CN114871915A

CN114871915A - Sanding machine

Info

Publication number: CN114871915A
Application number: CN202210516970.1A
Authority: CN
Inventors: 钱雪江
Original assignee: Changzhou Jinmao Electric Tool Manufacture Co ltd
Current assignee: Changzhou Jinmao Electric Tool Manufacture Co ltd
Priority date: 2022-05-12
Filing date: 2022-05-12
Publication date: 2022-08-09
Anticipated expiration: 2042-05-12
Also published as: CN114871915B

Abstract

The invention provides a sanding machine, which comprises a shell, a motor, a sand bottom plate, a connecting shaft, cooling blades, a locking mechanism, a dust collection assembly, an inner gear ring and 1 sand bottom plate connecting screw, wherein the motor is fixedly arranged in the shell and provided with a motor shaft; the sand bottom plate comprises an eccentric block arranged inside and an outer gear ring matched with the inner gear ring; the outer gear ring is fixedly arranged on the periphery of the upper end of the eccentric block; when the sand bottom plate is installed, the outer gear ring is sleeved with the inner gear ring, the eccentric block of the sand bottom plate is inserted into the connecting shaft and is fixedly connected with the connecting shaft through 1 sand bottom plate connecting screw. The sanding machine has the advantages of small vibration and noise during working, convenient and quick installation and replacement of the sanding bottom plates with different shapes, high efficiency and good dust collection effect.

Description

Sanding machine

Technical Field

The invention relates to the technical field of electric tools, in particular to a sander with a conveniently replaceable sanding bottom plate.

Background

A sander is an electric tool used for sanding surfaces such as wooden products, metal products, plastic products, walls and the like. The handheld sander mainly comprises a sander body and two large parts of a sanding bottom plate connected with the sander body, sand paper is replaceably arranged on the sanding bottom plate, a motor in the sander body enables the sanding bottom plate to do reciprocating swing motion through an eccentric block (called as a balancing weight) fixedly arranged on a motor rotating shaft during working, and therefore sand paper on the sanding bottom plate is utilized to perform sanding operation on an operation object. In order to adapt to different operation objects and save equipment cost, a hand-held sander is provided with sand bottom plates with different shapes such as a circle, a square, a triangle and the like, and the sand bottom plates with different shapes are arranged on a sander body for different working conditions when the hand-held sander is used, for example, a sander disclosed in Chinese patent document with the publication number of CN209970387U is the existing common sander. The problems with such hand held sanders that are common today are: firstly, an eccentric block which drives a sand bottom plate to do rotary motion or reciprocating swing motion is fixedly arranged on a motor rotating shaft in a machine body, the eccentric block can only work optimally aiming at the sand bottom plate with a certain shape (such as a round shape), and when the sand bottom plate is replaced into a square, triangular or other shape, because the eccentric block is not designed aiming at the eccentric block, the handle on the sander mobile phone machine body is vibrated greatly and has large noise when being replaced and the hand feeling of an operator is poor, so that the working efficiency and the physical and mental health of the operator are influenced when the operator works for a long time; secondly, the sand bottom plate is generally fixedly connected with a connecting seat (also called a connecting flange, a bearing is arranged in the connecting seat and fixedly arranged on a motor rotating shaft) arranged in the machine body through 4 screws, and because 4 screw holes arranged on the connecting seat in the machine body are not easy to see, the four screws on the sand bottom plate and 4 screw holes on the connecting seat are difficult to align and position the upper screws when the sand bottom plate is replaced, and the efficiency of replacing the sand bottom plate is low; thirdly, only set up a two-sided fan blade that is driven by the motor shaft in the organism of this kind of hand-held grinder now, the upper end fan blade of two-sided fan blade carries out the forced air cooling to the motor, and the dust absorption function (the dust outlet of dust on following the organism of inhaling) of during operation is undertaken to the lower extreme fan blade, because structure and mounted position limit, the dust absorption effect is not good, influences operating personnel health and operating mass with rated load. Therefore, it is necessary to improve the existing sanding machine in view of the above technical problems.

