CN219911649U - Bidirectional rotation electric tool transmission mechanism and electric tool - Google Patents

Abstract

The utility model relates to the field of electric tools, in particular to a bidirectional rotary electric tool transmission mechanism and an electric tool, which are used for solving the technical problem that the electric tool with a rotary working part is difficult to control when working. The utility model provides a transmission mechanism, which comprises a shell, an inner shaft, an outer shaft and a second-stage planetary gear set accommodated in the shell, wherein the second-stage planetary gear set comprises a sun gear, a first-stage annular gear, a plurality of first-stage planetary gears, a second-stage annular gear and a plurality of second-stage planetary gears, the axle center of each first-stage planetary gear is fixed relative to the shell, the first-stage annular gear is rotatable relative to the shell, the second-stage annular gear is non-rotatable relative to the shell, the sun gear is meshed with each first-stage planetary gear and each second-stage planetary gear, each first-stage planetary gear is meshed with the first-stage annular gear in a rotating manner, and the first-stage annular gear drives the outer shaft to rotate along a second direction; each secondary planet gear is meshed with the secondary annular gear, and each secondary planet gear revolves along the sun gear to drive the inner shaft to rotate along the first direction.

Description

Bidirectional rotation electric tool transmission mechanism and electric tool

Technical Field

The utility model relates to the field of electric tools, in particular to an electric tool adopting a bidirectional rotary electric tool transmission mechanism.

Background

A power tool is a tool that can convert electric energy into mechanical energy, and generally uses an electric motor as a power source. Compared with the traditional manual tool, the electric tool has the advantages of high efficiency, accuracy, labor saving and the like, and can greatly improve the efficiency and quality of production work, thereby freeing the productivity. The electric tool can lighten the physical burden of people, accelerate the working process and improve the productivity.

Electric tools, such as a cleaning brush, a polisher, etc., for cleaning or polishing a surface of a workpiece or an object by rotating a working member are widely used in many industries, and work efficiency of people is improved.

The working member of the existing washing brush or polisher tends to rotate in one direction. Due to conservation of angular momentum, the working member of the brush or sander rotates in one direction, which results in a rotational force that rotates in the opposite direction on the brush or sander body. In addition, when the cleaning part of the cleaning brush or the polishing part of the polishing machine rotates to work, circumferential force is generated by friction with the working contact surface, and when the circumferential force of the cleaning part or the polishing part is balanced, lateral movement does not occur. However, in the actual use process, an operator often needs to move the cleaning brush or the polishing machine back and forth, and in the moving process, the cleaning part or the polishing part and the working contact surface may generate an inclination angle, so that the circumferential stress of the cleaning part or the polishing part is unbalanced, or the circumferential stress of the cleaning part or the polishing part is unbalanced due to the uneven working contact surface, so that the cleaning part or the polishing part and the working contact surface generate a lateral thrust, and a trend of lateral displacement of the cleaning brush or the polishing machine occurs. The superposition of the two forces can make the cleaning brush and the polisher difficult to control, and an operator needs to grasp the direction with force, so that the operator is easy to fatigue.

There is therefore a need in the art for a brush or sander that maintains a balance of circumferential forces on the working surface of the working member during operation and allows for easier control of the direction of operation by the operator using the tool.

Disclosure of Invention

The utility model aims to solve the technical problems that the prior art is overcome and a bi-directional rotation electric tool transmission mechanism and an electric tool are provided, so that the technical problems that the electric tool with a rotation working part is difficult to control during working are solved.

In order to achieve the technical aim, the bidirectional rotary electric tool transmission mechanism provided by the utility model comprises a shell, an inner shaft, an outer shaft and a secondary planetary gear set accommodated in the shell, wherein the secondary planetary gear set comprises a sun gear, a primary annular gear, a plurality of primary planetary gears, a secondary annular gear and a plurality of secondary planetary gears, the axle center of each primary planetary gear is fixed relative to the shell, the primary annular gear is rotatable relative to the shell, the sun gear rotates along a first direction and is meshed with each primary planetary gear, and each primary planetary gear rotates and is meshed with the primary annular gear to drive the outer shaft to rotate along a second direction;

the sun gear rotates along a first direction and is meshed with each secondary planet gear, each secondary planet gear is meshed with the secondary annular gear, the secondary annular gear is non-rotatable relative to the shell, and each secondary planet gear revolves along the sun gear to drive the inner shaft to rotate along the first direction;

the outer shaft and the inner shaft rotate in different directions to achieve bidirectional rotation.

