JP2008286124A - High pressure fuel pump - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a high pressure fuel pump enabling to improve the performance of lubricating a cam-roller contact portion or others without using oil jet. <P>SOLUTION: The high pressure fuel pump 1 comprises a plunger 23 inserted into a cylinder 21 in a reciprocatively slidable manner, a pressure chamber 22 defined by the cylinder 21 and the plunger 23, a lifter 51 arranged in a lifter guide 52 in a reciprocatively slidable manner, and a compression coil spring 27 for thrusting the lifter 51 to the outer peripheral face side of a cam 111. In the lifter guide 52, an oil passage R1 is formed to discharge lubricating oil from a space 54 encircled by the lifter 51 and the lifter guide 52 to the outside with the reciprocating motion of the lifter 51 due to the rotation of the cam 111. A portion R12 on the outside of the oil passage R1 extends in the direction of guiding the lubricating oil discharged from the oil passage R1 to the cam-roller contact portion P1. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a high-pressure fuel pump that supplies high-pressure fuel to an injector (fuel injection valve) in an internal combustion engine such as an in-cylinder direct injection engine.

  In-cylinder direct injection engines mounted on automobiles and the like, fuel injection must be performed with the fuel pressure higher than the pressure in the combustion chamber. Therefore, the fuel sent from the fuel tank is added by a high-pressure fuel pump. The pressure is supplied to the injector.

  As a fuel supply system for a direct injection type in-cylinder engine, for example, a feed pump that feeds fuel from a fuel tank, a high-pressure fuel pump that pressurizes the fuel sent by the feed pump, and a fuel that is pressurized by the high-pressure fuel pump There is known one that includes a delivery pipe for storing the fuel and an injector arranged for each cylinder of the engine. The high-pressure fuel stored in the delivery pipe by the valve opening control of each injector is directly injected from the injector into the fuel chamber.

  As a high-pressure fuel pump used in such a fuel supply system, for example, a plunger inserted in a cylinder so as to be reciprocally slidable, a pressurizing chamber defined by the cylinder and the plunger, a lifter guide Some of them include a lifter connected to a plunger and a compression coil spring that presses the lifter toward the outer peripheral surface of the cam. When the cam nose is retracted from the lifter as the cam rotates, the plunger moves to increase the volume of the pressurizing chamber (intake stroke), and the cam nose of the cam pushes the lifter, and the plunger moves accordingly. In this structure, the fuel is pressurized and supplied to the delivery pipe or the like by repeating the process of reducing the volume of the pressurizing chamber (pressurizing process).

By the way, in the high-pressure fuel pump having the structure as described above, the outer peripheral surface of the cam is in contact with the bottom surface of the lifter or the outer peripheral surface of the roller rotatably supported by the lifter. It is desirable to lubricate by supplying lubricating oil (oil) to the bottom surface or the contact portion with the outer peripheral surface of the roller. For this reason, conventionally, in order to improve the lubricity at the contact portion, an oil jet that injects the lubricant oil toward the contact portion is provided to actively supply the lubricant. As shown in FIG. 1, measures are taken such as providing a hole in the bottom surface of the lifter and supplying lubricating oil inside the lifter through the hole.
JP 2003-269296 A

  However, the measures for providing the above-described oil jet in the high-pressure fuel pump have the following problems. That is, an oil jet is required separately. Along with this, a lubricating oil supply path to the oil jet must be secured. However, disposing the lubricating oil supply path in the cylinder head having a complicated shape increases the labor of processing and its design is difficult. In addition, depending on the installation location of the oil jet, the lubricating oil supply path from the hydraulic pressure source becomes long, and the hydraulic pressure decreases greatly. For this reason, in order to inject lubricating oil to the contact portion (cam / lifter contact portion or cam / roller contact portion) by an oil jet, the hydraulic pressure of the hydraulic source must be set high.

  By the way, depending on the mounting direction of the high-pressure fuel pump in the engine, a plunger or a lifter may be disposed above the pressurizing chamber, and a cam may be disposed further above. In this case, even if measures are taken to provide a hole in the bottom surface of the lifter described above, lubricating oil cannot be supplied to the contact portion. Further, in this case, there is a possibility that the lubricating oil flows in one after another from the lifter side to the inside of the pump, specifically, the space surrounded by the lifter and the lifter guide. Then, the lubricating oil that has flowed into the pump is compressed by the reciprocating movement of the lifter, which may cause an excessive increase in driving torque and damage to the pump components.

  The present invention has been made in consideration of such problems, and can improve the lubricity of the contact portion without using an oil jet, and can be driven by the reciprocating motion of the lifter. An object of the present invention is to provide a high-pressure fuel pump capable of avoiding an excessive increase in torque and damage to pump parts.

  The present invention has been made in consideration of such problems, and can improve the lubricity of the contact portion without using an oil jet, and can be driven by the reciprocating motion of the lifter. An object of the present invention is to provide a high-pressure fuel pump capable of avoiding an excessive increase in torque and damage to pump parts.

  In the present invention, means for solving the above-described problems are configured as follows. That is, the present invention is a high-pressure fuel pump, a plunger inserted in a cylinder so as to be reciprocally slidable, a pressure chamber defined by the cylinder and the plunger, and reciprocally slid in a lifter guide A lifter arranged in a possible manner and a compression coil spring that presses the lifter toward the outer peripheral surface of the cam. The plunger moves reciprocally as the cam rotates, and the plunger By reciprocating, the fuel suction into the pressurizing chamber and the pressurization / discharge of the fuel in the pressurizing chamber are repeated.

  In such a high-pressure fuel pump, the lifter guide is configured to discharge the lubricating oil in the space surrounded by the lifter and the lifter guide to the outside as the lifter reciprocates due to the rotation of the cam. An oil passage is formed, and the portion on the outer side of the oil passage can guide the lubricating oil discharged from the oil passage to a contact portion between the cam and a member in contact with the outer peripheral surface of the cam. It is characterized by extending in various directions.

  Here, examples of the member in contact with the outer peripheral surface of the cam include a lifter and a roller rotatably supported by the lifter. In other words, the present invention can be applied to a high pressure fuel pump having a so-called direct hitting lifter structure in which the cam and the lifter are in contact, and also to a high pressure fuel pump having a so-called roller lifter structure in which the cam and the roller are in contact. Is possible.