Disclosure of Invention

The purpose of the invention is: in order to solve the technical problems in the prior art, the sander with the improved structure is provided.

The technical scheme of the invention is as follows: the sanding machine comprises a shell, a motor with a motor shaft and a sand bottom plate, wherein the motor is fixedly arranged in the shell, and the sand bottom plate is arranged below the shell and driven by the motor, and the sanding machine is structurally characterized in that: the sand bottom plate fixing device comprises a sand bottom plate, a motor shaft, a connecting shaft, a cooling fan blade, a locking mechanism, a dust collection assembly, an inner gear ring and 1 sand bottom plate connecting screw, wherein the sand bottom plate is fixedly arranged on the motor shaft; the sand bottom plate comprises an eccentric block arranged inside and an outer gear ring matched with the inner gear ring; the outer gear ring is fixedly arranged on the periphery of the upper end of the eccentric block; when the sand bottom plate is installed, the outer gear ring is sleeved with the inner gear ring, the eccentric block of the sand bottom plate is inserted into the connecting shaft and is fixedly connected with the connecting shaft through the sand bottom plate connecting screw.

The further scheme is as follows: the connecting shaft is a structural member formed by integrally or fixedly connecting a round rod-shaped shaft main body and a circular ring protruding part arranged on the periphery of the middle lower part of the shaft main body, the connecting shaft is fixedly connected with the motor shaft from the upper end of the shaft main body, a screw hole which is upwards recessed from the lower end face is arranged in the shaft main body, and the connecting shaft is rotatably arranged in the shell by a connecting shaft supporting bearing arranged on the connecting shaft; the sand bottom plate connecting screw is matched with a screw hole of the shaft main body of the connecting shaft; the inner gear ring is fixedly connected with the lower end face of the circular ring protruding part of the connecting shaft.

The further scheme is as follows: the locking mechanism comprises a locking ring, a locking pin button and a return spring; the locking ring is a structural member which is circular as a whole, a group of radial inwards concave slotted holes are arranged at intervals on the periphery of the locking ring and are used as pin holes, and the locking ring is fixedly arranged on the connecting shaft and is positioned below the cooling fan blades; the lock pin is a rod-shaped structural member matched with the pin hole of the lock ring, the lock pin button is a plate body member, the outer end of the lock pin is integrally or fixedly connected with the lock pin button, and the reset spring is used for driving the inner end of the lock pin to automatically recover to a separation state from an insertion locking state with the pin hole of the lock ring after the lock pin button is loosened; the lock pin and the reset spring are movably arranged in the shell, and the lock pin button is movably arranged on the shell.

The further scheme is as follows: the dust collection component comprises a dust collection fan blade, a wind collection cover and a dust outlet nozzle; the dust collection fan blade is fixedly arranged on the lower side of the connecting shaft and is close to the sand bottom plate; the wind collecting cover is a cylindrical structural member, is fixedly arranged in the shell and is provided with a dust outlet; one port of the air collecting cover is arranged close to the dust collection fan blade, and the other port of the air collecting cover is communicated with the dust outlet nozzle.

The further scheme is as follows: the sand bottom plate also comprises a bottom plate, a bracket fixedly arranged at the upper end of the bottom plate, and an eccentric block supporting bearing fixedly arranged in the bracket, wherein the eccentric block is rotatably sleeved with an inner ring of the eccentric block supporting bearing, the eccentric block is provided with a shaft connecting hole which is vertically communicated, the middle part of the bottom plate is provided with a screw hole which is vertically communicated and is matched with the shaft connecting hole of the eccentric block, and the integral structure and the shape of the eccentric block are matched with the shape of the bottom plate; the eccentric block is inserted into the connecting shaft through a shaft connecting hole and fixedly connected with the connecting shaft through the sand bottom plate connecting screw passing through the screw hole of the bottom plate.

