Roller Lifter

Abstract

To provide a roller lifter which can improve whirl-stop reliability while achieving favorable manufacturability.SOLUTION: A roller lifter 20 comprises a lifter main body 30, a shaft 70, a roller 40 and an attachment member 50. The lifter main body 30 is formed into a cylindrical shape which can reciprocate in a hole 12 of a housing 11. The shaft 70 is supported to a peripheral wall 31 of the lifter main body 30 at both end parts in an axial direction. The roller 40 is arranged in the lifter main body 30 while being rotatably supported to the shaft 70. The attachment member 50 is arranged in the lifter main body 30. The lifter main body 30 has a penetration hole 37 penetrating the peripheral wall 31 in a radial direction. The attachment member 50 has a holding part 52 and a whirl-stop part 51. The holding part 52 is held by the shaft 70 at an end face side of the roller 40. The whirl-stop part 51 penetrates the penetration hole 37 while extending from the holding part 52, and protrudes to the outside from an external peripheral face of the peripheral wall 31.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to a roller lifter. [Background technology]

[0002] Patent Documents 1 and 2 disclose a tappet having a cylindrical main body and an anti-rotation member attached to the main body. The tappet is disposed in a guide hole in a housing of an internal combustion engine or the like, and slides back and forth within the guide hole by the drive of a cam. The anti-rotation member is a structure for preventing rotation within the guide hole in a tappet (roller lifter) equipped with a roller, thereby ensuring parallelism of the roller's rotation axis relative to the cam's rotation axis. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] German Patent Application Publication No. 102004036106 [Patent Document 2] US Patent Application Publication No. 2010 / 0294219 Summary of the Invention [Problem to be solved by the invention]

[0004] In the case of Patent Document 1, the anti-rotation member is press-fitted into a window-shaped opening formed in the main body, and is therefore firmly fixed to the main body. However, in this case, it is necessary to prevent deformation of the main body due to press-fitting the anti-rotation member, and a certain degree of dimensional accuracy is required for both the anti-rotation member and the opening on the main body side. In the case of Patent Document 2, the anti-rotation member is disposed inside the main body and can be easily attached by inserting the anti-rotation member into a recess formed in the main body. However, since the anti-rotation member is only held against the inner circumferential surface of the tappet main body by a spring-like arm, there is a concern that it may fall off.

[0005] Therefore, an object of the present disclosure is to provide a roller lifter that can improve the reliability of the anti-rotation function while achieving good manufacturability. [Means for solving the problem]

[0006] The roller lifter of the present disclosure comprises a cylindrical lifter body capable of sliding back and forth within a hole in a housing, a shaft whose both axial ends are supported by the peripheral wall of the lifter body, a roller rotatably supported on the shaft, and an attachment member arranged within the lifter body, wherein the lifter body has a through hole that passes through the peripheral wall, and the attachment member has a retaining portion that is held by the shaft on the end face side of the roller, and a rotation prevention portion that extends from the retaining portion, passes through the through hole, and protrudes outward from the outer circumferential surface of the peripheral wall. [Effects of the Invention]

[0007] According to the present disclosure, a rotation prevention portion can be easily provided without requiring strict dimensional accuracy, and a mounting member having a rotation prevention portion can be stably disposed within a lifter body. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a cross-sectional view illustrating a part of a fuel supply device including a roller lifter according to a first embodiment. [Figure 2] FIG. 2 is a side view showing the roller lifter according to the first embodiment. [Figure 3] FIG. 3 is a bottom view showing the roller lifter according to the first embodiment. [Figure 4] FIG. 4 is a side view showing the mounting member according to the first embodiment. [Figure 5] FIG. 5 is a bottom view showing the roller lifter according to the second embodiment. [Figure 6] FIG. 6 is a side view showing the mounting member according to the second embodiment. [Figure 7] FIG. 7 is a diagram illustrating a state in which the mounting member is in the second position in the roller lifter according to the second embodiment. [Figure 8] FIG. 8 is a diagram illustrating a state in which the mounting member is in the first position in the roller lifter according to the second embodiment. [Figure 9] FIG. 9 is an enlarged cross-sectional view of a main part showing a roller lifter according to another embodiment. [Figure 10] FIG. 10 is a side view showing a mounting member according to another embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0009] [Description of the embodiments of the present disclosure] A preferred embodiment of the present disclosure is as follows.

[0010] The mounting member may have a connecting portion that connects the holding portion and the anti-rotation portion, and may be integrally formed from a single plate material. In this case, the mounting member can be easily formed, and better manufacturability of the roller lifter can be achieved.

[0011] The peripheral wall may have a pair of opposing walls that are parallel to each other in a radial direction of the peripheral wall and a pair of arc-shaped walls that are parallel to each other in the radial direction of the peripheral wall, the through-holes may be formed in one of the pair of arc-shaped walls, the retaining portions may be arranged in pairs along each of the pair of opposing walls, and the connecting portion may be arranged along an inner circumferential surface of one of the pair of arc-shaped walls. In this case, the mounting member can be stably arranged on the lifter body.

