chamber 12 to the supply passage 52 decreases, and the amount of fuel discharged from the discharge passage 71 increases.
On the other hand, if the timing of energizing the coil 611 is delayed, the time of the metering stroke becomes longer and the time of the discharge stroke becomes shorter. Thereby, the fuel returned from the pressurizing chamber 12 to the supply passage 52 increases, and the fuel discharged from the discharge passage 71 decreases.
Thus, by controlling the timing of energizing the coil 611, the amount of fuel discharged from the high-pressure pump 1 is controlled to the amount required by the internal combustion engine.

Next, the effect of this embodiment is demonstrated.
In the high-pressure pump 1 of the present embodiment, the end surface 811 of the seat portion 81 that has been previously press-fitted into the medium inner diameter passage 712 from the fuel outlet 72 side is surrounded by the inclined portion 73 at the boundary between the medium inner diameter passage 712 and the large inner diameter passage 713. The inclined portion 73 has a linear taper shape in which the inner diameter of the inclined portion 73 decreases from the large inner diameter passage 713 on the fuel outlet 72 side toward the inner inner diameter passage 712 on the pressurizing chamber 12 side. The discharge valve member 82 inserted from the large-diameter passage 713 on the outlet 72 side toward the medium-inner-diameter passage 712 is adjusted in its insertion direction by the inclined portion 73, so the first end surface 821 of the discharge valve member 82 is seated on the sheet. It can be brought into contact with the end surface 811 of the portion 81 easily and accurately. That is, in the process in which the discharge valve member 82 is inserted from the large inner diameter passage 713 side toward the inner inner diameter passage 712 side, the sheet valve portion of the discharge valve member 82 is subjected to a centering action by the inclined portion 73 having a linear taper shape. Easy and accurate positioning with respect to 81 can be performed.

When the adjusting pipe 84 is inserted from the fuel outlet 72 side into the outlet-side first passage 714 and the large-inner-diameter passage 713, the outer peripheral surface of the outer peripheral surface is made to exit by pressing the large outer diameter portion 842 into the outlet-side first passage 714. Since the first end surface 821 of the discharge valve member 82 is fixed to the inner peripheral surface of the first side passage 714 by the biasing force of the spring 83 whose end is locked by the adjusting pipe 84, The end surface 811 can be appropriately biased. Therefore, the discharge valve device 80 can be easily and stably assembled to the discharge valve portion 70 in a state where the proper function is ensured.
Further, the adjusting pipe 84 accommodates the guide portion 824 of the discharge valve member 82 on its inner peripheral surface 843 and guides the reciprocating movement of the discharge valve member 82, thereby smoothing the reciprocating movement of the discharge valve member 82. The function of the discharge valve device 80 can be appropriately exhibited.

The adjusting pipe 84 has a communication hole 845 opened in the peripheral wall of the small outer diameter portion 841, thereby forming a space formed between the outer peripheral surface of the small outer diameter portion 841 and the inner peripheral surface of the large inner diameter passage 713. 74 and the space sandwiched between the inner peripheral surface 843 and the end surface of the guide portion 824 of the discharge valve member 82 on the fuel outlet 72 side are in communication, the discharge valve device 80 is opened, and the discharge valve member 82 is opened. When the first end surface 821 of the first seat 821 is separated from the end surface 811 of the seat portion 81, a smooth flow of high-pressure fuel from the pressurizing chamber 12 toward the fuel outlet 72 is ensured, and the function of the discharge valve device 80 is appropriately exhibited. Can be made.
Further, the adjusting pipe 84 has a stopper end 844 for restricting the maximum lift amount α when the discharge valve member 82 reciprocates, so that the function of the discharge valve device 80 can be exhibited appropriately and safely. Can do.

The stopper end 844 of the adjusting pipe 84, the maximum lift of the discharge valve member 82 alpha is between the upstream passage area A _IN and the maximum opening area A _S and the downstream passage area A _OUT, the following equation A _OUT <A _S <1.5 × A _IN
Therefore, the downstream passage area A _OUT becomes relatively small, and the pressure of the fuel downstream from the valve portion 823 of the discharge valve member 82 relatively increases. When the first end surface 821 of the valve member 82 is about to be seated on the end surface 811 of the seat portion 81, pressure is easily applied to the valve portion 823 of the discharge valve member 82 from the downstream side, and the valve closing speed of the discharge valve device 80 is increased. Can be raised.
Further, since the maximum opening area _AS is relatively small and the maximum lift amount α of the discharge valve member 82 is regulated to be small, and the lift of the discharge valve member 82 is suppressed more than necessary, the discharge valve member The moving distance of 82 is shortened, and the valve closing speed of the discharge valve device 80 can be increased.

