Cam clutch unit

Abstract

An object of the present invention is to provide a cam clutch assembly which can improve torque transmission efficiency by improving ease of assembly and workability, while preventing a cam from falling out of a cage ring and a preload member from being damaged during assembly.The object is achieved by a cam formed to have a head portion and a leg portion formed to have respective maximum cross-sectional widths Wa and Wb larger than an opening width Wp of a pocket portion of a cage ring, so that the head portion and / or the leg portion of the cam can pass through the pocket portion by rotating the cam while inserting the cam, which is in an inclined posture, into the pocket portion along an opening direction thereof, and thereby elastically deforming the pocket portion.

Description

BACKGROUND OF THE INVENTION1. Field of the InventionThe present invention relates to a cam clutch unit that transmits and interrupts torque between an input shaft and an output shaft.2. DESCRIPTION OF THE RELATED ARTFor example, as illustrated in FIG. 15, a cam clutch unit is known which is configured to include a plurality of cams 210 disposed between an inner race and an outer race that are coaxially provided to be relatively rotatable with respect to each other, a cage ring 220 having a plurality of pocket portions 225 that restrict relative movement of the cams 210 in a circumferential direction, and an annular spring serving as a biasing member 230 mounted in a mounting groove 213 formed in an outer circumferential side cam surface of each of the cams 210 in the circumferential direction to bias each of the cams 210 and bring each of the cams 210 into contact with the inner race and the outer race (see, for example, Japanese Patent Application Publication No. 2021-177091).Each of the cams 210 in the cam clutch unit 200 has a body portion disposed in the pocket portion 225 while being passed therethrough, a head portion continuing to an outer circumferential side of the body portion, and a leg portion continuing to an inner circumferential side of the body portion. The head portion of the cam 210 is formed such that its maximum cross-sectional width Wa corresponding to a maximum distance between two parallel lines when the head portion is held between the parallel lines is larger than a minimum opening width Wp of the pocket portion 225. Meanwhile, the leg portion of the cam 210 is configured such that its maximum cross-sectional width Wb corresponding to a maximum distance between two parallel lines when the leg portion is held between the parallel lines is smaller than the minimum opening width Wp of the pocket portion 225, so that the cam 210 can pass through the pocket portion 225 from an outer circumferential side by obliquely inserting the cam 210 into the pocket portion 225.In the cam clutch unit 200 thus configured, the cams 210 already inserted and placed in the pocket portions 225 can rotate in the pocket portions 225 and fall out of the cage ring 220 when the cams 210 are to be mounted with the cage ring 220. In addition, since the cams 210 must be obliquely inserted into the pocket portions 225, there arises a problem of being restricted in workability in assembly.Meanwhile, a cam clutch unit using a so-called snap structure for preventing cams from dropping out of pocket portions when the cams are to be mounted on a cage ring is known (see, for example, Japanese Utility Model Application No. S 63-001928).Each of the cams used in such a cam clutch unit is formed to have a head portion and a leg portion each having a maximum cross-sectional width larger than the opening width of each of the pocket portions. Accordingly, by inserting the cam into the pocket portion in the opening direction thereof under pressure, the cam is engaged with an edge portion of an opening of the pocket portion, whereby the cam can be prevented from falling out of the pocket portion.Moreover, a structure is also known in which a limiting stepped portion is provided in another end surface of a cam having a stepped portion engaged with a biasing member in an end surface thereof in an axial direction, a limiting protrusion portion limiting an inclination of the cam is provided on a surface of a pocket portion of a cage ring, the surface being adjacent to the limiting step portion of the cam in the axial direction, and the limiting step portion of the cam is engaged with the limiting step portion of the pocket portion to prevent the cam from dropping out of the cage ring (see Japanese Patent Application No. 2023-104553).SUMMARY OF THE INVENTIONThe method disclosed in Japanese Utility Model Application No. However, in the configuration described in S63-001928, a high dimensional accuracy for the opening width of the pocket portion is required due to a structural reason for the elastic deformation of the cage ring upon insertion of the cam. However, since the cage ring is made of, for example, an integrally molded product of resin, it is difficult to make the opening width of the pocket portion highly dimensional, and the insertion of the cam into the pocket portion under pressure may damage the cage ring.The structure described in Japanese Patent Application No. 2023-104553 has the following problem. First, the cam easily falls apart at the time of assembly, and it is necessary to provide an engagement structure that prevents the cam from falling down in the axial direction on one end side of the pocket portion in the axial direction. Therefore, when the cam clutch unit is to be inserted between an inner race and an outer