CN106090068A - A kind of freewheel clutch - Google Patents

Abstract

The invention discloses an overrunning clutch, which comprises: an operating rod, the first end of which is used to bear the applied load; a first cover plate connected with the second end of the operating rod; The rotating block; the second cover plate connected with the other side of the middle rotating block; the internal and external tooth rotating ratchet coaxial with the intermediate rotating block, and the external tooth of the internal and external tooth rotating ratchet and the internal tooth of the internal and external tooth rotating ratchet. The mounting track of the ball, the first cover plate and the second cover plate respectively support the two ends of the ball installed in the mounting track; the first end is rotatably connected to the pawl of the middle rotating block, and the second end of the pawl is opposite to the pawl The first end of the pawl is arranged counterclockwise and the second end of the pawl is capable of meshing with the internal teeth of the ratchet. The force that the ratchet provides to the internal and external teeth to rotate the ratchet is direct transmission force, not frictional force, which reduces component wear and avoids stress concentration, and a lever is formed between the ratchet, the middle rotating block and the operating rod, and large torque can be transmitted.

Description

an overrunning clutch

technical field

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

Background technique

As the basic part of electromechanical equipment transmission, the overrunning clutch is widely used between the prime mover and the working machine or between the driving shaft and the driven shaft inside the machine for power transmission and separation. It is a device that uses the speed change of the main and driven parts or the transformation of the rotation direction to realize the self-clutch function. At present, the overrunning clutches used mainly include roller overrunning clutches and sprag overrunning clutches, but because they are all torque transmissions through the transmission force of small pawls accompanied by friction, and the torque transmitted between parts is small, the pawls Concentrated contact stress, short life due to wear between structural parts, etc., are difficult to apply to transmission mechanisms in more mechanical equipment.

Therefore, how to reduce the stress concentration of the torque transmission components inside the overrunning clutch and how to increase the transmission torque of the components is a technical problem to be solved urgently by those skilled in the art.

Contents of the invention

In view of this, the object of the present invention is to provide an overrunning clutch to reduce the stress concentration of the internal torque transmission components of the overrunning clutch and increase the transmission torque of the components.

In order to achieve the above object, the present invention provides the following scheme:

An overrunning clutch comprising:

an operating rod having a first end adapted to bear the applied load;

a first cover connected to the second end of the operating rod;

an intermediate rotating block connected to the first cover on one side;

a second cover connected to the other side of the middle rotating block;

A rotary ratchet with internal and external teeth coaxial with the middle rotating block, and the rotary ratchet with internal and external teeth is installed between the first cover plate and the second cover plate, the external teeth of the rotary ratchet with internal and external teeth and There is a first installation track for installing balls between the outer teeth of the internal and external tooth rotary ratchet, and the first cover plate and the second cover plate respectively support the two ends of the balls installed in the first installation track ;

The first end of the pawl is rotatably connected to the middle rotating block, the second end of the pawl is arranged counterclockwise relative to the first end of the pawl, and the second end of the pawl can be connected to the said pawl. The internal teeth of the ratchet mesh.

Preferably, in the above-mentioned overrunning clutch, a spring is further arranged between the intermediate rotating block and the pawl.

Preferably, the above-mentioned overrunning clutch further includes a connecting rod and a nested chuck rotatably connected to the connecting rod;

The nested chuck is rotatably connected to the second cover plate;

A first groove is opened on the middle rotating block;

The connecting rod swings in the first groove, and the first end of the connecting rod is connected with the nested chuck, and the second end of the connecting rod is connected with the pawl;

When the connecting rod swings in the first groove, the pawl can be driven to engage and separate from the internal teeth of the ratchet.

Preferably, in the above-mentioned overrunning clutch, a second groove is formed on the intermediate rotating block, and the first groove communicates with the second groove;

The nested chuck is provided with an arc-shaped protrusion, and the arc-shaped protrusion can rotate in the second groove.

