One-way clutch

Abstract

A one-way clutch is provided that enables miniaturization of radial dimensions and reduces assembly work. A retainer (3) is provided with a coupling portion (3b) of a clamped portion (3e) on one side and an opposite side of each columnar portion (3a) provided upright, and extends into a cylindrical shape around the shaft (7). The coupling portion (3b) is arranged on the outer periphery of the outer sleeve (4) and is disposed in the housing (2). The housing (2) has a receiving portion (2a) of the inner diameter of each outer periphery arranged to cover the retainer (3) and the outer sleeve (4). In the axial direction, a coupling portion (2f) is formed on the inner periphery to engage with the clamped portion (3e) and transmit the rotation of the retainer (3) to the housing. On one end side of the receiving portion (2a), a limiting wall (2b) that limits the movement of the internal unit (5) toward one end side of the receiving portion (2a) is formed opposite to the end face (3f) of the coupling portion (3b). A cap (6) for limiting the detachment of the internal unit (5) is fitted into the open insertion port (2c) at the other end side of the storage portion (2a).

Description

Technical Field

[0001] The present invention relates to a one-way clutch in which one-way rotation of a shaft is transmitted to a housing. Background Art

[0002] Such an existing one-way clutch is disclosed in, for example, Patent Document 1. The one-way clutch comprises an annular component and a retaining component in which a boss is embedded in a circular ring. A plurality of bosses are uprightly arranged on the end face of the main body of the retaining component in a manner surrounding an insertion hole, and the main body comprises an insertion hole in which a rotating shaft is embedded. A needle is retained in a retaining groove formed in a gap between the bosses. When the rotating shaft embedded in the insertion hole of the retaining component rotates in a clockwise direction, the tightly coupled state caused by the engagement between the inner surface of the annular component and the outer peripheral surface of the needle is not firm, so the annular component and the rotating shaft can rotate relative to each other. In addition, when the rotating shaft rotates in a counterclockwise direction, the tightly coupled state becomes firm, so the actuating component mounted on the annular component and the rotating shaft cannot rotate relative to each other, so that torque can be transmitted between the two.

[0003] The actuating member comprises an outer cylinder with a one-way clutch embedded therein, and a torque transmission member integrally formed therewith. The outer cylinder is rotatably mounted on the outer circumference of the annular member, with engaging ridges on its inner circumference engaging with notches on the outer surface of the annular member.

[0004] A conventional one-way clutch of this type is disclosed, for example, in Patent Document 2. This one-way clutch consists of a torque transmission wheel, an outer wheel, a roller, and a retainer that holds a biasing spring. The retainer is housed within the inner circumference of the outer wheel. During use, a shaft is inserted through the axially connected torque transmission wheel and outer wheel. A pair of retaining rings are embedded at each end of the one-way clutch on the outer circumference of the shaft to prevent the one-way clutch from disengaging.

[0005] Prior art literature

[0006] Patent Literature

[0007] Patent Document 1: Japanese Patent Application Laid-Open No. 11-336797

[0008] Patent Document 2: Japanese Patent Application Laid-Open No. 2010-242889 Summary of the Invention

[0009] Problems to be solved by the invention

[0010] However, the one-way clutch disclosed in the aforementioned prior art document 1 has a structure in which an engaging ridge provided on the inner circumference of the outer cylindrical body engages with a notch provided on the outer circumference of the annular member in the radial direction of the one-way clutch, and the outer cylindrical body is attached to the outer circumference of the annular member. Therefore, when the radial thickness of the annular member is reduced and the radial dimensions of the one-way clutch are miniaturized, a load from the needle is applied to the annular member, potentially damaging the annular member. This limits the ability to miniaturize the radial dimensions of the one-way clutch.

[0011] Furthermore, the one-way clutch disclosed in Prior Art Document 2 can be miniaturized in the radial direction by axially coupling the torque transmission wheel and the outer wheel. However, to prevent the torque transmission wheel and the outer wheel from coming off the shaft, the one-way clutch disclosed in Prior Art Document 2 requires a pair of retaining rings to be fitted onto both end shafts of the one-way clutch, which increases assembly time.

[0012] Means of solving problems

[0013] The present invention has been invented to solve such problems.

