CN108488332B

CN108488332B - Variable speed drive

Info

Publication number: CN108488332B
Application number: CN201810623091.2A
Authority: CN
Inventors: 姜新兵
Original assignee: Individual
Current assignee: Individual
Priority date: 2018-06-15
Filing date: 2018-06-15
Publication date: 2024-04-19
Anticipated expiration: 2038-06-15
Also published as: CN108488332A

Abstract

The invention discloses a variable speed transmission device, relates to the field of transmission devices, and aims to solve the problem that the transmission ratio difference of a traditional continuously variable transmission is difficult to achieve maximization. The technical scheme is characterized by comprising a plurality of transmission balls, an input ring and an output ring which are linked with the transmission balls, a positioning shaft which enables the transmission balls to rotate around the transmission balls, and an adjusting ring which is used for controlling the positioning shaft to swing, wherein in an initial state, the input ring is contacted with the transmission balls at the maximum rotation radius. The invention achieves the advantage of improving the adjustment range of the variable transmission ratio.

Description

Variable speed drive

Technical Field

The present invention relates to the field of transmissions, and more particularly to a variable speed transmission.

Background

The speed-changing transmission device is suitable for various fields of mechanical equipment, bicycles, electric vehicles, automobiles and the like, wherein the speed-changing transmission device of the bicycle changes the speed of the bicycle by changing the cooperation of chains and gear plates with different front and rear sizes.

The continuously variable star wheel transmission eliminates the traditional way of shifting the chain from one gear to another, by two rotating disks and a set of balls between them.

The prior Chinese patent with publication number CN107191565A discloses a stepless speed changer, which consists of a speed changer shell, a speed changer end cover, a main shaft, a flywheel, a power input assembly, a steel ball assembly, a power output assembly, an input stator, an output stator, a cylindrical gear and an eccentric gear, wherein the steel ball assembly consists of a steel ball and a pin, the steel ball can rotate by taking the pin as an axis, the steel ball assembly is arranged between an input traction ring and an output traction ring in pairs, and the steel ball assembly can swing to form an included angle with the axis direction of the main shaft.

As shown in fig. 1a and 1b of the specification, when the continuously variable transmission is in an initial state, i.e. the pins are parallel to the main shaft, at this time, the rotation radius of the input traction ring and the output traction ring (the rotation radius is the vertical length of the contact point of the input traction ring or the output traction ring and the steel ball from the pin axis) is the same, and the rotation angular speed of the steel ball is the same, then the rotation speeds of the input traction ring and the output traction ring are the same, and at this time, the transmission ratio of the continuously variable transmission is 1:1.

After the pin swings, an included angle is formed between the axis of the pin and the axis of the main shaft, so that the rotation radiuses of the input traction ring and the output traction ring are different, and the rotation speed difference of the input traction ring and the output traction ring is realized based on different linear speeds of the rotation radiuses on the ball body. Continuously variable transmissions are based on the above-described principles for achieving ratio adjustments.

However, in the process of swinging the pin, the pin is limited by a mechanical structure and the swinging distance of the steel ball, so that the transmission ratio difference of the continuously variable transmission is difficult to realize maximization.

Disclosure of Invention

In view of the shortcomings of the prior art, it is an object of the present invention to provide a variable speed transmission having the advantage of increasing the range of ratio adjustments.

In order to achieve the above purpose, the present invention provides the following technical solutions:

The variable speed transmission device comprises a plurality of transmission balls, an input ring and an output ring which are linked with the transmission balls, a positioning shaft which enables the transmission balls to rotate around the positioning shaft and an adjusting ring which is used for controlling the positioning shaft to swing, wherein the input ring and the output ring are positioned on the same side of the transmission balls, and in an initial state, the input ring is contacted with the transmission balls at the maximum rotation radius.

