JP2010190107A - High-pressure pump - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a high-pressure pump efficiently sucking fuel in a suction stroke. <P>SOLUTION: A supply passage 133 connects an inlet to the supply port 132 of a fuel gallery 13. A suction passage is connected to the suction opening 135 of the fuel gallery 13. At this time, in the fuel gallery 13 formed into a circular shaped in a planar view, the supply port 132 and suction opening 135 are formed in the diametrical direction passing through a center O. In this case, a virtual vector V1 in a suction direction directed from the center O to the suction opening 135 and a virtual vector V2 in a supply direction directed from the supply port 132 to the center O are directed to the same direction. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

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

  A fuel supply device that supplies fuel to an engine includes a high-pressure pump that pumps high-pressure fuel. Generally, a high-pressure pump includes a plunger that reciprocates by the rotation of a camshaft.

  Specifically, the operation stroke of such a high-pressure pump is the intake stroke in which fuel is sucked from the fuel gallery in the pump into the pressurizing chamber when the plunger moves from the top dead center to the bottom dead center. The metering process to return some low-pressure fuel to the fuel gallery when going from the top dead center to the top dead center, and the pressurization stroke where the fuel is pressurized by the plunger going to the top dead center after closing the intake valve (For example, refer to Patent Document 1).

JP 2006-207486 A

  By the way, in recent years, the output of the engine has improved more and more, and the engine speed tends to increase. As the engine speed increases and the camshaft speed increases, the plunger reciprocates at high speed. Under such circumstances, it becomes important how efficiently the fuel is sucked in the suction stroke.

  In this regard, no consideration is given in the above-mentioned Patent Document 1, and there is a concern that the fuel intake efficiency in the intake stroke is reduced under a special situation where the plunger reciprocates at a high speed.

  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 efficiently sucking fuel in an intake stroke.

  In the high-pressure pump according to claim 1, which is made to achieve the above object, the supply passage connects from the inlet to the supply port of the fuel gallery. Therefore, when fuel is supplied from the inlet, the fuel is guided to the fuel gallery via the supply passage. A suction passage connects the suction port of the fuel gallery to the pressurizing chamber. Therefore, the fuel supplied to the fuel gallery is guided to the pressurizing chamber via the suction passage. The volume change of the pressurizing chamber is created by the plunger, and the pressurized fuel is discharged from the outlet.

  Here, in particular, the suction port is provided at the end of the fuel gallery in accordance with the first flow direction among a plurality of flow directions in which the fuel easily flows in the fuel gallery. The supply port is provided at the end of the fuel gallery in accordance with the second flow direction among the plurality of flow directions.

  The “flow direction”, which is the direction in which fuel easily flows, depends on the internal shape of the fuel gallery. For example, as shown in claim 3, the flow direction may be a direction in which the distance between the inner walls of the fuel gallery is relatively large. Further, for example, as shown in claim 4, on the assumption that the inside of the fuel gallery is a space having a circular shape in a plan view, the flow direction is a diametrical direction considered as a space having a circular shape in a plan view. Also good.

  In the present invention, the suction port is provided at the end of the fuel gallery in accordance with the first flow direction among the plurality of flow directions, and the supply port is provided at the end of the fuel gallery in accordance with the second flow direction. The “end portion” here includes the end of the fuel gallery and its periphery. The angle formed between the first virtual vector in the suction direction along the first flow direction and the second virtual vector in the supply direction along the second flow direction is an acute angle or a right angle.

  For example, assuming that the inside of the fuel gallery is a space having a circular shape in plan view, the flow direction is a diametrical direction, in which case the first virtual vector of the suction direction from the center toward the suction port, That is, the angle formed by the second virtual vector in the supply direction from the supply port toward the center is an acute angle.

In this way, the fuel can be smoothly guided from the supply port to the suction port, and the fuel can be efficiently sucked in the suction stroke.
Here, the technical idea is expressed as that the angle formed by the virtual vector is “acute angle or right angle”, but as shown in claim 2, “the first virtual vector in the suction direction along the first flow direction and The inner product of the second virtual vector in the supply direction along the second flow direction may be “0” or more.