(Second Embodiment)
FIG. 4 shows a state in which the discharge valve device is assembled to the discharge valve portion of the high-pressure pump according to the second embodiment of the present invention (valve closed state), and FIG. 5 shows the valve open state at the time of maximum lift of the discharge valve device. Show. In the following embodiments, the same reference numerals are given to substantially the same components as those in the first embodiment, and the description thereof is omitted.
First, the discharge valve portion 70 of the high-pressure pump 2 according to the present embodiment will be described with reference to FIGS. 4 and 5. In addition, since parts other than the discharge valve part 70 of the high-pressure pump 2 have the same configuration as the high-pressure pump 1 shown in FIG. 1 of the first embodiment, the description thereof is omitted.

As in the case of the first embodiment, the discharge passage 71 of the discharge valve portion 70 is formed in order from the pressurizing chamber 12 side toward the fuel outlet 72 side in order of a small inner diameter passage 711, an intermediate inner diameter passage 712, a large inner diameter passage 713, The outlet side first passage 714 and the outlet side second passage 715 are provided. And the discharge valve apparatus 80 is assembled | attached to the discharge passage 71 similarly to the case of the said 1st Embodiment.
However, unlike the inclined portion 73 having a linear taper shape in the case of the first embodiment, an inclined portion 73A having a step shape is formed at the boundary between the medium inner diameter passage 712 and the large inner diameter passage 713.

Next, a state in which the discharge valve device 80 is assembled to the discharge valve portion 70 of the high-pressure pump 2 will be described with reference to FIG. Note that the discharge valve device 80 itself has the same configuration as that of the first embodiment, and a description thereof will be omitted.
The state in which the discharge valve device 80 is assembled to the discharge valve portion 70 of the high-pressure pump 2 is basically the same as in the case of the first embodiment. However, a gap is formed between the inner peripheral surface of the staircase-shaped inclined portion 73A and the outer peripheral surface of the valve portion 823 of the discharge valve member 82, and both the peripheral surfaces are not in close contact with each other. This gap is a flow path when upstream high-pressure fuel flows downstream between the seat portion 81 and the valve portion 823 of the discharge valve member 82 when the discharge valve device 80 is opened. It is for securing.

Next, a method for assembling the discharge valve device 80 to the discharge valve portion 70 of the high-pressure pump 2 will be described.
First, the seat portion 81 is press-fitted into the inside inner diameter passage 712 from the fuel outlet 72 side so that the end surface 811 comes to a position surrounded by the inclined portion 73A.
Subsequently, the discharge valve member 82 is inserted into the large inner diameter passage 713 from the fuel outlet 72 side, and the first end surface 821 is brought into contact with the end surface 811 of the seat portion 81.

  At this time, the end surface 811 of the seat portion 81 is at a position surrounded by the inclined portion 73A at the boundary between the medium inner diameter passage 712 and the large inner diameter passage 713, and the inner diameter of the inclined portion 73A is the large inner diameter passage on the fuel outlet 72 side. The discharge valve member 82 inserted from the large-diameter passage 713 toward the medium-inner-diameter passage 712 has an inclined portion 73A. Accordingly, the insertion direction is adjusted, and the first end surface 821 of the discharge valve member 82 is brought into contact with the end surface 811 of the seat portion 81 easily and accurately. That is, the discharge valve member 82 is subjected to a centering action by the inclined portion 73A having a staircase shape in the process of being inserted from the large inner diameter passage 713 side toward the inner inner diameter passage 712 side. Easy and accurate positioning with respect to 81 is performed.

