JP2011117429A - High pressure pump - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a high pressure pump which sufficiently suppresses pulsation even when the flow of fuel returned to a fuel gallery is increased. <P>SOLUTION: The major portion of fuel in fast flow is led to a lid 14 by an extension region R. In other words, the main flow of the fuel is led to the lid 14 when the flow is increased. The fuel led to the lid 14 proceeds along the inner surface of the lid 14, impinges on the fuel impingement wall 14b of the flow change part 14a, and impinges on a diaphragm 34 at the lid side composing a damper member 35 after changing direction thereof. Namely, a fuel flow heading for the center portion of a movable part of the diaphragm 34 is created by the flow change part 14a. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a high-pressure pump used in an internal combustion engine (hereinafter referred to as “engine”).

  A high-pressure pump used for an engine includes a plunger that reciprocates by rotation of a camshaft. The operation of the high-pressure pump is specifically the intake stroke in which fuel is sucked from the fuel gallery in the pump into the pressurizing chamber when the plunger moves from top dead center to bottom dead center, and the plunger moves from bottom dead center to top dead center. Are roughly divided into a metering stroke in which a part of the low-pressure fuel is returned to the fuel gallery and a pressurization stroke in which the fuel is pressurized by a plunger toward the top dead center after closing the intake valve.

  Here, when the plunger is operated, pressure pulsation occurs. For example, when the engine speed increases and the camshaft speed increases, the plunger reciprocates at high speed. As a result, the change in the fuel pressure inside the fuel gallery becomes extremely large, resulting in large pulsations. Note that the pulsation does not depend only on the engine speed but can occur due to various factors.

  Therefore, conventionally, a high-pressure pump has been proposed in which a damper member called a pulsation damper is disposed in the fuel gallery to attenuate fuel pulsation (see, for example, Patent Document 1).

  This type of damper member is formed, for example, by welding a peripheral portion of a metal diaphragm. Here, the diaphragm has a thin plate shape, and the expansion and contraction of the damper member is realized by the pressure of the gas sealed inside and the external fuel pressure, and the pulsation of the fuel is suppressed. For example, in the metering step, the pressure in the fuel gallery is increased by returning the fuel in the pressurized chamber to the fuel gallery, so that the damper member contracts and suppresses the fuel pressure increase.

Japanese Patent No. 4036153

  By the way, in the above-mentioned patent document 1, since the flow path to the upper side of the damper has a shape in which the flow path area is restricted by the damper support member and the lid member, the pressure side connecting the pressurizing chamber and the fuel gallery. Most of the fuel returned from the passage to the fuel gallery flows into the lower side of the damper (see, for example, FIG. 3 of Patent Document 1). In this configuration, since the opening of the inlet is provided on the lower side of the damper, if the flow of the fuel flowing into the lower side becomes faster, before the damper contracts, that is, before the pressure increase of the fuel is suppressed, There is a risk that the fuel will reach the opening of this. In such a case, fuel pulsation is transmitted to the fuel pipe and the pipe support member. As a result, abnormal noise may occur. Occurrence of abnormal noise makes the driver feel uncomfortable and leads to deterioration of sensitivity quality. Further, if resonance occurs somewhere in the pipe support member, the pipe support member may be damaged.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a high-pressure pump capable of sufficiently suppressing pulsation when the flow of fuel returned to the fuel gallery becomes faster. There is to do.

  In the high-pressure pump according to claim 1, the pressurizing side passage connects the fuel gallery to the pressurizing chamber. Here, the fuel gallery has an opening of a fuel inlet (hereinafter referred to as “inlet”) for supplying fuel. In the pressurizing chamber, the fuel is pressurized. The plunger creates the volume change of the pressurizing chamber.

  The damper member is constituted by a diaphragm and is disposed inside the fuel gallery. And the change of the fuel pressure inside a fuel gallery is suppressed. The lid is assembled at a predetermined position of the housing to form the fuel gallery.

  Here, in particular, in the present invention, the pressure side passage and the lid portion are arranged so that the flow of fuel along the lid portion is created by the flow of fuel returned from the pressure side passage to the fuel gallery by the plunger. The speed of the flow of fuel from the pressure side passage to the fuel gallery is not constant and varies depending on the moving speed of the plunger. Therefore, when the moving speed of the plunger increases with an increase in the engine speed, a fuel flow along the lid is created. And the flow of the fuel which goes to the movable part of the diaphragm of a damper member is produced by the flow change part. Further, the “diaphragm movable portion” in the present invention refers to a portion that is displaced by the fuel pressure inside the fuel gallery, assuming that the fuel inlet pressure is supplied when the high-pressure pump is normally operating.

  In this way, most of the fast-flowing fuel is guided to the lid. In other words, the main flow of fuel when the flow becomes faster is actively guided to the lid. The fuel guided to the lid part is guided to the movable part of the diaphragm constituting the damper member by the flow changing part.

  That is, in the present invention, the main flow of the fuel is first brought along the lid portion and then introduced into the movable portion of the diaphragm. As a result, most of the fuel passes through the lid, so that the fuel that flows directly into the inlet can be reduced as much as possible. Further, for example, in the case of a two-sheet diaphragm, the diaphragm on the lid side can be sufficiently moved, and the damper member can sufficiently function. As a result, pulsation can be sufficiently suppressed, for example, when the flow of fuel returned to the fuel gallery becomes faster.

  As a specific configuration, as shown in claim 2, it is conceivable that the extension region of the pressure side passage assumed in the fuel gallery extends toward the lid. The extension region is a region where the pressurization side passage is extended, and is a region where the flow of fuel returned from the pressurization chamber to the fuel gallery by the plunger can be accelerated. The reason that “it can be faster” is because “it becomes faster” depending on conditions such as the engine speed.

