Plane braking device for electric winches and electric winch

The present invention discloses a plane braking device for electric winches and electric winch which disposes a section of hollow gear shaft, a section of core shaft, a fixing ring, a wedge shape support, a stopping piece, a braking plate, an elastic element, a wedge shape piece B, a wedge shape piece A, a braking clutch base and so on in a gear box of an electric winch. When a motor works, the section of core shaft of the motor drives the braking clutch base and the wedge shape pieces A, B to rotate, until a gap is formed between the adjacent braking plate and stopping piece between the braking clutch base and the wedge shape piece B, so that the braking effect disappears. When the motor stops suddenly, a heavy load lifted by a tight wire drum provides a reverse pulling force so that the wedge shape piece B produces a reverse thrust force to push the friction planes of the braking plate and the stopping piece, so the plane braking effect is achieved quickly. Based on the plane braking plate, the present invention can increase the braking area and the braking force and achieve safe braking. Furthermore, when there is wear of parts in long usage, so it only needs to replace the braking plate made of friction materials, which can simplify maintenance, reduce the parts costs and ensure service life of the gear box.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a braking device and electric winch, and more particularly to a plane braking device for electric winches and electric winch.

2. Description of the Prior Art

Electric brakes pull goods via reeling tight wire rope for self-aid and buddy aid in automobile accidents in the fields. For avoiding stall of tight wire rope caused by sudden power cut during retracting, braking devices are disposed for ensuring safe operation. A braking device for power winches disclosed in Chinese Patent Publish No. CN2484297Y includes a gear box, a braking cover, a section of gear shaft, a section of core shaft extending from a motor shaft, a wedge shape piece A, a wedge shape piece B, a braking clutch base, an elastic element, a brake plate and so on. The braking device uses the section of core shaft extending from the motor shaft to drive the braking clutch base to rotate. Inner double flanges in the braking clutch base simultaneously drive the wedge shape piece A and the wedge shape piece B to rotate. At this time, the braking plate on the wedge shape piece B and a friction tapered face of the gear box still keep a gap therebetween, so the braking device is in a non-braking state. When the motor suddenly stops, the inertia of the braking clutch base causes that the wedge shape piece B moves axially while rotating to drive the braking plate to achieve the single tapered face braking for the gear box. However, the braking device has the shortcomings that the braking area and the braking force produced by the single tapered face braking is small, slipping phenomena are easy to occur, and the braking plate directly acts on the tapered face of the gear box, which will easily make the tapered face to be wearing directly, so that the tapered face lose braking efficacy and the gear box must be replaced, which causes that the difficult maintenance and high replacement cost of parts.

This kind of present electric winch usually includes left and right support racks, a drum, a rotating shaft, a connecting shaft, a braking device disposed on the connecting shaft, a clutch device disposed on the rotating shaft and so on. A motor transfers power to the connecting shaft and the rotating shaft and drives the drum to rotate backward or forward via shaft teeth and planetary gears which engage with each other on the rotating shaft. The clutch device can control the motor shaft to transfer power to the drum. The braking device controls the connecting shaft to stop or rotate, thereby improving operation security and usage convenience. The present electric winch can have not only an effect of rapid clutch but also an effect of rapid braking, which is convenient for use. However, the electric winch still has a lot of structure shortcomings, for example, the braking device has structure performance not good enough and generally achieves a braking effect based on hard friction between metals, which causes that the parts are easy to be worn, so the braking device has a short service life and bad stability and operation security; and the parts of the clutch device have a complicated manufacturing process, which increases the manufacture costs.

SUMMARY OF THE INVENTION

An object of the present invention is to provide a plane braking device for electric winches and electric winch, wherein the plane braking device has a large braking area, good braking effects and low replacement cost of parts and avoids wearing the gear box directly, and the electric winch has the advantages of good structure performance, stable working performance, good operation security, simple manufacturing process, low manufacture costs and a long service life.

To achieve the above-mentioned object, a plane braking device for an electric winch and electric winch in accordance with the present invention is disclosed.

