JP2019132211A - Fuel pump assembly structure - Google Patents

Abstract

To prevent rotation of a tappet and prevent oil leakage.SOLUTION: A cam shaft housing 20 has an adapter insertion hole 22 penetrating therethrough in a vertical direction. An inner opening 23 of the adapter insertion hole 22 opens toward a supply pump driving cam. An adapter 30 has a cylindrical cylinder part 31 and a pin 37 fixed to the cylinder part 31 and is fixed to the cam shaft housing 20. The pin 37 has a protruding part 39 which protrudes to the radial inner side further than an inner peripheral surface 31b of the cylinder part 31. A slide groove part 61 linearly extending along the vertical direction is formed on an outer peripheral surface of a tappet 52 of a supply pump 50. The slide groove part 61 allows insertion of the protruding part 39 of the pin 37, engages with the protruding part 39, and allows reciprocation of the tappet 52. Engagement between the slide groove part 61 and the protruding part 39 of the pin 37 restricts rotational movement of the tappet 52 relative to the adapter 30.SELECTED DRAWING: Figure 6

Description

  The present disclosure relates to a fuel pump assembly structure.

  Patent Document 1 describes an engine provided with a high-pressure fuel pump. A valve operating chamber is formed between the cylinder head of the engine and the cam housing, and an intake cam shaft and an exhaust cam shaft are accommodated in the valve operating chamber. The exhaust camshaft is provided with a plurality of exhaust cams for raising and lowering the exhaust valve and one drive cam for driving the high-pressure fuel pump. A part of the cam housing constitutes a pump housing part which is a part of the high-pressure fuel pump. A guide hole facing the drive cam is formed in the pump housing portion, and a tappet is provided in the guide hole so as to be movable up and down. A guide hole is formed in the outer peripheral surface of the tappet. A boss portion is provided in the pump housing portion, and a bolt hole is formed in the boss portion. The tip of the bolt screwed into the bolt hole is inserted into the guide hole on the outer peripheral surface of the tappet, thereby preventing the tappet from rotating and tilting when the tappet advances and retreats.

Japanese Patent Laying-Open No. 2015-40492

  In the high-pressure fuel pump described in Patent Document 1, the bolt hole for screwing the bolt that stops the tappet is formed in the pump housing part that is a part of the cam housing of the engine. May leak from the bolt hole to the outside of the engine. In order to avoid this oil leakage, it is conceivable to provide a protrusion on the outer peripheral surface of the tappet and provide a groove on the inner peripheral surface of the guide hole of the pump housing part. In this case, the groove is formed inside the hole. Therefore, it is difficult to form the groove as compared with the case where the groove is formed on the outer peripheral surface of the tappet, and the work efficiency may be deteriorated and the processing cost may be increased.

  Therefore, an object of the present disclosure is to provide a fuel pump assembly structure capable of preventing oil leakage while preventing rotation of the tappet.

  In order to solve the above problems, a fuel pump assembly structure according to the present disclosure includes a camshaft housing, an adapter, and a fuel pump. The camshaft housing has an adapter insertion hole extending in a predetermined direction from the internal opening that opens toward the cam of the camshaft of the engine, and accommodates the camshaft therein. The adapter extends along the predetermined direction and is disposed in a cylindrical cylinder part in which at least a part of the adapter part is inserted into the adapter insertion hole of the camshaft housing, and in an area of the cylinder part inserted into the adapter insertion hole. And a protruding portion that protrudes radially inward from the inner peripheral surface of the cylinder portion, and is fixed to the camshaft housing. The fuel pump has a tappet that is slidably supported in the predetermined direction on the inner peripheral surface of the cylinder portion of the adapter while supporting a roller that contacts the cam. And the fuel is supplied to the engine side using the reciprocating motion of the tappet. On the outer peripheral surface of the tappet, there is formed a groove portion that extends linearly along the predetermined direction and that engages with the protruding portion while allowing the protruding portion of the adapter to be inserted. The engagement between the protruding portion of the adapter and the groove portion of the tappet allows the tappet to reciprocate along the predetermined direction and restricts the rotational movement of the tappet in the direction crossing the groove portion.