  By the way, from the viewpoint of suppressing the pulsation, as shown in claim 3, the plunger changes the volume of the pressurizing chamber and forms a variable volume chamber whose volume changes with the volume change of the pressurizing chamber. Also good. In this case, the variable volume chamber and the fuel gallery are connected by the volume side passage.

  For example, when the volume change of the pressurizing chamber is “100”, it may be configured such that the volume change of the variable volume chamber is “60”. In this case, taking the metering process as an example, even if the fuel of “100” is returned from the pressurizing chamber to the fuel gallery, “60” of that is covered by the volume of the variable volume chamber. In this example, the damper member described above suppresses the change in the remaining "40" fuel pressure.

  In this way, the effect of suppressing the outflow of fuel to the inlet due to the change in the volume of the variable volume chamber can be obtained, so that the above-described effect stands out.

  From the standpoint of sufficiently functioning the damper member, as shown in claim 4, it is preferable that the flow changing portion generates a fuel flow toward the central portion of the movable portion of the diaphragm. If it does in this way, a diaphragm can fully be moved and a damper member can fully function.

  Specifically, as shown in claim 5, it is conceivable that the flow changing portion is formed as a concave portion on the inner surface of the lid portion. Further, in place of or in addition to such a configuration, as shown in claim 6, it is conceivable to form the convex portion on the inner surface of the lid portion. If the flow changing portion is formed as an uneven shape in this way, it is advantageous in that it can be formed relatively easily.

  In view of obtaining a further pulsation suppressing effect, as shown in claim 7, the lid side support portion that supports the damper member may be provided, and the lid side support portion may have a cylindrical wall. . The cylindrical wall surrounds the diaphragm in the circumferential direction to form a gallery partial space that opens toward the lid and has the diaphragm as an inner surface. In this case, there is a high possibility that the fuel guided to the diaphragm stays in the gallery subspace for a relatively long time, and the fuel flowing directly into the inlet can be reduced as much as possible. In addition, the diaphragm on the lid side can be sufficiently moved. In order to ensure such an action, it is preferable not to provide a through hole in the cylindrical wall. In this sense, as shown in claim 8, the cylindrical wall may form a gallery partial space that opens only to the lid side.

  In this way, when forming the gallery partial space with the lid-side support portion, in addition to or in place of the configuration in which the flow changing portion is provided as a concave portion or a convex portion on the inner surface of the lid portion, as shown in claim 9, the flow changing portion is It is good also as being formed as a part of cylindrical wall of a lid side support part. For example, as shown in claim 10, it is conceivable that the flow changing portion includes an umbrella-shaped roof portion that extends along the lid portion from the open end of the cylindrical wall and into which fuel flows inward. If it does in this way, since the fuel guide | induced to a diaphragm flows reliably into a gallery partial space by a flow change part, the fuel which flows directly into an inlet can be reduced as much as possible. In addition, the diaphragm on the lid side can be sufficiently moved.

  If such a cylindrical wall extends to the extension region, the flow of fuel toward the lid may be hindered. Therefore, as shown in claim 11, the edge of the cylindrical wall on the lid side may be inclined so as to suppress the overhang of the cylindrical wall into the extended region. If it does in this way, it can control that the flow of the fuel which goes to a lid part is inhibited.

  In addition, there is a possibility that corrosive substances such as liquid may accumulate on the outer surface of the lid part because the high pressure pump is usually installed so that the lid part is on the upper side in the vertical direction. Therefore, as shown in claim 12, the lid portion may have a corrosive burn portion that promotes the burn of corrosive matter on the outer surface thereof. In this way, accumulation of corrosives can be prevented. As a result, it is possible to prevent rust and the like from occurring.

It is sectional drawing which shows the structure of the high pressure pump of one Embodiment. It is a partial expanded sectional view which shows the characteristic part of the high pressure pump of one Embodiment. It is explanatory drawing which shows the shape of the cover part of a high pressure pump. It is explanatory drawing which shows the shape of the cover part of a high pressure pump. It is explanatory drawing which shows the shape of the cover part of a high pressure pump. It is explanatory drawing which shows the shape of the cover part of a high pressure pump. It is a partial expanded sectional view which shows the characteristic part of the high pressure pump of another embodiment. It is sectional drawing which shows the structure of the high pressure pump of another embodiment. It is sectional drawing which shows the structure of the high pressure pump of another embodiment. It is explanatory drawing which shows the shape of the cover part of a high pressure pump. It is sectional drawing which shows the structure of the high pressure pump of another embodiment. It is explanatory drawing which shows the shape of the cover side support part of a high pressure pump. It is explanatory drawing which shows the shape of the cover side support part of a high pressure pump.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. The high-pressure pump according to the present embodiment is used by being mounted on a vehicle, pressurizes the fuel pumped up from the fuel tank by the low-pressure pump and supplied from the inlet, and supplies it to the fuel rail to which the injector is connected. A pipe from a low pressure pump is connected to the upstream side of the inlet.

  As shown in FIG. 1, the high-pressure pump 1 includes a main body unit 10, a fuel supply unit 30, a suction valve unit 50, a plunger unit 70, and a discharge valve unit 90.

The main body 10 has a housing 11 that forms an outer shell. A fuel supply unit 30 is formed in a part of the housing 11 (upper part in FIG. 1).
Moreover, the plunger part 70 is provided in the exact opposite side (lower part in FIG. 1) of the fuel supply part 30. FIG. A pressurizing chamber 12 capable of pressurizing fuel is formed near the middle between the plunger unit 70 and the fuel supply unit 30.
Furthermore, an intake valve portion 50 (left side portion in FIG. 1) and a discharge valve portion 90 (right side portion in FIG. 1) are provided in a direction orthogonal to the arrangement direction of the fuel supply portion 30 and the plunger portion 70. .

