Sander

Abstract

The utility model provides a kind of sander, comprising: shell;Motor, is housed in shell, with motor shaft;Base, it is connected to the end side of motor shaft, and it is moved under the driving of motor shaft. Among them, base includes: bottom plate;Base bearing chamber, it is set to bottom plate and extends towards motor, base bearing chamber includes the first wall surface and the second wall surface of interval arrangement, the first wall surface is surrounded in the radial outer side of second wall surface;Insert, and integrally formed with base, insert is completely located in base;Insert has base plate and annular part, annular part is between the first wall surface and the second wall surface, annular part is arranged with base plate angle and extends towards motor.

Description

Technical Field

[0001] This utility model relates to an electric tool, and more particularly to a sander used in decoration, construction and other applications. Background Technology

[0002] A sander is a type of power tool mainly used for everyday furniture grinding and steel polishing. The motor of the sander, through an eccentric component and a base bearing, can convert the rotational motion of the motor shaft itself into the eccentric track motion of the base, thereby driving the sandpaper and other top attachments mounted on the base to process the workpiece.

[0003] However, during sanding machine operation, the centrifugal force from the base, sandpaper, etc., is transmitted to the base bearing through the base bearing housing, subjecting the bearing housing to alternating stress. Simultaneously, to prevent bearing slippage, a large interference fit is typically used between the bearing housing and the bearing, which exacerbates the stress on the bearing housing. Therefore, given the limited strength of the base material itself, the bearing housing is prone to cracking at the opening under stress concentration. This undoubtedly affects the normal operation of the sander and, in severe cases, poses a safety risk.

[0004] Therefore, it is determined that it is necessary to provide an improved sander to overcome the shortcomings of the existing technology. Utility Model Content

[0005] In view of the shortcomings of the existing technology, the purpose of this utility model is to provide a sander that increases the strength of the base.

[0006] The present invention can solve the existing technical problems by adopting the following technical solution:

[0007] A sander, comprising:

[0008] case;

[0009] An electric motor, housed within the housing, the electric motor having a motor shaft;

[0010] A base is connected to the end of the motor shaft and moves under the drive of the motor shaft;

[0011] The base includes:

[0012] Base plate;

[0013] A base bearing chamber is disposed on the base plate and extends toward the motor. The base bearing chamber includes a first wall and a second wall spaced apart, with the first wall surrounding the radially outer side of the second wall.

[0014] An insert, wherein the insert and the base are integrally formed, and the insert is completely located within the base;

[0015] The insert has a substrate and an annular portion, the annular portion being located between the first wall surface and the second wall surface, the annular portion being angled to the substrate and extending toward the motor.

[0016] A further improvement is that the annular portion is perpendicular to the substrate and extends toward the motor;

[0017] A reinforcing rib is connected between the base and the first wall surface, the annular portion is located radially inside the reinforcing rib, and the base plate extends beyond the radially outer end of the reinforcing rib.

[0018] A further improvement is that the substrate has a plurality of openings spaced apart, and the included angle between two adjacent openings is 90°.

[0019] A further improvement is as follows: the upper surface of the base is provided with a protrusion, the protrusion abuts against the first wall surface, and the protrusion is located between the reinforcing ribs in the circumferential direction.

[0020] A further improvement is as follows: a fan is provided on the end side of the motor shaft near the base. The fan includes a base, a first fan blade, a second fan blade, and an eccentric part. The first fan blade is located on the side of the base facing the motor, the second fan blade is located on the side of the base facing the base, and the eccentric part is connected to the motor shaft and extends into the bearing chamber of the base.

[0021] The motor shaft has a first axis, and the eccentric part has a second axis parallel to the first axis. The motor shaft drives the base to move eccentrically around the first axis.

[0022] A further improvement is as follows: the housing includes a motor housing, a handle housing, and an end housing, with the motor housing located between the handle housing and the end housing;

[0023] A vibration frame is provided between the end housing and the base, and the vibration frame restricts the rotational movement of the base about the second axis.