[0012] The mounting member may be movable between a first position where the anti-rotation portion protrudes outward from the outer circumferential surface of the peripheral wall and a second position where the anti-rotation portion is moved inward of the peripheral wall from the first position. In this case, the mounting member can be easily attached to the lifter body.

[0013] The shaft may have a circumferential groove formed on its outer surface along the circumferential direction of the shaft, the retaining portion may have a retaining hole formed therein through which the shaft passes, and when the mounting member is in the first position, the peripheral edge of the retaining hole in the retaining portion may be disposed within the circumferential groove. In this case, the mounting member also functions as a retainer for the shaft. This eliminates the need for a separate shaft retaining function, such as crimping, thereby achieving even better manufacturability.

[0014] The mounting member may preferably have a restricting portion that restricts movement from the first position to the second position. In this case, the mounting member can be suitably held in the first position. This effectively prevents the anti-rotation portion from falling out of the through-hole, further improving the reliability of the anti-rotation portion. Furthermore, since the retaining portion can be effectively prevented from falling out of the circumferential groove, the shaft can be effectively held in a locked state.

[0015] The restricting portion may be provided so as to protrude from the anti-rotation portion and engage with an opening edge of the through hole on the outer peripheral surface of the peripheral wall. In this case, the restricting portion can be provided with a simple configuration, which allows for even better manufacturability.

[0016] The anti-rotation portion may be in contact with the inner surface of the through hole while applying an elastic force to the anti-rotation portion, thereby suitably suppressing rattles within the through hole.

[0017] [Details of the embodiments of the present disclosure] An embodiment of the present disclosure will be described below with reference to the drawings. For convenience, in the following description, the direction of reciprocating motion of a roller lifter (described later) is defined as the up-down direction. That is, the up-down direction is defined as the direction shown in Figures 1, 2, 4, 6 to 8, and 10. However, the directions defined here do not limit the installation direction of a roller lifter according to the present disclosure.

[0018] Example 1 A roller lifter 20 according to Example 1 of this embodiment will be described with reference to Figures 1 to 4. The roller lifter 20 is configured as a pump lifter used in a fuel supply device 10 of an internal combustion engine shown in Figure 1, for example. The fuel supply device 10, although not shown in detail, supplies fuel adjusted to high pressure by the roller lifter 20 to a combustion chamber of the engine, not shown. The roller lifter 20 is incorporated into a housing 11 of a cylinder head.

[0019] 1, a hole 12 is formed in the housing 11. The hole 12 has a generally circular cross section and extends in the vertical direction. A roller lifter 20 is inserted into the hole 12 so as to be slidable back and forth in the vertical direction.

[0020] A hole 14 having a circular cross section and a smaller diameter than hole 12 is provided in the housing 11 at the upper end of hole 12 so as to penetrate in the vertical direction. A plunger 15 is inserted into hole 14 so as to be able to slide back and forth in the vertical direction. The upper end of plunger 15 is arranged so as to be able to advance and retreat in a pressure chamber (not shown) that communicates with the upper end of hole 14. When the upper end of plunger 15 advances into the pressure chamber, the fuel in the pressure chamber is pressurized.

[0021] A guide groove 16 is formed in the housing 11 and extends vertically along the hole 12. The lower end of the guide groove 16 is open. A rotation prevention portion 51 of the mounting member 50 (described later) is inserted into the guide groove 16 so as to be movable vertically.

[0022] As shown in Figures 2 and 3, the roller lifter 20 comprises a lifter body 30, a shaft 70, a roller 40, and an attachment member 50. The lifter body 30 supports the roller 40 and is configured to move back and forth in the vertical direction in response to the rotation of a cam 60, as described below. The lifter body 30 is made of, for example, a metal material with excellent wear resistance. The lifter body 30 comprises a peripheral wall 31 and a partition wall 32. The peripheral wall 31 is approximately cylindrical. The peripheral wall 31 forms the outer shell of the lifter body 30. The peripheral wall 31 is approximately cylindrical and extends in the vertical direction. The outer peripheral surface of the peripheral wall 31, except for the opposing wall 34, which will be described later, is arranged along the inner peripheral surface of the hole 12 and is in sliding contact with the inner peripheral surface of the hole 12.

[0023] 2 and 3, the peripheral wall 31 has a cylindrical wall 33, a pair of opposing walls 34, a pair of arc-shaped walls 35 and 36, and a through hole 37. The cylindrical wall 33 has a cylindrical shape and constitutes the upper end side of the peripheral wall 31. The pair of opposing walls 34 and the pair of arc-shaped walls 35 respectively constitute the lower end side of the peripheral wall 31. The outer peripheral surface of the cylindrical wall 33 and the outer peripheral surfaces of the pair of arc-shaped walls 35 each constitute the outer peripheral surface of the peripheral wall 31 and come into sliding contact with the inner peripheral surface of the hole 12.