Preferably, the rotation speed ratio of the outer shaft and the inner shaft is 1:1.5 to 1:5.

preferably, the secondary planetary gear set further includes a planet carrier and a plurality of planet shafts corresponding to the primary planetary gears, one end of each planet shaft is fixed on the housing, the other end is fixed on the planet carrier, and each primary planetary gear is sleeved on each planet shaft to realize autorotation.

Preferably, the secondary planetary gear set further includes a plurality of fixed shafts corresponding to the secondary planetary gears, each fixed shaft is fixed on the inner shaft, and each secondary planetary gear is sleeved on each fixed shaft to drive the inner shaft to rotate along the first direction.

Preferably, the inner rotary table and the outer rotary table are further included, the inner shaft is detachably and fixedly connected with the inner rotary table and coaxially rotates, and the outer shaft is detachably and fixedly connected with the outer rotary table and coaxially rotates.

Preferably, the outer rotary disc is provided with an avoidance groove for accommodating the inner rotary disc.

Preferably, the bottom surface of the inner rotating disc is arranged flush with the bottom surface of the outer rotating disc.

Preferably, a bearing or a shaft sleeve is arranged between the inner shaft and the outer shaft, and a bearing or a shaft sleeve is arranged between the outer shaft and the shell.

The utility model also provides an electric tool, which comprises a shell, a motor, a bidirectional rotating electric tool transmission mechanism and a driving mechanism, wherein the motor is arranged in the shell, the driving mechanism is driven by the motor, and working accessories are respectively arranged on the outer rotating disc and the inner rotating disc.

After the technical scheme is adopted, the utility model has the following beneficial effects.

1. The utility model provides a bidirectional rotary electric tool transmission mechanism, which comprises a secondary planetary gear set, wherein the axes of a plurality of primary planetary gears in the secondary planetary gear set are fixed relative to a shell, a primary annular gear is rotatable relative to the shell and a secondary annular gear is non-rotatable relative to the shell, so that the rotation of an inner shaft along a first direction and the rotation of an outer shaft along a second direction are realized, and the rotation of the outer shaft and the inner shaft along different directions is realized. First, the inner shaft and the outer shaft drive the inner rotary disc and the outer rotary disc to rotate along different directions, and the angular momentum generated by the rotation of the inner shaft and the outer shaft are opposite and can be offset to the greatest extent. And secondly, the inner rotary table and the outer rotary table rotate in different directions, when the cleaning part or the polishing part and the working contact surface generate an inclination angle or the working contact surface is uneven, opposite lateral forces generated by the respective rotation of the inner rotary table and the outer rotary table can be offset with each other as much as possible, so that the lateral thrust of the rotary table is reduced, the rotary table is not easy to generate displacement, and the control is easier. Third, by employing a planetary gear set transmission to achieve a larger reduction ratio, the motor may be a high speed motor, to achieve higher efficiency, smaller volume and lighter mass, faster corresponding times and start-up speeds, and cheaper prices. Fourth, through the reverse rotation of interior carousel and outer carousel, can carry out two-way washing or polish, be favorable to improving the effect of wasing or polishing, and the line after wasing or polishing is more even.

2. The rotation speed ratio of the outer shaft to the inner shaft is 1:5-1:1.5, and the outer shaft and the inner shaft have proper rotation speed ratios, so that opposite lateral forces and opposite angular momentum generated by the respective rotation of the inner rotating disc and the outer rotating disc can be counteracted as much as possible.

3. One end of the planetary shaft is fixed on the shell so that the primary planetary gear can rotate along the planetary shaft, and the primary planetary gear is meshed with the primary annular gear to drive the primary annular gear to rotate along the second direction, so that the outer shaft can rotate along the second direction; the other end of the planetary shaft is fixedly connected with the planet carrier, so that the relative shell of the secondary annular gear cannot rotate, and further the transmission output of the secondary planetary gear to the inner shaft is realized.

