Eccentric electric grinding tool and assembling method thereof

Abstract

The invention discloses an eccentric electric grinding tool and an assembling method thereof.The eccentric electric grinding tool comprises a motor, a transmission assembly and a waterproof assembly, and a motor output shaft is arranged at one end of the motor; the transmission assembly comprises a connecting shaft and a transmission gear ring, one end of the connecting shaft sleeves a motor output shaft, and the other end of the connecting shaft is connected with an eccentric polishing head; the transmission gear ring is located between the motor output shaft and the connecting shaft, the transmission gear ring is in interference fit with the motor output shaft, and the transmission gear ring is in clearance fit with the connecting shaft; the waterproof assembly comprises a waterproof cover and a sealing piece, and the waterproof cover covers the motor; the sealing piece is arranged on the transmission assembly and used for restraining liquid from being transmitted to the output shaft of the motor through the transmission assembly. The anti-seismic and waterproof performance of the electric grinding tool can be effectively enhanced.

Description

Technical Field

[0001] The invention relates to the technical field of grinding equipment, and in particular to an eccentric electric grinding tool and an assembling method thereof. Background Art

[0002] In the process of product preparation, the surface of the product is often processed by grinding. The grinding process is to mechanically grind the surface of the product by an eccentric grinding head with fixed sand grains such as a grinding wheel and sandpaper to remove burrs on the surface of the product, treat surface rust, and polish the surface. Various vibrations will inevitably occur during the grinding of the product by the eccentric grinding head. When this vibration is transmitted to the motor shaft, it is easy to cause collisions between the internal parts of the motor, thereby affecting the service life of the motor. In addition, in some special working conditions, underwater grinding is required, which undoubtedly increases the demand for the waterproof performance of the motor. Summary of the invention

[0003] In order to overcome the above-mentioned shortcomings, an object of the present invention is to provide an eccentric electric grinding tool and an assembly method thereof, which can effectively enhance the shock resistance and waterproof performance of the electric grinding tool.

[0004] In order to achieve the above purpose, one of the technical solutions adopted by the present invention is: an eccentric electric grinding tool, comprising A motor, one end of which is provided with a motor output shaft; The transmission assembly comprises a connecting shaft and a transmission gear ring, wherein one end of the connecting shaft is sleeved on the motor output shaft, and the other end is connected to an eccentric grinding head; the transmission gear ring is located between the motor output shaft and the connecting shaft, and the transmission gear ring and the motor output shaft have an interference fit, and the transmission gear ring and the connecting shaft have a clearance fit; The waterproof component comprises a waterproof cover and a sealing member, wherein the waterproof cover is arranged on the motor; the sealing member is arranged on the transmission component to prevent liquid from being transmitted to the output shaft of the motor through the transmission component.

[0005] The beneficial effects of the eccentric electric grinding tool of the present invention are: The motor output shaft is indirectly connected to the eccentric grinding head through the transmission assembly, which not only ensures that the rotational motion of the motor output shaft is transmitted to the eccentric grinding head, but also can use the transmission assembly to buffer the vibration of the eccentric grinding head during the grinding process, and avoid the vibration of the eccentric grinding head being directly transmitted to the motor output shaft; and the waterproof performance of the motor can be effectively improved by setting the waterproof assembly; In the transmission assembly, the transmission gear ring is interference-fitted with the motor output shaft to ensure the force synchronization between the transmission gear ring and the motor output shaft, so that the transmission gear ring and the motor output shaft rotate at the same frequency; and the transmission gear ring and the connecting shaft are clearance-fitted, which not only ensures the transmission of the rotational motion, but also utilizes the clearance between the transmission gear ring and the connecting shaft to release the vibration transmitted to the connecting shaft by the eccentric grinding head, so as to avoid the vibration being transmitted to the motor output shaft through the transmission gear ring, thereby improving the service life of the motor; In the waterproof component, the waterproof cover can provide waterproof protection for the surface of the motor, and the setting of the seal can effectively isolate the liquid leakage at the connection between the transmission component and the motor output shaft, preventing the liquid contacted by the eccentric grinding head from being transmitted to the motor output shaft through the transmission component, thereby improving the waterproof performance of the motor and the motor output shaft, and increasing the service life of the motor.

