KR20140015562A - Cam follower device - Google Patents

Abstract

SUMMARY OF THE INVENTION An object of the present invention is to provide a cam follower device that is excellent in all of durability, assemblability, and design freedom, and can be reduced in size and weight, and can reduce manufacturing cost. Both ends of the support shaft 3a are supported by the support wall portions 12b and 12c so as to be capable of relative rotation, while being inserted through the support holes 15b and 15c of the support wall portions 12b and 12c. On the outer circumferential surface of the axial middle portion of the support shaft 9a, the inner ring ₁₆ whose outer diameter D ₁₆ is larger than the inner diameter d ₁₅ of the support holes 15b and 15c can be rotated together with the support shaft 9a. Insert it. Further, a plurality of cylindrical rollers 13 are provided between the inner ring raceway 17 formed on the outer circumferential surface of the inner ring 16 and the outer ring raceway 18 formed on the inner circumferential surface of the tappet roller 8b provided on the outer diameter side of the inner ring 16. Place it electrically.

Description

Cam follower device {CAM FOLLOWER DEVICE}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cam follower device that is assembled to a mechanism such as an engine for automobiles.

As a valve device for transmitting a movement of a cam fixed to a cam shaft rotating in synchronism with an engine crankshaft to a valve, disclosed in Japanese Unexamined Patent Application Publication Nos. 2006-183856 and 2005-326023. Cam follower devices are widely used. 12 and 13 show a first example of the conventional structure of the cam follower device described in Japanese Laid-Open Patent Publication No. 2006-183856. The rocker arm 1, which is the main body of the cam follower, is formed by the rocker shaft 3 inserted through the shaft hole 2 formed in the middle portion of the longitudinal direction (left and right directions in FIG. 12). It is rotatably supported by a cylinder head (not shown). Moreover, by screwing the adjustment bolt 4 in the screw hole formed in the base end part (left end part in FIG. 12) of the rocker arm 1, and tightening the lock nut 5, The adjustment bolt 4 is fixed to the base end of the rocker arm 1. And the base end surface (in FIG. 12) of the engine valve 6 which is an intake valve or an exhaust valve supported by the cylinder head reciprocally by the front end surface (lower end surface in FIG. 12) of the adjustment bolt 4 is shown. Top surface). The engine valve 6 is always pressurized by the return spring 7 in the opening direction (contact direction with the adjustment bolt 4). Therefore, the rocker arm 1 is provided with clockwise elasticity centering on the rocker shaft 3 in FIG.

On the other hand, the tappet roller 8 is rotatably supported through the support shaft 9 at the tip end (right end in FIG. 12) of the rocker arm 1, and the outer peripheral surface of the tappet roller 8 is supported. The outer circumferential surface of the cam 10 is brought into contact with the elasticity of the return spring 7. The cam 10 is integrally formed with the camshaft 11 which rotates in association with a crankshaft (not shown), and is rotatably supported by the cylinder head. By this structure, rotation of the camshaft 11 is converted into the reciprocating rocking motion of the rocker arm 1 centering on the rocker shaft 3, and the engine valve 6 is further changed by the rocker arm 1, The return spring 7 is reciprocated in the axial direction against the elasticity or based on the elasticity. Then, the opening and closing operation of the intake port or the exhaust port provided at the top of the cylinder of the engine is performed.

In such a side device, the part which rotatably supports the tappet roller 8 with respect to the rocker arm 1 via the support shaft 9 is comprised as shown in FIG. The support shaft 9 is crossed between the pair of support wall portions 12 provided parallel to each other at the distal end portion of the rocker arm 1. Then, the tappet roller 8 is attached to a plurality of cylindrical rollers (needles) 13 around a portion located between the inner surfaces of the support wall portion 12 at the middle of the support shaft 9. It is rotatably supported by the radial roller (needle) bearing 14 comprised by this. Both ends of the support shaft 9 are fitted and supported by circular support holes 15 provided concentrically with each other in the support wall 12. In such a state, the support shaft is plastically deformed at both ends of the outer periphery of the support shaft 9 by contacting the tip edges of the crimping jig such as a punch to the vicinity of the outer diameter of both end faces of the support shaft 9. (9) is firmly fixed to the support hole 15. Moreover, the structure, such as the single roller type which abbreviate | omits the radial roller bearing 14 and the double roller type etc. which provided the cylindrical member rotatably between the inner peripheral surface of a tappet roller and the outer peripheral surface of a support shaft, can also be employ | adopted. Since this structure is described in Unexamined-Japanese-Patent No. 2005-326023, detailed description is abbreviate | omitted.

