JP4968274B2 - Fuel supply pump - Google Patents

Description

  The present invention relates to a fuel supply pump including a fuel pressurizing chamber for increasing the pressure of fuel and a fuel intake valve for supplying fuel to the fuel pressurizing chamber.

  Conventionally, a valve body provided with a discharge port for discharging fuel into the fuel pressurizing chamber, a valve piston that is slidably held in the valve body, opens and closes the discharge port, and one end is held in the valve body. Patent Documents 1 and 2 disclose fuel supply pumps including a fuel intake valve having a spring that applies a biasing force in a direction in which a piston closes and a spring seat that holds the other end of the spring.

Japanese Patent Laid-Open No. 2004-21580 JP 2007-297994 A

  By the way, the spring seat is formed separately from the valve piston because the valve piston must be inserted into the discharge port. Therefore, after the valve piston is inserted into the discharge port, the valve piston and the spring seat must be fixed by some method.

  In the fuel supply pump disclosed in Patent Document 1, laser welding is employed as a method for fixing the valve piston and the spring seat. In order to perform such welding, it is necessary to select a material that can be easily welded as a material for forming the valve piston, that is, a material having a lower strength than a relatively high strength high carbon steel applied as a material for a tool. Don't be. Thereby, there existed a problem that durability of a valve piston fell.

  On the other hand, in the fuel supply pump shown in Patent Document 2, mechanical fixing by a predetermined stopper is adopted as a method for fixing the valve piston and the spring seat. In this way, the material for forming the valve piston can be freely selected by realizing the fixation between the valve piston and the spring seat not by welding but by a stopper. Thereby, durability of a valve piston can be improved by adopting, for example, high carbon steel as a material for forming the valve piston.

  By the way, in the fuel supply pump shown by patent document 2, the groove part for latching a stopper is provided in the valve piston, and the step part for latching a stopper is provided in the spring seat. At least one of the stopper and the groove and between the stopper and the step is provided with a gap for converting the shear stress acting on the stopper by the reciprocating motion of the valve piston into a compressive stress. It has been. If there is such a gap, the stopper is slid constantly between the groove and the step portion, so that there is a problem that the stopper is easily worn.

  Furthermore, the fuel supply pump shown in Patent Document 2 employs a C-ring as a stopper. When a C-ring is used as a stopper, the manufacturing cost may increase due to the complicated shape. Further, since the C-ring has an inner ring portion that is difficult to polish, the production cost may increase.

  Therefore, in view of the above problems, the present invention has an object to provide a fuel supply pump in which the wear resistance of a stopper for fixing a valve piston and a spring seat is improved, and the manufacturing cost of the stopper is reduced. To do.

In order to achieve the above object, the invention according to claim 1 is a fuel supply pump comprising a fuel pressurizing chamber for pressurizing fuel and a fuel intake valve for supplying fuel to the fuel pressurizing chamber. The fuel intake valve has a valve body provided with a discharge port for discharging fuel in a fuel pressurizing chamber, a valve piston that is slidably held by the valve body, and that opens and closes the discharge port. And a spring that applies a biasing force in the direction in which the valve piston closes, and a spring seat that holds the other end of the spring, and a valve that opens and closes the discharge port at the end of the valve piston on the spring seat side A through-hole penetrating in a direction perpendicular to the piston opening / closing direction is provided, and a rod-like stopper is inserted into the through-hole. The spring seat is formed by a spring and a stopper. Is sandwiched, is secured to the valve piston, stop and the spring seat is in surface contact, stop and the inner wall surface constituting the through hole is in surface contact, stop is formed by a bearing steel or carburized steel A gap is formed between the stopper and the inner wall surface constituting the through-hole so that the stopper can move in the opening and closing direction .