  Next, the configuration of the fuel supply unit 30, the intake valve unit 50, the plunger unit 70, and the discharge valve unit 90 will be described in detail.

  The fuel supply unit 30 includes a fuel gallery 31. The fuel gallery 31 is a space surrounded by the concave portion 13 and the lid portion 14 of the housing 11. A damper unit 32 is disposed in the fuel gallery 31. The damper unit 32 includes a damper member 35 formed by joining two metal diaphragms 33, 34, a bottom side support portion 36 disposed on the bottom portion 15 of the recess 13, and a lid disposed on the lid portion 14 side. It is comprised with the side support part 37. FIG.

  The fuel gallery 31 has a recess 151 at the bottom 15 that matches the bottom support 36. Thereby, the bottom side support part 36 is positioned by this hollow 151. Further, as shown in FIG. 2, an inlet opening 19 is formed in the recess 151. As a result, the fuel from the low pressure pump is supplied to the radially inner region of the bottom support 36.

  A wave spring 38 is disposed above the lid side support portion 37. Thus, in a state where the lid portion 14 is attached to the housing 11, the wave spring 38 presses the lid side support portion 37 toward the bottom portion 15 side. As a result, the damper member 35 is sandwiched by the lid-side support portion 37 and the bottom-side support portion 36 with a uniform force in the circumferential direction.

Next, the plunger part 70 will be described.
As shown in FIG. 1, the plunger unit 70 includes a plunger 71, an oil seal holder 72, a spring seat 73, a plunger spring 74, and the like.

  The plunger 71 has a large-diameter portion 711 supported by a cylinder 16 formed inside the housing 11 and a small-diameter portion 712 having a smaller outer diameter than the large-diameter portion 711. The small diameter portion 712 is surrounded by the oil seal holder 72. The large diameter portion 711 and the small diameter portion 712 are integrated and reciprocate in the axial direction.

  The oil seal holder 72 is disposed at the end of the cylinder 16 and has a base 721 located on the outer periphery of the small diameter portion 712 of the plunger 71 and a press-fit portion 722 that is press-fitted into the housing 11.

  The base 721 has a ring-shaped seal 723 inside. The seal 723 includes an inner peripheral Teflon ring (“Teflon” is a registered trademark) and an outer peripheral O-ring. By this seal 723, the thickness of the fuel oil film around the small diameter portion 712 of the plunger 71 is adjusted, and fuel leakage to the engine is suppressed.

  In addition, the base 721 has an oil seal 725 at the tip. The oil seal 725 regulates the thickness of the oil film around the small diameter portion 712 of the plunger 71, thereby suppressing oil leakage.

  The press-fitting portion 722 is a portion that protrudes in a cylindrical shape around the base portion 721, and the cylindrical portion has a U-shaped longitudinal section. On the other hand, a recess 17 corresponding to the press-fit portion 722 is formed in the housing 11. As a result, the oil seal holder 72 is press-fitted in such a manner that the press-fitting portion 722 is pressed against the radially inner wall of the recess 17.

  The spring seat 73 is disposed at the end of the plunger 71. The end of the plunger 71 is in contact with a tappet (not shown). The tappet makes its outer surface contact a cam attached to a camshaft (not shown), and reciprocates in the axial direction according to the cam profile by the rotation of the camshaft. As a result, the plunger 71 reciprocates in the axial direction.

  One end of the plunger spring 74 is locked to the spring seat 73, and the other end is locked to the deep portion of the press-fit portion 722 of the oil seal holder 72. Thereby, the plunger spring 74 functions as a return spring of the plunger 71 and urges the plunger 71 to contact the tappet.

  With this configuration, the reciprocating movement of the plunger 71 according to the rotation of the camshaft is realized. At this time, a volume change of the pressurizing chamber 12 is created by the large diameter portion 711 of the plunger 71.

  In this embodiment, in particular, a variable volume chamber 75 is formed around the small diameter portion 712 of the plunger 71. Here, a region surrounded by the cylinder 16 of the housing 11 and the base end surface (step surface with the small diameter portion 712) of the large diameter portion 711 of the plunger 71, the outer peripheral wall of the small diameter portion 712, and the seal 723 of the oil seal holder 72. Is the variable volume chamber 75. Although the seal 723 suppresses fuel leakage as described above, the seal 723 seals the variable volume chamber 75 in a liquid-tight manner and prevents fuel leak from the variable volume chamber 75 to the engine.

  The variable volume chamber 75 includes a cylindrical cylindrical passage 727 formed between the press-fit portion 722 and the concave portion 17 in the radially inward direction, an annular annular passage 728 formed deep in the concave portion 17, and the housing 11. It is connected to the bottom 15 of the fuel gallery 31 via the formed volume-side passage 18 (passage indicated by a broken line in the figure).

Next, the suction valve unit 50 will be described.
As shown in FIG. 1, the suction valve unit 50 includes a cylinder part 51 formed by the housing 11, a valve part cover 52 that covers the opening of the cylinder part 51, a connector 53, and the like.
The cylindrical portion 51 is formed in a substantially cylindrical shape, and the inside is a fuel passage 55. A substantially cylindrical seat body 56 is disposed in the fuel passage 55. A suction valve 57 is disposed inside the seat body 56. Further, the fuel passage 55 communicates with the fuel gallery 31 via the pressure side passage 58.