4. The inner shaft is detachably and fixedly connected with the inner rotary table, and the outer shaft is detachably and fixedly connected with the outer rotary table, so that the inner rotary table and the outer rotary table are more convenient to install, replace and maintain in the later period; the flexibility of the cleaning brush or the polisher is improved, and the proper inner rotating disc and the proper outer rotating disc can be replaced to meet the working requirement; in addition, the rotating shaft drives the turntable to connect in compact and stable mode, and this is favorable to raising the work efficiency of the inner and outer turntable.

5. The center part of outer carousel sets up the groove of dodging that is used for holding interior carousel, and interior carousel can install in the groove of dodging of outer carousel promptly, dodges the inner rotating disk through dodging the groove, can reduce the installation difference in height between inner carousel and the outer carousel to can reduce the difference in height between two clean annex that drive by inner rotating disk and outer carousel respectively, guarantee the effective scrubbing scope of cleaning brush, be favorable to improving the cleaning performance.

6. The bottom surface of interior carousel flushes the setting with the bottom surface of outer carousel to make the working face of the cleaning part or the portion of polishing that are driven respectively by interior carousel and outer carousel also can flush the setting, guarantee the operation effect of cleaning part or the portion of polishing when wasing or polishing, in addition, the counter side force that the rotation produced of balance carousel and outer carousel each that also can be better.

7. The outer rotary disc and the inner rotary disc rotate coaxially so as to better balance opposite lateral forces generated by the respective rotation of the outer rotary disc and the inner rotary disc.

8. By arranging the bearing or the shaft sleeve between the inner shaft and the outer shaft and between the outer shaft and the shell, the shaking between the inner shaft and the outer shaft and between the outer shaft and the shell during working is avoided, and the working stability of the equipment is improved.

9. The electric tool provided by the utility model adopts the bidirectional rotary electric tool transmission mechanism in any one of the technical schemes, so that the electric tool has all the technical effects of the bidirectional rotary electric tool transmission mechanism.

Drawings

Fig. 1 is a schematic cross-sectional view of a bi-directional rotary power tool transmission mechanism according to an embodiment of the utility model.

Reference numerals:

100. a secondary planetary gear set, 101, a sun gear, 102, a primary planetary gear, 103, a primary annular gear, 104, a planet carrier, 105, a planetary shaft, 111, a secondary planetary gear, 112, a secondary annular gear, 113 and a fixed shaft;

210. an outer shaft 220, an inner shaft 230, a lower housing portion;

300. the outer turntable, 301, avoiding the groove;

400. an inner turntable.

Detailed Description

The utility model provides a bidirectional rotary electric tool transmission mechanism, which comprises a shell, an inner shaft 220, an outer shaft 210 and a secondary planetary gear set 100 accommodated in the shell, wherein the secondary planetary gear set 100 comprises a sun gear 101, a primary annular gear 103, a plurality of primary planetary gears 102, a secondary annular gear 112 and a plurality of secondary planetary gears 111, the axle center of each primary planetary gear 102 is fixed relative to the shell, the primary annular gear 103 can rotate relative to the shell, the sun gear 101 rotates along a first direction and is meshed with each primary planetary gear 102, each primary planetary gear 102 rotates and is meshed with the primary annular gear 103, and the outer shaft 210 is driven by the primary annular gear 103 to rotate along a second direction; the sun gear 101 rotates along the first direction and engages each secondary planet gear 111, each secondary planet gear 111 engages the secondary ring gear 112, the secondary ring gear 112 is non-rotatable relative to the housing, and each secondary planet gear 111 revolves along the sun gear 101 to drive the inner shaft 220 to rotate along the first direction; the outer shaft 210 rotates in a different direction than the inner shaft 220 to achieve bi-directional rotation.

The technical solutions of the embodiments of the present utility model will be explained and illustrated below with reference to the drawings of the embodiments of the present utility model, but the following embodiments are only preferred embodiments of the present utility model, and not all embodiments. Based on the examples in the implementation manner, other examples obtained by a person skilled in the art without making creative efforts fall within the protection scope of the present utility model.

In the description of the present utility model, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "clockwise", "counterclockwise", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings are merely for convenience in describing the present utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be configured and operated in a specific orientation, and thus should not be construed as limiting the present utility model.

Furthermore, the terms "first," "second," and the like, are used for descriptive purposes only and are not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include one or more such feature. In the description of the present utility model, unless otherwise indicated, the meaning of "a plurality", "a number" or "a plurality" is two or more, unless otherwise clearly defined.

