Roller and cam clutch unit

Abstract

The objective is to provide a roller for a cam clutch unit that can reduce contact with the spring, and a cam clutch unit using the same that can suppress the generation of drag torque. [Solution] The rollers 20, 30, and 40 are used in a cam clutch unit 10 which comprises at least a plurality of cams 11 arranged between an inner ring and an outer ring that are coaxially rotatable relative to each other, and an annular spring 12 that biases the cams 11. The rollers 20, 30, and 40 are arranged together with the cams 11 between the inner ring and the outer ring, and each roller 20, 30, and 40 consists of a pair of roller portions 21, 31, and 41 and pin portions 22, 32, and 42 provided between the roller portions 21, 31, and 41, and is characterized in that at least one of the roller portions 21, 31, and 41 and the pin portions 22, 32, and 42 are separate.

Description

Technical Field

[0001] The present invention relates to a roller and a cam clutch unit.

Background Art

[0002] As a cam clutch unit for transmitting and blocking torque between an input shaft and an output shaft, there is one provided with a plurality of cams and a plurality of rollers arranged in the circumferential direction between an inner ring and an outer ring that are relatively rotatable coaxially, and an annular spring for biasing the cams. Further, there is also one provided with a cage ring having a plurality of pocket portions for restricting the relative movement in the circumferential direction of the cams and the rollers.

[0003] For example, in the case of a cam clutch unit provided with a cage ring described in Patent Document 1, a plurality of cams and a plurality of rollers are accommodated in the pocket portions of the cage ring, and the relative movement in the circumferential direction of the cams and the rollers is restricted.

[0004] In this case, as shown in FIG. 8, the roller has a groove portion 102 formed in the circumferential direction between a pair of roller portions 101 that function as the roller 100, and a spring 103 is accommodated in the groove portion 102 so as to bias the roller 100 toward the inner ring side.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] In a cam clutch unit using such a roller 100, the groove 102 of the roller 100 is not deep enough relative to the roller surface of the roller 101, which could cause it to come into contact with the spring 103, potentially generating drag torque (frictional sliding) between the spring 103 and the roller 103. Furthermore, the deterioration of the spring 103 due to wear against the roller 100 could affect the lifespan of the cam clutch itself. Additionally, because the groove 102 is located higher than the spring contact point of the cam, there was a risk that the cam adjacent to the roller 100 could not be effectively pressurized by the spring 103.

[0007] On the other hand, since the grooves 102 of the roller 100 are formed by cutting or rolling, there are limitations on the depth of the grooves that can be formed, and it was not possible to set the groove depth to one that would reduce contact with the spring 103.

[0008] Therefore, the present invention has been made in view of the above problems, and aims to provide a roller for a cam clutch unit that can reduce contact with a spring, and a cam clutch unit using the same that can suppress the generation of drag torque. [Means for solving the problem]

[0009] The present invention relates to a roller used in a cam clutch unit which comprises at least a plurality of cams arranged between an inner ring and an outer ring that are coaxially rotatable relative to each other, and an annular spring that biases the cams, wherein the roller is arranged together with the cams between the inner ring and the outer ring, and the roller consists of a pair of roller portions and a pin portion provided between the roller portions, wherein at least one of the roller portions and the pin portion are separate.

[0010] The roller of the present invention consists of a pair of roller sections and a pin section provided between the roller sections. Since at least one of the roller sections and the pin section are separate, the diameter of the pin section can be arbitrarily set. This allows the depth of the groove section formed by the opposing end faces of the roller sections and the surface of the pin section from the roller surface to be set to a desired depth, thereby reducing contact with the spring.

[0011] The roller portion, which is separate from the pin portion, is preferably provided with a through hole that penetrates its end face, and the pin portion is inserted into this through hole. By inserting the pin portion into the through hole, the roller can be constructed by assembling simple parts.