  Thus, according to the present invention, the spring seat is sandwiched between the one end of the spring and the stopper inserted in the through hole, and is fixed to the valve piston. Accordingly, a stopper is provided between the groove provided in the valve piston and the step provided in the spring seat, and at least one of the stopper and the groove and between the stopper and the step is provided. Compared to the conventional configuration in which a gap is provided, the stopper can be prevented from sliding between the valve piston and the spring seat. Thereby, the wear resistance of the stopper can be improved. Furthermore, since the wear of the stopper is suppressed, it is possible to suppress the dust of the stopper generated by the wear from being mixed into the fuel and reducing the cleanliness of the fuel.

  Moreover, the shape of the stopper is a rod shape. Therefore, compared with the conventional case in which a C-ring is used as a stopper, the shape of the stopper is simple, so that the manufacturing cost can be reduced. Further, unlike the C-ring, since it does not have an inner ring portion, polishing processing becomes easy. Thereby, manufacturing cost can be reduced.

  Further, the valve piston and the spring seat are mechanically fixed instead of welding. Therefore, the material for forming the valve piston and the spring seat can be freely selected. Thereby, durability of a valve piston and a spring seat can be improved by adopting material with comparatively high intensity, such as high carbon steel, as a forming material of a valve piston and a spring seat.

As described in claim 1, good structure and stop and the spring seat is in surface contact. According to this, compared with the structure which a stopper and a spring seat contact partially, the contact area of a stopper and a spring seat can be ensured. Thereby, the value of the pressure acting on the stopper and the spring seat can be reduced. In addition, since the contact area between the stopper and the spring seat can be secured, when the stopper and the spring seat are separated from each other, the area that receives the negative pressure generated between the stopper and the spring seat can be increased. it can. Thereby, it can suppress that a stopper and a spring seat leave | separate by the inertial force by the reciprocating motion of a valve piston. That is, the stopper and the spring seat have relatively different speeds, and it is possible to suppress the occurrence of striking force between the stopper and the spring seat. As described above, breakage of the stopper can be suppressed.

As described in claim 1, it is preferable that the stopper and the inner wall surface constituting the through hole are in surface contact. According to this, compared with the structure which a stopper and an inner wall surface contact partially, the contact area of a stopper and an inner wall surface can be ensured. Thereby, the value of the pressure acting on the stopper and the inner wall surface can be reduced. In addition, since the contact area between the stopper and the inner wall surface can be secured, when the stopper and the inner wall surface are separated from each other, it is possible to increase the area that receives the negative pressure generated between the stopper and the inner wall surface. it can. Thereby, it can suppress that a stopper and an inner wall face separate by the inertial force by the reciprocating motion of a valve piston. That is, the stopper and the inner wall surface have relatively different speeds, and it is possible to suppress the occurrence of striking force between the stopper and the inner wall surface. As described above, breakage of the stopper can be suppressed.

As described in claim 1 , the stopper may be formed of bearing steel or a carburized material. Thereby, the intensity | strength of a stopper can be raised and the damage of a stopper can be suppressed.

As described in claim 1 , it is preferable that a gap is formed between the stopper and the inner wall surface constituting the through hole so that the stopper can move in the opening and closing direction. When there is no gap between the stopper and the inner wall surface that forms the through hole, for example, when the stopper is press-fitted into the through hole, the valve seat moves when the valve piston moves back and forth. There is a possibility that the stopper and the spring seat may be separated without being able to follow. When the stopper and the spring seat are separated from each other, a hitting force is generated between the stopper and the spring seat, and the stopper may be damaged.

On the other hand, the invention described in claim 1 has a configuration in which a gap is formed between the stopper and the inner wall surface. Even in this case, the stopper and the spring seat may be separated. However, since the stopper is sandwiched between the spring seat and the inner wall surface of the through hole, when the stopper and the spring seat are separated from each other, the stopper is separated from the inner wall surface. Therefore, since the stopper follows the separation of the spring seat, the distance between the stopper and the spring seat is shortened. Thereby, the relative speed of the stopper and the spring seat is increased, and it is possible to suppress an increase in the striking force acting on the stopper.