In the present utility model, unless explicitly specified and limited otherwise, the terms "mounted," "connected," "secured," and the like are to be construed broadly and may be, for example, fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium, and can be communication between two elements. The specific meaning of the above terms in the present utility model can be understood by those of ordinary skill in the art according to the specific circumstances.

The following description of the embodiments of the present utility model will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present utility model, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the utility model without making any inventive effort, are intended to be within the scope of the utility model.

As shown in fig. 1, the bi-directional rotary electric tool transmission mechanism according to the embodiment of the present utility model includes a housing, an inner shaft 220, an outer shaft 210, and a secondary planetary gear set 100 accommodated in the housing, wherein the secondary planetary gear set 100 includes a sun gear 101, a primary ring gear 103, and a plurality of primary planetary gears 102, and the primary ring gear 103 is rotatable relative to the housing.

The primary planet gears 102 are circumferentially distributed around the sun gear 101, the sun gear 101 rotates in a first direction, the axle center of each primary planet gear 102 is fixed relative to the housing so that each primary planet gear 102 meshes with the sun gear 101 to rotate, each primary planet gear 102 meshes with the primary annular gear 103 to drive the primary annular gear 103 to rotate in a speed-reducing manner in a second direction, and the primary annular gear 103 drives the outer shaft 210 to rotate in the second direction. The first direction can be forward rotation or reverse rotation, and the second direction is opposite to the first direction in rotation direction.

One end of the outer shaft 210 has a sidewall extending toward the secondary planetary gear set 100, a plurality of grooves are formed on the sidewall, and the outer wall of the primary ring gear 103 has protrusions extending toward the outer shaft 210, and the protrusions are cooperatively connected with the grooves so that the outer shaft 210 rotates with the rotation of the primary ring gear 103. The primary ring gear 103 may also be connected with the outer shaft 210 in other ways. For example: the primary ring gear 103 and the outer shaft 210 may be directly connected, or may be indirectly connected through other components; the connection mode can be pin holes, screw connection, clamping grooves, abutting and the like. The primary annular gear 103 is limited in the shell and cannot be separated, and the primary annular gear 103 is meshed with each primary planetary gear 102 circumferentially so that the primary annular gear 103 cannot deviate from the axis. Therefore, the primary ring gear 103 can be movably connected with the outer shaft 210 in a floating manner in the vertical direction, and the primary ring gear 103 needs to be always meshed with each primary planetary gear 102 in the floating process.

In order to fix the axle center of each primary planetary gear 102 relative to the housing, the secondary planetary gear set 100 further includes a plurality of planetary shafts 105, each planetary shaft 105 is disposed corresponding to each primary planetary gear 102, one end of each planetary shaft 105 is fixed on the planet carrier 104, each primary planetary gear 102 is sleeved on each planetary shaft 105, and each primary planetary gear 102 is fixed relative to the housing by the axle center of each primary planetary gear 102 through each planetary shaft 105 fixedly connected with the housing.

The sun gear 101 may be directly driven to rotate by a motor, or may be driven by a motor through a transmission mechanism. The motor preferably drives the sun gear 101 to rotate and achieve right angle drive through a set of planetary gear sets and a set of bevel gears. The planetary gear set transmission has a larger reduction ratio, and the motor can be selected to be a high-speed motor by adopting the planetary gear set transmission so as to obtain higher efficiency, smaller volume and lighter weight, quicker corresponding time and starting speed and lower price; and the planetary gear set has the characteristics of stable transmission, high transmission precision, compact structure, good reliability and the like. Through the right-angle transmission of a group of bevel gears, the motor can be horizontally arranged, so that the motor can be more stably operated, the vibration of the motor during operation is reduced, the height of a transmission mechanism can be reduced when the motor is horizontally arranged, the motor can be arranged in a handle of a cleaning brush or a polishing machine, the excessive size of the machine head of the cleaning brush or the polishing machine is avoided, the size can be further reduced, and the material is saved; meanwhile, compared with the traditional gear, the bevel gear has the advantages of higher transmission precision, good transmission efficiency, stable transmission, strong bearing capacity, low noise and the like.

