CN210697851U

CN210697851U - Dental handpiece speed-increasing bending machine

Info

Publication number: CN210697851U
Application number: CN201921251451.7U
Authority: CN
Inventors: 刘强
Original assignee: Tealth Foshan Medical Equipment Co ltd
Current assignee: Tealth Foshan Medical Equipment Co ltd
Priority date: 2019-08-05
Filing date: 2019-08-05
Publication date: 2020-06-09
Anticipated expiration: 2029-08-05

Abstract

The utility model discloses a dental handpiece acceleration rate bender, including the aircraft nose, first transmission shaft and secondary drive axle, the one end and the aircraft nose of first transmission shaft are connected, the other end is connected with the secondary drive axle transmission, first transmission shaft and secondary drive axle have the contained angle, install the needle in the aircraft nose, the periphery cover of needle is equipped with first gear, the one end that first transmission shaft and aircraft nose are connected is equipped with the second gear, second gear and first gear engagement, the contained angle has between first gear and the second gear, the second gear can eliminate the partial axial thrust that produces first gear at least. The utility model changes the gear matching structure, partially eliminates or even completely eliminates the axial acting force of the gear sleeved outside the needle, greatly reduces the friction between the bearings, and prolongs the service life of the bearings; meanwhile, the heat generation is greatly reduced, the use amount of cooling water in the operation process is further reduced, and a doctor can have a high-definition operation space.

Description

Dental handpiece speed-increasing bending machine

Technical Field

The utility model relates to the field of medical equipment, in particular to dental handpiece acceleration rate bender.

Background

The dental handpiece is divided into a high-speed dental handpiece and a low-speed dental handpiece, the rotating speed of the high-speed dental handpiece reaches 35-42 ten thousand revolutions per minute, and the dental handpiece is mainly used for treatment and repair such as punching, cutting and the like; while low speed dental handpieces are primarily used for drilling, milling and cutting treatments. The low-speed mobile phone is divided into a straight machine and a bending machine, wherein the straight machine is used for grinding and polishing and is mainly used for external treatment, and the bending machine is mainly used for internal treatment.

As shown in the chinese utility model with patent number 201620241116.9, it discloses an acceleration rate dental handpiece, including aircraft nose 1, first transmission shaft 2, secondary drive axle 3 and transition axle 4, the one end and the aircraft nose 1 of first transmission shaft 2 are connected, and the one end and the transmission of first transmission shaft 2 of transition axle 4 are connected, and the other end and the transmission of secondary drive axle 3 of transition axle 4 are connected, and first transmission shaft 2 and secondary drive axle 3 have the contained angle. This dental handpiece adopts two transmission shafts of transition shaft 4 connection, can effectively decompose the transmission action of two transmission shafts, and then reduces the loss to the transmission end, reduces the requirement to the material to increase acceleration rate dental handpiece life, reduce the cost to a great extent.

However, the above dental handpiece, like all bending machines on the market today, has the following disadvantages: as shown in fig. 1 to 4, in order to realize transmission connection with a certain angle (90 ° or more than 90 °), a gear (hereinafter referred to as a gear B) at one end of the first transmission shaft 2 connected to the handpiece 1 must be a bevel gear, and a gear (hereinafter referred to as a gear C) sleeved outside the needle and matched with the gear B must also be a bevel gear, and when the gear B rotates, two forces are generated to the gear C, one is a radial thrust for driving the gear C to rotate, and the other is an axial thrust for pushing the gear C to move toward a rear cover close to the handpiece 1. The bearing is a precision part of the turbine hand piece and is a vulnerable part, and if abrasion or other damage occurs, the hand piece is easily damaged. Because of the existence of the axial thrust, when the dental handpiece works, the needle can generate the force in the axial direction, and then the friction is generated between the bearings sleeved on the periphery of the needle, so that the service life of the bearings is seriously influenced.

SUMMERY OF THE UTILITY MODEL

The utility model aims at providing a dental handpiece acceleration rate bender that long service life, production of heat are less, can solve one of above-mentioned problem at least.

