Electric tool

Abstract

The utility model relates to an electric tool. The electric tool comprises a motor; the gearbox comprises a rear shell and a front shell which are sequentially arranged in the direction away from the motor, and a gear cavity is formed between the rear shell and the front shell; the multi-stage planetary gear train is arranged in the gear cavity and at least comprises a first-stage planetary gear train and a second-stage planetary gear train which are sequentially arranged in the direction away from the motor; the first-stage planetary gear train comprises a first inner gear ring which is connected to the front shell in a non-rotating mode. A groove is formed in the side, facing the rear shell, of the first inner gear ring and used for containing lubricating oil. According to the electric tool, the structure of the first inner gear ring of the first-stage planetary gear train is improved, the oil storage space is formed on the back face of the multi-stage planetary gear train, and the service life of the electric tool is prolonged.

Description

Technical Field

[0001] The utility model relates to the technical field of electric tools, in particular to an electric tool. Background Art

[0002] Electric tools usually use a multi-stage planetary gear train as a reduction mechanism to sequentially reduce the high-speed rotation generated by the motor to output a greater torque. In order to reduce the wear of the reduction mechanism, lubricating oil is usually applied during the assembly of the multi-stage planetary gear train, and the oil cavity formed by the front end of the multi-stage planetary gear train and the inner wall of the gear box is filled with lubricating oil. After the motor tool has been working for a period of time, the lubricating oil inside the multi-stage planetary gear train will gradually disappear, and the lubricating oil in the oil cavity at the front end of the multi-stage planetary gear train is difficult to transfer to the first-stage planetary gear train of the multi-stage planetary gear train, which will cause the first-stage planetary gear train to wear more, and eventually easily cause the electric tool to be damaged and unable to output torque. Utility Model Content

[0003] Based on the above-mentioned defects in the prior art, the purpose of the utility model is to provide an electric tool, improve the structure of the first inner gear ring of the first-stage planetary gear train, form an oil storage space on the back of the multi-stage planetary gear train, and extend the service life of the electric tool.

[0004] To this end, the utility model provides the following technical solutions.

[0005] The utility model provides an electric tool, comprising:

[0006] Motor;

[0007] The gear box comprises a rear shell and a front shell which are sequentially arranged in a direction away from the motor, and a gear chamber is formed between the rear shell and the front shell;

[0008] A multi-stage planetary gear train is arranged in the gear cavity, and at least includes a first-stage planetary gear train and a second-stage planetary gear train arranged in sequence along a direction away from the motor; the first-stage planetary gear train includes a first inner gear ring, which is non-rotatably connected to the front shell; the first inner gear ring is provided with a groove on the side facing the rear shell, and the groove is used to accommodate lubricating oil.

[0009] Preferably, a groove bottom wall of the groove is inclined toward the front shell in a radially inward direction.

[0010] Preferably, the angle between the groove bottom wall and the radial surface of the first inner gear ring (211) is less than or equal to 20°.

[0011] Preferably, a side wall of the first inner gear ring facing the rear shell is in the same plane as a bottom wall of the groove.

[0012] Preferably, the electric tool comprises a gasket disposed between the first inner gear ring and the rear housing, and an oil chamber for storing lubricating oil is formed between the groove and the gasket.

[0013] Preferably, a plurality of limiting grooves are provided on the inner wall of one end of the front shell, and the limiting grooves extend axially along the first inner gear ring; a plurality of first protrusions are provided on the outer wall of the first inner gear ring, and the first protrusions are engaged with the limiting grooves one by one.

[0014] Preferably, the gasket is provided with a plurality of second protrusions, the number of the second protrusions is less than or equal to the number of the limiting grooves, and one second protrusion is clamped in one of the limiting grooves.

[0015] Preferably, the first-stage planetary gear train also includes a first planetary gear set, a first sun gear and a first planet carrier, the first planetary gear set is respectively meshed with the first inner ring gear and the first sun gear, the first sun gear is coaxially connected to the motor, and the second sun gear of the second-stage planetary gear train is coaxially connected to the first planet carrier.

[0016] Preferably, the first sun gear is integrally formed on the output end of the motor, and the second sun gear is integrally formed on the first planet carrier.

[0017] Preferably, the multi-stage planetary gear train further includes a third-stage planetary gear train, and the power output end of the second-stage planetary gear train serves as the power input end of the third-stage planetary gear train.