The further scheme is as follows: the bottom plate of the sand bottom plate is a circular plate body, and correspondingly, the sand bottom plate is a circular sand bottom plate.

The further scheme is as follows: the bottom plate of the sand bottom plate is a triangular plate or a square plate, and correspondingly, the sand bottom plate is a triangular sand bottom plate or a square sand bottom plate; the shell also comprises 4 swing brackets which are integrated with the shell or fixedly connected with the shell and arranged in the shell; the triangular sand bottom plate and the square sand bottom plate respectively comprise 4 positioning columns which are fixedly or integrally arranged on the support, and the 4 positioning columns are correspondingly inserted with 4 swing supports of the shell during installation.

The invention has the positive effects that: (1) according to the sander, through the improved design of the whole structure, particularly, the eccentric block is arranged in the sanding bottom plate, so that the eccentric block can adopt the structural design with optimal adaptability for sanding bottom plates with different shapes, vibration and noise of the sander can be greatly reduced when the sander is used, and the technical problems that in the prior art, only 1 eccentric block fixedly arranged on a motor rotating shaft in the sander body cannot be optimally adapted to round, triangular and square sanding bottom plates simultaneously, so that the sander is large in vibration and noise when in work, an operator feels poor, and working efficiency and physical and psychological health of the operator are influenced when the sander works for a long time can be effectively solved. (2) According to the sander, the connecting shaft is fixedly arranged on the rotating shaft of the motor, the screw holes are formed in the lower end of the connecting shaft, the inner gear ring for assisting positioning is fixedly arranged on the connecting shaft, the outer gear ring matched with the inner gear ring is arranged on the sand bottom plate, the connecting shaft is inserted into the eccentric block arranged on the sand bottom plate, the locking mechanism for locking the connecting shaft to prevent the connecting shaft from rotating during installation or replacement of the sand bottom plate is arranged on the sand bottom plate, and the like, so that the sander is convenient and quick to operate during installation and replacement, time-saving and labor-saving, high in efficiency of installing and replacing the sand bottom plate, and capable of effectively solving the technical problems that in the prior art, the aligning and positioning of screws on the 4 screw holes of the sand bottom plate fixedly connected with the connecting seat arranged in the sander body through the 4 screws is difficult, and the efficiency of replacing the sand bottom plate is low. (3) The sanding machine is characterized in that the cooling fan blade is arranged on the motor shaft close to the motor, the dust collection fan blade is arranged on the lower side of the connecting shaft close to the sand bottom plate, and compared with the prior art that only one double-sided fan blade driven by the motor rotating shaft is arranged in the machine body (the fan blade at the upper end is used for air cooling of the motor, and the fan blade at the lower end is used for dust collection during working), the double-sided fan blade is used for carrying out double functions of air cooling and dust collection of the motor, so that the cooling fan blade can not be arranged close to the motor and can not be arranged close to the sand bottom plate; the dust absorption fan blade is close to the sand bottom plate setting, can make its dust collection efficiency can reach prior art more than 3 times, and dust absorption effect is better, is of value to operating personnel's healthy and improvement construction quality.

Drawings

FIG. 1 is a schematic external view of the present invention;

FIG. 2 is a schematic view of the front cover of the housing of FIG. 1 with portions broken away;

FIG. 3 is a schematic perspective view of the housing of FIG. 1 with the front cover removed, showing the locking mechanism in an unlocked state, i.e., a state of the locking mechanism during normal use;

FIG. 4 is an enlarged schematic view of the structure at A in FIG. 3;

FIG. 5 is a schematic perspective view of the front cover of the housing of FIG. 1 with the locking mechanism in a locked position, i.e., the locking mechanism is in a locked position when the sand bed is replaced;

FIG. 6 is an enlarged view of the structure at B in FIG. 5;

FIG. 7 is a schematic view of a portion of the components of FIG. 3 after removal from the housing shell;