Preferably, in the above-mentioned overrunning clutch, a pawl control chuck is also included;

The pawl control chuck is connected to the nest chuck.

Preferably, in the above-mentioned overrunning clutch, a pawl control lever is also included;

The pawl control rod is arranged on the pawl control chuck.

Preferably, in the above-mentioned overrunning clutch, the pawl control lever is arranged on the edge of the pawl control chuck.

Preferably, in the above-mentioned overrunning clutch, a tripod is provided at the end of the operating rod;

The tripod includes three support rods, and a first bolt hole is opened on the support rod, and the support rod and the three cylindrical threaded holes of the first cover plate are matched with the threaded holes by screws connect.

Preferably, in the above-mentioned overrunning clutch, the operating rod is a hollow structure with reinforcing ribs inside, the three support rods are distributed at 120 degrees, and each of the support rods is provided with a The second bolt hole for the connection.

Preferably, in the above-mentioned overrunning clutch, the first cover plate and the second cover plate are further provided with a second ball mounting track for supporting the balls.

It can be seen from the above technical solutions that in the overrunning clutch provided by the present invention, the first cover plate and the second cover plate support the middle rotating block, and the balls located between the first cover plate and the second cover plate support the internal and external tooth rotating ratchet. When the overrunning clutch provided by the present invention is used, a load is applied to the first end of the operating rod. When the load causes the operating rod to rotate counterclockwise, it drives the first cover plate and the second cover plate to rotate counterclockwise, and then drives the middle rotating block counterclockwise. Turn, at this time, under the action of centrifugal force, the pawl connected to the middle rotating block will rotate away from the middle rotating block, so that the second end of the pawl can mesh with the internal teeth of the ratchet, and then drive the internal and external teeth to rotate the ratchet Rotate, and the gear meshing with the external teeth of the internal and external tooth rotary ratchet can also rotate synchronously; when the load makes the operating rod rotate clockwise, it will drive the first cover plate and the second cover plate to rotate clockwise, and then drive the middle rotating block clockwise At this time, under the action of centripetal force, the pawl connected to the middle rotating block will rotate towards the direction close to the middle rotating block, so that the second end of the pawl is separated from the internal teeth of the ratchet, and the internal and external teeth rotate the ratchet. The external teeth stop rotating, and the gear meshed with the outer wheel of the internal and external tooth rotary ratchet also stops rotating. In the overrunning clutch provided by the present invention, since the pawl can mesh with the internal teeth of the internal and external tooth rotating ratchet, the force applied by the pawl to the internal and external tooth rotating ratchet is a direct rotational force rather than a frictional force in the prior art. The transmission force avoids the stress concentration caused by the pressure on the ratchet, and can transmit a large moment. Since there is no friction, the wear between the ratchet and the internal and external tooth rotating ratchet is avoided. The lever formed by the connection between the ratchet, the middle rotating block and the operating rod can not only avoid stress concentration, but also transmit large torque.

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are only These are some embodiments of the present invention. Those skilled in the art can also obtain other drawings based on these drawings without creative work.

Fig. 1 is the top structural schematic diagram of the overrunning clutch provided by the present invention;

Fig. 2 is the isolateral structural representation of the overrunning clutch provided by the present invention;

Fig. 3 is a right view structure diagram of an overrunning clutch provided by the present invention;

Fig. 4 is a structural schematic diagram of an overrunning clutch provided by the present invention in an overrunning state;

Fig. 5 is a schematic structural view of the overrunning clutch provided by the present invention in a synchronous state;

Fig. 6 is a structural schematic diagram of the first cover plate of the overrunning clutch provided by the present invention;

Fig. 7 is another structural schematic diagram of the first cover plate of the overrunning clutch provided by the present invention;

Fig. 8 is a schematic structural view of the second cover plate of the overrunning clutch provided by the present invention;

Fig. 9 is another structural schematic diagram of the second cover plate of the overrunning clutch provided by the present invention;

Fig. 10 is a structural schematic diagram of the pawl of the overrunning clutch provided by the present invention;

Fig. 11 is a schematic structural view of the nested chuck of the overrunning clutch provided by the present invention;

Fig. 12 is another structural schematic diagram of the nested chuck of the overrunning clutch provided by the present invention;

Fig. 13 is a schematic structural view of the intermediate rotating block of the overrunning clutch provided by the present invention;

Fig. 14 is a structural schematic diagram of the internal and external tooth rotary ratchet of the overrunning clutch provided by the present invention.