The secondary planetary gear set 100 further includes a secondary ring gear 112, a plurality of secondary planet gears 111, and a plurality of fixed shafts 113 corresponding to the respective secondary planet gears 111, the secondary ring gear 112 being non-rotatable with respect to the housing. One end of the inner shaft 220 is disposed in the secondary planetary gear set 100, and a mounting hole corresponding to each fixed shaft 113 is formed thereon, one end of each fixed shaft 113 is fixed in the mounting hole, and each secondary planetary gear 111 is sleeved on each fixed shaft 113. The sun gear 101 rotates in the first direction, and each secondary planet gear 111 engages the sun gear 101 and the secondary ring gear 112 to cause each secondary planet gear 111 to revolve around the sun gear 101 in the first direction while decelerating in the first direction, and then each secondary planet gear 111 drives the inner shaft 220 to rotate together in the first direction.

In order to make the secondary ring gear 112 non-rotatable with respect to the housing, the secondary planetary gear set 100 further includes a planet carrier 104, where the planet carrier 104 is fixedly connected with the housing by screws, holes for installing the planet shafts 105 are formed in the planet carrier 104, one end of each planet shaft 105 is fixedly connected with the housing, and the other end is fixed to the planet carrier 104 and the planet carrier 104 is fixed with respect to the housing. The planet carrier 104 has a side wall extending towards the secondary annular gear 112, a groove is arranged on the side wall of the planet carrier 104, a protrusion is arranged on the outer side of the secondary annular gear 112, and the secondary annular gear 112 is fixed and non-rotatable relative to the shell through the matched connection of the protrusion and the groove.

It will be appreciated that in this embodiment, the secondary ring gear 112 is non-rotatable with respect to the housing through connection and cooperation with the planet carrier 104, and the secondary ring gear 112 may also be directly connected and cooperate with the housing to realize non-rotatable with respect to the housing. For example: a sidewall extending toward the secondary planetary gear set 100 may be provided between the inner shaft 220 and the outer shaft 210 at a lower portion of the housing, and the secondary ring gear 112 is coupled to the sidewall in such a way as to be non-rotatable with respect to the housing.

The electric tool transmission mechanism capable of rotating bidirectionally further comprises an inner rotary disc 400 and an outer rotary disc 300, wherein the inner shaft 220 is detachably and fixedly connected with the inner rotary disc 400 and coaxially rotates, the outer shaft 210 is detachably and fixedly connected with the outer rotary disc 300 and coaxially rotates, the inner shaft 220 drives the inner rotary disc 400 to rotate along a first direction, the outer shaft 210 drives the outer rotary disc 300 to rotate along a second direction, and the inner rotary disc 400 and the outer rotary disc 300 reversely rotate along different directions to realize bidirectional rotation of the inner rotary disc 400 and the outer rotary disc 300. The inner 400 and outer 300 rotatable disks may have cleaning or sanding attachments mounted thereon. When the inclination angle or the unevenness of the working contact surface is generated between the cleaning or polishing accessory and the working contact surface, the opposite lateral forces generated by the rotation of the inner rotating disc 400 and the outer rotating disc 300 can be counteracted as much as possible, so that the lateral thrust of the rotating disc is reduced, the rotating disc is not easy to displace, and the control is easier. And the inner rotating disc 400 and the outer rotating disc 300 rotate along different directions, and the angular momentum generated by the rotation of the inner rotating disc 400 and the outer rotating disc 300 are opposite and can be offset as much as possible.

However, since the diameter of the outer turntable 300 is larger than that of the inner turntable 400, if the rotational speed of the inner turntable 400 is close to that of the outer turntable 300, and the cleaning or polishing accessory and the working contact surface have an inclination angle or the working contact surface is uneven, the lateral force generated by the rotation of the outer turntable 300 is larger than that generated by the rotation of the inner turntable 400, and the angular momentum of the rotation of the outer turntable 300 is also larger than that of the rotation of the inner turntable 400, so that the outer turntable 300 and the inner turntable 400 have a tendency to generate lateral displacement even though rotating bidirectionally, and are difficult to control. Therefore, the rotation speed ratio of the outer rotor 300 and the inner rotor 400 needs to be adjusted so that the opposite lateral forces and angular momentum generated by the respective rotations of the outer rotor 300 and the inner rotor 400 are as close as possible, and thus can be offset as much as possible.

