WO2019241922A1 - Drive device and speed reduction mechanism therefor - Google Patents

Abstract

Disclosed are a drive device and a speed reduction mechanism therefor. The speed reduction mechanism comprises a housing (11); an output gear (14) comprising several tooth spaces, wherein each tooth space comprises a first side face and a second side face opposite the first side face; a first transmission gear unit comprising a first tooth that engages with an input gear (13) and a second tooth that engages with the output gear (14); a second transmission gear unit comprising a third tooth that engages with the input gear (13) and a fourth tooth that engages with the output gear (14); and a force application component connected to the first transmission gear unit and/or the second transmission gear unit to provide a pre-tightening force between the gears, so that the second tooth maintains contact with a first side face of a tooth space engaging with the second tooth, and the fourth tooth maintains contact with a second side face of a tooth space engaging with the fourth tooth.

Description

Driving device and reduction mechanism Technical field

The invention relates to the technical field of deceleration driving, and more particularly, to a driving device and a deceleration mechanism thereof.

Background technique

The reduction mechanism is generally used for low-speed high-torque transmission equipment. It usually adopts gear transmission. It can achieve the power of the motor, internal combustion engine or other high-speed running power through the small gear on the input shaft of the reduction mechanism to mesh with the large gear on the output shaft. For the purpose of deceleration, when the meshing gap is generated due to the cooperation between gears and gears and the wear problem, which affects the smoothness and accuracy of the gear transmission, it is difficult for the existing reduction mechanism to achieve zero backlash. Backlash, the cost of time and production costs are relatively high. A driving device formed by connecting the reduction mechanism with a power mechanism such as an electric motor or an internal combustion engine has poor transmission stability, low transmission accuracy, and is prone to noise.

technical problem

The reduction mechanism is generally used for low-speed high-torque transmission equipment. It usually adopts gear transmission. It can achieve the power of the motor, internal combustion engine or other high-speed running power through the small gear on the input shaft of the reduction mechanism to mesh with the large gear on the output shaft. For the purpose of deceleration, when the meshing gap is generated due to the cooperation between gears and gears and the wear problem, which affects the smoothness and accuracy of the gear transmission, it is difficult for the existing reduction mechanism to achieve zero backlash. Backlash, the cost of time and production costs are relatively high. A driving device formed by connecting the reduction mechanism with a power mechanism such as an electric motor or an internal combustion engine has poor transmission stability, low transmission accuracy, and is prone to noise.

Technical solutions

The technical problem to be solved by the present invention is to provide an improved reduction mechanism;

The technical problem to be solved by the present invention is to provide an improved driving device.

The technical solution adopted by the present invention to solve its technical problems is to construct a reduction mechanism including a casing, and an input gear, a first transmission gear unit, a second transmission gear unit, an output gear, and an input gear provided in the casing. Force component

The output gear includes a plurality of coggings, and each cogging includes a first side surface and a second side surface opposite to the first side surface;

The first transmission gear unit is disposed between the input gear and the output gear; the first transmission gear unit includes a first tooth and a second tooth; the first tooth meshes with the input gear, so Said second tooth meshes with said output gear;

The second transmission gear unit is disposed between the input gear and the output gear, and the second transmission gear unit includes a third tooth and a fourth tooth; the third tooth meshes with the input gear, so The fourth tooth meshes with the output gear;

The force applying component provides a pre-tightening force for the input gear, the first transmission gear unit, the second transmission gear unit, and the output gear, so that the second tooth engages with the first side of the cogging groove. The fourth tooth is kept in contact with the second side of the tooth groove with which it is engaged.

Preferably, the first transmission gear unit includes a first transmission gear combination that meshes with the input gear; the first transmission gear combination is movably disposed in the housing in the axial direction; the first transmission gear combination The first gear includes a first gear, the input gear includes a first helical gear, the first gear meshes with the second helical gear, and the force applying component is combined with the first transmission gear, and Applying an axial force to the first transmission gear combination, the first helical gear and the second helical gear converting the axial force into a rotational force, driving an input gear, a first transmission gear unit, and a second transmission The pre-tension force is formed by the pressure between the gear unit and the output gear after the gear is rotated into position.

