CN112228470B

CN112228470B - Overrunning clutch

Info

Publication number: CN112228470B
Application number: CN202011062630.3A
Authority: CN
Inventors: 王久成; 申春宝; 任宝强
Original assignee: FAW Group Corp
Current assignee: FAW Group Corp
Priority date: 2020-09-30
Filing date: 2020-09-30
Publication date: 2022-04-08
Anticipated expiration: 2040-09-30
Also published as: CN112228470A

Abstract

The invention relates to the technical field of clutches, and particularly discloses an overrunning clutch. The housing of the overrunning clutch is provided with the groove, one end of the friction block is arranged in the groove, two first side surfaces of the friction block are inclined planes to enable the section of the friction block to be in a trapezoid structure, the section of the groove is also in the trapezoid structure, the first side surfaces can be contacted with or separated from the groove wall of the groove to achieve combination or separation of the housing and the mandrel, the contact of the friction block and the housing belongs to low-pair friction of surface-to-surface contact, the structure can achieve friction self-locking, further combination and separation of the overrunning clutch are achieved, the opening and closing sensitivity is high, the performance is reliable, noise during working is low, bearing capacity is high, abrasion is not prone to occurring, stepless combination and separation impact is low, bidirectional locking and unidirectional locking of the overrunning clutch can be achieved by using the structure, and the use range is wide.

Description

Overrunning clutch

Technical Field

The invention relates to the technical field of clutches, in particular to an overrunning clutch.

Background

The overrunning clutch is a basic part appearing along with the development of mechanical and electrical integration products, is mainly used for an important part for realizing power transmission and separation functions between a driving shaft and a driven shaft in mechanical equipment, and can realize the self-clutch function by utilizing the speed change or the rotation direction change of the driving part and the driven part. When the driving part drives the driven part to rotate together, the wedging state is called; when the driving member and the driven member are disengaged to revolve at their respective speeds, an overrun condition is referred to.

The existing overrunning clutch mainly comprises a ratchet wheel type overrunning clutch, a roller type overrunning clutch and a wedge type overrunning clutch. The ratchet wheel type overrunning clutch mainly comprises a ratchet wheel, an active pawl, a non-return pawl, a rack and the like, and the ratchet wheel is pushed to rotate in a stepping mode through the motion of the active pawl. In the ratchet wheel type overrunning clutch, the stroke of the clutch can only be regulated in a step mode, and in addition, the sliding of the pawl on the tooth back easily causes noise and impact abrasion, so the ratchet wheel type overrunning clutch is not suitable for high-speed occasions; in the roller type overrunning clutch, torque and friction are transmitted mainly through rollers, and all force transmission units are mainly in linear contact, so that the stress area is increased by increasing the number of the rollers in the prior art, but the method has great limitation, and the service life of the product is still not long in high-load occasions; in the wedge type overrunning clutch, the selection of the wedging angle cannot give consideration to the abrasion resistance and the torque transmission performance, the smaller the wedging angle of the wedge block is, the better the wedging performance is, but the effective friction layer of the wedge block for bearing abrasion is reduced, the abrasion resistance is deteriorated, the service life of the wedge block is shortened, if the wedging angle is increased, although the effective friction layer is increased, the abrasion resistance is enhanced, the wedging performance is relatively weakened, and the torque bearing performance of the overrunning clutch is remarkably reduced.

The existing overrunning clutch cannot bear larger torque in a point contact or linear contact high-auxiliary transmission mode, has high contact stress, low bearing capacity, high cost and short service life, is easy to lose efficacy due to abrasion, and obviously reduces the working reliability and the service performance of equipment adopting the overrunning clutch.

Disclosure of Invention

The invention aims to provide an overrunning clutch which is high in bearing capacity, not easy to wear, small in stepless engagement and disengagement impact, free of noise and prolonged in service life.