In the first example of the conventional structure shown in Figs. 12 and 13, the longitudinal middle part of the rocker arm 1 is a point, and the tappet roller 8 and the engine valve 6 are driven at both ends. The adjusting bolt 4 is provided. In contrast, Japanese Laid-Open Patent Publication No. 2009-79569 discloses a support shaft fixed to an intermediate portion of the rocker arm 1a in the longitudinal direction (left and right directions in FIGS. 14 and 15) as shown in FIGS. A structure in which the tappet roller 8a is rotatably supported by the radial roller bearing 14 is described around 9a). Both ends of the support shaft 9a are also fitted into and supported by a circular support hole 15a provided concentrically with each other on the pair of support wall portions 12a. In the second example of such a conventional structure, in an assembled state to the engine, a lash adjuster serving as a point on one side (lower surface of the left end in FIGS. 14 and 15) of the rocker arm 1a is a point. ), The proximal end surface of the engine valve is brought into contact with one side (lower surface of the right end in FIGS. 14 and 15) of the other end.

In any structure, the outer peripheral surface of the middle portion of the support shaft 9 (9a) serves as an inner raceway of the radial roller bearing 14 for rotatably supporting the tappet roller 8 (8a). Since it has a role, it is not desirable to cause damage or the like on the outer peripheral surface of the intermediate portion. Therefore, the structure in which the support shaft 9 (9a) is pushed into the support hole 15 (15a) formed in the support wall portion 12 (12a) is disadvantageous in terms of damage prevention. Therefore, in order to prevent damage to the outer peripheral surface of the intermediate portion of the support shaft 9 (9a), the whole support shaft 9 (9a) is heated and then immersion quenching which is immersed in the quenching oil. Thereby, hardening the whole support shaft 9 (9a) is performed. However, in the case of immersion quenching, since the whole support shaft 9 (9a) hardens, both ends of the support shaft 9 (9a) are crimped when crimping both ends of the support shaft 9 (9a). The tip end of the jig, such as a punch to press, is damaged or the like and frequently needs to be replaced. As a result, the machining cost increases, which may invite an increase in the manufacturing cost of the cam follower device.

In response to this problem, hardening only the outer peripheral surface of the intermediate portion by high-frequency quenching, while leaving untreated portions (non-quenched portions) at both ends of the support shaft 9 (9a). However, high frequency quenching itself raises a machining cost. Moreover, even if both ends of the support shaft 9 (9a) are not treated, the durability of the jig used for the crimping of both ends is limited and does not lead to a reduction in the processing cost. It does not come until it is possible to sufficiently suppress the manufacturing cost of the follower device.

Moreover, in the cam follower apparatus of the conventional structure, as a radial roller bearing 14 provided between the inner peripheral surface of the tappet roller 8 (8a) and the outer peripheral surface of the intermediate part of the support shaft 9 (9a), the load capacity is secured. For this purpose, a total roller bearing that does not have a retainer is often used. When assembling the cam follower device having such a structure, first, in the space between the inner circumferential surface of the tappet roller 8 (8a) and the outer circumferential surface of the shaft member [stopper stopper] arranged on the inner diameter side of the tappet roller 8 (8a). And a roller assembly in which a plurality of cylindrical rollers are arranged.

Next, the roller assembly aligns both end faces of the stopper stopper between the widthwise inner surfaces of the support wall portion 12 (12a) and the support holes 15 (15a) of the support wall portion 12 (12a). Place in state. Next, the support shaft 9 (9a) is placed in the support hole 15 (15a) of one of the support wall portions 12 (12a) of the support wall portions 12 (12a), and the one support wall portion 12 (12a). ] Is inserted from the outside in the width direction. Next, while pushing the stopper by the support shaft 9 (9a), the support shaft 9 (9a) has its one end supported by the support hole 15 (15a) of the other support wall portion 12 (12a). Press in until it is inserted into]. In addition, both ends of the support shaft 9 (9a) are crimped. In this state, the support shaft 9 (9a) is supported in a state in which relative rotation is prevented with respect to the support wall portion 12 (12a). In such a structure, it is troublesome to insert the support shaft 9 (9a) on the inner diameter side of the tappet roller 8 (8a) while pushing the stopper. In addition, the use of the stopper increases the number of parts and the number of assembly times of the assembly equipment, thereby increasing the cost.

In addition, the outer diameter of the support shaft 9 (9a) and the inner diameter of the support hole 15 (15a) of the support wall portion 12 (12a) are the same as those of the cylindrical roller 13 constituting the radial roller bearing 14. Determined based on the diameter of the inscribed circle. For this reason, the freedom of design regarding the support shaft 9 (9a) and the support wall part 12 (12a) is low. In addition, when the diameter of the inscribed circle of the cylindrical roller 13 constituting the radial roller bearing 14 is large, it is necessary to increase the outer diameter of the entire support shaft 9 (9a) in order to correspond to the diameter of the inscribed circle. . For this reason, there is a possibility that the weight becomes heavy. In addition, since the support shaft 9 (9a) is supported in a state in which relative rotation is prevented with respect to the support wall portion 12 (12a), the load winding of the support shaft 9 (9a) is constant. It is limited in scope. That is, the radial load acting at the time of use is always loaded (supported) at the same position in the support shaft 9 (9a). As a result, a cyclic load is applied to the part which loads the radial load of the support shaft 9 (9a), and durability may fall. In addition, all the above-mentioned prior art documents shall be integrated in this specification by reference.