FIG. 8 is a structural schematic diagram of the inner gear ring in FIG. 2;

FIG. 9 is a schematic view of the construction of a round sand bed plate, one of the sand beds of the present invention;

FIG. 10 is a cross-sectional view taken along line C-C of FIG. 9;

FIG. 11 is a schematic structural view of the outer ring gear of FIG. 10;

FIG. 12 is a schematic view of the construction of a triangular sand bed plate, one of the sand bed plates of the present invention;

FIG. 13 is a cross-sectional view taken along line D-D of FIG. 12;

FIG. 14 is a schematic structural view of a square sand floor, one of the sand floors of the present invention;

FIG. 15 is a cross-sectional view taken along line E-E of FIG. 14;

fig. 16 is an exploded view of three sand floor connection modes of the present invention.

The reference numbers in the above figures are as follows:

the device comprises a shell 1, a front cover 11, a shell 12 and a swing bracket 13; motor 2, motor shaft 21; the cooling fan comprises a connecting shaft 3, a shaft main body 3-1, a circular ring protruding part 3-2, a connecting shaft supporting bearing 31, a cooling fan blade 4, a locking mechanism 5, a locking ring 51, a locking pin 52, a locking pin button 53 and a return spring 54; the dust collection assembly 6, a dust collection fan blade 61, a wind collection cover 62 and a dust outlet 63; an inner gear ring 7; the sand bottom plate 8, the bottom plate 81, the bracket 82, the eccentric block supporting bearing 83, the eccentric block 84, the shaft connecting hole 84-1, the outer gear ring 85, the screw hole 86 and the positioning column 87; the sand bottom plate is connected with a screw 9.

Detailed Description

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

(example 1)

Referring to fig. 1 to 3, the sander of the present embodiment mainly includes a housing 1, a motor 2, a connecting shaft 3, a cooling fan blade 4, a locking mechanism 5, a dust collection assembly 6, an inner gear ring 7, a sand bottom plate 8, and a sand bottom plate connecting screw 9.

The housing 1 comprises a front cover 11, a housing 12 detachably connected to the front cover 11, and 4 swing brackets 13 integrally or fixedly connected to the housing 1 and disposed in the housing 1. The motor 2 is fixedly arranged in the shell 1, and the motor 2 is provided with a motor shaft 21. The contents described in this paragraph are prior art and will not be described in detail.

Referring to fig. 3, the connecting shaft 3 is a structural member formed by integrally or fixedly connecting a shaft main body 3-1 having a circular rod shape and a circular ring protrusion 3-2 provided on the outer periphery of the middle lower portion of the shaft main body 3-1, the upper end of the shaft main body 3-1 is fixedly connected to the motor shaft 21 and follows the motor shaft 21, a screw hole (not labeled in the drawing) recessed upward from the lower end is provided in the shaft main body 3-1, and a connecting shaft support bearing 31 with which the connecting shaft 3 is provided is rotatably provided in the housing 1.

Unlike the prior art in which only one double-sided blade driven by the motor shaft is provided in the machine body (the upper blade cools the motor, and the lower blade takes on the dust collection function during operation), in this embodiment, the cooling blade 4 and the dust collection blade 61 of the dust collection assembly 6 are provided separately. The cooling fan blade 4 is fixedly arranged on the motor shaft 21 and is arranged close to the motor 2, and compared with the mode that the double-sided fan blade bearing two functions cannot be arranged close to the motor 2 in the prior art, the cooling fan blade 4 of the embodiment has a better heat dissipation effect on the motor 2 during working, and the service life of the motor 2 is prolonged.