In order to achieve the purpose, the invention adopts the following technical scheme:

an overrunning clutch comprising:

a mandrel;

the shell is sleeved outside the mandrel and is rotationally connected with the mandrel;

the friction block is provided with at least one friction block, one end of the friction block is hinged with the core shaft, two first side surfaces opposite to the friction block incline towards the end part of the other end of the friction block, the shell is provided with a groove matched with the friction block, and a connecting piece capable of enabling the first side surfaces to be in contact with or separated from the groove wall of the groove is further connected between the friction block and the core shaft;

the end part of the friction block is provided with a chute, the ball is arranged in the chute, a first elastic piece is arranged between the ball and the bottom of the chute, and the first elastic piece can enable the ball to move along the axial direction of the chute.

Preferably, one side of clutch blocks one end is equipped with the connecting block, the tip of connecting block is equipped with the arcwall face, be equipped with the articulated groove that has the arc lateral wall on the dabber, the tip of connecting block rotate install in the articulated inslot.

Preferably, the connecting piece comprises a second elastic piece, one end of the second elastic piece is connected with the other side of the end, provided with the connecting block, of the friction block, the other end of the second elastic piece is connected with the surface of the mandrel, and the second elastic piece can enable the friction block to move along the axial direction of the groove.

Preferably, the end surface of the friction block arranged in the groove is an arc surface which is arranged in an outward protruding mode.

Preferably, the friction blocks are provided with an even number, every two friction blocks are symmetrically arranged relative to the axis of the mandrel, and the inclined directions of the inclined grooves are the same.

Preferably, the friction blocks are provided with at least two friction blocks, wherein the inclined grooves on at least one friction block are inclined in the opposite direction to the inclined grooves on the other friction blocks.

Preferably, an even number of the friction blocks are provided, and at least four friction blocks are provided, every two friction blocks are symmetrically arranged relative to the axis of the mandrel, wherein the inclined grooves on at least one pair of the friction blocks are inclined in the opposite direction to the inclined grooves on the other friction blocks.

Preferably, the chute with other on the clutch blocks the chute slope opposite direction one of the clutch blocks be equipped with the boss on the first side, follow in the casing axial slip is equipped with the sliding sleeve, the sliding sleeve can with the boss cooperation is connected the messenger the clutch blocks first side with the cell wall separation of recess.

Preferably, the sliding sleeve is connected with a driving mechanism capable of driving the sliding sleeve to move axially along the shell.

Preferably, the shell is connected with the mandrel through a bearing, an outer ring of the bearing is connected with the shell through an inner snap spring, and an inner ring of the bearing is connected with the mandrel through an outer snap spring.

The invention has the beneficial effects that:

the housing of the overrunning clutch is provided with the groove, one end of the friction block is arranged in the groove, two first side surfaces of the friction block are inclined planes to enable the section of the friction block to be in a trapezoid structure, the section of the groove is also in the trapezoid structure, the first side surfaces can be contacted with or separated from the groove wall of the groove to achieve combination or separation of the housing and the mandrel, the contact of the friction block and the housing belongs to low-pair friction of surface-to-surface contact, the structure can achieve friction self-locking, further combination and separation of the overrunning clutch are achieved, the opening and closing sensitivity is high, the performance is reliable, noise during working is low, bearing capacity is high, abrasion is not prone to occurring, stepless combination and separation impact is low, bidirectional locking and unidirectional locking of the overrunning clutch can be achieved by using the structure, and the use range is wide.

Drawings

FIG. 1 is a front cross-sectional view of an overrunning clutch provided in accordance with one embodiment of the present invention;

FIG. 2 is a side cross-sectional view of an overrunning clutch provided in accordance with one embodiment of the present invention;

FIG. 3 is a front cross-sectional view of an overrunning clutch provided in accordance with a second embodiment of the present invention;

fig. 4 is a side sectional view of an overrunning clutch according to a second embodiment of the present invention.