A plane braking device for electric winches includes: a gear box fixed on an electric winch; a braking cover fixedly connected with the gear box; a section of hollow gear shaft inserted in a shaft hole of the gear box and supported by a bearing; a section of core shaft extending from a motor shaft and passing through the hollow gear shaft, wherein one extended end portion of the core shaft which extends out of the hollow gear shaft is a polyhedron; a wedge shape piece A setting the hollow gear shaft and engaging with the hollow gear shaft, wherein a left end face of the wedge shape piece A is a cam face formed by double tapered faces, a right end face of the wedge shape piece A is limited axially by a C-ring, and an outer double flange structure is arranged with homogeneous distribution on the outer surface along an outer circumference face of the wedge shape piece A; a wedge shape piece B setting on the hollow gear shaft, wherein a right end face of the wedge shape piece B is a cam face formed by double tapered faces which engage with the wedge shape piece A, an outer double flange structure is arranged with homogeneous distribution on the outer surface along an outer circumference face of the wedge shape piece B; a plurality of braking plates; an elastic element bushing on the section of hollow gear shaft and abutting against the wedge shape piece B; a braking clutch base which has a center setting the end portion of the section of core shaft and combined with the polyhedron of the end portion, wherein a bearing supports between the braking clutch base and the braking cover, and an inner double flange structure is formed on an inner circumference face of the braking clutch base, matching to the outer double flange structures of the wedge shape piece A and the wedge shape piece B, to push the outer double flange structure of the wedge shape piece A to rotate thereby pushing the wedge shape piece B to move axially; a fixing ring closely disposed on an inner shoulder of the gear box; a wedge shape support setting on the section of hollow gear shaft; and a plurality of stopping pieces which is disposed between the wedge shape support and the wedge shape piece B and setting on the section of hollow gear shaft and engaged and drive-connected with the section of hollow gear shaft, the braking plates limited radially to rotate by a plurality of fixing ring and the elastic element are disposed between the stopping piece and the wedge shape piece B.

A plurality of extending sections axially extends from one end face of the fixing ring to form open slots arranged with homogeneous distribution on the outer surface along a circumference of the fixing ring, and the braking plates has keys arranged with homogeneous distribution on the outer surface on a circumference thereof and movably inserted in the open slots of the fixing ring.

The number of braking plates arranged axially is 4-6.

The wedge shape piece B has a ring groove formed in a left end face thereof for receiving the elastic element.

Comparing with the prior art, the present invention uses the friction braking of the multi-planes to replace the friction braking of the single tapered face, and there is no friction braking existing between the braking plates and the gear box. The optimal material selection for the wedge shape support, the stopping pieces and the wedge shape piece B can ensure that the friction wear faces concentrate in the braking plates and the braking area increases greatly, so the braking force increases and the braking is safer. Additionally, when the braking wear is serious, it only needs to replace the braking plates made of friction materials, which can simplify maintenance and reduce the costs greatly.

An electric winch includes left and right support racks; a drum disposed between the support racks and having two ends supported by bushings; a connecting shaft disposed in the drum and driven to rotate by a motor; a rotating shaft drive-connected with the connecting shaft and having a plurality of shaft teeth each of which engages with a corresponding planetary gear and drives the drum to rotate in clockwise and anticlockwise direction based on the rotation of the planetary gear inside the gear; a braking device which is disposed on the connecting shaft, a clutch device is disposed on the rotating shaft, wherein

a. The braking device includes a braking base which drive-connected with a motor shaft, wherein a wedge shape piece A and a wedge shape piece B are assembled in the braking base based on cam faces and driven to rotate by the braking base, internal teeth of the wedge shape piece A engage with external teeth of the connecting shaft, and on one adjacent side of the wedge shape piece B, a braking plate and a stopping piece, which are pushed to brake by a spiral spring, and the spiral spring is disposed between the wedge block B and the braking plate on the connecting shaft;

b. and the clutch device which includes a clutch base fixed on the support racks, wherein a bottom of the clutch base is a rising and falling protruding face which has blocking points disposed thereon; a clutch handle is disposed on the clutch base, and integral inserting feet extend from an end face of the handle; a rotation base is disposed in the clutch base and driven to rotate by the integral inserting feet of the handle; two symmetrical protruding blocks are disposed on an outer circumference face of the rotation base and pushed by the convex face of the clutch base and limited by the blocking points, and a C-ring II and a copper washer are disposed between the adjacent shaft teeth on the rotating shaft and fastened on the rotating shaft.