[0024] A further improvement is as follows: the base has a fixing part, a clamping part, and a top attachment, the clamping part being pivotally mounted on the fixing part so that the top attachment can be attached to or detached from the base.

[0025] A further improvement is as follows: the first fan blade is used to generate the cooling airflow, and the second fan blade is used to block dust generated by the operation of the top accessory from entering the motor.

[0026] A further improvement is as follows: the base bearing chamber houses the base bearing, the eccentric portion extends into the base bearing, and a dustproof component is provided between the base bearing and the base bearing chamber.

[0027] A further improvement is that the base bearing is located between the fan and the base.

[0028] Compared with the prior art, the present invention has the following beneficial effects:

[0029] An insert is added between the first and second walls of the bearing chamber of the sander base, which improves the strength of the bearing chamber and reduces the risk of cracking at the opening due to concentrated stress. At the same time, the insert is assembled as an integral part of the base, which simplifies the assembly process. Attached Figure Description

[0030] Figure 1 This is a schematic diagram of the sander in the embodiment of this utility model;

[0031] Figure 2 for Figure 1 A cross-sectional view of the sander shown;

[0032] Figure 3 for Figure 2 The diagram shows the structure of the base in the sander.

[0033] Figure 4 for Figure 3 A cross-sectional view of the base shown;

[0034] Figure 5 for Figure 4 A schematic diagram of the structure of the insert in the base is shown;

[0035] Figure 6 for Figure 5 The diagram shows the insert being assembled onto the base. Detailed Implementation

[0036] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments.

[0037] The terminology used in this invention is for the purpose of describing specific embodiments only and is not intended to limit the invention. For example, terms such as "upper," "lower," "front," "rear," "left," and "right," which indicate orientation or positional relationship, are based solely on the orientation or positional relationship shown in the accompanying drawings and are used only for the convenience of describing the invention and simplifying the description. They do not indicate or imply that the device / component referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore should not be construed as limiting the invention.

[0038] Please see Figures 1 to 3As shown, the embodiment of this utility model relates to a sander 100, including a housing 1, a motor 2 installed in the housing 1, a fan 3 connected to the motor 2, and a base 4 driven by the motor 2. The housing 1 includes a motor housing 11 that houses the motor 2, a handle housing 12 and an end housing 13 connected to the motor housing 11. The motor housing 11 is located between the handle housing 12 and the end housing 13, that is, the end housing 13 is located between the motor housing 11 and the base 4. When operating the sander 100, the user can hold the handle housing 12 with one hand and the motor housing 12 with the other hand, so that the top attachment 5 installed on the base 4 acts on the workpiece. The top attachment 5 can be sandpaper, sanding pad, etc.

[0039] Please continue reading. Figures 1 to 3 The motor 2 has a first axis X and a motor shaft 21 that rotates around the first axis X. Specifically, the motor shaft 21 is supported on the handle housing 12 by a first bearing 121 and on the end housing 13 by a second bearing 131, and extends through the end housing 13. A fan 3 is installed at the portion of the motor shaft 21 that protrudes from the end housing 13. The fan 3 includes a base 31, a first fan blade 32, a second fan blade 33, and an eccentric portion 34. The first fan blade 32 is located on the side of the base 31 facing the motor 2, the second fan blade 33 is located on the side of the base 31 facing the base 4, and the eccentric portion 34 is located radially inward of the second fan blade 33 and connected to the motor shaft 21. The eccentric portion 34 has a second axis L parallel to the first axis X, and the first axis X and the second axis L are spaced apart from each other.

[0040] The base 4 is connected to the lower end of the motor shaft 21 by fasteners such as screws. The base 4 has a base plate 40, and a base bearing chamber 41 is formed at the center of the upper surface of the base plate 40. An eccentric portion 34 extends into the base bearing chamber 41. A base bearing 42 is also provided in the base bearing chamber 41 and is interference-fitted with it. The eccentric portion 34 extends into the base bearing 42.

