JP2008185170A - One-way clutch - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a one-way clutch with a retainer having large torque capacity in a level near a full type roller system, and capable of facilitating installation and attachment. <P>SOLUTION: The number of rollers 2 is increased by abutting a plurality of the rollers 2 with each other so as to be assembled, a protrusion 8 for preventing coming off of the rollers 2 is provided on both annular side parts 5 of the retainer 3 so as to facilitate installation and attachment, a pillar 6 of the retainer 3 is press-fitted in an inner periphery of an outer ring 1, the both annular side parts 5 are slidably brought into contact with a cylindrical surface of an outer periphery of a shaft A, and the radial load applied to the shaft A is received by the retainer 3. Thus, the radial bearing conventionally assembled in both sides of the retainer is dispensed with, the roller 2 is increased by that, and the torque capacity is increased to the level near the full type roller system. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a one-way clutch using rollers as engaging elements.

  A one-way clutch using a roller as an engagement element includes an annular member (outer ring or inner ring) provided with a plurality of inclined cam surfaces on the inner periphery or outer periphery, and a plurality of rollers disposed at positions facing the respective cam surfaces. And a cage for accommodating the rollers one by one in a pocket formed by a pair of annular side portions and a plurality of column portions connecting the annular side portions, and pressing each roller in a direction to engage the cam surface. In many cases, the elastic member is attached to an inner member or an outer member having a cylindrical surface opposite to the cam surface with the roller interposed therebetween.

On the other hand, if the cage is eliminated and the rollers are placed in contact with each other (in the total roller state), the number of rollers is increased without changing the size of the entire clutch, and the torque capacity is increased. (For example, refer to Patent Documents 1 and 2.) However, such a one-way clutch with a full roller system does not have a retainer, so a separate means is required to prevent the rollers from dropping off during transportation or when mounted on the shaft. The inner ring has an inner ring with torque transmission means, or a dummy inner ring with the same outer diameter as the shaft is fitted during assembly (in the case of the inner ring cam type, is it a specification with an outer ring? Fit the dummy outer ring). For this reason, there is a problem that it takes time and labor when assembling and mounting, compared to a type having a cage.
JP 2001-304299 A JP 2003-56601 A

  Therefore, the present applicant has been working on the development of a one-way clutch having a large torque capacity and being easy to assemble and mount. Of the one-way clutches developed so far, an example of an outer ring cam type is shown in FIGS. In this clutch, a plurality of rollers 52 disposed at positions facing the inclined cam surface 51a on the inner periphery of the outer ring 51 are brought into contact with each other in a pocket between the column portions 54 of the cage 53, and a spring (elastic body) ) 55 is pressed in a direction to engage with the cam surface 51a, and the two annular side portions 56 of the retainer 53 are protruded into the pocket 54 to restrict the movement of each roller 52 in the direction away from the cam surface 51a. Is provided on the outer periphery of the shaft A having a cylindrical surface facing the cam surface 51a across the roller 52 (see Japanese Patent Application No. 2006-252889).

  The one-way clutch shown in FIGS. 9 and 10 can increase the torque capacity by increasing the number of rollers as compared with the conventional type in which the rollers are accommodated one by one in the pocket of the cage, and is being conveyed. In addition, there is no risk of the rollers falling off during installation, and no inner ring or dummy inner ring is required. Therefore, assembly and installation can be performed more easily than the full-roller type. However, normally, as shown in FIG. 10, bearings 58 that receive the radial load applied to the shaft A and also prevent the retainer 53 from coming off in the axial direction are incorporated on both sides of the retainer 53. Compared to the roller type, the length of the roller 52 is shorter by the amount of the installation space of the two bearings 58, and there is a considerable difference in terms of torque capacity.

  An object of the present invention is to provide a one-way clutch with a cage that has a large torque capacity at a level close to that of a full-roller system and is easy to assemble and mount.