[0006] Further, the transmission gear ring includes a gear ring body, the surface of which is provided with a plurality of transmission teeth distributed in a circumferential array; a connection groove is provided at one end of the connection shaft facing the motor output shaft, and a plurality of transmission grooves corresponding to the transmission teeth are provided in the connection groove; the transmission teeth are located in the corresponding transmission grooves, and a gap is left between the transmission teeth and the transmission grooves. The stability of the transmission is ensured by the cooperation between the plurality of transmission teeth and the transmission grooves.

[0007] Furthermore, along the radial and circumferential directions of the transmission gear ring, gaps are reserved between the transmission teeth and the corresponding transmission grooves. Since the vibration of the eccentric grinding head is non-directional, when gaps are reserved in the radial and circumferential directions of the transmission gear ring, multi-directional buffering of the vibration can be achieved to achieve the purpose of quickly releasing the vibration.

[0008] Furthermore, the connecting groove includes a first annular groove and a second annular groove that are coaxial and interconnected, the radial dimension of the first annular groove is smaller than the radial dimension of the second annular groove, so that a step surface is formed at the junction of the first annular groove and the second annular groove; and the radial dimension of the first annular groove is adapted to the outer diameter of the gear ring body, and the radial dimension of the second annular groove is adapted to the radial dimension of the circumference formed by the groove bottoms of the plurality of transmission grooves. The setting of the first annular groove and the second annular groove enables the connecting groove to be adapted to the gear ring body and the transmission teeth, so as to improve the assembly stability of the connecting shaft and the transmission gear ring. The setting of the step surface can limit the axial displacement of the transmission teeth.

[0009] Furthermore, when the transmission tooth is located in the corresponding transmission groove, a gap is left between the transmission tooth and the step surface.

[0010] Furthermore, it also includes a protective sleeve mounted on the transmission assembly; one end of the protective sleeve extends toward the motor and is fixedly connected to the waterproof cover, and the other end extends toward the eccentric grinding head. The provision of the protective sleeve can stop and protect flying chips during the grinding process.

[0011] Furthermore, a first bearing is provided between the protective sleeve and the connecting shaft, one end of the first bearing abuts against the connecting shaft, and the other end is fixed by a first retaining spring, so as to ensure smooth rotation of the connecting shaft in the protective sleeve.

[0012] Specifically, the seal comprises a ring plate, a first sealing ring, and a second sealing ring; the ring plate is sleeved on the connecting shaft and is located between the eccentric grinding head and the first bearing, and one end of the ring plate abuts against the first bearing, and the other end is fixed by a second retaining ring; the inner ring surface of the ring plate abuts against the connecting shaft through the first sealing ring, and the outer ring surface of the ring plate abuts against the protective sleeve through the second sealing ring. The position of the ring plate can be limited by the cooperation of the first bearing and the second retaining ring, and the cooperation of the ring plate, the first sealing ring, and the second sealing ring can effectively prevent the water on the eccentric grinding head from moving toward the motor through the connecting shaft or the protective cover.

[0013] Furthermore, the sealing member further comprises a third sealing ring, and the third sealing ring is located between the waterproof cover and the protective sleeve, so as to prevent water from penetrating into the motor from the connection between the waterproof cover and the protective sleeve. The second technical solution adopted by the present invention is: an assembly method of an eccentric electric grinding tool, comprising the following steps: A waterproof cover is provided on the motor, and the motor output shaft is exposed outside the waterproof cover; and the transmission gear ring is interference fitted onto the motor output shaft; The first bearing is sleeved on the connecting shaft and fixed by a first retaining spring, so that two ends of the first bearing are respectively in contact with the connecting shaft and the first retaining spring; Press the first sealing ring and the second sealing ring onto the inner ring surface and the outer ring surface of the ring plate respectively, and fit the ring plate onto the connecting shaft until the ring plate abuts against the first bearing; then fix it with the second retaining spring so that the two ends of the ring plate abut against the first bearing and the second retaining spring respectively; Assemble the eccentric grinding head onto the connecting shaft by means of bolts, and then sleeve the protective sleeve onto the connecting shaft from the end close to the first bearing until the protective sleeve abuts against the ring plate; A third sealing ring is installed at a preset position of the waterproof cover, and then the end of the protective cover facing the motor is mounted on the waterproof cover, and the protective cover and the waterproof cover are fixed by bolts.