The rotation speed ratio of the outer rotary table 300 to the inner rotary table 400 is required to be determined according to the difference in outer diameter, shape, density, thickness, etc. of the outer rotary table 300 and the inner rotary table 400. Preferably, the ratio of rotation of outer rotor 300 to inner rotor 400 ranges from 1:1.5 to 1:5; more preferably, the speed ratio ranges from 1:1.8 to 1:4; most preferably, the speed ratio ranges from 1:2 to 1:3. The outer and inner rotary plates 300 and 400 are adjusted to a proper rotation speed ratio by a speed change structure so that opposite lateral forces and angular momentum generated by the respective rotation of the inner and outer rotary plates 400 and 300 can be offset as much as possible. The desired speed ratio is achieved by adjusting the number of teeth in each of the planetary gears and ring gears in each of the two-stage planetary gear set 100.

The inner shaft 220 and the outer shaft 210 are coupled to the inner and outer rotary discs 400 and 300 through the housing lower part 230, and bearings or bushings are provided between the inner shaft 220 and the outer shaft 210 in order to prevent shaking between the inner shaft 220 and the outer shaft 210; to avoid wobble between the inner shaft 220, the outer shaft 210 and the housing, bearings or bushings are provided between the outer shaft 210 and the housing lower portion 230. Further, a seal is secured to the housing to prevent liquids from entering the interior of the housing and affecting the proper operation of the transmission, and seals are provided between the inner shaft 220 and the outer shaft 210 and between the outer shaft 210 and the lower housing portion 230. The sealing element is preferably a framework oil seal. The sealing element is arranged below the bearing and the shaft sleeve.

As shown in fig. 1, in the bi-directional rotation electric tool transmission mechanism provided in the embodiment of the present utility model, unlike the foregoing embodiment, the outer rotating disc 300 is provided with the avoiding groove 301 for accommodating the inner rotating disc 400, that is, the inner rotating disc 400 may be installed in the avoiding groove 301 of the outer rotating disc 300, and the inner rotating disc 400 is avoided by the avoiding groove 301, so that the installation height difference between the inner rotating disc 400 and the outer rotating disc 300 may be reduced, and the situation that after the cleaning portion or the polishing portion is respectively installed on the outer rotating disc 300 and the inner rotating disc 400, the height difference between the inner cleaning portion and the outer cleaning portion or the polishing portion is avoided, so that a certain cleaning portion or polishing portion cannot work normally is avoided.

In this embodiment, preferably, the bottom surface of the inner rotating disc 400 is flush with the bottom surface of the outer rotating disc 300, so that the working surfaces of the cleaning part or the polishing part driven by the inner rotating disc 400 and the outer rotating disc 300 respectively can be flush, the working effect of the cleaning part or the polishing part during cleaning or polishing is ensured, and in addition, the opposite lateral forces generated by the respective rotation of the inner rotating disc 400 and the outer rotating disc 300 can be balanced better.

In other embodiments, a sliding structure is disposed between the avoidance groove 301 and the inner rotating disc 400, so that the inner rotating disc 400 can be better positioned in the avoidance groove 301 to avoid the inner rotating disc 400 from shaking relative to the outer rotating disc 300 during working, and meanwhile, the friction force of the inner rotating disc 400 is smaller when rotating relative to the outer rotating disc 300. The sliding structure may be a ball, a roller or a rolling bearing, etc. disposed on the inner turntable 400 and/or the avoiding groove 301, and when the transmission mechanism works, the surface of the inner turntable 400 and/or the inner wall of the avoiding groove 301 slides relative to the ball, the roller or the rolling bearing, and the ball, the roller or the rolling bearing rotates or rolls relative to the inner turntable 400 and/or the avoiding groove 301.

In one embodiment of the present utility model, an electric tool is provided, which includes a casing, a motor, and the motor is disposed in the casing, the electric tool adopts a bi-directional rotation electric tool transmission mechanism described in any of the foregoing embodiments, the motor drives the transmission mechanism, and working accessories are respectively mounted on the outer rotating disc 300 and the inner rotating disc 400.

Illustratively, the power tool is a sander, and sanding accessories are mounted on the outer and inner rotating discs 300, 400, respectively. The sanding accessory may be a sanding sheet, a polishing sheet, a sponge sheet, a wool felt, or the like.