[0024] As shown in Figure 3, the pair of opposing walls 34 are flat plates facing each other in parallel in the radial direction of the peripheral wall 31. Each opposing wall 34 is formed by recessing the peripheral wall 31 radially inward. The pair of opposing walls 34 support both ends of the shaft 70. Each of the pair of opposing walls 34 defines a shaft hole 38. The pair of shaft holes 38 are formed coaxially in the radial direction of the peripheral wall 31. Both ends of the shaft 70, which will be described later, are inserted into the pair of shaft holes 38.

[0025] As shown in FIG. 3 , the pair of arc-shaped walls 35, 36 are disposed opposite each other in a direction perpendicular to the opposing direction of the pair of opposing walls 34. The pair of arc-shaped walls 35, 36 are disposed curvedly between the pair of opposing walls 34. The outer peripheral surfaces of the pair of arc-shaped walls 35, 36 are slidable along the inner peripheral surface of the hole 12. Of the pair of arc-shaped walls 35, 36, the inner peripheral surface of one arc-shaped wall 35 has a flat shape that extends along the opposing direction of the pair of opposing walls 34. The inner peripheral surface of the other arc-shaped wall 36 has an arc shape that follows the arc shape of the outer peripheral surfaces. Each of the arc-shaped walls 35, 36 is connected to the pair of opposing walls 34 at both circumferential ends.

[0026] The through hole 37 is formed penetrating the peripheral wall 31 in the radial direction (thickness direction). Specifically, the through hole 37 is formed in a portion of the peripheral wall 31 below the partition wall 32. More specifically, the through hole 37 is formed in the pair of opposing walls 34, which are portions of the peripheral wall 31 below the partition wall 32, and in the arc-shaped wall 36, which is formed by an arc-shaped inner circumferential surface, of the pair of arc-shaped walls 35, 36. A rotation prevention portion 51 (described later) of the mounting member 50 is passed through the through hole 37. The through hole 37 is formed in a rectangular hole. In this embodiment, the through hole 37 is formed in the circumferential center of the arc-shaped wall 36. The through hole 37 is also formed in the upper end of the arc-shaped wall 36. When viewed over the entire height of the peripheral wall 31, the through hole 37 is formed in the axial center of the peripheral wall 31.

[0027] The outer peripheral surface of the roller 40 is disposed so as to come into contact with the cam 60. As shown in Fig. 1, the cam 60 has a substantially rectangular shape and is mounted on a camshaft 61. In this embodiment, the roller 40 is rotatably supported on the shaft 70 via a needle bearing 72, as shown in Fig. 2. The roller 40 may also be directly supported on the shaft 70 without using a needle bearing or the like.

[0028] The shaft 70 is supported by the lifter body 30 at the pair of opposing walls 34. As shown in Fig. 3, both ends of the shaft 70 extend in the axial direction and pass through axial holes 38 formed in the pair of opposing walls 34. In the present embodiment, the shaft 70 is fixed to the pair of opposing walls 34 by caulking or the like. Note that the shaft 70 may also be supported by the pair of opposing walls 34 so as to be rotatable within the axial holes 38.

[0029] 1 and 2, the partition wall 32 is formed in the shape of a flat plate extending radially within the peripheral wall 31. The outer periphery of the partition wall 32 is integrally connected to the inner periphery of the peripheral wall 31. The internal space of the lifter body 30 is divided into upper and lower spaces by the partition wall 32. Below the partition wall 32 in the lifter body 30, a roller 40 is housed, which is arranged between both opposing walls 34.

[0030] The lifter body 30 is extended in the axial direction as far as possible within a range that is out of the rotational path of the cam 60 located below. In other words, the vertical sliding length of the peripheral wall 31 is ensured to be sufficiently long, and the lifter body 30 is structured so as not to tilt within the hole 12.

[0031] As shown in FIG. 1 , the lower end of the plunger 15, a retainer 81, and an urging member 82 are housed above the partition wall 32 within the lifter body 30. The retainer 81 is disk-shaped and extends radially along the peripheral wall 31, with the lower end of the plunger 15 engaged and fixed to its center. The urging member 82 is a spring material made of a compression coil spring, with its lower end abutting and supported on the upper surface of the retainer 81 and its upper end abutting and supported on the housing 11, and is elastically expandable and contractible in the vertical direction. The urging member 82 urges the lifter body 30 toward the cam 60, exerting an urging force that presses the roller 40 against the cam 60.

[0032] The mounting member 50 is an integral plate-like molded body formed by bending a single metal plate into a predetermined shape. Like the lifter body 30, the mounting member 50 is made of a metal material with excellent wear resistance. The mounting member 50 has a predetermined elasticity. The mounting member 50 is disposed within the lifter body 30. Specifically, as shown in FIGS. 2 and 3, the mounting member 50 is disposed below the partition wall 32 in the lifter body 30.