The plurality of shaft gear are third section shaft gear, second section shaft gear and first section shaft gear which drive-connected with the rotating shaft, which are setting on the rotating shaft, the corresponding first section shaft gear engage with first section planetary gears, the second section shaft gear engage with second section planetary gears, and the third section shaft gear engage with third section planetary gears; first grade transmission pieces are disposed between the first section planetary gears and the second section shaft gear, and second grade transmission pieces are disposed between the second section planetary gears and the third section shaft gear; and the third section planetary gears are disposed on the drum.

An axle bushing is disposed on the integral gear shafts of the drum, between the third section planetary gears and the drum.

A friction block is disposed between a bottom of the rotation base and an end portion of the rotating shaft.

Comparing with the prior art, the present invention uses the braking device and the clutch device with improved structures, wherein the clutch device uses the flexible braking plate and stopping piece and pushes the braking plate and the stopping piece to cling to each other based on the relative rotation of the wedge shape piece A and the wedge shape piece B of which the cam faces are engaged to each other, to achieve the braking effect, so the braking device can reduce wear of parts caused by hard friction, extend its service life; furthermore, besides ensuring good work stability and operation security of the clutch, the present invention only needs to turn the handle to push the rotating base and the rotating shaft to move axially so that the shaft teeth are detached from the planetary gears to achieve the clutch, which simplifies the manufacturing process and reduces manufacture costs effectively to meet the market requirements.

DETAILED DESCRIPTION OF THE INVENTION

The following is the detailed description of the embodiment of the present invention in connection with the appended drawings.

As shown inFIGS. 1-9, a plane braking device for electric winches according to the present invention includes a gear box4fixed on an electric winch, a braking cover13fixedly connected with the gear box4, and a section of hollow gear shaft2which extends into the center of the gear box4and is supported by a bearing3. The hollow gear shaft2has a multikey structure. A section of core shaft1extending from a motor shaft passes through the hollow gear shaft2, and one extended end portion of the core shaft1which extends out of the hollow gear shaft2is a hexahedron18. Besides the bearing3, a fixing ring20, a wedge shape support5, a braking plate6, a stopping piece21, an elastic element7, a wedge shape piece B8and a wedge shape piece A9are respectively disposed on the section of hollow gear shaft2from left to right.

The fixing ring20is closely disposed on the inner shoulder of the gear box4. Three extending sections, which are arranged with homogeneous distribution on the outer surface along the circumference of the fixing ring20, axially extend from one end face of the fixing ring20, thereby forming three open slots along the circumference in the fixing ring.

The wedge shape support5surrounds the section of hollow gear shaft2with gap thereof and the wedge shape support5is made of the wear resistant alloy steel.

The stopping piece21has an inner hole with a multikey structure. The stopping piece21sets on the second of hollow gear shaft2and engages with the second of hollow gear shaft2to establish a transmission relationship. The embodiment has one stopping piece, so it has two braking plates. Friction materials adhere to two sides of each metal piece which is used for manufacturing the braking plate, and are respectively disposed between the wedge shape support5and the stopping piece21and between the stopping piece21and the wedge shape piece B8, thereby forming four contacting friction surfaces. So the friction area increases, which further causes that a braking force increases. The number of the braking plate6can be increased or reduced according to power requirements. Each braking plate6has three keys arranged with homogeneous distribution on the outer surface on the circumference surface thereof. The keys can be movably inserted in the open slots of the fixing ring20so that the braking plates6are limited in the radial direction by the fixing ring20and can only rotate in a small space.

