Wedge block type one-way clutch and electric power-assisted bicycle

Abstract

The utility model discloses a wedge block type one-way clutch and an electric power-assisted bicycle, and relates to the field of bicycles. The wedge-type one-way clutch includes: an inner core having a first circular orbit; the outer ring body surrounds the inner core body at intervals and is provided with a second circular track, and a circular-ring-shaped retaining cavity is formed between the outer ring body and the second circular track; the one-way transmission set is arranged in the retaining cavity, the two circumferential ends of the one-way transmission set are a first end and a second end respectively, the one-way transmission set comprises at least two wedge blocks which are sequentially and tightly arranged in the circumferential direction, and each wedge block is provided with an anti-rotation protrusion protruding towards the second end in the circumferential direction so as to be pressed on the adjacent wedge block or the adjacent one-way transmission set; the elastic loading assembly is arranged at the first end of the one-way transmission set and connected with the adjacent wedge blocks so as to press the wedge blocks towards the second end. According to the wedge block type one-way clutch, the overall axial size can be reduced, and the bearing capacity is improved. Assembly is relatively easy, and failure is not prone to occurring.

Description

Technical Field

[0001] The utility model relates to the field of bicycles, in particular to a wedge-type one-way clutch and an electric power-assisted bicycle. Background Art

[0002] One-way clutches are widely used in mid-mounted motors, hub motors and other structures. Their main function is to ensure that the motor power and human power are output without affecting each other.

[0003] As the name implies, a one-way clutch can only rotate in one direction and is driven when a force is applied in the other direction. The reliability and performance of a one-way clutch are critical, and the structure and force requirements of the components are strict. A good clutch is durable and can achieve small size and high torque output.

[0004] Commonly used one-way clutches include roller type and wedge type. Generally, roller type is easy to process but its load-bearing capacity is not as good as that of wedge type. Wedge type has complex process, usually requires ball bearing support on both sides, and has a longer axial dimension. If it is to be used in a small space, it is difficult to choose a suitable wedge type one-way clutch.

[0005] In the prior art, there has been a one-way clutch with an outer rotor fully loaded with wedges, which is difficult to assemble and easy to fail. Therefore, how to improve the wedge-type one-way clutch is one of the research and development directions. Utility Model Content

[0006] The utility model aims to solve at least one of the technical problems existing in the prior art. To this end, the utility model proposes a wedge-type one-way clutch, which can effectively control its size while ensuring the load-bearing capacity and is easy to assemble.

[0007] The utility model also provides an electric power-assisted bicycle with the wedge-type one-way clutch.

[0008] According to the wedge-type one-way clutch of the embodiment of the utility model, it includes: an inner core body, the outer circumferential surface of the inner core body has a first circular track; an outer ring body, the outer ring body is arranged around the inner core body at intervals, the inner circumferential surface of the outer ring body has a second circular track concentric with the first circular track, and a circular retaining cavity is formed between the inner circumferential surface of the outer ring body and the outer circumferential surface of the inner core body; at least one one-way transmission group, the one-way transmission group is arranged in the retaining cavity and has a first end and a second end at two circumferential ends respectively, the one-way transmission group includes at least two wedge blocks arranged closely in sequence along the circumferential direction, each of the wedge blocks is provided with an anti-rotation protrusion protruding along the circumferential direction toward the second end to press on the adjacent wedge block or the adjacent one-way transmission group; an elastic loading component, the elastic loading component is located in the retaining cavity, the elastic loading component is arranged at the first end of the one-way transmission group and connects the adjacent wedge blocks to press the wedge blocks toward the second end.

[0009] According to the wedge-type one-way clutch of the embodiment of the utility model, the axial space size can be saved to a certain extent, and the wedge blocks can be arranged more densely in the circumferential direction, which is conducive to reducing the overall axial size and improving the load-bearing capacity. Among them, the wedge blocks are blocked by the anti-rotation protrusion on one side and pressed by the elastic loading component on the other side. The wedge blocks are pre-tightened and are not easy to rotate excessively and get stuck, which ensures the tight arrangement of the wedge blocks and the reliability of the one-way transmission of the wedge-type one-way clutch. The elastic loading components are not only small in number but also do not need to occupy too much axial space, so they are relatively easy to assemble and not prone to failure.

[0010] In some embodiments, the elastic loading assembly includes: an elastic member, which is extended along a tangential direction of the first end and can be elastically deformed in the tangential direction of the first end.

[0011] Specifically, the elastic loading assembly further includes: a top sleeve sleeved on at least one end of the elastic member.

[0012] In some embodiments, each of the one-way transmission groups further includes: a centering column disposed at the first end, the axis of the centering column being at a fixed distance from the axis of the inner core, and the elastic loading assembly being connected between the centering column and the adjacent wedge block.

[0013] Specifically, a positioning hole is provided on at least one of the centering column and the adjacent wedge block, and at least one end of the elastic loading component is located in the positioning hole.

[0014] Furthermore, the centering column is a rotating body, and the diameter of the centering column is equal to the difference between the radius of the second circular orbit and the radius of the first circular orbit.