[0033] 3 and 4, the mounting member 50 has a rotation prevention portion 51, a holding portion 52, and a connecting portion 53. The rotation prevention portion 51 restricts rotation of the lifter body 30 within the hole 12 of the housing 11. As shown in FIG. 1, the rotation prevention portion 51 functions as a rotation prevention device by entering the guide groove 16 of the housing 11. As shown in FIGS. 2 and 3, the rotation prevention portion 51 is inserted into the through-hole 37 from the inside of the lifter body 30 and protrudes radially outward from the lifter body 30.

[0034] As shown in FIG. 3 , the anti-rotation portion 51 has a U-shaped curved surface in a plan view. The anti-rotation portion 51 is closed at the tip end 51A, which is the protruding end, and opens between the pair of base ends 51B. The anti-rotation portion 51 is formed so that its vertical length is slightly smaller than the vertical length of the rectangular through-hole 37. When the anti-rotation portion 51 is in its natural state, the distance between the pair of base ends 51B is slightly larger than the width of the through-hole 37. As a result, when inserted into the through-hole 37, the anti-rotation portion 51 makes contact with the inner surface of the through-hole 37 while applying an elastic force.

[0035] As shown in FIG. 3, the holding portion 52 is held by the shaft 70 on the end face side of the roller 40. The holding portion 52 is arranged along the opposing wall 34 of the peripheral wall 31. As shown in FIG. 4, the holding portion 52 is disk-shaped. The outer diameter of the holding portion 52 is smaller than the outer diameter of the roller 40 and larger than the inner diameter of the roller 40. A pair of holding portions 52 is provided. A holding hole 52A is formed in each of the pair of holding portions 52. Both ends of the shaft 70 are inserted into the holding holes 52A. The inner diameter of the holding hole 52A is slightly larger than the outer diameter of the shaft 70.

[0036] 3, the pair of retaining portions 52 are disposed so as to be sandwiched between the end faces of the rollers 40 and the opposing walls 34. Each retaining portion 52 functions as a thrust washer that supports the end faces of the rollers 40 in the axial direction. Each retaining portion 52 also functions as a thrust washer that supports the end faces of the needle bearings 72 in the axial direction.

[0037] 3 and 4, the connecting portion 53 connects the anti-rotation portion 51 and the retaining portion 52. The connecting portion 53 faces the outer peripheral surface of the roller 40 with a gap therebetween. In this embodiment, the connecting portion 53 is curved along the inner peripheral surface of the arc-shaped wall 36. The connecting portion 53 comes into contact with the inner peripheral surface of the arc-shaped wall 36 when the mounting member 50 is properly attached.

[0038] Next, the operation of the roller lifter 20 will be described along with the assembly procedure. When assembling the roller lifter 20, first, the mounting member 50 is placed inside the lifter body 30. More specifically, the mounting member 50 is inserted into the lifter body 30 from the lower end opening of the lifter body 30. Then, the anti-rotation portion 51 of the mounting member 50 is inserted into the through-hole 37. In other words, the mounting member 50 is moved from the second position to the first position. At this time, the connecting portion 53 is brought into contact with the inner circumferential surface of the arc-shaped wall 36. This places the mounting member 50 in the correct position inside the lifter body 30.

[0039] Next, the roller 40 is placed between the pair of holding portions 52 of the mounting member 50. At this time, a needle bearing 72 is previously placed inside the cylinder of the roller 40 while being held using a temporary holding means. Thereafter, the shaft 70 is inserted into the axial hole 38 of one of the pair of opposing walls 34, and the shaft 70 is inserted into the axial hole 38 of the other of the pair of opposing walls 34 while pushing out the temporary holding means. As a result, the shaft 70 is inserted through one of the pair of opposing walls 34, one of the pair of holding portions 52, the roller 40, the other of the pair of holding portions 52, and the other of the pair of opposing walls 34, in this order. In this state, the mounting member 50 is stably placed inside the lifter body 30, with the anti-rotation portion 51 contacting the inner surface of the through-hole 37 at the outer surface of the base end 51B while applying elastic force, and the shaft 70 being inserted into each of the pair of holding portions 52.

[0040] The roller lifter 20 has the rotation preventing portion 51 that moves back and forth within the guide groove 16 of the housing 11. This restricts the lifter body 30 from rotating around its axis within the hole 12.

[0041] As described above, the roller lifter 20 according to the first embodiment includes a lifter body 30, a shaft 70, rollers 40, and a mounting member 50. The lifter body 30 is cylindrical and can slide back and forth within the hole 12 of the housing 11. Both axial ends of the shaft 70 are supported by a pair of opposing walls 34 that form the peripheral wall 31 of the lifter body 30. The rollers 40 are rotatably supported by the shaft 70 and are disposed within the lifter body 30. The mounting member 50 is disposed within the lifter body 30. The lifter body 30 has a through hole 37 that radially penetrates the peripheral wall 31. The mounting member 50 has a retaining portion 52 and a rotation preventing portion 51. The retaining portion 52 is held by the shaft 70 on the end face side of the rollers 40. The rotation preventing portion 51 extends from the retaining portion 52, passes through the through hole 37, and protrudes outward from the outer circumferential surface of the peripheral wall 31.