  A needle 59 is in contact with the suction valve 57. The needle 59 passes through the valve cover 52 described above and extends to the inside of the connector 53. The connector 53 includes a coil 531 and a terminal 532 for energizing the coil 531. Inside the coil 531, a fixed core 533, a movable core 534, and a spring 535 interposed between the fixed core 533 and the movable core 534 are disposed. Here, the needle 59 described above is fixed to the movable core 534. That is, the movable core 534 and the needle 59 are integrated.

  With this configuration, when energization is performed via the terminal 532 of the connector 53, a magnetic attractive force is generated between the fixed core 533 and the movable core 534 by the magnetic flux generated in the coil 531. As a result, the movable core 534 moves to the fixed core 533 side, and accordingly, the needle 59 moves in a direction away from the pressurizing chamber 12. At this time, the movement of the suction valve 57 is not restricted by the needle 59. Therefore, the suction valve 57 can be seated on the seat body 56, and the fuel passage 55 and the pressurizing chamber 12 are blocked by the seating of the suction valve 57.

  On the other hand, if energization through the terminal 532 of the connector 53 is not performed, no magnetic attractive force is generated, so that the movable core 534 is moved toward the pressurizing chamber 12 by the spring 535. As a result, the needle 59 moves in a direction approaching the pressurizing chamber 12. As a result, the movement of the suction valve 57 is regulated by the needle 59, and the suction valve 57 is held on the pressurizing chamber 12 side. At this time, the intake valve 57 is separated from the seat body 56, and the fuel passage 55 and the pressurizing chamber 12 communicate with each other.

Next, the discharge valve unit 90 will be described.
As shown in FIG. 1, the discharge valve portion 90 has a cylindrical accommodating portion 91 formed by the housing 11. A discharge valve 92, a spring 93, and a locking portion 94 are accommodated in a storage chamber 911 formed by the storage portion 91. Further, the opening portion of the storage chamber 911 is a discharge port 95. A valve seat is formed in the deep portion of the storage chamber 911 opposite to the discharge port 95.

  The discharge valve 92 contacts the valve seat by the biasing force of the spring 93 and the pressure from the fuel rail (not shown). As a result, the discharge valve 92 stops discharging fuel while the fuel pressure in the pressurizing chamber 12 is low. On the other hand, when the pressure of the fuel in the pressurizing chamber 12 increases and overcomes the biasing force of the spring 93 and the pressure from the fuel rail side, the discharge valve 92 moves toward the discharge port 95. As a result, the fuel that has flowed into the storage chamber 911 is discharged from the discharge port 95.

  Here, particularly in the present embodiment, as shown in FIG. 2, the extension region (indicated by symbol R) of the pressure side passage 58 where the flow of fuel returned from the pressurizing chamber 12 to the fuel gallery 31 by the plunger 71 can be relatively fast. (Hereinafter referred to as “extended region R”) is assumed inside the fuel gallery 31, and the extended region R extends toward the lid portion 14.

  Specifically, as shown in FIG. 2, the pressurizing side passage 58 opens to the side wall 311 of the fuel gallery 31. At this time, the pressurizing side passage 58 is provided so as to be inclined with respect to the pressing direction (direction indicated by symbol D in FIG. 2) by the lid portion 14 so that the extension region R of the pressurizing side passage 58 extends toward the lid portion 14. It has been.

  In particular, in this embodiment, a flow changing portion 14a as shown in FIG. The flow changing portion 14 a is formed by pressing as a concave portion on the inner surface of the lid portion 14. However, it may be processed by other methods such as casting.

  FIG. 3A is an explanatory diagram schematically showing the lid portion 14, where the upper stage is a plan view and the lower stage is a cross-sectional view taken along the line d 1 -d 1. Here, as shown in FIG. 3A, the flow changing portion 14a is a concave portion having a semicircular shape in plan view, and becomes deeper toward the central portion. Thereby, the fuel collision wall 14b is formed along the pressing direction of the lid portion 14 (the direction indicated by the symbol D in FIG. 2). Moreover, the upper surface of the cover part 14 becomes convex shape, and becomes the water draining part 14c.

  Furthermore, particularly in the present embodiment, as shown in FIG. 2, the bottom support 36 has a bottom cylindrical wall 39 that surrounds the diaphragm 33 on the bottom 15 side in the circumferential direction. A through-hole 391 is formed in the bottom cylindrical wall 39 in the circumferential direction. On the other hand, the lid-side support portion 37 has a lid-side cylindrical wall 40 that surrounds the diaphragm 34 on the lid portion 14 side in the circumferential direction. The lid-side cylindrical wall 40 is not provided with a through hole 391 unlike the bottom-side cylindrical wall 39. Thus, the lid-side cylindrical wall 40 forms a gallery partial space 41 that has the diaphragm 34 on the lid 14 side as an inner surface and opens only to the lid 14 side.

Next, the operation of the high-pressure pump 1 will be described.
The high-pressure pump 1 shown in FIG. 1 operates by repeating the suction stroke, the metering stroke, and the pressurization stroke.
The suction stroke is a stroke for sucking fuel from the fuel gallery 31 into the pressurizing chamber 12. At this time, the plunger 71 moves from the top dead center to the bottom dead center, and the suction valve 57 is in the open state.

  The metering process is a process of returning fuel from the pressurizing chamber 12 to the fuel gallery 31. At this time, the plunger 71 moves from the bottom dead center to the top dead center, and the suction valve 57 is in an open state. Therefore, the fuel returning from the pressurizing chamber 12 to the fuel gallery 31 in the metering step is a low-pressure fuel. This metering method is called so-called prestroke metering.

  The pressurization stroke is a stroke in which fuel is discharged from the pressurization chamber 12 via the discharge valve portion 90. At this time, the plunger 71 moves toward the top dead center, and the suction valve 57 is closed.