Subsequently, as in the case of the first embodiment, the spring 83 and the adjusting pipe 84 are sequentially inserted and accommodated.
Thus, by inserting the seat portion 81, the discharge valve member 82, the spring 83, and the adjusting pipe 84 sequentially into the discharge passage 71 from the fuel outlet 72 side, the end of the spring 83 whose end is locked to the adjusting pipe 84 is obtained. The discharge valve device 80 in which the first end surface 821 of the valve portion 823 of the discharge valve member 82 is urged against the end surface 811 of the seat portion 81 by the urging force is assembled to the discharge valve portion 70.
The operation of the discharge valve device 80 assembled to the discharge valve unit 70 and the operation of the high-pressure pump 2 are the same as in the case of the first embodiment, and a description thereof will be omitted.

Next, the effect of this embodiment is demonstrated.
This embodiment is different in that an inclined portion 73A having a step shape is formed on the inner wall portion of the discharge passage 71 instead of the inclined portion 73 having a linear taper shape of the first embodiment. However, when the discharge valve member 82 is inserted into the large inner diameter passage 713 from the fuel outlet 72 side and the first end surface 821 abuts against the end surface 811 of the seat portion 81, the inclined portion 73A forming a step shape has a linear taper shape. By performing the same alignment operation as that of the inclined portion 73 that forms the above, the discharge valve member 82 can be easily and accurately positioned with respect to the seat portion 81.
Therefore, the present embodiment can achieve the same effects as those of the first embodiment.

(Third embodiment)
FIG. 6 shows a state in which the discharge valve device is assembled to the discharge valve portion of the high-pressure pump according to the third embodiment of the present invention.
First, the high-pressure pump 3 according to the third embodiment will be described with reference to FIG.
The high pressure pump 3 is a cylinder separate type high pressure pump in which a cylinder hole is formed of a member different from the pump body 10. A cylinder forming member 90 separate from the pump body 10 includes a cylindrical cylinder hole, a pressurizing chamber 91 communicating with the cylinder hole, and a central axis of the cylinder hole communicating with the pressurizing chamber 91. A discharge passage 92 extending in a substantially vertical direction is integrally formed. The discharge passage 92 corresponds to a “first discharge passage” recited in the claims.

  A circular recess 93 having a predetermined depth and a flat bottom surface is formed on the outer wall of the cylinder forming member 90, and the discharge passage 92 passes through the center of the bottom surface of the recess 93. In addition, a recess 94 deeper than the depth of the recess 93 is formed in a circumferential shape on the outer wall around the recess 93 of the cylinder forming member 90 in contact with the recess 93. A portion of the outer wall portion of the cylinder forming member 90 that is sandwiched between the discharge passage 92 and the recess 94 is a sheet portion 95. Further, the bottom surface of the concave portion 93 becomes the end surface 951 of the sheet portion 95. For this reason, the end surface 951 of the sheet portion 95 formed in the discharge passage 92 has a shape protruding to the opposite side of the pressurizing chamber 91.

  The pump body 10 is formed with a discharge passage 71a that communicates with the discharge passage 92 and extends substantially perpendicular to the central axis of the cylinder hole. The discharge passage 71a corresponds to a “second discharge passage” recited in the claims. The discharge passage 71a is, in order from the pressurizing chamber 12 side toward the fuel outlet 72 side, a large inner diameter passage 713a having a larger inner diameter than the discharge passage 92, an outlet first passage 714a having a smaller inner diameter than the large inner diameter passage 713a, and an outlet The outlet side second passage 715a has a relatively larger inner diameter than the side first passage 714a.

At the boundary between the discharge passage 92 formed in the cylinder forming member 90 and the large inner diameter passage 713a formed in the pump body 10, the inner wall of the large inner diameter passage 713a, the outer wall of the cylinder forming member 90, and the cylinder forming member 90 An inclined portion 73 </ b> B that is formed of an inner wall of a recess 94 formed in the outer wall and has a stepped shape as a whole is formed. The inclined portion 73 </ b> B surrounds the end surface 951 of the seat portion 95 formed on the outer wall portion of the cylinder forming member 90.
In addition, since parts other than the cylinder forming member 90 and the discharge valve portion 70 of the high-pressure pump 3 have the same configuration as the high-pressure pump 1 shown in FIG. 1 of the first embodiment, description thereof is omitted.