[0014] The eccentric electric grinding tool of the present invention is simple and convenient to assemble, has good assembly stability, and is easy to assemble in batches. In addition, since the transmission gear ring and the motor output shaft are pre-assembled into one body (referred to as the "first assembly"), and the connecting shaft, the eccentric grinding head and the protective sleeve are pre-assembled into one body (referred to as the "second assembly"), and then the first assembly and the second assembly are directly fixed by bolts, it is convenient to quickly disassemble them into the first assembly and the second assembly during subsequent maintenance, and then the connection between the transmission gear ring and the connecting shaft can be exposed without removing all parts, which is convenient for repairing and replacing the transmission components. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a schematic diagram of the three-dimensional structure of the electric grinding tool according to an embodiment of the present invention; Figure 2 is a schematic cross-sectional view of an electric grinding tool according to an embodiment of the present invention; Figure 3 It is a cross-sectional schematic diagram of the assembled motor and transmission assembly of the embodiment of the present invention; Figure 4 for Figure 3 A partial enlarged view of the middle A area; Figure 5 It is a schematic diagram of assembling the connecting shaft and the transmission gear ring according to an embodiment of the present invention; Figure 6 Schematic diagram of the structure of the ring plate according to an embodiment of the present invention.

[0016] In the figure: 1-motor; 11-motor output shaft; 21-connecting shaft; 211-transmission groove; 212-first ring groove; 213-second ring groove; 22-transmission gear ring; 221-transmission gear; 23-protective sleeve; 24-first bearing; 25-first retaining spring; 26-second retaining spring; 3-Eccentric grinding head; 41 - waterproof cover; 411 - power cord interface; 42 - ring plate; 421 - ring plate step surface; 43 - first sealing ring; 44 - second sealing ring; 45 - third sealing ring. DETAILED DESCRIPTION The preferred embodiments of the present invention are described in detail below in conjunction with the accompanying drawings so that the advantages and features of the present invention can be more easily understood by those skilled in the art, thereby making a clearer and more definite definition of the protection scope of the present invention.

[0017] Example See attached Figure 1-4As shown, an eccentric electric grinding tool of the present invention comprises a motor 1, a transmission assembly, and a waterproof assembly, wherein one end of the motor 1 is provided with a motor output shaft 11; the transmission assembly comprises a connecting shaft 21 and a transmission gear ring 22, one end of the connecting shaft 21 is sleeved on the motor output shaft 11, and the other end is connected to an eccentric grinding head 3. The transmission gear ring 22 is located between the motor output shaft 11 and the connecting shaft 21, and the transmission gear ring 22 and the motor output shaft 11 have an interference fit, and the transmission gear ring 22 and the connecting shaft 21 have a clearance fit. The waterproof assembly comprises a waterproof cover 41 and a seal, and the waterproof cover 41 is provided on the motor; the seal is provided on the transmission assembly to inhibit the liquid from being transmitted to the motor output shaft 11 through the transmission assembly.

[0018] When in use, the motor 1 is started, the motor output shaft 11 rotates and drives the transmission gear ring 22 to rotate synchronously, and the transmission gear ring 22 then transmits the rotational motion to the connecting shaft 21, thereby driving the eccentric grinding head 3 to rotate to perform the grinding action. During the grinding process, the vibration of the eccentric grinding head 3 will be directly transmitted to the connecting shaft 21. Due to the clearance fit between the connecting shaft 21 and the transmission gear ring 22, this vibration can be effectively mitigated, thereby avoiding the problem of shortening the life of the motor 1 caused by the vibration being directly transmitted to the motor output shaft 11.

[0019] In the prior art, the motor output shaft 11 is usually directly connected to the eccentric grinding head 3. When the eccentric grinding head 3 vibrates, the vibration will be directly transmitted to the motor output shaft 11. In the present application, the motor output shaft 11 is indirectly connected to the eccentric grinding head 3 through the setting of the transmission assembly, which not only ensures that the rotational motion of the motor output shaft 11 is transmitted to the eccentric grinding head 3, but also can utilize the transmission assembly to buffer the vibration of the eccentric grinding head 3 during the grinding process; and in the transmission assembly, due to the clearance fit between the transmission gear ring 22 and the connecting shaft 21, this vibration can be buffered again, thereby avoiding the vibration from being transmitted to the motor output shaft 11 via the transmission gear ring 22, thereby improving the service life of the motor 1.

[0020] When the eccentric grinding head 3 is operated underwater, the waterproof cover 41 can protect the surface of the motor 1, and the seal can isolate the liquid leakage at the connection between the transmission component and the motor output shaft 11, thereby preventing the liquid contacted by the eccentric grinding head 3 from being transmitted to the motor output shaft 11 through the transmission component, thereby improving the waterproof performance of the motor 1 and prolonging the service life of the motor 1.