  In the above-described configuration, the protruding portion of the adapter protrudes radially inward from the inner peripheral surface of the cylinder portion, and the adapter protruding portion is inserted into the outer peripheral surface of the tappet of the fuel pump in a straight line along a predetermined direction. Grooves that are allowed to engage with the protrusions are formed. For this reason, by properly arranging the protrusion of the adapter and the groove of the tappet, when the tappet is inserted into the cylinder of the adapter, the rotation of the camshaft rotation shaft (cam rotation shaft) and the fuel pump roller The shafts can be easily positioned so as to be substantially parallel to each other.

  Further, the engagement between the protruding portion of the adapter and the groove portion of the tappet restricts the rotational movement of the tappet in the direction crossing the groove portion. For this reason, when the fuel pump is driven (when the tappet is reciprocated), the cam shaft and the rotation axis of the roller of the fuel pump set when the tappet is inserted into the cylinder portion of the adapter. It can be prevented that the direction of rotation (direction intersecting with the groove portion) is not substantially parallel, and seizure between the cam and the roller can be prevented.

  Moreover, the protrusion part of an adapter is arrange | positioned in the area | region inserted in the adapter insertion hole among cylinder parts. Therefore, for example, a pin insertion hole penetrating in the radial direction is provided in the cylinder portion of the adapter, and the pin is protruded by inserting the pin into the pin insertion hole and projecting radially inward from the inner peripheral surface of the cylinder portion. Since the pin insertion hole is located in the area of the cylinder part that is inserted into the adapter insertion hole of the camshaft housing, oil that flows out of the cylinder part from the pin insertion hole is camped. It can be retained in the shaft housing. Accordingly, oil can be prevented from flowing out of the camshaft housing.

  In addition, an adapter is provided between the camshaft housing and the fuel pump, and the inner peripheral surface of the cylinder portion of the adapter slidably supports the tappet, so even if the cylinder portion is damaged by the sliding of the tappet, the adapter This can be dealt with by replacing the fuel pump, and unlike the case where the fuel pump is directly attached to the camshaft housing, there is no need to replace the camshaft housing.

  According to the present disclosure, oil leakage can be prevented while preventing the tappet from rotating.

1 is a schematic view of an engine to which a fuel pump assembly structure according to an embodiment of the present invention is applied. It is the schematic which looked at FIG. 1 from the arrow II direction. It is a schematic sectional drawing of the principal part of a fuel pump assembly | attachment structure. It is an external appearance perspective view of an adapter. It is an enlarged view of the principal part of a supply pump. It is sectional drawing which shows the engagement state of a pin and a slide groove part.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In the following description, the vertical direction corresponds to the vertical direction in FIGS. In each figure, CL1 indicates the rotation axis of the crankshaft 8, CL2 indicates the rotation axis of the camshaft 13, and CL3 indicates the rotation axis of the tappet roller 51 of the supply pump 50.

  As shown in FIGS. 1 and 2, the fuel pump assembly structure according to the present embodiment includes, for example, a supply pump (fuel pump) of a diesel engine 1 (hereinafter simply referred to as the engine 1) having a common rail fuel injection system. Applies to 50 assembly structures. In the common rail fuel injection system, the fuel in the fuel tank 2 is supplied to the supply pump 50 side by the feed pump 3, the fuel is pressurized by the supply pump 50 and supplied to the common rail 4, and the high pressure pressurized by the supply pump 50 is supplied. Are stored in the common rail 4, and a plurality (four in this embodiment) of the high-pressure fuel stored in the common rail 4 to a plurality of (four in the present embodiment) combustion chambers 6 of the engine 1. To spray. The fuel injected from the injector 5 into the combustion chamber 6 is ignited and burned by the high-temperature air compressed by the piston 7 in the combustion chamber 6, and the gas expanded by this combustion pushes down the piston 7 to The crankshaft 8 is rotated. In FIG. 2, only one combustion chamber 6 is shown.