  According to the above configuration, when the plunger moves in the direction in which the volume of the pressurizing chamber contracts due to the rotation of the cam (pressurization stroke), the space surrounded by the lifter and the lifter guide as the lifter moves. As a result, the lubricating oil in the space is discharged to the outside through the oil passage. Thus, the lubricating oil is forcibly discharged through the oil passage by the pump action accompanying the reciprocating motion of the lifter. Thus, since the lubricating oil in the space is released to the outside through the oil passage, it is possible to avoid an increase in the amount of lubricating oil in the space even if the lubricating oil flows into the space. Thereby, even if the lubricating oil in the space is compressed by the reciprocating motion of the lifter, it is possible to avoid an excessive increase in driving torque and damage to the pump parts.

  Since the portion on the outside of the oil passage extends toward the contact portion between the cam and the member in contact with the outer peripheral surface of the cam, the discharge direction of the lubricating oil discharged through the oil passage is the contact portion. It becomes the direction to go. Thereby, since lubricating oil is guided toward the contact part, it becomes possible to lubricate this contact part directly. In addition, since the lubricating oil is actively fed to the contact portion by utilizing the pump action associated with the reciprocating motion of the lifter, the lubricating oil is in a state where it has a certain degree of momentum, and to some extent depending on the external part. In a state where the direction of is regulated, it is discharged toward the contact portion. Thereby, lubricating oil can be supplied to the contact part sufficiently and efficiently. Accordingly, the lubricity at the contact portion can be improved without using an oil jet, and friction can be reduced.

  Here, the oil passage is provided with a branch portion branched in the middle of the oil passage, and the branch end of the branch portion is communicated with the sliding portion between the lifter and the lifter guide. Is preferred. In this way, since the lubricating oil is supplied to the sliding portion between the lifter and the lifter guide through the branch portion of the oil passage, it is possible to reduce wear on the outer peripheral surface of the lifter and the inner peripheral surface of the lifter guide.

  In this case, it is preferable that the branch end of the branch portion is provided in a portion of the lifter guide where the lifter is always in sliding contact. In other words, it is preferable to set the height position of the branch end of the branch portion in the lifter guide to a portion where the lifter always slides. Specifically, the lifter's reciprocating region is determined according to the cam nose height, so that the cam nose height is removed from both ends (top dead center and bottom dead center) of the reciprocating region. The region is a portion where the lifter is always in sliding contact with the lifter guide. In the part where the lifter is always in sliding contact with the lifter guide, it is difficult to supply the lubricating oil, so by providing a branching end of the branching part in that part, lubrication of the sliding part between the lifter and the lifter guide is effective. You can plan.

  The oil passage is preferably provided with a check valve that allows the lubricating oil to flow out of the space and prevents the lubricating oil from flowing into the space. If it carries out like this, it can prevent that the lubricating oil supplied to the contact part of the cam and the member which contact | connects the outer peripheral surface of this cam is sucked in the space, and suppresses the fall of the lubricity in the contact part. be able to.

  According to the present invention, when the plunger moves in the direction in which the volume of the pressurizing chamber contracts due to the rotation of the cam (pressurization stroke), the space enclosed by the lifter and the lifter guide as the lifter moves. As a result, the lubricating oil in the space is discharged to the outside through the oil passage. Thus, the lubricating oil is forcibly discharged through the oil passage by the pump action accompanying the reciprocating motion of the lifter. Thus, since the lubricating oil in the space is released to the outside through the oil passage, it is possible to avoid an increase in the amount of lubricating oil in the space even if the lubricating oil flows into the space. Thereby, even if the lubricating oil in the space is compressed by the reciprocating motion of the lifter, it is possible to avoid an excessive increase in driving torque and damage to the pump parts.

  Since the portion on the outside of the oil passage extends toward the contact portion between the cam and the member in contact with the outer peripheral surface of the cam, the discharge direction of the lubricating oil discharged through the oil passage is the contact portion. It becomes the direction to go. Thereby, since lubricating oil is guided toward the contact part, it becomes possible to lubricate this contact part directly. In addition, since the lubricating oil is actively fed to the contact portion by utilizing the pump action associated with the reciprocating motion of the lifter, the lubricating oil is in a state where it has a certain degree of momentum, and to some extent depending on the external part. In a state where the direction of is regulated, it is discharged toward the contact portion. Thereby, lubricating oil can be supplied to the contact part sufficiently and efficiently. Accordingly, the lubricity at the contact portion can be improved without using an oil jet, and friction can be reduced.

  The best mode for carrying out the present invention will be described with reference to the accompanying drawings.

  Below, the case where this invention is applied to the high pressure fuel pump used for the cylinder direct injection type multi-cylinder (for example, 6 cylinders) gasoline engine mounted in a motor vehicle is demonstrated.

-Fuel supply device 100-
Before describing the specific configuration of the high-pressure fuel pump, the schematic configuration of the fuel supply apparatus 100 to which the high-pressure pump is applied will be described with reference to FIG.

  A fuel supply apparatus 100 illustrated in FIG. 1 includes a feed pump 102 that feeds fuel from a fuel tank 101, and pressurizes the fuel fed by the feed pump 102 to inject the injectors 4, 4,. And a high-pressure fuel pump 1 that discharges toward

  The high-pressure fuel pump 1 includes a cylinder 21, a plunger 23, a pressurizing chamber 22, and an electromagnetic spill valve 30.

  The plunger 23 is driven by the rotation of a cam 111 attached to the intake camshaft 110 of the engine, and reciprocates in the cylinder 21. By the reciprocating movement of the plunger 23, the volume of the pressurizing chamber 22 is enlarged or reduced. In this embodiment, three cam peaks (cam noses) 112, 112, 112 are formed in the cam 111 with an angular interval of 120 ° around the rotation axis of the intake camshaft 110. The plunger 23 is pushed down by the three cam noses 112, 112, 112, and the plunger 23 moves in the cylinder 21. In this embodiment, the high-pressure fuel pump 1 is mounted on the engine in such a direction that a plunger 23 and a later-described lifter 51 are disposed above the pressurizing chamber 22 and a cam 111 is disposed further upward.

  In this embodiment, since the engine is a 6-cylinder type, during each cycle of the engine, that is, while the crankshaft rotates twice, each of the injectors 4 provided for each cylinder has a total of 6 Fuel injection is performed once. In addition, for each cycle of the engine, the intake camshaft 110 rotates once, and the discharge operation from the high-pressure fuel pump 1 is performed three times.

  The pressurizing chamber 22 is partitioned by a plunger 23 and a cylinder 21. The pressurizing chamber 22 communicates with the feed pump 102 via the low pressure fuel pipe 104. The pressurizing chamber 22 communicates with a delivery pipe (pressure accumulating vessel) 106 through a high-pressure fuel pipe 105.