According to a second aspect of the present invention, the stopper is preferably sandwiched between the inner wall surface and the spring seat and held slidably in the through direction of the through hole. When the valve piston reciprocates, shearing stress due to the inner wall surface forming the through hole and the spring seat acts on the stopper. This shear stress continuously acts on the same location of the stopper when the stopper is fixed in the penetration direction. Therefore, there is a possibility that the part where the shear stress is constantly applied is exhausted and the stopper is broken.

On the other hand, the invention according to claim 2 is configured such that the stopper is slidable in the penetrating direction. Therefore, it is suppressed that a shear stress acts on the same location. Thereby, damage to the stopper due to shear stress can be suppressed.

According to a third aspect of the present invention, the spring seat is annular, and the outer ring portion of the spring seat is provided with a first protrusion that protrudes in the valve closing direction of the valve piston, and the first protrusion A configuration in which both ends of the stopper are held is preferable.

  The stopper is slidable in the penetrating direction, and excessive movement of the stopper in the penetrating direction (moving so that the stopper is pulled out from the through hole) lubricates the sliding portion of the fuel inflow valve. In the case of a configuration that is restrained by the inner wall surface of the holder part that stores fuel as a lubricant, the stopper and the holder part collide with each other, so that the stopper and the holder part may be damaged. Further, the inner wall surface of the holder portion is scraped by the stopper, and a part of the shaved inner wall surface may be mixed into the fuel, which may reduce the cleanliness of the fuel.

On the other hand, the invention according to claim 3 has a configuration in which the movement of the stopper in the penetrating direction is suppressed by the first projecting portion provided in the outer ring portion of the spring seat. Thereby, damage to a stopper and a holder part and the fall of the cleanliness of a fuel are suppressed.

In addition, since the effect of the invention of Claim 4 and 5 is the same as the effect of the invention of Claim 3 , the description is abbreviate | omitted.

It is sectional drawing which shows schematic structure of the fuel supply pump which concerns on 1st Embodiment. FIG. 2 is an enlarged cross-sectional view of a fuel intake valve in the fuel supply pump shown in FIG. 1. It is sectional drawing which follows the III-III line | wire shown in FIG. It is sectional drawing which shows schematic structure of the fuel intake valve which concerns on 2nd Embodiment. It is sectional drawing which shows schematic structure of the fuel intake valve which concerns on 3rd Embodiment. It is sectional drawing which shows the modification of a fuel intake valve.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
(First embodiment)
FIG. 1 is a cross-sectional view illustrating a schematic configuration of the fuel supply pump according to the first embodiment. FIG. 2 is an enlarged sectional view of the fuel intake valve in the fuel supply pump shown in FIG. 3 is a cross-sectional view taken along the line III-III shown in FIG. In the following, the direction in which the discharge port 34a of the valve piston 31 is opened and closed is referred to as the open / close direction, and the direction in which the discharge port 34a is closed in the open / close direction is simply closed as indicated by the white arrow in FIG. The direction of opening the discharge port 34a is simply referred to as the valve opening direction. A direction perpendicular to the opening / closing direction is referred to as a penetration direction.

  As shown in FIG. 1, the fuel supply pump 100 pressurizes the fuel supplied to the fuel pressurizing chamber 16 and supplies the pressurized fuel to the engine and the fuel pressurizing chamber 16. And a fuel intake valve 30 for supplying fuel. The fuel is supplied to the fuel intake valve 30 by a feed pump (not shown) that draws fuel from the fuel tank.

  As shown in FIG. 1, the high-pressure pump 10 includes a cam shaft 11 that is rotationally driven by a driving force of an engine output shaft, a cam 12 that rotates by the rotation of the cam shaft 11, and a rotational motion of the cam 12. A cam ring 13 that moves up and down; a plunger 15 that reciprocates within the cylinder 14 by the vertical movement of the cam ring 13; a fuel pressurization chamber 16 that varies in pressure by the reciprocation of the plunger 15; A cam ring 13, a cam 12, and a housing 17 that houses the cam shaft 11.

  The cam shaft 11 is slidably held by the housing 17 via the metal bush 18, and the cam ring 13 is slidably held by the cam 12 via the metal bush 18. Accordingly, the cam shaft 11 is rotatable with respect to the housing 17, and the cam ring 13 is movable up and down relatively with respect to the cam 12.