[0042] With this configuration, the roller lifter 20 can be easily provided with the anti-rotation portion 51 without requiring strict dimensional accuracy such as press fitting. Furthermore, the mounting member 50 having the anti-rotation portion 51 is stably positioned within the lifter body 30 by the anti-rotation portion 51 inserted into the through-hole 37 and the retaining portion 52 inserted onto the shaft 70. Therefore, the roller lifter 20 can achieve good manufacturability while improving the reliability of the anti-rotation function.

[0043] The mounting member 50 also has a connecting portion 53. The connecting portion 53 connects the holding portion 52 and the anti-rotation portion 51. The mounting member 50 is formed by integrally forming the holding portion 52, the anti-rotation portion 51, and the connecting portion 53 from a single plate material. Therefore, the mounting member 50 of the roller lifter 20 can be easily formed, achieving even better manufacturability.

[0044] The peripheral wall 31 also has a pair of opposing walls 34 and a pair of arc-shaped walls 35, 36. The pair of opposing walls 34 face each other in parallel in the radial direction of the peripheral wall 31. The pair of arc-shaped walls 35, 36 face each other in parallel in the radial direction of the peripheral wall 31. The through-hole 37 is formed in the arc-shaped wall 36, which is one of the pair of arc-shaped walls 35, 36. The holding portions 52 are also arranged in pairs along each of the pair of opposing walls 34. The connecting portion 53 is arranged along the inner circumferential surface of the arc-shaped wall 36. Therefore, the roller lifter 20 can stably arrange the mounting member 50 on the lifter body 30.

[0045] Furthermore, the mounting member 50 is provided so as to be movable between a first position where the anti-rotation portion 51 protrudes outward from the outer circumferential surface of the peripheral wall 31, and a second position where the anti-rotation portion 51 has moved inward of the peripheral wall 31 from the state where it is in the first position. Therefore, the roller lifter 20 allows the mounting member 50 to be easily attached to the lifter body 30.

[0046] Furthermore, anti-rotation portion 51 is in contact with the inner surface of through-hole 37 while applying an elastic force to it, which makes it possible to effectively prevent anti-rotation portion 51 from rattling inside through-hole 37, thereby further improving the reliability of the anti-rotation function.

[0047] Additionally, the connecting portion 53 contacts the inner peripheral surface of the arc-shaped wall 36 that constitutes the peripheral wall 31. This makes it possible to suitably suppress tilt of the mounting member 50 around the central axis of the shaft 70, thereby further improving the reliability of the anti-rotation function.

[0048] Furthermore, roller lifter 20 is configured such that no anti-rotation portion is provided on lifter body 30 by providing anti-rotation portion 51 on mounting member 50. Therefore, lifter body 30 does not have any portion that protrudes radially outward from the outer circumferential surface of peripheral wall 31, so that polishing of the outer periphery of lifter body 30 can be performed without hindrance.

[0049] <Example 2> 5 shows a roller lifter 220 according to Example 2 of this embodiment. Example 2 differs from Example 1 in that a shaft 270 has a circumferential groove 271, that a mounting member 250 is provided so as to be movable between a first position and a second position, and that the mounting member 250 has a restricting portion 254. In the following description, structures that are the same as or equivalent to those in Example 1 are given the same reference numerals, and descriptions that overlap with Example 1 will be omitted.

[0050] 5 and 6, the roller lifter 220 according to the second embodiment includes a lifter body 30, a shaft 270, rollers 40, and a mounting member 250. The shaft 270 has a circumferential groove 271 formed therein. The circumferential groove 271 is formed on the outer circumferential surface of the shaft 270 along the circumferential direction. The width of the circumferential groove 271 is set to be slightly larger than the plate thickness of the mounting member 250. The circumferential grooves 271 are formed in pairs corresponding to the pair of holding portions 252 of the mounting member 250. The pair of circumferential grooves 271 are formed at both axial ends of the shaft 270.

[0051] As shown in FIGS. 5 and 6 , the mounting member 250 has a rotation prevention portion 51, a holding portion 252, and a connecting portion 53. The mounting member 250 is movable between two positions within the lifter body 30. One of these two positions is a first position, and the other is a second position. The direction of movement of the mounting member 250 between these two positions is a direction intersecting the axial direction of the shaft 270. When the mounting member 250 is in the first position, the rotation prevention portion 51 protrudes outward from the outer circumferential surface of the peripheral wall 31. When the mounting member 250 is in the second position, the rotation prevention portion 51 is positioned more inward of the peripheral wall 31 than when the mounting member 250 is in the first position. In this embodiment, when the mounting member 250 is in the second position, the rotation prevention portion 51 is positioned more inward than the outer circumferential surface of the peripheral wall 31.

