Cam clutch unit

Abstract

The invention provides a cam clutch unit, which has the advantages that the machining time is reduced, the difficulty is reduced, the rotation resistance of a roller can be reduced, the freedom degree of the position of the roller is high, the roller can be arranged at the optimal position, and the weight can be reduced. Specifically, the present invention is provided with: a plurality of cams and a plurality of rollers arranged between an inner ring and an outer ring so as to be arranged in the circumferential direction; a spacer ring having a plurality of recess portions for restricting the relative movement of the cam and the roller in the circumferential direction; and a ring-shaped spring for urging the cam, the cam having an engagement portion capable of engaging with the spring, the recess portion for accommodating the roller being provided at a position where interference does not occur in the axial direction with respect to the spring, and the recess portion being arranged on both sides of the spring in the circumferential direction differently.

Description

Technical Field

[0001] The present invention relates to a cam clutch unit for transmitting and cutting off torque between an input shaft and an output shaft. Background Art

[0002] As a cam clutch, it is known that it includes: a plurality of cams arranged between an inner ring and an outer ring that are arranged to be relatively rotatable on the same axis; a spacer ring having a plurality of notches for limiting the relative movement of the cams in the circumferential direction; and an annular spring for applying force to the cams (see patent document 1, etc.).

[0003] In such a cam clutch, in order to ensure the coaxiality of the inner ring and the outer ring, it is considered to replace part of the multiple cams with freely rotatable rollers.

[0004] For example, Figures 9 to 13 As shown, the cam clutch unit 500 is configured such that a plurality of cams 530 and a plurality of rollers 540 are circumferentially arranged between an inner ring and an outer ring which are arranged to be coaxially rotatable relative to each other, the cams 530 and the rollers 540 are accommodated in the recessed portion 551 of the spacer ring 550, and the circumferential relative movement of the cams 530 and the rollers 540 is restricted.

[0005] The cam 530 and the roller 540 have circumferential grooves 535 and 545 , respectively. An annular spring 560 is accommodated in the grooves 535 and 545 , and is configured to bias the cam 530 and the roller 540 toward the inner circumference.

[0006] Patent Literature

[0007] Patent Document 1: Japanese Patent Application Publication No. 2005-106135 Summary of the invention

[0008] Since such a cam clutch unit has a circumferential groove portion in the center of the cam and the roller for accommodating an annular spring, the cam and the roller require a material that is more wear-resistant or impact-resistant. Therefore, there is a problem that the processing time and difficulty during the manufacture of the cam and the roller are long, and there are restrictions on the width dimension during processing, which makes it impossible to thin them.

[0009] In addition, although the roller is only restricted in the axial direction and needs to rotate freely, there is a problem that a non-negligible rotational resistance is generated during high-speed rotation due to frictional sliding between the bottom or side of the groove and the spring. Moreover, since the spring deteriorates due to wear, it may affect the life of the cam clutch itself.

[0010] Furthermore, even when the cam is axially long, the axial position of the roller is limited by the position of the spring and therefore cannot be set only at the optimum axial position. Also, when the axially long roller covers the optimum position, excess rolling resistance may be generated.

[0011] The purpose of the present invention is to solve the above-mentioned problems. The technical problem to be solved is to provide a cam clutch that has less processing time and reduced difficulty during manufacturing, and can reduce the rotational resistance of the roller. The position of the roller has a high degree of freedom, the roller can be configured at the optimal position, and a lightweight cam clutch unit can be achieved.

[0012] The present invention is a cam clutch unit, comprising: a plurality of cams and a plurality of rollers, which are arranged between an inner ring and an outer ring which are arranged to be coaxially rotatable relative to each other; a spacer ring having a plurality of notches for limiting the circumferential relative movement of the cam and the rollers; and at least one annular spring for applying force to the cam. The problem can be solved by the following contents, namely, the cam has an engaging portion which can engage with the spring, the notches for accommodating the rollers are arranged at a position which will not interfere with the at least one spring in the axial direction, and the plurality of notches for accommodating the rollers are arranged differently in the circumferential direction on both sides of the at least one spring.