According to the utility model discloses an aspect provides a dental handpiece acceleration rate bender, including the aircraft nose, first transmission shaft and secondary drive axle, the one end and the aircraft nose of first transmission shaft are connected, the other end is connected with the secondary drive axle transmission, first transmission shaft and secondary drive axle have the contained angle, install the car needle in the aircraft nose, the periphery cover of car needle is equipped with bearing and first gear, the one end that first transmission shaft and aircraft nose are connected is equipped with the second gear, second gear and first gear engagement, the contained angle has between first gear and the second gear, the second gear can eliminate the partial axial thrust that produces first gear at least.

The conventional first gear and second gear are engaged by a standard bevel gear, and a radial and axial component force is generated on the conical surface, and the axial component force can cause a large amount of heat to be generated on the bearing. The utility model changes the traditional gear matching structure, partially eliminates or even completely eliminates the axial acting force of the gear sleeved outside the needle, greatly reduces the friction between the bearings and prolongs the service life of the bearings;

meanwhile, the friction between the bearings releases a large amount of heat, so that the temperature of the whole machine head is accelerated to rise, and the normal use is influenced. Because the bender is mainly used for intraoral treatment, during surgery, the bender head directly works in the mouth of a person, and the use requirement cannot be met if the temperature is too high. The existing method for solving the problem is to reduce the temperature by adopting a physical cooling mode of taking away the heat of the handpiece by an external cooling water pipe and the like, however, the used cooling water can be directly remained in the oral cavity of a person, if a mobile phone is used for a long time in the operation process, the cooling water is required to be continuously used for cooling, the water consumption is high, the operation surface becomes fuzzy, and the operation of a doctor is influenced; meanwhile, water in the oral cavity needs to be continuously pumped to meet the requirement of normal operation, which seriously influences the treatment experience of patients.

The utility model changes the gear matching structure, partially eliminates or even completely eliminates the axial acting force of the gear sleeved outside the needle, greatly reduces the friction between the bearings, and prolongs the service life of the bearings; meanwhile, the heat generation is greatly reduced, the use amount of cooling water in the operation process is further reduced, and a doctor can have a high-definition operation space.

In some embodiments, the first gear is a spur gear or a bevel gear. Therefore, when the first gear is a straight gear, the force applied to the first gear by the second gear is perpendicular to the outer wall of the first gear, namely the acting force is only transverse thrust and is completely used for driving the first gear to rotate, axial thrust cannot be generated, and the axial acting force of the gear sleeved outside the needle is completely eliminated. When the first gear is a bevel gear, the force applied to the first gear by the second gear is almost perpendicular to the outer wall of the first gear, so that a little axial thrust can be generated when the first gear is just in contact with the outer wall of the first gear, but the axial thrust can hardly be generated in the rotating process, and most of the axial acting force of the gear sleeved outside the needle is eliminated.

In some embodiments, one end of the second gear is provided with an opening matched with the first transmission shaft, the other end of the second gear is provided with a plurality of wedge-shaped teeth which are distributed in a circumferential array and are dispersed outwards, and the wedge-shaped teeth gradually taper from the root to the top. Therefore, when the first transmission shaft drives the second gear to rotate, the topmost end of the wedge-shaped teeth vertically acts on the tooth surface of the first gear, and because the first gear is a straight gear, the acting force of the wedge-shaped teeth acting on the first gear only generates radial thrust and cannot generate axial thrust.

In some embodiments, the wedge-shaped tooth is formed by three curved surfaces, namely a first curved surface, a second curved surface and a third curved surface, the first curved surface, the second curved surface and the third curved surface are connected with each other, the first curved surface is formed by three sections of lines, namely a first line, a second line and a third line, the second curved surface is formed by three sections of lines, namely a first line, a third line and a fourth line, the first curved surface and the second curved surface are intersected with the first line, the first curved surface and the second curved surface are symmetrical along a plane where the first line is located, and the first line, the second line, the third line, the fourth line and the fifth line are all arcs protruding outwards. The particular shape of the wedge-shaped teeth thus ensures that only radial forces are generated upon contact with the first gear wheel during rotation.

In some embodiments, one end of the second gear is provided with an opening matched with the first transmission shaft, the other end of the second gear is provided with a plurality of wedge-shaped teeth distributed in a circumferential array, and the wedge-shaped teeth gradually taper from the root to the top.