Referring to fig. 2 to 7, the locking mechanism 5 is used for locking the connecting shaft 3 against rotation when installing or replacing the sand bed plate 8. The locking mechanism 5 comprises a locking ring 51, a locking pin 52, a locking pin button 53 and a return spring 54; the locking ring 51 is a circular structural member, a group of radial inward-concave slotted holes are arranged on the periphery of the locking ring 51 at intervals to serve as pin holes, and the locking ring 51 is fixedly arranged on the connecting shaft 3 and is positioned below the cooling fan blades 4. The lock pin 52 is a rod-shaped structural member matched with the pin hole of the lock ring 51, the lock pin button 53 is a plate member, the outer end of the lock pin 52 is integrally or fixedly connected with the lock pin button 53, and the return spring 54 is used for driving the inner end of the lock pin 52 to automatically recover to a disengaged state from an inserted and locked state with the pin hole of the lock ring 51 after the lock pin button 53 is released. A latch 52 and a return spring 54 are movably disposed within the housing 1, and a latch button 53 is movably disposed on the housing 1.

The dust suction assembly 6 is used for sucking the working dust in the use process of the sander of the embodiment. The dust collection component 6 comprises a dust collection fan blade 61, a wind collection cover 62 and a dust outlet 63; the dust collection fan blades 61 are self-suction fan blades, the dust collection fan blades 61 are fixedly arranged on the connecting shaft 3, and the dust collection fan blades are arranged on the lower side of the connecting shaft 3 and close to the sand bottom plate 8. The wind collecting cover 62 is a cylindrical structure, the wind collecting cover 62 is fixedly arranged in the housing 1, the dust outlet 63 is arranged on the housing 1, one port of the wind collecting cover 62 is arranged close to the dust collection fan blade 61, and the other port of the wind collecting cover 62 is communicated with the dust outlet 63. Different from the prior art that only one double-sided fan blade driven by a motor rotating shaft is arranged in a machine body (the upper-end fan blade is used for air cooling of the motor, and the lower-end fan blade is used for bearing the dust collection function during working), in the embodiment, the dust collection fan blade 61 and the cooling fan blade 4 are respectively arranged, so that the dust collection fan blade 61 of the embodiment can be arranged closer to the sand bottom plate 8 relative to the prior art, the dust collection efficiency of the dust collection fan blade can reach more than 3 times of the prior art, the dust collection effect is better, and the dust collection fan blade is beneficial to the health of operators and improves the working quality.

The inner gear ring 7 is used for auxiliary positioning when the sand bottom plate 8 is installed or replaced; the structure of the ring gear 7 is shown in fig. 8. The inner gear ring 7 is fixedly connected with the lower end face of the circular ring protrusion 3-2 of the connecting shaft 3 through one opening end thereof, and the lower end of the shaft main body 3-1 of the connecting shaft 3 penetrates through the inner gear ring 7 to extend downwards.

Referring to fig. 9 to 16, the sand bottom plate 8 mainly comprises a bottom plate 81, a bracket 82 fixedly arranged at the upper end of the bottom plate 81, an eccentric block supporting bearing 83 arranged in the bracket 82, an eccentric block 84 rotatably sleeved with an inner ring of the eccentric block supporting bearing 83, and an outer gear ring 85 fixedly arranged at the periphery of the upper end of the eccentric block 84 and used for being matched with the inner gear ring 7 to be inserted and positioned in an auxiliary manner when the sand bottom plate 8 is installed. The eccentric block 84 is provided with a shaft connecting hole 84-1 which is through up and down; the middle of the bottom plate 81 is provided with a screw hole 86 which is vertically communicated and is used for being matched with the sand bottom plate connecting screw 9 to fix the sand bottom plate 8, and the position of the screw hole 86 is matched with the position of the shaft connecting hole 84-1 of the eccentric block 84. In use, sandpaper (not shown) is fixedly disposed on the lower end surface of the bottom plate 81. The sand bed 8 is different in the shape of the bottom plate 81, and examples of the sand bed 8 in this embodiment include a round sand bed, a triangular sand bed, and a square sand bed. As is well known in the art, the circular sand bottom plate rotates during operation, and the triangular sand bottom plate and the square sand bottom plate swing during operation, so that when the triangular sand bottom plate or the square sand bottom plate is used as the

