JP2022138241A - rocker arm - Google Patents

Abstract

To improve workability.SOLUTION: A rocker arm 6 comprises: a long shaft part 13; a roller 7 attached to the shaft part 13 in a rotatable state; a main body part 9 which includes a pair of sidewalls 12 disposed to hold the roller 7 therebetween and where shaft passing parts 12A through which the shaft part 13 is passed are respectively opened and formed on the pair of sidewalls 12; and a roller bearing part 16 interposed between the shaft part 13 and the roller 7 and consisting of a plurality of rollers 16A arranged side by side in a circumferential direction of the shaft part 13. The shaft part 13 includes a pair of supported portions 13B supported rotatably by peripheral surfaces of the shaft passing portions 12A on the pair of sidewalls 12. The main body part 9 includes a pair of roller holding portions 17 in which an opening area of the shaft passing portion 12A is larger than a cross-sectional area of a cross section orthogonal with an axial direction of the shaft part 13 in the supported portion 13B and the plurality of rollers 16A is held while being sandwiched from an outside in the axial direction of the shaft part 13.SELECTED DRAWING: Figure 4

Description

The technology disclosed in this specification relates to a rocker arm.

A rocker arm serves to convert the rotary motion of a cam that rotates in conjunction with a crankshaft to a reciprocating motion of a valve shaft of an intake valve or an exhaust valve of the internal combustion engine. As an example of such a rocker arm, one described in Patent Document 1 below is known. In the rocker arm disclosed in Patent Document 1, support recesses are formed in both opposing side walls so that both ends of the support shaft can be mounted with a radial engagement margin, and roller bearings with cages attached to the support shaft are formed. It is a structure in which both end portions of the support shaft used as the assembly are mounted in both support recesses.

Japanese Unexamined Patent Application Publication No. 2005-201065

The rocker arm disclosed in Patent Document 1 has a roller bearing with a retainer. The retainer that constitutes the roller bearing has a cylindrical shape, and has a plurality of grooves formed at intervals in the circumferential direction on the circumferential surface thereof for individually mounting the rollers. For this reason, when assembling, it is necessary to individually attach a plurality of rollers to the respective grooves of the retainer, which poses a problem of poor assembling workability.

The technique described in this specification has been perfected based on the circumstances as described above, and aims to improve workability.

(1) A rocker arm related to the technology described in this specification has a longitudinal shaft, a roller rotatably attached to the shaft, and a pair of side walls arranged to sandwich the roller. a main body having openings formed in the pair of side walls for allowing the shaft to pass therethrough; a roller bearing portion composed of rollers, the shaft portion having a pair of supported portions that are rotatably supported by the peripheral surface of the shaft through portion of the pair of side walls; In the body portion, the opening area of the shaft through portion is larger than the cross-sectional area of the section perpendicular to the axial direction of the shaft portion in the supported portion, and the plurality of rollers are sandwiched from the outside in the axial direction. A pair of roller holding portions are provided to hold the rollers.

With this configuration, the roller sandwiched between the pair of side walls of the main body is rotatable by being supported by the shaft. Smooth rotation of the roller is ensured by interposing a roller bearing portion composed of a plurality of rollers arranged along the circumferential direction of the shaft portion between the roller and the shaft portion. The shaft portion is rotatable by being passed through the shaft through portions formed in the pair of side walls of the body portion, and each supported portion being supported by the peripheral surface of each shaft through portion. Since the shaft is rotatable with respect to the main body, the load acting on the shaft from the roller via the roller bearing is dispersed in the circumferential direction of the shaft, thereby preventing uneven wear on the shaft. Become.

In the main body, the opening area of the shaft through portion is made larger than the cross-sectional area of the section perpendicular to the axial direction of the shaft in the supported portion, so that the shaft can be easily assembled to the main body. there is However, in doing so, there is a possibility that some of the rollers forming the roller bearing portion will not be held by the pair of side walls. On the other hand, when a cage is used to hold a plurality of rollers as in the prior art, a plurality of grooves are formed on the circumferential surface of the cylindrical cage at intervals in the circumferential direction. On the other hand, there is a problem that the workability is not good because it requires work to individually attach a plurality of rollers.

Therefore, if a configuration is adopted in which a plurality of rollers arranged along the circumferential direction of the shaft are sandwiched from the outer side in the axial direction of the shaft by a pair of roller holding portions, the opening area of the shaft-passing portion is reduced to the supported portion. A plurality of rollers can be appropriately held even if the cross-sectional area is larger than the cross-sectional area of the shaft perpendicular to the axial direction of the shaft. Moreover, during assembly, a plurality of rollers arranged in contact with each other along the circumferential direction of the shaft may be sandwiched from the outside by a pair of roller holding portions in the axial direction. As compared with the case where a plurality of rollers are individually mounted in a plurality of grooves formed with openings, the assembling workability is improved.

(2) In addition to the above (1), the rocker arm has a shaft main body in which the roller bearing portion is interposed between the shaft portion and the roller, and the main body portion is formed in the side wall in the shape of a hole surrounding the shaft portion, and the maximum opening diameter of the shaft passing portion is larger than the maximum outer diameter of the shaft portion, the difference between the maximum outer diameter of the shaft portion, the outer diameter of the shaft main body and the A half of the difference from the outer diameter of the supported portion and the sum of the outer diameter of the roller is smaller than the outer diameter of the roller. It may be constituted by a rim. First, since the shaft-passing portion is formed in the side wall in the shape of a hole surrounding the shaft portion, compared to the case where the shaft-passing portion is formed in the side wall in the shape of a groove opening in one direction along the wall surface, the main body portion The mechanical strength of can be kept high. In addition, by making the maximum opening diameter of the shaft-passing portion larger than the maximum outer diameter of the shaft portion, the ease of assembly of the shaft portion to the shaft-passing portion is ensured. Furthermore, the sum of the difference between the maximum opening diameter of the shaft through portion and the maximum outer diameter of the shaft portion and half the difference between the outer diameter of the shaft body and the supported portion is larger than the outer diameter of the roller. Since it is configured to be small, when the shaft is passed through the shaft through portion and the supported portion is supported, the plurality of rollers are moved in the axial direction of the shaft portion by the hole edges of the shaft through portion in the pair of side walls. pinched from the outside. That is, since the hole edges of the shaft-passing portions in the pair of side walls constitute a pair of roller holding portions that hold a plurality of rollers, if the pair of roller holding portions are prepared as separate parts from the main body, Compared to , the number of parts can be reduced.

(3) In the rocker arm, in addition to (2) above, the shaft portion has a portion to be supported that has a smaller diameter than the shaft main body, and the main body portion has the shaft through portion It may be configured to include a shaft body passage portion through which the main body passes, and an extension portion formed by expanding a part of the peripheral surface of the shaft body passage portion and supporting the supported portion by the peripheral surface thereof. . With this configuration, the shaft body of the shaft portion is passed through the shaft body threading portion of the shaft threading portion, so that the shaft portion can be assembled to the body portion. The supported portion of the shaft portion has a diameter smaller than that of the shaft body, and is supported by the peripheral surface of the expanded portion formed by partially expanding the peripheral surface of the shaft body through portion of the shaft through portion. Therefore, compared to the case where the extended portion is not formed and the portion to be supported is supported by the peripheral surface of the shaft body through portion, the peripheral surface of the extended portion can stably support the portion to be supported.

(4) In the rocker arm, in addition to (3) above, the main body portion may be configured such that the peripheral surface of the extended portion is arcuate with the same radius of curvature as the outer peripheral surface of the supported portion. good. With this configuration, the outer peripheral surface of the supported portion comes into surface contact with the peripheral surface of the expanded portion, so that the supported portion is more stably supported by the peripheral surface of the expanded portion.