[0018] The utility model has the following technical effects:

[0019] The utility model provides an electric tool, which improves the structure of the first inner gear ring of the first-stage planetary gear system. A groove is arranged on the back of the first inner gear ring to provide an oil storage space, so that lubricating oil can be continuously provided during the operation of the electric tool, thereby extending the service life of the electric tool. In addition, providing lubricating oil can also improve the tooth sound of the gear teeth of the multi-stage planetary gear system. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a partial structural schematic diagram of the gearbox assembly of the utility model;

[0021] Figure 2 This is a structural cross-sectional view of the first internal gear ring of the utility model;

[0022] Figure 3 It is a structural exploded diagram of the gearbox assembly of the utility model;

[0023] Figure 4 This is an exploded view of the gear box structure of the utility model;

[0024] Figure 5It is a schematic diagram of the three-dimensional structure of the first inner gear ring of the utility model.

[0025] Description of Reference Numerals

[0026] 100. Gear box assembly;

[0027] 1. gear box; 11. rear housing; 111. buckle; 12. front housing; 121. limit groove; 122. buckle groove;

[0028] 2. Multi-stage planetary gear train; 21. First-stage planetary gear train; 211. First inner gear ring; 2111. Groove; 21111. Groove bottom wall; 2112. First protrusion; 212. First planetary gear set; 213. First planet carrier; 22. Second-stage planetary gear train; 221. Second sun gear; 222. Second inner gear ring; 223. Second planetary gear set; 224. Second planet carrier; 23. Third-stage planetary gear train; 231. Third sun gear; 232. Third inner gear ring; 233. Third planetary gear set; 234. Third planet carrier; 2341. Waist-shaped through hole;

[0029] 3. Gasket; 31. Second protrusion. DETAILED DESCRIPTION

[0030] In order to make the technical solution and beneficial effects of the utility model more obvious and easy to understand, the following is a detailed description by listing specific embodiments. Unless otherwise defined, the technical and scientific terms used in this article have the same meaning as those in the technical field to which this application belongs.

[0031] In the description of the present invention, unless otherwise explicitly defined, terms such as “center”, “longitudinal”, “lateral”, “length”, “width”, “thickness”, “height”, “up”, “down”, “front”, “back”, “left”, “right”, “vertical”, “horizontal”, “top”, “bottom”, “inside”, “outside”, “clockwise”, “counterclockwise”, etc., indicating directions or positional relationships, are based on the directions or positional relationships shown in the accompanying drawings and are only for the convenience of simplified description of the present invention, and do not indicate that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and should not be understood as a limitation on the present invention.

[0032] In the present invention, the terms "first" and "second" are used only for the purpose of clear description and cannot be understood as the relative importance of the indicated features or the number of the indicated technical features. Therefore, the features defined as "first" and "second" can explicitly include at least one of the features. In the description of the present invention, "multiple" means at least two; "several" means at least one, unless otherwise clearly defined.

[0033] In the present invention, unless otherwise clearly defined, the terms "install", "connect", "connect", "fix", "set", etc. should be understood in a broad sense. For example, "connection" can be a fixed connection, a detachable connection, or an integral molding; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, or it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0034] In the present utility model, unless otherwise clearly defined, a first feature being “on”, “above”, “above”, “below”, “below”, “below” or “below” a second feature may mean that the first feature is in direct contact with the second feature, or the first feature and the second feature are in indirect contact through an intermediate medium. Moreover, a first feature being “on”, “above” or “above” a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the horizontal height of the first feature is higher than the horizontal height of the second feature. A first feature being “below”, “below” or “below” a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the horizontal height of the first feature is lower than the horizontal height of the second feature.

[0035] The "front" and "rear" mentioned in this utility model are all Figure 1 , Figure 3 and Figure 4 The markings in shall prevail.

[0036] According to the following Figures 1 to 5 The electric tool of the utility model is described in detail.