By adopting the technical scheme, the input ring and the output ring are positioned on the same side of the transmission ball, so that in an initial state, the input ring can be contacted with the maximum rotation radius of the transmission ball, and under the condition that the rotation angular speed of the transmission ball is fixed, the input ring can obtain the maximum rotation speed at the moment; in the initial state, the output ring is contacted with the minimum rotation radius of the transmission ball (the minimum rotation radius is the minimum rotation radius which can be actually achieved by the output ring and is not the minimum rotation radius of the transmission ball in theory, but the minimum rotation radius which can be actually achieved by the output ring is infinitely close to the minimum rotation radius of the transmission ball in theory), so that the rotating speed of the output ring is minimum at the moment; furthermore, in the initial state, the variable transmission device can obtain the maximum transmission ratio, and the maximum rotation ratio of the variable transmission device is larger than that of the continuously variable transmission in the background art, so that the invention has the advantage of increasing the adjustment range of the variable transmission ratio.

Further, a first inclined surface which is in contact with the transmission ball is arranged on the output ring.

Through adopting above-mentioned technical scheme, first inclined plane and driving ball contact, on the one hand can make the radius of rotation of output ring when initial state infinitely close to the minimum radius of rotation in driving ball theory, on the other hand can reduce the wearing and tearing to the driving ball, and then the life of extension driving ball.

Further, the input ring and the output ring are arranged in parallel.

By adopting the technical scheme, the input ring and the output ring are arranged in parallel, so that the structure of the speed changing device can be simplified, and the volume of the speed changing transmission device is further reduced.

Further, a first supporting ring which is contacted with the transmission ball is arranged on one side of the transmission ball away from the input ring.

Through adopting above-mentioned technical scheme, first support ring and input ring and output ring cooperation form three-point support to the driving ball, and then can increase driving ball pivoted stability.

Further, a second inclined surface which is in contact with the transmission ball is arranged on the first supporting ring.

Through adopting above-mentioned technical scheme, first support ring passes through the contact of second oblique face with the driving ball, can increase the stability that first support ring contacted with the driving ball on the one hand, on the other hand can reduce the wearing and tearing to the driving ball to the life of extension driving ball.

Further, a second supporting ring contacted with the transmission ball is arranged on one side, far away from the input ring, of the transmission ball, and the first supporting ring and the second supporting ring are arranged in parallel.

Through adopting above-mentioned technical scheme, the second support ring can further increase the supporting role to the driving ball with the driving ball contact, and then can increase the stability of driving ball.

Further, a third inclined surface which is contacted with the transmission ball is arranged on the second supporting ring.

Through adopting above-mentioned technical scheme, the second support ring passes through the third inclined plane and contacts with the driving ball, can increase the stability that the second support ring contacted with the driving ball on the one hand, on the other hand can reduce the wearing and tearing to the driving ball to the life of extension driving ball.

Further, one end of the input ring, which is far away from the transmission ball, is connected with an input snap ring, an input shaft sleeve is arranged in the middle of the input snap ring in a penetrating manner, and one end of the input shaft sleeve, which is far away from the input snap ring, is sleeved with an input flywheel.

Through adopting above-mentioned technical scheme, the input flywheel is through input axle sleeve and input snap ring and input ring linkage, then through the rotatory input flywheel of chain, can drive the input ring rotation to realize power input.

Further, the input snap ring comprises an input branch ring sleeved on the input shaft sleeve and input clamping blocks uniformly distributed on the outer side wall of the input branch ring, and a plurality of input clamping grooves matched with the input clamping blocks are uniformly distributed on the input ring.

By adopting the technical scheme, the input clamping block is embedded in the input clamping groove, so that the input branch ring and the input ring are linked, the input branch ring is sleeved on the input shaft sleeve, and the input shaft sleeve, the input clamping ring and the input ring are linked, so that the power input can be conveniently realized; meanwhile, the input clamping ring is connected with the input ring in a clamping way, so that the input ring can be conveniently replaced and overhauled.

Further, a plurality of limiting blocks are uniformly distributed on the inner side wall of the input branch ring, and a plurality of limiting grooves matched with the limiting blocks are uniformly distributed on the outer side wall of the input shaft sleeve.

Through adopting above-mentioned technical scheme, stopper and spacing groove cooperation can prevent to input branch ring and input axle sleeve relative rotation, and then can increase the stability of input axle sleeve and input snap ring linkage to can realize stable power input.