Japanese Unexamined Patent Publication No. 2006-183856 Japanese Unexamined Patent Publication No. 2005-326023 Japanese Unexamined Patent Publication No. 2009-79569

SUMMARY OF THE INVENTION In view of the above circumstances, the present invention is excellent in all of durability, assemblability, and design freedom, and it is possible to reduce the size and weight of the cam follower device and to reduce the manufacturing cost. The aim is to realize.

The cam follower device of the present invention includes a rocker arm, a support shaft, an inner ring equivalent member, and a tappet roller. Among them, the rocker arm has a pair of support wall portions provided at intervals from each other, and a pair of support holes formed at positions where these support wall portions are matched with each other, and is fixed to a cam shaft rotating in synchronization with the crankshaft of the engine. It is provided to face the cam, and is configured to receive a movement of the cam and to oscillate. Moreover, the said support shaft is supported by these support wall parts by crossing between the said pair of support wall parts in the state which inserted the both ends into the said pair of support holes. The inner ring equivalent member has an outer diameter that is larger than the inner diameter of the support hole, and is fitted in an interference fit on the axial middle portion of the support shaft in a state in which relative rotation with respect to the support shaft is prevented. . Moreover, the said tappet roller is arrange | positioned around the said inner ring equivalent member so that relative rotation with respect to this inner ring equivalent member is possible.

It is preferable that both ends of the support shaft are fitted in the pair of support holes by a gap fitting to enable rotation inside the support holes. Moreover, it is preferable to provide a radial roller bearing between the inner peripheral surface of the said tappet roller and the outer peripheral surface of the said inner ring equivalent member. In this case, it is preferable that this radial roller bearing is comprised by the total roller bearing which does not provide holding.

When the radial roller bearing is constituted by a total roller bearing, a pair of washers each having a circular ring shape are formed in a state in which the openings at both ends of the bearing space of the radial roller bearing are closed in the widthwise inner side of the support wall portion. It is desirable to provide. In this case, the outer diameter of these washers is made larger than the dimension with respect to the height direction of the said support wall part.

As the structure of the cam follower device of the present invention, a double roller type structure in which the inner circumferential surface of the tappet roller and the outer circumferential surface of the inner ring equivalent member are in sliding contact may be adopted. In this case, it becomes functionally the same as the single roller type. Alternatively, a triple roller type structure may be adopted between the inner circumferential surface of the tappet roller and the outer circumferential surface of the inner ring equivalent member, wherein the cylindrical member is disposed so as to allow relative rotation with respect to the tappet roller and the inner ring equivalent member. In this case, it is functionally the same as the double roller type.

According to the present invention, a structure of a cam follower device that is excellent in all of durability, assemblability, and freedom of design, which can be reduced in size and weight, and can be reduced in manufacturing cost.

The improvement of durability is aimed at by performing the quenching process by immersion hardening on the whole support shaft. In this invention, since it is not necessary to crimp both ends of a support shaft, hardening of a support shaft can be performed by immersion hardening. As a result, it is possible to sufficiently secure the strength and rigidity of the entire support shaft and effectively prevent plastic deformation based on the radial load received by the support shaft.

In addition, when a support shaft is supported in the state which can be rotated relative to a support wall part, the load winding of a support shaft is not restrict | limited to a fixed range. As a result, the repetitive load can be prevented from being applied to the same position of the support shaft, and the life of the support shaft can be extended.

Moreover, even when the radial roller bearing is constituted by the total roller bearing, by providing a pair of circular ring-shaped washers, the widthwise inner surface of the supporting plate portion is prevented from being worn by friction with the cylindrical roller. Therefore, the life of the support wall can be extended.

In addition, by reducing the dimension of the support wall in the height direction of the support wall, it is possible to reduce the area of the overlapping portion in the axial direction of the widthwise inner surface of the support wall and the axial end faces of the tappet roller. It becomes possible, and lubricating oil becomes easy to enter into the internal space (bearing space) of a radial roller bearing from the outside. For this reason, the service life of a cam follower apparatus can be apply | coated.

The improvement of assembly property is aimed at by providing an inner ring equivalent member. That is, one side of the support shaft is arranged in a state in which a roller assembly in which an inner ring equivalent member, a tappet roller, and other structural members (for example, a cylindrical roller constituting a radial roller bearing) is assembled is disposed between the supporting walls. It can be assembled by penetrating and inserting in the order of the support hole of the support wall part, the inner peripheral surface of the inner ring equivalent member, and the support hole of the other support wall part. For this reason, as in the conventional structure, the stopper placed on the inner diameter side of the tappet roller is pushed out by the support shaft, thereby eliminating the need for insertion.