(5) Further, in addition to (3) or (4) above, the rocker arm may be configured such that the peripheral surface of the shaft body through portion of the body portion is along the outer peripheral surface of the shaft body. . In this way, the opening range of the shaft body passage portion can be minimized to allow the shaft body to pass therethrough. As a result, deterioration in the strength of the side wall due to the opening of the shaft body passage portion in the side wall is suppressed. The maximum opening diameter of the shaft through portion is the maximum opening diameter across the shaft body through portion and the expanded portion, and the maximum outer diameter of the shaft portion is the outer diameter of the shaft main body. The difference between the maximum opening diameter and the maximum outer diameter of the shaft portion is approximately the size of the expanded portion of the shaft through portion.

(6) In addition to the above (5), the rocker arm has the shaft portion arranged to face the surface of the pair of side walls opposite to the roller, and is the same as the shaft main body. It may have a pair of retainers having an outer diameter. With this configuration, the pair of retainer portions are arranged to face the surfaces of the pair of side walls arranged to sandwich the roller, which are opposite to the roller, so that they can be secured to the body portion. Therefore, it is possible to prevent the axially assembled shaft portion from being displaced in its axial direction and falling off. Moreover, since the retainer has the same outer diameter as that of the shaft body, it is passed through the shaft body through portion included in the shaft through portion during assembly. As a result, compared to the case where the retaining portion has an outer diameter larger than that of the shaft main body, the opening range of the shaft receiving portion can be kept small, which is suitable for keeping the mechanical strength of the main body high. .

(7) In addition to (1) above, the rocker arm may be arranged such that the pair of roller holding portions are interposed between the roller and the pair of side walls. As described above, since the roller holding portion is a separate part from the main body, the plurality of rollers can be firmly held by the pair of roller holding portions regardless of the opening range of the shaft-passing portion of the side wall. be able to.

(8) In the rocker arm, in addition to the above (7), the main body portion may be formed in the shape of a groove in which the shaft-passing portion opens in one direction along the wall surface of the side wall. With this configuration, when the shaft is assembled to the main body, the shaft may be passed through the groove-shaped shaft-passing portion of each side wall along the opening direction thereof. Since it is possible to assemble the roller bearing portion, the roller, and the pair of roller holding portions to the shaft portion prior to assembling to the main body portion, the assembling workability is improved.

(9) Further, in addition to (7) or (8) above, the rocker arm has a mounting portion on which the roller holding portion is mounted on the shaft portion, and the mounting portion extends from the axial direction. The roller holding portion has a mounting portion passage portion through which the mounting portion is passed. The roller holding portion may be circular, and the roller holding portion may come into contact with the roller. With this configuration, when the roller holding portion is attached to the mounting portion of the shaft portion, the mounting portion is passed through the mounting portion passing portion of the roller holding portion, and the roller holding portion is in contact with the roller. Therefore, when the roller is rotated, the peripheral surface of the mounting portion passing portion, which is formed in a non-circular shape when viewed from the axial direction of the shaft portion, of the roller holding portion in contact with the roller is formed into a non-circular shape when viewed from the axial direction of the shaft portion. Since a rotational force is transmitted to the shaped mounting portion, the rotational force promotes rotation of the shaft. In other words, since the rotational force of the roller can be used to rotate the shaft by transmitting it to the shaft via the roller holding portion, the load acting on the shaft from the roller via the roller bearing portion can be applied to the shaft. , so that uneven wear is less likely to occur in the shaft portion. Further, since the roller holding portion is configured to contact the roller, it is highly certain that the function of holding the plurality of rollers interposed between the roller and the shaft portion is exhibited.

(10) In the rocker arm, in addition to the above (1), the main body portion is formed in a groove shape in which the shaft through portion opens in one direction along the wall surface of the side wall, and the shaft portion is and a shaft body in which the roller bearing portions are interposed between the rollers, and the pair of the supported portions are larger in diameter than the shaft body and have a difference from the outer diameter of the shaft body. may be made smaller than the outer diameter of the roller to constitute the pair of roller holding portions. With this configuration, the outer diameter of the pair of supported portions is made larger than the outer diameter of the shaft body, so that the plurality of rollers forming the roller bearing portion interposed between the shaft body and the roller are are arranged to face the side surfaces of the supported portions of the . That is, the plurality of rollers are sandwiched from the outside in the axial direction of the shaft portion by the pair of supported portions, and the pair of supported portions constitute a pair of roller holding portions that hold the plurality of rollers. Therefore, compared with the case where a pair of roller holding portions are prepared as separate parts from the shaft portion, it is possible to reduce the number of parts. Moreover, since half of the difference between the outer diameter of the supported portion and the outer diameter of the shaft body is smaller than the diameter of the rollers, workability is improved when assembling a plurality of rollers between the shaft body and the rollers of the shaft portion. become good. Further, when the shaft portion, to which the rollers and the roller bearing portions are previously assembled, is assembled to the main body portion, the shaft portion may be passed through the groove-shaped shaft-passing portion along the opening direction thereof.

According to the technique described in this specification, workability can be improved.

1 is a cross-sectional view of a valve train for an internal combustion engine according to Embodiment 1; Sectional view of a rocker arm provided in the valve train Side view of rocker arm A cross-sectional view of the rocker arm shown in FIG. 3 Front view of the shaft provided on the rocker arm Side view of the main body provided on the rocker arm A cross-sectional view taken along the line AA of FIG. 3 showing a state before the shaft is passed through the shaft body through portion of the shaft through portion of the main body in which the roller and the roller bearing portion are accommodated; A cross-sectional view taken along the line AA in FIG. 3 showing the state after the shaft has been passed through the shaft main body passing portion of the shaft passing portion The side view which shows the state after the shaft part is passed through the shaft main body passing part of the shaft passing part. Side view of rocker arm according to Embodiment 2 A cross-sectional view of the rocker arm shown in FIG. 3 Side view showing a state in which rollers, shafts, roller bearings, and roller holders are assembled. Front view of shaft A side view showing a state before the shaft portion assembled with the roller, the roller bearing portion, and the roller holding portion is passed through the shaft through portion of the main body portion. Side view of rocker arm according to Embodiment 3 A cross-sectional view of the rocker arm shown in FIG. 3 A side view showing a state before the shaft portion assembled with the roller, the roller bearing portion, and the roller holding portion is passed through the shaft through portion of the main body portion.

<Embodiment 1>
Embodiment 1 will be described with reference to FIGS. 1 to 9. FIG. FIG. 1 is a sectional view of a valve train of an internal combustion engine. FIG. 1 shows the upper part of the cylinder head 1, in which a valve gear consisting of a pivot 2, a camshaft 3, an engine valve 4, a valve spring 5 and a rocker arm 6 is provided.

The rocker arm 6 is in the form of a roller rocker arm having a roller 7 which contacts the outer circumference of the cam 3A of the camshaft 3, as shown in FIG. One end of the rocker arm 6 is formed with a swinging fulcrum 8 that abuts on the upper end of the pivot 2, while the other end of the rocker arm 6 (opposite to the swinging fulcrum 8 side) is provided with an engine. A stem abutting portion 10 that engages with the upper end of the stem (valve stem) 4A of the valve 4 is formed. The swing axis of this rocker arm 6 is parallel to the direction normal to the plane of FIG. Thus, in the above-described valve train, the rocker arm 6 swings around the swing fulcrum 8 as the camshaft 3 rotates, and when the upper end of the stem 4A is pushed against the valve spring 5, the engine The valve 4 opens and closes each port for intake and exhaust of the engine at a predetermined timing. The pivot 2 is a member that supports the swing fulcrum 8 of the rocker arm 6, and is attached to the cam housing 14, for example.