[0021] In some embodiments, see Appendix Figure 4-5As shown, the transmission gear ring 22 includes a gear ring body, and a plurality of transmission teeth 221 distributed in a circumferential array are integrally arranged on the surface of one end of the gear ring body facing the motor 1; a connection groove sleeved on the gear ring body is provided at one end of the connecting shaft 21 facing the motor output shaft 11, and a plurality of transmission grooves 211 corresponding to the transmission teeth 221 are arranged in the connection groove. The transmission teeth 221 are located in the corresponding transmission grooves 211, and a gap is left between the transmission teeth 221 and the corresponding transmission grooves 211. The stability of the rotational motion transmission is ensured by the cooperation between the plurality of transmission teeth 221 and the transmission grooves 211.

[0022] Furthermore, along the radial direction and circumferential direction of the transmission gear ring 22, there is a gap between the transmission tooth 221 and the corresponding transmission groove 211. Since the vibration of the eccentric grinding head 3 is non-directional, when gaps are reserved in the radial direction and circumferential direction of the transmission gear ring 221, multi-directional buffering of the vibration can be achieved to achieve the purpose of quickly releasing the vibration. Specifically, along the radial direction of the transmission gear ring 22, there is a first gap between the transmission tooth 221 and the bottom of the corresponding transmission groove 211. Along the circumferential direction of the transmission gear ring 22, a second gap is respectively left between the two sides of the transmission tooth 221 and the two groove walls of the corresponding transmission groove 211. Furthermore, the first gap is 0.15~0.3mm, and the second gap is 0.1~0.15mm. Exemplarily, the first gap is 0.2mm and the second gap is 0.1mm.

[0023] In some embodiments, the size of the transmission teeth 211 along the circumferential direction of the transmission gear ring 22 gradually decreases from close to the gear ring body to away from the gear ring body.

[0024] In order to ensure synchronization of the transmission gear ring 22 with the rotation of the motor output shaft 11, in some embodiments, the cross-section of the motor output shaft 11 is an elliptical racetrack structure, and the inner ring surface shape of the gear ring body is adapted to the elliptical racetrack structure.

[0025] In some embodiments, see Appendix Figure 4 As shown, the connecting groove includes a first annular groove 212 and a second annular groove 213 which are coaxial and interconnected. The radial dimension of the first annular groove 212 is smaller than the radial dimension of the second annular groove 213, so that a step surface is formed at the junction of the first annular groove 212 and the second annular groove 213; and the radial dimension of the first annular groove 212 is adapted to the outer diameter of the gear ring body, and the radial dimension of the second annular groove 213 is adapted to the radial dimension of the circumference formed by the groove bottoms of the plurality of transmission grooves 211. The first annular groove 212 and the second annular groove 213 are provided so that the connecting groove can be adapted to the gear ring body and the transmission teeth 221, so as to improve the assembly stability of the connecting shaft 21 and the transmission gear ring 22. The step surface can limit the axial displacement of the transmission teeth 221. Furthermore, when the transmission teeth 221 are located in the corresponding transmission groove 211, a gap is left between the transmission teeth 221 and the step surface.

[0026] In some embodiments, see Appendix Figure 1-2 As shown, a protective sleeve 23 is also mounted on the connecting shaft 21, one end of the protective sleeve 23 extends toward the motor 1 and is fixed to the waterproof cover 41 by bolts, and the other end of the protective sleeve 23 extends toward the eccentric grinding head 3 to stop flying chips generated during the grinding process of the eccentric grinding head 3.

[0027] Since the protective sleeve 23 is fixedly connected to the waterproof cover 41, the protective sleeve 23 remains stationary during the process of the connecting shaft 21 rotating with the motor output shaft 11. In order to ensure the rotation stability of the connecting shaft 21, in some embodiments, a first bearing 24 is provided between the protective sleeve 23 and the connecting shaft 21, and the inner ring surface and the outer ring surface of the first bearing 24 abut against the connecting shaft 21 and the protective sleeve 23 respectively, and along the axial direction of the transmission gear ring 22, one end of the first bearing 24 abuts against the connecting shaft 21, and the other end is fixed by a first retaining spring 25.