The improvement of the degree of freedom of design is also aimed at by providing an inner ring equivalent member. That is, the outer diameter of the inner ring equivalent member can correspond to the diameter of the inscribed circle of the cylindrical roller of the radial roller bearing, and the inner diameter of the inner ring equivalent member can be appropriately set corresponding to the outer diameter of the support shaft and the inner diameter of the support hole of the support wall.

Miniaturization and weight reduction are also achieved by providing an inner ring equivalent member. That is, since the outer diameter of a support shaft can be made small by changing the inner diameter of an inner ring equivalence member, a support wall part is made around the support hole of a support wall part, ensuring a constant width dimension with respect to the radial direction of a support hole, The dimension with respect to the height direction of a support wall part can be made small. As a result, it is possible to miniaturize and reduce the weight of the support wall portion, and further, the entire rocker arm, while ensuring the desired rigidity.

In addition, when a pair of circular ring washers is provided, the cylindrical rollers constituting the radial roller bearing can be prevented from escaping in the axial direction from the bearing space by these washers. It is possible to further reduce the dimensions.

The reduction of the manufacturing cost is aimed at the necessity of the crimping work being unnecessary, the quenching treatment of the support shaft by immersion quenching, and the need for stopping stopper.

BRIEF DESCRIPTION OF THE DRAWINGS The figure corresponding to the AA cross section of FIG. 12 or the BB cross section of FIG. 14 which shows the 1st example of embodiment of this invention.
2 is a view similar to FIG. 1, showing a second example of embodiment of the present invention;
3 is a view similar to FIG. 1, showing a third example of the embodiment of the present invention;
4 is a view similar to FIG. 1, showing a fourth example of an embodiment of the present invention;
5 is a view seen from the side of FIG. 4;
FIG. 6 is a view similar to FIG. 1, showing a fifth example of embodiment of the present invention; FIG.
FIG. 7 is a view seen from the side of FIG. 6;
8 is a view similar to FIG. 1, showing a sixth example of embodiment of the present invention;
9 is a view seen from the side of FIG. 8;
10 is a view similar to FIG. 1, showing a seventh example of embodiment of the present invention;
FIG. 11 is a view seen from the side of FIG. 10;
12 is a side view showing a first example of a cam follower device of the conventional structure;
FIG. 13 is an enlarged CC sectional view of FIG. 12; FIG.
14 is a side view showing a second example of a cam follower device of the conventional structure;
15 is a view from above of FIG. 14;

[First Example of Embodiment]

1 shows a first example of embodiment of the present invention. Including this example, the features of the cam follower device of the present invention are the support structures for the support walls 12b, 12c of the support shaft 9b, and the inner ring equivalent member between the support shaft 9b and the tappet roller 8b. It is in the point which provided the phosphorus inner ring 16. Since the structure of the cam follower apparatus other than the characteristic part of this invention, and the assembly state to the engine are substantially the same as the conventional structure, including the structure shown in FIGS. 12-15, these description is abbreviate | omitted or simplified The following description will focus on the features of the present example.

The cam follower device of this example includes a rocker arm 1b, a support shaft 9b, an inner ring 16 that is an inner ring equivalent member, a tappet roller 8b, and a plurality of cylindrical rollers 13. The rocker arm 1b is provided with a pair of support wall portions 12b and 12c provided in a state where they are spaced apart from each other, and a pair of support holes 15b and 15c are provided at positions where these support wall portions 12b and 12c are matched with each other. ) Is formed. In the case of the cam follower apparatus of this example, the both ends of the forced hollow or solid support shaft 9b are penetrated into the support holes 15b and 15c of the forced support wall portions 12b and 12c through a minute gap (gap). By fitting, the support shaft 9b is supported between the support wall portions 12b and 12c so as to be relatively rotatable to the support wall portions 12b and 12c. That is, the outer diameter D ₉ of the support shaft 9b is slightly smaller than the inner diameter d ₁₅ of the support holes 15b and 15c (D _9). <d ₁₅ ).

The support shaft 9b hardens the whole by immersion quenching which is immersed in oil for quenching after heating the entire support shaft 9b in order to sufficiently secure the strength and rigidity of the entire support shaft 9b. . However, although the processing cost rises rather than the quenching by immersion quenching, only the outer peripheral surface of the intermediate part can be hardened by high frequency quenching, leaving untreated portions at both ends of the support shaft 9b. In addition, the hardening treatment such as quenching is performed on the inner circumferential surfaces of the support holes 15b and 15c, thereby causing damage such as wear to the sliding contact portions of the inner circumferential surfaces of the support holes 15b and 15c and the outer circumferential surfaces of both ends of the support shaft 9b. Can also be prevented. Further, an annular slip bearing member may be provided between the outer circumferential surfaces of both ends of the support shaft 9b and the inner circumferential surfaces of the support holes 15b and 15c. On the other hand, in this example, the support wall portions 12b, 12b, are press-fitted into the support holes 15b and 15c of the support wall portions 12b and 12c (fitting inwardly with an interference fit). It is also possible to adopt the structure which prevented rotation of the support shaft 9b with respect to 12c).