race, the spring held between the cam and the cage ring in the axial direction may be damaged, so that an appropriate biasing force on the cam cannot be obtained. Moreover, in a structure in which the limiting step portion of the cam and the limiting step portion of the pocket portion are to be engaged with each other, it is necessary to provide the cam and the cage ring with the limiting step portions, respectively, which increases the number of processing steps and the cost. In addition, since the cam needs to be obliquely inserted into the pocket portion, the assembly workability is lowered.The present invention has been made based on the above-described circumstances, and an object thereof is to provide a cam clutch unit capable of improving torque transmission efficiency by improving ease of assembly and workability while preventing a cam from dropping out of a cage ring and damaging a biasing member during assembly.The present invention solves the above-described problems by providing a cam clutch unit including a plurality of cams disposed between an inner race and an outer race that are coaxially rotatable with respect to each other, a cage ring made of a resin and having a plurality of pocket portions that restrict relative movement of the cams in a circumferential direction, and a biasing member that biases the cams so as to bring the cams into contact with the inner race and the outer race, each of the cams being formed to have a body portion that is disposed in the pocket portion while being inserted therethrough and a head portion that continues to an outer circumferential side of the body portion and further having a leg portion that continues to an inner circumferential side of the body portion, having a dimension in an axial direction that is smaller than a dimension of the pocket portion in the axial direction, wherein both the head portion and the leg portion are formed such that a maximum cross-sectional width thereof corresponding to a maximum distance between two parallel lines when both the head portion and the leg portion are held between the two parallel lines is larger than an opening width of the pocket portion in a cross section perpendicular to a rotation center of the cam, wherein the head portion and / or the leg portion is formed to be able to pass through the pocket portion by rotating the cam while the cam that is in an inclined position is inserted into the pocket portion along an opening direction of the pocket portion, thereby elastically deforming the pocket portion.According to a first aspect of the present invention, the cam and the pocket portion of the cage ring are formed to be snap-connected to each other by rotating the cam during insertion of the cam into the pocket portion upon assembly. Therefore, it is possible to mount the cam on the cage ring without damaging the cage ring while the cam is inserted into the pocket portion along its opening direction, and prevent the cam from falling down.Since the cam and the pocket portion form a snap connection, it is not necessary to separately provide the cam and the cage ring with corresponding structures that prevent the cam from falling out. This can reduce the labor. Moreover, it is possible to avoid the occurrence of a problem in which, when the cam clutch unit is to be inserted between the inner race and the outer race, the biasing member is held between the cam and the cage ring in the axial direction so as to be damaged, and accordingly, it is possible to allow the biasing member to bias the cam with an appropriate biasing force and improve torque transmission. In addition, since high dimensional accuracy is not required for the pocket portion, flexibility in assembly can be improved.According to a second aspect of the present invention, when the cam is inserted into the pocket portion, an amount (snap amount) of elastic deformation of the pocket portion can be reduced, so that the cam can be easily mounted to the cage ring.According to a third aspect of the present invention, when the cam is inserted into the pocket portion, the cam can be more easily mounted to the cage ring by moving the cam along the cam insertion guide portion, which can improve ease of mounting.According to a fourth aspect of the present invention, the cam can be inserted into the pocket portion in a correspondingly inclined position, which can improve the ease of assembly.According to a fifth aspect of the present invention, the spring serving as the biasing member is no longer held between the cam and the cage ring, and thus the spring is not damaged when the cam clutch unit is inserted between the inner race and the outer race.According to a sixth aspect of the present invention, the roller pocket portion of the cage ring has the surface adjacent to the roller, the roller pocket portion is formed to restrict the movement of the roller toward the outer race and toward the inner race, and therefore it is possible to prevent the roller from falling down toward the outer circumferential side during assembly and improve ease of assembly. Moreover, a simple columnar or cylindrical roller that does not need to be machined can be used as the roller, which reduces the machining effort.BRIEF DESCRIPTION OF THE DRAWINGSFIG. 