Multi-stage transmission mechanism for electric tool and electric tool

Abstract

The utility model discloses a multi-stage transmission mechanism for an electric tool and the electric tool. The multi-stage transmission mechanism comprises a shell; the motor is provided with a driving shaft, and a primary driving gear is arranged at the end part of the driving shaft; the first-stage speed reduction unit comprises a first-stage output shaft, a second-stage driving gear and a first-stage driven gear, and the first-stage driven gear is meshed with the first-stage driving gear; the second-stage speed reduction unit comprises a second-stage output shaft, a third-stage driving gear and a second-stage driven gear, and the second-stage driving gear is meshed with the second-stage driven gear; the third-stage speed reduction unit comprises a third-stage output shaft and a third-stage driven gear, the third-stage driving gear is meshed with the third-stage driven gear, and the third-stage output shaft can form a power output end of the electric tool; wherein the second-stage driving gear and the third-stage driving gear are completely the same in size and parameter; the first-stage output shaft and the second-stage output shaft are identical in size and parameter, and the second-stage driven gear and the third-stage driven gear are identical in size and parameter.

Description

Technical Field

[0001] This application relates to the field of power tool technology, and in particular to multi-stage transmission mechanisms for power tools and power tools. Background Technology

[0002] In the field of power tools, especially in tools such as cutting machines and wall cutters with saw blade diameters greater than 500mm, low-speed transmission mechanisms are required to deliver high torque output. Because these tools operate in environments with large amounts of water, dust, and mud, the rationality of the transmission mechanism design and the reliability of its sealing directly determine the average failure rate of the entire machine.

[0003] Existing multi-stage transmission mechanisms, such as the transmission mechanism for power tools and power tools with such a transmission mechanism proposed by the applicant CN222798094U, are compact in structure, which saves installation space, simplifies the structure of the transmission mechanism itself, and reduces costs. However, for some power tools, two-stage transmission mechanisms can no longer meet the usage requirements. Existing three-stage transmission mechanisms require more gears and drive shafts, and due to their arrangement, there are many types of gears and drive shafts, making management and installation difficult and maintenance costs high. Therefore, how to solve the above problems is the purpose of this application.

[0004] The above content is only used to help understand the technical solution of this application and does not represent an admission that the above content is the closest prior art to this application. Summary of the Invention

[0005] Based on this, this application provides a multi-stage transmission mechanism for power tools and a power tool to solve one of the aforementioned technical problems.

[0006] The technical solution adopted by this application to solve its technical problem is a multi-stage transmission mechanism for power tools and a power tool, comprising: a housing; a motor having a drive shaft, the end of which is provided with a primary drive gear; a primary reduction unit including a primary output shaft, a secondary drive gear, and a primary driven gear, the primary driven gear meshing with the primary drive gear; a secondary reduction unit including a secondary output shaft, a tertiary drive gear, and a secondary driven gear, the secondary drive gear meshing with the secondary driven gear; a tertiary reduction unit including a tertiary output shaft and a tertiary driven gear, the tertiary drive gear meshing with the tertiary driven gear, the tertiary output shaft constituting the power output end of the power tool; wherein the secondary drive gear and the tertiary drive gear have identical dimensions and parameters; the primary output shaft and the secondary output shaft have identical dimensions and parameters; the secondary driven gear and the tertiary driven gear have identical dimensions and parameters; the housing is provided with a first sealing structure and a second sealing structure on the drive shaft and the tertiary output shaft, respectively.

[0007] In some embodiments, the drive shaft is arranged perpendicular to the first-stage output shaft, and the first-stage driving gear and the first driven gear are bevel gears.

[0008] In some embodiments, the secondary drive gear is integrally formed with the primary output shaft to form a first gear shaft; the tertiary drive gear is integrally formed with the secondary output shaft to form a second gear shaft.

[0009] In some embodiments, keyways are provided on the primary output shaft, secondary output shaft, and tertiary output shaft for placing keys to transmit torque.

[0010] In some embodiments, limit circlips are provided on the first-stage output shaft, the second-stage output shaft, and the third-stage output shaft. The first-stage driven gear is located between the limit circlip and the second-stage driving gear and is restricted from axial movement. The second-stage driven gear is located between the limit circlip and the third-stage driving gear and is restricted from axial movement.

[0011] In some embodiments, a bearing is provided on the housing, and an abutment portion is formed on one side of the third-stage driven gear and the second-stage transmission gear. The abutment portion abuts against the inner ring of the bearing, and the third-stage driven gear is located between the retaining ring and the bearing and is restricted from axial movement.

[0012] In some embodiments, the abutment portion has an annular cross-sectional profile and forms a receiving cavity.

[0013] The first sealing structure includes: an O-ring, mounted on the drive shaft via a flange, which is also used to press against a bearing mounted on the drive shaft; and a first skeleton oil seal, disposed within the flange, for sealing the drive shaft.

[0014] In some embodiments, the second sealing structure includes: a labyrinth seal ring, which is a non-contact labyrinth seal ring, disposed on the third-stage output shaft; and a second skeleton oil seal, disposed on the third-stage output shaft, for sealing the third-stage output shaft.