Here, the function of the variable volume chamber 75 will be described.
In the suction stroke, the volume of the pressurizing chamber 12 increases due to the movement of the plunger 71. On the other hand, the volume of the variable volume chamber 75 decreases. Therefore, the fuel stored in the variable volume chamber 75 is supplied to the fuel gallery 31.

  In the metering stroke, the volume of the pressurizing chamber 12 decreases due to the movement of the plunger 71. On the other hand, the volume of the variable volume chamber 75 increases. Accordingly, a part of the fuel returned from the pressurizing chamber 12 to the fuel gallery 31 is sent to the variable volume chamber 75.

Here, the volume change of the variable volume chamber 75 is caused by the large-diameter portion 711 of the plunger 71 as in the pressurizing chamber 12. In other words, the volume change of the pressurizing chamber 12 and the volume change of the variable volume chamber 75 have the same rate of volume change and are in the same phase.
In the pressurization stroke, since the intake valve 57 is closed, the return of fuel from the pressurization chamber 12 to the fuel gallery 31 is not a problem.

Next, the effect which the high pressure pump 1 of this form exhibits is demonstrated.
In the high-pressure pump 1 of this embodiment, as shown in FIG. 2, most of the fast-flowing fuel is guided to the lid portion 14 by the extension region R. In other words, the main flow of fuel when the flow becomes faster is guided to the lid portion 14. The fuel guided to the lid portion 14 travels along the inner surface of the lid portion 14, collides with the fuel collision wall 14 b of the flow changing portion 14 a, changes direction, and then the lid portion 14 side constituting the damper member 35. It collides with the central portion of the diaphragm 34 (see the two-dot chain arrow S in FIG. 2).

  As a result, most of the fuel passes through the lid portion 14, so that the fuel that flows directly into the opening 19 of the inlet can be reduced as much as possible. Further, the diaphragm 34 on the lid portion 14 side can be sufficiently moved, and the damper member 35 can sufficiently function. As a result, pulsation can be sufficiently suppressed, for example, when the flow of fuel returned to the fuel gallery 31 becomes faster.

  Moreover, in the high-pressure pump 1 of the present embodiment, a flow of fuel toward the central portion of the movable portion of the diaphragm 34 is created by the flow changing portion 14a. Thereby, the diaphragm 34 can be moved sufficiently and the damper member 35 can fully function.

  In the high-pressure pump 1 of this embodiment, a part of the fuel returned to the fuel gallery 31 is covered by the variable volume chamber 75 (see FIG. 1). Therefore, pulsation can be sufficiently suppressed, for example, when the flow of fuel returned to the fuel gallery 31 becomes faster.

  In addition, as described above, the volume change of the pressurizing chamber 12 and the volume change of the variable volume chamber 75 occur in the same phase, so that an effect is always obtained regardless of the engine speed and the cam profile. Further, the small diameter portion 712 is provided in the plunger 71 so as to form the variable volume chamber 75. However, when the small diameter portion 712 is sealed with the seal 723 and the oil seal 725, the circumference is longer than when the large diameter portion is sealed. As a result, the effective sealing is realized. As the diameter of the seal portion is reduced, the diameter of the oil seal holder 72 holding the seal can be reduced. Therefore, the plunger spring 74 can be reduced in diameter, and as a result, the high-pressure pump 1 can be reduced in size. Greatly contributes to Furthermore, if the diameter of the small diameter portion 712 is kept as it is and the diameter of the large diameter portion 711 is increased, the discharge amount can be increased. In this case, basically, it is only necessary to design the large-diameter portion 711 and the cylinder 16 on which the large-diameter portion 711 slides, and the discharge amount can be increased by a simple design change.

  Furthermore, in the high-pressure pump 1 of this embodiment, the flow changing portion 14 a is formed as a concave portion on the inner surface of the lid portion 14. Thereby, formation of the flow change part 14a also becomes comparatively easy.

  Further, in the high-pressure pump 1 of the present embodiment, the lid side support portion 37 has a lid side cylindrical wall 40 that surrounds the diaphragm 34 on the lid portion 14 side in the circumferential direction. A through hole 391 such as the bottom cylindrical wall 39 is not provided. Thus, the lid-side cylindrical wall 40 forms a gallery partial space 41 that has the diaphragm 34 on the lid 14 side as an inner surface and opens only to the lid 14 side. As a result, there is a high possibility that the fuel guided to the lid portion 14 side of the damper unit 32 stays in the gallery partial space 41 for a relatively long time, and the fuel flowing directly into the inlet opening 19 can be reduced as much as possible. Further, the diaphragm 34 on the lid 14 side can be sufficiently moved.

  Furthermore, in the high-pressure pump 1 of the present embodiment, since the water draining portion 14c is formed on the upper surface of the lid portion 14, it is possible to prevent accumulation of corrosive substances such as rainwater. As a result, it is possible to prevent rust and the like from occurring.

  The opening 19 in this embodiment constitutes the “fuel inlet opening” described in “Claims”, the fuel gallery 31 constitutes “the fuel gallery”, and the pressurizing chamber 12 is the “pressurizing chamber”. And the pressurizing side passage 58 constitutes a “pressurizing side passage”.

  The plunger 71 constitutes a “plunger”, the large diameter portion 711 constitutes a “large diameter portion”, the small diameter portion 712 constitutes a “small diameter portion”, and the variable volume chamber 75 constitutes a “variable volume chamber”. The volume side passage 18 constitutes the “volume side passage”.