1 is a perspective view showing a configuration of a cam clutch unit according to a first embodiment of the present invention; FIG. 2 is a perspective view showing a configuration of a cage ring in the cam clutch unit illustrated in FIG. 1 ; FIG. 3 is an end face view showing a configuration of the individual cams in the cam clutch unit shown in FIG. 1; FIG. 4A is a diagram showing a configuration of a head portion of the cam; FIG. 4B is a diagram showing a configuration of a leg portion of the cam; FIG. 5 is a partial cross-sectional view along a rotational axis schematically showing the configuration of the cam clutch unit illustrated in FIG. 1 ; FIG. 6A is a schematic diagram schematically illustrating a step of assembling the cam to the cage ring, showing a state in which the cam is inserted into a pocket portion; FIG. 6B is a schematic diagram schematically illustrating a step of mounting the cam to the cage ring, showing a state in which the cam whose leg portion is partially inserted into the pocket portion is rotated; FIG. 6C is a schematic diagram schematically illustrating a step of mounting the cam on the cage ring, showing a state in which the leg portion of the cam has passed through the pocket portion; FIG. 7 is a perspective view showing a part of a configuration of the cage ring in another example; FIG. 8 is a partial cross-sectional view showing a configuration of the cage ring in another example; FIG. 9 is a perspective view showing a configuration of a cam clutch unit according to a second embodiment of the present invention; FIG. 10 is a side view of the cam clutch unit illustrated in FIG. 9 ; FIG. 11 is a perspective view showing a configuration of a cage ring in the cam clutch unit illustrated in FIG. 9 ; FIGS. 12A and 12B are a side view and an end face view each showing a configuration of the individual cams in the cam clutch unit shown in FIG. 9 ; FIG. 13 is a partial cross-sectional view along a rotational axis schematically showing the configuration of the cam clutch unit illustrated in FIG. 9 ; FIG. 14 is a partial cross-sectional view showing a part of a cross section taken along line A-A in FIG. 10 ; and FIG. 15 is a cross-sectional view perpendicular to the rotational axis, showing a schematic configuration of an example of a conventional cam clutch unit.DESCRIPTION OF THE PREFERRED EMBODIMENTSNext, a cam clutch unit according to the present invention will be described with reference to the drawings.As illustrated in FIG. 1, a cam clutch unit 100 according to a first embodiment of the present invention includes a plurality of cams 110 disposed in an annular space between respective raceway surfaces of an inner race and an outer race that are coaxially provided so as to be relatively rotatable with respect to each other, a cage ring 120 having a plurality of pocket portions 125 that restrict the relative movement of the cams 110 in a circumferential direction, and a biasing member 130 that biases each of the plurality of cams 110 in a direction of engagement with the inner race and the outer race to bring the cam 110 into contact with the inner race and the outer race.First, a specific description will be given of the configuration of the cage ring 120. As illustrated in FIG. 2, the cage ring 120 includes an annular plate 121 on one end side and an annular plate 122 on the other end side that are disposed so as to oppose each other in the axial direction, and a plurality of columnar ribs 123 that connect the annular plate 121 on the one side and the annular plate 122 on the other side. An inner diameter of the annular plate 121 on the one side is larger than an outer diameter of the annular plate 122 on the other side, each of the ribs 123 has one end portion in the axial direction fixed to an inner circumferential surface of the annular plate 121 on the one side and another end portion in the axial direction fixed to an outer circumferential surface of the annular plate 122 on the other side, and the annular plate 121 on the one side forms a radially outward protruding flange portion around an entire circumference in the circumferential direction.The individual ribs 123 are aligned equidistantly in the circumferential direction, and the pocket portions 125 are formed between the adjacent ribs 123. In the present embodiment, as illustrated in FIG. 3, each of the ribs 123 is formed to have a substantially trapezoidal cross-sectional shape such that a width dimension thereof decreases radially inward, while each of the pocket portions 125 is formed to have a rectangular opening shape and an opening width Wp that is uniform in a radial direction.As illustrated in FIG. 3, each of the plurality of cams 110 has a body portion 115 disposed in the pocket portion 125 of the cage ring 120 while being passed therethrough, a head portion 111 continuing to an outer circumferential side of the body portion 115, and a leg portion 116 continuing to an inner circumferential side of the body portion 115. Note here that, in a state where the cam 110 is interposed between the inner race and the outer race, the head portion 111 refers to a portion of the cam 110 protruding from an opening edge of the pocket portion 125 toward the outer circumferential side, while the leg portion 115 refers to a portion of the cam 110 protruding on the outer circumferential side from the opening edge of the pocket portion 125. In the present embodiment, the body portion 115 is formed to have a columnar shape having a uniform width dimension in the radial direction, but may be formed to have a shape having a width dimension varying in the radial direction.The head portion 111 of the cam 110 is formed to have an outer circumferential side cam surface 112 that engages with the raceway surface of the outer race so that a maximum cross-sectional width Wa thereof corresponding to a maximum distance between two parallel lines when the head portion 111 is held between the