[0015] An electric tool having the above-described multi-stage transmission mechanism for electric tools.

[0016] The beneficial effects of this application are as follows: the first-stage output shaft and the second-stage output shaft, the second-stage driving gear and the third-stage driving gear, and the second-stage driven gear and the third-stage driven gear in this application have the same size and parameters, which enables these components to be managed in batches and is convenient to install. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a three-dimensional structural diagram of this application.

[0019] Figure 2 This is a partial cross-sectional view of the three-dimensional structure of this application.

[0020] Figure 3 This is a schematic planar sectional view of this application.

[0021] Explanation of reference numerals in the attached diagram: 1. Housing; 11. First sealing structure; 111. O-ring seal; 112. Flange; 113. First skeleton oil seal; 12. Second sealing structure; 121. Labyrinth seal; 122. Second skeleton oil seal; 13. Bearing; 2. Motor; 21. Drive shaft; 211. First-stage drive gear; 3. First-stage reduction unit; 31. First-stage output shaft; 311. Keyway; 312. Limiting ring; 32. Second-stage drive gear; 33. First-stage driven gear; 4. Second-stage reduction unit; 41. Second-stage output shaft; 42. Third-stage drive gear; 43. Second-stage driven gear; 5. Third-stage reduction unit; 51. Third-stage output shaft; 52. Third-stage driven gear; 521. Abutment part; 5211. Receiving cavity. Detailed Implementation

[0022] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of the embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application. In addition, the technical solutions of various embodiments can be combined with each other, but this must be based on the ability of those of ordinary skill in the art to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such combination of technical solutions does not exist and is not within the scope of protection of this application.

[0023] In the embodiments of this application, please refer to Figure 1-3As shown, this application provides a multi-stage transmission mechanism for power tools, mainly comprising: a housing 1; a motor 2 having a drive shaft 21, the end of which is provided with a first-stage drive gear 211; a first-stage reduction unit 3 including a first-stage output shaft 31, a second-stage drive gear 32, and a first-stage driven gear 33, the first-stage driven gear 33 meshing with the first-stage drive gear 211; a second-stage reduction unit 4 including a second-stage output shaft 41, a third-stage drive gear 42, and a second-stage driven gear 43, the second-stage drive gear 32 meshing with the second-stage driven gear 43; and a third-stage reduction unit. 5. Includes a three-stage output shaft 51 and a three-stage driven gear 52. The three-stage driving gear 42 meshes with the three-stage driven gear 52. The three-stage output shaft 51 can form the power output end of the power tool. The two-stage driving gear 32 and the three-stage driving gear 42 have the same dimensions and parameters. The first-stage output shaft 31 and the second-stage output shaft 41 have the same dimensions and parameters. The second-stage driven gear 43 and the three-stage driven gear 52 have the same dimensions and parameters. The housing 1 is provided with a first sealing structure 11 and a second sealing structure 12 on the drive shaft 21 and the three-stage output shaft 51, respectively.

[0024] In the transmission structure, the connection relationship between the first-stage reduction unit 3 and the third-stage reduction unit 5 is hierarchical. While optimizing space, it also allows some parts to remain consistent and complete multi-stage reduction. Therefore, except for the first-stage driven gear 33 and the third-stage output shaft 51, the same parts can be used for the dimensional parameters, reducing manufacturing costs.

[0025] The following will continue to describe some preferred / improved embodiments based on the above embodiments. Any one of the following embodiments can be selected, or multiple embodiments can be combined.

[0026] Specifically, in order to optimize the arrangement of the reduction unit inside the housing 1, the drive shaft 21 is arranged perpendicularly to the first-stage output shaft 31, and the first-stage driving gear 211 and the first driven gear are bevel gears.

[0027] Preferably, since the parameters of the second-stage drive gear 32 and the first-stage output shaft 31, and the parameters of the third-stage drive gear 42 and the second-stage output shaft 41 are exactly the same, they can be integrated into one unit, which is convenient for manufacturing. The second-stage drive gear 32 and the first-stage output shaft 31 are integrally formed to form the first gear shaft; the third-stage drive gear 42 and the second-stage output shaft 41 are integrally formed to form the second gear shaft. Therefore, the parameters of the first gear shaft and the second gear shaft are exactly the same.

[0028] Specifically, keyways 311 are provided on the first-stage output shaft 31, the second-stage output shaft 41, and the third-stage output shaft 51 for placing keys to transmit torque.

[0029] Specifically, in order to limit the position of the driven gear, a limiting ring 312 is provided on the first-stage output shaft 31, the second-stage output shaft 41, and the third-stage output shaft 51. The first-stage driven gear 33 is located between the limiting ring 312 and the second-stage driving gear 32 and is restricted from axial movement. The second-stage driven gear 43 is located between the limiting ring 312 and the third-stage driving gear 42 and is restricted from axial movement.