[0041] Please continue reading. Figures 1 to 3 When the sander 100 is working, the motor shaft 21 drives the fan 3 to rotate. The first fan blade 32 rotates to generate cooling airflow. The cooling airflow flows in from the air inlet 12a on the outer surface of the handle housing 12, flows through the motor 2 for heat dissipation, and then flows out from the exhaust port 11a on the outer surface of the motor housing 11. During this process, since the top attachment 5 generates a lot of dust when grinding the workpiece, in order to prevent the dust from entering the motor 2 from the end housing 13 as much as possible, the second fan blade 33 will intercept the dust when rotating. Preferably, the radial dimension of the second fan blade 33 is approximately equal to the radial dimension of the first fan blade 32 to maximize the dustproof area.

[0042] Dust can enter the motor from the end housing 13 and also enter the base bearing chamber 41 through the base 4. Therefore, the second fan blade 33 should cover the base bearing chamber 41 radially to form a labyrinth-like dustproof structure, making it difficult for dust to enter the base bearing chamber 41 and corrode the base bearing 42. In addition, a dustproof pad is provided between the base bearing 42 and the base bearing chamber 41 to prevent dust from entering the gap between them and causing the interference fit to fail.

[0043] It should be noted that in this embodiment, the base 4 is not completely free to move; its movement is restricted. Please refer to... Figure 2 A vibration frame 6 is connected between the end housing 13 and the base 4. The function of the vibration frame 6 is to restrict the rotational movement of the base 4 around the second axis L when the base 4 follows the motor shaft 21 to perform eccentric track movement around the first axis X. That is, the rotational movement of the base 4 itself will be restricted by the vibration frame.

[0044] When the user finishes working and needs to replace the top accessory 5, the clamping part 43 installed on the base 4 can be released, thereby removing the top accessory 5 from the base 4. Furthermore, after replacing the top accessory 5, the user can re-clamp the clamping part 43 to reposition the top accessory 5. In this embodiment, the clamping part 43 is a wire clamp, which is pivotally mounted in the fixing parts 44 at both ends of the base 4.

[0045] Furthermore, during the eccentric track movement, the base 4 itself and the top attachment 5 apply alternating stress to the base bearing chamber 41. This may cause cracking at the opening of the base bearing chamber 41. Therefore, in this embodiment, an insert 7 is added to the base bearing chamber 41. Please refer to... Figures 3 to 5 The base bearing chamber 41 is generally annular, including a first wall 411 located on the outer radial side and a second wall 412 located on the inner radial side. The insert 7 includes a base plate 71 and an annular portion 72. The base plate 71 and the base 4 are arranged in parallel, and the annular portion 72 extends perpendicularly to the base plate 71 toward the motor 2.

[0046] Specifically, a reinforcing rib 45 connects the base 4 and the first wall surface 411. An annular portion 72 is located between the first wall surface 411 and the second wall surface 412. The base plate 71 extends horizontally beyond the radial outer end of the reinforcing rib 45. Thus, by adding an insert 7 to the base bearing chamber 41, the strength of the base bearing chamber 41 can be improved. It should be noted that the material of the insert 7 should be different from that of the base 4. In this embodiment, the material of the base 4 is PC+GF20, and the material of the insert 7 is Q235. By transferring part of the alternating stress on the base bearing chamber 4 to the insert 7, the risk of cracking and failure of the base bearing chamber 41 can be reduced. Furthermore, a protrusion 46 is provided between the reinforcing ribs 45, and the protrusion 46 abuts against the bottom of the first wall surface 411, which can further improve the strength of the base bearing chamber 41.