  The engine 1 includes an intake valve 11 that controls intake air to the combustion chamber 6, an exhaust valve 12 that controls exhaust gas from the combustion chamber 6, a feed pump 3, and a camshaft 13 for driving a supply pump 50. The cylinder block 1a of the engine 1 supports the camshaft 13 rotatably. A shaft housing space 21 (see FIG. 3) for housing the camshaft 13 is defined inside the cylinder block 1a. That is, a part of the cylinder block 1a functions as a camshaft housing 20 (see FIG. 3) that defines the shaft housing space 21. The intake valve 11 and the exhaust valve 12 are connected to the push rod 16 via the arm 15 and are driven by the rotation of the camshaft 13. In FIG. 2, the arm 15 and the push rod 16 on the intake valve 11 side are shown, and the illustration of the arm 15 and the push rod 16 on the exhaust valve 12 side is omitted.

  As shown in FIGS. 1 to 3, the camshaft 13 is a rod-like member, and integrally includes a plurality of cams, and is rotatably supported by the cylinder block 1 a of the engine 1. The plurality of cams include a plurality of intake valve drive cams 17, a plurality of exhaust valve drive cams 18 (only one exhaust valve drive cam 18 is shown in FIG. 3), and a feed pump drive cam 19. And a supply pump drive cam (cam) 14. The camshaft 13 has a rotation axis CL2 extending in the axial direction (extending direction) of the camshaft 13, and is arranged so that the rotation axis CL2 of the camshaft 13 is substantially parallel to the rotation axis CL1 of the crankshaft 8. . An input gear 9 is fixedly provided at an end portion on one end side of the camshaft 13. The input gear 9 of the camshaft 13 is connected to the crankshaft 8 via a gear or a chain. By this connection, a force for rotating the camshaft 13 is input from the crankshaft 8 to the input gear 9 of the camshaft 13, and the camshaft 13 rotates as the crankshaft 8 rotates. The tip of the push rod 16 on the intake valve 11 side is in contact with the intake valve drive cam 17, and the tip of the push rod 16 on the exhaust valve 12 side is in contact with the exhaust valve drive cam 18. The tappet roller (not shown) of the feed pump 3 comes into contact with the supply pump drive cam 14, and a tappet roller (roller) 51, which will be described later, of the supply pump 50 comes into contact. The intake valve drive cam 17 drives the intake valve 11, the exhaust valve drive cam 18 drives the exhaust valve 12, the feed pump drive cam 19 drives the feed pump 3, and the supply pump drive cam 14 drives the supply pump 50. To do.

  As shown in FIG. 3, the fuel pump assembly structure according to this embodiment includes a camshaft housing 20, an adapter 30, and a supply pump 50 of the engine 1.

  The camshaft housing 20 has an adapter insertion hole 22 penetrating along the vertical direction (predetermined direction), and defines a shaft housing space 21. The adapter insertion hole 22 communicates the shaft housing space 21 with the outside of the camshaft housing 20. The adapter insertion hole 22 extends in a direction crossing the rotation axis CL2 of the camshaft 13. An opening 23 on the shaft housing space 21 side of the adapter insertion hole 22 (hereinafter referred to as an internal opening 23) is disposed at a position spaced upward from the supply pump drive cam 14 of the camshaft 13 housed in the shaft housing space 21. , Opening toward the supply pump drive cam 14.

  As shown in FIGS. 3 and 4, the adapter 30 includes a cylindrical cylinder portion 31 that extends in the vertical direction, a flange-like flange portion 32 that extends radially outward from the upper end portion of the cylinder portion 31, and the cylinder portion 31. The pin 37 is fixed to the camshaft housing 20.