[0014] A one-way clutch, characterized in that it comprises the following: a retainer having a plurality of columnar portions uprightly provided on the base at prescribed intervals in the circumferential direction of a shaft passing through an inner diameter portion formed on the base; a hollow cylindrical outer sleeve, the inner circumference of which surrounds the side portions of each columnar portion uprightly provided on the base; a cylindrical rolling element rollably retained in a pocket portion, the pocket portion being formed between adjacent columnar portions and being clamped between the inner wall surface of the outer sleeve and the outer circumference of the shaft; an elastic member applying a force to the rolling element on the columnar portion side of one of the adjacent columnar portions in the pocket portion; a housing covering the outer circumference of the retainer and the outer sleeve, and transmitting one-way rotation of the shaft according to the rolling position of the rolling element in the pocket portion;

[0015] The retainer has a base on one side and the opposite side of each columnar portion, and a coupling portion provided with a clamping portion extending to form a cylindrical shape around the axis. The outer periphery of the coupling portion is arranged on the outer periphery of the outer sleeve and is coaxially arranged in the housing with the outer sleeve.

[0016] The shell has a receiving portion with an inner diameter covering each outer periphery of the arrangement of the retainer and the outer sleeve, and an engaging portion is formed on the inner periphery. The engaging portion engages with the engaged portion in the axial direction and transmits the rotation of the retainer to the shell. A limiting wall is formed on one end side of the receiving portion opposite to the end face of the coupling portion. The limiting wall limits the movement of the retainer and the outer sleeve toward one end side of the receiving portion in the axial direction. The cap is engaged with the insertion port. The insertion port is open toward the receiving portion of the retainer and the outer sleeve at the other end side of the receiving portion in the axial direction. The cap limits the detachment of the retainer and the outer sleeve from the insertion port.

[0017] According to this structure, the retainer and outer sleeve are housed in a housing portion configured to cover the inner diameter of the outer circumferences of the respective arranged retainers. Between the housing and the retainer, an engaging portion formed on the inner circumference of the housing engages with an engaged portion provided on the coupling portion in the axial direction of the housing, thereby transmitting the rotation of the retainer to the housing. Therefore, unlike the conventional one-way clutch disclosed in Patent Document 1, in which the inner circumference of the housing and the outer circumference of the outer sleeve engage in the radial direction of the one-way clutch, which limits the reduction of the radial thickness of the outer sleeve, this eliminates the need to ensure an engaging space between the engaging portion and the engaged portion in the radial direction of the one-way clutch, thereby enabling the radial dimension of the one-way clutch to be miniaturized.

[0018] Furthermore, the movement of the retainer and outer sleeve, housed in the housing's housing portion, toward one end of the housing portion in the axial direction, is restricted by a stopper wall formed on one end of the housing portion. Furthermore, a cap engages with an insertion opening located at the other end of the housing portion in the axial direction and opening toward the housing portion for the retainer and outer sleeve, thereby restricting the retainer and outer sleeve from being removed from the insertion opening. Therefore, the assembly work required to insert a pair of retaining rings into the shaft, as in the conventional one-way clutch disclosed in Patent Document 2, is no longer necessary to prevent the retainer and outer sleeve from being removed, thereby reducing assembly effort.

[0019] Furthermore, the present invention is characterized in that in the retainer, the engaging portion is formed by having the engaging portion cut out by a predetermined length in the axial direction from an end surface of the engaging portion at a plurality of locations.

[0020] According to this structure, the engaging portion is formed by having a predetermined length of cutout from the end surface of the engaging portion in the axial direction of the housing at multiple locations. This provides flexibility in a direction intersecting the axial direction. Therefore, when bending or torsional stress is applied to the housing, the engaging portion elastically deforms in response to these stresses, absorbing them. This prevents the rolling elements from tightening or slipping, preventing poor engagement of the rolling elements during the locking operation of the one-way clutch, and preventing poor rolling during the idling operation.

[0021] Furthermore, the present invention is characterized in that in the retainer, the length of the coupling portion extending from the end surface of the base on which the columnar portion is erected is set to be longer than a predetermined length of the engaged portion formed to be short by a predetermined length in the axial direction.

[0022] This structure maintains the strength of the coupling portion of the retainer, securely engages the engaged portion formed in the coupling portion with the engaging portion formed on the inner circumference of the housing, and reliably transmits the rotation of the retainer to the housing. Furthermore, the retainer can be reliably positioned relative to the housing.

[0023] In addition, it is characterized in that, in the present invention, the lengths of the engaged portion and the engaging portion are set so that when they engage with each other, a gap is generated between the end surface of the coupling portion and the limiting wall.