In some embodiments, the wedge-shaped tooth is formed by three curved surfaces, namely a first curved surface, a second curved surface and a third curved surface, the first curved surface, the second curved surface and the third curved surface are connected with each other, the first curved surface is formed by three sections of lines, namely a first line, a second line and a third line, the second curved surface is formed by three sections of lines, namely a first line, a fourth line and a fifth line, the first curved surface and the second curved surface intersect with the first line, the first curved surface and the second curved surface are symmetrically arranged along a plane where the first line is located, the first line, the second line and the fourth line are circular arcs which are convex outwards, and the third line and the fifth line are straight lines.

In some embodiments, the dental handpiece speed-increasing bending machine further comprises a transition shaft, one end of the transition shaft is in transmission connection with the first transmission shaft, the other end of the transition shaft is in transmission connection with the second transmission shaft, a third gear is arranged at the end of the first transmission shaft, the second transmission shaft is provided with a fourth gear, a fifth gear and a sixth gear are respectively arranged at the two ends of the transition shaft, the third gear is meshed with the fifth gear, and the fourth gear is meshed with the sixth gear. Therefore, the transition shaft is adopted to connect the two transmission shafts, so that the transmission actions of the two transmission shafts can be effectively decomposed, the loss of the transmission end is further reduced, and the requirement on materials is reduced; by adopting gear transmission, two groups of gears can respectively have larger contact areas, so that the moment acting on the teeth is reduced, the abrasion of the gears is further reduced, and the service life is prolonged.

In some embodiments, the third gear and the fifth gear are both bevel gears, the fourth gear is an internal gear, and the sixth gear is a spur gear. Therefore, the third gear is externally meshed with the fifth gear, the fourth gear is internally meshed with the sixth gear, and teeth can be tightly meshed with each other, so that pure rolling transmission is realized, the abrasion of the gears is effectively reduced, and the service life is prolonged.

In some embodiments, the dental handpiece speed-increasing bending machine further comprises a first shell, an elbow and a second shell which are connected in sequence, the first shell is connected with the handpiece, and the first transmission shaft, the second transmission shaft and the transition shaft are all positioned in a space formed by the first shell, the elbow and the second shell.

In some embodiments, a support block is provided within the head, and the transition shaft is supported by the support block. From this, the supporting shoe can guarantee the firm installation of transition axle in the dental handpiece.

The utility model has the advantages that:

the utility model changes the gear matching structure, partially eliminates or even completely eliminates the axial acting force of the gear sleeved outside the needle, greatly reduces the friction between the bearings, and prolongs the service life of the bearings; meanwhile, the heat generation is greatly reduced, the use amount of cooling water in the operation process is further reduced, and a high-definition operation space is provided for doctors.

Drawings

FIG. 1 is a schematic view of a prior art dental handpiece speed increasing bender;

FIG. 2 is a schematic cross-sectional view of the gear B and the gear C of the gear transmission shown in FIG. 1;

FIG. 3 is a schematic view of gear C of the gear transmission shown in FIG. 1;

FIG. 4 is a schematic view of gear B of the gear transmission shown in FIG. 1;

fig. 5 is a schematic perspective view of a dental handpiece speed-increasing bending machine according to embodiment 1;

FIG. 6 is a schematic cross-sectional view of the speed increasing bending machine of the dental handpiece shown in FIG. 5;

FIG. 7 is an enlarged schematic view of the dental handpiece speed increasing bender shown in FIG. 6 at A;

FIG. 8 is an enlarged view of the dental handpiece speed increasing bender shown in FIG. 6 at B;

FIG. 9 is a schematic perspective view of the first gear and the second gear of the dental handpiece speed increasing bender shown in FIG. 5;

FIG. 10 is a cross-sectional view of the first and second gears shown in FIG. 9;

FIG. 11 is a perspective view of a second gear of the speed increasing bender for dental handpiece shown in FIG. 5;

FIG. 12 is a schematic top view of the second gear of FIG. 11;

fig. 13 is a schematic perspective view of a dental handpiece speed-increasing bending machine according to embodiment 2;

FIG. 14 is a schematic cross-sectional view of the speed increasing bender of the dental handpiece shown in FIG. 13;

FIG. 15 is an enlarged view of the dental handpiece speed increasing bender shown in FIG. 13 at C;

FIG. 16 is a schematic perspective view of the first gear and the second gear of the dental handpiece speed increasing bender shown in FIG. 13;

FIG. 17 is a top view of the first gear and the second gear shown in FIG. 16;

FIG. 18 is a perspective view of the second gear shown in FIG. 16;

fig. 19 is a schematic top view of the second gear shown in fig. 18.