  Furthermore, the diaphragms 33 and 34 constitute a “diaphragm”, the damper member 35 constitutes a “damper member”, and the lid side support portion 37 constitutes a “lid side support portion”. Further, the lid-side cylindrical wall 40 of the lid-side support portion 37 constitutes a “cylindrical wall”, the lid portion 14 constitutes a “lid portion”, and the extension region R constitutes an “extension region”.

  Further, the flow changing portion 14a which is a concave portion on the inner surface of the lid portion 14 constitutes a “flow changing portion”, and the water draining portion 14c on the outer surface constitutes a “liquid burning portion”.

As mentioned above, this invention is not limited to the said form at all, In the range which does not deviate from the meaning, it can implement with a various form.
(A) In the above embodiment, the flow changing portion 14a having a semicircular shape in plan view as shown in FIG. 3A is formed in the lid portion 14, but various flow changing portions as shown below may be formed. . Here, description will be made by appropriately using the reference numerals of the above embodiments.

  FIG. 3B is an explanatory diagram schematically showing the lid 140, in which the upper part is a plan view and the lower part is a cross-sectional view taken along line d2-d2. Here, as shown in FIG. 3B, the flow changing portion 140a is a concave portion that becomes deeper from the edge toward the central portion, as in FIG. 3A. However, unlike FIG. 3A, the width becomes narrower toward the center portion, and the fuel collision wall 140b is formed. By doing so, the flow of the fuel flowing along the flow changing portion 140a becomes faster, and the fuel having a faster flow collides with the fuel collision wall 140b. As a result, a fast fuel flow toward the diaphragm 34 can be created, and the damper member 35 can function sufficiently. Moreover, the upper surface of the cover part 140 is a convex watering part 140c. Thereby, accumulation of corrosive substances such as rainwater can be prevented. As a result, it is possible to prevent rust and the like from occurring.

  FIG. 4A is an explanatory diagram schematically showing the lid 141, where the upper part is a plan view and the lower part is a cross-sectional view taken along line d3-d3. Here, the flow changer 141a is formed as a recess on the inner surface of the lid 141 as shown in FIG. In this case, it is press-worked so that the central portion protrudes inward in a straight line with respect to the concave portion having a circular shape when viewed from above. Thereby, the fuel collision wall 141b is formed by the protruding portion. Also in this case, a fuel flow toward the diaphragm 34 can be created, and the damper member 35 can function sufficiently. Moreover, the upper surface of the cover part 141 is the water draining part 141c. In particular, since a linear recess is formed (see symbol A), corrosives such as rainwater fall through this recess. Thereby, it can prevent that corrosive liquid substances, such as rain water, accumulate. As a result, it is possible to prevent rust and the like from occurring.

  FIG. 4B is an explanatory diagram schematically showing the lid 142, with the upper part being a plan view and the lower part being a sectional view taken along the line d4-d4. Here, the flow change part 142a is formed as a recessed part of the inner surface of the cover part 141 similarly to Fig.4 (a). In this case, the central portion of the concave portion having a circular shape when viewed from above is pressed so as to protrude inward in a cross shape. Thereby, the fuel collision wall 142b is formed by the protruding portion. Also in this case, a fuel flow toward the diaphragm 34 can be created, and the damper member 35 can function sufficiently. Further, the upper surface of the lid portion 142 is a water draining portion 142c. In particular, since a concave portion having a cross shape in plan view is formed (see symbol B), corrosive substances such as rainwater fall through the concave portion. Thereby, accumulation of corrosive substances such as rainwater can be prevented. As a result, it is possible to prevent rust and the like from occurring.

  FIG. 5A is an explanatory diagram schematically showing the lid 143, in which the upper part is a plan view and the lower part is a cross-sectional view taken along line d5-d5. Here, the flow changing portion 143 a is formed as a convex portion on the inner surface of the lid portion 143. In this case, it is press-worked so as to form a linear convex portion on the inner surface of the lid portion 143. Thereby, the fuel collision wall 143b is formed by the convex portion. Also in this case, a fuel flow toward the diaphragm 34 can be created, and the damper member 35 can function sufficiently.

  FIG. 5B is an explanatory diagram schematically showing the lid 144, with the upper part being a plan view and the lower part being a sectional view taken along the line d6-d6. Here, the flow changing portion 144 a is formed as a convex portion on the inner surface of the lid portion 144. In this case, it is press-worked so as to form a convex portion protruding in a cross shape on the inner surface of the lid portion 144. Thus, the fuel collision wall 144b is formed by the cross-shaped convex portion. Also in this case, a fuel flow toward the diaphragm 34 can be created, and the damper member 35 can function sufficiently.

  FIG. 6A is an explanatory diagram schematically showing the lid portion 145, in which the upper stage is a plan view and the lower stage is a sectional view taken along line d7-d7. Here, as shown in FIG. 6A, the flow changing portion 145a is a concave portion that becomes deeper from the edge toward the central portion, as in FIG. 3A. However, unlike FIG. 3A, a recess is formed to a position beyond the central portion, and a fuel collision wall 145b is formed at a position away from the central portion. Also in this case, if the fuel is guided to the movable part of the diaphragm 34, the damper member 35 can function sufficiently. Moreover, the upper surface of the cover part 145 is a convex watering part 145c. Thereby, accumulation of corrosive substances such as rainwater can be prevented. As a result, it is possible to prevent rust and the like from occurring.

  FIG. 6B is an explanatory diagram schematically showing the lid 146, in which the upper part is a plan view and the lower part is a sectional view taken along line d8-d8. Here, as shown in FIG. 6B, the flow changing portion 146a is formed by combining a concave portion and a convex portion. Specifically, it is composed of a concave portion (see symbol C) that becomes deeper toward the central portion and a linear convex portion (see symbol D) that protrudes inward from the central portion. And the connection part of a recessed part and a convex part is the fuel collision wall 146b. In this way, since the fuel is reliably guided to the central portion of the movable portion of the diaphragm 34, the damper member 35 can function sufficiently.