Among them, in Figure 1-14:

Operating lever 1, first cover plate 2, middle rotating block 3, second cover plate 4, third cylindrical pin 401, internal and external tooth rotary ratchet 5, internal tooth 501, external tooth 502, pawl 6, spring 7, connecting rod 8. Nesting chuck 9, first groove 301, second groove 302, pawl control chuck 10, pawl control rod 11, tripod 12, support rod 1201, bearing bearing hole 1202, first cylindrical pin 201, the first Two cylindrical pins 202, oblique taper holes 203, cylindrical pin holes 402, hollow cylinders 403, middle holes 303, arc protrusions 901, arc projections 902, cylindrical pins 903, first connecting rod cylindrical pin holes 801, second Connecting rod cylindrical pin hole 802 , ball 13 , first installation track 14 .

detailed description

In order to enable those skilled in the art to better understand the technical solutions of the present invention, the present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments.

Embodiment one

Please refer to FIGS. 1-14 , the present invention discloses an overrunning clutch, including: an operating rod 1 , a first cover plate 2 , a second cover plate 4 , an intermediate rotating block 3 , a rotating ratchet wheel 5 with internal and external teeth, and a pawl 6 . Wherein, the first end of the operating rod 1 is used to bear the applied load, the second end of the operating rod 1 is connected with the first cover plate 2, the middle rotating block 3 is connected with one side of the first cover plate 2, and the second cover plate 4 Connected with the other side of the middle rotating block 3, the internal and external tooth rotating ratchet 5 is coaxial with the middle rotating block 3, and the internal and external tooth rotating ratchet 5 is installed between the first cover plate 2 and the second cover plate 4, and the internal and external tooth rotating ratchet There is a first installation track 14 for installing the ball 13 between the outer teeth 502 of the ratchet 5 and the outer teeth 502 of the internal and external tooth rotary ratchet 5, wherein the size of the through hole matches the size of the ball 13 so that the ball 13 can be installed in the first installation. Rotate in the track 14, and the ball 13 can prevent the first cover plate 2 and the second cover plate 4 from contacting the internal and external tooth rotating ratchet 5, and the first cover plate 2 and the second cover plate 4 respectively support the balls installed in the through holes 13; the first end of the ratchet 6 is rotatably connected with the middle rotating block 3, the second end of the ratchet 6 is set counterclockwise with respect to the first end of the ratchet 6 and the second end of the ratchet 6 can be connected with The internal teeth 501 of the ratchet are engaged.

Among them, the present invention also discloses that the material of the first cover plate 2 is 45 steel, the hardness after heat treatment reaches HRC40-60, and two symmetrical first cylindrical pins 201 are designed on the side facing the middle rotating block 3, the first cylindrical pin The center of 201 has a first threaded hole with a diameter of 3 mm. The first cover plate 2 can form a hinge through the first cylindrical pin 201 and the limit hole on the middle rotating block 3, and pass through the first threaded hole with a screw. The screw holes opened on the second cover plate 4 are fixedly connected. Thereby realize that the first cover plate 2 is synchronized with the middle rotating block 3; the first cover plate 2 is designed with a second cylindrical pin 202 on the side facing away from the middle rotating block 3, and its center also has a threaded hole with a diameter of 3 mm, which is compatible with The operating rod 1 is connected by screws to realize the synchronization between the operating rod 1 and the first cover plate 2. In addition, the first cover plate 2 is also designed with two symmetrical oblique conical holes 203, which are fastened to the second cover plate 4 by bolts.