As shown in FIG. 2, the rocker arm 6 includes a body portion (rocker arm body) 9, a roller 7 incorporated in the body portion 9, a shaft portion 13 that rotatably supports the roller 7, and the roller 7. and a roller bearing portion 16 interposed between the shaft portion 13 and the shaft portion 13 . The body portion 9 is integrally formed by bending a metal plate with a press, and the central portion thereof serves as a roller accommodating portion 11 for accommodating the roller 7 . The roller accommodating portion 11 has openings on both upper and lower sides shown in FIG. 2, and the rollers 7 are accommodated through the openings. The roller accommodating portion 11 has a pair of side walls 12 arranged so as to sandwich the roller 7 from both sides in the thickness direction (the axial direction of the shaft portion 13). A shaft portion 13 for supporting the roller 7 is bridged between the pair of side walls 12 . The pair of side walls 12 are formed with openings 12A through which the shaft portions 13 are passed. Each shaft through portion 12A is formed in the shape of a hole surrounding the shaft portion 13 in each side wall 12, and has an endless annular peripheral surface. In other words, each shaft through portion 12A has a through-hole shape that penetrates the wall surface of each side wall 12 along its normal direction (wall thickness direction). In this way, the mechanical strength of the main body 9 can be kept high compared to the case where the shaft through portion is formed in the side wall 12 in the shape of a groove opening along the wall surface in one direction.

As shown in FIGS. 1 and 2, the roller 7 has a substantially cylindrical shape as a whole (doughnut shape when viewed from the axial direction of the shaft portion 13), and the shaft portion (roller support shaft) 13 is at the center position. A hole portion 7A is formed to pass through along the width direction. The shaft portion 13 has a substantially cylindrical shape as a whole. As shown in FIGS. 3 and 4, the shaft portion 13 is passed through a shaft main body 13A through which the rollers 7 pass, and the shaft through portions 12A of the pair of side walls 12, and is supported by the peripheral surfaces of the shaft through portions 12A. and a pair of supported portions 13B.

As shown in FIG. 2, the roller bearing portion 16 is interposed between the facing peripheral surfaces of the roller 7 and the shaft main body 13A of the shaft portion 13. As shown in FIG. The roller bearing portion 16 is composed of a plurality of rollers (rolling elements) 16A arranged along the circumferential direction of the facing peripheral surfaces of the roller 7 and the shaft body 13A. The rollers 16A have a cylindrical shape with an axis parallel to the axial direction of the shaft portion 13, and are arranged between the opposed peripheral surfaces so as to form an annular shape centered on the shaft portion 13 and contact each other. The rotation of the roller 7 is facilitated by interposing the roller bearing portion 16 having such a configuration between the facing peripheral surfaces of the roller 7 and the shaft body 13A.

Further, as shown in FIG. 2, the swing fulcrum 8 arranged on one end side of the body portion 9 is bulged by drawing to form a dome shape so as to fit over the upper end portion of the pivot 2 in an aligned state. It consists of a receiving projection 15 . On the other hand, the stem contact portion 10 arranged on the other end side of the main body portion 9 is arranged in such a manner as to be sandwiched between the end portions of the pair of side walls 12 on the side opposite to the swing fulcrum 8 side, and linked to.

As shown in FIG. 4, the shaft portion 13 according to the present embodiment is supported such that the pair of supported portions 13B are passed through the shaft through portions 12A formed in the pair of side walls 12 of the body portion 9, respectively. , and is rotatable with respect to the body portion 9 . Since the shaft portion 13 is rotatable with respect to the main body portion 9 in this manner, the load acting on the shaft portion 13 from the roller 7 via the roller bearing portion 16 is dispersed in the circumferential direction of the shaft portion 13 . As a result, uneven wear is less likely to occur in the shaft portion 13, resulting in excellent durability. In addition, if the shaft is crimped and fixed to the main body 9, the deformed portion of the shaft may interfere with the rollers 16A. By adopting a configuration in which the shaft portion 13 is rotatably supported with respect to the main body portion 9 as in the present embodiment, it is not necessary to crimp the shaft portion 13, which is suitable for miniaturization. there is

By the way, in order to secure the ease of assembly of the shaft portion 13 to the main body portion 9, the opening area of the shaft through portion 12A formed in the side wall 12 of the main body portion 9 should be aligned with the axial direction of the shaft portion 13 in the supported portion 13B. It is conceivable to make it larger than the cross-sectional area of the orthogonal cut surface. For example, in the present embodiment, as shown in FIGS. 3 and 4, the main body portion 9 is such that the opening area of the shaft through portion 12A formed in the side wall 12 is perpendicular to the axial direction of the shaft portion 13 at the supported portion 13B. It is made larger than the cross-sectional area of the cut surface. More specifically, in the present embodiment, the shaft through portion 12A has a through-hole shape that penetrates the wall surface of the side wall 12 along the normal direction. width) D1 is made larger than the maximum outer diameter D2 of the shaft portion 13 . However, there is a possibility that some of the rollers 16</b>A forming the roller bearing portion 16 may not be held by the pair of side walls 12 . On the other hand, when a retainer is used to hold a plurality of rollers 16A as in the conventional art, a plurality of grooves are formed on the circumferential surface of the cylindrical retainer at intervals in the circumferential direction. Since it is necessary to individually attach a plurality of rollers 16A to each other, there is a problem that workability is not good.

Therefore, as shown in FIG. 4, the rocker arm 6 according to the present embodiment includes a pair of roller holding portions 17 that sandwich and hold the plurality of rollers 16A from the outside in the axial direction of the shaft portion 13 (horizontal direction shown in FIG. 4). It has In this embodiment, the roller holding portion 17 is formed by part of the side wall 12 of the body portion 9, as will be described in detail below.

First, as shown in FIGS. 4 and 6, the shaft through portion 12A formed in the side wall 12 of the main body portion 9 includes a shaft main through portion 12A1 through which the shaft main body 13A of the shaft portion 13 is passed, and a shaft main through portion 12A1. and an extended portion 12A2 which is formed by extending a part of the peripheral surface of and supports the supported portion 13B. The shaft body through portion 12A1 has an arcuate peripheral surface similar to the outer peripheral surface of the shaft body 13A, and its outer diameter is slightly larger than the outer diameter of the shaft body 13A. On the other hand, as shown in FIGS. 4 and 5, the shaft portion 13 has a pair of supported portions 13B smaller in diameter than the shaft body 13A. Therefore, the opening area of the shaft through portion 12A is made larger than the cross-sectional area of the section perpendicular to the axial direction of the shaft portion 13 in the supported portion 13B, and the maximum opening diameter D1 is the maximum diameter of the shaft portion 13. The extension portion 12A2 is larger than the outer diameter D3 of the shaft main body 13A, which is the outer diameter D2. As described above, the ease of assembly of the shaft portion 13 to the main body portion 9 is enhanced.