two parallel lines is larger than the opening width Wp of the pocket portion 125 in a cross section perpendicular to a rotation center of the cam 110. Moreover, in the present embodiment, as illustrated in FIG. 4A, the head portion 111 of the cam 110 is formed such that its width W 1 in a first inclination direction and its width W 2 in a second inclination direction are each larger than the opening width Wp of the pocket portion 125. The width W 1 in the first inclination direction mentioned here refers to a width corresponding to a minimum distance between two straight lines which are a first virtual straight line L 1 connecting any two points a 1 and b 1, whose smallest distance in a head portion side region extending from the head portion 111 to the body portion 115 via a side surface of the cam 110 is the same dimension as a thickness t of the pocket portion 125, and a straight line parallel to the first virtual straight line L 1 when another side region of the head portion 111 is held between the two straight lines. The width W 2 in the second inclination direction refers to a width corresponding to a minimum distance between two straight lines which are a second virtual straight line L 2 connecting any two points a 2 and b 2 whose smallest distance in a head portion side region extending from the head portion 111 to the body portion 115 via another side surface of the cam 110 has the same dimension as the thickness t of the pocket portion 125, and a straight line parallel to the second virtual straight line L 2 when a side region of the head portion 111 is held between the two straight lines.As shown in FIG. 3, the leg portion 116 of the cam 110 has an outer peripheral side cam surface 117 that engages with the raceway surface of the inner race and is formed such that a maximum cross-sectional width Wb thereof corresponding to a maximum distance between two parallel lines when the leg portion 116 is held between the two parallel lines is larger than the opening width Wp of the pocket portion 125 in a cross section perpendicular to the rotational center of the cam 110.Moreover, in the present embodiment, as illustrated in FIG. 4B, the leg portion 116 of the cam 110 is formed such that each of the width W 3 in a third inclination direction and a width W 4 in a fourth inclination direction is larger than the opening width Wp of the pocket portion 125. Note that the width W 3 in the third inclination direction refers to a width corresponding to a minimum distance between two straight lines, which are a third virtual straight line L 3 connecting any two points c 1 and d 1, the smallest distance of which in a leg portion side region extending from the body portion 115 to the leg portion 116 across the one side surface of the cam 110 is the same dimension as the thickness t of the pocket portion 125, and a straight line parallel to the third virtual straight line L 3 when another side region of the leg portion 116 is held between the two straight lines. The width W 4 in the fourth inclination direction is a width corresponding to a minimum distance between two straight lines, which are a fourth virtual straight line L 4 connecting any two points c 2 and d 2 whose smallest distance in a leg portion side region extending from the body portion 115 to the leg portion 116 via the other side surface of the cam 110 is the same dimension as the thickness t of the pocket portion 125, and a straight line parallel to the fourth virtual straight line L 4 when a side region of the leg portion 116 is held between the two straight lines.In the present embodiment, each of the cams 110 is configured such that both end surfaces thereof in the axial direction are formed flat and have an axial direction dimension smaller than a axial direction dimension of each of the pocket portions 125. Consequently, upon assembly, the cam 110 can approach the pocket portion 125 while being in a position in which its both end surfaces extend in an opening direction (radial direction) of the pocket portion 125 without being inclined with respect to the axial direction.In a state where the cam 110 is placed in the pocket portion 125, a position of the cam 110 in the circumferential direction is restricted by the rib 123, and as illustrated in FIG. 5, a position of the cam 110 in the axial direction is restricted by the annular plate 121 at one end and the annular plate 122 at the other end.In the present embodiment, the biasing member 130 is made of an annular spring and is mounted in a mounting groove 113 formed in the head portion 111 of each of the cams 110.The mounting groove 113 is formed at a central portion in the axial direction, and as a result of mounting the biasing member 130, a side portion of the mounting groove 113 is pressed toward the inner peripheral side, and thus the cam 110 is rotated in an engagement direction (e.g., a clockwise direction in FIG. 3 ) to be biased in a state where the cam 110 is in contact with the inner race and the outer race.As described above, in the present embodiment, the head portion 111 and the leg portion 116 of the cam 110 are configured such that the width W 1 in the first inclination direction, the width W 2 in the second inclination direction, the width W 3 in the third inclination direction, and the width W 4 in the fourth inclination direction are each larger than the opening width Wp of the pocket portion 125. As a result, even when the cam 110 is at an arbitrary position, the head portion 111 and the leg portion 116 of the cam 110 are formed so as not to pass through the pocket portion 125 by merely