The material of the second cover plate 4 is 45 steel, and the hardness reaches HRC40-60 after heat treatment. Two symmetrical third cylindrical pins 401 are designed on the side of the forward middle rotating block 3, and the center of the third cylindrical pin 401 has a diameter of The second threaded hole of 3 mm, the second cover plate 4 is also designed with two symmetrical cylindrical pin holes 402 on the side away from the middle rotating block 3, and the second cover plate 4 and the first cover plate 2 are fastened by bolts. The protruding hollow cylinder 403 on the second cover plate 4 is the place for placing the bearing, and there is an adjustment limit hole beside the hollow cylinder 403 .

The material of the internal and external tooth rotary ratchet 5 is 45 steel, and the hardness reaches HRC50～70 after heat treatment. Step teeth arranged in an arc.

The material of the middle rotating block 3 is 45 steel, and the hardness reaches HRC60-70 after heat treatment. There is a middle hole 303 in the middle of the middle rotating block 3, and the middle hole 303 is the nesting position of the hollow cylinder 403 of the second cover plate 4. The cylindrical pin hole 402 is in the It is symmetrically distributed on the middle rotating block 3, and symmetrically distributed on the edge of the middle rotating block 3 are the placement positions of two pawls 6 designed in a Taiji pattern, and pin holes are opened at these positions.

The shape of the pawl 6 is designed in a Tai Chi pattern. According to the principle of leverage, the circular arc where the elongated pawl 6 is located is designed so that the middle rotating block 3 and the operating rod 1 become a long lever as much as possible, so as to reduce the applied torque and the pawl 6 produces a large thrust. Its material is 45 steel, and its hardness reaches HRC60-70 after heat treatment. The round pin hole at one end can be hinged with the middle rotating block 3 through a pin, and the other end is the pin hole with the connecting rod 8 hinged.

In the overrunning clutch provided by the present invention, the first cover plate 2 and the second cover plate 4 support the middle rotating block 3 , and the ball 13 located between the first cover plate 2 and the second cover plate 4 supports the internal and external tooth rotating ratchet 5 . When the overrunning clutch provided by the present invention is used, a load is applied to the first end of the operating rod 1. When the load causes the operating rod 1 to rotate counterclockwise, it drives the first cover plate 2 and the second cover plate 4 to rotate counterclockwise, and then drives the middle The rotating block 3 rotates counterclockwise. At this time, under the action of centrifugal force, the pawl 6 connected to the intermediate rotating block 3 will rotate away from the intermediate rotating block 3, so that the second end of the pawl 6 can rotate with the inner and outer teeth The internal teeth of the ratchet 5 mesh, and then drive the internal and external tooth rotary ratchet 5 to rotate, so that the gear meshing with the external teeth of the internal and external rotary ratchet 5 can also rotate synchronously; when the load makes the operating rod 1 rotate clockwise, it drives the first cover The plate 2 and the second cover plate 4 rotate clockwise, and then drive the middle rotating block 3 to rotate clockwise. At this time, under the action of centripetal force, the pawl 6 connected with the middle rotating block 3 will move towards the direction of the middle rotating block 3 Rotate, make the second end of ratchet 6 break away from the internal tooth 501 of ratchet, and then make the external tooth 502 of internal and external tooth rotating ratchet 5 stop rotating, and the gear that meshes with the outer wheel of internal and external tooth rotating ratchet 5 also stops rotating. In the overrunning clutch provided by the present invention, since the pawl 6 can mesh with the internal teeth 501 of the internal and external tooth rotary ratchet 5, the force that the pawl 6 gives to the internal tooth 501 of the internal and external tooth rotary ratchet 5 is a rotational force, rather than the prior art In this way, the stress concentration caused by the pressure on the ratchet 6 is avoided, and a large moment can be transmitted. Since there is no friction, the wear between the ratchet 6 and the internal and external tooth rotating ratchet 5 is avoided. The lever formed by the connection of the long ratchet 6, the middle rotating block 3 and the operating rod 1 can avoid stress concentration and transmit large moment.