[0024] According to this structure, when the engaged portion and the engaging portion are engaged, the end surface of the coupling portion and the limiting wall no longer abut against each other, thereby preventing damage to the components caused by the abutment.

[0025] The retainer of the present invention is also characterized in that it is press-fitted into the outer shell, and the rectangular inner wall surface of the outer shell abuts against the periphery of the side portion having the angular column shape rising from the base of each columnar portion, thereby being fixed to the outer shell.

[0026] A gap exists between the retainer and the fixed portion of the outer sleeve, causing misalignment in the relative rotational positions of the retainer and the outer sleeve. If the positional relationship between the retainer's columnar portion and the inner wall surface of the outer sleeve changes, the rolling elements housed in the pocket portion are obstructed by the retainer's columnar portion, sometimes hindering the locking action of the rolling elements meshing between the inner wall surface of the outer sleeve and the outer periphery of the shaft. However, according to this structure, the side portions of the retainer's angular columnar raised portion, each columnar portion, abut against the rectangular inner wall surface of the outer sleeve and press into the outer sleeve. This eliminates the gap between the retainer and the fixed portion of the outer sleeve, preventing misalignment in the relative rotational positions of the retainer and the outer sleeve. Therefore, the positional relationship between the retainer's columnar portion and the inner wall surface of the outer sleeve remains unchanged at the original set position, and the locking action of the rolling elements meshing between the inner wall surface of the outer sleeve and the outer periphery of the shaft is no longer obstructed by the retainer's columnar portion. Therefore, the unidirectional rotation of the shaft can be reliably transmitted to the housing through the locking action of the rolling elements meshing between the inner wall surface of the outer sleeve and the outer periphery of the shaft.

[0027] Furthermore, in the present invention, the cap has an inner diameter portion for inserting the shaft, and the housing has inner diameter portions for inserting the shaft on the side of the housing portion where the cap fits and on the opposite side.

[0028] With this structure, the shaft is supported for rotation by being inserted through the inner diameter portion formed in the base of the retainer, the inner diameter portions of the housing on one side and the other side of the cap where the housing is located, and the inner diameter portion of the cap. This allows the shaft to rotate stably without shaking.

[0029] Furthermore, the present invention is characterized in that the outer peripheral surface of the outer sleeve is formed into a shape in which arc surfaces and flat surfaces are alternately arranged.

[0030] According to this structure, the outer sleeve can be easily positioned during automatic assembly of the one-way clutch.

[0031] Effects of the Invention

[0032] According to the present invention, it is possible to provide a one-way clutch that can be reduced in radial dimension and has a reduced assembly work. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 (a) is a front view of a one-way clutch according to an embodiment of the present invention, Figure 1 (b) is a perspective view of a broken cross section of the one-way clutch.

[0034] Figure 2 (a) is the composition Figure 1 A front view of the housing of the one-way clutch is shown, Figure 2 (b) is a cross-sectional perspective view of the broken shell.

[0035] Figure 3 (a) is from Figure 1 (b) is a perspective view of the internal unit removed from the housing, Figure 3 (b) is a perspective view showing a state where the outer cover is removed from the inner unit.

[0036] Figure 4 (a) The structure is viewed from the columnar portion side Figure 3 (a) is a perspective view of the holder of the internal unit shown, Figure 4 (b) is a perspective view of the retainer as viewed from the coupling portion side.

[0037] Figure 5 (a) Observe from another angle Figure 4 (b) is a perspective view of the joint shown, Figure 5 (b) Yes Figure 4 A cross-sectional perspective view of a broken retainer is shown.

[0038] Figure 6 (a) is the composition Figure 3 (a) is a perspective view of the outer shell of the inner unit shown, Figure 6 (b) is its front view.

[0039] Figure 7 yes Figure 3 (a) Front view of the internal unit shown.

[0040] Figure 8 (a) is the composition Figure 1 A front view of the cap of the one-way clutch is shown, Figure 8 (b) is a cross-sectional perspective view of the broken cap. DETAILED DESCRIPTION

[0041] Next, an embodiment of the one-way clutch according to the present invention will be described.