In summary, the invention has the following beneficial effects:

1. the input ring and the output ring are positioned on the same side of the transmission ball and are contacted with the maximum rotation radius of the transmission ball in the initial state, so that the effect of increasing the adjustment range of the speed change transmission ratio is generated;

2. The first inclined surface, the second inclined surface and the third inclined surface are adopted, so that the service life of the transmission ball is prolonged;

3. the limiting block and the limiting groove are adopted, so that the effect of improving the stability of power input is achieved.

Drawings

FIG. 1a is a schematic diagram of a transmission of a continuously variable transmission in the background art;

FIG. 1b is a schematic diagram of a transmission of a continuously variable transmission according to the background art;

FIG. 2a is a schematic diagram of a transmission of a variable speed drive in an embodiment;

FIG. 2b is a schematic diagram of the transmission of the variable speed drive of the embodiment;

FIG. 3 is a cross-sectional view of a variable speed drive of an embodiment;

FIG. 4 is an exploded view of the input ring, input collar and input sleeve of the embodiment;

FIG. 5 is a schematic explosion diagram of the adjusting ring, the first fixing ring, the driving ball and the second fixing ring according to the first embodiment;

FIG. 6 is a second schematic explosion diagram of the adjusting ring, the first fixing ring, the driving ball and the second fixing ring according to the embodiment;

FIG. 7 is an exploded view of the adjustment assembly and adjustment ring of the embodiment;

Fig. 8 is a schematic diagram showing the overall structure of the variable speed transmission device in the embodiment.

In the figure: 1. a drive ball; 11. positioning a shaft; 12. a centering hole; 2. a first retaining ring; 21. a first ball groove; 22. a slip hole; 23. a first protrusion; 24. a relief hole; 25. a fixing pin; 26. a first sleeve; 27. a clamping groove; 3. a second stator ring; 31. a second ball groove; 32. a slip groove; 33. a second protrusion; 34. a third protrusion; 35. a fixing groove; 36. a second sleeve; 4. an input ring; 41. inputting a clamping ring; 411. an input branch ring; 412. inputting a clamping block; 413. a limiting block; 42. inputting a clamping groove; 43. an input shaft sleeve; 431. a limit groove; 44. inputting a flywheel; 45. a third planar bearing; 5. an output ring; 51. a first oblique surface; 52. an output branch ring; 521. steel balls; 53. outputting a clamping ring; 6. an adjustment assembly; 61. an active shifting plate; 611. a drive ring; 612. an active support plate; 613. an active clamping plate; 62. a driven shifting plate; 621. a slave ring; 622. a driven support plate; 623. a driven groove; 624. a driven clamping plate; 625. a spline hole; 7. an adjusting ring; 71. an adjustment tank; 72. a fourth protrusion; 73. an adjusting ring plate; 74. a third sleeve; 741. a gear spline; 75. a first planar bearing; 76. a first support ring; 761. a second oblique surface; 77. a second planar bearing; 78. a second support ring; 781. a third inclined surface; 8. a main shaft; 81. a first auxiliary ring; 9. an output sleeve; 91. an output collar; 92. a first closed loop; 93. a second closed loop; 94. a traction ring; 95. traction holes.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings.

The present embodiment is only for explanation of the present invention and is not to be construed as limiting the present invention, and modifications to the present embodiment, which may not creatively contribute to the present invention as required by those skilled in the art after reading the present specification, are all protected by patent laws within the scope of claims of the present invention.

Examples:

The principle of the variable speed transmission device is as shown in fig. 2a and 2b, the input ring and the output ring are positioned on the same side of the transmission ball, and in the initial state, the contact point of the input ring or the output ring and the transmission ball is arranged at the position with the maximum rotation radius of the transmission ball. From the assembly perspective, the structure can effectively ensure that the transmission ratio of the variable transmission device reaches the maximum difference value, and further can increase the adjustment range of the variable transmission ratio.