Reference numerals in FIGS. 5 to 19: 1-machine head; 2-a first transmission shaft; 3-a second transmission shaft; 4-a transition shaft; 5-needle turning; 6-a first gear; 7-a second gear; 8-a first housing; 9-bending the pipe; 10-a second housing; 11-a cooling water pipe; 12-a bearing; 21-a third gear; 31-a fourth gear; 41-fifth gear; 42-sixth gear; 71-opening a hole; 72-wedge teeth; 91-a support block; 721-first curved surface; 722-a second curved surface; 723-third curved surface; a-a first line; b-a second line; c-a third line; d-a fourth line; e-the fifth line.

Detailed Description

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

Example 1

Figures 5-12 schematically show a dental handpiece speed increasing bender according to an embodiment of the present invention.

As shown in fig. 5 to 12, the dental handpiece speed-increasing bending machine includes a handpiece 1, a first transmission shaft 2 and a second transmission shaft 3. One end of the first transmission shaft 2 is connected with the machine head 1, and the other end of the first transmission shaft is in transmission connection with the second transmission shaft 3. The first drive shaft 2 and the second drive shaft 3 are angled to form an elbow 9 of the dental handpiece. The machine head 1 is internally provided with a machine needle 5, and the peripheries of two ends of the part of the machine needle 5 positioned in the machine head 1 are sleeved with bearings 12. The bearing 12 is arranged to realize the rotatable installation of the needle 5. The periphery of the middle position of the part of the machine needle 5 located in the machine head 1 is fixedly sleeved with a first gear 6, and one end of the first transmission shaft 2 connected with the machine head 1 is fixedly sleeved with a second gear 7. The second gear 7 meshes with the first gear 6. The first gear 6 and the second gear 7 have an included angle therebetween, and the included angle between a line in which the radial direction of the first gear 6 is located and a line in which the radial direction of the second gear 7 is located in the present embodiment is substantially 120 °. The second gear 7 is able to eliminate at least part of the axial thrust generated on the first gear 6.

The first gear 6 may be a spur gear or a bevel gear.

As shown in the drawing, the first gear 6 of the present embodiment is a spur gear and the number of teeth of the first gear 6 is 19. Therefore, when the first gear 6 is a straight gear, the force applied to the first gear 6 by the second gear 7 is perpendicular to the outer wall of the first gear 6, i.e. the applied force is only a radial thrust, and is completely used for driving the first gear 6 to rotate, and no axial thrust is generated.

One end of the second gear 7 is provided with an opening 71 matched with the second transmission member, and the other end is provided with a plurality of wedge-shaped teeth 72 which are distributed in a circumferential array and are dispersed outwards. As shown in fig. 11, the outer wall of the wedge-shaped teeth 72 has a circumferential diameter that gradually increases from bottom to top. The wedge-shaped teeth 72 taper from root to tip. The number of the wedge teeth 72 of the second gear 7 of the present embodiment is 13. Therefore, when the second transmission member drives the second gear 7 to rotate, the topmost end of the wedge-shaped teeth 72 vertically acts on the tooth surface of the first gear 6, and because the first gear 6 is a straight gear, the acting force of the wedge-shaped teeth 72 acting on the first gear 6 only generates radial thrust and does not generate axial thrust.