Next, a state in which the discharge valve device 80A is assembled to the discharge valve portion 70 of the high-pressure pump 3 will be described with reference to FIG.
The discharge valve device 80A includes a seat portion 95, a discharge valve member 82, a spring 83, an adjusting pipe 84, and the like.
As described above, the seat portion 95 is formed on the outer wall portion of the cylinder forming member 90. The discharge valve member 82 is accommodated in the large inner diameter passage 713a of the discharge passage 71a, and the first end face 821 thereof is in contact with the end face 951 of the seat portion 95.

As in the case of the first embodiment, the spring 83 is accommodated in the large inner diameter passage 713a, one end of which is in contact with the second end surface 822 of the discharge valve member 82, and further, the large inner diameter passage 713 and An adjusting pipe 84 is press-fitted into the outlet-side first passage 714 and the other end of the spring 83 is locked. The first end surface 821 of the valve portion 823 of the discharge valve member 82 is urged against the end surface 951 of the seat portion 95 by the urging force of the spring 83 whose end is locked to the adjusting pipe 84. ing.
Thus, the discharge valve device 80A is assembled to the discharge valve portion 70.

Next, a method of assembling the discharge valve device 80A to the discharge valve portion 70 of the high-pressure pump 3 will be described.
Since the seat portion 95 is already formed on the outer wall portion of the cylinder forming member 90, first, the discharge valve member 82 is inserted into the large inner diameter passage 713 a from the fuel outlet 72 side, and the first end surface 821 is used as the end surface of the seat portion 95. 951 is contacted.

At this time, the end surface 951 of the sheet portion 95 is at a position surrounded by the inclined portion 73B at the boundary between the discharge passage 92 and the large inner diameter passage 713a, and the inner diameter of the inclined portion 73B is from the large inner diameter passage 713a on the fuel outlet 72 side. The discharge valve member 82 inserted toward the discharge passage 92 from the fuel outlet 72 side is inserted into the discharge passage 92 by the inclined portion 73B. The first end surface 821 of the discharge valve member 82 is in contact with the end surface 951 of the seat portion 95 easily and accurately. That is, in the process in which the discharge valve member 82 is inserted from the fuel outlet 72 side toward the discharge passage 92, it receives a centering action by the inclined portion 73B having a stepped shape, and as in the case of the second embodiment, Easy and accurate positioning of the discharge valve member 82 with respect to the seat portion 95 is performed.
Subsequently, as in the case of the second embodiment, the spring 83 and the adjusting pipe 84 are sequentially inserted and accommodated.

Thus, the discharge valve member 82, the spring 83, and the adjusting pipe 84 are sequentially inserted into the discharge passage 71a from the fuel outlet 72 side, so that the discharge is performed by the biasing force of the spring 83 whose end is locked to the adjusting pipe 84. The discharge valve device 80 </ b> A in which the first end surface 821 of the valve portion 823 of the valve member 82 is urged against the end surface 951 of the seat portion 95 is assembled to the discharge valve portion 70.
Since the operation of the discharge valve unit 70 to which the discharge valve device 80A is assembled and the operation of the high-pressure pump 3 are the same as those in the first embodiment, description thereof is omitted.

Next, the effect of this embodiment is demonstrated.
This embodiment is different in that an inclined portion 73B having another staircase shape is formed instead of the inclined portion 73A forming the staircase of the second embodiment.
Moreover, the high-pressure pump 3 of this embodiment has a different structure from the high-pressure pump 2 of the second embodiment. That is, the high-pressure pump 2 of the second embodiment uses a cylinder-integrated pump body, whereas the high-pressure pump 3 of the present embodiment has a cylinder body in which the pump body 10 and the cylinder forming member 90 are separate bodies. A body pump body is used.
Further, the discharge valve device 80A of the present embodiment is partly different from the discharge valve device 80 of the second embodiment. That is, the sheet portion 81 in the second embodiment is disposed in the discharge passage 71 of the pump body 10, whereas in the present embodiment, the sheet portion 95 is formed on the outer wall portion of the cylinder forming member 90. Is different.