  Further, from the viewpoint of efficiently inhaling fuel, as shown in claim 5, it is conceivable that the first virtual vector and the second virtual vector are in the same direction. For example, a supply port and an intake port are provided at the end of the fuel gallery along a predetermined flow direction so as to face each other. In this way, the fuel can be smoothly guided from the supply port to the suction port, and the fuel can be sucked efficiently in the suction stroke.

It is sectional drawing which shows the structure of the high pressure pump of embodiment of this invention. It is a schematic diagram which shows the structure of a fuel gallery.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. The high-pressure pump of the present embodiment is used by being mounted on a vehicle, and pressurizes the fuel pumped up from the fuel tank by the low-pressure pump and discharges it to the fuel rail.
As shown in FIG. 1, the high-pressure pump 1 includes a housing 10, a plunger portion 30, a suction valve portion 50, and a discharge valve portion 70 that constitute an outer shell.

  The housing 10 constitutes an outer shell. A cover 12 is attached in one direction (upward in FIG. 1) of the housing 10, and a space surrounded by the cover 12 and the housing 10 is a fuel gallery 13. The fuel gallery 13 has a pulsation damper 131 therein. The pulsation damper 131 is disposed with its end portions sandwiched therebetween.

  Connecting the inlet 11 to the supply port 132 of the fuel gallery 13 is a supply passage 133. Thereby, the fuel supplied from the inlet 11 is guided to the fuel gallery 13 via the supply passage 133. The suction passage 134 is connected to the suction port 135 of the fuel gallery 13. As a result, the fuel supplied to the fuel gallery 13 is guided to the pressurizing chamber 14 via the suction port 135. A pipe from a low pressure pump is connected to the upstream side of the inlet 11.

Further, the plunger portion 30 is provided on the opposite side of the cover 12 (downward in FIG. 1). A pressurizing chamber 14 capable of pressurizing fuel is formed near the middle between the plunger portion 30 and the fuel gallery 13.
Furthermore, an intake valve portion 50 (left side in FIG. 1) and a discharge valve portion 70 (right side in FIG. 1) are provided in a direction orthogonal to the arrangement direction of the cover 12 and the plunger portion 30.
With such a configuration, the fuel supplied to the fuel gallery 13 is discharged from the discharge valve portion 70 via the suction valve portion 50 and the pressurizing chamber 14.

Next, the structure of the plunger part 30, the suction valve part 50, and the discharge valve part 70 is demonstrated in detail.
First, the plunger unit 30 will be described.
The plunger unit 30 includes a plunger 31, an oil seal holder 32, a spring seat 33, a plunger spring 34, and the like.

  The plunger 31 has a large-diameter portion 311 supported by a cylinder 15 formed inside the housing 10 and a small-diameter portion 312 having a smaller diameter than the large-diameter portion 311 surrounded by the oil seal holder 32. The large diameter portion 311 and the small diameter portion 312 are integrated and reciprocate in the axial direction in the same phase.

  The oil seal holder 32 is disposed at the end of the cylinder 15. The oil seal holder 32 has a ring-shaped seal 323 therein. The seal 323 adjusts the thickness of the fuel oil film around the small-diameter portion 312 of the plunger 31 and suppresses fuel leakage to the engine. Further, the oil seal holder 32 has an oil seal 325 at the tip portion thereof. The oil seal 325 regulates the thickness of the oil film around the small diameter portion 312 of the plunger 31 and suppresses oil leakage.

  The spring seat 33 is disposed at the end of the plunger 31. The end of the plunger 31 abuts a lifter (not shown), and the lifter abuts the outer surface of the cam attached to the camshaft. Accordingly, the lifter reciprocates in the axial direction according to the cam profile by the rotation of the camshaft. As a result, the spring seat 33 reciprocates in the axial direction together with the plunger 31.

  The plunger spring 34 has one end locked to the spring seat 33 and the other end locked to the oil seal holder 32. Thereby, the plunger spring 34 functions as a return spring of the plunger 31 via the spring seat 33 and urges the plunger 31 to contact the lifter.

  With this configuration, the reciprocating movement of the plunger 31 according to the rotation of the camshaft is realized. At this time, the volume change of the pressurizing chamber 14 is created by the large diameter portion 311 of the plunger 31.