[0028] In some embodiments, see Appendix Figure 3-4 As shown, the sealing member includes a ring plate 42, a first sealing ring 43, and a second sealing ring 44. The ring plate 42 is sleeved on the connecting shaft 21 and is located between the eccentric grinding head 3 and the first bearing 24, and one end of the ring plate 42 abuts against the first bearing 24, and the other end is fixed by the second retaining ring 26. The inner ring surface of the ring plate 42 is sealed against the connecting shaft 21 through the first sealing ring 43, and the outer ring surface of the ring plate 42 is sealed against the protective sleeve 23 through the second sealing ring 44. The position of the ring plate 42 can be limited by the cooperation of the first bearing 24 and the second retaining ring 26, and the cooperation of the ring plate 42, the first sealing ring 43, and the second sealing ring 44 can effectively inhibit the water on the eccentric grinding head 3 from moving toward the direction of the motor 1 through the connecting shaft 21 or the protective sleeve 23.

[0029] Furthermore, the inner and outer surfaces of the ring plate 42 are respectively provided with limiting grooves for accommodating the first sealing ring 43 and the second sealing ring 44. When the ring plate 42 is placed between the protective sleeve 23 and the connecting shaft 21, the first sealing ring 43 and the second sealing ring 44 can be sealed against the connecting shaft 21 and the protective sleeve 23 respectively.

[0030] In order to improve the assembly stability of the ring plate 42, in some embodiments, see the attached Figure 4 , 6As shown, the ring plate 42 includes a first ring plate body and a second ring plate body which are coaxially arranged. The first ring plate body and the second ring plate body have the same outer diameter, and the above-mentioned limiting groove is formed on the outer annular surface of the first ring plate body and the second ring plate body. The inner diameter of the first ring plate body is smaller than that of the second ring plate body, and the above-mentioned limiting groove is formed on the inner annular surface of the first ring plate body. The junction of the first ring plate body and the second ring plate body forms a ring plate step surface 421 for abutting the first bearing 24. Furthermore, the second ring plate body abuts on the protective sleeve 23. In this way, the second retaining ring 26, the connecting shaft 21, the first bearing 24 and the protective sleeve 23 can form a full coverage limit on the ring plate 42 in the axial, radial and circumferential directions to ensure the stability of the assembly position of the ring plate 42.

[0031] In some embodiments, the seal also includes a third sealing ring 45, which is located between the waterproof cover 41 and the protective cover 23 to prevent water from penetrating into the motor 1 from the connection between the waterproof cover 41 and the protective cover 23. Furthermore, a reserved groove for accommodating the third sealing ring 45 is provided on the outer wall of the waterproof cover 41.

[0032] In some embodiments, the waterproof cover 41 is a cylindrical structure with one end open, and a power line interface 411 communicating with the interior is provided on the waterproof cover 41. The motor 1 is built into the waterproof cover 41, and the motor output shaft 11 extends from the open end to facilitate connection with the transmission assembly.

[0033] In some embodiments, one end of the eccentric grinding head 3 is fixedly connected to the connecting shaft 21 by bolts, and the other end extends out of the protective sleeve 23. It should be noted that the eccentric grinding head 3 is a prior art, and its specific structure and working principle are not described in detail in this embodiment.

[0034] The present invention also provides an assembling method of an eccentric electric grinding tool, comprising the following steps: (1) A waterproof cover 41 is provided on the motor 1, and the motor output shaft 11 is exposed outside the waterproof cover 41; and the transmission gear ring 22 is interference fit onto the motor output shaft 11; (2) The first bearing 24 is mounted on the connecting shaft 21 and fixed by the first retaining spring 25 so that the two ends of the first bearing 24 abut against the connecting shaft 21 and the first retaining spring 25 respectively; (3) Press the first sealing ring 43 and the second sealing ring 44 onto the inner ring surface and the outer ring surface of the ring plate 42 respectively, and fit the ring plate 42 onto the connecting shaft 21 until the ring plate 42 abuts against the first bearing 24; then fix it with the second retaining ring 26 so that the two ends of the ring plate 42 abut against the first bearing 24 and the second retaining ring 26 respectively; (4) Assemble the eccentric grinding head 3 to the connecting shaft 21 by means of bolts, and then insert the protective sleeve 23 onto the connecting shaft 21 from the end close to the first bearing 24 until the protective sleeve 23 abuts against the ring plate 42; (5) Install the third sealing ring 45 at the preset position of the waterproof cover 41, then put the end of the protective cover 23 facing the motor 1 onto the waterproof cover 41, and fix the protective cover 23 and the waterproof cover 41 with bolts.

[0035] The above implementation modes are only for illustrating the technical concept and features of the present invention, and their purpose is to enable people familiar with this technology to understand the content of the present invention and implement it, and they cannot be used to limit the protection scope of the present invention. Any equivalent changes or modifications made according to the spirit of the present invention should be included in the protection scope of the present invention.