[0042] Figure 1 (a) is a front view of a one-way clutch 1 according to an embodiment of the present invention, Figure 1(b) is a cross-sectional perspective view of the one-way clutch 1 taken along line Ib-Ib. The one-way clutch 1 is constructed such that an inner unit 5 consisting of a retainer 3 and an outer sleeve 4 is housed in a housing 2, and a cap 6 is fitted into an insertion opening of the housing 2 of the inner unit 5. The one-way clutch 1 is inserted into the inner unit 5 and a shaft 7 (see FIG. Figure 7 ) is transmitted to the housing 2. The housing 2 has a rubber roller wound on its periphery, or a gear is formed on its periphery, and only the unidirectional rotation of the shaft 7 is transmitted to these rubber rollers or gears through the one-way clutch 1.

[0043] Figure 2 (a) shows a front view of the shell 2, and (b) shows a cross-sectional stereoscopic view taken along the IIb-IIb line. The shell 2 is formed into a hollow cylindrical shape by resin or metal, etc., and spaces with different inner diameters are formed inside the shell and arranged along the axial direction. The large space with the inner diameter for accommodating the internal unit 5 constitutes the storage portion 2a of the internal unit 5. The storage portion 2a has an inner diameter that covers the outer peripheries of the arrangement of the retainer 3 and the outer sleeve 4, covering the outer peripheries of the retainer 3 and the outer sleeve 4. On one end side of the storage portion 2a in the axial direction of the shell 2, the inner diameter of the shell 2 is reduced to form a limiting wall 2b. On the other end side of the storage portion 2a in the axial direction of the shell 2, on the insertion port 2c opening to the storage portion 2a of the internal unit 5, the fitting groove 2d for the cap 6 to be fitted is formed in a circular ring shape along its inner periphery. The stopper wall 2 b restricts movement of the internal unit 5 toward one end side (thrust direction) of the storage portion 2 a , and the cap 6 fitted into the insertion port 2 c restricts detachment of the internal unit 5 from the insertion port 2 c .

[0044] In addition, the housing 2 has an inner diameter portion 2e having an inner diameter smaller than the inner diameter of the receiving portion 2a on one side and the opposite side where the cap 6 of the receiving portion 2a is engaged. The inner diameter of the inner diameter portion 2e is formed to be smaller than the inner diameter of each space formed on both sides thereof, the inner diameter of which is smaller than the inner diameter of the receiving portion 2a. The shaft 7 of the housing 2 is coaxially inserted into the inner diameter portion 2e and is connected to the shaft 7 only in the inner diameter portion 2e. In addition, in the inner circumference of the housing 2, the engaging portion 2f that engages with the retainer 3 extends along its axial direction and is formed at three locations. In this embodiment, each engaging portion 2f extends from the limiting wall 2b to the insertion port 2c at a length L1 in the inner circumference of the receiving portion 2a.

[0045] Figure 3 (a) is a perspective view of the internal unit 5 taken out from the housing 2, Figure 3 (b) is a perspective view of the state in which the outer cover 4 is removed from the inner unit 5. Figure 4 (a) is a perspective view of the retainer 3 as viewed from the columnar portion 3a side. Figure 4 (b) is a perspective view of the retainer 3 viewed from the side of the coupling portion 3b. Figure 5 (a) is a perspective view of the joint 3b from another angle. Figure 5 (b) is a cross-sectional perspective view of the cage 3 broken along the axial direction.

[0046] The holder 3 is formed of resin or metal, etc. Figure 5 The shaft 7 is inserted into the inner diameter portion 3d formed by the central opening of the base 3c shown in (b). On the base 3c, a plurality of columnar portions 3a are uprightly provided at predetermined intervals in the circumferential direction surrounding the shaft 7 inserted into the inner diameter portion 3d. In addition, on the base 3c on one side and the opposite side of each upright columnar portion 3a, the engaged portion 3e and the coupling portion 3b provided at three locations are extended to form a cylindrical shape surrounding the inserted shaft 7. In this embodiment, the engaged portion 3e is provided at three locations through the coupling portion 3b in the axial direction of the shell 2, starting from the end face 3f of the coupling portion 3b with a predetermined length L2 (reference Figure 4 (a)) is formed due to lack of Figure 5 As shown in Figure (a), when viewing the retainer 3 from the side of the coupling portion 3b, the coupling portion 3b is circumferentially divided by the respective engaged portions 3e on the islands formed in a roughly C-shape, forming a buffer portion that cushions the stress applied to the coupling portion 3b. The engaging portions 2f engage with these engaged portions 3e in the axial direction of the retainer 3, transmitting the rotation of the retainer 3 to the housing 2.