Embodiment two

In yet another embodiment of the present invention, the structure of the overrunning clutch in this embodiment is similar to that in the first embodiment, and the similarities will not be repeated, and only the differences will be introduced.

In the embodiment, it is specifically disclosed that a spring 7 is further arranged between the middle rotating block 3 and the ratchet 6 . Wherein, the spring 7 plays the role of tension and compression.

Further, the present invention discloses that the overrunning clutch also includes a connecting rod 8 and a nested chuck 9 rotatably connected to the connecting rod 8; the nested chuck 9 is rotatably connected to the second cover plate 4; There is a first groove 301; the connecting rod 8 swings in the first groove 301, and the first end of the connecting rod 8 is connected with the nested chuck 9, and the second end of the connecting rod 8 is connected with the pawl 6; the connecting rod 8 is in the Swinging in the first slot 301 can drive the pawl 6 to mesh with and separate from the internal teeth 501 of the internal and external tooth rotary ratchet 5 . The connecting rod 8 is used to drive the ratchet 6 to rotate in a direction close to the nested chuck 9 or away from the nested chuck 9 to realize the engagement and separation of the ratchet 6 and the internal teeth 501 of the internal and external tooth rotary ratchet 5 .

Further, the present invention discloses that there is a second groove 302 on the middle rotating block 3, and the first groove 301 communicates with the second groove 302; The jack 901 can rotate in the second groove 302. The second slot 302 is an arc slot, and the first slot 301 is a rectangular slot. Wherein, the nested chuck 9 is also provided with arc projections 902, and the number of the arc projections 902 is two, which are arranged on the surface of the nest chuck 9 away from the first cover plate 2, and the arcs Threaded connection holes are provided on the bump 902, and the pawl control chuck 10 can be connected by bolts. The side of the nested chuck 9 facing the first cover plate 2 is also provided with a cylindrical pin 903, and the cylindrical pin 903 is connected with the connecting rod 8. The first connecting rod cylindrical pin hole 801 on the first end of the connecting rod 8 is hingedly connected, while the second connecting rod cylindrical pin hole 802 on the second end of the connecting rod 8 is hinged with the pin hole on the ratchet 6 through a pin.

The second groove 302 is the position where the nested chuck 9 is placed, therefore, the surface requires milling to be smooth. Intersecting the second slot 302 is a first slot 301 with two parallel sides, and the first slot 301 allows the connecting rod 8 to swing therein. The ratchet 6 is a long arc-shaped ratchet 6, and a symmetrically distributed spring 7 placement hole is designed in the radial arc section of the middle rotating block 3 .

In order to facilitate the control of the rotation of the nested chuck 9 , the invention discloses that the overrunning clutch further includes a pawl control chuck 10 ; the pawl control chuck 10 is connected with the nested chuck 9 . The control of the rotation of the nested chuck 9 is realized by controlling the pawl to control the chuck 10 .

In order to facilitate the rotation of the pawl control chuck 10 , the present invention discloses that the overrunning clutch further includes a pawl control rod 11 ; the pawl control rod 11 is arranged on the pawl control chuck 10 .

Among them, the working angle of the nested chuck 9 is 0-30 degrees, and the working method is: pull the pawl control rod 11, and the pawl control rod 11 is fixed on the pawl control chuck 10 by screws to realize the pawl control chuck 10 Rotate synchronously, thereby driving the nested chuck 9 to rotate 0-30 degrees, and the nested chuck 9 drives the connecting rod 8 to swing and telescopically move through the hinge, so as to realize the opening and closing of the internal teeth of the ratchet 6 and the internal and external tooth rotating ratchet 5 Close up. In the present invention, when the ratchet external teeth 502 are meshed with other gears, when emergency braking or shutdown is encountered or no synchronization is required, the ratchet control lever 11 can be adjusted to make the ratchet 6 turn to constant separation, in a clockwise and counterclockwise position. Beyond state.