inserting the cam 110 into the pocket portion 125 along the opening direction (radial direction) thereof or by merely moving the cam 110 placed in the pocket portion 125 in the radial direction during assembly.Therefore, in the cam clutch unit 100 according to the present embodiment, each of the width W 1 in the first inclination direction, the width W 2 in the second inclination direction, the width W 3 in the third inclination direction, and the width W 4 in the fourth inclination direction is provided with a dimension that allows the pocket portion 125 to be elastically deformed by rotating the cam 110 while the cam 110 is inserted into the pocket portion 125 in an inclined position along the opening direction of the pocket portion 125. In other words, both the head portion 111 and the leg portion 116 of the cam 110 and the pocket portion 125 form a snap-in structure, and accordingly, even when the cam 110 is inserted into the pocket portion 125 from either the head portion 111 side or the leg portion 116 side, it is possible to mount the cam 110 to the cage ring 120, and even when the cam 110 rotates in the pocket portion 125 to an arbitrary position, the cam 110 can be prevented from falling down.As long as at least one of the width, the width W 1 in the first inclination direction, the width W 2 in the second inclination direction, the width W 3 in the third inclination direction, and the width W 4 in the fourth inclination direction is sized so that the pocket portion 125 can be elastically deformed by rotating the cam 110 while the cam 110 in the inclined posture is inserted into the pocket portion 125 along its opening direction, it is possible to mount the cam 110 to the cage ring 120, and even if the cam 110 in the pocket portion 125 is rotated to any posture, it is possible to prevent the cam 110 from dropping.An example of a method of assembling the cam 110 to the cage ring 120 will be described below. As illustrated in FIG. 6A, the cam 110 in the inclined position obtained by rotating the cam 110 in a disengagement direction is inserted from the leg portion 116 into the pocket portion 125 along the opening direction of the pocket portion 125. At this time, the width W 4 of the cam 110 in the fourth inclination direction is larger than the opening width Wp of the pocket portion 125, and accordingly, the leg portion 116 of the cam 110 does not pass through the pocket portion 125 to be brought into a state of being engaged with the opening edge of the pocket portion 125. In this state, as illustrated in FIG. 6B, the cam 110 is rotated in the engagement direction by using a contact point between another side surface of the body portion 115 of the cam 110 and the opening edge of the pocket portion 125 as a fulcrum to elastically deform the pocket portion 125 and establish a state in which the cam 110 can pass through the pocket portion 125. As shown in FIG. 6C, it is then possible to connect the cam 110 to the cage ring 120 by further inserting the cam 110. In a state where the cam 110 is placed in the pocket portion 125, each of the width W 1 in the first inclination direction, the width W 2 in the second inclination direction, the width W 3 in the third inclination direction, and the width W 4 in the fourth inclination direction of the cam 110 is larger than the opening width Wp of the pocket portion 125, and therefore the cam 110 is prevented from dropping out of the pocket portion 125 even when the cam 110 is rotated in the pocket portion 125 to an arbitrary position when another cam 110 is to be mounted to the cage ring 120.While the case where the cam in the inclined position obtained by rotating the cam 110 in the disengagement direction is inserted into the pocket portion 125 from the leg portion 116 side has been described so far, the cam 110 may be inserted into the pocket portion 125 from the head portion 111 side of the cam 110. Alternatively, it is also possible to insert the cam 110 in the inclined position obtained by rotating the cam 110 in the direction of engagement with the pocket portion 125 from the head portion 111 or the leg portion 116 side.In the cam clutch unit 100 according to the present embodiment, the cam 110 and the pocket portion 125 of the cage ring 120 are formed to be locked to each other by rotating the cam 110 during the insertion of the cam 110 into the pocket portion 125 upon assembly. Accordingly, in the cam clutch unit 100 according to the present embodiment, it is possible to easily mount the cam 110 to the cage ring 120 without damaging the cage ring 120 while the cam 110 is inserted into the pocket portion 125 along its opening direction, and prevent the cam 110 from dropping.Since the cam 110 and the pocket portion 125 form the snap connection, it is not necessary to separately provide the cam 110 and the cage ring 120 with corresponding structures that prevent the cam 110 from falling out. Therefore, it is possible to reduce the machining amount.Moreover, the biasing member 130 is mounted in the mounting groove 113 provided at a center portion of the cam 110 in the axial direction, and accordingly, it is possible to avoid occurrence of a problem in which, when the cam clutch unit 100 is to be inserted between the inner race and the outer race, the biasing member 130 is held between the cam 110 and the cage ring 120 in the axial direction, thereby being damaged. Thereby, it is possible to use the biasing member 130 to apply an appropriate biasing force to the cam 110 and bias the cam 110 and improve torque portability. In addition, since high dimensional accuracy is