On the other hand, as shown in FIG. 4, the main body portion 9 has a difference (D1-D2) between the maximum opening diameter D1 of the shaft through portion 12A and the maximum outer diameter D2 of the shaft portion 13, and the outer diameter of the shaft main body 13A. The sum of half the difference between D3 and the outer diameter D4 of the supported portion 13B ((D3-D4)/2) is smaller than the outer diameter D5 of the roller 16A. The sum of the above-described difference (D1-D2) and half of the difference ((D3-D4)/2) is obtained by passing the shaft portion 13 through the shaft-passing portion 12A and extending the supported portion 13B around the extended portion 12A2. This is the maximum frontage of the portion of the axial portion 12A that is exposed to the outside without being blocked by the shaft portion 13 in the state supported by the surface. Since this maximum frontage is smaller than the outer diameter D5 of the roller 16A, when the shaft portion 13 is passed through the shaft through portion 12A and the supported portion 13B is supported by the peripheral surface of the extended portion 12A2, a plurality of All of the rollers 16A are sandwiched from the outside in the axial direction of the shaft portion 13 by the hole edges of the shaft through portions 12A in the pair of side walls 12 . That is, the hole edges of the shaft through portions 12A in the pair of side walls 12 form a pair of roller holding portions 17 that collectively hold a plurality of rollers 16A arranged along the circumferential direction of the shaft portion 13. As shown in FIG. According to such a configuration, even if the opening area of the shaft through portion 12A is larger than the cross-sectional area of the section perpendicular to the axial direction of the shaft portion 13 in the supported portion 13B, the plurality of rollers 16A can be properly connected. can be held. Moreover, during assembly, a plurality of rollers 16A arranged along the circumferential direction of the shaft portion 13 in contact with each other are sandwiched from the outside by a pair of roller holding portions 17 in the axial direction, and are held as in the conventional art. As compared with the case where a plurality of rollers 16A are individually mounted in a plurality of grooves formed in the container, workability for assembly is improved. Moreover, since the pair of roller holding portions 17 are provided integrally with the main body portion 9, the number of parts can be reduced compared to the case where the pair of roller holding portions are prepared as separate parts from the main body portion 9. can be planned.

Furthermore, as shown in FIGS. 3 and 4, the supported portion 13B of the shaft portion 13 has a diameter smaller than that of the shaft main body 13A, and the peripheral surface of the shaft main body passing portion 12A1 of the shaft passing portion 12A is Since it is supported by the peripheral surface of the expanded portion 12A2 formed by expanding a part, the expanded portion 13B is supported by the peripheral surface of the shaft body through portion 12A1 without forming the expanded portion. The supported portion 13B can be stably supported by the peripheral surface of the portion 12A2. In addition, as shown in FIGS. 3 and 6, the body portion 9 is configured such that the peripheral surface of the extension portion 12A2 has an arc shape with substantially the same radius of curvature as the peripheral surface of the supported portion 13B. In this way, the outer peripheral surface of the supported portion 13B comes into surface contact with the peripheral surface of the expanded portion 12A2, so that the supported portion 13B is more stably supported by the peripheral surface of the expanded portion 12A2. . This makes it difficult for the shaft portion 13 rotated with respect to the main body portion 9 to be displaced so as to swing left and right as shown in FIG. The radius of curvature of the peripheral surface of the extended portion 12A2 is smaller than the radius of curvature of the peripheral surface of the shaft body through portion 12A1.

Further, as shown in FIGS. 3 and 6, the main body portion 9 is configured so that the peripheral surface of the shaft main body through portion 12A1 is arcuate along the outer peripheral surface of the shaft main body 13A. can be minimized to allow the shaft body 13A to pass therethrough. As a result, a decrease in the strength of the side wall 12 due to the opening of the shaft body through portion 12A1 in the side wall 12 is suppressed. The peripheral surface of the shaft body through portion 12A1 has substantially the same radius of curvature as the outer peripheral surface of the shaft body 13A. The center C1 of the peripheral surface of the shaft body through portion 12A1 is positioned above the center C2 of the peripheral surface of the extended portion 12A2 in the vertical direction. In FIG. 6, the extended line of the peripheral surface of the shaft body through portion 12A1 and the extended line of the peripheral surface of the extended portion 12A2 are each indicated by two-dot chain lines. When the supported portion 13B of the shaft portion 13 is supported by the peripheral surface of the extended portion 12A2, the axial center of the shaft portion 13 does not coincide with the center C1 of the peripheral surface of the shaft body through portion 12A1. is concentrically aligned with the center C2 of the peripheral surface of the . On the other hand, when the shaft body 13A of the shaft portion 13 is passed through the shaft body passage portion 12A1 during assembly, the shaft center of the shaft portion 13 coincides with the center C1 of the peripheral surface of the shaft body passage portion 12A1 (see FIGS. 8 and 8). See Figure 9). The distance between the center C1 of the peripheral surface of the shaft body through portion 12A1 and the center C2 of the peripheral surface of the extended portion 12A2 is the distance between the extension line of the peripheral surface of the shaft body through portion 12A1 and the peripheral surface of the extended portion 12A2. approximately equal to the maximum distance between Note that the maximum opening diameter D1 of the shaft through portion 12A is the width of the opening that straddles the shaft body through portion 12A1 and the extended portion 12A2, and the maximum outer diameter D2 of the shaft portion 13 is the outer diameter of the shaft main body 13A. Therefore, the difference between the maximum opening diameter D1 of the shaft-passing portion 12A and the maximum outer diameter D2 of the shaft portion 13 is approximately the size of the expanded portion 12A2 of the shaft-passing portion 12A.

4 and 5, the shaft portion 13 has a pair of retaining portions 13C arranged to face the surfaces of the pair of side walls 12 opposite to the roller 7, respectively. The retainer portion 13C is positioned on the outer side of the supported portion 13B in the axial direction, that is, on the side opposite to the shaft main body 13A side, and constitutes the outermost end portion of the shaft portion 13. As shown in FIG. According to such a configuration, the inner surface of the retainer portion 13C can contact the surface of the side wall 12 on the opposite side of the roller 7. It is possible to prevent the shaft portion 13 from being displaced in its axial direction and falling off. In addition, since the retainer portion 13C has the same outer diameter as the shaft body 13A, it is passed through the shaft body threading portion 12A1 included in the shaft threading portion 12A during assembly. As a result, compared to the case where the retaining portion has an outer diameter larger than that of the shaft main body 13A, the opening range of the shaft through portion 12A can be kept small, and the mechanical strength of the main body portion 9 can be kept high. be suitable. In addition, it can be said that the shaft portion 13 has a configuration in which a pair of grooves are formed in a cylindrical body so that the diameter of the pair of supported portions 13B is locally reduced.

As shown in FIGS. 4 and 5, the shaft portion 13 has tapered surfaces 13A1 along the entire circumference at both ends in the axial direction of the peripheral surface of the shaft body 13A. Since such a tapered surface 13A1 is provided, when the shaft portion 13 and the roller bearing portion 16 are assembled to each other while being relatively displaced in the axial direction, the roller 16A is positioned at the end of the shaft body 13A in the axial direction. It is difficult to get caught on the part.

This embodiment has the structure as described above, and the assembly order will be described next. First, as shown in FIG. 7, the roller bearing portion 16 is attached to the roller 7 . Specifically, a plurality of rollers 16A are arranged along the inner peripheral surface of the roller 7 so as to be in contact with each other. At this time, a temporary assembly member (such as a rubber plug) having an outer diameter approximately equal to that of the shaft body 13A may be inserted inside the plurality of rollers 16A. The roller 7 assembled with the roller bearing portion 16 is arranged between the pair of side walls 12 of the body portion 9 . At this time, the rollers 7 are arranged so that the innermost surfaces (surfaces in contact with the temporary assembly members) of the plurality of rollers 16A are substantially flush with the peripheral surface of the shaft body through portion 12A1 of the shaft through portion 12A. preferably.

Subsequently, an operation of assembling the shaft portion 13 to the main body portion 9 is performed. The shaft portion 13 is passed through a shaft passing portion 12A provided on one of the pair of side walls 12 . At this time, the center (axial center) of the shaft portion 13 coincides with the center C1 of the peripheral surface of the shaft body through portion 12A1 of the shaft through portion 12A. In addition, when the temporary assembly member is assembled inside the plurality of rollers 16A, the temporary assembly member is pushed out by the shaft portion 13 passed through the shaft through portion 12A, and the shaft portion 13 is pushed inside the plurality of rollers 16A. will be inserted. When the shaft portion 13 is passed through the shaft through portion 12A provided on the other of the pair of side walls 12, and the pair of retainer portions 13C are arranged outside the pair of side walls 12, as shown in FIG. The supported portion 13B is surrounded by the peripheral surfaces of the shaft through portions 12A of the pair of side walls 12, and the shaft body 13A is arranged inside the plurality of rollers 16A. As a result, the roller bearing portion 16 is arranged between the shaft body 13A and the roller 7 . In this state, as shown in FIGS. 8 and 9, between the outer peripheral surface of the supported portion 13B and the peripheral surface of the shaft-through portion 12A, a gap is formed over the entire circumference, and the gap is the expanded portion. 12A2 is the maximum.