  In order to solve the above problems, the present invention provides an annular member provided with a plurality of inclined cam surfaces on the inner periphery or outer periphery, a plurality of rollers disposed at positions facing each of the cam surfaces, and a pair of annular members. A cage for accommodating a plurality of the rollers in contact with each other in a pocket formed by a side portion and a plurality of pillars connecting the annular side portions, and engaging the rollers with the cam surface A one-way clutch provided with an elastic body that presses in a direction to move, and provided on both annular side portions of the cage with protrusions that protrude into the pocket and restrict movement of the rollers in a direction away from the cam surface. The retainer is press-fitted and fixed to the annular member, and the annular side portion of the retainer is brought into sliding contact with the inner member facing the cam surface of the annular member or the cylindrical surface of the outer member across the roller. Adopted the configuration.

  That is, increase the number of rollers by placing a plurality of rollers in contact with each other in the cage pocket and increasing the number of rollers, and providing protrusions on both annular sides of the cage to prevent the rollers from falling off. Can be easily performed, and the retainer is press-fitted and fixed to the annular member, and the retainer retains the radial load applied to the inner member or the outer member. This eliminates the need for the radial bearings incorporated on both sides of the cage, and lengthens the rollers to increase the torque capacity to a level close to that of the full roller system.

  Further, as the elastic body that presses each roller, a spring member in which two coil springs arranged in parallel and a connecting portion for connecting one end thereof are formed by a single wire is adopted, and the column portion of the cage Further, if a recess for accommodating the connecting portion of the spring member in a bent state is provided, the spring member can be easily attached to the cage without fear of dropping off, and the assembly of the entire clutch can be improved. .

  As described above, the one-way clutch of the present invention increases the number of rollers so as to accommodate a plurality of rollers in contact with each other in the pocket of the cage, and is incorporated on both sides of the conventional cage. Since the radial bearing is not required and the rollers can be made longer than before, the torque capacity can be increased to a level close to that of the full roller system. In addition, since the rollers are provided with protrusions for preventing the rollers from dropping, assembly and mounting can be performed more easily than those using the full roller system.

  Hereinafter, embodiments of the present invention will be described with reference to FIGS. 1 to 8. As shown in FIGS. 1 to 3, the one-way clutch is an outer ring cam type in which a plurality of inclined cam surfaces 1a are provided on the inner periphery of the outer ring (annular member) 1, and is located at a position facing each cam surface 1a. A roller 2 is disposed and is mounted on the outer periphery of the shaft A having a cylindrical surface facing the cam surface 1a across the roller 2. The rollers 2 are held by the retainer 3 in a state where a plurality of rollers 2 are in contact with each other, and are pressed in a direction to engage with the cam surface 1 a by a spring member (elastic body) 4 attached to the retainer 3. ing. Further, on the outer periphery of the outer ring 1, a ridge 1b as torque transmitting means is formed over the entire periphery.

  1 and 2, when the outer ring 1 rotates clockwise or the shaft A rotates counterclockwise, each roller 2 engages with the cam surface 1a and torque is transmitted. On the other hand, when the outer ring 1 rotates counterclockwise or the axis A rotates clockwise, the engagement between the rollers 2 and the cam surface 1a is released, and the outer ring 1 or the axis A rotates idle.

  As shown in FIG. 4, the retainer 3 includes a pair of annular side portions 5 and a plurality of column portions 6 that connect both the annular side portions 5, and is formed by the both annular side portions 5 and the column portions 6. A plurality of rollers 2 are accommodated in the plurality of pockets 7. Further, projections 8 having a substantially triangular cross section projecting into the pocket 7 are provided at the inner peripheral edge portions of both annular side portions 5 in accordance with the roller pitch, and the direction in which these projections 8 are separated from the cam surface 1a of the roller 2 is provided. The movement of the roller 2 is restricted so that the roller 2 is not dropped from the inner peripheral side. Then, when each column portion 6 is press-fitted into a position without the cam surface 1a on the inner periphery of the outer ring 1, both annular side portions 5 formed to have an inner diameter substantially the same as the outer diameter of the shaft A become the outer peripheral cylinder of the shaft A. The structure is configured to receive a radial load applied to the shaft A in sliding contact with the surface.

  As shown in FIG. 5, the spring member 4 is formed by forming two coil springs 4 a arranged in parallel and a connecting portion 4 b for connecting one end thereof with a single wire. In order to attach the spring member 4 to the cage 3, a recess 6 a is formed in the column portion 6 of the cage 3.