[0047] In the retainer 3, when the engaged portion 3e and the engaging portion 2f are engaged with each other, the length L1 of each engaging portion 2f is set to be longer than the length L2 of the engaged portion 3e (L1 ≥ L2) so that a gap s is generated between the end face 3f of the coupling portion 3b and the limiting wall 2b (refer to Figure 1 (b)), and the end face 3f of the joint 3b is opposite to the limiting wall 2b. In addition, the end face 3g (reference Figure 4 (a) The length L3 of the protrusion is set to be longer than the predetermined length L2 of the engaged portion 3e (L3>L2). In addition, the length L3 of the connecting portion 3b protruding from the end surface 3g of the base 3c on which each columnar portion 3a is provided is set to be longer than the length L4 of each columnar portion 3a protruding from the end surface 3g (L3≥L4).

[0048] like Figure 6 (a) Stereoscopic image, Figure 6 As shown in the front view of (b), the outer sleeve 4 is a hollow cylindrical shape whose inner circumference surrounds the side of each columnar portion 3a provided upright in the base 3c of the retainer 3. The outer sleeve 4 is formed of resin or metal. As shown in the figure (b), the outer circumference of the outer sleeve 4 is a shape in which arc surfaces 4a and flat surfaces 4b are alternately arranged. In addition, a wedge surface 4c is formed on the inner circumference of the outer sleeve 4, and its radial position decreases in the clockwise direction in the figure. Figure 3As shown in FIG. 1 , the outer sleeve 4 is mounted on the retainer 3 around the sides of each columnar portion 3a of the retainer 3, and together with the retainer 3, forms an internal unit 5. In this embodiment, the retainer 3 is secured to the outer sleeve 4 by being press-fitted into the outer sleeve 4. The inner rectangular inner wall surface 4d of the outer sleeve 4, which is mounted in the retainer 3, abuts against the side of the raised portion 3h rising from the base 3c of each columnar portion 3a, where the corner post is formed.

[0049] The outer sleeve 4 surrounds the sides of the columnar portions 3a of the retainer 3. Figure 3 (a) and Figure 7 As shown, a pocket portion 5 a is formed on the inner unit 5 . Figure 7 This is a front view of the internal unit 5. The pocket portion 5a is formed between adjacent columnar portions 3a and 3a, and is sandwiched between the inner wall surface of the outer sleeve 4 and the outer periphery of the shaft 7 indicated by the dotted line in the figure. Figure 3 As shown in Figure 5(b), the pocket 5a houses a cylindrical steel needle roller 8 and a steel spring 9, which is generally S-shaped in side view. The needle roller 8 constitutes a rolling element capable of free rolling within the pocket 5a. The spring 9 constitutes an elastic member that urges the needle roller 8 toward the pocket 5a, located on one side of the columnar portion 3a of one of the adjacent columnar portions 3a, 3a. The elastic member can be integral with the retainer 3 and can be provided on the side of the columnar portion 3a of the pocket 5a facing the retainer 3, so as to be integrally formed with the retainer 3.

[0050] An inner unit 5 having a jacket 4 mounted on the holder 3 around each columnar portion 3a (see Figure 3 (a) Insert the holder 3 into the housing 2a inside the housing 2 from the insertion port 2c of the housing 2. Figure 1 As shown in (b), the outer periphery of the joint 3b is aligned with the outer periphery of the outer sleeve 4 and is coaxially arranged in the housing 2. Afterwards, the insertion port 2c of the housing 2 is covered by the cap 6, and the insertion port 2c is blocked. The front view of the cap 6 is shown in FIG. Figure 8 (a) A three-dimensional cross-sectional view of the fracture along line VIIIb-VIIIb is shown in Figure 8 (b) The cap 6 is a hollow cylindrical shape having an inner diameter portion 6a through which the shaft 7 is inserted. It is molded from resin or metal, and has a circumferentially protruding engagement ridge 6b formed on the outer circumference. When the insertion opening 2c is covered by the cap 6, the engagement ridge 6b engages with the engagement groove 2d formed in the insertion opening 2c of the housing 2, securing the cap 6 in the insertion opening 2c.