  Six injectors 4, 4,... Are connected to the delivery pipe. The delivery pipe 106 is provided with a fuel pressure sensor 161 that detects the fuel pressure (actual fuel pressure) inside the pipe. A return pipe 172 is connected to the delivery pipe 106 via a relief valve 171.

  The relief valve 171 opens when the fuel pressure in the delivery pipe 106 exceeds a predetermined pressure (for example, 13 MPa). By opening the relief valve 171, a part of the fuel stored in the delivery pipe 106 is returned to the fuel tank 101 via the return pipe 172. Thereby, an excessive increase in the fuel pressure in the delivery pipe 106 is prevented.

  Further, the return pipe 172 and the high-pressure fuel pump 1 are connected by a fuel discharge pipe 108 (shown by a broken line in FIG. 1), and the fuel leaked from the gap between the plunger 23 and the cylinder 21 of the high-pressure fuel pump 1 is sealed. The fuel is stored in the fuel storage chamber 6 below the unit 5 and then returned to the fuel discharge pipe 108 connected to the fuel storage chamber 6.

  The low pressure fuel pipe 104 is provided with a filter 141 and a pressure regulator 142. The pressure regulator 142 returns the fuel in the low-pressure fuel pipe 104 to the fuel tank 101 when the fuel pressure in the low-pressure fuel pipe 104 exceeds a predetermined pressure (for example, 0.4 MPa). The fuel pressure is maintained below a predetermined pressure.

  Further, a pulsation damper 107 is provided in the low pressure fuel pipe 104, and the pulsation damper 107 suppresses fuel pressure pulsation in the low pressure fuel pipe 104 when the high pressure fuel pump 1 is operated. . Further, the high pressure fuel pipe 105 is provided with a check valve 151 for preventing the fuel discharged from the high pressure fuel pump 1 from flowing backward.

  The high-pressure fuel pump 1 is provided with an electromagnetic spill valve 30 for communicating or blocking between the low-pressure fuel pipe 104 and the pressurizing chamber 22. The electromagnetic spill valve 30 includes an electromagnetic solenoid 31 and opens and closes by controlling energization of the electromagnetic solenoid 31.

  Next, the opening / closing operation of the electromagnetic spill valve 30 will be described with reference to FIG.

  First, when the energization of the electromagnetic solenoid 31 is stopped, the electromagnetic spill valve 30 is opened by the elastic force of the compression coil spring 37, and the low pressure fuel pipe 104 and the pressurizing chamber 22 are in communication with each other. In this state, when the cam 111 rotates together with the intake camshaft 110 and the plunger 23 moves in the direction in which the volume of the pressurizing chamber 22 increases (in the direction in which the plunger 23 rises in FIG. 1) (intake stroke). The fuel delivered from the feed pump 102 is sucked into the pressurizing chamber 22 through the low-pressure fuel pipe 104.

  On the other hand, when the cam 111 rotates together with the intake camshaft 110 and the plunger 23 moves in the direction in which the volume of the pressurizing chamber 22 contracts (the direction in which the plunger 23 descends in FIG. 1) (pressurization stroke), electromagnetic When the electromagnetic spill valve 30 is closed against the elastic force of the compression coil spring 37 by energizing the solenoid 31, the low-pressure fuel pipe 104 and the pressurizing chamber 22 are disconnected, and the fuel pressure in the pressurizing chamber 22 is blocked. When the valve reaches a predetermined value, the check valve 40 is opened, and high-pressure fuel is discharged toward the delivery pipe 106 through the high-pressure fuel pipe 105.

  The fuel discharge amount in the high-pressure fuel pump 1 is adjusted by controlling the closing period of the electromagnetic spill valve 30 in the pressurization stroke. That is, if the closing time of the electromagnetic spill valve 30 is advanced and the closing period is lengthened, the fuel discharge amount increases. If the closing start time of the electromagnetic spill valve 30 is delayed and the closing period is shortened, the fuel discharge amount decreases. To come. In this manner, the fuel pressure in the delivery pipe 106 is controlled by adjusting the fuel discharge amount of the high-pressure fuel pump 1.

  Here, the pump duty DT which is a control amount for controlling the fuel discharge amount of the high-pressure fuel pump 1 (the valve closing start timing of the electromagnetic spill valve 30) will be described. This pump duty DT varies between 0% and 100%, and is a value related to the cam angle of the cam 111 of the intake camshaft 110 corresponding to the valve closing period of the electromagnetic spill valve 30.

  Specifically, with respect to the cam angle of the cam 111, as shown in FIG. 2, the cam angle (maximum cam angle) corresponding to the maximum valve closing period of the electromagnetic spill valve 30 is θ0, and the target fuel pressure in the maximum valve closing period is set. If the cam angle (target cam angle) corresponding to is θ, the pump duty DT is expressed as a ratio of the target cam angle θ to the maximum cam angle θ0 (DT = θ / θ0). Accordingly, the pump duty DT becomes closer to 100% as the closing period (closing timing) of the target electromagnetic spill valve 30 approaches the maximum closing period, and the target closing period approaches “0”. The value is closer to 0%.

  And as the pump duty DT approaches 100%, the valve closing start timing of the electromagnetic spill valve 30 adjusted based on the pump duty DT is advanced, and the valve closing period of the electromagnetic spill valve 30 becomes longer. As a result, the fuel discharge amount of the high-pressure fuel pump 1 increases and the actual fuel pressure increases. Further, as the pump duty DT approaches 0%, the valve closing start timing of the electromagnetic spill valve 30 adjusted based on the pump duty DT is delayed, and the valve closing period of the electromagnetic spill valve 30 is shortened. As a result, the fuel discharge amount of the high-pressure fuel pump 1 is reduced and the actual fuel pressure is lowered. The details of the procedure for calculating the pump duty DT are omitted here.

-Specific configuration of high-pressure fuel pump 1-
Next, a specific configuration of the high-pressure fuel pump 1 will be described with reference to FIG. FIG. 3 is a longitudinal sectional view showing a first embodiment of the high-pressure fuel pump according to the present invention.

  The high-pressure fuel pump 1 illustrated in FIG. 3 is a plunger type pump, and includes a pump unit 20 provided in the housing 10, an electromagnetic spill valve 30, and a check valve 40.