[0013] According to the cam clutch unit described in Technical Solution 1, since the recessed portion for accommodating the roller is set at a position where no interference will occur in the axial direction relative to at least one spring, and the recessed portions for accommodating multiple rollers are arranged differently in the circumferential direction on both sides of at least one spring, the roller can be made into a simple cylindrical shape, thereby reducing the processing time and difficulty during manufacturing.

[0014] In addition, since the axial position of the recessed portion for receiving is not restricted by the position of the spring, the number of circumferential rollers can be configured differently according to the axial position, so the position of the rollers has a high degree of freedom, the rollers can be configured at the optimal position, and lightweight can be achieved.

[0015] Furthermore, the roller can be arranged at a position where it does not slide on the spring, thereby reducing the rotation resistance of the roller.

[0016] According to the structure described in Technical Solution 2, since the recessed portions for accommodating the rollers are alternately arranged in the circumferential direction on both sides of the axial direction relative to at least one spring, the axial length of the rollers can be reduced and weight can be reduced without reducing the number of rollers arranged in the circumferential direction, and the load can be evenly shared on both sides of the axial direction relative to the spring.

[0017] According to the structure described in the third technical solution, since the recessed portion for accommodating the roller is provided only on one side of the axial direction relative to at least one of the springs, the roller can be arranged only at the position that bears the most load in the axial direction, thereby suppressing the excess rolling resistance and achieving lightweight.

[0018] According to the structure described in claim 4, since the springs are provided at two or more different positions in the axial direction, the rollers can be freely arranged on both sides of each spring, thereby improving the degree of freedom.

[0019] According to the structure described in claim 5 of the present invention, since the spacer ring has the lubrication adjustment portion at a position opposite to at least one of the notches with the spring interposed therebetween, the lubrication performance can be improved.

[0020] According to the configuration described in Technical Solution 6, part or all of the recess for accommodating the roller is configured to be included in a range different from that of the recess for accommodating the cam in the axial direction, thereby further improving the freedom of roller configuration and enabling the roller to be configured in the optimal position. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a perspective view of a cam clutch unit according to a first embodiment of the present invention.

[0022] Figure 2 yes Figure 1 A perspective view of the spacer ring of the cam clutch unit is shown.

[0023] Figure 3 yes Figure 1 A three-dimensional view of the cam and rollers of the cam clutch unit is shown.

[0024] Figure 4 It is a perspective view of a cam clutch unit according to a second embodiment of the present invention.

[0025] Figure 5 It is a perspective view of a cam clutch unit according to a third embodiment of the present invention.

[0026] Figure 6 It is a perspective view of a cam clutch unit according to a fourth embodiment of the present invention.

[0027] Figure 7 It is a perspective view of a cam clutch unit according to a fifth embodiment of the present invention.

[0028] Figure 8 It is a perspective view of a cam clutch unit according to a sixth embodiment of the present invention.

[0029] Fig. 9 It is a perspective view of a conventional cam clutch unit.

[0030] Fig.10 yes Fig. 9 The cam clutch unit is shown in a side view, viewed in the direction of the axis of rotation.

[0031] Fig.11 yes Fig. 9 A side view and a front view of a cam of a cam clutch unit are shown.

[0032] Fig.12 yes Fig. 9 Side and front views of the rollers of the cam clutch unit are shown.

[0033] Fig.13 yes Fig. 9 A partial side view and a cross-sectional view of the cam clutch unit are shown.

[0034] Explanation of symbols

[0035] 100, 500-cam clutch unit; 130, 530-cam; 131-engaging portion; 535-groove portion; 140, 540-roller; 545-groove portion; 150, 550-spacer ring; 151, 551-notch portion (for cam); 152, 552-notch portion (for roller); 153-lubrication adjustment portion; 154-oil flow hole; 157-claw portion; 160, 560-spring; 161-second spring. DETAILED DESCRIPTION

[0036] The cam clutch unit 100 according to the first embodiment of the present invention is arranged in an annular space between the raceway surface of the inner ring and the raceway surface of the outer ring which are arranged to be relatively rotatable on the same axis. Figures 1 to 3 As shown, it comprises: a plurality of cams 130 as engaging parts for transmitting and cutting off torque between the inner ring and the outer ring (not shown); a plurality of rollers 140 for allowing the inner ring and the outer ring to rotate freely; a spacer ring 150 having a plurality of notches 151, 152 for limiting the circumferential relative movement of the cams 130 and the rollers 140; and an annular spring 160 for applying force to each of the plurality of cams 130 in the meshing direction relative to the inner ring and the outer ring.