[0015] Optionally, there are at least three one-way transmission groups, and there are at least three corresponding centering columns. A positioning shaft is provided at the center of each centering column, and one of the following modes is satisfied:

[0016] Method 1: All the positioning shafts are connected to the inner core;

[0017] Mode 2: All the positioning shafts are connected to the outer ring body;

[0018] Mode three: the wedge-type one-way clutch also includes a side frame, and all the positioning shafts are connected to the side frame.

[0019] In some embodiments, the wedge has a circumferential contour;

[0020] The circumferential contour line includes an outer ring working point and an inner ring working point, a line connecting the outer ring working point to the inner ring working point is a working line, a length of the working line is equal to a difference between a radius of the second circular track and a radius of the first circular track, and when the outer ring working point contacts the first circular track, the inner ring working point contacts the second circular track;

[0021] The anti-rotation protrusion is located on one side of the working line in the circumferential direction toward the second end;

[0022] The midpoint of the working line is the center point of the circumferential contour line, and the line segment passing through the center point and intersecting with the circumferential contour line is the center line;

[0023] The length of the through-center line between the anti-rotation protrusion and the inner ring working point at one end is greater than the length of the working connection line;

[0024] The circumferential contour line has a symmetrical portion, and the central angle from the symmetrical portion to the inner ring working point and the central angle from the anti-rotation protrusion to the inner ring working point are equal. The length of the center line between one end of the symmetrical portion and the inner ring working point is shorter than the length of the working line.

[0025] In some specific embodiments, the center of gravity of the wedge block is located on a side of the working line that is circumferentially directed toward the second end.

[0026] Specifically, a weight-reducing hole is provided on the wedge block, and the weight-reducing hole is located on a side of the working line facing the first end in the circumferential direction.

[0027] In some specific embodiments, the circumferential contour line includes:

[0028] A first arc segment, the inner ring working point is located on the first arc segment, and the radius of the first arc segment is greater than half the length of the working line;

[0029] A second arc segment, the outer ring working point is located on the second arc segment, and the radius of the second arc segment is greater than half the length of the working line;

[0030] A third arc segment, one end of the third arc segment is connected to the first arc segment, the curvature of the third arc segment is greater than the curvature of the first arc segment, the third arc segment constitutes the contour line of the anti-rotation protrusion, and the distance from the center point to any point on the third arc segment is greater than half the length of the working line.

[0031] In some specific embodiments, at least two of the wedge blocks in the same one-way transmission group are first wedge blocks, and the circumferential contour line of the first wedge block further includes:

[0032] a fourth arc segment, the fourth arc segment being located on a side of the working line away from the third arc segment, the fourth arc segment being connected between the first arc segment and the second arc segment, and the radius of the fourth arc segment being equal to half the length of the working line;

[0033] When two adjacent wedge blocks are pressed tightly, the third arc segment of the wedge block adjacent to the first end contacts the fourth arc segment of the wedge block adjacent to the second end.

[0034] In some specific embodiments, the wedge block located at the first end in at least one of the one-way transmission groups is a second wedge block, and the circumferential contour line of the second wedge block further includes:

[0035] A first straight line segment, the first straight line segment is located on a side of the working line away from the third arc segment, and the first straight line segment is connected between the first arc segment and the second arc segment;

[0036] One end of the elastic loading component abuts against the first straight section of the second wedge block.

[0037] The electric power-assisted bicycle according to an embodiment of the utility model comprises: a motor; an output shaft; and a wedge-type one-way clutch according to the above embodiment of the utility model, wherein one of the inner core body and the outer ring body is connected to the motor, and the other is connected to the output shaft.

[0038] Additional aspects and advantages of the present invention will be given in part in the following description, and in part will become apparent from the following description, or will be learned through the practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 is a schematic diagram of a wedge-type one-way clutch according to an embodiment of the utility model;

[0040] Figure 2 yes Figure 1 A partial enlarged view of

[0041] Figure 3 is a schematic diagram of a first wedge according to an embodiment of the utility model;

[0042] Figure 4 yes Figure 3 Force analysis diagram of the first wedge shown;

[0043] Figure 5 is a schematic diagram of a second wedge according to an embodiment of the utility model;

[0044] Figure 6 It is a schematic diagram of a wedge-type one-way clutch according to another embodiment of the utility model.

[0045] Reference numerals:

[0046] Wedge-type one-way clutch 10;

[0047] Inner core 1, first circular track 11;

[0048] Outer ring body 3, second circular track 31;

[0049] Holding cavity 4;

[0050] One-way transmission group 5, first end 5A, second end 5B;

[0051] Wedge block 51, anti-rotation protrusion 511, symmetrical portion 512, weight-reducing hole 513;

[0052] A first wedge block 51X and a second wedge block 51Y;

[0053] A first arc segment 501, a second arc segment 502, a third arc segment 503, a fourth arc segment 504, and a first straight line segment 508;

[0054] Outer ring working point P2, inner ring working point P1, center point O1, center of gravity G1;

[0055] Working connection line D1, passing center line E1;

[0056] Centering column 53;

[0057] Positioning shaft 54;

[0058] Elastic loading assembly 7, elastic member 71, top sleeve 72, through hole 721, positioning hole 73. DETAILED DESCRIPTION

[0059] The embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and should not be construed as limiting the present invention.