When the shaft portion 13 is displaced downward in the vertical direction with respect to the main body portion 9, the pair of supported portions 13B are aligned with the shaft through portions 12A of the pair of side walls 12 as shown in FIGS. It is supported by the peripheral surface of the extension 12A2. The amount of displacement of the shaft portion 13 at this time substantially matches the distance between the center C1 of the peripheral surface of the shaft body through portion 12A1 and the center C2 of the peripheral surface of the extended portion 12A2 (see FIG. 6). ). At this time, the center of the shaft portion 13 coincides with the center C2 of the peripheral surface of the extended portion 12A2 of the shaft through portion 12A. In this state, although the axial end faces of some of the rollers 16A included in the plurality of rollers 16A are exposed to the outside through the shaft through portions 12A, the exposed area is smaller than the total area of the end faces. That is, of the plurality of rollers 16A, the end faces of the rollers 16A facing the respective shaft-passing portions 12A are partly exposed to the outside, but the remaining end faces are formed by the edges of the respective shaft-passing portions 12A on the side walls 12. It is covered with a protective film to avoid exposure to the outside. Further, of the plurality of rollers 16A, the entire end surfaces of the remaining rollers 16A that do not face the respective shaft-through portions 12A are covered by the edge portions of the respective shaft-through portions 12A of the side walls 12. As shown in FIG. In this way, all the rollers 16A are sandwiched from the outside by the pair of roller holding portions 17 constituted by the edge portions of the respective shaft-passing portions 12A of the respective side walls 12, thereby preventing them from slipping out in the axial direction. , is maintained.

As described above, the rocker arm 6 of the present embodiment has a longitudinal shaft portion 13, a roller 7 rotatably attached to the shaft portion 13, and a pair of side walls 12 arranged to sandwich the roller 7. A pair of side walls 12 are interposed between the main body portion 9 and the shaft portions 13 and the rollers 7, in which the shaft portions 12A through which the shaft portions 13 are passed. and a roller bearing portion 16 composed of a plurality of rollers 16A arranged side by side. 13B, and the main body portion 9 has a shaft through portion 12A whose opening area is larger than the cross-sectional area of a cross-sectional surface perpendicular to the axial direction of the shaft portion 13 in the supported portion 13B, and a plurality of rollers 16A are connected to the shaft portion. A pair of roller holding portions 17 are provided to sandwich and hold rollers 13 from the outside in the axial direction.

With this configuration, the roller 7 sandwiched between the pair of side walls 12 of the main body 9 is supported by the shaft portion 13 so as to be rotatable. A roller bearing portion 16 composed of a plurality of rollers 16A arranged along the circumferential direction of the shaft portion 13 is interposed between the roller 7 and the shaft portion 13 to ensure smooth rotation of the roller 7. . The shaft portion 13 is passed through the shaft through portions 12A that are formed in the pair of side walls 12 of the body portion 9, respectively, and each supported portion 13B is supported by the peripheral surface of each shaft through portion 12A, so that the shaft portion 13 is rotatable. It is said that Since the shaft portion 13 is rotatable with respect to the main body portion 9, the load acting on the shaft portion 13 from the roller 7 via the roller bearing portion 16 is dispersed in the circumferential direction of the shaft portion 13, thereby 13 is less likely to be unevenly worn.

In the body portion 9, the opening area of the shaft through portion 12A is made larger than the cross-sectional area of the section perpendicular to the axial direction of the shaft portion 13 in the supported portion 13B, thereby assembling the shaft portion 13 to the body portion 9. Ease is guaranteed. However, there is a possibility that some of the rollers 16</b>A forming the roller bearing portion 16 may not be held by the pair of side walls 12 . On the other hand, when a retainer is used to hold a plurality of rollers 16A as in the conventional art, a plurality of grooves are formed on the circumferential surface of the cylindrical retainer at intervals in the circumferential direction. Since it is necessary to individually attach a plurality of rollers 16A to each other, there is a problem that workability is not good.

Therefore, if a configuration is adopted in which a plurality of rollers 16A arranged along the circumferential direction of the shaft portion 13 are sandwiched from the outside in the axial direction of the shaft portion 13 by a pair of roller holding portions 17, the opening area of the shaft through portion 12A can be reduced. Even if the cross-sectional area of the supported portion 13B is larger than the cross-sectional area perpendicular to the axial direction of the shaft portion 13, the plurality of rollers 16A can be appropriately held. Moreover, during assembly, the plurality of rollers 16A arranged along the circumferential direction of the shaft portion 13 in contact with each other may be sandwiched from the outside by a pair of roller holding portions 17 in the axial direction. As compared with the case where a plurality of rollers 16A are individually mounted in a plurality of grooves formed in the retainer, workability for assembly is improved.

The shaft portion 13 has a shaft body 13A in which a roller bearing portion 16 is interposed between the shaft portion 13 and the roller 7. The maximum opening diameter D1 of the shaft through portion 12A is larger than the maximum outer diameter D2 of the shaft portion 13 and the difference between the difference and the outer diameter D3 of the shaft main body 13A and the outer diameter D4 of the supported portion 13B. and the sum of is smaller than the outer diameter D5 of the roller 16A. First, since the shaft-passing portion 12A is formed in the side wall 12 in the shape of a hole surrounding the shaft portion 13, the shaft-passing portion is formed in the side wall 12 in the shape of a groove opening in one direction along the wall surface. As a result, the mechanical strength of the body portion 9 can be kept high. Moreover, by making the maximum opening diameter D1 of the shaft-through portion 12A larger than the maximum outer diameter D2 of the shaft portion 13, the ease of assembly of the shaft portion 13 to the shaft-through portion 12A is ensured. Furthermore, the sum of the difference between the maximum opening diameter D1 of the shaft through portion 12A and the outer diameter of the shaft portion 13 and the half of the difference between the outer diameter D3 of the shaft body 13A and the outer diameter D4 of the supported portion 13B is Since the outer diameter D5 of the rollers 16A is smaller than the outer diameter D5 of the rollers 16A, when the shaft portion 13 is passed through the shaft-passing portion 12A and the supported portion 13B is supported, the plurality of rollers 16A are positioned on the pair of side walls 12. It is sandwiched from the outside in the axial direction of the shaft portion 13 by the hole edge of the shaft through portion 12A. That is, since the hole edges of the shaft through portions 12A in the pair of side walls 12 constitute a pair of roller holding portions 17 that hold the plurality of rollers 16A, it is assumed that the pair of roller holding portions is provided as a separate part from the main body portion 9. The number of parts can be reduced as compared with the case where the parts are prepared.

In the shaft portion 13, the supported portion 13B has a smaller diameter than the shaft main body 13A. and an extended portion 12A2 formed by extending a part of the peripheral surface of 12A1 and supporting the supported portion 13B by the peripheral surface. In this way, the shaft portion 13 can be assembled to the main body portion 9 by passing the shaft body 13A of the shaft portion 13 through the shaft body passing portion 12A1 of the shaft passing portion 12A. . The supported portion 13B of the shaft portion 13 has a diameter smaller than that of the shaft main body 13A, and is formed by expanding a part of the peripheral surface of the shaft main body passing portion 12A1 of the shaft passing portion 12A. Since the peripheral surface supports the supported portion 13B, the peripheral surface of the extended portion 12A2 stabilizes the supported portion 13B in comparison with the case where the peripheral surface of the shaft body through portion 12A1 does not form the extended portion. can support.