  As shown in FIG. 6, the recess 6 a of the cage column 6 has a shape in which one end of the spring member 4 is fitted from the inner peripheral side of the cage 3, and the coupling portion 4 b of the spring member 4 is fitted. A protruding portion 6b that bends the connecting portion 4b is formed on one side surface of the groove. Thereby, the spring member 4 can be easily attached to the cage 3 without fear of dropping off. In addition, as shown in FIG. 7, the shape of the recessed part 6a is accommodated in a state where a plurality of concavities and convexities facing each other are formed on both side surfaces of the groove into which the connecting part 4b of the spring member 4 is fitted, and the connecting part 4b is bent. It can also be done.

  This one-way clutch is configured as described above, and a plurality of rollers 2 are brought into contact with each other in the pocket 7 of the cage 3 so that the rollers are accommodated one by one in the pocket of the cage. There are many numbers of rollers. Further, since the cage 3 is press-fitted and fixed to the outer ring 1 to receive a radial load applied to the shaft A, a radial bearing that also serves as a retainer for retaining the cage is incorporated on both sides of the cage as in the prior art. There is no need, and the roller 2 can be made longer than before. As a result, the torque capacity is at a level close to that of a full-roller clutch.

  In addition, since the retainer 3 is provided with a protrusion 8 that prevents the roller 2 from falling off, there is no need to fit or remove the retainer and another drop-off prevention means as in the case of the full roller type. Attaching to A can be performed easily. Further, as the elastic body that presses the roller 2, a spring member 4 in which two coil springs 4a are connected is adopted so that the spring member 4 can be easily attached to the retainer 3 without fear of dropping off. This makes the entire clutch easy to assemble.

  FIG. 8 shows a modification of the press-fitting structure of the cage 3 to the outer ring 1. In this modification, the cam surface 1 a of the outer ring 1 is formed over the entire width of the outer ring 1, and irregularities along the shape of the cam surface 1 a of the outer ring 1 are provided on the outer periphery of both annular side portions 5 of the cage 3. Both annular side portions 5 are press-fitted into the inner periphery of the outer ring 1. If it does in this way, it will become easy to process the internal peripheral surface of the outer ring | wheel 1, and the reduction of manufacturing cost can be aimed at.

  The present invention is not limited to the outer ring cam type of the embodiment described above, but is also an inner ring cam type that is mounted on an outer member having a cam surface on the outer periphery of the inner ring (annular member) and a cylindrical surface on the inner periphery. Of course, it can also be applied to one-way clutches.

Longitudinal front view showing a mounted state of the one-way clutch of the embodiment 1 is an enlarged front view of the main part of FIG. Sectional view along line III-III in FIG. External perspective view of the cage of FIG. 1 is an external perspective view of the spring member of FIG. The principal part expansion perspective view of the holder | retainer of FIG. The principal part expansion perspective view which shows the modification of the recessed part shape of a holder | retainer pillar part Side view showing a modification of the press-fitting structure to the outer ring of the cage Main part enlarged longitudinal front view showing a conventional one-way clutch mounted state Sectional view along line XX in FIG.

Explanation of symbols

1 Outer ring (annular member)
1a cam surface 1b protrusion 2 roller 3 cage 4 spring member (elastic body)
4a Coil spring 4b Connection part 5 Annular side part 6 Column part 6a Recess 6b Projection part 7 Pocket 8 Projection A Axis

Claims (2)

  An annular member provided with a plurality of inclined cam surfaces on the inner periphery or outer periphery, a plurality of rollers disposed at positions facing the respective cam surfaces, a plurality of annular side portions, and a plurality connecting these annular side portions A cage that holds a plurality of the rollers in contact with each other in a pocket formed by the pillar portion, and an elastic body that presses the rollers in a direction to engage the cam surface, In a one-way clutch provided on both annular side portions of the cage with protrusions that project into the pocket and restrict the movement of the rollers in a direction away from the cam surface, the cage is press-fitted and fixed to the annular member. The one-way clutch characterized in that the annular side portion of the cage is brought into sliding contact with an inner member or an outer member cylindrical surface facing the cam surface of the annular member with the roller interposed therebetween.   The elastic body that presses each roller is a spring member formed by connecting one end of two coil springs arranged in parallel and one end thereof with a single wire, and the column of the cage The one-way clutch according to claim 1, further comprising a recess that accommodates the connecting portion of the spring member in a bent state.

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