[0060] The disclosure below provides many different embodiments or examples for realizing different structures of the utility model. In order to simplify the disclosure of the utility model, the components and settings of specific examples are described below. Of course, they are merely examples, and the purpose is not to limit the utility model. In addition, the utility model can repeat reference numbers and / or letters in different examples. This repetition is for the purpose of simplification and clarity, and does not itself indicate the relationship between the various embodiments and / or settings discussed. In addition, the utility model provides various specific examples of processes and materials, but those of ordinary skill in the art can be aware of the applicability of other processes and / or the use of other materials.

[0061] The sprag-type one-way clutch 10 according to an embodiment of the present invention will be described below with reference to the accompanying drawings.

[0062] According to the wedge-type one-way clutch 10 of the utility model embodiment, Figure 1 and Figure 2 As shown, it includes: an inner core body 1, an outer ring body 3, at least one one-way transmission group 5 and an elastic loading component 7.

[0063] The outer circumference of the inner core 1 has a first circular track 11 . The shape of the inner core 1 is not limited, and can be a ring, a cylinder, or other shapes, as long as its outer circumference can form the first circular track 11 .

[0064] The outer ring body 3 is disposed around the inner core body 1 at intervals, and the inner circumference of the outer ring body 3 has a second circular track 31 concentric with the first circular track 11. The shape of the outer ring body 3 is not limited, and can be a circular ring or a square tube or other shapes.

[0065] A circular retaining cavity 4 is formed between the inner circumference of the outer ring body 3 and the outer circumference of the inner core body 1. Here, the center of the first circular track 11 and the center of the second circular track 31 are both on the axis of the retaining cavity 4. The shape of the cross section of the retaining cavity 4 through the axis is not limited, and can be two symmetrical rectangular cavities, two symmetrical drum-shaped cavities, or two symmetrical cavities of other shapes.

[0066] The one-way transmission group 5 is arranged in the retaining cavity 4 and has two circumferential ends, namely a first end 5A and a second end 5B. The one-way transmission group 5 is distributed along the circumference of the retaining cavity 4. Here, there can be one or more one-way transmission groups 5 in the retaining cavity 4. When there is only one one-way transmission group 5 in the retaining cavity 4, the first end 5A and the second end 5B of the one-way transmission group 5 can be connected to form a full circle ring. The transmission structure in the retaining cavity 4 can be all one-way transmission groups 5, or part of it can be the one-way transmission assembly 5 of the present application and part of it can be other one-way transmission structures known in the art, that is, a combination of at least two one-way transmission structures is formed. For other types of one-way transmission structures known in the art, their structures are not repeated here.

[0067] Compared with the one-way bearing in the prior art, the wedge-type one-way clutch 10 of the present application can avoid occupying too much axial space and circumferential space and arrange the wedges 51 more densely.

[0068] Specifically, in the prior art roller-type one-way bearing, a retaining frame is arranged between the outer ring and the inner ring. The retaining frame includes a retaining block located between every two adjacent rollers. A wedge-shaped space is formed on the retaining block. A spring is also arranged between every two retaining blocks. The spring squeezes the roller into the wedge-shaped space to achieve a pre-tightening effect. When the inner ring rotates in one direction relative to the outer ring, the roller is driven to further squeeze toward the wedge-shaped space to clamp the inner ring and the outer ring, thereby realizing transmission. When the inner ring rotates in another direction relative to the outer ring, the roller is driven to move outside the wedge-shaped space and compress the spring, and the inner ring and the outer ring can rotate freely and cannot transmit. In this solution, the spring and retaining block between every two rollers occupy a large amount of circumferential space, the number of rollers in the retaining cavity is small, and the bearing capacity is weak.

[0069] In the prior art wedge-type one-way bearings, a retainer is usually required, and the retainer includes a retaining block located between each two adjacent wedges, which squeezes the circumferential space of the wedges. Even if the wedges in the retaining cavity of some wedge-type one-way bearings can be fully loaded, that is, the wedges are adjacent to each other to form a complete ring, an elastic member needs to be arranged between each two adjacent wedges to maintain preload. In this case, the installation position of the elastic member is limited, the number of elastic members is large, and the assembly difficulty is high.

[0070] If the wedge blocks in the holding cavity are fully loaded, an elastic member is set on one axial side of the wedge block, and the elastic member cooperates with all the wedge blocks to maintain pre-tightening. Then how to install this elastic member on the side of the wedge block and ensure that it cooperates with all the wedge blocks is also a problem. In this case, a retaining frame needs to be set on the side, and then space is provided for the elastic member. In particular, the elastic member is elastic, and how to install the elastic member on the retaining frame and ensure that it cooperates with all the wedge blocks is also a problem. At this time, the retaining frame cannot be made too small, otherwise the elastic member will easily get stuck on the side.

[0071] In order to solve the above-mentioned problem of one-way bearing, the present application proposes a wedge-type one-way clutch 10. Figure 2 The one-way transmission group 5 includes at least two wedges 51 closely arranged in sequence along the circumferential direction, and each wedge 51 is provided with an anti-rotation protrusion 511 protruding toward the second end 5B along the circumferential direction to press on the adjacent wedge 51 or the adjacent one-way transmission group 5. The elastic loading component 7 is located in the retaining cavity 4, and the elastic loading component 7 is provided at the first end 5A of the one-way transmission group 5 and connected to the wedge 51 at the first end 5A to press the wedge 51 toward the second end 5B.