[0012] Preferably, the roller portion, which is separate from the pin portion, has a recess formed on one end face, into which the pin portion is inserted. By inserting the pin portion into the recess, the roller can be constructed by assembling simple parts.

[0013] Preferably, the pin portion is inserted so as to penetrate the through hole and protrude outward from the outer end face of the roller. With this configuration, the end of the pin portion that protrudes outward from the end face of the roller, rather than the end face of the roller, comes into contact with the cage ring or the like. As a result, the contact area is reduced, and frictional sliding between the roller and the housing can be reduced.

[0014] It is preferable that the pin portion is provided with the roller portion by a gap fit. When configured by a gap fit, the pin portion can function as a retaining pin in the outer direction of the roller, which is preferable.

[0015] It is preferable that each of the roller portions and pin portions be separate from each other. Having them separate has the advantage of reducing the amount of machining required, making it easier to construct the rollers.

[0016] The cam clutch unit of the present invention is characterized by including a plurality of cams arranged between an inner ring and an outer ring that are provided coaxially and rotatable relative to each other, the roller described in any of the above, and an annular spring that biases the cam. Since the roller described in any of the above can reduce contact with the spring, it is possible to suppress the occurrence of drag torque between the roller and the spring.

Advantages of the Invention

[0017] According to the present invention, it is possible to provide a roller for a cam clutch unit capable of setting a desired groove depth and a cam clutch unit using the same.

Brief Description of the Drawings

[0018] [Figure 1] Perspective view showing a cam clutch unit according to Embodiment 1 of the present invention. [Figure 2] Perspective view showing a roller according to Embodiment 1 of the present invention. [Figure 3] Front view showing a roller according to Embodiment 1 of the present invention. [Figure 4] Exploded perspective view showing a roller according to Embodiment 1 of the present invention. [Figure 5] Perspective view showing a roller according to Embodiment 2 of the present invention. [Figure 6] Cross-sectional view showing a roller according to Embodiment 2 of the present invention. [Figure 7] Schematic front view showing a roller according to Embodiment 3 of the present invention. [Figure 8] Front view showing a conventional roller.

Modes for Carrying Out the Invention

[0019] (Embodiment 1) Figure 1 shows a cam clutch unit 10 according to the present invention. The cam clutch unit 10 includes a plurality of cams 11 and a plurality of rollers 20 disposed between an inner ring and an outer ring (not shown) that are coaxially and circumferentially arranged, an annular spring 12 that biases the cams 11, and a cage ring 14 having pocket portions 13 that respectively accommodate the cams 11 and the rollers 20. The plurality of cams 11 and the plurality of rollers 20 are accommodated in the pocket portions 13 of the cage ring 14, so that relative circumferential movement is restricted.

[0020] The roller 20 will be described with reference to FIGS. 2 to 4. The roller 20 of the present embodiment includes a pair of roller portions 21 that function as rollers and a pin portion 22 provided across the roller portions 21. The roller portion 21 is cylindrical and includes two end faces 210 and a roller surface 212. Through holes 211 penetrating the centers of both end faces 210 on both sides are provided in the roller portions 21, respectively. The opening shape of the through hole 211 is circular, and a pin portion 22 having a solid cylindrical shape is inserted into the through hole 211. In the present embodiment, both ends of the pin portion 22 are inserted and fixed in the through hole 211 by press fitting, and the end portion 221 of the pin portion 22 is exposed from the opening of the through hole 211. In the present embodiment, the end portion 221 of the pin portion 22 is configured to be flush with the end face 210 of the roller portion 21 in the inserted and fixed state. <好

[0021] In the present embodiment, since the roller portion 21 and the pin portion 22 are provided as separate bodies and are assembled by press fitting, it is not necessary to form the pin portion 22 by cutting or the like, and the diameter of the pin portion 22 can be arbitrarily determined. Therefore, the depth H of the groove portion 23 formed by the opposing end faces 210 of the roller portion 21 and the surface of the pin portion 22 with respect to the roller surface 212 can also be arbitrarily determined, and as a result, the depth H of the groove portion 23 can be made deeper than that of the conventional one. For example, in a conventional roller formed by cutting as shown in FIG. 8, the ratio of the diameter of the pin portion to the diameter of the end face of the roller portion was greater than 40%, but in the present embodiment, for example, the ratio of the diameter of the pin portion 22 to the diameter of the end face 210 of the roller portion 21 can be set to 40% or less.