Specifically, referring to fig. 3, the variable speed transmission device includes a transmission ball 1, and an input ring 4 and an output ring 5 that are linked with the transmission ball 1, in this embodiment, the input ring 4 and the output ring 5 are located on the same side of the transmission ball 1, and the input ring 4 is disposed in parallel on the inner periphery of the output ring 5.

Referring to fig. 3, a positioning shaft 11 is penetrated in the middle of the driving ball 1, and the driving ball 1 can rotate around the positioning shaft 11; a centering hole 12 for the positioning shaft 11 to pass through is arranged in the middle of the transmission ball 1, and a bearing (not shown in the drawing) embedded in the centering hole 12 is sleeved on the positioning shaft 11; both ends of the centering hole 12 and both ends of the positioning shaft 11 are round corners.

Referring to fig. 3, when the axial direction of the positioning shaft 11 is perpendicular to the axial direction of the main shaft 8, the initial state of the speed change transmission device is the initial state in which the input ring 4 is in contact with the maximum rotation radius of the transmission ball 1; the output ring 5 is provided with a first inclined surface 51 which is contacted with the transmission ball 1, so that in an initial state, the output ring 5 is contacted with the minimum rotation radius of the transmission ball 1; this minimum radius of rotation is the minimum radius of rotation that the output ring 5 can actually achieve, rather than the theoretical minimum radius of rotation of the drive ball 1, but the minimum radius of rotation that the output ring 5 can actually achieve is infinitely close to the theoretical minimum radius of rotation of the drive ball 1.

Referring to fig. 3, an input snap ring 41 is connected to one end of the input ring 4 away from the driving ball 1, and an input shaft sleeve 43 is arranged in the middle of the input snap ring 41 in a penetrating manner; an input flywheel 44 is sleeved at one end of the input shaft sleeve 43 far away from the input clamping ring 41, and two bearings sleeved on the main shaft 8 are embedded in the inner wall of the input shaft sleeve 43; in this embodiment, the input flywheel 44 cooperates with the chain to realize power input, and may also be realized by a synchronous belt or the like.

Referring to fig. 3, an output branch ring 52 is disposed at one end of the output ring 5 away from the driving ball 1, a plurality of steel balls 521 are embedded between the output branch ring 52 and the output ring 5, and the steel balls 521 are simultaneously embedded in a steel ball retainer (not shown in the drawing) sleeved on the input ring 4, so that the output ring 5, the steel balls 521, the steel ball retainer and the output branch ring 52 form a planar bearing, and further an axial limiting effect on the output ring 5 can be achieved.

Referring to fig. 3, the end surface of the adjusting ring plate 73 opposite to the driving ball 1 is provided with a first plane bearing 75, the first plane bearing 75 is connected with a first supporting ring 76 contacting the driving ball 1, and the first supporting ring 76 is provided with a second inclined surface 761 contacting the driving ball 1; the end of the first plane bearing 75 far away from the adjusting ring plate 73 is connected with a second plane bearing 77, the second plane bearing 77 is connected with a second supporting ring 78 contacted with the driving ball 1, and the second supporting ring 78 is provided with a third inclined surface 781 contacted with the driving ball 1.

Referring to fig. 3, an output clamping ring 53 is extended from the outer wall of the output ring 5, and the output clamping ring 53 is connected with an output sleeve 9; the output sleeve 9 comprises an output sleeve ring 91 connected with the output ring 5, and a first closed loop 92 and a second closed loop 93 respectively connected with two ends of the output sleeve ring 91; the outer wall of the output collar 91 is symmetrically connected with traction rings 94, a plurality of traction holes 95 are uniformly distributed on the traction rings 94, and the traction holes 95 on the two traction rings 94 are staggered; in the embodiment, the traction ring 94 is matched with the bus bar to realize power output, and the power output can also be realized by means of synchronous belt and gear transmission; in this embodiment, the output collar 53 is connected to the output collar 91 through a ratchet assembly (not shown in the drawing), so that the power output direction can be kept consistent.