[0052] Furthermore, when the mounting member 250 is in the first position, it prevents the shaft 270 from coming off. When the mounting member 250 is in the first position, the holding portion 252 is disposed within the circumferential groove 271. In this state, the holding portion 252 restricts the axial displacement of the shaft 270. When the mounting member 250 is in the second position, the holding portion 252 is disposed outside the circumferential groove 271. When the mounting member 250 is in the second position, it allows the axial displacement of the shaft 270.

[0053] The retaining portion 252 has a retaining hole 252A. As shown in Fig. 6, the retaining hole 252A has a shape that is long in one direction, with the longitudinal direction being the direction of movement of the mounting member 250 between the first position and the second position. Specifically, the retaining hole 252A has a so-called keyhole shape in which a large diameter portion 252B and a small diameter portion 252C are aligned and communicated with each other in the direction of movement between the first position and the second position.

[0054] Large diameter portion 252B is disposed at a position closer to anti-rotation portion 51 than small diameter portion 252C. The inner diameter of large diameter portion 252B in retaining hole 252A is set to be larger than the outer diameter of shaft 270. The inner diameter of small diameter portion 252C in retaining hole 252A is set to be smaller than the outer diameter of shaft 270 and slightly larger than the outer diameter of the bottom surface of circumferential groove 271 in shaft 270. Distance L between center C1 of the arc formed by the edge of large diameter portion 252B and center C2 of the arc formed by the edge of small diameter portion 252C corresponds to the movement distance of mounting member 250 when moving between the first position and the second position.

[0055] The mounting member 250 has a restricting portion 254. The restricting portion 254 restricts movement of the mounting member 250 from the first position to the second position. In the present embodiment, the restricting portion 254 is provided on the anti-rotation portion 51, as shown in FIGS. 5 and 6. The restricting portion 254 protrudes from the anti-rotation portion 51 and engages with the opening edge of the through-hole 37 on the outer peripheral surface of the peripheral wall 31. Specifically, the restricting portion 254 is formed by cutting and raising a portion of the base end portion 51B of the anti-rotation portion 51 outward.

[0056] As shown in FIG. 5, in the roller lifter 220, washers W are disposed between each of the retaining portions 252 and both ends of the roller 40. Each washer W restricts the axial displacement of the needle bearing 72, specifically, its intrusion into the large-diameter portion 252B. Similar to the retaining portion 52 in the first embodiment, each washer W functions as a thrust washer that supports the end faces of the roller 40 and the needle bearing 72 in the axial direction. Washers W are not necessary when needle bearings are not used, such as in a so-called single roller in which the roller is directly supported on the shaft or a so-called double roller in which the roller is supported on the shaft via an inner ring with a smaller diameter than the roller. In these cases, the retaining portion 252 can function as a thrust washer, similar to the retaining portion 52 in the first embodiment.

[0057] The operation of the roller lifter 220 will be described together with the assembly procedure. When assembling the roller lifter 220, first, the mounting member 250 is placed inside the lifter body 30. More specifically, the mounting member 250 is inserted into the lifter body 30 from the lower end opening of the lifter body 30. At this time, the mounting member 250 is placed so that the center C1 of the large diameter portion 252B coincides with the center of the shaft hole 38. In other words, the mounting member 250 is placed in the second position. In addition, the roller 40, with the needle bearing 72 held by a temporary holding means, is placed between the pair of holding portions 252 of the mounting member 250.

[0058] Next, the shaft 270 is inserted through the shaft hole 38 of one of the pair of opposing walls 34 and into the other shaft hole 38. As a result, the shaft 270 is inserted through one of the pair of opposing walls 34, one of the pair of retaining portions 252, the washer W, the roller 40, the washer W, the other of the pair of retaining portions 252, and the other of the pair of opposing walls 34, in that order. In this state, as shown in FIG. 8, the mounting member 250 is in a state where the shaft 270 is inserted through the large diameter portion 252B of the retaining hole 252A.

[0059] Then, the mounting member 250 is moved to the first position. As a result, as shown in FIGS. 5 and 7 , the mounting member 250 is in a state in which the anti-rotation portion 51 is inserted into the through-hole 37 and protrudes outward from the outer circumferential surface of the peripheral wall 31, the holding portion 252 is disposed in the circumferential groove 271, and the connecting portion 53 is in contact with the inner circumferential surface of the peripheral wall 31. Furthermore, by moving the mounting member 250 from the second position to the first position, the restricting portion 254 penetrates the through-hole 37 together with the anti-rotation portion 51 and is engaged with the opening edge of the through-hole 37. As a result, movement of the mounting member 250 from the first position to the second position is restricted and the mounting member 250 is held in the first position.

[0060] When the mounting member 250 is in the first position, the anti-rotation portion 51 is in a state in which the outer surface of the base end portion 51B is in contact with the inner surface of the through-hole 37 while applying an elastic force. Furthermore, the retaining portion 252 is in a state in which the shaft 270 is inserted through the small-diameter portion 252C of the retaining hole 252A within the circumferential groove 271. Furthermore, the connecting portion 53 is in a state in which it is in contact with the inner circumferential surface of the arc-shaped wall 36. When the mounting member 250 is in the first position, the states of the anti-rotation portion 51, the retaining portion 252, and the connecting portion 53 are maintained by the restricting portion 254. Therefore, the mounting member 250 in the first position is stably disposed within the lifter body 30.