Further, the body portion 9 is configured such that the peripheral surface of the extended portion 12A2 has an arcuate shape with the same radius of curvature as the outer peripheral surface of the supported portion 13B. In this way, the outer peripheral surface of the supported portion 13B comes into surface contact with the peripheral surface of the expanded portion 12A2, so that the supported portion 13B is more stably supported by the peripheral surface of the expanded portion 12A2. .

Further, the main body portion 9 is configured such that the peripheral surface of the shaft main body through portion 12A1 is along the outer peripheral surface of the shaft main body 13A. In this way, the opening range of the shaft body through portion 12A1 can be minimized to allow the shaft body 13A to pass therethrough. As a result, a decrease in the strength of the side wall 12 due to the opening of the shaft body through portion 12A1 in the side wall 12 is suppressed. The maximum opening diameter D1 of the shaft through portion 12A is the maximum opening diameter D1 across the shaft body through portion 12A1 and the extended portion 12A2, and the maximum outer diameter D2 of the shaft portion 13 is the outer diameter of the shaft main body 13A. Therefore, the difference between the maximum opening diameter D1 of the shaft through portion 12A and the maximum outer diameter D2 of the shaft portion 13 is approximately the size of the expanded portion 12A2 in the shaft through portion 12A.

Further, the shaft portion 13 has a pair of retainer portions 13C which are arranged to face the surfaces of the pair of side walls 12 opposite to the roller 7 and have the same outer diameter as the shaft body 13A. With this configuration, the pair of retaining portions 13C are arranged to face the surfaces of the pair of side walls 12 arranged to sandwich the roller 7 on the side opposite to the roller 7. It is possible to prevent the shaft portion 13 assembled to the main body portion 9 from being displaced in the axial direction and falling off. Moreover, since the retainer portion 13C has the same outer diameter as that of the shaft body 13A, it is passed through the shaft body threading portion 12A1 included in the shaft threading portion 12A during assembly. As a result, compared to the case where the retaining portion has an outer diameter larger than that of the shaft main body 13A, the opening range of the shaft through portion 12A can be kept small, and the mechanical strength of the main body portion 9 can be kept high. be suitable.

<Embodiment 2>
Embodiment 2 will be described with reference to FIGS. 10 to 14. FIG. In this second embodiment, the configuration of the body portion 109, the shaft portion 113 and the roller holding portion 117 is changed. Duplicate descriptions of the structures, functions and effects similar to those of the first embodiment will be omitted. Further, the same reference numerals are used for components having the same names as those of the above-described first embodiment, which appear in the explanation of this embodiment, and "100" is added to the reference numerals.

As shown in FIGS. 10 and 11, the main body portion 109 according to the present embodiment has a shaft-passing portion 112A formed in a groove shape opening along the wall surface of the side wall 112 in one direction. More specifically, the shaft through portion 112A has a U-shaped peripheral surface when viewed from the axial direction of the shaft portion 113, and the arc-shaped bottom portion of the peripheral surface supports the supported portion 113B of the shaft portion 113. can support. Since the peripheral surface of the shaft through portion 112A is open upward in the vertical direction, the shaft portion 113 can be passed through the shaft through portion 112A from above when assembling, so that the workability related to the assembling is good. It has become. On the other hand, in the main body portion 109, the opening area of the shaft through portion 112A is larger than the cross-sectional area of the section orthogonal to the axial direction of the shaft portion 113 in the supported portion 113B. For this reason, the plurality of rollers 116A arranged so as to surround the shaft body 113A of the shaft portion 113 over the entire circumference include rollers whose entire end faces are exposed to the outside through the shaft through portion 112A.

Therefore, as shown in FIGS. 10 and 11, the pair of roller holding portions 117 according to the present embodiment are separate parts from the main body portion 109 and the shaft portion 113, and the rollers 107 and the pair of side walls 112 are separated from each other. It is arranged so as to intervene between them. The pair of roller holding portions 117 are attached to the shaft portion 113 and arranged to sandwich the roller 107 and the roller bearing portion 116 from both sides in the axial direction of the shaft portion 113 . The shaft portion 113 has a pair of mounting portions 13D to which the pair of roller holding portions 117 are respectively mounted. The pair of mounting portions 13D are positioned between the shaft body 113A and the pair of supported portions 113B. The roller holding portion 117 has a circular plate-like outer shape, and the normal direction of the plate surface coincides with the axial direction of the shaft portion 113 . At the center of the roller holding portion 117, a mounting portion passage portion 17A through which the mounting portion 13D of the shaft portion 113 is passed is formed. The outer diameter of the roller holding portion 117 is approximately the same as the outer diameter of the roller 107 . In the roller holding portion 117 having such a configuration, the plate surface on the inner side (the side opposite to the side wall 112 side) faces and can contact the entire end surface of all the rollers 116A included in the roller bearing portion 116. be done. Therefore, the pair of roller holding portions 117 can firmly hold the plurality of rollers 116A regardless of the opening range of the shaft-passing portion 112A of the side wall 112. FIG.

As shown in FIG. 12, the mounting portion 13D and the mounting portion passing portion 17A have a non-circular peripheral surface when viewed from the axial direction of the shaft portion 113. As shown in FIG. More specifically, as shown in FIGS. 12 and 13, most of the peripheral surface of the mounting portion 13D is flush with the peripheral surface of the shaft main body 113A. side portion) is linear in the horizontal direction. The peripheral surface of the attaching portion passage portion 17A is formed along the peripheral surface of the attaching portion 13D, and has a linear portion along the horizontal direction. The pair of retainer portions 113C of the shaft portion 113 are also configured such that their circumferential surfaces are aligned with the circumferential surface of the mounting portion 13D. It is designed to be passed through the attaching portion passing portion 17A.

As shown in FIG. 11, when the roller holding portion 117 having such a configuration is attached to the mounting portion 13D, the peripheral surface of the mounting portion through portion 17A is in contact with the peripheral surface of the mounting portion 13D. is in contact with the roller 107 . Therefore, when the roller 107 is rotated with the rotation of the camshaft 3 (see FIG. 1), the shaft portion 113 of the roller holding portion 117 in contact with the roller 107 has a non-circular shape when viewed from the axial direction. Rotational force is transmitted from the circumferential surface of the through-hole portion 17A to the mounting portion 13D, which has a non-circular shape when viewed from the axial direction of the shaft portion 113. This rotational force promotes the rotation of the shaft portion 113. . That is, since the rotational force of the roller 107 can be used to rotate the shaft portion 113 by transmitting it to the shaft portion 113 via the roller holding portion 117, the shaft portion 113 can be rotated from the roller 107 via the roller bearing portion 116. The load acting on the shaft portion 113 is preferably distributed in the circumferential direction of the shaft portion 113 , thereby making uneven wear of the shaft portion 113 less likely to occur.

This embodiment has the structure as described above, and the assembly order will be described next. First, as shown in FIG. 12, the work of assembling the roller 107, the roller bearing portion 116 and the pair of roller holding portions 117 to the shaft portion 113 is performed. During this assembly, the plurality of rollers 116A are arranged along the inner peripheral surface of the roller 107 so as to be in contact with each other. At this time, a temporary assembled member (such as a rubber plug) having an outer diameter approximately equal to that of the shaft body 113A may be inserted inside the plurality of rollers 116A. In that state, the shaft portion 113 is passed through the inner side of the plurality of rollers 116A. At this time, if a temporary assembled member is assembled inside the plurality of rollers 116A, the temporary assembled member is pushed out by the shaft portion 113, and the shaft portion 113 is inserted inside the plurality of rollers 116A. After that, the pair of roller holding portions 117 are assembled to the pair of mounting portions 13D of the shaft portion 113 . The roller holding portion 117 is attached to the shaft portion 113 by passing the attachment portion 13D through the attachment portion passing portion 17A. In this state, the inner plate surface of the roller holding portion 117 is in contact with the end surface of the roller 107, and the peripheral surface of the mounting portion passing portion 17A is in contact with the peripheral surface of the mounting portion 13D over substantially the entire circumference. Thus, the roller bearing portion 116 , the roller 107 and the pair of roller holding portions 117 can be assembled to the shaft portion 113 prior to assembly to the main body portion 109 .