  A tappet 19 is integrally provided at the end of the plunger 15 on the cam ring 13 side, and a first spring 20 is provided between the tappet 19 and the inner wall surface of the housing 17. The plunger 15 is pressed and fixed to the outer peripheral surface of the cam ring 13 by the urging force of the first spring 20, and reciprocates in conjunction with the vertical movement of the cam ring 13.

  As shown in FIGS. 2 and 3, the fuel intake valve 30 reciprocates in the opening and closing direction to apply a biasing force in the direction in which the valve piston 31 closes and opens and closes the discharge port 34a. The second spring 32, the spring seat 33 that receives one end of the second spring 32, the valve body 34 that holds the valve piston 31 slidably and receives the other end of the second spring 32, and the fuel inflow valve 30. And a holder portion 35 for storing fuel as a lubricant for lubricating the sliding portion. In the present embodiment, the valve piston 31 and the valve body 34 are made of high carbon steel, and the spring seat 33 and the holder portion 35 are made of medium carbon steel. The second spring 32 corresponds to the spring described in the claims.

  As shown in FIG. 2, the valve piston 31 has a needle shape along the opening and closing direction, and has a collar portion 36 that closes the discharge port 34a at the end portion 31a on the valve opening direction side. Is provided, and a through hole 31c penetrating along the penetrating direction is provided at the end 31b on the valve closing direction side. As shown in FIG. 3, the inner wall surface 31d constituting the through hole 31c has a circular cross section with respect to the penetrating direction, and comes into surface contact with the facing surface 37a of the stopper 37 facing the inner wall surface 31d. .

  The valve piston 31 reciprocates due to the pressure fluctuation of the fuel pressurizing chamber 16 caused by the reciprocating motion of the plunger 15 and the biasing force of the second spring 32, and opens and closes the discharge port 34a. When the pressure of the fuel pressurizing chamber 16 is increased by the plunger 15 and the above-described urging force is larger than the pressure difference between the fuel pressurizing chamber 16 and the fuel storage portion 34b provided in the valve body 34, the discharge port 34a The collar portion 36 is pressed and the discharge port 34a is closed. On the other hand, when the pressure of the fuel pressurizing chamber 16 is reduced by the plunger 15 and the above-described urging force is smaller than the pressure difference between the fuel pressurizing chamber 16 and the fuel storage portion 34b, the flange portion 36 extends from the discharge port 34a. Are separated, and the discharge port 34a is opened. Thus, the valve piston 31 is reciprocated in conjunction with the reciprocating motion of the plunger 15, and the discharge port 34 a is opened and closed in conjunction with the reciprocating motion of the valve piston 31. The fuel stored in the fuel storage portion 34b is supplied to the fuel pressurizing chamber 16 by opening and closing the discharge port 34a.

  A minute gap is formed between the valve piston 31 and the valve body 34 so that the valve piston 31 can slide, and the flange portion 36 of the valve piston 31 and the discharge port 34a are separated from each other. In this state (the state where the discharge port 34a is opened), the valve piston 31 moves in a direction other than the opening / closing direction within the above-described gap. Therefore, an inertial force along a direction other than the opening / closing direction is applied to the stopper 37 described later, in addition to the penetrating force along the opening / closing direction by the valve piston 31.

  The spring seat 33 receives one end of the second spring 32 and transmits the urging force of the second spring 32 to the valve piston 31. As shown in FIG. 2, the spring seat 33 has an annular shape and is fixed to the valve piston 31 so that the inner peripheral surface of the inner ring portion faces the outer peripheral surface of the valve piston 31. Further, the surface 33 a facing the stopper 37 in the spring seat 33 is processed into a flat shape, and is in surface contact with the surface 37 b facing the spring sheet 33 in the stopper 37.