The elastic element7is a pagoda-shaped left-hand spring and disposed between the stopping piece21and the wedge shape piece B8which are made of wear resistant alloy steel, one end fastened in a hole of the section of hollow gear shaft2and the other end fastened in a hole of a ring groove17of the wedge shape piece B8. The elastic element7is convenient for pushing the wedge shape piece B when there is no need of braking, thereby relieving the thrust acting on the braking plates6and forming gaps between the braking plate and the stopping piece and between the braking plate and the wedge shape support (as shown inFIGS. 2-4). During assembly, the elastic element7is compressed, so there is a tendency to push the wedge shape piece B away so that the friction faces of the braking plates provide a gap. Accordingly, during assembly, it needs a proper turning force existing between the wedge shape piece B8and the elastic element7, that is, when the two ends of the elastic element7are respectively fastened in the holes, the wedge shape piece B8needs to have a proper reverse turning force relative to the elastic element7.

The section of hollow gear shaft2passes through a shaft hole of the wedge shape piece B8, and there is no direct transmission relation between the wedge shape piece B8and the section of hollow gear shaft2. An inner hole of the wedge shape piece A9is a splined gear hole which can engage with splined teeth of the section of hollow gear shaft2thereby forming a direct transmission relation therebetween, and at the same time, the wedge shape piece A9is axially limited by a group of C-shaped C-rings10which disposed on the hollow gear shaft2in order to limit and prevent the move of the wedge shape piece A. Combination end faces of the wedge shape piece B and the wedge shape piece A are cam faces16formed by double-inclined-faces. When the cam faces of the wedge shape piece B and the wedge shape piece A are combined with each other, the mechanism is in a non-braking state; and when the cam faces of the wedge shape piece B and the wedge block A, which are formed by double-inclined-faces, are detached from each other, the wedge shape piece A pushes the wedge shape piece B to move towards the left axially so that the mechanism is in a braking state where the mechanism abuts against the braking plates (as shown inFIGS. 6-8). Outer double flange structures15,14are respectively arranged with homogeneous distribution on the outer surface along the circumferences of the wedge shape piece A and the wedge shape piece B on the outer circumference faces of the wedge shape piece A and the wedge shape piece B.

A braking clutch base11has a center shaft hole which is a hexahedral hole. The braking clutch base11sets on the hexahedron18of the end portion of the section of core shaft1and has a direct driving relation with the section of core shaft1. The bearing12supports between the braking clutch base11and the braking cover13. The braking clutch base11has an inner double flange structure19arranged with homogeneous distribution on the outer surface along the circumference thereof (as shown inFIG. 3,FIG. 5,FIG. 7,FIG. 8), matching to the outer double flange structures of the wedge shape piece A and the wedge shape piece B. When the section of core shaft1is driven by a motor shaft, the braking clutch base11rotates (clockwise or anticlockwise), and the inner double flanges19in the braking clutch base11push the outer double flanges15of the wedge shape piece A9so that the wedge shape piece A rotates along with the braking clutch base11, thereby the section of hollow gear shaft can be driven to rotates synchronously by the wedge shape piece A. At the same time, the braking clutch base11immediately pushes the inner double flanges19to the outer double flanges14of the wedge shape piece B to drive the wedge shape piece B to rotate.