On the outer circumferential surface of the axial middle part of the support shaft 9b, the cylindrical inner ring 16 is restrained in a state in which relative rotation with respect to the support shaft 9b is prevented (rotable with the support shaft 9b). Fitted by fit. The outer diameter D ₁₆ of the inner ring 16 is larger than the inner diameter d ₁₅ of the support holes 15b and 15c (D ₁₆ > d ₁₅ ). In this way, the axial direction fall prevention of the support shaft 9b with respect to the support wall parts 12b and 12c is aimed at. Moreover, it is also possible to protrude the axial middle part of a support shaft radially, to provide a large diameter part, and to function the large diameter part of a support shaft as an inner ring equivalent member.

An inner ring raceway 17 is formed on the outer circumferential surface of the inner ring 16. Moreover, the tappet roller 8b is arrange | positioned around the inner ring 16 (outer diameter side) so that relative rotation with respect to the inner ring 16 and relative rotation with respect to the inner ring 16 is possible. Moreover, the outer ring raceway 18 is formed in the inner peripheral surface of the tappet roller 8b. And the radial roller bearing 14a is comprised by arrange | positioning the some cylindrical roller 13 so that rotation is possible between the inner ring raceway 17 and the outer ring raceway 18. As shown in FIG. In addition, in this example, although the radial roller bearing 14a is comprised by the total roller bearing which does not provide a holding | maintenance, it is also possible to use the cylindrical roller which has a holding | maintenance as a cylindrical roller.

When assembling the cam follower device of this example, first, a plurality of cylindrical rollers are provided in the space (bearing space 21) between the inner circumferential surface of the tappet roller 8b and the outer circumferential surface of the inner ring 16 provided on the inner diameter side of the tappet roller 8b. The roller assembly 19 which arrange | positioned (13) is assembled. Next, the roller assembly 19 is formed between the axial end portions of the inner circumferential surface of the inner ring 16 and the support holes of the support wall portions 12b and 12c between the widthwise inner surfaces of the support wall portions 12b and 12c. It arrange | positions in the state which matched 15b, 15c). Next, the support shaft 9b is inserted into the support hole 15b of one of the support wall portions 12b and 12c from the widthwise outer side of the support wall portion 12b. Further, the support shaft 9b is supported by the other end thereof (the left end in FIG. 1) while the support shaft 9b is press-fitted into the inner circumferential surface of the inner ring 16. It presses in until it inserts into the support hole 15c of the wall part 12c. In such a state, a minute gap is provided between the outer circumferential surface of both ends of the support shaft 9b and the inner circumferential surface of the support holes 15b and 15c of the support walls 12b and 12c. In addition, the direction of assembling the support shaft 3a may be reversed.

In the cam follower device of this example, the durability is secured by performing quenching by immersion quenching on the entire support shaft 9b. That is, when the cam follower unit of the invention, the support wall portion (12b, 12c) supporting hole (15b, 15c) by increasing the outer diameter (D ₁₆₎ of the inner ring 16 than the inner diameter (d _15), of the support of the The shaft 9b is prevented from falling out in the axial direction with respect to the supporting wall portions 12b and 12c. Therefore, it is not necessary to crimp both ends of the support shaft 9b, and it is not necessary to leave the both ends of the support shaft 9b untreated (the state that hardening is not performed). For this reason, hardening of the support shaft 9b can be performed by immersion hardening which is immersed in the oil for hardening after heating the whole. As a result, since the strength and rigidity of the whole support shaft 9b can fully be secured, plastic deformation based on the radial load which the support shaft 9b receives at the time of use can be effectively prevented.

In the cam follower device of the present example, the support shaft 9b is supported in a state in which relative rotation is possible with respect to the support walls 12b and 12c. For this reason, the load winding of the support shaft 9b is not limited to a fixed range. That is, at the time of use, the position of the support shaft 9b which loads a radial load does not always become the same. As a result, the repetitive load can be prevented from being applied at the same position of the support shaft 9b, and the life of the support shaft 9b can be extended.

In the cam follower device of the present example, the assembly performance is improved by providing the inner ring 16. That is, in the state which arrange | positioned the roller assembly 19 between support wall parts 12b and 12c, the support shaft 9b is the support hole 15b of the one support wall part 12b, and the inner peripheral surface of the inner ring 16. Can be assembled by inserting through the supporting holes 15c of the other supporting wall portion 12c in the order. Therefore, as in the conventional structure, the work of inserting the stopper placed on the inner diameter side of the tappet roller 8 (8a) (see Figs. 12 to 15) by pushing the support shaft 9 (9a) is inserted. It becomes unnecessary.