  The stopper 37 fixes the spring seat 33 to the valve piston 31 and is made of high carbon steel. As shown in FIG.2 and FIG.3, the stopper 37 is rod-shaped and the cross section with respect to the penetration direction has a kamaboko shape. That is, the opposing surface 37a is a curved surface along the inner wall surface 31d, and the opposing surface 37b is flat. Thereby, the opposing surface 37a and the inner wall surface 31d are in surface contact, and the opposing surface 37b and the spring seat 33 are in surface contact.

  Further, the stopper 37 is sandwiched between the spring seat 33 and the inner wall surface 31d, and is configured to be slidable in the penetrating direction. As described above, the stopper 37 has not only the inertia force in the opening / closing direction due to the reciprocating motion of the valve piston 31 in the opening / closing direction, but also the inertia force other than the opening / closing direction due to the movement other than the opening / closing direction of the valve piston 31. Acted. Therefore, since the inertia force in the penetration direction is applied to the stopper 37, the stopper 37 moves in the penetration direction. In addition, excessive movement in the penetration direction in the stopper 37 (movement so that the stopper 37 falls out of the through hole 31 c) is suppressed by the inner wall surface of the holder portion 35. As shown in FIG. 2, the length of the stopper 37 in the longitudinal direction is longer than the length from the opening of the through hole 31 c to the holder portion 35.

  As shown in FIGS. 2 and 3, a predetermined gap is provided between the stopper 37 and the inner wall surface 31 d so that the stopper 37 can move in the opening and closing direction. That is, the longest diameter along the opening / closing direction of the stopper 37 and the longest diameter along the direction perpendicular to the opening / closing direction and the penetrating direction are configured to be shorter than the diameter of the through hole 31c. Accordingly, even when the spring seat 33 is separated from the stopper 37 because the restoring force of the second spring 32 cannot follow the reciprocating movement of the valve piston 31 due to the intense reciprocation of the valve piston 31, Unlike the structure fixed to the valve piston 31, the stopper 37 is separated following the separation of the spring seat 33. Therefore, the separation distance between the spring seat 33 and the stopper 37 can be shortened as compared with the configuration in which the stopper 37 is press-fitted into the valve piston 31.

  Next, the process of fixing the spring seat 33 to the valve piston 31 will be described. First, the valve piston 31 is installed in the valve body 34 by inserting the valve piston 31 into the discharge port 34 a provided in the valve body 34 from the valve opening direction to the valve closing direction. Next, the second spring 32 and the spring seat 33 are inserted into the valve piston 31. Then, the stopper 37 is inserted into the through hole 31c in a state where the second spring 32 and the spring seat 33 are pressed against the valve body 34 side so that the opening of the through hole 31c is exposed. Finally, by releasing the force applied to the second spring 32 and the spring seat 33, the spring seat 33 is sandwiched between the second spring 32 and the stopper 37 and fixed to the valve piston 31.

  Next, the function and effect of the fuel supply pump 100 according to this embodiment will be described. As described above, the spring seat 33 is clamped by the second spring 32 and the stopper 37 inserted into the through hole 31 c and fixed to the valve piston 31. Accordingly, a stopper is provided between the groove provided in the valve piston and the step provided in the spring seat, and at least one of the stopper and the groove and between the stopper and the step is provided. Compared to the conventional configuration in which a gap is provided, the stopper 37 can be prevented from sliding between the valve piston 31 and the spring seat 33. Thereby, the abrasion resistance of the stopper 37 can be improved. Furthermore, since the wear of the stopper 37 is suppressed, it is possible to suppress the dust of the stopper 37 generated by the wear from being mixed into the fuel and reducing the cleanliness of the fuel.

  Further, the stopper 37 has a rod shape. Therefore, the shape of the stopper 37 is simpler than that in the prior art in which a C-ring is adopted as the stopper, so that the manufacturing cost can be reduced. Further, unlike the C-ring, since it does not have an inner ring portion, polishing processing becomes easy. Thereby, manufacturing cost can be reduced.