  The pump unit 20 includes a cylinder 21, a pressurizing chamber 22, a plunger 23, and a lifter 51. The cylinder 21 is formed at the center of the housing 10, and a pressurizing chamber 22 is formed on the tip side (the lower end side in FIG. 3). The plunger 23 is a substantially cylindrical member, and is inserted into the cylinder 21 so as to be slidable in the axial direction (the vertical direction here).

  The lifter 51 is a cylindrical member with a bottom, and accommodates a proximal end portion (upper end portion) of the plunger 23, a retainer 26, a compression coil spring 27, and the like. The upper portion of the lifter 51 is a roller support portion 51b, and a roller 53 that is rotatable about an axis extending parallel to the axis of the intake camshaft 110 is supported on the roller support portion 51b. . The lower end of the roller 53 can come into contact with the outer peripheral surface of the cam 111. Thus, the lifter 51 is configured as a so-called roller lifter. The roller 53 can be supported by a rotating shaft 53a fixed to the roller support portion 51b via a large number of rollers, for example. In this embodiment, lubricating oil is supplied to a contact portion (cam / roller contact portion) P1 between the outer peripheral surface of the cam 111 and the outer peripheral surface of the roller 53 to improve the lubricity in the cam / roller contact portion P1. I try to let them. A configuration for supplying lubricating oil to the cam / roller contact portion P1 will be described later.

  The lifter guide 52 is formed, for example, in a cylindrical shape, and the lifter 51 is accommodated in the cylindrical space so as to be slidable in the axial direction. A pin for preventing the lifter 51 from rotating about the axis is attached to the lifter guide 52. The pin is a rod-shaped member and is integrally supported by the lifter guide 52 (see FIG. 4).

  A retainer 26 is integrally attached to the proximal end portion of the plunger 23. A spring seat member 52 a is fitted in the lower part of the lifter guide 52. A compression coil spring 27 is sandwiched between the upper surface of the spring seat member 52 a and the retainer 26. By the elastic force of the compression coil spring 27, an urging force in the direction in which the plunger 23 is pushed up (the direction in which the volume of the pressurizing chamber 22 is expanded) is applied, and the roller 53 supported by the lifter 51 is directed toward the cam 111. Is pressed.

  Here, when the cam 111 rotates together with the intake camshaft 110, the cam nose 112 of the cam 111 applies a downward pressing force to the roller 53 of the lifter 51, so that the lifter 51 and the plunger 23 are lowered and the compression coil The spring 27 is compressed to reduce the volume of the pressurizing chamber 22. On the other hand, when the cam nose 112 moves away from the roller 53 of the lifter 51, the lifter 51 and the plunger 23 are raised by the urging force of the compression coil spring 27, and the volume of the pressurizing chamber 22 is increased.

  The electromagnetic spill valve 30 is disposed to face the pressurizing chamber 22. The electromagnetic spill valve 30 includes an electromagnetic solenoid 31, a bobbin 32, a core 33, an armature 34, a poppet valve 35, and a seat body 36. The electromagnetic solenoid 31 includes a coil wound around the bobbin 32 in a ring shape, and a core 33 is fitted and fixed in the central through hole of the bobbin 32. A portion of the armature 34 is fixed to one end of the poppet valve 35, and a part of the armature 34 is disposed coaxially with the core 33 so as to enter the central through hole of the bobbin 32. Concave portions are formed on the opposing surfaces of the core 33 and the armature 34, and a compression coil spring 37 is housed in a compressed state between the concave portions. The armature 34 is urged toward the pressurizing chamber 22 by the elastic force of the compression coil spring 37. The poppet valve 35 is slidably inserted into a through hole in the sheet body 36. A disc-shaped valve body 35 a is formed at the lower end of the poppet valve 35.

  In the above configuration, when the electromagnetic solenoid 31 is not energized, the valve body 35a is separated from the seat portion 36a of the seat body 36 by the elastic force of the compression coil spring 37, and the electromagnetic spill valve 30 is opened. On the other hand, when the electromagnetic solenoid 31 is energized by supplying power to the terminal 38, a magnetic circuit is formed by the support member 39 that supports the core 33, the armature 34, and the electromagnetic spill valve 30 as a whole. On the contrary, the armature 34 moves to the core 33 side. As a result, the poppet valve 35 moves to the side opposite to the pressurizing chamber 22, the valve body 35a comes into contact with the seat portion 36a of the seat body 36, and the electromagnetic spill valve 30 is closed (shown in FIG. 3). Status).

  On the other hand, when the electromagnetic spill valve 30 is in the open state, fuel can flow between the plurality of supply passages 36 b formed in the seat body 36 and the pressurizing chamber 22.

  A low pressure fuel passage 11 is formed in the housing 10 so as to communicate with the supply passage 36b. Then, when the plunger 23 rises with the electromagnetic spill valve 30 opened, the low pressure fuel pumped from the fuel tank 101 by the operation of the feed pump 102 is filtered, the pressure regulator 142, the low pressure fuel passage 11, and The air is sucked into the pressurizing chamber 22 through the supply passage 36b.

  The pressurizing chamber 22 formed on the tip side of the cylinder 21 is formed with a larger diameter than the inner peripheral surface of the cylinder 21. The plunger 23 enters the pressurizing chamber 22 before the closing timing of the electromagnetic spill valve 30, and the plunger 23 reaches the top dead center after the electromagnetic spill valve 30 is closed. In addition, a gap is formed between the inner peripheral surface of the pressurizing chamber 22 and the outer peripheral surface of the plunger 23 in a state where the distal end portion of the plunger 23 has entered the pressurizing chamber 22. A high pressure fuel passage 12 is formed in the housing 10, and the pressurizing chamber 22 communicates with the check valve 40 through the high pressure fuel passage 12.

  The check valve 40 includes a casing 41 connected to the high-pressure fuel passage 12, a seat body 42 and a spring base body 45 disposed in the casing 41, and a valve body (valve) facing the seat body 42 so as to be able to contact and separate. Body) 43 and a compression coil spring 44 that urges the valve body 43 toward a contact position with respect to the seat body 42. The check valve 40 is connected to the high-pressure fuel pipe 105. When the pressure of fuel pumped from the pressurizing chamber 22 through the high pressure fuel passage 12 exceeds a predetermined value, the valve body 43 separates from the seat body 42 against the urging force of the compression coil spring 44. Moved to position. As a result, the check valve 40 is opened, and the high pressure fuel pumped from the high pressure fuel passage 12 is supplied to the delivery pipe 106 via the high pressure fuel pipe 105.