not required for the pocket portion 125, flexibility in assembly can be improved.The cage ring 120 may also be formed to have a cam insertion guide portion on at least one side of the opening edge of the pocket portion 125 in the circumferential direction. With such a configuration, when the cam 110 is to be inserted into the pocket portion 125, the cam 110 can be more easily assembled to the cage ring 120 by moving the cam 110 along the cam insertion guide portion, which can facilitate assembly.Specifically, for example, when the cam 110 is to be mounted to the pocket portion 125 from the side of the leg portion 116, a cam insertion guide portion 126 is formed by providing each of two side edges of an outer surface of the rib 123 with a C-shaped chamfer as illustrated in FIG. 7. It is also possible that only one side edge of the outer surface of the rib 123 is formed to have the C-shaped chamfer, or that the side edge of the outer surface of the rib 123 has an R-shaped shape and not the C-shaped chamfer. When the cam 110 is to be installed into the pocket portion 125 from the head portion 111 side, the cam insertion guide portion may be provided suitably at at least one of side edges of an inner surface of the rib 123.The cage ring 120 may also be formed to have, at an opening edge portion of the pocket portion 125, a cam insertion position stabilizing portion that comes into contact with one side surface or the other side surface of the body portion 115 when the cam 110 is placed in an inclined position upon insertion of the cam 110 into the pocket portion 125. Such a configuration enables the cam 110 to be inserted into the pocket portion 125 at an appropriate inclination and can facilitate assembly.Specifically, for example, when the cam 110 is to be mounted in an inclined position obtained by rotating the cam 110 in the disengagement direction toward the pocket portion 125 from the side of the leg portion 116, as shown in FIG. 8, a side edge of the outer surface of the rib 123 is provided with a plate-like guide member inclined with respect to the opening direction of the pocket portion 125 so as to extend so as to form a cam insertion position stabilizing portion 127. It goes without saying that the position at which the guide member is to be attached may be changed accordingly depending on the installation direction of the cam 110.Alternatively, it is also possible to employ a configuration in which, in the cage ring 120 having the configuration shown in FIG. 8, the cam insertion guide portion is provided at a side edge of the rib 123 opposite to the guide member-provided side edge.While the embodiment of the present invention has been described in detail above, the present invention is not limited to the above embodiment, and the cam clutch unit according to the present invention may also be configured such that, for example, in the cam clutch unit 100 illustrated in FIG. 1, some of the plurality of cams 110 are replaced with freely rotatable rollers to ensure coaxiality of the inner race and the outer race. Next, a cam clutch unit having such a configuration according to a second embodiment of the present invention will be described.As illustrated in FIGS. 9 and 10, the cam clutch unit 100 according to the second embodiment of the present invention includes a plurality of rollers 140 that are, together with the plurality of cams 110, rotatable with respect to each other in an annular space between respective raceway surfaces of an inner race and an outer race that are provided coaxially. The respective number of the cams 110 and the rollers 140 and their arrangement can be arbitrary.As illustrated in FIG. 11, the cage ring 120 has cam pocket portions 125 athat restrict the relative movement of the cams 110 in a circumferential direction and roller pocket portions 125 bthat contain the rollers 140 to restrict the relative movement of the rollers 140 in the circumferential direction.As illustrated in FIGS. 12A and 12B, each of the plurality of cams 110 has the same configuration as each of the cams 110 in the cam clutch unit 100 according to the first embodiment described above, except that the cam 110 has, on one of its end surfaces in the axial direction, a biasing member-engaging stepped portion 118 engageable with an annular spring serving as a biasing member 130.In the present embodiment, the biasing member engaging stepped portion 118 is formed to be inclined from one side surface of the cam 110 to another side surface thereof toward an inner circumferential side in the radial direction. As a result of the mounting of the biasing member 130, a side portion of the mounting groove 113 is pressed toward the inner peripheral side to rotate the cam 110 in an engagement direction (clockwise in FIG. 12B ) and bias the cam 110 in a state where the cam 110 is in contact with the inner race and the outer race.Each of the both end surfaces of the cam 110 in the axial direction is formed flat so that the cam 110 can approach the cam pocket portion 125 awhile being in a position in which the both end surfaces extend in the opening direction (radial direction) of the pocket portion 125 without being inclined in the axial direction during assembly.In a state where the cam 110 is placed in the cam pocket portion 125 a, a position of the cam 110 in the circumferential direction is restricted by the rib 123, while as illustrated in FIG. 13, a position of the cam 110 in the axial direction is restricted by the annular plate 121 at one end and the annular plate 122 at the other end provided in the flange portion.Each of the