[0051] In the one-way clutch 1 constructed in this way, the rotation of the shaft 7 is transmitted to the housing 2 in accordance with the rolling position of the needle roller 8 in the pocket portion 5a. Figure 7When the shaft 7 rotates in the clockwise direction A, where the radial position of the wedge surface 4c shown decreases, the needle rollers 8, which are in contact with the outer periphery of the shaft 7, also roll in the same direction and engage between the wedge surface 4c and the outer periphery of the shaft 7. As a result, the needle rollers 8 are locked, transmitting torque from the shaft 7 to the housing 2. The clockwise rotation of the shaft 7 in the clockwise direction A is then transmitted to the housing 2, causing the housing 2 to also rotate in the same direction.

[0052] On the other hand, when shaft 7 rotates in the counterclockwise direction B, as the radial position of wedge surface 4c increases, needle roller 8, which is in contact with the outer circumference of shaft 7, also rolls in the same direction. Needle roller 8 enters a free state, unconstrained by wedge surface 4c and the outer circumference of shaft 7. Therefore, torque from shaft 7 to housing 2 is not transmitted, and the counterclockwise rotation of shaft 7 in the direction B is not transmitted to housing 2, preventing housing 2 from rotating. Consequently, the rotation of shaft 7 is transmitted only in the clockwise direction A, depending on the rotational position of needle roller 8 in pocket 5a.

[0053] In the one-way clutch 1 of this embodiment, the retainer 3 and outer sleeve 4 are housed in the housing portion 2a of the housing 2, which has an inner diameter covering the outer circumferences of the respective retainers. The rotation of the retainer 3 is transmitted to the housing 2 by the engagement portion 2f formed on the inner circumference of the housing 2, which engages with the engagement portion 3e provided on the coupling portion 3b in the axial direction of the housing 2. Therefore, unlike the one-way clutch disclosed in Patent Document 1, the inner circumference of the housing and the outer sleeve engage in the radial direction of the one-way clutch. Unlike conventional one-way clutches, which have limitations on reducing the radial thickness of the outer sleeve, this eliminates the need for ensuring a radially spaced engagement space between the engagement portion 2f and the engagement portion 3e in the one-way clutch 1, enabling the radial dimensions of the one-way clutch 1 to be reduced.

[0054] Furthermore, the internal unit 5 housed in the housing portion 2a of the housing 2 is restricted from moving toward one end of the housing portion 2a by a stopper wall 2b formed on one end of the housing portion 2a. Furthermore, by engaging a cap 6 with an insertion opening 2c at the other end of the housing portion 2a and opening toward the housing portion 2a of the internal unit 5, the internal unit 5 is restricted from disengaging from the insertion opening 2c. Therefore, to prevent the internal unit 5, through which the shaft 7 is inserted, from disengaging, the assembly work of inserting a pair of retaining rings into the shaft, as in the conventional one-way clutch disclosed in Patent Document 2, is no longer necessary, thereby reducing assembly effort.

[0055] Furthermore, according to the one-way clutch 1 of this embodiment, the engaging portion 3b is formed by having a predetermined length L2 cut out from the end surface 3f of the engaging portion 3b in the axial direction thereof at multiple locations, thereby forming the engaged portion 3e and constituting the aforementioned buffer portion. This allows the engaging portion 3b to be flexible in a direction intersecting the axial direction of the housing 2. Therefore, when bending stress or torsional stress is applied to the housing 2, the engaging portion 3b elastically deforms in response to these stresses, absorbing them. This prevents the needle roller 8 from tightening or slipping, thereby preventing improper engagement of the needle roller 8 during the locking operation of the one-way clutch 1 and improper rolling during the idling operation.

[0056] Furthermore, according to the one-way clutch 1 of this embodiment, the length L3 of the engaging portion 3b is longer than the length L2 of the engaged portion 3e (L3>L2). This maintains the component strength of the engaging portion 3b of the retainer 3. Consequently, the engaged portion 3e formed in the engaging portion 3b is securely engaged with the engaging portion 2f formed on the inner circumference of the housing 2, and the rotation of the retainer 3 is reliably transmitted to the housing 2. Furthermore, the retainer 3 can be reliably positioned relative to the housing 2.

[0057] Furthermore, according to the one-way clutch 1 of this embodiment, when the engaged portion 3e and the engaging portion 2f engage with each other, a gap s (L1 ≥ L2) is generated between the end face 3f of the coupling portion 3b and the limiting wall 2b. Therefore, when the engaged portion 3e and the engaging portion 2f engage, the end face 3f of the coupling portion 3b and the limiting wall 2b no longer abut against each other. Therefore, the abutment between the end face 3f of the coupling portion 3b and the limiting wall 2b prevents damage to the various components.