[0022] This suppresses contact between the roller portion 21 and the spring 12, thereby reducing frictional sliding between the roller portion 21 and the spring 12. Moreover, because it is an assembly of simple parts consisting of a roller and a pin, manufacturing costs can be reduced. Furthermore, by suppressing contact between the pin portion 22 and the spring 12, the set load of the spring 12 can be reduced. In addition, since the pressure applied from the spring 12 to the roller 20 is reduced, the cam 11 can be effectively pressurized, and deterioration of the spring 12 due to wear can be suppressed, thereby extending the lifespan of the cam clutch unit 10 itself.

[0023] In this embodiment, the pin portion 22 is inserted and fixed into the roller portion 21 by press-fitting, but it is not limited to this, and a clearance fit may also be used. In the case of a clearance fit, the pin portion 22 can be used to prevent the roller portion 21 from coming out in the outer diameter direction, and even in this case, contact with the spring 12 can be suppressed, which is preferable. Furthermore, although a cam clutch unit 10 equipped with a cage ring 14 is illustrated in this embodiment, it is not limited to this, and the roller 20 of this embodiment can also be preferably applied to a cam clutch unit without a cage ring 14.

[0024] (Embodiment 2) The roller 30 according to this embodiment will be described with reference to Figures 5 and 6. Note that the same aspects as other embodiments will be omitted from the explanation, and the same components will be used for explanation as necessary.

[0025] The roller 30 of this embodiment consists of a pair of roller portions 31 that function as rollers and a pin portion 32 provided between the roller portions 31. Each roller portion 31 has a recess 311 in the center of its opposing end face 310. The opening shape of the recess 311 is circular. No recess 311 is formed on the end faces 312 located at both ends of the roller 30, i.e., the non-opposing end faces 312. In other words, in this embodiment, the pin portion 32 is inserted and fixed into the recess 311 by press fitting, and the end 321 of the pin portion 32 is in close contact with the bottom surface of the recess 311 of the roller portion 31 while inserted and fixed.

[0026] In this embodiment as well, the depth H of the groove 33 can be arbitrarily determined by the diameter of the pin portion 32, similar to Embodiment 1. Therefore, by increasing the depth H of the groove 33 of the roller 30, contact between the roller 30 and the spring 12 can be suppressed, and frictional sliding between the roller 30 and the spring 12 can be reduced.

[0027] In this embodiment as well, the pin portion 32 is inserted and fixed into the roller portion 31 by press-fitting, but it is not limited to this, and may be fitted with a gap. In the case of Embodiment 1, if the pin portion 22 is fitted with a gap in the roller portion 21, it is conceivable that the roller portion 21 will move towards the center and come into contact with the spring 12, but in this embodiment, if the pin portion 32 is fitted into the recess 311, it is possible to suppress such contact even with a gap fit. Furthermore, although this embodiment illustrates a cam clutch unit 10 equipped with a cage ring 14, it is not limited to this, and the roller 30 of this embodiment can be preferably applied to a cam clutch unit that does not have a cage ring 14. (Embodiment 3)

[0028] The roller 40 according to this embodiment will be described with reference to Figure 7. Note that the same aspects as other embodiments will be omitted from the explanation, and the same components will be used for explanation as necessary.