[0037] In this embodiment, if Figures 1 to 5 As shown, the electric tool includes a motor, a gear box 1 and a multi-stage planetary gear train 2. The multi-stage planetary gear train 2 is located at the front of the motor. The gear box 1 includes a rear shell 11 and a front shell 12 arranged in sequence in a direction away from the motor. A gear cavity is formed between the rear shell 11 and the front shell 12. The multi-stage planetary gear train 2 is arranged in the gear cavity. The gear box 1 and the multi-stage planetary gear train 2 constitute a gear box assembly 100. Figure 1 and Figure 3As shown, the multi-stage planetary gear train 2 includes a first-stage planetary gear train 21, a second-stage planetary gear train 22 and a third-stage planetary gear train 23 arranged in sequence in a direction away from the motor, and the power output by the motor is sequentially reduced and transmitted via the first-stage planetary gear train 21, the second-stage planetary gear train 22 and the third-stage planetary gear train 23. The first-stage planetary gear train 21 includes a first inner gear ring 211, a first planetary gear set 212, a first sun gear and a first planet carrier 213. The first inner gear ring 211 is non-rotatably connected to the front housing 12, the first planetary gear set 212 is mounted on the first planet carrier 213, the first planetary gear set 212 is meshed with the first inner gear ring 211 and the first sun gear (not shown in the figure), respectively, the first sun gear is coaxially connected to the motor, and the second sun gear 221 of the second-stage planetary gear train 22 is coaxially connected to the first planet carrier 213. A groove 2111 is provided on the side of the first inner gear ring 211 facing the rear housing 11, and the groove 2111 is used to accommodate lubricating oil.

[0038] By adopting the above technical solution, a groove 2111 is set on the back side of the first inner gear ring 211, and an oil storage space is formed on the back side of the first inner gear ring 211. Lubricating oil can be continuously provided during the operation of the power tool, thereby extending the service life of the power tool. In addition, providing lubricating oil can also improve the gear tooth sound of the multi-stage planetary gear system 2.

[0039] In one embodiment, if Figure 2 As shown, the bottom wall 21111 of the groove 2111 is inclined in the radial inward direction toward the front shell 12, so that the lubricating oil in the groove 2111 becomes liquid after being heated and flows more easily to the first planetary gear set 212 on the inclined guide of the bottom wall 21111 to achieve lubrication.

[0040] Furthermore, the angle between the groove bottom wall 21111 and the radial surface of the first inner gear ring 211 is less than or equal to 20°, so as to prevent the groove bottom wall 21111 from being too inclined and affecting the thickness of the first inner gear ring 211, thereby affecting the structural strength of the first inner gear ring 211. Preferably, the angle is 5°.

[0041] In one embodiment, if Figure 1 and Figure 2 As shown, the side wall of the first internal gear ring 211 facing the rear housing 11 is in the same plane as the bottom wall 21111 of the groove 2111, which is conducive to the flow of lubricating oil in the groove 2111 to the first planetary gear set 212 and is simple to process.

[0042] In one embodiment, if Figure 3 As shown, the electric tool includes a gasket 3 which is annular and is disposed between the first inner gear ring 211 and the rear housing 11 to prevent the first inner gear ring 211 from contacting and generating friction with the rear housing 11 . An oil chamber for storing lubricating oil is formed between the groove 2111 and the gasket 3 .

[0043] Furthermore, if Figure 3 As shown, the inner wall at one end of the front shell 12 is provided with four limiting grooves 121, which are arranged in a circumferential array, and the limiting grooves 121 extend along the axial direction of the first inner gear ring 211, and the limiting grooves 121 are open on both sides. The outer wall of the first inner gear ring 211 is provided with four first protrusions 2112. When assembling the first inner gear ring 211, the first inner gear ring 211 is inserted into the front shell 12 from the back to the front, and the first protrusions 2112 are engaged with the limiting grooves 121 one by one to limit the rotation of the first inner gear ring 211, and the groove wall on one side of the limiting groove 121 abuts against the front end surface of the first protrusion 2112, and the gasket 3 abuts against the rear end surface of the first inner gear ring 211 to limit the axial movement of the first inner gear ring 211.

[0044] Furthermore, if Figure 3 As shown, the gasket 3 is provided with two second protrusions 31 , the two second protrusions 31 are distributed along the radial direction of the gasket 3 , and one second protrusion 31 is engaged with one limiting groove 121 .

[0045] In one embodiment, if Figure 3 and Figure 4 As shown, the rear shell 11 has two buckles 111, which are distributed radially along the rear shell 11, and the inner wall of the front shell 12 is provided with two buckle grooves 122. The rear shell 11 and the front shell 12 are detachably connected through the buckles 111 and the buckle grooves 122.

[0046] In one embodiment, the first sun gear is integrally formed at the output end of the motor, and the second sun gear 221 is integrally formed at the first planet carrier 213 .