When a heavy load needs to be lifted, users can press a clockwise press button so that the motor core shaft rotates in clockwise direction. When the motor drives its core shaft to rotate, the braking clutch base is driven immediately and the inner double flanges in the braking clutch base are pushed to abut against the outer double flanges of the wedge shape piece A and the outer double flanges of the wedge shape piece B, so that the wedge shape pieces A, B can be synchronously driven to rotate (as shown inFIGS. 2-3). At this time, the wedge shape piece A drives the section of hollow gear shaft to rotate synchronously, so the section of hollow gear shaft engages with the above-mentioned deceleration gear group (not shown), thereby driving a tight wire drum to rotate to reel up a wire rope. Accordingly, the heavy load is lifted. At the same time, since the wedge shape piece B is also driven so that the angle difference between the wedge shape piece A and the wedge shape piece B disappears, the gentler cam inclined face of the wedge shape piece B is close to that of the wedge shape piece A (as shown inFIGS. 2-3), and the rotation force of the gentler cam inclined face is greater than a reverse twisting force on the wedge shape piece B, and besides, the reverse thrust force of the elastic element has an effect on the wedge shape piece B, the wedge shape piece B moves towards the right (as shown inFIG. 2andFIG. 4). Accordingly, the braking plates are detached from the friction faces, and the heavy load can be lifted successfully. When the motor stops transferring power, the motor core shaft and the braking clutch base thereupon stop rotating, so the inner double flanges19in the braking clutch base11stop pushing the outer double flanges14,15. At this time, a twisting force produced under the gravity of the heavy load pulls the tight wire drum to turn back through the wire rope and is transmitted to the core shaft1and the wedge shape piece A via the deceleration gear group so that the core shaft1and the wedge shape piece A are desired to turn back. In fact, the wedge shape piece A really turns back for a very small distance and then stops. So the angle difference between the wedge shape piece B and the wedge shape piece A instantly appears, and the steeper inclined face of the wedge shape piece A is pushed to that of the wedge shape piece B, and besides, the reverse twisting force of the elastic element has the effect on the wedge shape piece B, the wedge shape piece B has to move towards the left (as shown inFIG. 7andFIG. 8), thereby instantly producing a braking effect of contact friction of the braking plates and friction faces. Furthermore, the greater the twisting force of the heavy load is, the greater the push force that the wedge shape piece A exerts on the wedge shape piece B is, so the braking force produced by the contact friction is greater.

The braking effect produced in the process of lifting the heavy load to a higher position is described above. In another process that the heavy load is lowered from a higher position to a lower position, when the heavy load has been lifted to the end of the wire rope and hung in the air, the braking effect, which is described above and produced when the power is off, as shown inFIG. 7andFIG. 8, is firstly produced. Then users can operate the motor so that the motor rotates in anticlockwise direction, so the motor core shaft and the braking clutch base all rotate in anticlockwise direction. Instantly, the inner double flanges in the braking clutch base push the outer double flanges of the wedge shape piece B and the outer double flanges of the wedge shape piece A (as shown inFIGS. 4-5), so the angle difference between the wedge shape piece B and the wedge shape piece A disappears, and the gentler cam inclined face of the wedge shape piece B is close to that of the wedge shape piece A again (as shown inFIG. 4). Accordingly, the tapered face of the wedge shape piece B is detached from the friction faces of the braking plates, and the heavy load can be lowered successfully. ComparingFIG. 4withFIG. 5, when the heavy load is lifted and lowered under power, the wedge shape piece B always moves towards the right slightly and stops braking. When the motor stops, the braking effect as shown inFIG. 8is achieved quickly. Besides, there also exists the braking effect when the heavy load isn't lifted or lowered and the power is off.

Accordingly, the present invention has the braking effect after assembly. Once the motor works (in clockwise or anticlockwise direction), the braking effect disappears; and when the power is off or cut suddenly, the braking effect is instantly produced, and the heavier the heavy load is, the greater the braking force is, thereby ensuring safe and convenient use.