[0047] Please see Figures 4 to 6 The insert 7 and the base 4 are integrally molded. Once the insert 7 is injection molded onto the base 4, it cannot be removed. The process of installing the insert 7 onto the base 4 will be described below. In this embodiment, the insert 7 needs to be pre-processed. The portion of the substrate 71 that exposes the annular portion 72 is formed by flanging the annular portion 72. To prevent wrinkles from forming on the flanging, a number of openings 73 are provided on the substrate 71. The number of openings 73 can be four or six, but four is preferred here. Therefore, the included angle between any two adjacent openings 73 is 90°.

[0048] Furthermore, to achieve a seamless connection between insert 7 and base 4, a mold is required. (Go to...) Figure 6 The mold consists of a fixed mold 8 and a movable mold (not shown). The insert 7 is placed on the fixed mold 8, and the insert 7 can be limited in the circumferential and radial directions by means of the jaws 81. At the same time, the movable mold has a limiting rod 82, which abuts against the base plate 71 of the insert 7 to limit the axial direction of the insert 7. Since the cavity between the fixed mold 8 and the movable mold has been machined to form the shape of the base 4, it is only necessary to fill the cavity with glue. In this way, the insert 7 is fixed in the base 4, and the two are combined into a single part.

[0049] Those skilled in the art will readily understand that many other alternatives to the sander of this invention exist without departing from the principles and scope of this invention. The scope of protection of this invention is defined by the claims.

Claims

1. A sander, comprising: case; An electric motor, housed within the housing, the electric motor having a motor shaft; A base is connected to the end of the motor shaft and moves under the drive of the motor shaft; The base is characterized in that it comprises: Base plate; A base bearing chamber is disposed on the base plate and extends toward the motor. The base bearing chamber includes a first wall and a second wall spaced apart, with the first wall surrounding the radially outer side of the second wall. An insert, wherein the insert and the base are integrally formed, and the insert is completely located within the base; The insert has a substrate and an annular portion, the annular portion being located between the first wall surface and the second wall surface, the annular portion being angled to the substrate and extending toward the motor.

2. The sander according to claim 1, characterized in that: The annular portion is perpendicular to the substrate and extends toward the motor; A reinforcing rib is connected between the base and the first wall surface, the annular portion is located radially inside the reinforcing rib, and the base plate extends beyond the radially outer end of the reinforcing rib.

3. The sander according to claim 2, characterized in that: The substrate has a plurality of openings spaced apart, and the included angle between two adjacent openings is 90°.

4. The sander according to claim 3, characterized in that: The upper surface of the base is provided with a protrusion, which abuts against the first wall surface and is located between the reinforcing ribs in the circumferential direction.

5. The sander according to claim 1, characterized in that: A fan is provided on the end side of the motor shaft near the base. The fan includes a base, a first fan blade, a second fan blade, and an eccentric part. The first fan blade is located on the side of the base facing the motor, the second fan blade is located on the side of the base facing the base, and the eccentric part is connected to the motor shaft and extends into the bearing chamber of the base. The motor shaft has a first axis, and the eccentric part has a second axis parallel to the first axis. The motor shaft drives the base to move eccentrically around the first axis.

6. The sander according to claim 5, characterized in that: The housing includes a motor housing, a handle housing, and an end housing, with the motor housing located between the handle housing and the end housing; A vibration frame is provided between the end housing and the base, and the vibration frame restricts the rotational movement of the base about the second axis.

7. The sander according to claim 5, characterized in that: The base has a fixing part, a clamping part, and a top attachment, wherein the clamping part is pivotally mounted on the fixing part so that the top attachment can be attached to or detached from the base.

8. The sander according to claim 7, characterized in that: The first fan blade is used to generate cooling airflow, and the second fan blade is used to prevent dust generated during the operation of the top accessory from entering the motor.

9. The sander according to claim 5, characterized in that: The base bearing chamber houses the base bearing, the eccentric portion extends into the base bearing, and a dustproof pad is provided between the base bearing and the base bearing chamber.

10. The sander according to claim 6, characterized in that: The base bearing is located between the fan and the base.

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