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 10, a valve part cover 52 that covers the opening of the cylinder part 51, a connector 53, and the like.
The cylinder part 51 is formed in a substantially cylindrical shape and has a fuel passage 55 inside. A substantially cylindrical seat body 56 is disposed in the fuel passage 55. A suction valve 57 is disposed inside the seat body 56. A spring 58 is accommodated in the intake valve 57.

  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 toward the fixed core 533, and accordingly, the needle 59 moves away from the pressurizing chamber 14. At this time, the movement of the suction valve 57 is not restricted by the needle 59. Accordingly, the intake valve 57 can be seated on the seat body 56, and the fuel passage 55 and the pressurizing chamber 14 are blocked by the seating of the intake valve 57.

  On the other hand, if energization is not performed via the terminal 532 of the connector 53, no magnetic attractive force is generated, so that the movable core 534 moves in a direction approaching the pressurizing chamber 14 by the spring 535. Thereby, the needle 59 moves to the pressurizing chamber 14 side. 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 14 side. At this time, the intake valve 57 is separated from the seat body 56, and the fuel passage 55 and the pressurizing chamber 14 communicate with each other.

Next, the discharge valve unit 70 will be described.
As shown in FIG. 1, the discharge valve unit 70 has a cylindrical outlet 71 formed in the housing 10. A discharge valve 72, a spring 73, and a locking portion 74 are accommodated in a storage chamber 711 formed by the outlet 71. Further, the opening portion of the storage chamber 711 is a discharge port 75. A valve seat 712 is formed in a deep portion of the storage chamber 711 on the opposite side to the discharge port 75.

  The discharge valve 72 abuts on the valve seat 712 by the biasing force of the spring 73 and the pressure from the fuel rail (not shown). Thereby, the discharge valve 72 stops the fuel discharge while the pressure of the fuel in the pressurizing chamber 14 is low. On the other hand, when the pressure of the fuel in the pressurizing chamber 14 increases and overcomes the urging force of the spring 73 and the pressure from the fuel rail side, the discharge valve 72 moves toward the discharge port 75. Thereby, the fuel that has flowed into the storage chamber 711 is discharged from the discharge port 75.

  Next, the configuration of the fuel gallery 13 will be described in detail. FIG. 2 is an explanatory diagram schematically showing a cross section taken along line II-II in FIG. In FIG. 2, the portion of the fuel gallery 13 is mainly shown.

  As shown in FIG. 2, the fuel gallery 13 has a circular shape in plan view, and the supply port 132 and the suction port 135 described above are formed in the diameter direction passing through the center O. In this case, the virtual vector V1 in the suction direction from the center O toward the suction port 135 and the virtual vector V2 in the supply direction from the supply port 132 toward the center O are in the same direction.

Next, the operation of the high-pressure pump 1 will be described. The high-pressure pump 1 operates by repeating an intake stroke, a metering stroke, and a pressurization stroke.
The suction stroke is a stroke for sucking fuel from the fuel gallery 13 into the pressurizing chamber 14. At this time, the plunger 31 moves from the top dead center toward the bottom dead center (moves away from the pressurizing chamber 14), and the suction valve 57 is in the open state. The metering process is a process of returning low-pressure fuel from the pressurizing chamber 14 to the fuel gallery 13. At this time, the plunger 31 moves from the bottom dead center toward the top dead center (moves in a direction approaching the pressurizing chamber 14), and the suction valve 57 is open. The pressurizing process is a process of discharging fuel from the pressurizing chamber 14 via the discharge valve unit 70. At this time, the plunger 31 moves toward the top dead center (moves toward the pressurizing chamber 14), and the suction valve 57 is in a closed state.

  In this embodiment, the inlet 11 constitutes an “inlet”, the fuel gallery 13 constitutes a “fuel gallery”, the supply port 132 constitutes a “supply port”, and the supply passage 133 constitutes a “supply passage”. . The suction port 135 constitutes a “suction port”, the pressurization chamber 14 constitutes a “pressurization chamber”, and the suction passage 134 constitutes a “suction passage”. Furthermore, the plunger 31 constitutes a “plunger” and the outlet 71 constitutes an “outlet”.