[0072] That is to say, at least two wedge blocks 51 on the one-way transmission group 5 are closely arranged along the circumferential direction, that is, the wedge blocks 51 are adjacent to each other along the circumferential direction, and there is no need to leave circumferential space between two adjacent wedge blocks 51 of the same one-way transmission group 5 for retaining blocks and elastic parts. This is conducive to increasing the number of wedge blocks 51 and enhancing the load-bearing capacity.

[0073] By setting the elastic loading assembly 7 at the first end 5A, on the one hand, the elastic loading assembly 7 is located in the retaining cavity 4, and although it occupies a certain circumferential space, the elastic loading assembly 7 does not need to occupy the axial side space. One elastic loading assembly 7 is set for one one-way transmission group 5, and the number of elastic loading assemblies 7 is greatly reduced, and the circumferential space occupied is also limited. Therefore, the volume size occupied by the wedge-type one-way clutch 10 can still be reduced, the distribution density of the wedge 51 in the circumferential direction is increased, and the load-bearing capacity is increased. On the other hand, the elastic loading assembly 7 is constrained and limited by the wedge 51 in the circumferential direction, and the difficulty of assembly is greatly reduced.

[0074] By providing an anti-rotation protrusion 511 protruding toward the second end 5B along the circumferential direction on each wedge block 51, the wedge block 51 is pressed on the adjacent wedge block 51 or the adjacent one-way transmission group 5 by the anti-rotation protrusion 511, and the compression of the elastic loading component 7 is cooperated to achieve a close arrangement of all wedge blocks 51, and the wedge block 51 is pre-tightened and limited, and the wedge block 51 will not turn over and cause the possibility of getting stuck. In other words, when there is no input power, the wedge block 51 will not turn over to the second end 5B due to the obstruction of the anti-rotation protrusion 511, and the wedge block 51 will not turn over to the first end 5A due to the elastic pressure of the elastic loading component 7. In this way, the reliability of the one-way transmission of the wedge-type one-way clutch 10 can be achieved.

[0075] Moreover, in the wedge-type one-way clutch 10 of the present application, the pre-tightening of the wedge 51 on the one-way transmission group 5 relies on the blocking and spring pressure on both sides of the circumference. When the power is transmitted from the inner core body 1 to the outer ring body 3, one-way transmission can be achieved, and when the power is transmitted from the outer ring body 3 to the inner core body 1, one-way transmission can also be achieved. The application range is wider.

[0076] According to the wedge-type one-way clutch 10 of the embodiment of the utility model, the axial space size can be saved to a certain extent, and the wedge blocks 51 can be arranged more densely in the circumferential direction, which is conducive to reducing the overall axial size and improving the load-bearing capacity. Among them, the wedge blocks 51 are blocked on one side by the anti-rotation protrusion 511 and pressed by the elastic loading component 7 on the other side. The wedge blocks 51 are pre-tightened and are not easy to rotate excessively and get stuck, which ensures the tight arrangement of the wedge blocks 51 and the reliability of the one-way transmission of the wedge-type one-way clutch 10. The elastic loading components 7 are not only small in number but also do not need to occupy too much axial space, so they are relatively easy to assemble and not easy to fail.

[0077] In some embodiments, Figure 2 As shown, the elastic loading assembly 7 includes an elastic member 71, which is extended along the tangential direction of the first end 5A and can be elastically deformed in the tangential direction of the first end 5A. In other words, the elastic member 71 is in a long strip shape and is extended along the tangential direction of the first end 5A. Here, the axis of the elastic member 71 can be parallel to the tangential direction of the first end 5A, or can form a certain angle.

[0078] The elastic member 71 is arranged in this way, so that it has a large elastic expansion and contraction amount in the circumferential direction of the holding cavity 4, thereby having a strong ability to resist impact. In addition, the two ends of the elastic member 71 are squeezed and limited by the wedge blocks 51 on both sides, and the elastic member 71 is easy to assemble.

[0079] Specifically, the elastic member 71 may be a cylindrical spring. The elastic member 71 may also be other parts with greater elastic rigidity, such as an elastic disc, etc., which is not limited here.

[0080] Furthermore, if Figure 2 As shown, the elastic loading assembly 7 further includes: a top sleeve 72 sleeved on at least one end of the elastic member 71. In this way, the restriction of the top sleeve 72 can be obtained, the assembly reliability is further improved, and the probability of failure of the sprag-type one-way clutch 10 caused by the elastic member 71 falling off is reduced.

[0081] Optionally, top sleeves 72 may be provided at both ends of the elastic member 71 , and during assembly, the two top sleeves 72 are pressed together for easier operation.

[0082] Further optionally, a through hole 721 may be provided on the end surface of the top sleeve 72 to facilitate exhaust.

[0083] In some specific embodiments, when setting the top sleeve 72, the top sleeve 72 can be processed into an end face that matches the shape of the part to be connected (such as the wedge block 51, or the centering column 53 described later). For example, the end face can be made into an arc surface to fit closely against the centering column 53, thereby improving the positioning and limiting effect of the elastic loading component 7 and reducing the risk of falling off.