An electric winch includes two left and right support racks91, a drum93disposed between the two support racks91and having two ends supported by bushings, and a connecting shaft929disposed in the drum93and driven by a motor. The connecting shaft929is supported on a small bearing98and a braking device is disposed on the connecting shaft929to stop the connecting shaft929rotating. The braking device, as shown inFIG. 11andFIGS. 13-20, includes a cylindrical braking base931connected with a motor shaft933via key and groove engagement transmission. Two symmetrical protruding strips936are disposed on the inner wall of the braking base931. A wedge shape piece A4and a wedge shape piece B5are assembled in the braking base931, engaging with each other based on cam faces. Two symmetrical protruding shoulders937are formed on the outer circumference face of the wedge shape piece A, and the wedge shape piece B5also has two symmetrical protruding shoulders937formed on the outer circumference face thereof. After the wedge shape piece B5and the wedge shape piece A4are assembled based on the cam face, the protruding shoulders of the two wedge shape pieces are just collinear. When the wedge shape piece B5and the wedge shape piece A4are assembled into the braking base931, the protruding shoulders are driven by the protruding strips936of the braking base so that the wedge shape piece B5and the wedge shape piece A4rotate. The two wedge shape pieces also have inner hole structures, inner teeth formed on the inner hole wall of the wedge shape piece A4. On one adjacent side of the wedge shape piece B5, a braking plate96and a stopping piece97, which are pushed to brake by a spiral spring930, are disposed. The braking plate96and the stopping piece97are made of flexible materials in order to reduce mechanical wear of parts and improve braking stability during braking. The spiral spring930sets on the connecting shaft929and is disposed between the wedge shape piece B5and the braking plate96on the connecting shaft929. The connecting shaft929has external teeth939disposed on one end thereof, and the other end of the connecting shaft929has an inner hexagon structure. The end of the connecting shaft929with the external teeth939passes through the braking plate96, the stopping piece97, and the engaged wedge shape piece A4and wedge shape piece B5and then locks a pair of C-ring III932. Also, the connecting shaft929is driven to rotate by the wedge shape piece A4via the engagement of the external teeth939and the internal teeth938of the wedge shape piece A4.

The connecting shaft929is drive-connected with the rotating shaft928based on the inner hexagon structure. The structures of parts disposed on the rotating shaft928are shown inFIG. 12. Third section shaft gear926, second section shaft gear923and first section shaft teeth920are disposed on the rotating shaft928, the first section shaft gear920drive-connected with the rotating shaft928. A compression spring927sets on the rotating shaft928, two ends of the compression spring927respectively abutting against the connecting shaft929and the third section shaft gear926. The first section shaft gear920and the rotating shaft928establish a driving connection therebetween based on the inner hexagon structure. The first section shaft gear920also engage with first section planetary gears913and drive the first section planetary gears913to rotate. The first section planetary gears913are connected with the second section shaft gear923via first grade transmission pieces911; correspondingly, the second section shaft gear923engage with second section planetary gears912which are connected with the third section shaft gear926via second grade transmission pieces935, and the third section shaft gear926engage with third section planetary gears910. The first grade transmission pieces911and the second grade transmission pieces935have a rotating shaft power transmission function. Each transmission piece has a fixing piece921fixed thereon, and the fixing pieces of the third second planetary gears910are fixed on the drum93via small inner hexagona screws922. The third planetary gears910are further rotate three integral gear shafts940mounted on the end face of the drum93. An axle bushing99for avoiding rotation wear is disposed between the third section planetary gears910and the integral gear shafts940of the drum93, and the first section planetary gears913, the second section planetary gears912and the third section planetary gears910engage with internal teeth of the ring gear934at the same time. When the rotating shaft928rotates in clockwise or anticlockwise direction to drive the three third section planetary gears910to rotate in the ring gear934, the drum93can be drive to rotate in clockwise or anticlockwise direction.

A clutch device is disposed on the rotating shaft928, a clutch shaft engaging with the drum93. The clutch device, as shown inFIG. 21andFIG. 22, includes a clutch base915fixed on support rack91via large inner hexagon screws. The bottom of the clutch base915is a rising and falling protruding face943which has blocking points944respectively disposed on the highest point and the lowest point of the protruding face943. A clutch handle916, which can rotate manually, is disposed on the clutch base915. Three integral inserting feet941extend from the end face of the handle916. The inserting feet have C-ring I918fastened thereon to prevent the handle916being detached from the clutch base915. A rotation base919is disposed in the clutch base915, abutting against the protruding face943. The rotation base919is integrative with the integral inserting feet941of the handle916and driven to rotate by the integral inserting feet941of the handle916. Two symmetrical protruding blocks942are disposed on the outer circumference face of the rotation base919and pushed by the protruding face943of the clutch base915and limited by the rotation of blocking points944. The limitation way is that the protruding block just rises to the highest point of the whole protruding face943or falls to the lowest point of the whole protruding face943and is blocked to further rotate by the blocking points when the rotation base is driven by the handle916to rotate 150 degrees. A friction block917is disposed between the bottom of the rotation base919and the end portion of the rotating shaft928to reduce wear produced during relative rotation. Further, a C-ring II924and a copper washer925are fastened on the rotating shaft928between the second section shaft gear923and the third section shaft gear926. The rotation base919pushes the rotating shaft and further pushes the third section shaft gear926which the compression spring927has an effect on to move and be detached from the second grade transmission pieces935via the fastened C-ring II924, thereby clutching the engaged shaft gear and planetary gears and stopping the power transmission from the rotating shaft to the drum93.