[0047] In one embodiment, if Figure 3As shown, the second-stage planetary gear train 22 also includes a second inner ring gear 222, a second planetary gear set 223 and a second planet carrier 224. The third-stage planetary gear train 23 includes a third sun gear 231, a third inner ring gear 232, a third planetary gear set 233 and a third planet carrier 234. The second inner ring gear 222 is mounted on the front housing 12 through a gear ring (not shown in the figure). The axial position of the second inner ring gear 222 can be adjusted by moving the lever on the gear ring back and forth, thereby adjusting the gear position. The second planetary gear set 223 is installed on the second planetary carrier 224, and the second planetary gear set 223 is respectively meshed with the second sun gear 221 and the second inner ring gear 222. The third inner ring gear 232 is embedded in the front housing 12. The third planetary gear set 233 is installed on the third planetary carrier 234, and the third planetary gear set 233 is respectively meshed with the third sun gear 231 and the third inner ring gear 232. The third planetary carrier 234 is provided with a waist-shaped through hole 2341, and the waist-shaped through hole 2341 is interference fit with the output shaft of the power tool (not shown in the figure). The output shaft is used to assemble the tool head. The power after deceleration of the multi-stage planetary gear train 2 is transmitted to the output shaft through the third planetary carrier 234.

[0048] It should be understood that the above embodiments are exemplary and are not intended to include all possible implementations included in the claims. Various modifications and changes may be made on the basis of the above embodiments without departing from the scope of the present disclosure. Similarly, the various technical features of the above embodiments may be arbitrarily combined to form other embodiments of the utility model that may not be explicitly described. Therefore, the above embodiments only express several implementations of the utility model and do not limit the scope of protection of the utility model patent.

Claims

1. An electric tool, characterized in that: The electric tool comprises: Motor; A gear box (1), comprising a rear shell (11) and a front shell (12) which are arranged in sequence in a direction away from the motor, wherein a gear chamber is formed between the rear shell (11) and the front shell (12); A multi-stage planetary gear train (2) is arranged in the gear cavity and comprises at least a first-stage planetary gear train (21) and a second-stage planetary gear train (22) which are arranged in sequence in a direction away from the motor; the first-stage planetary gear train (21) comprises a first inner gear ring (211) which is non-rotatably connected to the front housing (12); a groove (2111) is provided on a side of the first inner gear ring (211) facing the rear housing (11), and the groove (2111) is used to contain lubricating oil.

2. The electric tool according to claim 1, characterized in that: The groove bottom wall (21111) of the groove (2111) is inclined in a radially inward direction toward the front shell (12).

3. The electric tool according to claim 2, characterized in that: The included angle between the groove bottom wall (21111) and the radial surface of the first inner gear ring (211) is less than or equal to 20°.

4. The electric tool according to claim 1, characterized in that: A side wall of the first inner gear ring (211) whose gear teeth face the rear housing (11) is in the same plane as a groove bottom wall (21111) of the groove (2111).

5. The electric tool according to claim 1, characterized in that: The electric tool comprises a gasket (3) which is arranged between the first inner gear ring (211) and the rear housing (11); an oil chamber for storing lubricating oil is formed between the groove (2111) and the gasket (3).

6. The electric tool according to claim 5, characterized in that: A plurality of limiting grooves (121) are provided on the inner wall of one end of the front shell (12), and the limiting grooves (121) extend along the axial direction of the first inner gear ring (211); a plurality of first protrusions (2112) are provided on the outer wall of the first inner gear ring (211), and the first protrusions (2112) are engaged with the limiting grooves (121) one by one.

7. The electric tool according to claim 6, characterized in that: The gasket (3) is provided with a plurality of second protrusions (31), the number of the second protrusions (31) is less than or equal to the number of the limiting grooves (121), and one second protrusion (31) is snap-connected to one limiting groove (121).

8. The electric tool according to any one of claims 1 to 7, characterized in that: The first-stage planetary gear train (21) further comprises a first planetary gear set (212), a first sun gear and a first planet carrier (213); the first planetary gear set (212) is respectively meshed with the first inner gear ring (211) and the first sun gear; the first sun gear is coaxially connected to the motor; and the second sun gear (221) of the second-stage planetary gear train (22) is coaxially connected to the first planet carrier (213).

9. The electric tool according to claim 8, characterized in that: The first sun gear is integrally formed at the output end of the motor, and the second sun gear (221) is integrally formed at the first planet carrier (213).

10. The electric tool according to any one of claims 1 to 7, characterized in that: The multi-stage planetary gear train (2) further comprises a third-stage planetary gear train (23), and the power output end of the second-stage planetary gear train (22) serves as the power input end of the third-stage planetary gear train (23).

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