Referring to fig. 3, the bearing sleeved on the third shaft sleeve 74 is embedded on the inner wall of the first closed loop 92, and the bearing sleeved on the input shaft sleeve 43 is embedded on the inner wall of the second closed loop 93, so that the output sleeve 9 can rotate relative to the main shaft 8, thereby realizing power output; a framework oil seal ring sleeved on the input shaft sleeve 43 is further arranged between the input shaft sleeve 43 and the second closed loop 93, so that the tightness of the output sleeve 9 can be improved; the third plane bearing 45 is disposed between the input snap ring 41 and the second closed ring 93, so that the axial limiting effect on the input ring 4 can be increased.

Referring to fig. 4, the input clamping ring 41 includes an input supporting ring 411 fixedly sleeved on the input shaft sleeve 43, six input clamping blocks 412 are uniformly distributed on the outer wall of the input supporting ring 411, and an input clamping groove 42 matched with the input clamping blocks 412 is formed on the input ring 4, so that the input clamping blocks 412 are matched with the input clamping grooves 42 to realize linkage between the input clamping ring 41 and the input ring 4; six limiting blocks 413 are uniformly distributed on the inner wall of the input support ring 411, limiting grooves 431 matched with the limiting blocks 413 are formed in the outer wall of the input shaft sleeve 43, and the limiting blocks 413 are matched with the limiting grooves 431, so that the linkage stability of the input clamping ring 41 and the input shaft sleeve 43 can be improved.

Referring to fig. 5, the device comprises a main shaft 8, wherein an adjusting ring 7, a first fixed ring 2 and a second fixed ring 3 are sleeved on the main shaft 8; the driving balls 1 are embedded between the first fixed ring 2 and the second fixed ring 3, the number of the driving balls 1 is at least 3, and in this embodiment, the number of the driving balls 1 is 6.

Referring to fig. 5, the inner wall of the first fixing ring 2 is concavely provided with a first ball groove 21 matched with the driving ball 1, and then the outer wall of the first fixing ring 2 forms a first protrusion 23 opposite to the first ball groove 21; the outer wall of the second fixed ring 3 is concavely provided with a second ball groove 31 matched with the transmission ball 1, and then the inner wall of the second fixed ring 3 forms a second bulge 33 opposite to the second ball groove 31; the first ball groove 21 and the second ball groove 31 cooperate to cover the driving ball 1 therein, and the driving ball 1 cannot be separated.

Referring to fig. 5, a sliding hole 22 matched with the positioning shaft 11 is formed in the middle of the first ball groove 21 on the first fixed ring 2, a sliding groove 32 matched with the positioning shaft 11 is formed in the middle of the second ball groove 31 on the second fixed ring 3, and a third protrusion 34 matched with the sliding groove 32 is formed in the middle of the second protrusion 33; the sliding hole 22 is disposed opposite to the sliding groove 32, and the positioning shaft 11 can swing in the directions of the sliding hole 22 and the sliding groove 32, and the swing axis direction of the positioning shaft 11 is perpendicular to the axis direction of the main shaft 8.

Referring to fig. 5, the adjusting ring 7 is sleeved on the outer periphery of the first fixing ring 2, and the adjusting ring 7 can rotate relative to the first fixing ring 2, so that the inner wall of the adjusting ring 7 presents an arc-shaped surface matched with the first protrusion 23; an adjusting groove 71 matched with the positioning shaft 11 is formed in the inner wall of the adjusting ring 7, and a fourth protrusion 72 opposite to the adjusting groove 71 is formed on the outer wall of the adjusting ring 7; one end of the positioning shaft 11 is embedded in the sliding groove 32, and the other end of the positioning shaft passes through the sliding hole 22 and is embedded in the adjusting groove 71; the adjusting groove 71 is curved, and the adjusting ring 7 is rotated, and the positioning shaft 11 can swing in the directions of the sliding hole 22 and the sliding groove 32 by the driving action of the adjusting groove 71.

Referring to fig. 5, a first auxiliary ring 81 is protruded on the main shaft 8, a second sleeve 36 is extended in the middle of the second fixing ring 3 in a direction away from the first fixing ring 2, and the second sleeve 36 is fixedly sleeved on the first auxiliary ring 81.

