JPH11270639A - Loading cam device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the efficiency of a loading cam device by forming a cam roller for receiving a disk axial load and the adjacent cam roller or an abutment part to be brought into contact with a holder of separate parts. SOLUTION: A loading cam roller device is formed of a cam roller 17 for receiving an axial load to be generated by riding over a cam surface, and a spherical abutment part 19 for abutting on an adjacent cam roller 17 or a holder, and low friction processing such as teflon working is performed to a surface of the abutment part 19. Since the abutment part 19 is formed into the spherical shape, even in the case where the rotating directions of the adjacent cam rollers cross each other, contact at the abutment part 19 is always formed into the point contact, and condition of a low friction part is stabilized, and durability is secured, and while friction due to the centrifugal force of the cam roller 17 is hard to be generated. Efficiency of the loading cam device is thereby improved.

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a technology for improving the efficiency of a loading cam device. 2. Description of the Related Art As a conventional loading cam device of this type, for example, one disclosed in Japanese Patent Application Laid-Open No. 1-299358 is known. This conventional loading cam device is used, for example, in a toroidal-type continuously variable transmission, and as shown in FIG. 6, an input disk 1, an output disk 2, and a toroidal transmission formed by both disks 1 and 2. A pair of power rollers 3, 3 arranged in frictional contact with both disks 1, 2 in a groove of a shape, and a pair of trunnions for rotatably supporting the power rollers 3, 3 via pivot shafts, respectively. , And each of the disks 1 and 4 for transmitting power according to the input torque.
A loading cam 5 for generating a force in the disk axial direction is arranged between the power rollers 2 and the power rollers 3. Then, a ring-shaped cam roller holding member 6
Four openings are formed at equal intervals in the circumferential direction, and three cam rollers 7, 7, 7 are respectively fitted and held in each opening so as to be rotatable about a radial axis of the torque input shaft 9. It is configured. In addition, a contact portion 8 that is significantly smaller than the area of the cam roller end is formed on the side surface of the cam rollers 7, 7, 7 in the outer diameter direction of the cam roller holding member. [0005] However, even in the conventional loading cam device configured as described above, in order to further improve the effect, the contact portion is subjected to surface treatment or the like to reduce friction. However, since the end surface of the cam roller is smaller than the outer diameter of the cam roller, it is easy for the adjacent rollers to intersect with each other in rotation direction. In addition, there is a problem that the effect of the formation of the low frictional portion is hardly obtained, and the durability of the low frictional portion is impaired by applying a high surface pressure to the low frictional portion. SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a conventional cam roller in which a cam roller which bears an axial load and a cam roller or a holder adjacent to the cam roller are brought into contact. It is an object of the present invention to provide a loading cam device capable of improving efficiency by separately forming a contact portion to be subjected to a low friction treatment on the contact portion. In order to achieve the above object, according to the present invention, there is provided a first member which is rotatable integrally with a torque input shaft and is attached while being locked in an axial direction. And a second member mounted rotatably relative to the torque input shaft and movably in the axial direction, and a cam surface formed on each of the opposing surfaces of the first and second members. One or a plurality of stacked cam rollers, and a cam roller holding member formed with an opening for fitting and holding the cam rollers so as to be relatively rotatable about a radial axis of the torque input shaft. The technical premise of the present invention is a loading cam device in which the cam roller rolls between cam surfaces according to a torque difference between the first member and the second member, and the axial pressing force of the second member changes. , Disk axial load The cam roller which bears the weight and the contact portion which comes into contact with the cam roller or the holder adjacent to the cam roller are formed as separate parts. According to the present invention, the contact portion is formed by performing a low friction treatment such as Teflon processing. Further, in the present invention, the contact portion is formed by a sphere, a cylinder and a hemisphere or a sphere, or a cylinder and a truncated cone or a cone. It is desirable to form. Further, in the present invention, it is desirable that the cam roller and the contact portion are connected via an elastic body at the rotation center of the cam roller. In this case, it is desirable to hold one end of the elastic body at a position near the axis of the retainer. An embodiment of the present invention will be described below in detail with reference to the accompanying drawings. FIG. 1 shows a cam roller portion of a loading cam device provided in a loading cam device according to a first embodiment of the present invention. The loading cam device rides on a cam surface thereof. It comprises a cam roller 17 which bears the generated axial load, and a spherical contact portion 19 which comes into contact with the adjacent cam roller 17 or the retainer 18 (see FIG. 5). The surface of the contact portion 19 is made of Teflon. Low friction treatment such as processing is applied.
The other configuration and operation of the loading cam device according to the present embodiment are the same as those of the loading cam device described in the related art, and thus the detailed description thereof is omitted here. Therefore, in the loading cam device according to this embodiment, since the shape of the contact portion 19 is spherical, even if the rotation directions of the adjacent cam rollers 17 intersect, the contact of the contact portion 19 can be prevented. Is always in point contact, and the condition for the low friction portion is stabilized, so that an effect is obtained that friction is hardly generated due to the centrifugal force of the cam roller 17 while durability is secured. FIG. 2 shows a cam roller portion of a loading cam device provided in a loading cam device according to a second embodiment of the present invention. In this embodiment, the shape of the contact portion 19 is Column 20 and hemisphere or sphere 21
And the area of the cam roller 17 which bears the centrifugal force becomes larger than the contact portion 19 of the first embodiment, so that the surface pressure can be reduced. The durability can be improved more than the contact portion 19 of the first embodiment. FIG. 3 shows a cam roller portion of a loading cam device provided in a loading cam device according to a third embodiment of the present invention. In this embodiment, the shape of the contact portion 19 is Cylinder 20 and cone or truncated cone 2
2 is formed in a shape in which they are combined with each other, so that an effect similar to that of the second embodiment can be obtained, and an effect that processing of the contact portion 19 is simpler than that of the second embodiment can be obtained. FIG. 4 shows a cam roller portion of a loading cam device provided in a loading cam device according to a fourth embodiment of the present invention. Since the respective cam rollers 17 are connected by inserting the elastic body 24 into the through hole 23, the complexity of assembly due to an increase in the number of parts in the first to third embodiments is improved, and the assembly is simplified. Can be planned. However, in this case, the elastic body 24 is disposed so that the elastic body 24 does not exist on the contact surface at the contact portion 19 that comes into contact with the retainer 18. FIG. 5 shows a cam roller portion of a loading cam device provided in a loading cam device according to a fifth embodiment of the present invention. In this embodiment, the elastic member according to the fourth embodiment is shown. 24, one end near the axis center,
By coupling with the retainer 18, the frictional force between the cam roller 17 and the retainer 18 can be further reduced, and the durability of the low friction processing can be further improved. In the above description, the present invention is applied to a toroidal type continuously variable transmission. However, in addition to the above, a mechanism that expects an action corresponding to the torque, for example, LS
Of course, it can be used for D or a forward / reverse switching mechanism of an automatic transmission, or a switching mechanism of 2WD and 4W. As described above, in the loading cam device according to the present invention, the cam roller bearing the load in the axial direction is formed separately from the cam roller adjacent to the cam roller or the contact portion which comes into contact with the retainer. In addition to the formation, the contact portion is subjected to a low friction treatment, so that the effect of the frictional force generated by the centrifugal force of the cam roller is reduced, and the excellent effect that the efficiency of the loading cam device can be easily improved is obtained. can get. Further, according to the present invention, since the friction between the adjacent cam rollers or the retainer can be reduced, the cam rollers can be easily rotated, and the contact friction condition between the cam rollers and the cam surface can be improved. Can also be obtained.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic explanatory view showing a cam roller portion of a loading cam device provided in a toroidal type continuously variable transmission according to a first embodiment of the present invention. FIG. 2 is a schematic explanatory view showing a cam roller portion of a loading cam device provided in a toroidal type continuously variable transmission according to a second embodiment of the present invention. FIG. 3 is a schematic explanatory view showing a cam roller portion of a loading cam device provided in a toroidal type continuously variable transmission according to a third embodiment of the present invention. FIG. 4 is a schematic explanatory view showing a cam roller portion of a loading cam device provided in a toroidal type continuously variable transmission according to a fourth embodiment of the present invention. FIG. 5 is a schematic explanatory view showing a cam roller portion of a loading cam device provided in a toroidal type continuously variable transmission according to a fifth embodiment of the present invention. FIG. 6 is a sectional view showing an input shaft portion of the toroidal type continuously variable transmission. FIG. 7 is a schematic explanatory view showing a cam roller portion of a loading cam device provided in a conventional toroidal type continuously variable transmission. DESCRIPTION OF SYMBOLS 1 Input disk 2 Output disk 3 Power roller 5 Loading cam device 17 Cam roller 18 Cage 19 Contact part 20 Column part 21 Spherical part 22 Frustoconical part 24 Elastic body