Preferably, the force applying component includes an elastic member provided on the first gear to apply pressure to drive the first transmission gear combination to move in the axial direction, and a bearing fixing the elastic member; one end of the elastic member The first gear is in contact with the first gear, and the other end is arranged in the bearing to generate an axial force. The helical teeth of the first gear convert the rotational force, which drives the input gear to rotate, so that the second gear The tooth is in contact with the first side of the tooth groove that is engaged with it, and the fourth tooth is in contact with the second side of the tooth groove that is engaged with it.

Preferably, the first transmission gear combination further includes a second gear; the second gear is fixedly connected to the first gear at one end of the first gear;

The second transmission gear unit includes a second transmission gear combination that meshes with the input gear; the second transmission gear combination includes a third gear and a fourth gear, and the fourth gear is disposed at the first One end of the three gears is fixedly connected with the first gear;

The third gear includes a third helical gear that meshes with the first helical gear.

Preferably, the first gear meshes with the input gear, and the second gear meshes with the output gear; the teeth on the first gear are the first teeth, and the teeth on the second gear Is the second tooth; the tooth on the third gear is the third tooth, and the tooth on the fourth gear is the fourth tooth.

Preferably, the first transmission gear unit further includes at least one other first transmission gear combination; the at least one other first transmission gear combination is disposed between the first transmission gear combination meshing with the input gear and the first transmission gear combination Between output gears;

The teeth on the first gear combination of the first transmission gear set adjacent to the input gear are the first teeth; the second gear of the first transmission gear combination set adjacent to the output gear is the second gear. The upper teeth are the second teeth;

The second transmission gear unit further includes at least one other second transmission gear combination; the at least one other second transmission gear combination is disposed between the second transmission gear combination meshing with the input gear and the output gear The teeth on the third gear combination of the second transmission gear set adjacent to the input gear are the third teeth; the fourth of the combination of the second transmission gear set adjacent to the output gear is the fourth The teeth on the gear are the fourth teeth.

Preferably, the output gear includes a first spur gear, and the second gear and the third gear each include a second spur gear that meshes with the output gear;

The diameter of the input gear is smaller than the diameter of the first gear and the third gear, and the diameter of the second gear and the fourth gear are smaller than the diameter of the first gear and the third gear; the output gear The diameter of is larger than the diameter of the second gear and the fourth gear.

Preferably, the housing includes a base and an end cover covering the base; a space is received between the base and the end cover; the motor is disposed at one end of the base and an output shaft thereof is from the base The base penetrates into the receiving space; the other end of the elastic member is in contact with the end cover.

Preferably, the axes of the first transmission gear combination and the second transmission gear combination are respectively disposed in parallel with the axis of the input gear; the axis of the input gear is disposed in parallel with the axis of the output gear; the first transmission The gear combination and the second transmission gear combination are respectively disposed on two opposite sides of the line connecting the axis of the input gear and the axis of the output gear;

The base is provided with a first fixed shaft, a second fixed shaft, and a third fixed shaft that extend toward the accommodation space and are arranged in parallel with each other; the output gear is fixed on the first fixed shaft;

The output gear is sleeved on the first fixed shaft;

The first transmission gear combination is sleeved on the second fixed shaft;

The second transmission gear combination is sleeved on the third fixed shaft;

The end cover is provided with a through hole through which the first fixed shaft passes.

The present invention also provides a driving device including a motor and a reduction mechanism according to the present invention. The motor is disposed at one end of the casing and an output shaft thereof is extended from the casing. The input gear is sleeved on the casing. The periphery of the output shaft.

Beneficial effect

The driving device and the reduction mechanism implementing the present invention have the following beneficial effects: the reduction mechanism engages the first tooth of the first transmission gear unit with the input gear, the second tooth engages with the output gear; The third tooth of the transmission gear unit meshes with the input gear, and the fourth tooth meshes with the output gear; and by connecting the force applying component with the first transmission gear unit and / or the second transmission gear unit, the input is The gear, the first transmission gear unit, the second transmission gear unit, and the output gear provide a pre-tightening force, so that the second tooth is kept in contact with the first side of the tooth groove that is engaged with it, and the fourth tooth is engaged with the first tooth The second side of the cogging remains in contact, so that the backlash between the input gear, the first transmission gear unit, the second transmission gear unit, and the output gear is zero, thereby improving the transmission stability and transmission accuracy of the reduction mechanism. degree.