Referring to fig. 6, a first shaft sleeve 26 is extended in a direction away from the second fixed ring 3 in the middle of the first fixed ring 2, and the first shaft sleeve 26 is fixedly sleeved on a first auxiliary ring 81; the adjusting ring 7 is provided with the adjusting ring plate 73 that extends away from the one end of first fixed ring 2, and the direction that is kept away from first fixed ring 2 extends in the middle of the adjusting ring plate 73 and is provided with the third axle sleeve 74, and the bearing of cover on main shaft 8 is inlayed to the third axle sleeve 74 inner wall, then the adjusting ring 7 can rotate around main shaft 8.

Referring to fig. 6 and 5, a clamping groove 27 matched with the second fixed ring 3 is formed in the first fixed ring 2, and the clamping groove 27 is communicated with the first ball groove 21; six fixing pins 25 are uniformly and convexly arranged on the end face of the first fixing ring 2, which is opposite to the second fixing ring 3, and a fixing groove 35 in interference fit with the fixing pins 25 is formed on the end face of the second fixing ring 3, which is opposite to the first fixing ring 2; the fixed pin 25 is kept away from the terminal surface of first fixed ring 2 and fixed slot 35 opening part all is the chamfer setting, and then can conveniently imbed fixed pin 25 in the fixed slot 35.

Referring to fig. 6 and 3, the first protrusion 23 is provided with a relief hole 24 that cooperates with the first support ring 76 and the second support ring 78, so that the first support ring 76 and the second support ring 78 can rotate relative to the first fixing ring 2.

Referring to fig. 7, a third sleeve 74 is connected to the adjustment assembly 6 for controlling the rotation of the adjustment ring 7, the adjustment assembly 6 including a driven dial plate 62 connected to the third sleeve 74 and a driving dial plate 61 connected to the main shaft 8; the driven shifting plate 62 comprises a driven ring 621 fixedly sleeved on a third shaft sleeve 74, and a driven support plate 622 is arranged on the outer wall of the driven ring 621 in an extending manner; a driven groove 623 is formed in the middle of the driven support plate 622, and driven clamping plates 624 perpendicular to the driven support plate 622 are symmetrically arranged on the inner wall of the driven groove 623; the outer wall of the third shaft sleeve 74 is provided with a gear spline 741, a spline hole 625 matched with the gear spline 741 is formed in the middle of the driven ring 621, and then the gear spline 741 and the spline hole 625 are matched to increase the linkage stability of the driven shifting plate 62 and the adjusting ring 7.

Referring to fig. 7, the driving dial 61 includes a driving ring 611 sleeved on the main shaft 8, and the driving ring 611 can rotate around the main shaft 8; an active support plate 612 is arranged on the outer wall of the active ring 611 in an extending mode, and the active support plate 612 is vertically connected with an active clamping plate 613; the driving ring 611 is rotated, the driving clamping plate 613 can be contacted with the driven clamping plate 624, and the driving shifting plate 61 can control the driven shifting plate 62 to rotate, so that the adjusting ring 7 is controlled to rotate.

Referring to fig. 8, the adjustment assembly 6 and the input flywheel 44 are located outside the output sleeve 9, and the remaining assemblies are located inside the output sleeve 9, and the protection of the output sleeve 9 allows the transmission to be maintenance free.

The working principle is as follows:

the input ring 4 and the output ring 5 are arranged on the same side of the transmission ball 1 in parallel, in an initial state, the input ring 4 is in contact with the maximum rotation radius of the transmission ball 1, and under the condition that the rotation angular speed of the transmission ball 1 is fixed, the input ring 4 can obtain the maximum rotation speed at the moment;

in the initial state, the output ring 5 is in contact with the minimum rotation radius of the driving ball 1 (the minimum rotation radius is the minimum rotation radius which can be actually achieved by the output ring 5 instead of the theoretical minimum rotation radius of the driving ball 1, but the minimum rotation radius which can be actually achieved by the output ring 5 is infinitely close to the theoretical minimum rotation radius of the driving ball 1), so that the rotating speed of the output ring 5 is minimum at the moment;

furthermore, in the initial state, the variable transmission device can obtain the maximum transmission ratio, and the maximum rotation ratio of the variable transmission device is larger than that of the continuously variable transmission in the background art, so that the invention has the advantage of increasing the adjustment range of the variable transmission ratio.