[0084] In some embodiments, Figure 1 and Figure 2 As shown, each one-way transmission group 5 further includes: a centering column 53 provided at the first end 5A, and the axis of the centering column 53 is at a fixed distance from the axis of the inner core 1.

[0085] The centering column 53 is provided to maintain the concentric arrangement of the first circular track 11 and the second circular track 31, so as to avoid the possibility that the first circular track 11 and the second circular track 31 are relatively skewed, resulting in a section of the holding cavity 4 being too narrow and a section of the holding cavity 4 being too wide. The centering column 53 can realize the centering support of the inner core body 1 and the outer ring body 3.

[0086] Specifically, the number of the centering posts 53 on the sprag-type one-way clutch 10 may be a multiple of 2 or a multiple of 3, but not less than 3.

[0087] Optionally, the centering column 53 is a cylinder, and of course it is not excluded that the centering column 53 is other rotating column.

[0088] In some specific embodiments, Figure 2 As shown, the elastic loading assembly 7 is connected between the centering column 53 and the adjacent wedge block 51. This does not affect the close arrangement of the adjacent wedge blocks 51, and the centering column 53 can be used to position the elastic loading assembly 7, reducing the difficulty of processing the wedge block 51.

[0089] Of course, the present application does not exclude the possibility that in some solutions, the elastic loading component 7 is connected between two adjacent wedge blocks 51 .

[0090] Specifically, Figure 2 As shown, at least one of the centering column 53 and the adjacent wedge block 51 is provided with a positioning hole 73, and at least one end of the elastic loading component 7 is located in the positioning hole 73. This further improves the positioning reliability of the elastic loading component 7, facilitates assembly, and reduces the probability of failure.

[0091] Optionally, the end of the positioning hole 73 is a tapered hole for easy processing.

[0092] In some specific examples of this application, such as Figure 2 As shown, a positioning hole 73 is provided on the wedge block 51, but no positioning hole 73 is provided on the adjacent centering column 53. Thus, after the elastic loading component 7 is assembled, the elastic loading component 7 limits the rotation of the wedge block 51 but does not limit the rotation of the centering column 53. The centering column 53 can roll automatically to reduce friction.

[0093] In some other specific examples of this application, such as Figure 6 As shown, a positioning hole 73 is provided on the centering column 53 , and no positioning hole 73 is provided on the adjacent wedge block 51 , so that after the elastic loading assembly 7 is assembled, the elastic loading assembly 7 limits the rotation of the centering column 53 .

[0094] Further, when the elastic loading assembly 7 includes the elastic member 71 and the top sleeve 72, one end of the elastic member 71 is located in the positioning hole 73 for limiting, and the other end of the elastic member 71 is sleeved with the top sleeve 72, and the top sleeve 72 is pressed against the wedge block 51 or the centering column 53. Furthermore, the top sleeve 72 is long enough in the length direction of the elastic member 71, and one end of the top sleeve 72 extends into the positioning hole 73, but does not press against the end of the positioning hole 73.

[0095] In some specific embodiments, Figure 2 As shown, the centering column 53 is a rotating body, and the diameter d1 of the centering column 53 is equal to the difference between the radius Rinside of the second circular track 31 and the radius Routside of the first circular track 11, that is, d1 = Rinside - Routside. In this way, a positioning column 53 can limit the inner core body 1 and the outer ring body 3, and can also roll to achieve the effect of reducing the friction force.

[0096] In some specific embodiments, there are at least three one-way transmission groups 5, and correspondingly at least three centering columns 53. A positioning shaft 54 ​​is disposed at the center of each centering column 53, and the positioning shaft 54 ​​can be supported.

[0097] For example, all positioning shafts 54 may be connected to the inner core 1 , so that the position of the centering column 53 relative to the inner core 1 is fixed.

[0098] For another example, all the positioning shafts 54 may be connected to the outer ring body 3 , so that the position of the centering column 53 relative to the outer ring body 3 is fixed.

[0099] For example, a side frame (not shown) can be provided, and all positioning shafts 54 are connected to the side frame. In this way, the centering column 53 is equivalent to being suspended, and the relative positions of all centering columns 53 are fixed.

[0100] Providing a positioning shaft 54 ​​on the centering column 53 and providing certain support and fixation is beneficial to maintaining the circumferential space between two adjacent centering columns 53 fixed. In this way, each unidirectional transmission group 5 has sufficient circumferential space size to avoid the possibility of over-crowding or over-length, further improving reliability and reducing the chance of jamming.

[0101] When the side frame is provided, the side frame can be provided in a circular ring shape, and the side frame can also be provided in the retaining cavity 4 and located on one axial side of the wedge block 51, so that the space occupied is small. As for the retaining frame in the prior art, the side frame of the present application only needs to limit the centering column 53, the structural size of the side frame does not need to be too large, and the occupied space can be controlled.

[0102] In some embodiments, Figure 2 and Figure 3 As shown, the wedge 51 has a circumferential contour.