However, in this embodiment, when the discharge valve member 82 is inserted from the fuel outlet 72 side toward the discharge passage 92 and the first end surface 821 abuts against the end surface 951 of the seat portion 95, the inclined portion forms a step shape. When 73B performs the same alignment operation as that of the inclined portion 73A of the second embodiment, the discharge valve member 82 can be easily and accurately positioned with respect to the seat portion 95.
Therefore, although this embodiment has a difference from the second embodiment as described above, the same operational effects as those of the second embodiment can be achieved. In other words, the present invention can be suitably applied to a high-pressure pump using a cylinder-integrated pump body and a high-pressure pump using a cylinder-separated pump body.

(Fourth embodiment)
FIG. 7 shows a state in which the discharge valve device is assembled to the discharge valve portion of the high-pressure pump according to the fourth embodiment of the present invention.
The discharge valve device 80B of the high-pressure pump 4 according to the fourth embodiment differs from the first embodiment only in the configuration of the adjusting pipe, particularly in the position of the communication hole. That is, the adjusting pipe 85 as a support member includes an inner peripheral surface 853 that guides the guide portion 824 of the discharge valve member 82, and a stopper end portion 854 for regulating the maximum lift amount when the discharge valve member 82 reciprocates. , And a communication hole 855 opened to the large outer diameter portion 852.
The communication hole 855 includes a space 74 formed between the outer peripheral surface of the small outer diameter portion 851 and the inner peripheral surface of the large inner diameter passage 713, the inner peripheral surface 853 of the adjusting pipe 85, and a guide for the discharge valve member 82. The space sandwiched between the end surface of the portion 824 on the fuel outlet 72 side is communicated.
Since the operational effects of the present embodiment are the same as the operational effects of the first embodiment, description thereof will be omitted.

(Other embodiments)
In the said 1st Embodiment, although the inclination part 73 has comprised the linear taper shape, you may make a parabolic taper shape other than linear, for example. In the second and third embodiments, the inclined portions 73A and 73B have different staircase shapes. In addition to the illustrated staircase shapes, various staircase shapes such as a staircase shape with rounded corners are used. It may be. In any case, the inclined portion may be in a position that surrounds the end surface of the seat portion, and may have a shape in which the inner diameter decreases from the fuel outlet side toward the pressurizing chamber side.

  In the first to fourth embodiments, the inner diameter of the outlet-side first passage 714 is smaller than the inner diameter of the large-inner-diameter passage 713. This is because the adjusting pipe 84 that is press-fitted into the outlet-side first passage 714 is used. It matches the outer diameter. For this reason, when the outer diameter of the press-fitting portion of the adjusting pipe 84 is increased, the inner diameter of the outlet-side first passage 714 is increased accordingly, and for example, the inner diameter may be the same as that of the large inner diameter passage 713.

1, 2, 3, 4 ... high pressure pump 10 ... pump body (cylinder forming member)
DESCRIPTION OF SYMBOLS 11 ... Cylinder hole 12 ... Pressurization chamber 13 ... Relief valve passage 14 ... Communication port 20 ... Plunger part 21 ... Plunger 30 ... Variable volume chamber 40 ... Damper chamber 50 ... Suction valve part 60 ... Electromagnetic drive part 70 ... Discharge valve part 71 ... Discharge passage (first discharge passage, second discharge passage)
71a ... discharge passage (second discharge passage)
711... Small inner diameter passage (first discharge passage, second discharge passage)
712 ... Medium inner diameter passage (second discharge passage)
713, 713a ... Large inner diameter passage (second discharge passage)
714, 714a... Outlet side first passage (second discharge passage)
715, 715a... Outlet side second passage (second discharge passage)
72: Fuel outlets 73, 73A, 73B ... Inclined portions 80, 80A, 80B ... Discharge valve devices 81, 95 ... Seat portions 811, 951 ... End faces 82 ... Discharge valve members 821・ ・ ・ First end surface 822 ・ ・ ・ Second end surface 823 ・ ・ ・ Valve part 824 ・ ・ ・ Guide part 83 ・ ・ ・ Spring (biasing member)
84, 85 ... Adjusting pipe (supporting member)
841, 851 ... Small outer diameter portions 842, 852 ... Large outer diameter portions 843, 853 ... Inner peripheral surfaces 844, 854 ... Stopper end portions 845, 855 ... Communication holes 90 ... Cylinder forming member 91 ... pressurizing chamber 92 ... discharge passage (first discharge passage)
93 ... concave part 94 ... hollow

Claims (10)