After that, an operation of assembling the shaft portion 113, to which the roller 107, the roller bearing portion 116 and the pair of roller holding portions 117 are assembled, to the main body portion 109 is performed. At the time of this assembly, as shown in FIG. It is passed through the opening of each shaft through portion 112A. When the portion to be supported 113B reaches the inner end of the shaft through portion 112A, the portion to be supported 113B is supported by the bottom surface of the shaft through portion 112A as shown in FIGS. Further, since the pair of retaining portions 113C can contact the outer plate surfaces of the pair of side walls 112, the shaft portion 113 can be retained from the main body portion 109. As shown in FIG. In this manner, the work of assembling the shaft portion 113 to the main body portion 109 can be easily performed.

As described above, according to this embodiment, the pair of roller holding portions 117 are arranged to be interposed between the roller 107 and the pair of side walls 112 . As described above, since the roller holding portions 117 are separate parts from the main body portion 109, the pair of roller holding portions 117 can hold a plurality of rollers regardless of the opening range of the shaft through portion 112A of the side wall 112. 116A can be held firmly.

Further, the main body portion 109 is formed in a groove shape in which the shaft through portion 112A opens along the wall surface of the side wall 112 in one direction. In this manner, when the shaft portion 113 is assembled to the main body portion 109, the shaft portion 113 can be passed through the groove-shaped shaft passing portion 112A of each side wall 112 along the opening direction thereof. Since the roller bearing portion 116, the roller 107 and the pair of roller holding portions 117 can be assembled to the shaft portion 113 prior to assembly to the main body portion 109, workability for assembly is improved. Become.

The shaft portion 113 has a mounting portion 13D to which the roller holding portion 117 is mounted. The mounting portion 13D has a non-circular shape when viewed from the axial direction of the shaft portion 113. A mounting portion passage portion 17A through which the mounting portion 13D is passed is formed with an opening, and the peripheral surface of the mounting portion passage portion 17A is formed in a non-circular shape when viewed from the axial direction of the shaft portion 113. is brought into contact with roller 107 . In this way, when the roller holding portion 117 is attached to the mounting portion 13D of the shaft portion 113, the mounting portion 13D is passed through the mounting portion passing portion 17A of the roller holding portion 117, and the roller holding portion 117 is It is in contact with roller 107 . Therefore, when the roller 107 is rotated, the axial line of the shaft portion 113 is projected from the peripheral surface of the mounting portion passage portion 17A, which is formed in a non-circular shape when viewed from the axial direction of the shaft portion 113, of the roller holding portion 117 in contact with the roller 107. Since the rotational force is transmitted to the mounting portion 13D which is non-circular when viewed from the direction, the rotational force promotes the rotation of the shaft portion 113. As shown in FIG. That is, since the rotational force of the roller 107 can be used to rotate the shaft portion 113 by transmitting it to the shaft portion 113 via the roller holding portion 117, the shaft portion 113 can be rotated from the roller 107 via the roller bearing portion 116. The load acting on the shaft portion 113 is preferably distributed in the circumferential direction of the shaft portion 113 , thereby making uneven wear of the shaft portion 113 less likely to occur. Further, since the roller holding portion 117 is configured to contact the roller 107, the function of holding the plurality of rollers 116A interposed between the roller 107 and the shaft portion 113 is highly reliably exhibited.

<Embodiment 3>
Embodiment 3 will be described with reference to FIGS. 15 to 17. FIG. In this third embodiment, the configurations of the shaft portion 213 and the roller holding portion 217 are changed from the above-described second embodiment. Duplicate descriptions of structures, functions and effects similar to those of the first and second embodiments described above will be omitted. Further, the same reference numerals are used for components having the same names as those of the first and second embodiments, which appear in the explanation of this embodiment, and "200" is added to the reference numerals.

A pair of roller holding portions 217 according to the present embodiment are provided integrally with the shaft portion 213 as shown in FIGS. 15 and 16 . More specifically, the shaft portion 213 has a pair of supported portions 213B larger in diameter than the shaft body 213A. Therefore, a space exists around the shaft main body 213A so as to be sandwiched in the axial direction by the pair of supported portions 213B. It has become. When the plurality of rollers 216A are housed in the space around the shaft body 213A, each roller 216A is sandwiched between the pair of supported portions 213B in the axial direction. That is, the pair of supported portions 213B constitute a pair of roller holding portions 217 that hold the plurality of rollers 216A. Therefore, compared with the case where a pair of roller holding portions are prepared as separate parts from the shaft portion 213, the number of parts can be reduced.

Further, the shaft portion 213 is configured such that half of the difference between the outer diameter of the supported portion 213B and the outer diameter of the shaft body 213A is smaller than the outer diameter D5 of the roller 216A. In this way, the roller 216A is partially covered from the outside in the axial direction by the roller holding portion 217 (supported portion 213B) on the end surface, but the remaining portion of the end surface is axially supported by the roller holding portion 217. It will be exposed to the outside without being covered from the outside. Accordingly, when the rollers 216A are assembled in the space between the shaft body 213A of the shaft portion 213 and the roller 207, the rollers 216A can be easily accommodated in the space. can be It should be noted that the body portion 209 is similar to the second embodiment described above in that the shaft through portion 212A is formed in a groove shape opening along the wall surface in one direction on the side wall 212 .

This embodiment has the structure as described above, and the assembly order will be described next. First, as shown in FIG. 17, the work of assembling the roller 207 and the roller bearing portion 216 to the shaft portion 213 is performed. During this assembly, the rollers 207 are temporarily assembled to the shaft body 213A of the shaft portion 213, and the plurality of rollers 216A are housed in the space provided between the shaft body 213A and the rollers 207. As shown in FIG. At this time, the step of the supported portion 213B rising from the peripheral surface of the shaft body 213A (half the difference between the outer diameter of the supported portion 213B and the outer diameter of the shaft body 213A) becomes smaller than the outer diameter D5 of the roller 216A. Therefore, it is easy to accommodate the roller 216A. The accommodated roller 216A is held by being sandwiched from both sides in the axial direction by a pair of supported portions 213B (roller holding portions 217). Thus, the roller bearing portion 216 and the roller 207 can be assembled to the shaft portion 213 prior to assembly to the main body portion 209 .

After that, an operation of assembling the shaft portion 213 to which the roller 207 and the roller bearing portion 216 are assembled to the main body portion 209 is performed. For this assembly, as shown in FIG. It is passed through the opening of each shaft through portion 212A. When the portion to be supported 213B reaches the inner end of the shaft through portion 212A, as shown in FIGS. 15 and 16, the portion to be supported 213B is supported by the bottom surface of the shaft through portion 212A. In addition, since the pair of retaining portions 213C can come into contact with the outer plate surfaces of the pair of side walls 212, the shaft portion 213 is prevented from detaching from the main body portion 209. As shown in FIG. In this manner, the work of assembling the shaft portion 213 to the main body portion 209 can be easily performed.