[0103] like Figure 3As shown, the circumferential contour line includes an outer ring working point P2 and an inner ring working point P1, and the line connecting the outer ring working point P2 to the inner ring working point P1 is a working line D1. The length of the working line D1 is equal to the difference between the radius Rinside of the second circular track 31 and the radius Routside of the first circular track 11, that is, the length of the working line D1 = Rinside-Routside. When the outer ring working point P2 contacts the first circular track 11, the inner ring working point P1 contacts the second circular track 31.

[0104] The anti-rotation protrusion 511 is located on the side of the working line D1 facing the second end 5B in the circumferential direction. At this time, the wedge block 51 is subjected to elastic squeezing force from one side of the first end 5A.

[0105] like Figure 3 As shown, the midpoint of the working line D1 is the center point O1 of the circumferential contour line, and the line segment passing through the center point O1 and intersecting the circumferential contour line is the center line E1.

[0106] At this time, the length of the center line E1 between one end of the anti-rotation protrusion 511 and the inner ring working point P1 is greater than the length of the working line D1.

[0107] A symmetrical portion 512 is provided on the circumferential contour line, and the central angle α2 from the symmetrical portion 512 to the inner ring working point P1 and the central angle α1 from the anti-rotation protrusion 511 to the inner ring working point P1 are equal, and one end is at the center line E1 between the symmetrical portion 512 and the inner ring working point P1, and its length is less than the length of the working line D1. It should be noted here that the symmetrical portion 512 is not a specific structure, but a certain ray position. Relative to the center point O1, the central angle from the symmetrical portion 512 to the inner ring working point P1 is α1, and the central angle from the symmetrical portion 512 to the inner ring working point P1 is α2, and α1=α2.

[0108] Among the cross-center lines E1 on both sides of the working line D1, the cross-center line E1 with one end on the anti-rotation protrusion 511 side has a length greater than the length of the working line D1. The cross-center line E1 with one end on the symmetrical portion 512 side has a length less than the length of the working line D1.

[0109] So refer to Figure 4When the inner core 1 rotates relative to the outer ring body 3, the wedge block 51 generates a counterclockwise force around the center point O1, and the length of the center line E1 in contact with the first circular track 11 or the second circular track 31 is less than the length of the working line D1, so that both ends cannot contact the first circular track 11 or the second circular track 31. In this way, the inner core 1 can rotate freely relative to the outer ring body 3. On the contrary, when the inner core 1 rotates relative to the outer ring body 3, the wedge block 51 generates a clockwise force around the center point O1, and the length of the center line E1 in contact with the first circular track 11 or the second circular track 31 is greater than the length of the working line D1, and the two ends of the center line E1 are stuck on the first circular track 11 or the second circular track 31. In this way, the wedge block 51 wedges the inner core 1 and the outer ring body 3, and the two rotate synchronously. Thereby, the one-way transmission of the wedge-type one-way clutch 10 is realized, and the transmission direction can be transmitted from the inner core body 1 to the outer ring body 3, and can also be transmitted from the outer ring body 3 to the inner core body 1.

[0110] In some specific embodiments, Figure 2 and Figure 3 As shown, the center of gravity G1 of the wedge block 51 is located on the side of the working line D1 in the circumferential direction toward the second end 5B. This is conducive to utilizing the gravity inertia to make the anti-rotation protrusion 511 of the wedge block 51 press against the adjacent wedge block 51.

[0111] Specifically, the wedge block 51 is provided with a weight-reducing hole 513, which is located on the side of the working line D1 in the circumferential direction toward the first end 5A. The setting of the weight-reducing hole 513 can reduce the overall weight load on the one hand, and can offset the center of gravity G1 relative to the working line D1 on the other hand.

[0112] In some specific embodiments, Figure 3 and Figure 5 As shown, the circumferential contour line of the wedge block 51 includes: a first circular arc segment 501 , a second circular arc segment 502 , and a third circular arc segment 503 .

[0113] For the convenience of description, half the length of the working line D1 is called r0, that is, r0 = (Rinside - Routside) / 2.

[0114] like Figure 3 As shown, the inner ring working point P1 is located on the first arc segment 501 , and the radius r1 of the first arc segment 501 is greater than half the length of the working line D1 , that is, the radius r1 of the first arc segment 501 > r0 .

[0115] The outer ring working point P2 is located on the second arc segment 502 , and the radius r2 of the second arc segment 502 is greater than half the length of the working line D1 , that is, the radius r2 of the second arc segment 502 > r0 .

[0116] One end of the third arc segment 503 is connected to the first arc segment 501 , the curvature of the third arc segment 503 is greater than that of the first arc segment 501 , and the third arc segment 503 forms the contour of the anti-rotation protrusion 511 . That is, the radius r3 of the third arc segment 503 is less than the radius r1 of the first arc segment 501 .

[0117] The purpose of such a configuration is that the contact surfaces of the wedge block 51 and the first circular track 11 and the second circular track 31 are all arc surfaces with larger diameters, which increases the contact surface area and improves the load-bearing capacity, and does not affect the rotation state of the wedge block 51 during transmission, so that the wedge block 51 can adjust its position in time according to the rotation direction by rotating around the center point O1. The configuration of the third arc segment 503 makes the profile of the anti-rotation protrusion 511 smooth, not easy to get stuck, not easy to generate stress concentration points, and reduces wear.