In the figure:

1. a mandrel; 11. a hinge slot;

2. a housing; 21. a groove;

3. a friction block; 31. a first side surface; 32. a chute; 33. a boss;

4. a connecting member;

51. a ball bearing; 52. a first elastic member;

6. connecting blocks;

7. a sliding sleeve;

81. a bearing; 82. an inner snap spring; 83. and an outer clamp spring.

Detailed Description

In order to make the technical problems solved, technical solutions adopted and technical effects achieved by the present invention clearer, the technical solutions of the embodiments of the present invention will be described in further detail below with reference to the accompanying drawings, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

In the description of the present invention, unless expressly stated or limited otherwise, the terms "connected," "connected," and "fixed" are to be construed broadly, e.g., as meaning permanently connected, removably connected, or integral to one another; can be mechanically or electrically connected; either directly or indirectly through intervening media, either internally or in any other relationship. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.

In the present invention, unless otherwise expressly stated or limited, "above" or "below" a first feature means that the first and second features are in direct contact, or that the first and second features are not in direct contact but are in contact with each other via another feature therebetween. Also, the first feature being "on," "above" and "over" the second feature includes the first feature being directly on and obliquely above the second feature, or merely indicating that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature includes the first feature being directly under and obliquely below the second feature, or simply meaning that the first feature is at a lesser elevation than the second feature.

The overrunning clutch is provided in the embodiment to solve the problems that in the prior art, the overrunning clutch cannot bear large torque due to point contact or linear contact and other high-auxiliary transmission modes, the contact stress is high, the bearing capacity is low, the overrunning clutch is easy to wear to cause failure, the cost is high, the service life is short, and the working reliability and the service performance of equipment adopting the overrunning clutch are remarkably reduced.

Example one

As shown in fig. 1 and 2, the overrunning clutch provided in this embodiment includes a mandrel 1, a housing 2, at least one friction block 3 and balls 51, the housing 2 is sleeved outside the mandrel 1, the housing 2 is rotatably connected to the mandrel 1, one end of the friction block 3 is hinged to the mandrel 1, two first side surfaces 31 opposite to the friction block 3 are both inclined toward an end of the other end of the friction block 3, a groove 21 matched with the friction block 3 is formed in the housing 2, and a connecting member 4 capable of contacting or separating the first side surfaces 31 with or from a groove wall of the groove 21 is further connected between the friction block 3 and the mandrel 1; the end of the friction block 3 is provided with an inclined groove 32, the ball 51 is arranged in the inclined groove 32, a first elastic element 52 is arranged between the ball 51 and the bottom of the inclined groove 32, and the first elastic element 52 can enable the ball 51 to move along the axial direction of the inclined groove 32.

The housing 2 of the overrunning clutch provided by the embodiment is provided with the groove 21, one end of the friction block 3 is arranged in the groove 21, two first side surfaces 31 of the friction block 3 are inclined surfaces to enable the section of the friction block 3 to be of a trapezoid structure, the section of the groove 21 is of the trapezoid structure, the first side surfaces 31 can be in contact with or separated from the groove walls of the groove 21 to achieve combination or separation of the housing 2 and the mandrel 1, the friction block 3 and the housing 2 are in contact with each other in a surface-to-surface manner, friction self-locking can be achieved through the structure, combination and separation of the overrunning clutch can be achieved, opening and closing sensitivity is high, performance is reliable, noise is low during working, bearing capacity is high, abrasion is not prone to occurring, stepless combination and separation impact is small, bidirectional locking and unidirectional locking of the overrunning clutch can be achieved through the structure, and the use range is wide.

Specifically, the one end of dabber 1 is arranged in casing 2, and dabber 1 is connected with casing 2 through bearing 81, and the outer lane of bearing 81 is connected with casing 2 through interior jump ring 82, and the inner circle of bearing 81 is connected with dabber 1 through outer jump ring 83 to realize that casing 2 is connected with the rotation of dabber 1, connection structure is simple, easily implements, and is with low costs.