A plunger,
A cylindrical cylinder hole that accommodates the plunger so as to be reciprocally movable in the axial direction, communicated with the cylinder hole, pressurized chamber in which fuel is pressurized by the reciprocating movement of the plunger, communicated with the pressurized chamber, A cylinder forming member having a suction passage for sucking fuel into the pressurizing chamber, and a first discharge passage communicating with the pressurizing chamber and discharging high-pressure fuel pressurized in the pressurizing chamber;
A pump body having a second discharge passage communicating with the first discharge passage and discharging high-pressure fuel from the pressurizing chamber toward a fuel outlet;
A cylindrical sheet portion formed at a predetermined position of a discharge passage composed of the first discharge passage and the second discharge passage, and having an end surface facing the fuel outlet side;
An inclined portion formed on an inner wall portion of the discharge passage at a position surrounding the end surface of the sheet portion, and having an inner diameter that decreases from the fuel outlet side toward the pressurizing chamber side;
A discharge valve member inserted into the second discharge passage from the fuel outlet side and having a valve portion sandwiched between a first end surface and a second end surface, the first end surface being in contact with the end surface of the seat portion; ,
An urging member inserted into the second discharge passage from the fuel outlet side, and having one end abutting against the second end surface of the discharge valve member;
A high-pressure pump comprising: a cylindrical support member that is inserted into the second discharge passage from the fuel outlet side and abuts against the other end of the biasing member. The second discharge passage has a small inner diameter passage, a medium inner diameter passage, and a large inner diameter passage in order from the pressurizing chamber side to the fuel outlet side,
The seat portion is inserted into the inner diameter passage from the fuel outlet side,
The inclined portion is formed at a boundary between the medium inner diameter passage and the large inner diameter passage,
2. The discharge valve member is inserted into the large inner diameter passage from the fuel outlet side, and the first end surface abuts on the end surface of the seat portion at a position surrounded by the inclined portion. The high-pressure pump described in 1. The seat portion is formed on an outer wall portion of the cylinder forming member,
The inclined portion is formed at a boundary between the first discharge passage and the second discharge passage,
The discharge valve member is inserted into the second discharge passage from the fuel outlet side, and is in contact with the end surface of the seat portion at a position where the first end surface of the discharge valve member is surrounded by the inclined portion. The high-pressure pump according to claim 1, wherein   The high-pressure pump according to any one of claims 1 to 3, wherein the inclined portion has a tapered shape.   The high-pressure pump according to any one of claims 1 to 3, wherein the inclined portion has a step shape.   The high-pressure pump according to claim 1, wherein the support member is press-fitted into the second discharge passage. The discharge valve member has a guide portion extending from the valve portion to the second end surface side,
The support member is opened in an inner peripheral surface that guides the guide portion when the discharge valve member reciprocates and a wall surface, and the first end surface of the discharge valve member is separated from the end surface of the seat portion. The high-pressure pump according to any one of claims 1 to 6, further comprising a communication hole for allowing high-pressure fuel flowing from the pressurizing chamber toward the fuel outlet to pass therethrough.   The high pressure pump according to any one of claims 1 to 7, wherein the support member has an end portion serving as a stopper that regulates a maximum lift amount when the discharge valve member reciprocates. The discharge valve member has a guide portion extending from the valve portion to the second end surface side,
The support member is opened in an inner wall portion that guides the guide portion when the discharge valve member reciprocates, and a wall surface, and the first end surface of the discharge valve member is separated from the end surface of the seat portion. A communication hole for allowing high-pressure fuel flowing from the pressurizing chamber toward the fuel outlet, and an end serving as a stopper for restricting the maximum lift amount when the discharge valve member reciprocates. And
An inner diameter cross-sectional area of the seat portion and A _IN, the area of the opening formed between the valve portion of the discharge valve member and the seat portion when the discharge valve member has a maximum lift and A _S, When the area of the communication hole is A _OUT , the following formula: A _OUT <A _S <1.5 × A _IN
The high-pressure pump according to any one of claims 1 to 6, wherein the support member regulates a maximum lift amount of the discharge valve member so that the relationship is established.   The high-pressure pump according to any one of claims 1 to 9, wherein the cylinder forming member is continuously integrated with the pump body.

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