-Characteristic part of embodiment (supply of lubricating oil to cam / roller contact part)-
Next, a characteristic part of this embodiment, that is, a configuration for supplying lubricating oil to the cam / roller contact portion P1 in the high-pressure fuel pump 1 will be described. In this embodiment, for example, without providing an oil jet that injects lubricating oil toward the cam / roller contact portion P1, lubricating oil is supplied to the cam / roller contact portion P1, and the cam / roller contact portion is supplied. The lubricity in P1 is improved.

  Here, since the high-pressure fuel pump 1 is mounted in such a direction that the plunger 23 and the lifter 51 are disposed above the pressurizing chamber 22 and the cam 111 is disposed further upward, the lubricating oil is introduced from the lifter 51 side. There is a possibility that the air will flow into the pump 54, specifically, the space 54 surrounded by the lifter 51, the lifter guide 52, and the inner surfaces of the spring seat member 52a. Therefore, in this embodiment, a configuration is adopted in which the lubricating oil in the space 54 is allowed to escape to the outside and an oil passage is provided for supplying the lubricating oil to the cam / roller contact portion P1. This specific configuration will be described below with reference to three examples.

(First embodiment)
First, the first embodiment will be described with reference to FIGS. 4 is a view taken in the direction of arrow A in FIG. In FIG. 4, the cam 111 is omitted.

  The lifter 51 of the high-pressure fuel pump 1 is formed with a pair of flat surface portions (two-surface width portions) 51a and 51a extending in parallel with each other along the axial direction. The pair of flat portions 51a and 51a are provided symmetrically with an angular interval of 180 ° around the axis of the lifter 51, and the outer shape of the lifter 51 is not circular when viewed from the axial direction, but a pair of flat portions 51a and 51a. It has a substantially oval shape that is recessed inward by 51a.

  The pair of flat portions 51 a and 51 a of the lifter 51 are provided to prevent rotation of the lifter 51 around the axis by the pins 55. The pair of plane portions 51a and 51a are provided symmetrically in order to improve the assembling property of the lifter 51. A pin 55 is in contact with one of the pair of flat portions 51a and 51a. Due to the engagement between the one flat portion 51a and the pin 55, rotation of the lifter 51 around the axis is prevented. Note that the rotation of the lifter 51 around the axis may be prevented by means other than the pin 55. Also, the outer shape of the lifter 51 may be a shape other than those described above.

  The gap between the lifter 51 and the lifter guide 52 is larger in the pair of flat portions 51a and 51a than in the other portions. Here, since the pin 55 is in contact with the one flat portion 51a on the pin 55 side, the presence of the pin 55 prevents the flow of the lubricating oil. On the other hand, such a member such as a pin is not provided in the gap C1 between the lifter 51 and the lifter guide 52 by the other flat portion 51a on the side opposite to the pin 55. The gap C1 communicates with a space 54 surrounded by the inner surfaces of the lifter 51, the lifter guide 52, and the spring seat member 52a. For this reason, the lubricating oil can flow out from the space 54 and the lubricating oil can flow into the space 54 through the gap C1. Note that the gap between the lifter 51 and the lifter guide 52 is narrow except for the pair of flat portions 51a and 51a. For this reason, it is difficult to distribute the lubricating oil through the narrow gap, and even if distributed, the amount is very small.

  The lifter guide 52 is formed with an oil passage R1 for releasing the lubricating oil in the space 54 to the outside and supplying the lubricating oil to the cam / roller contact portion P1. The oil passage R1 is a space having a circular cross section and a predetermined cross sectional area. The cross-sectional shape of the oil passage R1 may be other than a circle. The cross-sectional area of the oil passage R1 is preferably set as large as possible in order to increase the discharge amount of the lubricating oil and to reduce the oil passage resistance when the lubricating oil is discharged.

  One end R1a of the oil passage R1 communicates with the space 54 below the lifter 51, and the other end R1b communicates with the external space. The oil passage R1 is bent in the middle, and the extending direction is changed. That is, the portion R11 on one end side (space 54 side) and the portion R12 on the other end side (external space side) are connected at a predetermined angle inside the lifter guide 52.

  The portion R11 on one end side extends obliquely upward and outward from one end R1a to the connection end R1c. On the other hand, the other end portion R12 extends obliquely upward and inward from the connection end R1c to the other end R1b. The extending direction of the portion R12 on the other end side is set so that the lubricating oil discharged from the oil passage R1 can be guided to the cam / roller contact portion P1. The angle at which the oil passage R1 bends, that is, the angle at which the portion R11 on one end side and the portion R12 on the other end side are connected is to reduce the oil passage resistance when the lubricating oil is discharged. It is preferable to set the angle as gentle as possible.

  The oil passage R1 is provided at a position different from the flat portions 51a and 51a of the lifter 51 by 90 degrees around its axis. That is, the oil passage R <b> 1 is provided so as to be orthogonal to the rotation axis direction of the roller 53. One end R1a of the oil passage R1 is located below the flat portions 51a and 51a of the lifter 51. More specifically, one end R1a of the oil passage R1 is located at a position different from the flat portions 51a, 51a of the lifter 51 by 90 degrees around its axis.

  Such an oil passage R1 can be formed by drilling the lifter guide 52, for example. In this case, the oil passage R1 is easily formed in the lifter guide 52 by performing drilling of the portion R11 on the one end side and drilling of the portion R12 on the other end side once for the lifter guide 52. can do.

  For example, lubricating oil from an engine oil pump is supplied into the space 54, and the lubricating oil is supplied into the space 54 through an oil passage (oil hole) formed in the lifter guide 52 or the like. Is possible. Further, as described above, the lubricating oil flows into the space 54 from the lifter 51 side. In this case, the lubricating oil flows into the space 54 through the oil passage R1, the gap C1, and the like.

  Specifically, when the plunger 23 moves in the direction in which the volume of the pressurizing chamber 22 increases due to the rotation of the cam 111 (intake stroke), the lifter 51 rises and the volume of the space 54 increases. As a result, the pressure in the space 54 decreases, and the lubricating oil is sucked into the space 54. At this time, the lubricating oil flows into the space 54 from the oil passage, the oil passage R1, the gap C1, and the like.

  On the other hand, when the plunger 23 moves in the direction in which the volume of the pressurizing chamber 22 contracts due to the rotation of the cam 111 (pressurization stroke), the lifter 51 is lowered. As the lifter 51 moves, the pressure in the space 54 increases, and as a result, the lubricating oil in the space 54 is forcibly discharged (released) to the outside through the oil passage R1 and the gap C1.