As shown in fig. 7, each wedge-shaped tooth 72 is formed by three curved surfaces, namely a first curved surface 721, a second curved surface 722 and a third curved surface 723, enclosing the bottom surface. The first curved surface 721, the second curved surface 722 and the third curved surface 723 are connected to each other. The first curved surface 721 is formed by enclosing three lines, namely a first line a, a second line b and a third line c, which are connected in sequence. The second curved surface 722 is formed by enclosing three sections of lines, namely a first line a, a fourth line d and a fifth line e, which are connected in sequence. The third curved surface 723 is formed by the second line b and the fourth line d in a surrounding manner, and the third curved surface 723 and the outer wall of the second gear 7 are connected into a whole. The first curved surface 721 and the second curved surface 722 intersect at the first line a, and the first curved surface 721 and the second curved surface 722 are arranged symmetrically left and right along the plane of the first line a. The first, second, third, fourth and fifth lines a, b, c, d and e of the present embodiment are all arcs that are outwardly convex. As shown in fig. 5, when the first gear 6 is meshed with the second gear 7, the oblique side of the cross section of the topmost wedge tooth 72 of the second gear 7 is parallel to the horizontal line in the radial direction of the first gear 6. The particular shape of the wedge-shaped teeth 72 thus ensures that only radial forces are generated by contact with the first gear wheel 6 during rotation.

As shown in fig. 6 and 8, one end of the transition shaft 4 is in transmission connection with the first transmission shaft 2, the other end of the transition shaft 4 is in transmission connection with the second transmission shaft 3, and the first transmission shaft 2 and the second transmission shaft 3 form an included angle to form an elbow of the speed-increasing dental handpiece.

The end of the first transmission shaft 2 is provided with a third gear 21, the second transmission shaft 3 is provided with a fourth gear 31, the two ends of the transition shaft 4 are respectively provided with a fifth gear 41 and a sixth gear 42, the third gear 21 is meshed with the fifth gear 41, and the fourth gear 31 is meshed with the sixth gear 42.

The third gear 21 and the fifth gear 41 are both bevel gears, so that the first transmission shaft 2 and the transition shaft 4 form an angle therebetween, and the two gears can be tightly engaged during transmission. The fourth gear 31 is an internal gear, and the sixth gear 42 is a spur gear, so that the two gears can be tightly meshed during transmission. Two sets of gear pair transmission decompose the transmission action of first transmission shaft 2 and second transmission shaft 3 for the gear carries out pure roll transmission, reduces gear wear at to a great extent, makes the transmission process more steady.

The speed-increasing dental handpiece of the embodiment further comprises a first shell 5, an elbow 6 and a second shell 7 which are sequentially connected, wherein the first shell 5 is connected with the handpiece 1, and the first transmission shaft 2, the second transmission shaft 3 and the transition shaft 4 are all positioned in a space formed by the first shell 5, the elbow 6 and the second shell 7. A supporting block 61 is arranged in the elbow 6, and the transition shaft 4 is supported by the supporting block 61. The both ends cover of transition axle 4 is equipped with the bearing, and the bearing is supported by supporting shoe 61, realizes the rotatable installation of transition axle 4.

The peripheries of the first transmission shaft 2, the second transmission shaft 3 and the transition shaft 4 are all sleeved with corresponding bearings, so that smooth rotation of each part is guaranteed.

In addition, a cooling water pipe 11 is fixedly provided on the housing of the handpiece 1 in the present embodiment, and the cooling water pipe 11 is externally connected with cooling water for taking away heat generated by the handpiece 1.

The dental handpiece speed-increasing bending machine of the embodiment has the working process that:

the second transmission shaft 3 is driven by external power to rotate to drive the fourth gear 31 connected with the second transmission shaft to rotate, the fourth gear 31 drives the sixth gear 42 to rotate to drive the transition shaft 4 to rotate, the fifth gear 41 also rotates along with the transition shaft, the fifth gear 41 drives the third gear 21 sleeved at one end of the first transmission shaft 2 to rotate to drive the first transmission shaft 2 and the second gear 7 sleeved at the other end of the first transmission shaft 2 to rotate, the second gear 7 rotates to drive the first gear 6 fixedly sleeved at the periphery of the needle 5 to rotate to drive the needle 5 to rotate, so that internal transmission of the dental handpiece is completed, and an operation is completed through the rotating needle 5.

Due to the special design of the first gear 6 and the second gear 7, the second gear 7 can not generate axial thrust to the first gear 6 when rotating, namely the axial thrust generated by the first gear 6 is completely eliminated, so that the friction between bearings is greatly reduced, and the service life of the bearing 12 is prolonged.

Example 2

Fig. 13-19 schematically show a dental handpiece speed increasing bending machine according to another embodiment of the present invention.