The driving device can reduce the motor by connecting the input gear of the reduction mechanism of the present invention to the motor, and has the advantages of strong transmission stability and high transmission accuracy.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will be further described below with reference to the accompanying drawings and embodiments. In the drawings:

1 is a schematic structural diagram of a first embodiment of a driving device and a reduction mechanism of the present invention;

2 is a partial structural diagram of a first embodiment of a driving device and a reduction mechanism of the present invention;

3 is a schematic structural diagram of a reduction mechanism of a first embodiment of a driving device and a reduction mechanism of the present invention;

4 is a schematic structural diagram of an end cover of a first embodiment of a driving device and a reduction mechanism of the present invention;

5 is a schematic structural diagram of a reduction mechanism of a second embodiment of a driving device and a reduction mechanism of the present invention.

Best Mode of the Invention

In order to have a clearer understanding of the technical features, objects, and effects of the present invention, specific embodiments of the present invention will now be described in detail with reference to the drawings.

1 to 4 show a first preferred embodiment of the reduction mechanism of the present invention.

The reduction mechanism can be used for low-speed high-torque transmission equipment. It can reduce the output of electric motors, internal combustion engines or other high-speed running power. It has the characteristics of simple structure, low manufacturing cost, strong transmission stability, and high transmission accuracy.

As shown in FIG. 1 to FIG. 4, the reduction mechanism includes a casing 11, and an input gear 13, a first transmission gear unit, a second transmission gear unit, an output gear 14, and a force applying component provided in the casing 11; The casing 11 can be used to install the input gear 13, the first transmission gear unit, the second transmission gear unit, the output gear 14, and the force applying component. The input gear 13 can be sleeved on the periphery of the output shaft of the motor 12. The rotation of the motor 12 drives the rotation. One end of the first transmission gear unit is engaged with the input gear, and the other end is engaged with the output gear 14 to drive the input gear 13 to drive the output gear 14 to rotate; the first transmission gear unit and the second transmission Gear units are respectively disposed on both sides of the input gear and the output gear; one end of the second transmission gear unit is meshed with the input gear, and the other end is meshed with the output gear 14 so as to be driven by the input gear 13 and further The output gear 14 is driven to rotate. The output gear 14 is driven to rotate by the first transmission gear unit or the second transmission gear unit, thereby achieving deceleration output. The axes of the first transmission gear combination 15a and the second transmission gear combination 16a are respectively parallel to the axis of the input gear 13, the axis of the input gear 13 is parallel to the axis of the output gear 14, and the first transmission gear combination The combination with the second transmission gear is respectively disposed on two opposite sides where the axis of the input gear 13 and the axis of the output gear 14 are connected. The force applying component is connected to the first transmission gear unit and / or the second transmission gear unit. In this embodiment, it is connected to the first transmission gear unit; it may be the input gear 13 and the first transmission gear. The unit, the second transmission gear unit, and the output gear 14 provide a pre-tightening force, so that the backlash of the input gear 13, the first transmission gear unit, the second transmission gear unit, and the output gear 14 is zero.

As shown in FIGS. 2 and 4, the casing 11 includes a base 111 and an end cover 112; a receiving space may be formed between the base 111 and the end 112. The base 111 may be connected to a motor 12, and the motor 12 may be disposed at one end of the base 111 and an output shaft thereof may pass from the base 11 into a receiving space formed between the base 11 and the end 112. The end cover 112 can cover the base 111, and a through hole is provided on the end cover 112 for the fixed shaft of the input gear to pass through.

Further, the base 111 is provided with a first fixed shaft 1111, a second fixed shaft 1112, and a third fixed shaft 1113; the first fixed shaft 1111, the second fixed shaft 1112, and the third fixed shaft 1113 extend toward the accommodation space and The first fixed shaft 1111 and the base 111 are detachably connected in parallel with each other. The first fixed shaft 1111 is detachably connected to the through hole on the base 111. The output gear 14 is sleeved on the first fixed shaft 1111. The shaft 1111 can be rotated by the output gear 14. The second fixed shaft 1112 may be fixedly installed on the base 111, or may be detachably connected to the base 111. The number of the second fixed shaft 1112 is not limited, and may be one or multiple. The first The transmission gear combination is sleeved on the second fixed shaft 1112 and can be rotated on the second fixed shaft 1112. The third fixed shaft 1113 may be fixedly installed on the base 111, or may be detachably connected to the base 111. The number of the third fixed shaft 1113 is not limited, and it may be one or multiple; the second The transmission gear combination is sleeved on the third fixed shaft 1113 and can rotate on the third fixed shaft 1113.