plurality of rollers 140 has a simple cylindrical or columnar shape having no groove or stepped portion, and in the present embodiment, as illustrated in FIG. 10, a dimension of the roller 140 in the axial direction is equal to or smaller than a dimension of the cam 110 in the axial direction from which the biasing member engaging stepped portion 118 is excluded.In the present embodiment, the outer circumferential edge portions of both end surfaces of the roller 140 are chamfered to prevent engagement with the biasing member 130.The roller pocket portion 125 bof the cage ring 120 has a surface circumferentially adjacent to the roller 140 and shaped to restrict movement of the roller 140 toward the outer race side and the inner race side. In the present embodiment, as illustrated in FIG. 14, the roller pocket portion 125 bis formed such that the respective side surfaces of the two ribs 123 defining the roller pocket portion 125 bare provided opposite to each other with a pair of restricting portions 128 that form a columnar space that can accommodate the roller 140. The restricting portions 128 are formed such that each of the separation distances Wr 1 between their outer circumferential side end edges and the separation distances Wr 2 between their inner circumferential side end edges is smaller than the roller diameter D, and by being elastically deformed when the roller 140 is inserted therebetween, the restricting portions 128 allow the roller 140 to be placed in the roller pocket portion 125 b.Moreover, as illustrated in FIG. 11, the roller pocket portion 125 bis formed so that a dimension thereof in the axial direction is smaller than a dimension of the cam pocket portion 125 ain the axial direction, and has a limiting wall portion 124 protruding from a surface of the annular plate 121 on the one side toward another end side thereof in the axial direction. Thus, the movement of the roller 140 in the axial direction is restricted by the annular plate 122 on the other side and the restricting wall portion 124.As illustrated in FIG. 13, the annular spring serving as the biasing member 130 is attached to the biasing member engaging stepped portion 118, with a gap being provided between an end surface (end surface of a portion of the cam 110 from which the biasing member engaging stepped portion 118 is recessed) of the cam 110 and an end surface of the flange portion-included annular plate 121 on the one side. As a result, the biasing member 130 is no longer held between the cam 110 and the cage ring 120, so that the biasing member 130 is not damaged when the cam clutch unit 100 is inserted between the inner and outer races.In the cam clutch unit 100 according to the present embodiment, the cam 110 and the cam pocket portion 125 a, and the roller 140 and the roller pocket portion 125 bare formed to be engaged with each other, and therefore it is possible to easily mount the cam 110 and the roller 140 without damaging the cage ring 120, while it is also possible to prevent the falling of the cam 110 and the roller 140.In addition, the cam 110 and the cage ring 120 need not be separately provided with respective structures that prevent the cam 110 from falling out, and as the roller 140, a roller having a simple columnar or cylindrical shape that does not require machining may be used, which enables reduction in machining cost.While the embodiments of the present invention have been described above in detail, the present invention is not limited to the above-described embodiments, and various designs can be realized without departing from the present invention defined in the scope of the claims.For example, in each of the above-described embodiments, it has been described that the cam 110 includes the head portion 111 and the leg portion 116 formed such that each of the widths W 1 in the first inclination direction, W 2 in the second inclination direction, W 3 in the third inclination direction, and W 4 in the fourth inclination direction is larger than the opening width Wp of the pocket portion 125, but in a case where the cam is to be mounted to the cage ring in a state where the biasing member is mounted, it may also be possible to form the head portion and the leg portion of the cam such that an inclination direction width in an inclined posture in which the cam is inclined in a direction opposite to a direction, in which the cam rotates as a result of mounting the biasing member in the cam, is smaller than the opening width of the pocket portion.Although the configuration with the ring spring as the biasing member has been described, the biasing member may be, for example, a band spring, a torsion spring, or the like. Moreover, in the above-described embodiment, with respect to the cam clutch unit according to the second embodiment, the stepped portion engaged with the biasing member is provided only on one end surface of the cam in the axial direction, but it is also possible to provide the stepped portion engaged with the biasing member on each of the two end surfaces of the cam in the axial direction and bias the cam with the two annular springs.References included in the specificationThis list of documents cited by the applicant has been produced in an automated manner and is only included for the better information of the reader. The list is not part of the German patent application or utility model application. The DPMA does not take any adhesion for any faults or omissions.Patent Literature citedJP 63-001928 [0005, 0008]JP 2023-104553

[0009]

Claims