[0037] like Figure 3 As shown, each of the plurality of cams 130 has a groove-shaped engaging portion 131 that can engage with the annular spring 160 at a central portion in the axial direction.

[0038] In this embodiment, as mentioned above Figures 9 to 13 As shown, similar to the cam clutch unit 500, the engaging portion 131 is formed into an inclined shape with a convex portion at an eccentric position. Since the spring 160 presses the convex portion of the engaging portion 131, the cam 130 is forced toward the inner ring side and the cam 130 is forced to swing in the working direction.

[0039] like Figure 3 As shown in FIGS. 1 and 2 , the plurality of rollers 140 do not have grooves or stepped portions. In the present embodiment, the axial dimension of the rollers 140 is less than the axial dimension of one side of the cam 130 excluding the engaging portion 131 .

[0040] In the present embodiment, the outer peripheral edge portions of both end surfaces of the roller 140 are chamfered, so that the cam clutch unit can be inserted more smoothly into the inner and outer rings.

[0041] The spacer ring 150 includes a notch portion 151 for accommodating the cam 130 and restricting relative movement in the circumferential direction, and a notch portion 152 for accommodating the roller 140 and restricting relative movement in the circumferential direction.

[0042] In the present embodiment, the recessed portions 151 for accommodating the cam 130 of the spacer ring 150 are evenly arranged in the circumferential direction at 8 locations, and the recessed portions 152 for accommodating the roller 140 are evenly arranged in the circumferential direction at 4 locations, and the recessed portion 152 for accommodating the roller 140 is arranged only on one side relative to the spring 160 at a position where no axial interference with the spring 160 occurs.

[0043] In each notch portion 151 , the cam 130 is restricted in radial movement by a spring 160 at the axial center portion.

[0044] In addition, a claw portion 157 is provided on the surface adjacent to the roller 140 of the recessed portion 152 for accommodating the roller 140. The claw portion 157 can be inserted into the roller 140 from the outer ring side by elastic deformation and can limit the movement in the radial direction during accommodation, thereby taking into account both the ease of insertion and the retention after insertion.

[0045] Furthermore, the spacer ring 150 is provided with a lubrication adjustment portion 153 capable of retaining a lubricant such as grease or oil at a position axially opposed to the notch portion 152 for accommodating the roller 140 with the spring 160 interposed therebetween.

[0046] By configuring in this way, for example, when the inner ring is supported on one side by a shaft extending from the left side of the figure, the roller 140 can be arranged only in the position corresponding to the right inner direction where the vibration caused by the bending of the shaft is the largest, and unnecessary increase in rolling resistance can be suppressed.

[0047] In addition, although twelve cams 130 and four rollers 140 are arranged in the present embodiment, the number and arrangement of the cams 130 and the rollers 140 may be arbitrary.

[0048] Furthermore, the cross-sectional shape of the cam 130 may be arbitrary, and may be, for example, a sprag shape.

[0049] like Figure 4As shown, the cam clutch unit 100 b according to the second embodiment of the present invention is configured such that rollers 140 are alternately arranged in the circumferential direction on both sides in the axial direction with respect to a spring (not shown).

[0050] Furthermore, in the present embodiment, the lubrication adjustment portion 153 that can hold a lubricant such as grease or oil is provided with the oil flow hole 154 , and the flow of the lubricant can be optimized.

[0051] The other configurations are the same as those of the first embodiment.

[0052] With such a configuration, for example, the rollers can be evenly arranged in the axial direction and also can be evenly arranged in the circumferential direction, and the axial length of the rollers can be shortened, thereby suppressing an unnecessary increase in rolling resistance.

[0053] like Figure 5 As shown, the cam clutch unit 100c according to the third embodiment of the present invention is configured such that the cams 130c are formed with different lengths on both sides in the axial direction with respect to the spring 160, and the roller 140c is arranged on the longer side.

[0054] The other configurations are the same as those of the first embodiment.