As shown in fig. 13 to 19, the dental handpiece speed-increasing bender of the present embodiment has basically the same structure as the dental handpiece speed-increasing bender of example 1, and the differences are:

the first gear 6 and the second gear 7 of the present embodiment are different from those of embodiment 1 in structure, and the angle between the first gear 6 and the second gear 7 of the present embodiment is 90 °.

As shown in fig. 16 to 19, the first gear 6 of the present embodiment is a bevel gear and the number of teeth of the first gear 6 is 17. When the first gear 6 is a bevel gear, the force of the second gear 7 acting on the first gear 6 is almost perpendicular to the outer wall of the first gear 6, so that a little axial thrust is generated when the first gear is just in contact with the outer wall of the first gear 6, but the axial thrust is hardly generated in the rotating process, and most of the axial acting force of the gear sleeved outside the needle 5 is eliminated.

One end of the second gear 7 is provided with an opening 71 matched with the first transmission shaft 2, the other end of the second gear is provided with a plurality of wedge-shaped teeth 72 distributed in a circumferential array mode, and the circumference of the outer wall of each wedge-shaped tooth 72 is the same as the diameter of the second gear 7. The wedge-shaped teeth 72 taper from root to tip. The number of the wedge teeth 72 of the second gear 7 of the present embodiment is 16. Therefore, when the second transmission member drives the second gear 7 to rotate, the topmost end of the wedge-shaped teeth 72 vertically acts on the tooth surface of the first gear 6, and as the first gear 6 is a bevel gear, most of the acting force of the wedge-shaped teeth 72 which just starts to act on the first gear 6 is radial thrust, and only a small part of the acting force is axial thrust, therefore, the gear transmission structure can eliminate most of the axial thrust when in use, and compared with the traditional whole axial thrust, the gear transmission structure has obvious improvement.

As shown in fig. 18 and 19, each wedge-shaped tooth 72 is formed by three curved surfaces, namely a first curved surface 721, a second curved surface 722 and a third curved surface 723, enclosing the bottom surface. The first curved surface 721, the second curved surface 722 and the third curved surface 723 are connected to each other. The first curved surface 721 is formed by enclosing three lines, namely a first line a, a second line b and a third line c, which are connected in sequence. The second curved surface 722 is formed by enclosing three sections of lines, namely a first line a, a fourth line d and a fifth line e, which are connected in sequence. The third curved surface 723 is formed by the second line b and the fourth line d in a surrounding manner, and the third curved surface 723 and the outer wall of the second gear 7 are connected into a whole. The first curved surface 721 and the second curved surface 722 intersect at the first line a, and the first curved surface 721 and the second curved surface 722 are arranged symmetrically left and right along the plane of the first line a. In the present embodiment, the first line a, the second line b, and the fourth line d are all arcs protruding outward, and the third line c and the fifth line e are all straight lines.

Due to the special design of the first gear 6 and the second gear 7, the axial thrust generated on the first gear 6 when the second gear 7 rotates is mostly eliminated, so that the friction between the bearing and the needle 5 is greatly reduced, and the service life of the bearing 12 is further prolonged.

The utility model changes the gear matching structure, partially eliminates or even completely eliminates the axial acting force of the gear sleeved outside the needle 5, greatly reduces the friction between the bearings, and prolongs the service life of the bearing 12; meanwhile, the heat generation is greatly reduced, the consumption of cooling water in the operation process is reduced, the water consumption is low, the operation surface is clearly seen, and a high-definition operation space is indirectly provided for doctors.

What has been described above are only some embodiments of the invention. For those skilled in the art, without departing from the inventive concept, several modifications and improvements can be made, which are within the scope of the invention.

Claims

1. A dental handpiece speed-increasing bending machine comprises a handpiece (1), a first transmission shaft (2) and a second transmission shaft (3), one end of the first transmission shaft (2) is connected with the machine head (1), the other end of the first transmission shaft is in transmission connection with the second transmission shaft (3), an included angle is formed between the first transmission shaft (2) and the second transmission shaft (3), it is characterized in that a machine needle (5) is arranged in the machine head (1), a bearing (12) and a first gear (6) are sleeved on the periphery of the machine needle (5), a second gear (7) is arranged at one end of the first transmission shaft (2) connected with the machine head (1), the second gear (7) is meshed with the first gear (6), an included angle is formed between the first gear (6) and the second gear (7), the second gear (7) can eliminate at least part of the axial thrust generated on the first gear (6).