As described above, according to the present embodiment, the body portion 209 has the shaft-passing portion 212A formed in a groove shape opening along the wall surface of the side wall 212 in one direction. It has a shaft body 213A between which a roller bearing portion 216 is interposed. A pair of roller holding portions 217 are configured by being smaller than the outer diameter D5 of the roller 216A. With this configuration, the outer diameter of the pair of supported portions 213B is made larger than the outer diameter of the shaft body 213A, so that the roller bearing portions 216 interposed between the shaft body 213A and the roller 207 are formed. The rollers 216A are arranged to face the side surfaces of the pair of supported portions 213B. That is, the plurality of rollers 216A are sandwiched from the outside in the axial direction of the shaft portion 213 by the pair of supported portions 213B, and the pair of supported portions 213B hold the rollers 216A. configure. Therefore, compared with the case where a pair of roller holding portions are prepared as separate parts from the shaft portion 213, the number of parts can be reduced. Moreover, half of the difference between the outer diameter of the supported portion 213B and the outer diameter of the shaft body 213A is smaller than the diameter of the rollers 216A. Workability is improved when assembling. Further, when the shaft portion 213, to which the roller 207 and the roller bearing portion 216 are previously assembled, is assembled to the main body portion 209, the shaft portion 213 is inserted along the opening direction of the groove-shaped shaft through portion 212A. Just let it pass.

<Other embodiments>
The technology disclosed in the present specification is not limited to the embodiments described by the above description and drawings, and includes the following embodiments, for example.

(1) In the configuration described in Embodiment 1, the axial portion 12A may not have the extended portion 12A2. In that case, the specific shape of the shaft through portion 12A viewed from the axial direction of the shaft portion 13 can be changed as appropriate, and may be, for example, a perfect circle, an ellipse, an oval, or a non-circular shape (square, trapezoid, etc.). There may be.

(2) In the configuration described in the first embodiment, the specific shape of the peripheral surface of the shaft body through portion 12A1 viewed from the axial direction of the shaft portion 13 can be changed as appropriate. It may be non-circular (rectangular, trapezoidal, etc.).

(3) In the configuration described in Embodiment 1, the specific shape of the peripheral surface of the extension portion 12A2 as viewed from the axial direction of the shaft portion 13 can be changed as appropriate, such as elliptical, oval, and non-circular. (square, trapezoid, etc.).

(4) In the configuration described in Embodiment 1, the radius of curvature of the peripheral surface of the extended portion 12A2 that constitutes the shaft through portion 12A may be larger or smaller than the radius of curvature of the peripheral surface of the supported portion 13B. .

(5) In the configuration described in the first embodiment, the size (opening range) of the extended portion 12A2 can be appropriately changed other than illustrated. As long as the end surface of the roller 16A facing the shaft through portion 12A and the roller holding portion 17 (the edge portion of the shaft through portion 12A of the side wall 12) are kept in contact with each other, the size of the enlarged portion 12A2 can be appropriately adjusted. can be changed to

(6) In the configurations described in Embodiments 1 and 2, the outer diameter of the retaining portions 13C and 113C may be larger or smaller than the outer diameter of the shaft bodies 13A and 113A.

(7) In the configuration described in Embodiment 2, the specific shape of the mounting portion through portion 17A viewed from the axial direction of the shaft portion 113 can be changed as appropriate. It may be non-circular (rectangular, trapezoidal, etc.). Also, the mounting portion through portion 17A may be of a size that allows the shaft main body 113A to pass therethrough. , the assembly procedure can be the same as in the first embodiment.

(8) In the configurations described in Embodiments 2 and 3, the specific shape of the shaft through portions 112A and 212A viewed from the axial direction of the shaft portions 113 and 213 can be changed as appropriate. For example, the open ends of the shaft-passing portions 112A and 212A may widen in a tapered shape.

(9) The shaft portions 13, 113, and 213 may be configured such that the difference between the outer diameter of the shaft bodies 13A, 113A, and 213A and the outer diameter of the supported portions 13B, 113B, and 213B is zero.

(10) The shaft portions 13, 113, 213 may be configured without the retaining portions 13C, 113C, 213C. In that case, the outer diameter of the shaft portion 13, 113, 213 may be constant over the entire length.

6 Rocker arm 7,107,207 Roller 9,109,209 Main body 12,112,212 Side wall 12A, 112A, 212A Shaft through part 12A1 Shaft main body through part 12A2 Extended part , 13, 113, 213... Shaft portion 13A, 113A, 213A... Shaft main body 13B, 113B, 213B... Supported portion 13C, 113C, 213C... Retaining portion 13D... Mounting portion 16, 116, 216... Roller bearing portion 16A, 116A, 216A Roller 17, 117, 217 Roller holding portion 17A Mounting portion through portion D1 Maximum opening diameter D2 Maximum outer diameter D3 Outer diameter D4 Outer diameter , D5... Outer diameter

Claims (10)

an elongate shaft;
a roller rotatably attached to the shaft;
a main body portion having a pair of side walls arranged to sandwich the roller and having openings formed in the pair of side walls so as to allow the shaft portion to be passed therethrough;
a roller bearing portion interposed between the shaft portion and the roller and configured by a plurality of rollers arranged along the circumferential direction of the shaft portion;
The shaft portion has a pair of supported portions that are rotatably supported by the peripheral surface of the shaft through portion of the pair of side walls,
In the main body portion, the opening area of the shaft through portion is larger than the cross-sectional area of the section perpendicular to the axial direction of the shaft portion in the supported portion,
A rocker arm comprising a pair of roller holding portions that hold the plurality of rollers by sandwiching them from the outside in the axial direction. The shaft portion has a shaft body in which the roller bearing portion is interposed between itself and the roller,
The main body portion has the shaft through portion formed in the side wall in the shape of a hole surrounding the shaft portion, and the maximum opening diameter of the shaft through portion is larger than the maximum outer diameter of the shaft portion and the difference therebetween, The sum of the difference between the outer diameter of the shaft main body and the outer diameter of the supported portion is smaller than the outer diameter of the roller,
2. The rocker arm according to claim 1, wherein the pair of roller holding portions are formed by hole edges of the shaft-passing portions in the pair of side walls. In the shaft portion, the supported portion has a diameter smaller than that of the shaft body,
In the main body portion, the shaft through portion is formed by extending a shaft through portion through which the shaft main body is passed and a part of the peripheral surface of the shaft through portion, and the portion to be supported is supported by the peripheral surface of the shaft through portion. 3. The rocker arm of claim 2, configured to include: an extension that 4. The rocker arm according to claim 3, wherein the body portion is configured such that the peripheral surface of the extended portion has an arcuate shape with the same radius of curvature as the outer peripheral surface of the supported portion. 5. The rocker arm according to claim 3, wherein the body portion is configured such that the peripheral surface of the shaft body through portion is along the outer peripheral surface of the shaft body. 6. The shaft portion according to claim 5, wherein the shaft portion has a pair of retainer portions which are disposed so as to face surfaces of the pair of side walls opposite to the roller and which have the same outer diameter as the shaft body. rocker arm. 2. The rocker arm according to claim 1, wherein said pair of roller holding portions are arranged so as to be interposed between said roller and said pair of side walls. 8. A rocker arm according to claim 7, wherein said main body portion is formed in the shape of a groove opening in one direction along said wall surface of said side wall. The shaft portion has a mounting portion to which the roller holding portion is mounted,
The mounting portion has a non-circular shape when viewed from the axial direction,
The roller holding portion has an opening formed with a mounting portion passage portion through which the mounting portion is passed, and a peripheral surface of the mounting portion passage portion has a non-circular shape when viewed from the axial direction,
9. A rocker arm according to claim 7, wherein said roller holding portion is in contact with said roller. The main body part is formed in a groove shape in which the shaft through part opens in one direction along the wall surface of the side wall,
The shaft portion has a shaft body in which the roller bearing portion is interposed between itself and the roller,
The pair of supported portions has a diameter larger than that of the shaft body, and half of the difference from the outer diameter of the shaft body is smaller than the outer diameter of the rollers, thereby forming the pair of roller holding portions. The rocker arm of claim 1, comprising:

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