In the cam follower device of the present example, the degree of freedom of design is also improved by providing the inner ring 16. That is, in the case of the conventional structure, the outer diameter of the support shaft 9 (9a) and the support wall part 12 (12a) are supported by the diameter of the inscribed circle of the cylindrical roller 13 constituting the radial roller bearing 14. The inner diameter of the hole 15 (15a) is restricted. On the other hand, in the present invention, the outer diameter D ₁₆ of the inner ring 16 corresponds to the diameter of the inscribed circle of the cylindrical roller 13 constituting the radial roller bearing 14a, and at the same time the inner diameter d of the inner ring 16. ₁₆ can be appropriately set corresponding to the outer diameter of the support shaft 9b. As a result, the degree of freedom in designing the outer diameter of the support shaft 9b and the inner diameter of the support holes 15b and 15c of the support walls 12b and 12c can be improved.

In accordance with the improvement in the degree of freedom in design, if the support shaft 3a and the support wall portions 4a and 4b can be miniaturized, the lubricity of the radial roller bearing 14a can be improved. That is, according to the predetermined curing (小徑化) of the support shaft (3a), the support wall portion (12b, 12c), haejyeoseo is possible to reduce the dimensions (H ₁₂₎ of these height direction of the support wall portion (12b, The area of the part which overlaps with respect to the axial direction of the width direction inner side surface of 12c) and the axial direction both end surfaces of the tappet roller 8b can be reduced. For this reason, the bearing space 21 in which the lubricating oil is arrange | positioned from the outside through the part between the width direction inner surface of the support wall parts 12b and 12c, and the axial both end surfaces of the tappet roller 8b is arrange | positioned from the outside. ) Easy to enter into.

In the cam follower device of this example, miniaturization and weight reduction are also achieved by providing the inner ring 16. In other words, the support wall portions 12b and 12c are predetermined with respect to the radial direction of the support holes 15b and 15c around the support holes 15b and 15c of the support wall portions 12b and 12c in order to secure desired rigidity. It is necessary to secure the width dimension L ₁₂ . In this example, the outer diameter D ₉ of the support shaft 9b can be reduced by changing the inner diameter d ₁₆ of the inner ring 16. For this reason, these of the support wall portions 12b and 12c are secured while securing a constant width dimension with respect to the radial direction of the support holes 15b and 15c around the support holes 15b and 15c of the support wall portions 12b and 12c. The dimension H ₁₂ with respect to the height direction (up and down direction in FIG. 1) can be made small. As a result, it becomes possible to reduce the size and weight of the support wall portions 12b and 12c, and further, the entire rocker arm 1b.

In addition, in the manufacture of the cam follower device of the present example, a crimping operation is unnecessary, and accordingly a jig such as a punch for forming a crimping portion is also unnecessary. In addition, the hardening process for hardening the support shaft 9b can be performed by immersion hardening which is cheaper than the high frequency quenching process. Moreover, no stop plug is required at the time of assembly. As a result, it is possible to reduce the machining cost and the component cost, and further reduce the manufacturing cost of the entire cam follower device.

[Second example of embodiment]

2 shows a second example of embodiment of the present invention. In the case of the cam follower device of this example, relative rotation with respect to the inner ring 16a is possible on the outer circumferential surface of the inner ring 16a fitted on the outer circumferential surface of the axial middle portion of the support shaft 9b and the outer diameter side of the inner ring 16a. The inner circumferential surface of the tappet roller 8b provided by this is in sliding contact. In addition, the shape and dimensions of the tappet roller 8b are almost the same as in the first example of the embodiment.

That is, the cam follower device of the present example has a so-called double roller type structure in which the radial roller bearing 14a of the first example of the embodiment is omitted. However, similarly to the inner ring 16 of the 1st example of embodiment, the inner ring 16a which comprises the cam follower apparatus of this example is with the support shaft 9b on the outer peripheral surface of the axial middle part of the support shaft 9b. It is fitted by an interference fit in the state which can be rotated (relative rotation with respect to the support shaft 9b). Therefore, from a functional point of view, the cam follower device of this example functions as a so-called single roller type cam follower device. Other structures, actions and effects of this example are the same as in the first example of the embodiment.

[Third example of embodiment]

3 shows a third example of embodiment of the present invention. In the case of the cam follower apparatus of this example, the inner diameter side roller 20 which is a cylindrical member is made between the outer peripheral surface of the inner ring 16 fitted on the outer peripheral surface of the axial middle part of the support shaft 9b, and the inner peripheral surface of the tappet roller 8b. The relative rotation with respect to the inner ring 16 and the tappet roller 8b is provided in the state possible. In addition, the shape and dimensions of the tappet roller 8b and the inner ring 16 are almost the same as in the first example of the embodiment.

That is, the cam follower device of the present example has a so-called triple roller type structure in which the inner diameter side roller 20 is provided instead of the radial roller bearing 14a of the first example of the embodiment. However, as for the inner ring 16 which comprises the cam follower apparatus of this example, the relative rotation with respect to the support shaft 9b is prevented on the outer peripheral surface of the axial middle part of the support shaft 9b similarly to the 1st example of embodiment. It is fitted in the state (rotable with the support shaft 9b). Therefore, from a functional point of view, the cam follower device of this example functions as a so-called double roller type cam follower device. Other structures, actions and effects of this example are the same as in the first example of the embodiment.