In this embodiment, one side of the one end of clutch block 3 is connected with connecting block 6, and the tip of connecting block 6 is equipped with the arcwall face, is equipped with the articulated groove 11 that has the arc lateral wall on the dabber 1, and the tip of connecting block 6 rotates to be installed in articulated groove 11. The friction block 3 is rotatably connected with the mandrel 1, and can realize the rotation of the friction block 3 relative to the mandrel 1 so as to realize the combination and separation of the friction block 3 and the shell 2.

The opposite side of the one end of clutch blocks 3 is provided with connecting piece 4, and connecting piece 4 includes the second elastic component, and the one end of second elastic component and the end connection of clutch blocks 3, the other end and the surface connection of dabber 1 of second elastic component, second elastic component enable clutch blocks 3 along the axial displacement of recess 21. When the overrunning clutch overruns, the friction block 3 compresses the second elastic piece, and the two first side surfaces 31 of the friction block 3 are separated from the groove walls of the groove 21.

The first elastic member 52 and the second elastic member are both springs, and have a simple structure and convenient use.

In the present embodiment, since the groove 21 is formed along the circumferential direction of the housing 2, the bottom of the groove 21 is an arc-shaped surface, which is easy to process, and therefore, the end surface of the friction block 3 disposed in the groove 21 is an arc-shaped surface protruding outward so as to be connected with the bottom of the groove 21 in a matching manner. Further, in order to facilitate the processing of the friction block 3, the end surface of one end of the friction block 3, which is connected with the connecting block 6, is an arc-shaped surface which is arranged in an inward protruding manner.

In this embodiment, it is preferable that the two first side surfaces 31 of the friction block 3 have the same inclination angle, so that the section of the friction block 3 is isosceles trapezoid, which can make the two sides of the friction block 3 uniformly stressed and facilitate the processing of the friction block 3. The two first sides 31 of the friction block 3 may be inclined at different angles, which is not limited herein.

The inclination angle of the two first sides 31 of the friction block 3 is related to the material of the friction block 3, and different materials are used for the friction block 3, and the friction coefficients are different. The angle at which the first side surface 31 is inclined depends on the material of the friction block 3, so that the friction block 3 and the housing 2 can be flexibly coupled and decoupled. Typically, the first side 31 is inclined at an angle of 5-10 °.

In the present embodiment, an even number of friction blocks 3 are preferably provided, and every two friction blocks 3 are symmetrically arranged relative to the axis of the mandrel 1, and the inclined directions of the inclined grooves 32 are the same, so as to form a one-way overrunning clutch. The friction blocks 3 are even in number, and every two friction blocks 3 are symmetrically arranged, so that the use stability of the overrunning clutch and the connection strength of the shell 2 and the mandrel 1 are improved.

When the overrunning clutch is used, the speed of clockwise rotation of the spindle 1 is n1, the clockwise rotation speed of the shell 2 is n2, when n1 is not less than n2, the balls 51 compress the first elastic piece 52 in the chute 32 of the friction block 3, the balls 51 roll to the position a in the chute 32, at the moment, the two first side surfaces 31 of the friction block 3 and the groove wall of the groove 21 of the shell 2 are in a wedged state, and the spindle 1 and the shell 2 are in a combined state and do not overrun; when n1 is less than n2, and the speed of the shell 2 is greater than that of the mandrel 1, the balls 51 roll to a position close to the top b along the inclined grooves 32 of the friction blocks 3 under the action of the first elastic pieces 52, the balls 51 press the friction blocks 3, the friction blocks 3 compress the second elastic pieces to contract towards the center of the mandrel 1, so that the two first side surfaces 31 of the friction blocks 3 are separated from the groove walls of the grooves 21 of the shell 2, at the moment, the shell 2 and the mandrel 1 are in an overrunning idle state under the supporting action of the bearings 81, and when n1 is more than or equal to n2 again, the actions are repeated.