[0061] Furthermore, in the mounting member 250 whose movement from the first position to the second position is restricted by the restricting portion 254, the retaining portion 252 is maintained in a state where it is disposed within the circumferential groove 271. As a result, the axial displacement of the shaft 270 is restricted without requiring any retaining processing such as crimping. In this manner, in the roller lifter 220, the axial displacement of the shaft 270 is restricted by the retaining portion 252 of the mounting member 250, so the roller lifter 220 does not require any process such as crimping to prevent or fix the shaft 270. Furthermore, because the shaft 270 is rotatable with respect to the shaft hole 38, uneven wear is suppressed, unlike when the shaft 270 is fixed within the shaft hole 38.

[0062] The roller lifter 220 configured as described above also achieves the same functions and effects as those of the first embodiment. Furthermore, in the roller lifter 220, the shaft 270 has a circumferential groove 271 formed on its outer surface along the circumferential direction of the shaft 270. The retaining portion 252 has a retaining hole 252A formed therein, through which the shaft 270 passes. When the mounting member 250 is in the first position, the peripheral portion of the retaining hole 252A in the retaining portion 252 is disposed within the circumferential groove 271. This allows the mounting member 250 to also function as a retainer for the shaft 270. This eliminates the need to provide a separate shaft retaining function, such as crimping, thereby achieving even better manufacturability.

[0063] Furthermore, in the roller lifter 220, the mounting member 250 has a restricting portion 254. The restricting portion 254 restricts movement of the mounting member 250 from the first position to the second position. This allows the mounting member 250 to be suitably held in the first position, effectively restricting the anti-rotation portion 51 from falling off from the through-hole 37 and further improving the reliability of the anti-rotation portion 51. Furthermore, since the retaining portion 252 can be suitably restricted from falling off from the circumferential groove 271, the shaft 270 can be suitably held in a locked state.

[0064] Furthermore, in the roller lifter 220, the restricting portion 254 is provided to protrude from the outer surface of the base end portion 51B of the anti-rotation portion 51, and is configured to engage with the opening edge of the through-hole 37 in the outer peripheral surface of the peripheral wall 31. This allows the restricting portion to be provided with a simple configuration, thereby achieving even better manufacturability.

[0065] <Other Examples> The present disclosure is not limited to the embodiments described above and illustrated in the drawings, and the following aspects, for example, are also included within the technical scope of the present disclosure. (1) In the above-described first and second embodiments, the mounting member is made of the same material as the lifter body, but the material, shape, etc. of the mounting member according to the present disclosure are not particularly limited. (2) In the above-described first and second embodiments, the anti-rotation portion contacts the inner surface of the through hole while applying an elastic force to the anti-rotation portion, but this is not essential. For example, the anti-rotation portion may be disposed with a gap between it and the inner surface of the through hole. (3) In the above-described first and second embodiments, the connecting portion of the mounting member is in contact with the inner circumferential surface of the peripheral wall, but this is not essential. For example, the connecting portion may be disposed with a gap between it and the inner circumferential surface of the peripheral wall. (4) In the above-mentioned Examples 1 and 2, the through hole is formed in the axial center of the peripheral wall, but this is not essential. The through hole may be formed closer to the axial end of the peripheral wall, but it is preferable to form it as close to the axial center of the peripheral wall as possible. This is because the anti-rotation portion protruding from the through hole can be positioned in the axial center of the peripheral wall. From the viewpoint of the stability of the roller lifter within the hole in the housing, it is preferable that the anti-rotation portion be provided closer to the axial center of the lifter body. (5) In the above-described first and second embodiments, the anti-rotation portion has a U-shaped curved surface in plan view, but this is not essential. The anti-rotation portion may have, for example, a rectangular curved shape in plan view (a U-shape). The anti-rotation portion may also be solid, with no internal space. (6) In the second embodiment, the circumferential groove is formed around the entire circumference of the shaft, but this is not essential. For example, instead of the circumferential groove being formed around the entire circumference, the groove may be formed only around a portion of the circumference of the shaft. (7) In the second embodiment, the restricting portion is formed on the anti-rotation portion, but this is not essential. When the mounting member has the restricting portion, the restricting portion may be formed on a portion other than the anti-rotation portion, such as a holding portion or a connecting portion. When the restricting portion is formed on the anti-rotation portion, for example, a through-hole 337 formed in a stepped shape in the radial direction as shown in FIG. 9 may be formed on the peripheral wall 331. In this case, the restricting portion 254 can be positioned inside the outer circumferential surface of the peripheral wall 331, and the restricting portion 254 can be prevented from contacting the inner surface of the guide groove 16. (8) When the restricting portion is formed in the retaining portion, its shape may be, for example, a C-ring shape, an E-ring shape, or a shape in which a portion of the retaining portion is formed with a notch so that a portion of the retaining hole is open to the outside. In this case, the retaining portion may be configured to be elastically expandable like a C-ring or E-ring. The retaining portion can restrict movement of the mounting member from the first position to the second position by inserting the shaft into the retaining hole through the notch-shaped portion of the retaining portion and then elastically returning to its original position to be held by the shaft. Furthermore, when the retaining hole is an oval hole shape, the configuration of the small diameter portion may be configured as a C-ring shape or an E-ring shape. (9) In the second embodiment, the retaining hole is formed in a so-called potbellied shape. However, the retaining hole may be formed in any size and shape that allows the mounting member to move between the first position and the second position. For example, mounting member 450 shown in FIG. 10 has a retaining portion 452 in which an elongated retaining hole 452A is formed. In this case, too, by moving mounting member 450 from the second position to the first position, retaining portion 452 can be positioned within circumferential groove 271, thereby restricting axial displacement of shaft 270. (10) The holes in the housing according to the present disclosure may be formed directly in the housing, or may be holes formed in a component, such as a lifter guide, that is provided separately from the housing and assembled to the housing. (11) The roller lifter according to the present disclosure may be used as a roller tappet in a valve train of an internal combustion engine. [Explanation of symbols]