[0118] Specifically, the distance from the center point O1 to any point on the third arc segment 503 is greater than half the length of the working line D1, so that the wedge block 51 will not rotate excessively when rotating around the center point O1.

[0119] In some specific embodiments, Figure 2 and Figure 3 As shown, at least two wedge blocks 51 in the same one-way transmission group 5 are first wedge blocks 51X, and the circumferential contour line of the first wedge block 51X also includes: a fourth arc segment 504, the fourth arc segment 504 is located on the side of the working line D1 away from the third arc segment 503, the fourth arc segment 504 is connected between the first arc segment 501 and the second arc segment 502, and the radius r4 of the fourth arc segment 504 is equal to half the length of the working line D1, that is, the radius r4 of the fourth arc segment 504>r0.

[0120] When two adjacent wedge blocks 51 are pressed tightly, the third arc segment 503 of the wedge block 51 adjacent to the first end 5A contacts the fourth arc segment 504 of the wedge block 51 adjacent to the second end 5B. This arrangement also utilizes the bulging shape of the fourth arc segment 504 to support the anti-rotation protrusion 511 of the adjacent wedge block 51, so that the adjacent wedge block 51 will not rotate excessively when rotating around the center point O1.

[0121] In some specific embodiments, Figure 3 and Figure 5As shown, the wedge block 51 at the first end 5A of at least one unidirectional transmission group 5 is a second wedge block 51Y, and the circumferential contour line of the second wedge block 51Y also includes: a first straight line segment 508, the first straight line segment 508 is located on the side of the working line D1 away from the third arc segment 503, and the first straight line segment 508 is connected between the first arc segment 501 and the second arc segment 502. One end of the elastic loading component 7 abuts against the location of the first straight line segment 508 of the second wedge block 51Y. In other words, the shape of the second wedge block 51Y in the first straight line segment 508 is a plane, so that positioning and assembling the elastic loading component 7 is more convenient and easy to operate.

[0122] In some specific embodiments, Figure 1-Figure 5 As shown, the wedge-type one-way clutch 10 includes an inner core body 1 and an outer ring body 3, both of which are annular, forming an annular retaining cavity 4. Three one-way transmission groups 5 are installed in the retaining cavity 4, and the same end of each one-way transmission group 5 in the circumferential direction is a first end 5A, and the other end in the circumferential direction is a second end 5B.

[0123] Each one-way transmission group 5 is provided with a centering column 53 at the first end 5A, and there are three centering columns 53 in total, which divide the holding cavity 4 into three 120-degree arc cavities, and a one-way transmission group 5 and an elastic loading component 7 are installed in each arc cavity.

[0124] At the first end 5A of the one-way transmission group 5, the wedge block 51 adjacent to the centering column 53 is the second wedge block 51Y, and an elastic loading component 7 is installed between the second wedge block 51Y and the centering column 53. The elastic loading component 7 squeezes all the wedge blocks 51 toward the second end 5B.

[0125] The remaining wedge blocks 51 are all first wedge blocks 51X, and the first wedge blocks 51X are peach-shaped.

[0126] The circumferential contour of the first wedge block 51X includes a first arc segment 501, a second arc segment 502, a third arc segment 503, a fourth arc segment 504, a fifth arc segment 505 and a second straight line 509. A convex point is formed at the third arc segment 503, constituting an anti-rotation protrusion 511.

[0127] The circumferential contour line of the second wedge block 51Y is substantially the same as that of the first wedge block 51X, except that the fourth arc segment 504 is replaced by a first straight segment 508, and both ends of the first straight segment 508 are connected to the first arc segment 501 and the second arc segment 502 through an arc. In this way, the squeezing force of the second wedge block 51Y on the first wedge block 51X is consistent with the squeezing force of the first wedge block 51X on the first wedge block 51X.

[0128] According to an embodiment of the utility model, the electric power-assisted bicycle comprises: a motor, an output shaft and a wedge-type one-way clutch 10 according to the above embodiment of the utility model. The structure of the wedge-type one-way clutch 10 is not described here. One of the inner core body 1 and the outer ring body 3 is connected to the motor, and the other is connected to the output shaft. In this way, the power of the motor can be transmitted to the output shaft in one direction. Such a configuration is conducive to the compactness of the structure of the power transmission part of the electric power-assisted bicycle, and it is not easy to loosen or fail.

[0129] In the description of the present invention, it should be understood that the terms "center", "length", "width", "thickness", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0130] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present utility model, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0131] In the present invention, unless otherwise clearly specified and limited, the terms "install", "connect", "connect", "fix" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection, or a communication; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0132] In the present utility model, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0133] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the utility model. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0134] Although the embodiments of the present invention have been shown and described, those skilled in the art will appreciate that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the claims and their equivalents.