Example two

As shown in fig. 3 and 4, the overrunning clutch provided in the present embodiment is different from the overrunning clutch provided in the first embodiment in that at least two friction blocks 3 are provided, wherein the inclined grooves 32 on at least one friction block 3 are inclined in a direction opposite to the inclined grooves 32 on the other friction blocks 3, so that the overrunning clutch can be bidirectionally locked to form a bidirectional overrunning clutch.

Further, an even number of friction blocks 3 are provided, and at least four friction blocks 3 are provided, and every two friction blocks 3 are symmetrically arranged relative to the axis of the mandrel 1, wherein the inclined grooves 32 on at least one pair of friction blocks 3 are inclined in the opposite direction to the inclined grooves 32 on the other friction blocks 3. The friction blocks 3 are even in number, and every two friction blocks 3 are symmetrically arranged, so that the use stability of the overrunning clutch and the connection strength of the shell 2 and the mandrel 1 are improved.

A boss 33 is arranged on a first side surface 31 of the friction block 3, the inclined direction of the inclined groove 32 is opposite to that of the inclined grooves 32 on other friction blocks 3, a sliding sleeve 7 is arranged in the shell 2 in a sliding mode along the axial direction of the shell 2, and the sliding sleeve 7 can be matched and connected with the boss 33 to enable the first side surface 31 of the friction block 3 to be separated from the groove wall of the groove 21. The boss 33 is matched and connected with the sliding sleeve 7, and the friction block 3 is controlled not to contact with the groove 21, so that the overrunning clutch becomes one-way locking so as to be convenient for the overrunning clutch to overrun. When the overrunning clutch is combined, the sliding sleeve 7 can be separated from the boss 33, so that the overrunning clutch is locked in two directions.

Further, the sliding sleeve 7 is connected with a driving mechanism capable of driving the sliding sleeve 7 to move along the circumferential direction of the housing 2, and the driving mechanism may be an electromagnet, or may be another structure, which is not limited herein.

The friction block 3 in which the inclined grooves 32 of one group are inclined in the same direction is defined as a clockwise mounted friction block 3, and the friction block 3 in the opposite direction to the inclined grooves 32 of the clockwise mounted friction block 3 is defined as a counterclockwise mounted friction block 3. When the overrunning clutch is used, the speed of clockwise rotation of the spindle 1 is n1, the clockwise rotation speed of the shell 2 is n2, when n1 is more than or equal to n2, the balls 51 compress the first elastic piece 52 in the inclined groove 32 of the friction block 3 for the friction block 3 which is installed clockwise, the balls 51 roll to the position a in the inclined groove 32, at the moment, the two first side surfaces 31 of the friction block 3 and the groove wall of the groove 21 of the shell 2 are in a wedged state, and the spindle 1 and the shell 2 are in a combined state and do not overrun; the ball 51 of the friction block 3 which is installed anticlockwise presses the friction block 3, the friction block 3 compresses the second elastic piece to shrink towards the center of the mandrel 1, so that the two first side surfaces 31 of the friction block 3 are separated from the groove wall of the groove 21 of the shell 2, the friction block 3 rotates for a certain angle relative to the mandrel 1, the sliding sleeve 7 moves towards the friction block 3 and is connected with the boss 33 on the friction block 3 to prevent the friction block 3 from being combined with the groove 21, and the clutch becomes a one-way overrunning clutch. Then when n1 < n2 and the speed of the shell 2 is greater than that of the mandrel 1, the balls 51 of the friction block 3 which is installed clockwise roll to a position close to the top b along the inclined grooves 32 of the friction block 3 under the action of the first elastic piece 52, the balls 51 press the friction block 3, the friction block 3 compresses the second elastic piece to contract towards the center of the mandrel 1, so that the two first side surfaces 31 of the friction block 3 are separated from the groove walls of the grooves 21 of the shell 2, the shell 2 is in an overrun idle state with the mandrel 1 under the supporting action of the bearing 81, and when n1 is more than or equal to n2 again, the shell 2 is combined with the mandrel 1.