[0066] 11. Housing 12...Housing hole 20,220... Roller lifter 30...Lifter body 31, 331... Peripheral wall (33... Cylindrical wall, 34... Opposing wall, 35, 36... Arc-shaped wall) 37,337...Through holes 40...Laura 50, 250, 450...Mounting parts 51...Stop 52,252,452…Holding part 52A, 252A, 452A…Retaining hole 53...Connection part 70,270...shaft 254…Regulatory Department 271...Circumferential groove

Claims

1. a cylindrical lifter body that can reciprocate and slide within a hole in the housing; a shaft whose axial ends are supported by the peripheral wall of the lifter body; a roller rotatably supported on the shaft; a mounting member disposed within the lifter body; Equipped with the lifter body has a through-hole penetrating the peripheral wall at a center of the peripheral wall in the axial direction, The mounting member is a holding portion that is held by the shaft on an end face side of the roller; a rotation preventing portion extending from the holding portion, passing through the through hole, and protruding outward from an outer peripheral surface of the peripheral wall; The roller lifter has:

2. 2. The roller lifter according to claim 1, wherein the mounting member has a connecting portion that connects the holding portion and the anti-rotation portion, and is integrally formed from a single plate material.

3. The peripheral wall has a pair of opposing walls that are parallel to each other in a radial direction of the peripheral wall, and a pair of arc-shaped walls that are curved and disposed between the pair of opposing walls in the circumferential direction of the peripheral wall, the through hole is formed in one of the pair of arc-shaped walls, The holding portions are arranged in pairs along the opposing walls, The roller lifter according to claim 2 , wherein the connecting portion is disposed along an inner circumferential surface of one of the pair of arc-shaped walls.

4. A cylindrical lifter body that can slide back and forth within a hole in a housing; a shaft whose axial ends are supported by the peripheral wall of the lifter body; a roller rotatably supported on the shaft; a mounting member disposed within the lifter body; Equipped with The lifter body has a through hole penetrating the peripheral wall, The mounting member is a holding portion that is held by the shaft on an end face side of the roller; a rotation preventing portion extending from the holding portion, passing through the through hole, and protruding outward from an outer peripheral surface of the peripheral wall; and The mounting member is a roller lifter that is movable between a first position in which the anti-rotation portion protrudes outward from the outer peripheral surface of the peripheral wall and a second position in which the anti-rotation portion has moved inward of the peripheral wall from the state in which it is in the first position.

5. The shaft has a circumferential groove formed on an outer surface thereof along a circumferential direction of the shaft, The holding portion has a holding hole through which the shaft passes, 5. The roller lifter according to claim 4, wherein when the mounting member is in the first position, a peripheral edge of the holding hole in the holding portion is disposed within the circumferential groove.

6. 6. The roller lifter according to claim 4, wherein the mounting member has a restricting portion that restricts movement from the first position to the second position.

7. 7. The roller lifter according to claim 6, wherein the restricting portion is provided so as to protrude from the anti-rotation portion and is engaged with an opening edge of the through hole in the outer peripheral surface of the peripheral wall.

8. The roller lifter according to any one of claims 1 to 7, wherein the anti-rotation portion is in contact with the inner surface of the through hole while applying an elastic force to the anti-rotation portion.

9. The lifter body has a partition wall formed in a flat plate shape along the radial direction within the peripheral wall, the shaft is supported by the peripheral wall on one side of the peripheral wall in the axial direction relative to the partition wall, The roller lifter according to claim 1 , wherein the through-hole is formed in the peripheral wall on the one side of the partition wall.

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