[0058] In addition, according to the one-way clutch 1 of this embodiment, the length L3 of the coupling portion 3b extending from the end face 3g is longer than the length L4 of each columnar portion 3a protruding from the end face 3g (L3≥L4), so that the rotation of the retainer 3 in the storage portion 2a is stable, and the rotation transmission from the retainer 3 to the housing 2 is smooth.

[0059] Furthermore, if there is play (looseness) between the fixed portions of retainer 3 and outer sleeve 4, the relative rotational position of retainer 3 and outer sleeve 4 may be misaligned due solely to this looseness, causing a change in the positional relationship between columnar portion 3a of retainer 3 and wedge surface 4c on the inner wall of outer sleeve 4. If this change in the positional relationship between columnar portion 3a and wedge surface 4c causes the needle roller 8 housed in pocket 5a to collide with columnar portion 3a before contacting wedge surface 4c when the unidirectional rotation of shaft 7 is transmitted to housing 2. In this case, needle roller 8 is obstructed by columnar portion 3a, preventing it from engaging and locking the wedge surface 4c with the outer circumference of shaft 7, and the unidirectional rotation of shaft 7 is no longer transmitted to housing 2.

[0060] However, according to the one-way clutch 1 of this embodiment, by ensuring that the periphery of the angular columnar raised portion 3h of each columnar portion 3a abuts the rectangular inner wall surface 4d of the outer housing 4, and thereby pressing the retainer 3 into the outer housing 4, no gap is created between the fixed portions of the retainer 3 and the outer housing 4, and no rotational positional misalignment between the retainer 3 and the outer housing 4 occurs. Consequently, the positional relationship between the columnar portion 3a and the wedge surface 4c remains unchanged at its original set position, and the locking action of the needle rollers 8 engaging the wedge surface 4c with the outer periphery of the shaft 7 is no longer hindered by the columnar portion 3a. Consequently, the unidirectional rotation of the shaft 7 can be reliably transmitted to the housing 2 through the locking action of the needle rollers 8 engaging the wedge surface 4c with the outer periphery of the shaft 7.

[0061] Furthermore, according to the one-way clutch 1 of this embodiment, the shaft 7 is supported for rotation by being inserted through the inner diameter portion 3d formed in the base 3c of the retainer 3, the inner diameter portions 2e provided in the housing 2 on one side and the opposite side of the cap 6 where the housing portion 2a is provided, and the inner diameter portion 6a provided in the cap 6. Therefore, the shaft 7 rotates stably without shaking.

[0062] Furthermore, according to the one-way clutch 1 of this embodiment, the outer circumferential surface of the outer sleeve 4 is formed in a shape in which arcuate surfaces 4a and flat surfaces 4b are alternately arranged. Therefore, the outer sleeve 4 can be easily positioned during automatic assembly of the one-way clutch 1.

[0063] In the above embodiment, the engaging portion 2f is formed to protrude axially toward the inner circumference of the housing portion 2a, while the engaged portion 3e is formed to be recessed axially toward the coupling portion 3b. This describes the embodiment in which the engaging portion 2f and the engaged portion 3e engage. However, conversely, the engaging portion 2f may be formed to be recessed axially along the inner circumference of the housing 2, which is located within the reduced diameter of the housing 2, while the engaged portion 3e may be formed to extend axially from the end face 3f of the coupling portion 3b, with the engaging portion 2f and the engaged portion 3e engaging axially along the housing 2. This configuration also achieves the same functional effects as the above embodiment.

[0064] In addition, if Figure 5 In the example shown in (a), the buffer portion formed by the connecting portion 3b is formed by splitting the connecting portion 3b into C-shaped islands. However, a cylindrical connecting portion 3b can also be configured to be split only in the circumferential direction by the connected portion 3e, with arcuate walls standing upright on the base 3c at predetermined intervals. With this configuration, stress applied to the housing 2 is absorbed by the buffer portion, achieving the same functional effects as the above embodiment.

[0065] Furthermore, although the outer peripheral surface of the outer sleeve 4 is described as having an alternately arranged shape of arcuate surfaces 4 a and flat surfaces 4 b , it may also be simply cylindrical.