In addition, when the sliding sleeve 7 is not connected with the boss 33, the friction block 3 which is installed anticlockwise can move freely, at the moment, the spindle 1 and the shell 2 are in a bidirectional locking state, and the overrunning clutch cannot overrun.

It should be understood that the above-described embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. Other variations and modifications will be apparent to persons skilled in the art in light of the above description. And are neither required nor exhaustive of all embodiments. Any modification, equivalent replacement, and improvement made within the spirit and principle of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. An overrunning clutch, comprising:

a mandrel (1);

the shell (2) is sleeved outside the mandrel (1), and the shell (2) is rotatably connected with the mandrel (1);

the friction block (3) is arranged, one end of the friction block (3) is hinged to the mandrel (1), two first side surfaces (31) opposite to the friction block (3) incline towards the end part of the other end of the friction block (3), a groove (21) matched with the friction block (3) is formed in the shell (2), and a connecting piece (4) capable of enabling the first side surfaces (31) to be in contact with or separated from the groove wall of the groove (21) is further connected between the friction block (3) and the mandrel (1);

the ball (51), inclined groove (32) have been seted up to the other end tip of clutch blocks (3), ball (51) are placed in inclined groove (32), be equipped with first elastic component (52) between ball (51) and the tank bottom of inclined groove (32), first elastic component (52) enable ball (51) are followed the axial displacement of inclined groove (32).

2. The overrunning clutch according to claim 1, wherein a connecting block (6) is arranged on one side of one end of the friction block (3), an arc-shaped surface is arranged at the end part of the connecting block (6), a hinge groove (11) with an arc-shaped side wall is arranged on the mandrel (1), and the end part of the connecting block (6) is rotatably arranged in the hinge groove (11).

3. Overrunning clutch according to claim 2, characterized in that the connecting element (4) comprises a second elastic element, one end of which is connected to the other side of the friction block (3) where the connecting piece (6) is located, and the other end of which is connected to the surface of the spindle (1), the second elastic element being able to move the friction block (3) in the axial direction of the groove (21).

4. The overrunning clutch according to claim 1, wherein the end surface of the friction block (3) disposed in the groove (21) is an arc surface protruding outwards.

5. Overrunning clutch according to claim 1, characterized in that an even number of friction blocks (3) are provided, and every two friction blocks (3) are symmetrically arranged with respect to the axis of the spindle (1), and the inclined directions of the inclined grooves (32) are the same.

6. Overrunning clutch according to claim 1, characterized in that the friction blocks (3) are provided with at least two, wherein the inclined slots (32) on at least one of the friction blocks (3) are inclined in the opposite direction to the inclined slots (32) on the other friction block (3).

7. The overrunning clutch according to claim 6, wherein an even number of friction blocks (3) are provided, and at least four friction blocks (3) are provided, and each two friction blocks (3) are symmetrically arranged relative to the axis of the mandrel (1), wherein the inclined grooves (32) on at least one pair of friction blocks (3) are inclined in the opposite direction to the inclined grooves (32) on the other friction blocks (3).

8. The overrunning clutch according to claim 6 or 7, wherein a boss (33) is arranged on one first side surface (31) of the friction block (3) of the inclined groove (32) of the friction block (32) opposite to the inclined direction of the inclined groove (32) of the other friction block (3), a sliding sleeve (7) is arranged in the housing (2) along the axial direction of the housing (2) in a sliding manner, and the sliding sleeve (7) can be matched and connected with the boss (33) to separate the first side surface (31) of the friction block (3) from the groove wall of the groove (21).

9. The overrunning clutch according to claim 8, wherein a driving mechanism capable of driving the sliding sleeve (7) to move axially along the housing (2) is connected to the sliding sleeve (7).

10. Overrunning clutch according to claim 1, wherein the housing (2) is connected to the spindle (1) by a bearing (81), the outer ring of the bearing (81) is connected to the housing (2) by an inner snap spring (82), and the inner ring of the bearing (81) is connected to the spindle (1) by an outer snap spring (83).