In order to realize the control of the ratchet 6 in a labor-saving manner, the present invention discloses that in the overrunning clutch, the ratchet control rod 11 is arranged on the edge of the ratchet control chuck 10 . It should be noted that arranging the pawl control rod 11 on the edge of the pawl control chuck 10 is only the most labor-saving way, and the position of the pawl control rod 11 can also be changed according to actual needs.

Further, the present invention also discloses that the end of the operating rod 1 is provided with a tripod 12; the tripod 12 includes three support rods 1201, and the first bolt holes are opened on the support rods 1201, and the support rods 1201 and the first cover plate 2 The threaded holes of the three cylinders are connected by screws and the threaded holes.

The present invention also discloses that the operating rod 1 is a hollow structure with reinforcing ribs inside. Three support rods 1201 are distributed at 120 degrees, and each support rod 1201 has a second bolt hole connected to the first cover plate 2 . The center of the tripod 12 has a bearing bearing hole 1202 for placing the first bearing and installing it on the stepped shaft.

In order to realize the supporting stability of the balls 13 , the present invention discloses that the first cover plate 2 and the second cover plate 4 are also provided with a second installation track for supporting the balls 13 . A partial circular arc with a diameter of 4 mm is designed at the edges of the first cover plate 2 and the second cover plate 4 as the second installation track for the ball movement.

In the overrunning clutch provided by the present invention, the first cover plate 2 and the second cover plate 4 support the middle rotating block 3 , and the ball 13 located between the first cover plate 2 and the second cover plate 4 supports the internal and external tooth rotating ratchet 5 . When the overrunning clutch provided by the present invention is used, a load is applied to the first end of the operating rod 1. When the load causes the operating rod 1 to rotate counterclockwise, it drives the first cover plate 2 and the second cover plate 4 to rotate counterclockwise, and then drives the middle The rotating block 3 rotates counterclockwise. At this time, under the action of the spring force 7 on the upper side of the middle rotating block 3 and the centrifugal force, the pawl 6 connected to the middle rotating block 3 will rotate away from the direction of the middle rotating block 3, so that The second end of the ratchet 6 can mesh with the internal teeth of the internal and external tooth rotary ratchet 5, and then drive the internal and external tooth rotary ratchet 5 to rotate, so that the gear meshing with the external teeth of the internal and external tooth rotary ratchet 5 can also rotate synchronously; when the load makes When the operating rod 1 rotates clockwise, it drives the first cover plate 2 and the second cover plate 4 to rotate clockwise, and then drives the middle rotating block 3 to rotate clockwise, and the middle rotating block 3 drives the ratchet and compresses the spring 7 for intermittent separation. What is realized at this time is the general clutch function, that is, the overrunning state. The pawl 6 is controllable when the second end of the pawl 6 meshes with the internal teeth of the internal and external tooth rotating ratchet 5, that is, in a synchronous state, when the external teeth of the ratchet 5 mesh with other gears, emergency braking or shutdown occurs. Or when the synchronous state is not required, the second end of the ratchet 6 can be disengaged from the inner teeth of the ratchet wheel by adjusting the ratchet control lever 11 to turn to the constant separation, and it is in the forward and counterclockwise overriding state.

In the overrunning clutch provided by the present invention, since the pawl 6 can mesh with the internal teeth of the internal and external tooth rotating ratchet 5, the power of the pawl 6 to the internal teeth of the internal and external tooth rotating ratchet 5 is a direct transmission force, rather than that of the prior art. The transmission force accompanied by frictional force, the lever formed by the connection between the long pawl 6 and the middle rotating block 3 and the operating rod 1 can not only avoid stress concentration, but also transmit large torque, because the pawl control rod 11 can control The engagement and separation of the ratchet 6 reduces wear between the ratchet 6 and the rotating ratchet 5 with internal and external teeth.