  (B) A damper unit 42 as shown in FIG. In the damper unit 42, the configuration of the lid-side support portion 43 is different from that in the above embodiment. Specifically, the edge portion of the lid-side cylindrical wall 44 that surrounds the diaphragm 34 on the lid portion 14 side in the circumferential direction is formed so as not to protrude into the extension region R. It has become. Thereby, it can suppress that the flow of the fuel which goes to the cover part 14 is inhibited.

  (C) In the above embodiment, the pressurizing side passage 58 is provided to be inclined, but on the other hand, it is formed along the pressing direction of the damper unit 32 from the fuel passage 55 (the direction indicated by symbol D in FIG. 2). The pressure side passage may be provided so as to be bent in the middle toward the fuel gallery 31 and to be opened at a position close to the lid portion 14 of the fuel gallery 31.

  (D) It is also conceivable to open the pressure side passage at the bottom of the fuel gallery. Specifically, as shown in FIG. 8, the fuel gallery 31 is opened at the bottom 15. Here, it is exemplified that the pressure side passage 581 is provided on the outer peripheral side of the bottom cylindrical wall 39. In this case, an annular member 582 is disposed around the wave spring 38 to create a flow along the lid portion 14. The annular member 582 has an inner peripheral surface that is a tapered surface, and the inner diameter becomes smaller toward the lid portion 14. Even if it does in this way, the same effect as the above-mentioned form is produced.

(E) When the pressure side passage is provided as shown in (d) above, it is conceivable to employ, for example, a lid 147 as shown in FIG. FIG. 9 differs from FIG. 8 only in the structure of the lid 147.
FIG. 10 is an explanatory view schematically showing the lid 147, with the upper part being a plan view and the lower part being a cross-sectional view taken along line d9-d9. Here, as shown in FIG. 10, the flow changing portion 147 a is different from FIG. 3A in that the edge is deeper and an inclined fuel collision wall 147 b is formed. In this way, a flow along the lid 147 can be created without employing the annular member 582 as shown in FIG. 8, and the damper member 35 can function sufficiently. Moreover, the upper surface of the cover part 145 is a convex watering part 147c. Thereby, accumulation of corrosive substances such as rainwater can be prevented. As a result, it is possible to prevent rust and the like from occurring.

(F) In the above embodiment, the flow changing portion 14a is formed in the lid portion 14. On the other hand, as shown in FIG. 11, the flow changing portion 401 a may be formed as a part of the lid-side cylindrical wall 401 of the lid-side support portion 371 constituting the damper unit 321.
Specifically, as shown in FIG. 12, the lid portion 148 has a shape that bulges outward from the center portion, and the shape of the lid-side support portion 371 of the damper unit 321 is different. In this case, a part of the opening end of the lid-side cylindrical wall 401 located on the radially inner side of the wave spring 38 extends toward the lid portion 148 to form a roof portion 401b that covers the diaphragm 34 on the lid portion 148 side. Yes. The roof portion 401 b has a substantially semicircular shape when viewed from above, and is formed in a portion far from the pressure side passage 58.

  With this configuration, as shown in FIG. 12, most of the fast-flowing fuel is guided to the lid 148 by the extension region R. In other words, the main flow of fuel when the flow becomes faster is guided to the lid 148. The fuel guided to the lid portion 148 travels along the inner surface of the lid portion 148, flows into the inside of the roof portion 401b of the flow changing portion 401a, changes direction, and then the lid portion 148 side constituting the damper member 35 (Refer to a two-dot chain line T).

  As a result, most of the fuel passes through the lid portion 148, so that the fuel that flows directly into the opening 19 of the inlet can be reduced as much as possible. In addition, the diaphragm 34 on the lid 148 side can be sufficiently moved, and the damper member 35 can function sufficiently. As a result, pulsation can be sufficiently suppressed when the flow of fuel returned to the fuel gallery 31 becomes faster. In addition, the fuel guided to the lid 148 side of the damper unit 321 is likely to stay in the gallery partial space 41 for a relatively long time, and the fuel that flows directly into the inlet opening 19 can be reduced as much as possible. As a result, the diaphragm 34 on the lid 148 side can be sufficiently moved.

  In this case, the diaphragms 33 and 34 constitute a “diaphragm”, the damper member 35 constitutes a “damper member”, and the lid side support portion 371 constitutes a “lid side support portion”. Further, the lid-side cylindrical wall 401 of the lid-side support portion 371 constitutes a “tubular wall”, the flow changing portion 401a constitutes a “flow changing portion”, and the roof portion 401b constitutes a “roof portion”. The lid portion 148 constitutes a “lid portion”, and the extension region R constitutes an “extension region”.

(G) Instead of the lid side support portion 371 described in (f) above, a lid side support portion 372 as shown in FIG. 13 may be adopted.
In FIG. 13, the roof portion 402 b of the flow changing portion 402 a is provided corresponding to the substantially central portion of the lid portion 148, and a fuel collision wall 402 c extending from the roof portion 402 b toward the damper member 35 is provided. .

  With this configuration, as shown in FIG. 13, the fuel guided to the lid portion 148 by the extension region R travels along the inner surface of the lid portion 148 and flows into the inside of the roof portion 402b of the flow changing portion 402a. The direction changes by colliding with the collision wall 402c, and then collides with the central portion of the diaphragm 34 on the lid 148 side constituting the damper member 35 (see the two-dot chain line U).