sand bottom plate

8, 4 positioning posts 87 which are inserted into and engaged with 4 swing brackets 13 fixedly arranged in the housing 1 are respectively arranged on the brackets 82, which is the same as the prior art and will not be described in detail. In this embodiment, when the sand bottom plate 8 is a round sand bottom plate, a triangular sand bottom plate, or a square sand bottom plate, the structure and shape of the eccentric block 84 are respectively designed to optimize vibration and noise in conformity with the shape of the sand bottom plate 8. When the sand bottom plate 8 is installed, firstly, the lock pin button 53 of the locking mechanism 5 is pressed to enable the lock pin 52 to be inserted into the lock ring 51 so as to lock the connecting shaft 3 to be incapable of rotating (as shown in fig. 6), then the outer gear ring 85 of the sand bottom plate 8 is sleeved with the inner gear ring 7, at the moment, the lower end of the connecting shaft 3 is inserted into the shaft connecting hole 84-1 of the eccentric block 84, the sand bottom plate connecting screw 9 penetrates through the screw hole 86 in the middle of the bottom plate 81 from bottom to top, the sand bottom plate connecting screw 9 is matched and screwed with the screw hole of the shaft main body 3-1 of the connecting shaft 3, when the sand bottom plate 8 is a triangular sand bottom plate and a square sand bottom plate, 4 positioning columns 87 are inserted into the 4 swing supports 13 in the shell 1 when the outer gear ring 85 is sleeved with the inner gear ring 7, so that the three sand bottom plates 8 can be installed, and finally, the lock pin button 53 of the locking mechanism 5 is pressed to enable the lock pin 52 to be loosened from the lock ring 51 (as shown in fig. 4) under the action of the reset spring 54 so as to enable the connecting The shaft 3 can rotate, and the sander can be used. When the sand bed plate 8 needs to be replaced, the sand bed plate 8 is removed in a reverse order of the above-described mounting operation. Can know by the aforedescribed, its sand bottom plate 8 of grinder of this embodiment is when installation and change, convenient operation is swift, labour saving and time saving, and installation and change sand bottom plate 8 efficiency are higher to can solve among the prior art sand bottom plate generally through 4 screws with locate 4 screw holes that connecting seat fixed connection exists in the fuselage align to fix a position the more difficult, change the lower technical problem of sand bottom plate efficiency of screw.

The grinder of this embodiment is because locate eccentric block 84 in the sand bottom plate 8, consequently can adopt the optimal structural design of adaptability to the sand bottom plate 8 of different shapes, thereby can reduce vibrations and the noise of grinder when using by a wide margin, can effectively solve among the prior art only fixed 1 eccentric block that sets up in the motor shaft can not the best adaptation simultaneously circular, triangle-shaped, square sand bottom plate and make the grinder shake greatly at the during operation, the noise is big, the operator feels poor, long-time during operation influences the healthy technical problem of work efficiency and operator's body and mind.

The above embodiments are illustrative of specific embodiments of the present invention, and are not restrictive of the present invention, and those skilled in the relevant art can make various changes and modifications without departing from the spirit and scope of the present invention to obtain corresponding equivalent technical solutions, and therefore all equivalent technical solutions should be included in the scope of the present invention.

Claims

1. The utility model provides a sander, includes the shell, fixes locating motor that has a motor shaft in the shell is located the shell below by motor drive's sand bottom plate, its characterized in that: the sand bottom plate fixing device comprises a sand bottom plate, a motor shaft, a connecting shaft, a cooling fan blade, a locking mechanism, a dust collection assembly, an inner gear ring and 1 sand bottom plate connecting screw, wherein the connecting shaft is fixedly connected with the motor shaft; the sand bottom plate comprises an eccentric block arranged inside and an outer gear ring matched with the inner gear ring; the outer gear ring is fixedly arranged on the periphery of the upper end of the eccentric block; when the sand bottom plate is installed, the outer gear ring is sleeved with the inner gear ring, the eccentric block of the sand bottom plate is inserted into the connecting shaft, and the sand bottom plate is fixedly connected with the connecting shaft through the sand bottom plate connecting screw.