[0029] The roller 40 of this embodiment consists of a pair of roller portions 41 that function as rollers and a pin portion 42 provided between the roller portions 41. Each roller portion 41 is provided with a through hole 411 that penetrates the center of both end faces 410. The opening shape of the through hole 411 is circular, and the ends of the solid cylindrical pin portions 22 are inserted and fixed into the through hole 411 by press fitting. In this embodiment, the ends of the pin portions 42 are inserted and provided so as to protrude outward from the end faces 410 of the roller portions 41 while they are inserted and fixed.

[0030] In this embodiment as well, the diameter of the pin portion 42 can be set to a desired value, similar to Embodiment 1. This allows the depth H of the groove portion 43 of the roller 40 to be increased, thereby suppressing contact between the roller portion 41 and the spring 12 and reducing frictional sliding between the roller portion 41 and the spring 12. In Embodiment 1, the end face 210 of the roller portion 21 contacts the cage ring 14, but in this embodiment, the pin portion 42 protruding outward from the roller portion 41 contacts the cage ring 14, thus reducing the contact area and further reducing frictional sliding between the roller 40 and the cage ring 14. Note that if the pin portion 42 is inserted and fixed into the roller portion 41 by press-fitting as in this embodiment, it can also be used as a cam clutch unit without a cage ring. In this case, the housing (not shown) that holds the cam clutch unit itself contacts the pin portion 42 protruding outward from the roller portion 41. Therefore, even with this configuration, the pin portion 42 protruding outward from the roller portion 41 contacts the housing, reducing the contact area and thus reducing frictional sliding between the roller 40 and the housing.

[0031] (modified version) The present invention is not limited to the embodiments described above. For example, in any embodiment, the material constituting the pin portions 22, 32, and 42 is not limited to steel, but may be made of resin or non-ferrous metal. Also, in the embodiments described above, the two roller portions 21, 31, and 41 were configured to be separate from the pin portions 22, 32, and 42, but the invention is not limited to this, and one of the two roller portions 21, 31, and 41 may be configured to be integrated with the pin portions 22, 32, and 42, while the other roller portion 21, 31, and 41 is provided as a separate component. Even when one roller portion 21, 31, and 41 and the pin portions 22, 32, and 42 are integrated and made of the same material, the diameter of the pin portions 22, 32, and 42 can be arbitrarily set by omitting the other roller portion 21, 31, and 41. [Explanation of symbols]

[0032] 10 Cam Clutch Unit 11 Cam 12 Springs 13 Pocket section 14 Cage Rings 20, 30, 40 Laura 21, 31, 41 Roller section 22, 32, 42 pin section 23, 33, 43 grooves 210, 310, 410 end face 211, 411 through holes 212 Roller surface 221, 321 End 311 Recess 312 End face

Claims

1. A cam clutch unit comprising at least a plurality of cams positioned between an inner ring and an outer ring that are coaxially rotatable relative to each other, and an annular spring that biases the cams, A roller disposed together with the cam between the inner ring and the outer ring, The roller comprises a pair of roller sections and a pin section provided between the roller sections, characterized in that at least one of the roller sections and the pin section are separate.

2. The roller according to claim 1, wherein the roller portion, which is separate from the pin portion, is provided with a through hole that penetrates its end face, and the pin portion is inserted into the through hole.

3. The roller according to claim 1, wherein the roller portion, which is separate from the pin portion, has a recess formed on one end face thereof, and the pin portion is inserted into the recess.

4. The roller according to claim 2, characterized in that the pin portion is inserted so as to penetrate the through hole and protrude outward from the outer end face of the roller portion.

5. The roller according to claim 1, characterized in that the pin portion is provided with respect to the roller portion by gap fitting.

6. The roller according to claim 1, characterized in that each of the roller portion and the pin portion are separate from each other.

7. A cam clutch unit characterized by comprising at least a plurality of cams disposed between an inner ring and an outer ring that are coaxially rotatable relative to each other, a roller according to any one of claims 1 to 6, and an annular spring for biasing the cams.

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