[0066] Description of Reference Signs

[0067] 1 One-way clutch, 2 Housing, 2a Receiving portion, 2b Limiting wall, 2c Insertion port, 2d Fitting groove, 2e Inner diameter portion of housing 2, 2f Engaging portion, 3 Retainer, 3a Columnar portion, 3b Joint, 3c Base, 3d Inner diameter portion of retainer 3, 3e Engaged portion, 3f End face of joint 3b, 3g End face of base 3c, 3h Rising portion, 4 Outer sleeve, 4a Arc surface, 4b Flat surface, 4c Wedge surface, 4d Rectangular inner wall surface, 5 Internal unit, 5a Pocket portion, 6 Cap, 6a Inner diameter portion of cap 6, 6b Fitting ridge, 7 Shaft, 8 Needle roller (rolling element), 9 Spring (elastic component).

Claims

1. A one-way clutch, characterized in that: It is composed of the following: A retainer having a plurality of columnar portions standing upright at predetermined intervals on the base in a circumferential direction around an axis inserted through an inner diameter portion formed on the base; a hollow cylindrical outer sleeve, the inner circumference of which surrounds the side portions of each of the columnar portions erected on the base; a cylindrical rolling element rollably held in a pocket portion, wherein the pocket portion is formed between adjacent columnar portions and is sandwiched between the inner wall surface of the outer sleeve and the outer periphery of the shaft; an elastic member that applies force to the rolling element on the columnar portion side of one of the adjacent columnar portions in the pocket portion; a housing covering the outer periphery of the retainer and the outer casing and transmitting the unidirectional rotation of the shaft according to the rolling position of the rolling element in the pocket portion; The retainer is provided with a coupling portion of a clamped portion on one side and an opposite side of each columnar portion, and is extended to form a cylindrical shape around the axis. The outer periphery of the coupling portion is arranged on the outer periphery of the outer sleeve and is coaxially arranged with the outer sleeve in the housing. The shell has a receiving portion covering the inner diameter of each outer periphery of the arrangement of the retainer and the outer sleeve, and an engaging portion is formed on the inner periphery. The engaging portion engages with the engaged portion in the axial direction and transmits the rotation of the retainer to the shell. A limiting wall is formed on one end side of the receiving portion opposite to the end face of the coupling portion. The limiting wall limits the movement of the retainer and the outer sleeve toward one end side of the receiving portion in the axial direction. The cap is engaged with the insertion port and limits the separation of the retainer and the outer sleeve from the insertion port. The insertion port is on the other end side of the receiving portion in the axial direction and is open to the receiving portion of the retainer and the outer sleeve.

2. The one-way clutch according to claim 1, characterized in that: The engaged portion of the coupling portion of the retainer is formed by being cut out by a predetermined length in the axial direction from an end surface of the coupling portion at a plurality of locations.

3. The one-way clutch according to claim 2, characterized in that: The retainer is set so that the length of the coupling portion extending from the end surface of the base on which the columnar portion is erected is longer than a predetermined length of the engaged portion.

4. The one-way clutch according to claim 1, characterized in that: The lengths of the engaged portion and the engaging portion are set such that when they are engaged with each other, a gap is generated between the end surface of the combining portion and the limiting wall.

5. The one-way clutch according to claim 2, characterized in that: The lengths of the engaged portion and the engaging portion are set such that when they are engaged with each other, a gap is generated between the end surface of the combining portion and the limiting wall.

6. The one-way clutch according to claim 3, characterized in that: The lengths of the engaged portion and the engaging portion are set such that when they are engaged with each other, a gap is generated between the end surface of the combining portion and the limiting wall.

7. The one-way clutch according to any one of claims 1 to 6, characterized in that: The retainer is fixed to the outer shell by being press-fitted into the outer shell so that the rectangular inner wall surface of the outer shell abuts against the periphery of the side portion of each of the columnar portions having a prism shape in the rising portion from the base.

8. The one-way clutch according to any one of claims 1 to 6, characterized in that: The cap has an inner diameter portion for inserting the shaft. The housing includes inner diameter portions for inserting the shaft on one side of the housing portion where the cap is fitted and on the opposite side.

9. The one-way clutch according to any one of claims 1 to 6, characterized in that: The outer peripheral surface of the outer sleeve is formed into a shape in which arc surfaces and flat surfaces are alternately arranged.

10. The one-way clutch according to claim 8, characterized in that: The outer peripheral surface of the outer sleeve is formed into a shape in which arc surfaces and flat surfaces are alternately arranged.

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