2. The sander as set forth in claim 1, wherein: the connecting shaft is a structural part formed by integrally or fixedly connecting a round rod-shaped shaft main body and a circular ring protruding part arranged on the periphery of the middle lower part of the shaft main body, the connecting shaft is fixedly connected with the motor shaft from the upper end of the shaft main body, a screw hole which is upwards recessed from the lower end face is arranged in the shaft main body, and the connecting shaft is rotatably arranged in the shell by a connecting shaft supporting bearing arranged on the connecting shaft; the sand bottom plate connecting screw is matched with a screw hole of the shaft main body of the connecting shaft; the inner gear ring is fixedly connected with the lower end face of the circular ring protruding part of the connecting shaft.

3. The sander as set forth in claim 1, wherein: the locking mechanism comprises a locking ring, a locking pin button and a return spring; the locking ring is a structural member which is circular as a whole, a group of radial inwards concave slotted holes are arranged at intervals on the periphery of the locking ring and are used as pin holes, and the locking ring is fixedly arranged on the connecting shaft and is positioned below the cooling fan blades; the lock pin is a rod-shaped structural member matched with the pin hole of the lock ring, the lock pin button is a plate body member, the outer end of the lock pin is integrally or fixedly connected with the lock pin button, and the reset spring is used for driving the inner end of the lock pin to automatically recover to a separation state from an insertion locking state with the pin hole of the lock ring after the lock pin button is loosened; the lock pin and the reset spring are movably arranged in the shell, and the lock pin button is movably arranged on the shell.

4. The sander as set forth in claim 1, wherein: the dust collection component comprises dust collection fan blades, a wind collection cover and a dust outlet nozzle; the dust collection fan blade is fixedly arranged on the lower side of the connecting shaft and is close to the sand bottom plate; the air collecting cover is a cylindrical structural member, the air collecting cover is fixedly arranged in the shell, and the dust outlet is arranged on the shell; one port of the air collecting cover is arranged close to the dust collection fan blade, and the other port of the air collecting cover is communicated with the dust outlet nozzle.

5. The sanding machine according to any one of claims 1 to 4, characterized in that: the sand bottom plate also comprises a bottom plate, a bracket fixedly arranged at the upper end of the bottom plate, and an eccentric block supporting bearing fixedly arranged in the bracket, wherein the eccentric block is rotatably sleeved with an inner ring of the eccentric block supporting bearing, the eccentric block is provided with a shaft connecting hole which is vertically communicated, the middle part of the bottom plate is provided with a screw hole which is vertically communicated and is matched with the shaft connecting hole of the eccentric block, and the integral structure and the shape of the eccentric block are matched with the shape of the bottom plate; the eccentric block is inserted into the connecting shaft through a shaft connecting hole of the eccentric block and fixedly connected with the connecting shaft through a screw hole of the sand bottom plate connecting screw penetrating through the bottom plate.

6. The sander as set forth in claim 5, wherein: the bottom plate of the sand bottom plate is a circular plate member, and correspondingly, the sand bottom plate is a circular sand bottom plate.

7. The sander as set forth in claim 5, wherein: the bottom plate of the sand bottom plate is a triangular plate or a square plate, and correspondingly, the sand bottom plate is a triangular sand bottom plate or a square sand bottom plate; the shell also comprises 4 swing brackets which are integrated with the shell or fixedly connected with the shell and arranged in the shell; triangle sand bottom plate and square sand bottom plate all still include fixedly or locate integratively 4 reference columns on the support, during the installation 4 reference columns correspond with 4 swing bracket of shell and peg graft.