  The cylinder part 31 is inserted into the adapter insertion hole 22 of the camshaft housing 20 from above. With the cylinder portion 31 inserted into the adapter insertion hole 22 of the camshaft housing 20 from above, the flange portion 32 is disposed outside the camshaft housing 20, and the upper surface of the camshaft housing 20 around the adapter insertion hole 22 It is fastened and fixed to. A seal member (not shown) such as a gasket is interposed between the flange portion 32 and the upper surface of the camshaft housing 20 around the adapter insertion hole 22. The cylinder portion 31 has a pump insertion hole 35 that communicates the upper end opening 33 and the lower end opening 34 and extends linearly in the vertical direction. The direction in which the axis of the pump insertion hole 35 extends (the predetermined direction) is a direction orthogonal to the rotation axis CL2 of the camshaft 13. The lower end opening 34 is disposed at a position spaced upward from the supply pump drive cam 14 of the camshaft 13 accommodated in the shaft accommodation space 21 and opens toward the supply pump drive cam 14. In a region 36 of the cylinder portion 31 that is inserted into the adapter insertion hole 22 of the camshaft housing 20, a pin is inserted that penetrates the cylinder portion 31 in the radial direction (in the present embodiment, the direction orthogonal to the axis of the cylinder portion 31). A hole 38 is formed. The pin insertion hole 38 extends along a direction orthogonal to the rotation axis CL2 of the camshaft 13 in a top view. The position where the pin insertion hole 38 is provided is included in a range in which the later-described tappet 52 of the supply pump 50 slides in the region 36 of the cylinder portion 31.

  The pin 37 is a rod body that extends along the pin insertion hole 38 of the cylinder part 31, and is pressed into the pin insertion hole 38 and fixed to the cylinder part 31. That is, the pin 37 extends along a direction orthogonal to the rotation axis CL2 of the camshaft 13 in a top view. In a state where the pin 37 is fixed to the cylinder part 31, the outer end of the radial pin 37 of the cylinder part 31 is disposed on substantially the same surface as the outer peripheral surface 31 a of the cylinder part 31. The inner end of the pin 37 is disposed on the radially inner side with respect to the inner peripheral surface 31 b of the cylinder portion 31. That is, the pin 37 has a protruding portion 39 (see FIG. 6) that protrudes radially inward from the inner peripheral surface 31 b of the cylinder portion 31 in a state of being fixed to the cylinder portion 31. The protruding portion 39 of the pin 37 protrudes along a direction orthogonal to the rotation axis CL2 of the camshaft 13 in a top view.

  As shown in FIG. 3, the supply pump 50 is a piston type pump having a pump main body 53, a plunger 54, a tappet 52, and a tappet roller 51. This is converted into motion, and the plunger 54 in the pump body 53 is reciprocated by the reciprocating motion of the tappet 52 to supply the fuel supplied from the feed pump 3 to the common rail 4 (see FIG. 1) side. The supply pump 50 is fixed to the camshaft housing 20 via the adapter 30.

  As shown in FIGS. 3 and 5, the tappet 52 is formed in a substantially cylindrical shape, and its outer peripheral surface 52 c slides along the inner peripheral surface 31 b of the cylinder portion 31 of the adapter 30, and moves up and down in the cylinder portion 31. Move back and forth. The sliding range 62 of the tappet 52 (range of reciprocating movement) is such that the lower end 52a of the tappet 52 at the top dead center (position indicated by a two-dot chain line in FIG. 5) is at the bottom dead center (position indicated by a solid line in FIG. 5). It is set to be positioned below the upper end 52b of the tappet 52. That is, the sliding range 62 of the tappet 52 has an area 63 where the tappet 52 always exists when the tappet 52 reciprocates (between the lower end 52a of the tappet 52 at the top dead center and the upper end 52b of the tappet 52 at the bottom dead center). An area (hereinafter referred to as an overlapping area 63) exists. The pin insertion hole 38 (see FIG. 4) of the cylinder part 31 is located within the sliding range 62 of the tappet 52 in the above-described area 36 of the cylinder part 31 (area 36 inserted into the adapter insertion hole 22 of the camshaft housing 20). It is formed at a height position (position indicated by a one-dot chain line 64 in FIG. 5) included in the overlapping region 63, and the pin 37 is also a height position (one-dot chain line in FIG. 5) included in the overlapping region 63 of the sliding range 62 of the tappet 52. 64). A wall portion 60 that partitions the inner diameter portion into an upper region and a lower region is provided at the inner diameter portion of the tappet 52.