Claims

1. An eccentric electric grinding tool, characterized in that: include A motor, one end of which is provided with a motor output shaft; The transmission assembly comprises a connecting shaft and a transmission gear ring, wherein one end of the connecting shaft is sleeved on the motor output shaft, and the other end is connected to an eccentric grinding head; the transmission gear ring is located between the motor output shaft and the connecting shaft, and the transmission gear ring and the motor output shaft have an interference fit, and the transmission gear ring and the connecting shaft have a clearance fit; The waterproof component comprises a waterproof cover and a sealing member, wherein the waterproof cover is arranged on the motor; the sealing member is arranged on the transmission component to prevent liquid from being transmitted to the output shaft of the motor through the transmission component.

2. The eccentric electric grinding tool according to claim 1, characterized in that: The transmission gear ring includes a gear ring body, and a plurality of transmission teeth distributed in a circular array are arranged on the surface of the gear ring body; a connecting groove is opened at one end of the connecting shaft facing the motor output shaft, and a plurality of transmission grooves corresponding to the transmission teeth are arranged in the connecting groove; the transmission teeth are located in the corresponding transmission grooves, and a gap is left between the transmission grooves.

3. The eccentric electric grinding tool according to claim 2, characterized in that: Along the radial direction and the circumferential direction of the transmission gear ring, there are gaps between the transmission teeth and the corresponding transmission grooves.

4. The eccentric electric grinding tool according to claim 2, characterized in that: The connecting groove includes a first annular groove and a second annular groove which are coaxial and interconnected. The radial dimension of the first annular groove is smaller than the radial dimension of the second annular groove, so that a step surface is formed at the junction of the first annular groove and the second annular groove; and the radial dimension of the first annular groove is adapted to the outer diameter of the gear ring body, and the radial dimension of the second annular groove is adapted to the radial dimension of the circumference formed by the groove bottoms of the plurality of transmission grooves.

5. The eccentric electric grinding tool according to claim 4, characterized in that: When the transmission tooth is located in the corresponding transmission groove, a gap is left between the transmission tooth and the step surface.

6. The eccentric electric grinding tool according to claim 1, characterized in that: It also includes a protective sleeve sleeved on the transmission component; one end of the protective sleeve extends toward the motor and is fixedly connected to the waterproof cover, and the other end extends toward the eccentric grinding head.

7. The eccentric electric grinding tool according to claim 6, characterized in that: A first bearing is provided between the protective sleeve and the connecting shaft, one end of the first bearing abuts against the connecting shaft, and the other end is fixed by a first retaining spring.

8. The eccentric electric grinding tool according to claim 7, characterized in that: The sealing member comprises a ring plate, a first sealing ring and a second sealing ring; the ring plate is sleeved on the connecting shaft and is located between the eccentric grinding head and the first bearing, and one end of the ring plate abuts against the first bearing, and the other end is fixed by a second retaining ring; the inner ring surface of the ring plate abuts against the connecting shaft through the first sealing ring, and the outer ring surface of the ring plate abuts against the protective sleeve through the second sealing ring.

9. The eccentric electric grinding tool according to claim 8, characterized in that: The sealing member further comprises a third sealing ring, and the third sealing ring is located between the waterproof cover and the protective sleeve.

10. A method for assembling an eccentric electric grinding tool, characterized in that: The steps include: A waterproof cover is provided on the motor, and the motor output shaft is exposed outside the waterproof cover; and the transmission gear ring is interference fitted onto the motor output shaft; The first bearing is sleeved on the connecting shaft and fixed by a first retaining spring, so that two ends of the first bearing are respectively in contact with the connecting shaft and the first retaining spring; Press the first sealing ring and the second sealing ring onto the inner ring surface and the outer ring surface of the ring plate respectively, and fit the ring plate onto the connecting shaft until the ring plate abuts against the first bearing; then fix it with the second retaining spring so that the two ends of the ring plate abut against the first bearing and the second retaining spring respectively; Assemble the eccentric grinding head onto the connecting shaft by means of bolts, and then sleeve the protective sleeve onto the connecting shaft from the end close to the first bearing until the protective sleeve abuts against the ring plate; A third sealing ring is installed at a preset position of the waterproof cover, and then the end of the protective cover facing the motor is mounted on the waterproof cover, and the protective cover and the waterproof cover are fixed by bolts.

Images