As shown in FIGS. 2 and 3, the input gear 13 is sleeved around the output shaft of the motor 12. In this embodiment, it may be a first helical gear. It can be rotated by the motor 12 to drive rotation, which is equivalent to the rotation speed of the motor 12 to transmit the rotation speed of the motor 12 to the first transmission gear unit and the second transmission gear unit.

The size of the output gear 14 is larger than the size of the input gear 13, so its output speed is less than the speed of the motor 12. It can be driven by the first transmission gear unit or the second transmission gear unit to rotate, or it can drive the The second transmission gear unit or the first transmission gear unit rotates. When the motor 12 rotates, the input gear 13 rotates, which in turn drives the first transmission gear unit to rotate, thereby driving the output gear 14 to rotate, and finally drives the second transmission gear. The transmission gear unit rotates. Alternatively, when the motor 12 rotates, the input gear 13 rotates, thereby driving the second transmission gear unit to rotate, thereby driving the output gear 14 to rotate, and finally driving the first transmission gear unit to rotate. In this embodiment, the output gear 14 is a first spur gear, which includes a plurality of coggings, and each cogging includes a first side surface and a second side surface opposite to the first side surface.

In this embodiment, the first transmission gear unit is disposed between the input gear 13 and the output gear 14 and can be used for transmission. The first transmission gear unit includes a first tooth and a second tooth. The first tooth can be connected to the input gear. Meshing, the second tooth can mesh with the output gear, and it can keep in contact with the first side of the meshing slot, so that the second tooth can stably drive the output gear to rotate.

The second transmission gear unit is disposed between the input gear 13 and the output gear 14 and can be used for transmission. The second transmission gear unit includes a third tooth engaging a fourth tooth. The third tooth meshes with the input gear 13 and the fourth tooth. The fourth gear is engaged with the output gear 14 and the fourth tooth is kept in contact with the second side surface of the meshed groove, so that the fourth tooth can be stably driven by the output gear to rotate.

Specifically, the first transmission gear unit includes a first transmission gear combination 15a meshing with the input gear 13; of course, it can be understood that in other embodiments, it may also include a plurality of first transmission gear combinations. The first transmission gear combination 15 a is located between the input gear 13 and the output gear 14, and meshes with the input gear 13 and the output gear 14 respectively. The force applying component is connected to the first transmission gear combination 15a; it can provide a pre-tightening force for the input gear 13, the first transmission gear unit, the second transmission gear unit, and the output gear 14, so that the second tooth and the The first side of the meshing cogging remains in contact, and the fourth tooth is in contact with the fourth side of the meshing cogging, so that the input gear 13, the first transmission gear unit, the second transmission gear unit, The backlash of the output gear 14 is zero.

Further, the first transmission gear combination 15 a includes a first gear 151 and a second gear 152. The size of the first gear 151 is larger than the size of the input gear 13. Specifically, its diameter is larger than the diameter of the input gear 13 so as to achieve a first-level reduction. The first gear may be a second helical gear that meshes with the first helical gear. The size of the second gear 152 is smaller than the size of the first gear 151. Specifically, the diameter of the second gear 152 is smaller than the diameter of the first gear 151 and smaller than the diameter of the output gear 14. It is disposed at one end of the first gear 151 and The first gear 151 is fixedly connected and meshes with the output gear 14. The first gear 151 can be rotated by the first gear 151 to rotate, and then drive the output gear 14 to rotate, thereby achieving two-stage reduction. In this embodiment, the second gear 152 is a second spur gear that meshes with the output gear 14. In this embodiment, the teeth on the first gear 151 are first teeth, and the teeth on the second gear 152 are second teeth. The first force applying component is connected to the first gear 151. Of course, it can also be connected to the second gear 152, which can apply an axial force to the first transmission gear combination 15a. A helical gear and the second helical gear are converted into a rotational force, thereby driving the input gear 13, the first transmission gear unit, the second transmission gear unit, and the output gear 14 to rotate. The input gear 13, the first transmission gear unit, the first After the two transmission gear units and the output gear 14 rotate into place, the pressure between them forms a pre-tightening force, thereby keeping the second tooth in contact with the first side of the meshing groove and the fourth tooth meshing with it. The second side of the tooth groove is in contact.