The overrunning clutch disclosed by the present invention has the following advantages:

(1) Reduce the stress concentration and wear of the pawl 6;

(2) Transmission of high torque.

(3) The pawl 6 is controllable.

(4) Multi-bearing bearings reduce the wear of each component.

In the present invention, "first", "second", etc. are for distinction in description, and have no other special meanings.

The above description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Accordingly, the present invention will not be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and inventive features disclosed herein.

Claims (10)

1. A kind of overrunning clutch, is characterized in that, comprises: An operating rod (1), the first end of the operating rod (1) is used to bear the applied load; a first cover plate (2) connected to the second end of the operating rod (1); an intermediate rotating block (3) connected to the first cover plate (2) on one side; a second cover plate (4) connected to the other side of the middle rotating block (3); The internal and external tooth rotating ratchet (5) coaxial with the middle rotating block (3), and the internal and external tooth rotating ratchet (5) is installed on the first cover plate (2) and the second cover plate ( 4) Between the internal teeth (501) of the internal and external tooth rotary ratchet (5) and the external teeth (502) of the internal and external tooth rotary ratchet (5), there is a first installation track for installing balls (13) (14), the first cover plate (2) and the second cover plate (4) respectively support the two ends of the ball (13) installed in the first installation track (14); The first end of the pawl (6) is rotatably connected to the middle rotating block (3), the second end of the pawl (6) is arranged counterclockwise relative to the first end of the pawl (6) and The second end of the ratchet (6) can engage with the internal teeth (501) of the ratchet. 2. The overrunning clutch according to claim 1, further comprising a spring (7) arranged between the intermediate rotating block (3) and the pawl (6). 3. The overrunning clutch according to claim 1 or 2, further comprising a connecting rod (8) and a nested chuck (9) rotatably connected to the connecting rod (8); The nested chuck (9) is rotatably connected to the second cover plate (4); A first groove (301) is opened on the middle rotating block (3); The connecting rod (8) swings in the first groove (301), and the first end of the connecting rod (8) is connected with the nested chuck (9), and the connecting rod (8) The second end is connected with the pawl (6); When the connecting rod (8) swings in the first groove (301), it can drive the pawl (6) to engage and separate from the internal teeth (501) of the ratchet. 4. The overrunning clutch according to claim 3, characterized in that a second groove (302) is opened on the middle rotating block (3), and the first groove (301) and the second groove (302) ) connected; The nested chuck (9) is provided with an arc-shaped protrusion (901), and the arc-shaped protrusion (901) can rotate in the second groove (302). 5. The overrunning clutch according to claim 4, further comprising a pawl control chuck (10); The pawl control chuck (10) is connected with the nested chuck (9). 6. The overrunning clutch according to claim 5, further comprising a pawl control lever (11); The pawl control rod (11) is arranged on the pawl control chuck (10). 7. The overrunning clutch according to claim 6, characterized in that, the pawl control lever (11) is arranged on the edge of the pawl control chuck (10). 8. The overrunning clutch according to claim 1, characterized in that a tripod (12) is provided at the end of the operating rod (1); The tripod (12) includes three support rods (1201), and the first bolt holes are provided on the support rods (1201), and the three support rods (1201) and the first cover plate (2) The threaded holes of the two cylinders (202) are connected with the threaded holes by screws. 9. The overrunning clutch according to claim 8, characterized in that, the operating rod (1) is a hollow structure with reinforcing ribs inside, the three support rods (1201) are distributed at 120 degrees, and each of the The support rod (1201) is provided with a second bolt hole connected with the first cover plate (2). 10. The overrunning clutch according to claim 1, characterized in that a second cover for supporting the ball (13) is provided on the first cover (2) and the second cover (4). Install the track.