  Here, since the amount of lubricating oil that escapes from the gap C1 when the lifter 51 is lowered is limited, the following problem may occur if the oil passage R1 is not provided. That is, the high-pressure fuel pump 1 is mounted in such a direction that the lubricating oil may flow into the space 54 one after another from the lifter 51 side. For this reason, if there is little quantity of the lubricating oil escaped from the clearance C1 compared with the quantity of the lubricating oil flowing in into the space 54, the quantity of the lubricating oil in the space 54 will increase gradually. As a result, the lubricating oil that has flowed into the space 54 due to the reciprocating motion of the lifter 51 is compressed, which may lead to an excessive increase in driving torque and damage to pump components.

  In this example, the lubricating oil in the space 54 is fed not only from the gap C1 between the lifter 51 and the lifter guide 52 but also through the lifter guide 52 by the pump action accompanying the reciprocating movement of the lifter 51 up and down. The discharge is also forced from the path R1. Thus, since the lubricating oil in the space 54 is released to the outside through the oil passage R1, it is avoided that the amount of the lubricating oil in the space 54 increases even if the lubricating oil flows into the space 54. Is done. Thereby, even if the lubricating oil in the space 54 is compressed by the reciprocating motion of the lifter 51, it is possible to avoid an excessive increase in driving torque and damage to pump parts.

  Since the portion R12 on the other end side of the oil passage R1 extends toward the cam / roller contact portion P1, the discharge direction of the lubricating oil discharged through the oil passage R1 is directed toward the cam / roller contact portion P1. Become a direction. Thus, since the lubricating oil is guided toward the cam / roller contact portion P1, the cam / roller contact portion P1 can be directly lubricated. Further, since the lubricating oil is positively sent to the cam / roller contact portion P1 by utilizing the pump action accompanying the reciprocating movement of the lifter 51 up and down, the lubricating oil has a certain momentum, In addition, the light is discharged toward the cam / roller contact portion P1 in a state where the direction is restricted (squeezed) to some extent by the portion R12 on the other end side. As a result, the lubricating oil can be supplied to the cam / roller contact portion P1 sufficiently and efficiently. Therefore, the lubricity in the cam / roller contact portion P1 can be improved without using an oil jet, and friction can be reduced.

  Next, a modification of the first embodiment will be described.

  (1) The high pressure fuel pump 1 may have a so-called direct hitting type lifter in which the cam 111 and the lifter 51 are in contact with each other. In this case, it is possible to supply lubricating oil to the contact portion (cam / lifter contact portion) between the outer peripheral surface of the cam 111 and the bottom surface of the lifter 51 via the oil passage R1 as described above. In the case of this direct hitting type lifter, it is not particularly necessary to prevent the lifter 51 from rotating by the pin 55 or the like.

  (2) The shape of the oil passage R1 is not particularly limited, and may be other than the above-described one in which the one end R11 and the other end R12 are connected at a predetermined angle. Further, the arrangement position of the oil passage R1 of the lifter guide 52 is not particularly limited, and may be other than the position different by 90 degrees around the axis with respect to the flat portions 51a and 51a of the lifter 51 as described above. However, it is necessary to set the direction in which the portion of the oil passage R1 on the outer space side extends so that the lubricating oil discharged from the oil passage R1 can be guided to the cam / roller contact portion P1.

  (3) The lifter guide 52 may be provided with a plurality of oil passages R1. For example, as shown in FIG. 5, two oil passages R <b> 1 and R <b> 1 can be provided in the lifter guide 52. The two oil passages R1 and R1 are provided symmetrically around the axis of the lifter 51 with an angular interval of 180 °. The two oil passages R1 and R1 are provided at positions different from the flat portions 51a and 51a of the lifter 51 by 90 degrees around the axis. That is, the two oil passages R1 and R1 are provided so as to be orthogonal to the rotation axis direction of the roller 53, respectively. In this way, if the lifter guide 52 is provided with the two oil passages R1, R1, the lubricating oil is supplied to the cam / roller contact portion P1 not only from one side but from both sides. The lubricity in P1 can be further improved, which is effective.

(Second embodiment)
Next, a second embodiment will be described with reference to FIG. The second embodiment is an improvement of the first embodiment, and in the high-pressure fuel pump 1, the lubricating oil in the space 54 is not only released to the outside and supplied to the cam / roller contact portion P 1 but also the lifter. The point which supplies also to the sliding part P2 of 51 and the lifter guide 52 differs from the case of the said 1st Example. Here, different points will be mainly described, and the same components (see FIGS. 3 and 4) as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof will be omitted.

  In this example, in order to guide the lubricating oil in the space 54 to the cam / roller contact portion P1 and the sliding portion P2 between the lifter 51 and the lifter guide 52, an oil passage R2 as shown in FIG. Provided. The oil passage R2 in this example has a configuration in which a branch portion R23 is added to the oil passage R1 in the first embodiment (see FIGS. 3 and 4).

  Specifically, the oil passage R2 is branched at a portion R21 on one end side (space 54 side), a portion R22 on the other end side (external space side), and a portion R21 on the one end side (connection end R2d). And a branch portion R23.

  The one end R21 and the other end R22 are connected at a predetermined angle. The one end portion R21 extends obliquely upward and outward from one end R2a to the connection end R2d. On the other hand, the other end portion R22 extends obliquely upward and inward from the connection end R2d to the other end R2b. The extending direction of the portion R22 on the other end side is set so as to guide the lubricating oil discharged from the oil passage R2 to the cam / roller contact portion P1.

  Further, the branch portion R23 is branched from the portion R21 on one end side at a predetermined angle. The branch portion R23 extends diagonally upward and inward from the connection end R2e to the branch end R2c. In this case, the branch portion R23 is provided in parallel with the portion R22 on the other end side. That is, the angle at which the end portion R21 and the other end portion R22 are connected is the same as the angle at which the branch portion R23 branches from the end portion R21.

  One end R2a of the oil passage R2 communicates with the space 54 below the lifter 51, and the other end R2b communicates with the external space. The branch end R <b> 2 c communicates with a gap between the lifter 51 and the lifter guide 52, that is, a sliding portion P <b> 2 between the lifter 51 and the lifter guide 52.