During use of the present invention, the motor starts, and the forward and the backward motor shafts933drive the braking base931to rotate. The braking base931drives the wedge shape piece A4and the wedge shape piece B5disposed in the braking base to rotate. The wedge shape piece A4drives the connecting shaft929to rotate via the internal teeth938. The connecting shaft929drives the rotating shaft928and the first section shaft gear920on the rotating shaft928to rotate via the inner hexagon structure. At this time, after power enters the engaged first section shaft gear920and first section planetary gears913, power is transferred to the engaged second section shaft gear923and second section planetary gears912through the first grade transmission pieces911, and then transferred to the engaged third section shaft gear926and third section planetary gears910through the second grade transmission pieces935. The third section planetary gears910rotate around the ring gear934under function of power, while they can drive the drum93to rotate in clockwise or anticlockwise direction, thereby pulling goods via reeling wire rope on the drum93.

During the work process of the braking device, as shown inFIGS. 13-20, after the motor turns off, the inertia causes that the rotating wedge shape piece A4and the rotating wedge shape piece B5have different rotating speeds, so that the cam face of the wedge shape piece A4is detached from the engagement position of the cam face of the wedge shape piece B5, thereby pushing the wedge shape piece B5to press the braking plate96and the stopping piece97. When the braking plate96and the stopping piece97are closest to each other, the connecting shaft929, which can transfer power based on the engagement of the internal teeth and the external teeth, is locked, thereby achieving the braking effect.FIG. 13andFIG. 14are schematic views showing that the braking device is in the tightest braking state;FIG. 15andFIG. 16are schematic views showing positions of the wedge shape pieces A, B when the motor shaft rotates in anticlockwise direction; andFIG. 17andFIG. 18are schematic views showing positions of the wedge shape pieces A, B when the motor shaft rotates in clockwise direction. When restarting the motor, as shown inFIG. 19andFIG. 20, the cam faces of the wedge shape piece A4and the wedge shape piece B5return to the assembled positions, and under the action of elasticity of the spiral spring930, the plane of the wedge shape piece B5is pushed to be detached from the braking plate96and the stopping piece97, so the drum93can rotate in clockwise and anticlockwise direction, without braking.

During the work process of the clutch device, as shown inFIGS. 21-20, the clutch handle916is turned in clockwise direction to drive the rotation base919to rotate under the action of the integral inserting feet941of the handle916and drive the rotation base919to move axially under the action of the rising and falling protruding face943of the bottom of the clutch base915. When rotating to 150 degrees and limited by the blocking points944, the two protruding blocks of the rotating base are located on the highest point of the protruding face, and at this time, the displacement is the maximum displacement; after the rotation base moving axially pushes the rotating shaft to move, the rotation base also pushes the third section shaft teeth to overcome the elasticity of the compression spring927and move via the C-ring II924and the copper washer925fastened on the rotating shaft, so that the third section shaft teeth are detached from the second grade transmission pieces935and the power transmission is interrupted, and then the drum93can be turned manually. When escaping from the on-off state, the clutch handle is turned in anticlockwise direction to 150 degrees and limited by the blocking points, and under the action of the elasticity of the compression spring927, the third section shaft gear926reengage with the second grade transmission pieces935and the third section planetary gears910, the second section planetary gears912, and the first section planetary gears913return to the engagement positions, so the rotating shaft928transfers power to drive the drum93to rotate in clockwise and anticlockwise direction.