In this embodiment, the second transmission gear unit includes a second transmission gear combination 16a meshing with the input gear 13; of course, it can be understood that in other embodiments, it may also include a plurality of second transmission gears. Gear combination 16a. The second transmission gear combination 16 a is located between the input gear 13 and the output gear 14, and meshes with the input gear 13 and the output gear 14 respectively. In other embodiments, the force applying component is connected to the second transmission gear combination 16a; it can provide a pre-tensioning force for the input gear 13, the first transmission gear unit, the second transmission gear unit, and the output gear 14, The second tooth is kept in contact with the first side of the toothed groove, and the fourth tooth is kept in contact with the fourth side of the toothed groove, so that the input gear 13 and the first transmission gear unit The backlash of the second transmission gear unit and the output gear 14 is zero.

Further, the second transmission gear combination 16 a includes a third gear 161 and further includes a fourth gear 162. The size of the third gear 161 is larger than the size of the input gear 13. Specifically, its diameter is larger than the diameter of the input gear 13 so as to achieve a first-level reduction. The first gear may be a third helical gear that meshes with the first helical gear. The size of the fourth gear 162 is smaller than the size of the third gear 161. Specifically, the diameter of the fourth gear 162 is smaller than the diameter of the third gear 161 and smaller than the diameter of the output gear 14. The third gear 161 is fixedly connected and meshes with the output gear 14. The third gear 161 can be rotated by the third gear 161 to rotate, and then the output gear 14 is rotated, thereby achieving two-stage reduction. In this embodiment, the fourth gear 162 is a second spur gear that meshes with the output gear 14. In this embodiment, the teeth on the third gear 161 are third teeth, and the teeth on the fourth gear 162 are fourth teeth. In other embodiments, the first force applying component is connected to the third gear 161. Of course, it can also be connected to the fourth gear 162, which can apply an axial force to the second transmission gear combination 16a. The axial force can be converted into a rotational force by the first helical gear and the third helical gear, thereby driving the input gear 13, the first transmission gear unit, the second transmission gear unit, and the output gear 14 to rotate. After a transmission gear unit, a second transmission gear unit, and an output gear 14 rotate in place, the pressure between them forms a pre-tensioning force, thereby keeping the second tooth in contact with the first side surface of the tooth groove engaged with it. The four teeth are in contact with the second side surface of the tooth groove with which they are engaged.

In this embodiment, the force applying component includes an elastic member 17 and a bearing 18 fixing the elastic member 17. The elastic member 17 is disposed on the first gear 151. Specifically, the elastic member 17 is sleeved on the second fixed shaft 112 and is located at an end remote from the second gear 152. The elastic member 17 can apply pressure to the first gear 151. The first transmission gear combination 15a is driven to move in the axial direction. The bearing 18 is sleeved on an end of the second fixed shaft 112 away from the first gear 151, and is rotated by the rotation of the first gear 151. The bearing 18 can be used to fix the elastic member 17 such that one end of the elastic member 17 and the first The gear 151 is in contact with the bearing 18 at the other end, and an axial force is generated. The helical teeth of the first gear 151 are converted into a rotational force, which drives the input gear 13 to rotate, so that the second tooth meshes with it. The first side of the tooth groove is in contact, and the fourth tooth is in contact with the second side of the tooth groove that is engaged with it, so that the input gear 13, the first transmission gear combination, the second transmission gear combination, and the output gear 14 The gap between them is zero. In addition, by driving the first transmission gear combination 15a to move in the axial direction, the teeth of the first gear 151 are moved up and down in the cogging on the input gear 13, thereby reducing the space between the gears. In this embodiment, preferably, the bearing 18 is a push bearing.

In other embodiments, the force applying component is not limited to an elastic member, which may be a worm, which can be rotated so that the first gear 151 can move up and down on the second fixed shaft 112, thereby driving the input gear 13 Turn.

FIG. 5 shows a second preferred embodiment of the reduction mechanism of the present invention, which is different from the first embodiment in that the first transmission gear unit further includes at least one other first transmission gear combination 15 to achieve multiple Variable speed transmission. In this embodiment, it also includes two first transmission gear combinations 15b, 15c. The two first transmission gear combinations 15 b and 15 c are disposed between the first transmission gear combination 15 a and the output gear 14 that mesh with the input gear 13. The second gear 152 of the first transmission gear combination 15a meshed with the input gear 13 is meshed with the first gear of the first transmission gear combination 15b disposed adjacent thereto. The first gear may be a spur gear. A first pinion gear disposed adjacent to the output gear 14 meshes with the output gear 14; a first gear located between the first gear 151 meshed with the input gear 13 and the second gear meshed with the output gear 14 The second gears adjacent to it are respectively meshed to form a multi-stage transmission. In this embodiment, the teeth on the first gear 151 of the first transmission gear combination 15a disposed adjacent to the input gear 13 are the first teeth, and the teeth of the first transmission gear combination 15c disposed adjacent to the output gear 14 are The teeth on the second gear are second teeth.