[Fourth example of embodiment]

4 and 5 show a fourth example of embodiment of the present invention. In the case of the cam follower device of this example, a circular ring shape made of hard metal or synthetic resin is formed between the widthwise inner surfaces of the pair of support walls 12d and 12e and the axial end surfaces of the inner ring 16 with respect to the axial direction. A pair of washers 22 are provided. In addition, the outer diameter D ₂₂ of the washer 22 is larger than the inner diameter d ₈ of the tappet roller 8b (D ₂₂ > d ₈ ). That is, the washer 22 is provided in the state which closed the opening part of the axial direction both ends of the bearing space 21 in which the cylindrical roller 13 which comprises the radial roller bearing 14a is arrange | positioned. In addition, in this example, the outer diameter D ₂₂ of the washer 22 is made larger than the dimension H _12d with respect to the height direction (up-down direction in FIG. 4 and FIG. 5) of the support wall parts 12d and 12e. (D ₂₂ > H _12d ).

According to the cam follower device of the present example, compared with the structure of the first example of the embodiment, the size and weight can be further reduced. That is, in this example, the washer 22 prevents the cylindrical roller 13 from escaping from the bearing space 21 in the axial direction by closing the axial openings at both ends of the bearing space 21. For this reason, it is not necessary to aim at the fall prevention of the cylindrical roller 13 with respect to the axial direction by the support wall parts 12d and 12e. As a result, the dimension H _{12d with} respect to the height direction of the support wall parts 12d and 12e can be made small, and the size and weight of the rocker arm including the support wall parts 12d and 12e can be reduced.

In addition, in this example, the washer 22 closes the openings at both ends of the bearing space 21 in the axial direction. This prevents the widthwise inner surfaces of the support plate portions 12d and 12e from abrasion due to friction with the rollers 13 constituting the radial roller bearing 14a, thereby extending the life of the support wall portions 12d and 12e. Can be planned. Other structures, actions and effects of this example are the same as in the first example of the embodiment.

[Fifth example of the embodiment]

6 and 7 show a fifth example of embodiment of the present invention. In the case of the cam follower apparatus of this example, the dimension L _{16b with} respect to the axial direction of the inner ring 16b compared with the dimension L ₁₆ with respect to the axial direction of the inner ring ₁₆ (refer FIG. 1) of the 1st example of embodiment. ) Is increased (L _16b > L ₁₆ ). In addition, the shape and dimension of the tappet roller 8b are substantially the same as the 1st example of embodiment. Therefore, both the axial ends of the inner ring 16b are located outside the width direction than both the axial ends of the tappet roller 8b.

Moreover, in the width direction inner side rather than the width direction inner surface of the support wall parts 12d and 12e, and in the axial direction both ends (part in the width direction outer side of the axial both ends of the tappet roller 8b) of the outer peripheral surface of the inner ring 16b. A pair of circular ring washers 22a are provided. The outer diameter D _22a of the washer 22a is larger than the inner diameter d ₈ of the tappet roller 8b (D _22a > d ₈ ). Therefore, the washer 22a is provided in the state which closed the opening part of the axial direction both ends of the bearing space 21 in which the cylindrical roller 13 which comprises the radial roller bearing 14b is arrange | positioned.

Also in this example, the outer diameter D _22a of the washer 22a is the dimension H _12d of the support wall portions 12d and 12e with respect to the height direction of the support wall portions 12d and 12e (up and down directions in FIGS. 6 and 7). ) (D _22a > H _12d ). The other structures, operations and effects of this example are the same as in the fourth example of the embodiment.

[Sixth example of the embodiment]

8 and 9 show a sixth example of embodiment of the present invention. As compared with the dimension (L ₈₎ in the axial direction in this embodiment the cam follower when the device, in the first embodiment example tappet roller (8b), larger dimensions (L _8c) in the axial direction of the tappet roller (8c) (L _8c > L ₈ ). In addition, the shape and dimension of the inner ring 16 are substantially the same as the 1st example of embodiment. Therefore, both the axial ends of the tappet roller 8c are located outside the width direction than both the axial ends of the inner ring 16.

Moreover, the support wall part 12d with respect to the axial direction of the inner diameter side of the axial both ends of the tappet roller 8c (the part which is width direction outer side rather than the axial both ends of the inner ring 16), and the outer peripheral surface of the support shaft 9b. , A pair of circular ring-shaped washers 22b are provided between the widthwise inner surface of the surface 12e and the axially opposite end surfaces of the inner ring 16. In addition, the outer diameter D _22b of the washer 22b is slightly smaller than the inner diameter d ₈ of the tappet roller 8c (D _22b <d ₈ ). That is, the washer 22b is provided in the state which closed the opening part of the axial direction both ends of the bearing space 21 in which the cylindrical roller 13 which comprises the radial roller bearing 14c is arrange | positioned.