  Further, the valve piston 31 and the spring seat 33 are mechanically fixed instead of welding. Therefore, the material for forming the valve piston 31 and the spring seat 33 can be freely selected. Thereby, as employ | adopted by this embodiment, durability of the valve piston 31 can be improved by employ | adopting comparatively high strength materials, such as high carbon steel, as a forming material of the valve piston 31. FIG.

  In the present embodiment, the facing surface 37b of the stopper 37 facing the spring seat 33 and the facing surface 33a of the spring seat 33 facing the stopper 37 are in surface contact. According to this, the contact area between the stopper 37 and the spring seat 33 is smaller than the configuration in which the surface of the stopper facing the spring seat and the surface of the spring seat facing the stopper partially contact each other. Can be secured. Thereby, the value of the pressure acting on the stopper 37 and the spring seat 33 can be reduced. Further, since the contact area between the stopper 37 and the spring seat 33 can be secured, when the stopper 37 and the spring seat 33 are separated from each other, a negative pressure generated between the stopper 37 and the spring seat 33 is received. The area can be increased. Thereby, it is possible to suppress the stopper 37 and the spring seat 33 from separating due to the inertial force due to the reciprocating motion of the valve piston 31. In other words, the stopper 37 and the spring seat 33 have relatively different speeds, and it is possible to prevent the striking force from being generated on the stopper 37 and the spring seat 33. As described above, breakage of the stopper 37 can be suppressed.

  In this embodiment, the surface 37a facing the inner wall surface 31d of the stopper 37 and the inner wall surface 31d constituting the through hole 31c are in surface contact. According to this, the contact area of the stopper 37 and the inner wall surface 31d is ensured as compared with the configuration in which the surface of the stopper facing the inner wall surface and the inner wall surface constituting the through hole are in partial contact. be able to. Thereby, the value of the pressure acting on the stopper 37 and the inner wall surface 31d can be reduced. In addition, since the contact area between the stopper 37 and the inner wall surface 31d can be secured, when the stopper 37 and the inner wall surface 31d are separated from each other, a negative pressure generated between the stopper 37 and the inner wall surface 31d is received. The area can be increased. Thus, the stopper 37 and the inner wall surface 31d can be prevented from separating due to the inertial force due to the reciprocating motion of the valve piston 31. That is, the stopper 37 and the inner wall surface 31d have relatively different speeds, and it is possible to suppress the occurrence of striking force between the stopper 37 and the inner wall surface 31d. As described above, breakage of the stopper 37 can be suppressed.

  In the present embodiment, a predetermined gap is provided between the stopper 37 and the inner wall surface 31d so that the stopper 37 can move in the opening and closing direction. When there is no gap as described above, for example, when the stopper 37 is press-fitted into the through hole 31c, if the valve piston 31 reciprocates violently, the spring seat 33 (second spring 32) cannot follow the movement of the valve piston 31. In addition, the stopper 37 and the spring seat 33 may be separated from each other. When the stopper 37 and the spring seat 33 are separated from each other, a hitting force is generated on the stopper 37 and the spring seat 33, and the stopper 37 may be damaged.

  On the other hand, in this embodiment, a predetermined gap is formed between the stopper 37 and the inner wall surface 31d. Even in this case, the stopper 37 and the spring seat 33 may be separated. However, since the stopper 37 is sandwiched between the spring sheet 33 and the inner wall surface 31d, when the stopper 37 and the spring sheet 33 are separated from each other, the stopper 37 is also separated from the inner wall surface 31d. Therefore, since the stopper 37 follows the separation of the spring seat 33, the distance at which the stopper 37 and the spring seat 33 are separated is shortened. As a result, the relative speed between the stopper 37 and the spring seat 33 is increased, and the impact force acting on the stopper 37 can be suppressed from increasing.

  In the present embodiment, the stopper 37 is made of high carbon steel as bearing steel. Thereby, the intensity | strength of the stopper 37 is raised and damage to the stopper 37 is suppressed. In addition, as a forming material of the stopper 37, it is not limited to the said example, For example, a carburizing material can also be employ | adopted.