Claims (1)

Claims: 1. A first member rotatably and integrally rotatable with a torque input shaft, and a first member locked and mounted in an axial direction, rotatably relative to the torque input shaft, and , A second member mounted movably in the axial direction, and the first and second members.
One or a plurality of cam rollers arranged in contact with cam surfaces formed respectively on opposing surfaces of the member, and the cam rollers are fitted so as to be relatively rotatable about a radial axis of the torque input shaft. A cam roller holding member having an opening for holding the cam member, wherein the cam roller rolls between cam surfaces according to a torque difference between the first member and the second member, and a shaft of the second member is provided. A cam roller that bears a load in the disk axial direction and a contact portion that contacts a cam roller or a holder adjacent to the cam roller, which are formed as separate parts. . 2. The loading cam device according to claim 1, wherein the contact portion is subjected to low friction processing such as Teflon processing. 3. The loading cam device according to claim 1, wherein the contact portion is formed of a sphere. 4. The loading cam device according to claim 1, wherein the contact portion is formed by combining a cylinder and a hemisphere or a spherical surface. 5. The loading cam device according to claim 1, wherein the contact portion is formed by combining a cylinder and a truncated cone or a cone. 6. The loading cam device according to claim 1, wherein the cam roller and the contact portion are connected via an elastic body at a rotation center of the cam roller. 7. The loading cam device according to claim 5, wherein one end of an elastic body that couples the cam roller and the contact portion at a rotation center of the cam roller is held at a position near an axis of a retainer.