[0030] Specifically, the housing 1 is provided with a bearing 13, which is located at both ends of the three output shafts. At the same time, the bearing 13 located on the output end side of the third-stage output shaft 51 can be used to restrict the third-stage driven gear 52. The third-stage driven gear 52 and the second-stage transmission gear have an abutment part 521 on one side. The abutment part 521 abuts against the inner ring of the bearing 13. The third-stage driven gear 52 is located between the limiting ring 312 and the bearing 13 and is restricted from axial movement.

[0031] Reference Figure 3 As shown, the cross-sectional profile of the abutment portion 521 is annular and forms a receiving cavity 5211. The receiving cavity 5211 can be used to accommodate the limiting retaining ring 312 or the side of the three-stage output shaft 51 connected to the bearing 13, preventing it from being restricted or stuck.

[0032] The first sealing structure 11 includes: an O-ring 111, which is mounted on the drive shaft 21 via a flange 112, which is also used to press the bearing 13 mounted on the drive shaft 21; and a first skeleton oil seal 113, which is disposed inside the flange 112 and is used to seal the drive shaft 21.

[0033] The second sealing structure 12 includes: a labyrinth seal 121, which is a non-contact labyrinth seal 121, and is disposed on the third-stage output shaft 51. During the sealing process, the rotating parts and the fixed parts do not come into direct contact, thus avoiding wear and heat caused by friction; and a second skeleton oil seal 122, which is disposed on the third-stage output shaft 51 and is used to seal the third-stage output shaft 51.

[0034] An electric tool having any of the above-described multi-stage transmission mechanisms for electric tools.

[0035] The various embodiments of this application have been described in detail above. To avoid obscuring the concept of this application, some details known in the art have not been described. Those skilled in the art can fully understand how to implement the technical solutions disclosed herein based on the above description. Finally, it should be noted that the above descriptions are merely preferred embodiments of this application, and the foregoing embodiments are only used to illustrate the technical solutions of this application, not to limit them; although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application.

Claims

1. A multi-stage transmission mechanism for power tools, characterized in that, include: case; An electric motor has a drive shaft, and a primary drive gear is provided at the end of the drive shaft; The first-stage reduction unit includes a first-stage output shaft, a second-stage driving gear, and a first-stage driven gear, wherein the first-stage driven gear meshes with the first-stage driving gear; The two-stage reduction unit includes a two-stage output shaft, a three-stage driving gear, and a two-stage driven gear, wherein the two-stage driving gear meshes with the two-stage driven gear; The three-stage reduction unit includes a three-stage output shaft and a three-stage driven gear. The three-stage driving gear meshes with the three-stage driven gear, and the three-stage output shaft can form the power output end of the power tool. The second-stage driving gear and the third-stage driving gear have the same dimensions and parameters; the first-stage output shaft and the second-stage output shaft have the same dimensions and parameters; and the second-stage driven gear and the third-stage driven gear have the same dimensions and parameters. The housing is provided with a first sealing structure and a second sealing structure on the drive shaft and the third-stage output shaft, respectively.

2. The multi-stage transmission mechanism for power tools according to claim 1, characterized in that, The drive shaft is arranged perpendicular to the first-stage output shaft, and the first-stage driving gear and the first driven gear are bevel gears.

3. The multi-stage transmission mechanism for power tools according to claim 1, characterized in that, The second-stage drive gear is integrally formed with the first-stage output shaft to form the first gear shaft; the third-stage drive gear is integrally formed with the second-stage output shaft to form the second gear shaft.

4. The multi-stage transmission mechanism for power tools according to claim 1, characterized in that, The primary, secondary, and tertiary output shafts are all equipped with keyways for placing keys to transmit torque.

5. The multi-stage transmission mechanism for power tools according to claim 1, characterized in that, Limiting rings are provided on the first-stage output shaft, the second-stage output shaft, and the third-stage output shaft. The first-stage driven gear is located between the limiting ring and the second-stage driving gear and is restricted from axial movement. The second-stage driven gear is located between the limiting ring and the third-stage driving gear and is restricted from axial movement.

6. The multi-stage transmission mechanism for power tools according to claim 5, characterized in that, The housing is provided with a bearing, and the third-stage driven gear and the second-stage transmission gear have an abutment portion on one side. The abutment portion abuts against the inner ring of the bearing, and the third-stage driven gear is located between the limiting ring and the bearing and is restricted from axial movement.

7. The multi-stage transmission mechanism for power tools according to claim 6, characterized in that, The cross-sectional profile of the abutment portion is annular and forms a receiving cavity.

8. The multi-stage transmission mechanism for power tools according to claim 1, characterized in that, The first sealing structure includes: an O-ring, which is mounted on the drive shaft via a flange, which is also used to press against the bearing mounted on the drive shaft; and a first skeleton oil seal, which is disposed inside the flange and is used to seal the drive shaft.

9. The multi-stage transmission mechanism for power tools according to claim 1, characterized in that, The second sealing structure includes: a labyrinth seal ring, which is a non-contact labyrinth seal ring, disposed on the third-stage output shaft; and a second skeleton oil seal, disposed on the third-stage output shaft, for sealing the third-stage output shaft.

10. A power tool, characterized in that, The power tool has a multi-stage transmission mechanism for power tools as described in any one of claims 1-9.

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