  In the present embodiment, the stopper 37 is sandwiched between the spring seat 33 and the inner wall surface 31d and is slidable in the penetrating direction. When the valve piston 31 reciprocates, shearing stress due to the inner wall surface 31 d and the spring seat 33 acts on the stopper 37. This shear stress is constantly applied to the same portion of the stopper 37 in the case where the stopper 37 is fixed in the penetrating direction. Therefore, there is a possibility that the part where the shear stress is constantly applied is exhausted and the stopper 37 is damaged.

  On the other hand, in this embodiment, the stopper 37 is configured to be slidable in the penetrating direction. Therefore, it is suppressed that a shear stress acts on the same location. Thereby, breakage of the stopper 37 due to shear stress can be suppressed.

(Second Embodiment)
Next, a second embodiment of the present invention will be described based on FIG. FIG. 4 is a sectional view showing a schematic configuration of the fuel intake valve according to the second embodiment, and corresponds to FIG. 2 shown in the first embodiment.

  Since the fuel supply pump according to the second embodiment is often in common with that according to the first embodiment, the detailed description of the common parts will be omitted below, and different parts will be described with emphasis. In addition, the same code | symbol shall be provided to the element same as the element shown in 1st Embodiment.

  In the first embodiment, the example in which the movement of the stopper 37 in the penetrating direction is suppressed by the inner wall surface of the holder portion 35 has been described. In contrast, the present embodiment is characterized in that the movement of the stopper 37 in the penetrating direction is suppressed by the spring seat 33.

  As shown in FIG. 4, the spring seat 33 according to the present embodiment is formed in an annular shape as in the first embodiment. However, the outer ring portion of the spring seat 33 is provided with a first protruding portion 33b that protrudes from the facing surface 33a in the valve closing direction along the outer periphery of the outer ring portion. Then, both ends of the stopper 37 are held by the first projecting portion 33b. Thus, in this embodiment, when the stopper 37 tries to move in the penetration direction, the stopper 37 is configured to be hooked on the first projecting portion 33b.

  As described above, in the fuel supply pump 100 shown in the first embodiment, the movement of the stopper 37 in the penetrating direction is suppressed by the inner wall surface of the holder portion 35. In the case of such a configuration, the stopper 37 and the holder part 35 collide with each other, so that the stopper 37 and the holder part 35 may be damaged. Further, the inner wall surface of the holder portion 35 is shaved by the stopper 37, and a part of the shaved inner wall surface may be mixed into the fuel, which may reduce the cleanliness of the fuel.

  On the other hand, in the fuel supply pump 100 according to the present embodiment, the movement of the stopper 37 in the penetrating direction is suppressed by the first projecting portion 33 b provided in the outer ring portion of the spring seat 33. Thereby, the collision with the stopper 37 and the holder part 35 is suppressed, and the damage of the stopper 37 and the holder part 35 and the fall of the cleanliness of a fuel are suppressed.

(Third embodiment)
Next, a third embodiment of the present invention will be described with reference to FIG. FIG. 5 is a cross-sectional view showing a schematic configuration of the fuel intake valve according to the third embodiment, and corresponds to FIG. 2 shown in the first embodiment and FIG. 4 shown in the second embodiment.

  Since the fuel supply pump according to the third embodiment is often in common with those according to each of the above-described embodiments, detailed description of the common parts will be omitted, and different parts will be described mainly. In addition, the same code | symbol shall be provided to the element same as the element shown to each above-mentioned embodiment.

  In 2nd Embodiment, the example in which the movement to the penetration direction of the stopper 37 was suppressed by the spring seat 33 was shown. On the other hand, the present embodiment is characterized in that the movement of the stopper 37 in the penetrating direction is suppressed by the second protrusion 37c provided in the stopper 37 as shown in FIG.