  The oil passage R2 is provided at a position different from the flat portions 51a and 51a of the lifter 51 by 90 degrees around its axis. That is, the oil passage R <b> 2 is provided so as to be orthogonal to the rotation axis direction of the roller 53. One end R2a of the oil passage R2 is located below the portions of the lifter 51 other than the flat portions 51a and 51a. A branch end R2c of the oil passage R2 communicates with a gap between the lifter 51 and the lifter guide 52 at a portion other than the flat portions 51a and 51a of the lifter 51. More specifically, the one end R2a and the branch end R2c of the oil passage R2 are located at positions different from the flat portions 51a and 51a of the lifter 51 by 90 degrees around the axis.

  Such oil passage R2 can be formed, for example, by drilling the lifter guide 52. In this case, the lifter guide 52 can be drilled into the lifter guide 52 only once by drilling the portion R21 on one end side, drilling the portion R22 on the other end side, and drilling the branch portion R23. The oil passage R2 can be easily formed.

  In this example, the lubricating oil in the space 54 is fed not only from the gap C1 between the lifter 51 and the lifter guide 52 but also through the lifter guide 52 by the pump action accompanying the reciprocating movement of the lifter 51 up and down. The discharge is also forced from the path R2. Thus, since the lubricating oil in the space 54 is released to the outside through the oil passage R2, even if the lubricating oil flows into the space 54, an increase in the amount of the lubricating oil in the space 54 is avoided. Is done. Thereby, even if the lubricating oil in the space 54 is compressed by the reciprocating motion of the lifter 51, it is possible to avoid an excessive increase in driving torque and damage to pump parts.

  Since the portion R22 on the other end side of the oil passage R2 extends toward the cam / roller contact portion P1, the discharge direction of the lubricating oil discharged through the oil passage R2 is directed toward the cam / roller contact portion P1. Become a direction. Thus, since the lubricating oil is guided toward the cam / roller contact portion P1, the cam / roller contact portion P1 can be directly lubricated. Further, since the lubricating oil is positively sent to the cam / roller contact portion P1 by utilizing the pump action accompanying the reciprocating movement of the lifter 51 up and down, the lubricating oil has a certain momentum, Moreover, it is discharged toward the cam / roller contact portion P1 in a state where the direction is restricted to some extent by the portion R22 on the other end side. As a result, the lubricating oil can be supplied to the cam / roller contact portion P1 sufficiently and efficiently. Therefore, the lubricity in the cam / roller contact portion P1 can be improved without using an oil jet, and friction can be reduced.

  Further, since the lubricating oil is also supplied from the branching portion R23 of the oil passage R2 to the sliding portion P2 between the lifter 51 and the lifter guide 52, the lubricity in the sliding portion P2 can be improved, and the friction can be improved. Reduction can be achieved. Specifically, when the lifter 51 reciprocates, the flat portions 51a and 51a of the lifter 51 do not slide in contact with the lifter guide 52. However, the portions other than the flat portions 51a and 51a are in sliding contact with the lifter guide 52. There is a concern that the outer peripheral surface of the lifter 51 and the inner peripheral surface of the lifter guide 52 are worn. However, in portions other than the flat portions 51a and 51a of the lifter 51, the gap between the lifter 51 and the lifter guide 52 is narrow, making it difficult to supply the lubricating oil to the sliding portion P2 between the lifter 51 and the lifter guide 52.

  Therefore, in this example, an oil passage R <b> 2 is formed in the lifter guide 52 and the branch portion R <b> 23 communicates with the sliding portion P <b> 2 between the lifter 51 and the lifter guide 52. As a result, the lubricating oil can be supplied to the sliding portion P2 between the lifter 51 and the lifter guide 52 through the branch portion R23, and wear of the outer peripheral surface of the lifter 51 and the inner peripheral surface of the lifter guide 52 is reduced. be able to.

  In this case, the branch end R2c of the branch portion R23 is preferably provided in a portion of the lifter guide 52 where the reciprocating lifter 51 is always in sliding contact. That is, it is preferable to set the height position of the branch end R2c in the lifter guide 52 at a portion where the lifter 51 is always in sliding contact. Specifically, since the reciprocating area of the lifter 51 is determined according to the height of the cam nose 112 of the cam 111, the height of the cam nose 112 is determined from both ends (top dead center and bottom dead center) of the reciprocating area. The region excluding only the portion becomes a portion where the lifter 51 is always in sliding contact with the lifter guide 52. In the portion where the lifter 51 is always in sliding contact with the lifter guide 52, it is difficult to supply the lubricating oil. Therefore, by providing the branch end R2c of the branch portion R23 in that portion, the sliding portion between the lifter 51 and the lifter guide 52 is provided. P2 can be effectively lubricated.

  Next, a modification of the second embodiment will be described.

  As a modification of the second embodiment, the same as the modification of the first embodiment can be cited. Here, when it is set as the structure which provides the several oil passage R2 in the lifter guide 52, as shown in FIG. 7, it is possible to provide two oil passage R2, R2 in the lifter guide 52, for example. In this case, the two oil passages R2 and R2 are provided symmetrically around the axis of the lifter 51 with an angular interval of 180 °. The two oil passages R2 and R2 are provided at positions different from the flat portions 51a and 51a of the lifter 51 by 90 degrees around the axis. That is, the two oil passages R2 and R2 are provided so as to be orthogonal to the rotation axis direction of the roller 53, respectively.

  As described above, if the lifter guide 52 is provided with the two oil passages R2, R2, the lubricating oil is supplied to the cam / roller contact portion P1 not only from one side but from both sides. The lubricity in P1 can be further improved, which is effective. Further, in this example, the sliding portion P2 between the lifter 51 and the lifter guide 52 is divided into two parts by the flat portions 51a and 51a of the lifter 51, so that one oil passage R2 provided in the lifter guide 52 is provided. Therefore, the lubricating oil can be supplied only to one of the sliding portions P2. Therefore, as shown in FIG. 7, it is preferable to provide the lifter guide 52 with two oil passages R2 and R2 because the lubricating oil can be supplied equally to both of the sliding portions P2.

(Third embodiment)
Next, a third embodiment will be described with reference to FIG. The third embodiment is an improvement of the first embodiment. In the high-pressure fuel pump 1, the configuration of the oil passage R1 for sending the lubricating oil to the cam / roller contact portion P1 is the same as that of the first embodiment. Although it is the same as that of the case, the point which provided the check valve in this oil passage R1 differs from the case of the said 1st Example. Here, different points will be mainly described, and the same components (see FIGS. 3 and 4) as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof will be omitted.

  In this example, a check valve 61 as shown in FIG. 8 is provided in the middle of the oil passage R1 in order to prevent the lubricating oil from being sucked into the space 54 through the oil passage R1 when the lifter 51 is lifted. ing.