Also in this example, the outer diameter D _22b of the washer 22b is made larger than the dimension H _12d of the support wall portions 12d and 12e with respect to the height direction of the support wall portions 12d and 12e (D _22b). > H _12d ). The other structures, operations and effects of this example are the same as in the fourth example of the embodiment.

[Seventh example of the embodiment]

10 and 11 show a seventh example of embodiment of the present invention. In the case of the cam follower apparatus of this example, the radial roller bearing 14d combines the inner ring 16b (refer FIG. 6) of the 5th example of embodiment, and the tappet roller 8c (refer FIG. 8) of the 6th example of embodiment. It consists of: That is, in this example case, the embodiment of the first example tappet roller (8b) (see FIG. 1) as compared with the dimension (L ₈₎ in the axial direction, the tappet roller (8c) the axial dimension (L _8c in the direction of the ) Is increased (L _8c > L ₈ ) and at the same time, compared to the dimension L ₁₆ with respect to the axial direction of the inner ring ₁₆ (see FIG. 1) of the first example of the embodiment, in the axial direction of the inner ring 16b. The size L _16b is increased (L _16b > L ₁₆ ). In addition, the dimension with respect to the axial direction of a tappet roller and an inner ring is made the same as the 1st example of embodiment, and the dimension with respect to the axial direction of a cylindrical roller is the cylindrical roller 13 of a 1st example of this embodiment (refer FIG. 1). It can also be made smaller.

Moreover, a pair of circular ring washer 22c is provided between the axial both ends of the outer peripheral surface of the inner ring 16b, and the axial both ends of the inner peripheral surface of the tappet roller 8c. That is, the washer 22c is provided in the state which closed the opening part of the axial direction both ends of the bearing space 21 in which the cylindrical roller 13 which comprises the radial roller bearing 14d is arrange | positioned. In addition, in the case of this example, it is also possible to use a holding machine instead of the washer 22c.

Also in this example, the outer diameter D _22c of the washer 22c is the dimension H of the support wall portions 12d and 12e with respect to the height direction of the support wall portions 12d and 12e (up and down directions in FIGS. 10 and 11). ₁₂ d) (D _22c > H _12d ). The other structures, operations and effects of this example are the same as in the fourth example of the embodiment.

1, 1a, 1b: rocker arm 2: shaft hole
3: rocker shaft 4: adjustment bolt
5: lock nut 6: engine valve
7: return spring 8, 8a, 8b: tappet roller
9, 9a, 9b, 9c: support shaft 10: cam
11: camshaft
12, 12a, 12b, 12c, 12d, 12e: support wall
13: cylindrical roller
Radial Roller Bearings: 14, 14a, 14b, 14c, 14d
15, 15a, 15b, 15c, 15d, 15e: support hole
16, 16a, 16b: inner ring 17: inner ring track
18: outer ring raceway 19: roller assembly
20: inner diameter side roller 21: bearing space
22, 22a, 22b, 22c: washers

Claims (7)

It has a pair of support wall portions provided at intervals from each other, and a pair of support holes formed at positions where these support wall portions are matched with each other, and provided opposite to a cam fixed to a cam shaft rotating in synchronism with the crankshaft of the engine. A rocker arm that swings and displaces in response to the movement of this cam,
A support shaft supported on these support wall portions by crossing between the pair of support wall portions in a state where both ends thereof are inserted through the pair of support holes;
An inner ring equivalent member having an outer diameter larger than the inner diameter of the support hole, and fitted on the axial middle portion of the support shaft in a state in which relative rotation with respect to the support shaft is prevented and fitted by an interference fit;
It is provided with the tappet roller arrange | positioned around the said inner ring equivalent member so that relative rotation with respect to this inner ring equivalent member is possible.
Cam follower device. The method of claim 1,
Both ends of the support shaft are fitted in the pair of support holes by a gap fitting to enable rotation inside the support holes.
Cam follower device. The method of claim 1,
A radial roller bearing is provided between the inner circumferential surface of the tappet roller and the outer circumferential surface of the inner ring equivalent member.
Cam follower device. The method of claim 3, wherein
The radial roller bearing is constituted by a total roller bearing
Cam follower device. 5. The method of claim 4,
A pair of circular shapes having an outer diameter larger than the dimension of the support wall portion in the height direction of the support wall portion in a state in which the openings at both ends of the bearing space of the radial roller bearing are closed in the widthwise inner side of the pair of support wall portions. Ring washers
Cam follower device. The method of claim 1,
The inner circumferential surface of the tappet roller and the outer circumferential surface of the inner ring equivalent member are in sliding contact with each other.
Cam follower device. The method of claim 1,
Between the inner peripheral surface of the said tappet roller and the outer peripheral surface of the said inner ring equivalent member, a cylindrical member is arrange | positioned so that relative rotation with respect to this tappet roller and an inner ring equivalent member is possible.
Cam follower device.

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