  As described above in detail, in the high-pressure pump 1 of this embodiment, the supply port 132 and the suction port 135 are formed in the diameter direction passing through the center O in the fuel gallery 13 having a circular shape in plan view. In this case, the virtual vector V1 in the suction direction from the center O toward the suction port 135 and the virtual vector V2 in the supply direction from the supply port 132 toward the center O are in the same direction. Thereby, the fuel can be smoothly guided from the supply port to the suction port, and the fuel can be efficiently sucked in the suction stroke.

As mentioned above, this invention is not limited to the said embodiment at all, In the range which does not deviate from the meaning, it can implement with a various form.
In the above embodiment, as shown in FIG. 2, the virtual vector V1 in the suction direction from the center O toward the suction port 135 and the virtual vector V2 in the supply direction from the supply port 132 toward the center O are in the same direction. . On the other hand, you may form a supply path like the supply path 133a shown with a dashed-two dotted line in FIG. In this case, the angle θ formed by the virtual vector V3 in the supply direction from the supply port 132a of the supply passage 133a toward the center and the virtual vector V1 is an acute angle. Even if it does in this way, the same effect as the above-mentioned form is produced. In realizing the technical idea of the present invention, it is sufficient that the angle formed by the two virtual vectors exceeds a right angle, that is, the inner product is not “0” or less.

  1: High pressure pump, 10: Housing, 11: Inlet (composed of “inlet”), 12: Cover, 13: Fuel gallery (configured of “fuel gallery”), 131: Pulsation damper, 132, 132a: Supply port ( (Constitutes “supply port”), 133, 133a: supply passage (configures “supply passage”), 134: suction passage (configures “suction passage”), 135: suction port (configures “suction port”), 14 : Pressurizing chamber (composing “pressurizing chamber”), 15: cylinder, 30: plunger portion, 31: plunger (constituting “plunger”), 311: large diameter portion, 312: small diameter portion, 32: oil seal holder 323: Seal, 325: Oil seal, 33: Spring seat, 34: Plunger spring, 50: Suction valve part, 51: Tube part, 52: Valve part cover, 53: Connector, 531 Coil, 532: terminal, 533: fixed core, 534: movable core, 535: spring, 55: fuel passage, 56: seat body, 57: intake valve, 58: spring, 59: needle, 70: discharge valve section, 71 : Outlet, 711: Storage chamber, 712: Valve seat, 72: Discharge valve, 73: Spring, 74: Locking part, 75: Discharge port

Claims (5)

An inlet to which fuel is supplied;
A supply passage connecting the inlet to the supply port of the fuel gallery,
A suction passage connecting the suction port of the fuel gallery to the pressurization chamber;
A plunger for creating a volume change of the pressurizing chamber;
An outlet for discharging fuel pressurized in the pressurizing chamber,
The suction port is provided at an end of the fuel gallery in accordance with a first flow direction among a plurality of flow directions in which the fuel easily flows in the fuel gallery.
The supply port is provided at an end of the fuel gallery in accordance with a second flow direction among the plurality of flow directions,
An angle formed between a first virtual vector in the suction direction along the first flow direction and a second virtual vector in the supply direction along the second flow direction is an acute angle or a right angle pump. . An inlet to which fuel is supplied;
A supply passage connecting the inlet to the supply port of the fuel gallery,
A suction passage connecting the suction port of the fuel gallery to the pressurization chamber;
A plunger for creating a volume change of the pressurizing chamber;
An outlet for discharging fuel pressurized in the pressurizing chamber,
The suction port is provided at an end of the fuel gallery in accordance with a first flow direction among a plurality of flow directions in which the fuel easily flows in the fuel gallery.
The supply port is provided at an end of the fuel gallery in accordance with a second flow direction among the plurality of flow directions,
An inner product of a first virtual vector in the suction direction along the first flow direction and a second virtual vector in the supply direction along the second flow direction is “0” or more. . The high-pressure pump according to claim 1 or 2,
The flow direction is a direction in which the distance between the inner walls of the fuel gallery is relatively large. In the high pressure pump according to any one of claims 1 to 3,
The fuel gallery has a circular space in the plan view.
The high-pressure pump according to claim 1, wherein the flow direction is a diametrical direction conceived by the circular space in plan view. In the high pressure pump according to any one of claims 1 to 4,
The high-pressure pump, wherein the first virtual vector and the second virtual vector are in the same direction.

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