  As shown in FIGS. 5 and 6, the outer peripheral surface 52c of the tappet 52 is formed with a slide groove portion (groove portion) 61 that extends linearly along the vertical direction while being recessed radially inward from the outer peripheral surface 52c. . The slide groove portion 61 extends downward from a predetermined height position below the upper end 52 b of the tappet 52 and is opened downward from the lower end 52 a of the tappet 52. The slide groove 61 is formed in a size that allows the protrusion 39 of the pin 37 of the adapter 30 to be inserted and engages with the protrusion 39 of the pin 37. The width of the slide groove 61 (the length in the circumferential direction of the tappet 52) is such that the tappet 52 rotates relative to the adapter 30 when the slide groove 61 of the tappet 52 and the protrusion 39 of the pin 37 of the adapter 30 are engaged. It is set slightly longer than the diameter of the pin 37 so that (the movement of the tappet 52 in the circumferential direction) is restricted. The length (vertical length) of the slide groove 61 is longer than the diameter of the pin 37, and the top dead center and bottom dead of the tappet 52 in a state where the protrusion 39 of the pin 37 is inserted into the slide groove 61. It is set to a length that allows movement between points. That is, the upper end of the slide groove 61 is set so as to be positioned above the height position 64 of the pin 37 in a state where the tappet 52 is at the bottom dead center, and the lower end of the slide groove 61 (in this embodiment, the tappet 52 The lower end 52a) of the pin 37 is set to be positioned below the height position 64 of the pin 37 in a state where the tappet 52 is at the top dead center. A tappet roller 51 is disposed in a region below the wall portion 60 of the inner diameter portion of the tappet 52.

  As shown in FIG. 3, the tappet roller 51 is rotatably supported by a pair of roller support portions 65 extending downward from the tappet 52 via a shaft bar 66. The pair of roller support portions 65 are opposed to each other in the direction in which the rotation axis CL2 of the camshaft 13 extends, and the shaft rod 66 is located between the pair of roller support portions 65 along the rotation axis CL2 of the camshaft 13. Extends linearly. That is, the direction in which the shaft bar 66 extends (the direction in which the rotation axis CL3 of the tappet roller 51 extends) is set to be substantially parallel to the rotation axis CL2 of the camshaft 13 and orthogonal to the direction in which the slide groove 61 is recessed. Is done. The tappet roller 51 abuts on the supply pump drive cam 14 while being biased toward the lower supply pump drive cam 14. When the supply pump drive cam 14 is rotated by the rotation of the camshaft 13, the tappet roller 51 rotates around the rotation axis CL3, and the tappet roller 51, the tappet 52, and the plunger 54 reciprocate along the vertical direction. Pressurizes the fuel in the pump chamber of the pump body 53 and supplies it to the common rail 4 side. That is, the supply pump 50 converts the rotational motion of the camshaft 13 into the reciprocating motion of the tappet 52, reciprocates the plunger 54 using the reciprocating motion of the tappet 52, pressurizes the fuel, and supplies the fuel to the common rail 4. To do. Oil is supplied to the outer peripheral surface 52c of the tappet 52 and the tappet roller 51 of the supply pump 50 from an oil passage (not shown).

  When the supply pump 50 is assembled to the engine 1, first, the tappet 52 supporting the tappet roller 51 is first inserted into the pump insertion hole 35 of the adapter 30 from above and from the lower end of the slide groove 61 of the tappet 52. The pin 37 of the adapter 30 is inserted and engaged. Next, the plunger 54 is inserted into the pump insertion hole 35 of the adapter 30 from above, and the flange portion 53a of the pump main body 53 is fastened and fixed to the adapter 30 so that the supply pump 50 and the adapter 30 are unitized. Finally, the cylinder portion 31 of the adapter 30 unitized with the supply pump 50 is inserted into the adapter insertion hole 22 of the camshaft housing 20 of the engine 1 from above, and the flange portion 32 of the adapter 30 is inserted into the camshaft housing 20. Fasten and fix against. The method for assembling the supply pump 50 to the engine 1 is not limited to the above. For example, first, the adapter 30 is fastened and fixed to the camshaft housing 20, and then the supply pump is fixed to the adapter 30. The method of fixing 50 may be used.