  As shown in FIG. 5, the stopper 37 according to the present embodiment is formed in a rod shape as in the first embodiment. However, the both ends of the stopper 37 are provided with second projecting portions 37c that project from the facing surface 37b in the valve opening direction. A part of the outer ring portion of the spring seat 33 is held by the second protrusion 37c. Thus, when the stopper 37 tries to move in the penetrating direction, the second projecting portion 37c is configured to be caught by the spring seat 33 inserted into the valve piston 31, so that the stopper 37 moves in the penetrating direction. Is suppressed. As described above, the same function and effect as those described in the second embodiment can be obtained.

  In addition, as a structure by which the movement to the penetration direction of the stopper 37 is suppressed by the protrusion part provided in the stopper 37, it is not limited to the said example. For example, as shown in FIG. 6, a third protrusion 37 d that protrudes from the facing surface 37 b in the valve opening direction is provided at a portion of the stopper 37 that is inserted into the through hole 31 c, and the third protrusion 37 d is A configuration held by the inner ring portion of the spring seat 33 can be employed. Also in this case, when the stopper 37 tries to move in the penetrating direction, the third protrusion 37d is configured to be caught by the spring seat 33 inserted into the valve piston 31, so that the stopper 37 moves in the penetrating direction. Is suppressed. FIG. 6 is a cross-sectional view showing a modification of the fuel intake valve.

  The preferred embodiments of the present invention have been described above. However, the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the spirit of the present invention.

  In the present embodiment, an example in which the stopper 37 has a rod shape and the cross-sectional shape with respect to the penetrating direction is a kamaboko shape. However, the cross-sectional shape of the stopper 37 is not limited to the above example, and for example, a semicircular shape can be adopted.

  In the present embodiment, an example in which a predetermined gap is formed between the stopper 37 and the inner wall surface 31d is shown. However, there may be no gap between the stopper 37 and the inner wall surface 31d. That is, a configuration in which the stopper 37 is press-fitted into the through hole 31c can be employed.

DESCRIPTION OF SYMBOLS 10 ... High pressure pump 16 ... Fuel pressurization chamber 30 ... Fuel intake valve 31 ... Valve piston 32 ... Second spring 33 ... Spring seat 37 ... Stopper 100 ... Fuel supply pump

Claims (5)

In a fuel supply pump comprising: a fuel pressurizing chamber that pressurizes fuel; and a fuel intake valve that supplies fuel to the fuel pressurizing chamber;
The fuel intake valve includes a valve body provided with a discharge port for discharging fuel into the fuel pressurizing chamber, a valve piston that is slidably held in the valve body and opens and closes the discharge port, and the valve body One end is held by the spring, and a spring that applies a biasing force in a direction in which the valve piston closes, and a spring seat that holds the other end of the spring,
A through hole penetrating in a direction perpendicular to the opening and closing direction of the valve piston for opening and closing the discharge port is provided at an end of the valve piston on the spring seat side, and a rod-shaped stopper is provided in the through hole. Inserted,
The spring seat is sandwiched between the spring and the stopper, and is fixed to the valve piston ,
The stopper and the spring seat are in surface contact,
The stopper and the inner wall surface constituting the through hole are in surface contact,
The stopper is formed of bearing steel or carburized material,
A fuel supply pump characterized in that a gap is formed between the stopper and an inner wall surface constituting the through hole so that the stopper can move in the opening and closing direction . 2. The fuel supply pump according to claim 1 , wherein the stopper is sandwiched between the inner wall surface and the spring seat and is slidably held in a penetrating direction of the through hole . The spring seat is annular;
The outer ring portion of the spring seat is provided with a first protrusion that protrudes in the valve closing direction of the valve piston,
Fuel supply pump according to claim 1, by the first projecting portion, both end portions of the stopper is characterized in that it is held. The spring seat is annular;
A second protrusion that protrudes in the valve opening direction of the valve piston is provided at both ends of the stopper,
By the second protruding portion, the fuel supply pump according to claim 1, wherein a portion of the outer annular portion of the spring seat is held. The spring seat is annular;
A third protrusion that protrudes in the valve opening direction of the valve piston is provided at a portion of the stopper inserted into the through hole.
2. The fuel supply pump according to claim 1 , wherein the third projecting portion is held by an inner ring portion of the spring seat .

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