A cam clutch unit comprising a plurality of cams disposed between an inner race and an outer race which are coaxially rotatable with respect to each other, a cage ring made of a resin and having a plurality of pocket portions which restrict relative movement of the cams in a circumferential direction, and a biasing member which biases the cams so as to bring the cams into contact with the inner race and the outer race, each of the cams being formed to have a body portion which is disposed in the pocket portion while being inserted therethrough and a head portion which continues to an outer circumferential side of the body portion and further having a leg portion which continues to an inner circumferential side of the body portion with a dimension in an axial direction, which is smaller than a dimension of the pocket portion in the axial direction, wherein both the head portion and the leg portion are formed such that a maximum cross-sectional width thereof corresponding to a maximum distance between two parallel lines when both the head portion and the leg portion are held between the two parallel lines is larger than an opening width of the pocket portion in a cross section perpendicular to a rotation center of the cam, wherein the head portion and / or the leg portion is formed to be able to pass through the pocket portion by rotating the cam while the cam which is in an inclined position is inserted into the pocket portion along an opening direction of the pocket portion, thereby elastically deforming the pocket portion.The cam clutch unit according to claim 1, wherein, in the cross section perpendicular to the rotational center of the cam, the cam has: a width W1 in the first inclination direction corresponding to a minimum distance between two straight lines, which is a first virtual straight line L1 connecting any two points whose smallest distance in a head portion-side region above a side surface of the cam is the same dimension as a thickness of the pocket portion, and a straight line parallel to the first virtual straight line L1 when another side region of the head portion is held between the two straight lines; a width W2 in the second inclination direction corresponding to a minimum distance between two lines, which are a second virtual line L2 connecting any two points whose smallest distance in a head portion side area over another side surface of the cam is the same dimension as the thickness of the pocket portion, and a line parallel to the second virtual line L2 when a side area of the head portion is held between the two lines; a width W 3 in the third inclination direction corresponding to a minimum distance between two lines, which are a third virtual line L 3 connecting any two points whose smallest distance in a leg portion side area above the one side surface of the cam is the same dimension as the thickness of the pocket portion, and a line parallel to the third virtual line L 3 when another side area of the leg portion is held between the two lines; and a width W 4 in the fourth inclination direction corresponding to a minimum distance between two lines, which are a fourth virtual line L 4 connecting any two points whose smallest distance in a leg portion side area above the other side surface of the cam has the same dimension as the thickness of the pocket portion, and a line parallel to the fourth virtual line L 4 when a side area of the leg portion is held between the two lines; and at least one of the widths, the width W 1 in the first inclination direction, the width W 2 in the second inclination direction, the width W 3 in the third inclination direction, and the width W 4 in the fourth inclination direction has a dimension that allows the pocket portion to be elastically deformed when the cam is inserted into the pocket portion.The cam clutch unit according to claim 1, wherein the cage ring has a cam insertion guide portion at least on a circumferential direction side of an opening edge of the pocket portion.The cam clutch unit according to claim 1, wherein the cage ring has a cam insertion position stabilizing portion at an opening edge portion of the pocket portion, which comes into contact with a side surface or another side surface of the body portion when the cam is placed in an inclined position upon insertion of the cam into the pocket portion.The cam clutch unit according to claim 1, wherein the cam has, at one of its axial direction end surfaces, a stepped portion that engages with a biasing member, the cage ring has, at one axial direction end portion, a radially outward protruding flange portion around an entire circumference in the circumferential direction, and the biasing member is formed of an annular spring that is attached to the stepped portion that engages with the biasing member in a state in which a gap is formed between the one end surface of the cam and one end surface of the flange portion.The cam clutch unit according to claim 1, further comprising: a plurality of rollers disposed between the inner race and the outer race, the cage ring having a roller retaining pocket portion having a surface circumferentially adjacent to each of the rollers, the roller retaining pocket portion being shaped to restrict movement of the roller toward the outer race side and the inner race side, and the roller retaining pocket portion being configured to be elastically deformed when the roller is inserted into the roller retaining pocket portion along an opening direction of the roller retaining pocket portion, so that the roller can be placed in the roller retaining pocket portion.

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