Claims

1. A wedge-type one-way clutch, characterized in that: include: An inner core, wherein the outer peripheral surface of the inner core has a first circular track; An outer ring body, the outer ring body is arranged around the inner core body at intervals, the inner circumference of the outer ring body has a second circular track concentric with the first circular track, and a circular retaining cavity is formed between the inner circumference of the outer ring body and the outer circumference of the inner core body; At least one one-way transmission group, the one-way transmission group is arranged in the holding cavity and has two circumferential ends, respectively, the one-way transmission group comprises at least two wedge blocks closely arranged in sequence along the circumferential direction, each of the wedge blocks is provided with an anti-rotation protrusion protruding along the circumferential direction toward the second end, so as to press on the adjacent wedge block or the adjacent one-way transmission group; An elastic loading component is located in the retaining cavity, and the elastic loading component is arranged at the first end of the one-way transmission group and connected to the wedge block at the first end to press the wedge block toward the second end.

2. The sprag-type one-way clutch according to claim 1, characterized in that: The elastic loading assembly includes an elastic member, which is extended along a tangential direction of the first end and can be elastically deformed in the tangential direction of the first end.

3. The sprag-type one-way clutch according to claim 2, characterized in that: The elastic loading assembly further comprises: a top sleeve sleeved on at least one end of the elastic member.

4. The sprag-type one-way clutch according to claim 1, characterized in that: Each of the one-way transmission groups further includes: a centering column arranged at the first end, the axis of the centering column is fixedly spaced from the axis of the inner core, and the elastic loading assembly is connected between the centering column and the adjacent wedge block.

5. The sprag-type one-way clutch according to claim 4, characterized in that: A positioning hole is provided on at least one of the centering column and the adjacent wedge block, and at least one end of the elastic loading component is located in the positioning hole.

6. The sprag-type one-way clutch according to claim 4, characterized in that: The centering column is a rotating body, and the diameter of the centering column is equal to the difference between the radius of the second circular orbit and the radius of the first circular orbit.

7. The sprag-type one-way clutch according to claim 4, characterized in that: There are at least three one-way transmission groups, and there are at least three corresponding centering columns. A positioning shaft is provided at the center of each centering column, and one of the following methods is satisfied: Method 1: All the positioning shafts are connected to the inner core; Mode 2: All the positioning shafts are connected to the outer ring body; Mode three: the wedge-type one-way clutch also includes a side frame, and all the positioning shafts are connected to the side frame.

8. The sprag-type one-way clutch according to any one of claims 1 to 7, characterized in that: The wedge has a circumferential contour; The circumferential contour line includes an outer ring working point and an inner ring working point, a line connecting the outer ring working point to the inner ring working point is a working line, a length of the working line is equal to a difference between a radius of the second circular track and a radius of the first circular track, and when the outer ring working point contacts the first circular track, the inner ring working point contacts the second circular track; The anti-rotation protrusion is located on one side of the working line in the circumferential direction toward the second end; The midpoint of the working line is the center point of the circumferential contour line, and the line segment passing through the center point and intersecting with the circumferential contour line is the center line; The length of the through-center line between the anti-rotation protrusion and the inner ring working point at one end is greater than the length of the working connection line; The circumferential contour line has a symmetrical portion, and the central angle from the symmetrical portion to the inner ring working point and the central angle from the anti-rotation protrusion to the inner ring working point are equal. The length of the center line between one end of the symmetrical portion and the inner ring working point is shorter than the length of the working line.

9. The sprag-type one-way clutch according to claim 8, characterized in that: The center of gravity of the wedge block is located on the side of the working line facing the second end in the circumferential direction.

10. The sprag-type one-way clutch according to claim 9, characterized in that: The wedge block is provided with a weight-reducing hole, and the weight-reducing hole is located on one side of the working line in the circumferential direction toward the first end.

11. The sprag-type one-way clutch according to claim 8, characterized in that: The circumferential contour line includes: A first arc segment, the inner ring working point is located on the first arc segment, and the radius of the first arc segment is greater than half the length of the working line; A second arc segment, the outer ring working point is located on the second arc segment, and the radius of the second arc segment is greater than half the length of the working line; A third arc segment, one end of the third arc segment is connected to the first arc segment, the curvature of the third arc segment is greater than the curvature of the first arc segment, the third arc segment constitutes the contour line of the anti-rotation protrusion, and the distance from the center point to any point on the third arc segment is greater than half the length of the working line.

12. The sprag-type one-way clutch according to claim 11, characterized in that: At least two of the wedge blocks in the same one-way transmission group are first wedge blocks, and the circumferential contour line of the first wedge block also includes: a fourth arc segment, the fourth arc segment being located on a side of the working line away from the third arc segment, the fourth arc segment being connected between the first arc segment and the second arc segment, and the radius of the fourth arc segment being equal to half the length of the working line; When two adjacent wedge blocks are pressed tightly, the third arc segment of the wedge block adjacent to the first end contacts the fourth arc segment of the wedge block adjacent to the second end.

13. The sprag-type one-way clutch according to claim 11, characterized in that: The wedge block located at the first end in at least one of the one-way transmission groups is a second wedge block, and the circumferential contour line of the second wedge block further includes: A first straight line segment, the first straight line segment is located on a side of the working line away from the third arc segment, and the first straight line segment is connected between the first arc segment and the second arc segment; One end of the elastic loading component abuts against the first straight section of the second wedge block.

14. An electric power-assisted bicycle, characterized in that: include: Motor; Output shaft; According to any one of claims 1 to 13, the sprag-type one-way clutch, one of the inner core body and the outer ring body is connected to the motor, and the other is connected to the output shaft.

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