  In the fuel pump assembly structure configured as described above, the protruding portion 39 of the pin 37 of the adapter 30 protrudes radially inward from the inner peripheral surface 31b of the cylinder portion 31, and the outer peripheral surface 52c of the tappet 52 of the supply pump 50. It engages with the slide groove 61 formed in the. The direction in which the rotation axis CL3 of the tappet roller 51 extends is set substantially parallel to the rotation axis CL2 of the camshaft 13. That is, with the protrusion 39 on the adapter 30 side and the slide groove 61 on the supply pump 50 side engaged, the direction of the rotation axis CL3 of the tappet roller 51 is the desired direction (in this embodiment, the camshaft 13 A protrusion 39 on the adapter 30 side and a slide groove 61 on the supply pump 50 side are arranged so as to be in a direction substantially parallel to the rotation axis CL2. Therefore, when the supply pump 50 is attached to the adapter 30, the rotation groove CL 2 of the camshaft 13 and the tappet roller 51 of the supply pump 50 are engaged by engaging the slide groove 61 of the tappet 52 and the pin 37 of the adapter 30. The rotation axis CL3 can be easily positioned so as to be substantially parallel to each other.

  Further, the engagement between the slide groove portion 61 of the tappet 52 and the protruding portion 39 of the pin 37 of the adapter 30 is the rotational movement of the tappet 52 relative to the adapter 30 (movement of the tappet 52 in the circumferential direction (direction intersecting the slide groove portion 61)). ). Therefore, the substantially parallel positional relationship between the rotation axis CL2 of the camshaft 13 and the rotation axis CL3 of the tappet roller 51 of the supply pump 50 changes in the rotation direction when the supply pump 50 is driven (when the tappet 52 reciprocates). Thus, it can be prevented that the supply pump drive cam 14 and the tappet roller 51 are burned.

  Further, the protruding portion 39 of the pin 37 of the adapter 30 is arranged in a region 36 of the cylinder portion 31 that is inserted into the adapter insertion hole 22 of the camshaft housing 20. For this reason, even if oil flows out from the pin insertion hole 38 of the adapter 30 to the outside of the cylinder portion 31, the oil does not flow out of the engine 1 (outside of the camshaft housing 20), and the oil flows to the camshaft housing. 20 can be retained within the camshaft housing 20 to prevent the oil from flowing out of the camshaft housing 20.

  Further, the adapter 30 is provided between the camshaft housing 20 and the supply pump 50, and the inner peripheral surface 31b of the cylinder portion 31 of the adapter 30 supports the tappet 52 in a slidable manner. Even if the inner peripheral surface 31b of the portion 31 is damaged, it can be dealt with by replacing the adapter 30, and it is necessary to replace the camshaft housing 20, unlike the case where the supply pump 50 is directly attached to the camshaft housing 20. There is no.

  In the present embodiment, a part of the cylinder block 1a of the engine 1 is made to function as the camshaft housing 20, but the camshaft housing 20 is not limited to this, for example, the inside of the cylinder head of the engine 1 Alternatively, the camshaft 13 may be arranged so that a part of the cylinder head of the engine 1 functions as the camshaft housing 20.

  In the present embodiment, the direction in which the adapter insertion hole 22 of the camshaft housing 20 and the pump insertion hole 35 of the adapter 30 extend (the predetermined direction) is the vertical direction, but the predetermined direction is limited to this. Instead, any other direction may be used as long as the direction is orthogonal to the rotation axis CL2 of the camshaft 13.

  In the present embodiment, the camshaft 13 having a plurality of cams (a plurality of intake valve drive cams 17, a plurality of exhaust valve drive cams 18, a feed pump drive cam 19, and a supply pump drive cam 14) is provided. The camshaft 13 is not limited to this, and any camshaft 13 having at least a supply pump drive cam (cam) 14 may be used.

  Further, in the present embodiment, a pin insertion hole 38 is provided in the cylinder portion 31 of the adapter 30, the pin 37 is press-fitted into the pin insertion hole 38, and the pin 37 protrudes radially inward from the inner peripheral surface 31 b of the cylinder portion 31. Although the protrusion part 39 was formed by making it, the protrusion part 39 is not limited to this. For example, a bolt insertion hole is provided in the cylinder portion 31, a bolt is screwed into the bolt insertion hole from the outside, and the tip end side of the bolt protrudes radially inward from the inner peripheral surface 31 b of the cylinder portion 31. A part may be formed. Alternatively, a protruding portion that protrudes radially inward from the inner peripheral surface 31 b of the cylinder portion 31 may be integrally formed with the cylinder portion 31.