Illustratively, the electric tool is a cleaning brush, and cleaning attachments are respectively mounted on the outer rotor 300 and the inner rotor 400 of the cleaning brush. The cleaning accessory can be a brush, a sponge brush, a scouring pad and the like.

It will be appreciated that the power tool is not limited to a sander and a cleaning brush, and that the power tool may be other power tool bodies having a bi-directional rotating working structure.

While the utility model has been described in terms of embodiments, it will be appreciated by those skilled in the art that the utility model is not limited thereto but rather includes the drawings and the description of the embodiments above. Any modifications which do not depart from the functional and structural principles of the present utility model are intended to be included within the scope of the appended claims.

Claims (10)

1. The electric tool transmission mechanism capable of rotating bidirectionally is characterized by comprising a shell, an inner shaft, an outer shaft and a second-stage planetary gear set accommodated in the shell, wherein the second-stage planetary gear set comprises a sun gear, a first-stage annular gear, a plurality of first-stage planetary gears, a second-stage annular gear and a plurality of second-stage planetary gears, the axle center of each first-stage planetary gear is fixed relative to the shell, the first-stage annular gear is rotatable relative to the shell, the sun gear rotates along a first direction and meshes with each first-stage planetary gear, and each first-stage planetary gear rotates and meshes with the first-stage annular gear so that the first-stage annular gear drives the outer shaft to rotate along a second direction;

the sun gear rotates along a first direction and is meshed with each secondary planet gear, each secondary planet gear is meshed with the secondary annular gear, the secondary annular gear is non-rotatable relative to the shell, and each secondary planet gear revolves along the sun gear to drive the inner shaft to rotate along the first direction;

the outer shaft and the inner shaft rotate in different directions to achieve bidirectional rotation.

2. The bi-directional rotating power tool transmission according to claim 1, wherein said outer shaft and said inner shaft rotate at a speed ratio of 1:1.5 to 1:5.

3. the bi-directional rotating power tool transmission mechanism of claim 1, wherein said secondary planetary gear set further comprises a planet carrier and a plurality of planetary shafts corresponding to each of said primary planetary gears, one end of each of said planetary shafts being fixed to said housing and the other end being fixed to said planet carrier, each of said primary planetary gears being sleeved on each of said planetary shafts to effect rotation.

4. The bi-directional rotating power tool transmission mechanism of claim 1, wherein said secondary planetary gear set further comprises a plurality of stationary shafts corresponding to each of said secondary planetary gears, each of said stationary shafts being secured to said inner shaft, each of said secondary planetary gears being disposed about each of said stationary shafts for driving rotation of said inner shaft in a first direction.

5. The bi-directional rotating power tool transmission mechanism of claim 1, further comprising an inner rotatable plate and an outer rotatable plate, wherein said inner shaft is removably fixedly connected to said inner rotatable plate and rotates coaxially, and wherein said outer shaft is removably fixedly connected to said outer rotatable plate and rotates coaxially.

6. The bi-directional rotating power tool transmission mechanism of claim 5, wherein said outer rotary plate has a relief groove therein for receiving said inner rotary plate.

7. The bi-directional rotating power tool transmission mechanism of claim 5, wherein the bottom surface of said inner rotatable plate is disposed flush with the bottom surface of said outer rotatable plate.

8. The bi-directional rotating power tool transmission mechanism according to claim 1, wherein a bearing or bushing is provided between the inner shaft and the outer shaft, and a bearing or bushing is provided between the outer shaft and the housing.

9. The electric tool comprises a casing and a motor, wherein the motor is arranged in the casing, and the electric tool is characterized by further comprising a bidirectional rotary electric tool transmission mechanism according to any one of claims 1 to 8, and the motor drives the bidirectional rotary electric tool transmission mechanism to drive the outer shaft and the inner shaft to rotate in different directions.

10. The electric tool, including casing, motor, the motor set up in the casing, its characterized in that still includes the electric tool drive mechanism of two-way rotation of any one of claims 5 to 7, the motor drive two-way rotation's electric tool drive mechanism is in order to drive outer axle with the interior axle rotates along different directions, the outer axle drives outer carousel rotates along the second direction, the interior axle drives the inner rotating disk rotates along first direction, install work annex respectively on outer carousel and the inner rotating disk.