The second transmission gear unit further includes at least one other second transmission gear combination 16a, thereby realizing multi-speed transmission. In this embodiment, it also includes two second transmission gear combinations 16b, 16c. The two second transmission gear combinations 16 b and 16 c are disposed between the second transmission gear combination 16 a and the output gear 14 that mesh with the input gear 13. The fourth gear 162 of the second transmission gear combination 16a meshed with the input gear 13 is meshed with the third gear of the second transmission gear combination disposed adjacent thereto, and the third gear may be a spur gear. A third gear located between the third gear 161 meshed with the input gear 13 and the fourth gear meshed with the output gear 14 is meshed with a fourth gear disposed adjacently to form a multi-stage transmission. In this embodiment, the teeth on the third gear 161 of the second transmission gear combination 16a disposed adjacent to the input gear 13 are first teeth, and the teeth of the second transmission gear combination 16c disposed adjacent to the output gear 14 are The teeth on the fourth gear are the second teeth.

Figures 1 to 4 show a preferred embodiment of the driving device of the invention. The driving device can be used for decelerating driving, and its output speed is less than that of the motor. It has the advantages of strong transmission stability and high transmission accuracy.

As shown in FIGS. 1 to 4, the driving device includes a motor 12 and a reduction mechanism of the present invention. The motor 12 is disposed at one end of the casing 11 and an output shaft thereof extends from the casing 11. Specifically, it is disposed at One end of the base 111 and an output shaft thereof penetrate into the receiving space from the base 111. The input gear 13 is sleeved on the periphery of the output shaft and driven to rotate. The speed reduction mechanism has been described above, and is not repeated here.

It can be understood that the above examples only express the preferred embodiments of the present invention, and their descriptions are more specific and detailed, but cannot be understood as a limitation on the scope of the patent of the present invention; it should be noted that for those of ordinary skill in the art In other words, without departing from the concept of the present invention, the above technical features can be freely combined, and several modifications and improvements can be made, all of which belong to the protection scope of the present invention; All equivalent transformations and modifications made shall fall within the scope of the claims of the present invention.

Claims (10)