  As a result, the same effect as described in (F) above is achieved. In addition, the fuel collision wall 402c of the flow changing portion 402a creates a fuel flow toward the central portion of the movable portion of the diaphragm 34 on the lid portion 148 side. Therefore, the diaphragm 34 can be sufficiently moved, and the damper member 35 Can fully function.

  In this case, the diaphragms 33 and 34 constitute a “diaphragm”, the damper member 35 constitutes a “damper member”, and the lid side support portion 372 constitutes a “lid side support portion”. Further, the lid-side cylindrical wall 402 of the lid-side support portion 372 constitutes a “tubular wall”, the flow changing portion 402a constitutes a “flow changing portion”, and the roof portion 402b constitutes a “roof portion”. The lid portion 148 constitutes a “lid portion”, and the extension region R constitutes an “extension region”.

  1: high pressure pump, 10: main body, 11: housing, 12: pressurizing chamber, 13: recess, 14: lid, 14a: flow changer, 14b: fuel collision wall, 14c: drainage, 15: bottom, 151: depression, 16: cylinder, 17: recess, 18: volume side passage, 19: opening, 30: fuel supply part, 31: fuel gallery, 311: side wall, 32, 42: damper unit, 321: bottom edge Part, 33, 34: diaphragm, 35: damper member, 36: bottom side support part, 37, 43: cover side support part, 38: spring washer, 39: bottom cylindrical wall, 391: through hole, 40, 44 : Cover side cylindrical wall, 41: gallery partial space, 45: inclined part, 50: suction valve part, 51: cylinder part, 52: valve part cover, 53: connector, 531: coil, 532: terminal, 533: fixed Core 534: movable core, 5 5: Spring, 55: Fuel passage, 56: Seat body, 57: Suction valve, 58, 581: Pressure side passage, 582: Annular member, 59: Needle, 70: Plunger part, 71: Plunger, 711: Large diameter part 712: Small diameter portion 72: Oil seal holder 721: Base portion 722: Press fit portion 723: Seal 725: Oil seal 727: Cylindrical passage 728: Annular passage 73: Spring seat 74: Plunger spring 75: Variable volume chamber, 90: Discharge valve portion, 91: Storage portion, 911: Storage chamber, 92: Discharge valve, 93: Spring, 94: Locking portion, 95: Discharge port, 140, 141, 142, 143 144, 145, 146, 147, 148: lid, 140a, 141a, 142a, 143a, 144a, 145a, 146a, 147a: flow Further part, 140b, 141b, 142b, 143b, 144b, 145b, 146b, 147b: fuel collision wall, 140c, 141c, 142c, 145c, 147c: drainage part, 321, 322: damper unit, 371, 372: cover side support Part, 401, 402: lid side cylindrical wall, 401a, 402a: flow changing part, 401b, 402b: roof part, 402c: fuel collision wall

Claims (12)

A pressurizing side passage connecting a fuel gallery having a fuel inlet opening for supplying fuel to a pressurizing chamber in which the fuel is pressurized;
A plunger for creating a volume change of the pressurizing chamber;
A damper member disposed in the fuel gallery and configured by a diaphragm to suppress a change in fuel pressure inside the fuel gallery;
A lid part assembled at a predetermined position of the housing to form the fuel gallery;
With
The pressure side passage and the lid are arranged so that a fuel flow along the lid is created by the flow of fuel returned by the plunger from the pressure side passage to the fuel gallery;
A high-pressure pump, comprising: a flow changing portion that creates a flow of fuel toward the movable portion of the diaphragm of the damper member. The high-pressure pump according to claim 1,
The high-pressure pump, wherein an extension region of the pressurization side passage that can accelerate the flow of fuel returned from the plunger to the fuel gallery from the pressurization side passage extends toward the lid. The high-pressure pump according to claim 1 or 2,
The plunger changes the volume of the pressurizing chamber and forms a variable volume chamber that changes in volume with a change in volume of the pressurizing chamber,
The high-pressure pump further includes a volume side passage connecting the variable volume chamber to the fuel gallery. In the high pressure pump according to any one of claims 1 to 3,
The high-pressure pump, wherein the flow changing unit creates a fuel flow toward a central portion of the movable portion of the diaphragm. In the high pressure pump according to any one of claims 1 to 4,
The high pressure pump, wherein the flow changing portion is formed as a concave portion on an inner surface of the lid portion. In the high-pressure pump according to any one of claims 1 to 5,
The high-pressure pump, wherein the flow changing portion is formed as a convex portion on the inner surface of the lid portion. In the high pressure pump according to any one of claims 2 to 6,
Surrounding the diaphragm in the circumferential direction has a cylindrical wall having the diaphragm as an inner surface and forming a gallery partial space that opens to the lid portion side, and includes a lid-side support portion that supports the damper member. High pressure pump characterized by The high-pressure pump according to claim 7,
The said cylindrical wall forms the gallery partial space opened only to the cover part side. The high pressure pump characterized by the above-mentioned. The high-pressure pump according to claim 7 or 8,
The high-pressure pump, wherein the flow changing portion is formed as a part of a cylindrical wall of the lid-side support portion. The high-pressure pump according to claim 9,
The high-pressure pump characterized in that the flow changing portion includes an umbrella-shaped roof portion that extends from the end portion of the cylindrical wall along the lid portion and into which fuel flows inward. In the high pressure pump according to any one of claims 7 to 10,
The high-pressure pump characterized in that the cylindrical wall has an inclined edge on the lid side so as to suppress overhanging into the extension region. In the high pressure pump according to any one of claims 1 to 11,
The high-pressure pump characterized in that the lid portion has a corrosive-burning portion that promotes the burning of the corrosive material on the outer surface thereof.

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