  In the present embodiment, the protruding portion 39 of the pin 37 protrudes in a direction orthogonal to the rotation axis CL2 of the camshaft 13 when viewed from above. As described above, in the present embodiment, the protruding portion 39 is provided at the portion of the cylinder portion 31 that intersects the imaginary line orthogonal to the rotation axis CL2 of the camshaft 13 in the top view, but the position where the protruding portion 39 is provided is It is not limited to this, The protrusion part 39 can be provided in the arbitrary positions of the circumferential direction of the cylinder part 31. FIG. Similarly to the protruding portion 39 of the pin 37, the slide groove portion 61 provided in the tappet 52 can also be provided at an arbitrary position in the circumferential direction of the outer peripheral surface 52 c of the tappet 52. That is, with the protrusion 39 on the adapter 30 side and the slide groove 61 on the supply pump 50 side engaged, the direction of the rotation axis CL3 of the tappet roller 51 is the desired direction (in this embodiment, the camshaft 13 The protruding portion 39 on the adapter 30 side and the slide groove portion 61 on the supply pump 50 side can be arranged so as to be in a direction substantially parallel to the rotation axis CL2.

  In the present embodiment, the lower side of the slide groove 61 is opened downward from the lower end 52a of the tappet 52. However, the present invention is not limited to this, and the slide groove 61 is a protrusion of the pin 37 on the adapter 30 side. What is necessary is just to have the length which accept | permits the reciprocation of the up-down direction of the tappet 52 with respect to the adapter 30 in the state which 39 was inserted and mutually engaged.

  In the present embodiment, the fuel pump assembly structure according to the present disclosure is applied to the assembly structure of the supply pump 50 that is a high-pressure fuel pump. However, the present invention is not limited to this. You may apply to an assembly structure.

  As mentioned above, although this indication was demonstrated based on the said embodiment, this indication is not limited to the content of the said embodiment, Of course, it can change suitably in the range which does not deviate from this indication. That is, it is needless to say that other embodiments, examples, operation techniques, and the like made by those skilled in the art based on this embodiment are all included in the scope of the present disclosure.

  For example, in the above embodiment, the fuel pump assembly structure according to the present disclosure is applied to the diesel engine 1, but may be applied to a gasoline engine. Further, the present invention may be applied to an engine that does not include a common rail fuel injection system.

1: Engine 13: Camshaft 14: Supply pump drive cam (cam)
20: Camshaft housing 22: Adapter insertion hole 23: Internal opening 30: Adapter 31: Cylinder part 31b: Inner peripheral surface 36 of the cylinder part: Area (partial area of the cylinder part)
50: Supply pump (fuel pump)
51: Tappet roller (roller)
52: Tappet 52c: Outer peripheral surface of tappet 61: Slide groove (groove)

Claims (1)

A camshaft housing having an adapter insertion hole extending in a predetermined direction from an internal opening that opens toward a cam of an engine camshaft to the outside, and housing the camshaft therein;
A cylindrical cylinder part extending along the predetermined direction and having at least a part of the area inserted into the adapter insertion hole of the camshaft housing, and an area of the cylinder part inserted into the adapter insertion hole. An adapter that is protruded radially inward from an inner peripheral surface of the cylinder portion and is fixed to the camshaft housing;
A tappet that is slidably supported in the predetermined direction on the inner peripheral surface of the cylinder portion of the adapter in a state where a roller that contacts the cam of the cam shaft is supported; A fuel pump that converts the reciprocating motion of the tappet along a direction and supplies fuel to the engine side using the reciprocating motion of the tappet,
On the outer peripheral surface of the tappet, a groove that extends linearly along the predetermined direction and that engages with the protrusion while allowing insertion of the protrusion of the adapter is formed.
The engagement between the protruding portion of the adapter and the groove portion of the tappet allows the tappet to reciprocate along the predetermined direction and restricts the rotational movement of the tappet in a direction crossing the groove portion. A fuel pump assembly structure characterized by that.

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