A reduction mechanism includes a housing (11), and an input gear (13), a first transmission gear unit, a second transmission gear unit, and an output gear (14) provided in the casing (11). ) And force components; The output gear (14) includes a plurality of coggings, and each cogging includes a first side surface and a second side surface opposite to the first side surface; The first transmission gear unit is disposed between the input gear (13) and the output gear (14); the first transmission gear unit includes a first tooth and a second tooth; and the first tooth and the The input gear (13) is meshed, and the second tooth is meshed with the output gear (14); The second transmission gear unit is disposed between the input gear (13) and the output gear (14). The second transmission gear unit includes a third tooth and a fourth tooth; The input gear (13) is meshed, and the fourth tooth is meshed with the output gear (14); The force application component provides a pre-tightening force for the input gear (13), the first transmission gear unit, the second transmission gear unit, and the output gear (14), so that the second tooth meshes with the cogging with it. The first side face of the first tooth is kept in contact, and the fourth tooth is kept in contact with the second side face of the tooth groove with which it is engaged. The reduction mechanism according to claim 1, wherein the first transmission gear unit includes a first transmission gear combination (15a) that meshes with the input gear (13); the first transmission gear combination (15a) The first transmission gear combination (15a) includes a first gear (151), the input gear (13) includes a first helical gear, and the first A gear (151) is a second helical gear that meshes with the first helical gear; the force applying component is connected to the first transmission gear combination (15a) and applies to the first transmission gear combination (15) Axial force, the first helical gear and the second helical gear convert the axial force into a rotational force, and drive an input gear (13), a first transmission gear unit, a second transmission gear unit, and an output gear ( 14) The pre-tensioning force is formed by the pressure between the gears after turning into position. The reduction mechanism according to claim 2, characterized in that the force applying component comprises a first gear (151) provided to apply pressure to drive the first transmission gear combination (15a) to move in the axial direction. An elastic member (17), and a bearing (18) fixing the elastic member (17); one end of the elastic member (17) is in contact with the first gear (151), and the other end is disposed in the bearing (18) ), In order to generate an axial force, the helical teeth of the first gear (151) convert the rotational force to drive the input gear (13) to rotate, so that the second tooth meshes with the tooth groove of the first tooth (151). The first side surface is in contact, and the fourth tooth is in contact with the second side surface of the tooth groove with which it is engaged. The reduction mechanism according to claim 3, wherein the first transmission gear combination (15a) further comprises a second gear (152); and the second gear (152) is disposed on the first gear (151). One end is fixedly connected with the first gear (151); The second transmission gear unit includes a second transmission gear combination (16a) that meshes with the input gear (13); the second transmission gear combination (16a) includes a third gear (161) and a fourth A gear (162), the fourth gear (162) is disposed at one end of the third gear (161) and is fixedly connected to the first gear (151); The third gear (161) includes a third helical gear that meshes with the first helical gear. The reduction mechanism according to claim 4, wherein the first gear (151) is meshed with the input gear (13), and the second gear (152) is meshed with the output gear (14); The teeth on the first gear (151) are the first teeth, the teeth on the second gear (152) are the second teeth, and the teeth on the third gear (161) are the The third tooth, and the tooth on the fourth gear (162) is the fourth tooth. The reduction mechanism according to claim 4, wherein the first transmission gear unit further comprises at least one other first transmission gear combination (15b or 15c); the at least one other first transmission gear combination ( 15b or 15c) is provided between the first transmission gear combination (15a) and the output gear (14) that mesh with the input gear (13); The teeth on the first gear (151) of the first transmission gear combination (15a) disposed adjacent to the input gear (13) are the first teeth; and are disposed adjacent to the output gear (14) The teeth on the second gear of the first transmission gear combination (15c) are the second teeth; The second transmission gear unit further includes at least one other second transmission gear combination (16b or 16c); the at least one other second transmission gear combination (16b or 16c) is provided in conjunction with the input gear (13) Between the meshed second transmission gear combination (16a) and the output gear (14); the third gear (161) of the second transmission gear combination (16a) disposed adjacent to the input gear (13) The upper teeth are the third teeth; the teeth on the fourth gear of the second transmission gear combination (16c) disposed adjacent to the output gear (14) are the fourth teeth. The reduction mechanism according to claim 4, characterized in that the output gear (14) includes a first spur gear, and the second gear (152) and the third gear (161) both include the output gear and the output gear. A second spur gear meshed by the gear (14); The diameter of the input gear (13) is smaller than the diameters of the first gear (151) and the third gear (161), and the diameters of the second gear (152) and the fourth gear (162) are smaller than The first gear (151) and the third gear (161); the diameter of the output gear (14) is larger than the diameters of the second gear (152) and the fourth gear (162). The reduction mechanism according to claim 4, characterized in that the casing (11) comprises a base (111) and an end cover (112) covering the base (111); the base (111) and all A receiving space is formed between the end covers (112); the motor (12) is disposed at one end of the base (111) and an output shaft thereof penetrates from the base (111) into the receiving space; the The other end of the elastic member (17) is in contact with the end cover (112). The reduction mechanism according to claim 8, characterized in that the axes of the first transmission gear combination (15a) and the second transmission gear combination (16a) are respectively arranged in parallel with the axis of the input gear (13); The axis of the input gear (13) is arranged parallel to the axis of the output gear (14); the first transmission gear combination (15a) and the second transmission gear combination (16a) are respectively disposed on the input gear ( 13) two opposite sides where the axis line and the axis line of the output gear (14) are connected; The base (111) is provided with a first fixed shaft (1111), a second fixed shaft (1112), and a third fixed shaft (1113) extending toward the accommodation space and arranged in parallel with each other; the output gear (14) ) Fixed on the first fixed shaft (1111); The output gear (14) is sleeved on the first fixed shaft (1111); The first transmission gear combination (15) is sleeved on the second fixed shaft (1112); The second transmission gear combination (16) is sleeved on the third fixed shaft; The end cover (112) is provided with a through hole for the first fixed shaft (1111) to pass through. A driving device, comprising a motor (12) and a reduction mechanism according to any one of claims 1 to 9, the motor (12) is disposed at one end of a casing (11) and an output shaft thereof is driven from the motor. The casing (11) is extended, and the input gear (13) is sleeved on the periphery of the output shaft. Zh