Claims

1. A variable speed transmission device, comprising a plurality of transmission balls (1), an input ring (4) and an output ring (5) which are linked with the transmission balls (1), a positioning shaft (11) which enables the transmission balls (1) to rotate around the positioning shaft, and an adjusting ring (7) for controlling the positioning shaft (11) to swing, and the variable speed transmission device is characterized in that: the input ring (4) and the output ring (5) are positioned on the same side of the transmission ball (1), and in an initial state, the input ring (4) is in contact with the maximum rotation radius of the transmission ball (1);

the output ring (5) is provided with a first inclined surface (51) which is contacted with the transmission ball (1);

The speed change transmission device also comprises a main shaft (8), wherein an adjusting ring (7), a first fixed ring (2) and a second fixed ring (3) are sleeved on the main shaft (8), and the transmission ball (1) is embedded between the first fixed ring (2) and the second fixed ring (3);

the inner wall of the first fixed ring (2) is provided with a first ball groove (21) matched with the transmission ball (1) in an outward concave manner, and then the outer wall of the first fixed ring (2) forms a first bulge (23) opposite to the first ball groove (21); the outer wall of the second fixed ring (3) is concavely provided with a second ball groove (31) matched with the transmission ball (1), and then the inner wall of the second fixed ring (3) forms a second bulge (33) opposite to the second ball groove (31);

A sliding hole (22) matched with the positioning shaft (11) is formed in the middle of the first ball groove (21) on the first fixed ring (2), a sliding groove (32) matched with the positioning shaft (11) is formed in the middle of the second ball groove (31) on the second fixed ring (3), and a third protrusion (34) matched with the sliding groove (32) is formed in the middle of the second protrusion (33); the sliding hole (22) and the sliding groove (32) are arranged oppositely, the positioning shaft (11) can swing along the directions of the sliding hole (22) and the sliding groove (32), and the swinging axis direction of the positioning shaft (11) is perpendicular to the axis direction of the main shaft (8).

2. A variable speed drive as claimed in claim 1, wherein: the input ring (4) and the output ring (5) are arranged in parallel.

3. A variable speed drive as claimed in any one of claims 1 to 2, wherein: a first support ring (76) which is in contact with the transmission ball (1) is arranged on one side, away from the input ring (4), of the transmission ball (1).

4. A variable speed drive as claimed in claim 3, wherein: the first support ring (76) is provided with a second inclined surface (761) which is contacted with the transmission ball (1).

5. A variable speed drive as claimed in claim 3, wherein: the transmission ball (1) is provided with a second support ring (78) which is contacted with the transmission ball (1) on one side far away from the input ring (4), and the first support ring (76) and the second support ring (78) are arranged in parallel.

6. A variable speed drive as claimed in claim 5, wherein: the second support ring (78) is provided with a third inclined surface (781) which is contacted with the transmission ball (1).

7. A variable speed drive as claimed in any one of claims 1 to 2, wherein: one end of the input ring (4) far away from the transmission ball (1) is connected with an input clamping ring (41), an input shaft sleeve (43) is arranged in the middle of the input clamping ring (41) in a penetrating mode, and one end of the input shaft sleeve (43) far away from the input clamping ring (41) is sleeved with an input flywheel (44).

8. The variable speed drive of claim 7, wherein: the input clamping ring (41) comprises an input branch ring (411) sleeved on the input shaft sleeve (43) and input clamping blocks (412) uniformly distributed on the outer side wall of the input branch ring (411), and a plurality of input clamping grooves (42) matched with the input clamping blocks (412) are uniformly distributed on the input ring (4).

9. The variable speed drive of claim 8, wherein: the inner side wall of the input branch ring (411) is uniformly provided with

A plurality of limiting blocks (413), a plurality of limiting grooves (431) matched with the limiting blocks (413) are uniformly distributed on the outer side wall of the input shaft sleeve (43).