  Specifically, the check valve 61 includes a valve seat 61b inserted into the oil passage R1, a valve body (ball in FIG. 8) 61a disposed opposite to the valve seat 61b, a valve A compression coil spring 61c that urges the body 61a toward the valve seat 61b. When the pressure in the space 54 rises, the valve body 61a is separated from the valve seat 61b against the elastic force of the compression coil spring 61c, and the check valve 61 is opened. On the other hand, when the pressure in the space 54 decreases, the valve body 61a is seated on the valve seat 61b by the elastic force of the compression coil spring 61c, and the check valve 61 is closed.

  In the open state of the check valve 61, the lubricating oil in the space 54 is allowed to be forcibly discharged through the oil passage R1, so that in this example as well, as in the case of the first embodiment. The following effects can be obtained.

  In addition, in this example, the following effects can be obtained. That is, when the check valve 61 is not provided, when the lifter 51 is lifted, the pressure in the space 54 decreases, and the lubricating oil is sucked into the space 54 through the oil passage R1. At this time, the lubricating oil supplied to the cam / roller contact portion P1 through the oil passage R1 when the lifter 51 is lowered may be sucked. Therefore, in this example, a configuration in which the check valve 61 is provided in the middle of the oil passage R1 is adopted. Thus, in the closed state of the check valve 61, the lubricating oil is prevented from being sucked into the space 54 through the oil passage R1, so that the lubricating oil supplied to the cam / roller contact portion P1 is within the space 54. Can be prevented, and a decrease in lubricity at the cam / roller contact portion P1 can be suppressed.

  Next, a modification of the third embodiment will be described.

  As a modification of the third embodiment, the same as the modification of the first embodiment can be cited. Here, also when it is set as the structure which provides the several oil passage R1 in the lifter guide 52, it is preferable to provide the check valve 61 in each oil passage R1.

  Further, the configuration of the second embodiment can be combined with the configuration of the third embodiment. For example, as shown in FIG. 9, a check valve 61 is provided in a portion R21 on one end side of the oil passage R2. In this case, the check valve 61 is arranged upstream of the connecting end R2d where the branching portion R23 is branched in the portion R21 on the one end side. In this way, in the closed state of the check valve 61, the lubricating oil is prevented from being sucked into the space 54 through the oil passage R2, so that the check valve 61 is supplied to the sliding portion P2 between the lifter 51 and the lifter guide 52. In addition, it is possible to prevent the lubricating oil from being sucked into the space 54, and it is possible to suppress a decrease in lubricity at the sliding portion P2.

-Other embodiments-
The embodiment of the present invention has been described above. However, the embodiment shown here is an example and can be variously modified.

  (1) In the above, the high pressure fuel pump 1 is configured such that the plunger 23 and the lifter 51 are disposed above the pressurizing chamber 22, and the cam 111 is disposed further upward. The orientation of may be other orientations. Also in this case, since the lubricating oil in the space 54 is released to the outside through the oil passage R1, even if the lubricating oil in the space 54 is compressed by the reciprocating motion of the lifter 51, the drive torque is excessively increased. In addition to avoiding damage to the pump parts, the lubricity of the cam / roller contact portion P1 and the like can be improved.

  (2) In the above description, the lifter 51 is reciprocated by the rotation of the cam 111 attached to the intake camshaft 110. However, the lifter 51 is reciprocated by the rotation of the cam attached to the exhaust camshaft. Also good.

  (3) In the above, the lifter 51 is reciprocated by the cam 111 having the three cam noses 112, 112, 112. However, the lifter 51 is moved by the cams having other numbers of cam noses (for example, two cam noses). It may be configured to reciprocate.

  (4) The case where the present invention is applied to an in-cylinder direct injection type 6-cylinder gasoline engine mounted on an automobile has been described above. The present invention is not limited to this, and can be applied to, for example, a gasoline engine having any number of cylinders such as an in-cylinder direct injection four-cylinder gasoline engine. Further, the present invention is not limited to a gasoline engine, but can be applied to other internal combustion engines such as a diesel engine. Furthermore, the engine to which the present invention is applicable is not limited to an automobile engine.

It is a figure which shows typically an example of the fuel supply apparatus to which the high-pressure fuel pump of this invention is applied. It is a figure for demonstrating the opening / closing operation | movement of an electromagnetic spill valve. It is a longitudinal cross-sectional view which shows an example of the high pressure fuel pump of this invention. It is A arrow directional view of FIG. It is a figure which shows the high pressure fuel pump of the modification of 1st Example. It is a figure which shows the high pressure fuel pump of 2nd Example. It is a figure which shows the high pressure fuel pump of the modification of 2nd Example. It is a figure which shows the high pressure fuel pump of 3rd Example. It is a figure which shows the high pressure fuel pump of the modification of 3rd Example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 High pressure fuel pump 21 Cylinder 22 Pressurization chamber 23 Plunger 27 Compression coil spring 30 Electromagnetic spill valve 51 Lifter 52 Lifter guide 53 Roller 100 Fuel supply device 110 Intake camshaft 111 Cam P1 Cam / roller contact part R1 Oil passage

Claims (4)

A plunger inserted into the cylinder so as to be reciprocally slidable; a pressure chamber defined by the cylinder and the plunger; a lifter disposed within the lifter guide so as to be slidable back and forth; and the cam lifter A compression coil spring that presses against the outer peripheral surface side, the lifter moves with the rotation of the cam, and the plunger reciprocates. In a high-pressure fuel pump that repeatedly pressurizes and discharges fuel in the pressurizing chamber,
The lifter guide is formed with an oil passage for discharging the lubricant in the space surrounded by the lifter and the lifter guide to the outside as the lifter reciprocates due to the rotation of the cam.
A portion on the outside of the oil passage extends in a direction so that the lubricating oil discharged from the oil passage can be guided to a contact portion between the cam and a member in contact with the outer peripheral surface of the cam. And high pressure fuel pump. The oil passage is provided with a branching portion branched in the middle of the oil passage,
The high-pressure fuel pump according to claim 1, wherein a branch end of the branch portion communicates with a sliding portion between the lifter and the lifter guide.   The high-pressure fuel pump according to claim 2, wherein a branch end of the branch portion is provided at a portion of the lifter guide where the lifter is always in sliding contact.   The non-return valve which permits the outflow of the lubricating oil from the inside of the space and prevents the inflow of the lubricating oil into the space is provided in the oil passage. Item 4. The high-pressure fuel pump according to any one of Items 3 to 3.

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