2. Dental handpiece speed-increasing bender according to claim 1, characterised in that said first gear (6) is a spur or bevel gear.

3. The dental handpiece speed-increasing bending machine according to claim 2, wherein one end of the second gear (7) is provided with an opening (71) matched with the first transmission shaft (2), the other end is provided with a plurality of wedge-shaped teeth (72) which are distributed in a circumferential array and are outwardly divergent, and the wedge-shaped teeth (72) are gradually tapered from the root to the top.

4. The dental handpiece speed-increasing bending machine according to claim 3, wherein the wedge-shaped teeth (72) are formed by enclosing three curved surfaces, namely a first curved surface (721), a second curved surface (722) and a third curved surface (723), the first curved surface (721), the second curved surface (722) and the third curved surface (723) are connected with each other, the first curved surface (721) is formed by enclosing three sections of lines, namely a first line (a), a second line (b) and a third line (c), the second curved surface (722) is formed by enclosing three sections of lines, namely a first line (a), a fourth line (d) and a fifth line (e), the first curved surface (721) and the second curved surface (722) are intersected with the first line (a), the first curved surface (721) and the second curved surface (722) are symmetrically arranged along the plane where the first line (a) is located, and the first line (a), the second line (b) and the third line (723) are located symmetrically, The third line (c), the fourth line (d) and the fifth line (e) are all arcs which are convex outwards.

5. The dental handpiece speed-increasing bending machine according to claim 1, wherein one end of the second gear (7) is provided with an opening (71) matched with the first transmission shaft (2), the other end is provided with a plurality of wedge-shaped teeth (72) distributed in a circumferential array, and the wedge-shaped teeth (72) gradually taper from the root to the top.

6. The dental handpiece speed-increasing bending machine according to claim 5, wherein the wedge-shaped teeth (72) are formed by enclosing three curved surfaces of a first curved surface (721), a second curved surface (722) and a third curved surface (723), the first curved surface (721), the second curved surface (722) and the third curved surface (723) are connected with each other, the first curved surface (721) is formed by enclosing three lines of a first line (a), a second line (b) and a third line (c), the second curved surface (722) is formed by enclosing three lines of a first line (a), a fourth line (d) and a fifth line (e), the first curved surface (721) and the second curved surface (722) are intersected with the first line (a), the first curved surface (721) and the second curved surface (722) are symmetrically arranged along the plane where the first line (a) is located, and the first line (a), the second line (b) and the fourth line (d) are convex arcs, the third line (c) and the fifth line (e) are straight lines.

7. The dental handpiece speed-increasing bending machine according to any one of claims 1 to 6, further comprising a transition shaft (4), wherein one end of the transition shaft (4) is in transmission connection with the first transmission shaft (2), the other end of the transition shaft (4) is in transmission connection with the second transmission shaft (3), a third gear (21) is arranged at the end of the first transmission shaft (2), a fourth gear (31) is arranged on the second transmission shaft (3), a fifth gear (41) and a sixth gear (42) are respectively arranged at the two ends of the transition shaft (4), the third gear (21) is meshed with the fifth gear (41), and the fourth gear (31) is meshed with the sixth gear (42).

8. Dental handpiece speed-increasing bender according to claim 7, characterized in that the third gear (21) and the fifth gear (41) are both bevel gears, the fourth gear (31) is an internal gear and the sixth gear (42) is a spur gear.

9. The dental handpiece speed-increasing bending machine according to claim 7, further comprising a first housing (8), an elbow (9) and a second housing (10) which are connected in sequence, wherein the first housing (8) is connected with the handpiece (1), and the first transmission shaft (2), the second transmission shaft (3) and the transition shaft (4) are all positioned in a space formed by the first housing (8), the elbow (9) and the second housing (10).

10. Dental handpiece speed-increasing bender according to claim 9, characterized in that a support block (91) is provided in the elbow (9), the transition shaft (4) being supported by the support block (91).