[0055] By changing the axial arrangement of the spring 160 as in the present embodiment, it is possible to realize an optimum design corresponding to the required axial length of the roller.

[0056] like Figure 6 As shown, in the cam clutch unit 100d according to the fourth embodiment of the present invention, cams 130d1 and 130d2 are arranged side by side in the axial direction in the notch portion 151d of the spacer ring 150d, and the cams 130d1 and 130d2 are independently urged by the spring 160 and the second spring 161, respectively.

[0057] The notches 152d1 and 152d2 of the accommodating roller 140 are configured to be alternately arranged in the circumferential direction only on the axial second spring 161 side of the spring 160 and on both sides of the axial second spring 161 at a position that does not axially interfere with the second spring 161 and the spring 160 .

[0058] The notch portion 152 d 2 disposed on the opposite side of the second spring 161 from the spring 160 and the notch portion 152 d 1 disposed at a position sandwiched between the second spring 161 and the spring 160 have the same axial length.

[0059] The roller 140 accommodated in the notch portion 152 d 2 is arranged so as to include a range different from that of the cam 130 d 2 urged by the second spring 161 in the axial direction.

[0060] like Figure 7 As shown, in the cam clutch unit 100e according to the fifth embodiment of the present invention, cams 130e1 and 130e2 are arranged side by side in the axial direction in the notch portion 151e of the spacer ring 150e, and the cams 130e1 and 130e2 are independently urged by the spring 160 and the second spring 161, respectively.

[0061] The notch 152 e for accommodating the roller 140 is configured to be arranged only on the axial side of the second spring 161 and on the axial side of the second spring 161 at a position that does not interfere with the second spring 161 and the spring 160 in the axial direction.

[0062] That is, the notch portion 152 e is arranged only at a position sandwiched between the second spring 161 and the spring 160 .

[0063] like Figure 8 As shown, in the cam clutch unit 100f according to the sixth embodiment of the present invention, cams 130f1 and 130f2 are arranged side by side in the axial direction in the notch portion 151f of the spacer ring 150f, and the cams 130f1 and 130f2 are independently urged by the spring 160 and the second spring 161, respectively.

[0064] The notch portion 152 f for accommodating the roller 140 is configured to be arranged only on the axially opposite side of the second spring 161 from the spring 160 at a position that does not interfere with the second spring 161 in the axial direction.

[0065] Furthermore, the roller 140 accommodated in the notch portion 152 f is arranged so as to include a range different from that of the cam 130 f urged by the second spring 161 in the axial direction.

[0066] By forming the cams in two rows as in the fourth to sixth embodiments, a cam clutch can be obtained which is long in the axial direction without making the cam itself longer in the axial direction, thereby improving the accuracy of the cam operation and allowing the use of a common cam.

[0067] Although the embodiments of the present invention have been described in detail above, the present invention is not limited to the above embodiments, and various design changes can be made without departing from the scope of the present invention described in the claims.

Claims

1. A cam clutch unit comprising: a plurality of cams and a plurality of rollers arranged between an inner ring and an outer ring arranged to be relatively rotatable on the same axis; a spacer ring having a plurality of notches for limiting the relative movement of the cams and the rollers in the circumferential direction; and at least one annular spring for applying force to the cams, characterized in that: The cam has an engaging portion capable of engaging with the spring. The recessed portion for accommodating the roller is provided at a position where it does not interfere with at least one of the springs in the axial direction. The plurality of notches for accommodating the rollers are arranged differently in the circumferential direction on both sides of at least one of the springs.

2. The cam clutch unit according to claim 1, characterized in that The notches for accommodating the rollers are alternately arranged in the circumferential direction on both sides in the axial direction of at least one of the springs.

3. The cam clutch unit according to claim 1, characterized in that: The notch portion for accommodating the roller is provided only on one side in the axial direction with respect to at least one of the springs.

4. The cam clutch unit according to claim 1, characterized in that: The springs are provided at two or more different positions in the axial direction.

5. The cam clutch unit according to claim 1, characterized in that: The spacer ring has a lubrication adjustment portion at a position of at least one of the notches that faces the spring.

6. The cam clutch unit according to claim 1, characterized in that: A part or all of the rollers are arranged to include a range different from that of the cam in the axial direction.

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