Ball motor

Abstract

The utility model belongs to the technical field of camera module lens driving devices, and discloses a ball motor, which comprises a movable part, a fixed part, a driving part and balls, the movable part can move relative to the fixed part under the action of the driving part, the fixed part and the movable part are respectively provided with a first ball rail groove body and a second ball rail groove body, and the first ball rail groove body and the second ball rail groove body are arranged in parallel. The ball is clamped between the first ball rail groove body and the second ball rail groove body and can roll in the first ball rail groove body and the second ball rail groove body when the movable part moves relative to the fixed part, and at least one of the first ball rail groove body and the second ball rail groove body can provide buffering for the ball through elastic deformation. And the possibility of plastic deformation such as pits formed after the ball motor is impacted by external force is reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of camera module lens driving devices, in particular to a ball motor. Background Art

[0002] During the imaging process of a camera module, in order to better improve the imaging quality of the camera module, a corresponding drive device can be configured in the camera module structure to drive the optical lens to move along the optical axis to obtain a clearer image. In the prior art, the drive device generally selected is a motor structure, such as a ball motor, SMA motor, or piezoelectric motor structure.

[0003] Ball bearing motors require track grooves to allow the balls to move in the direction defined by the grooves. However, the track grooves are typically made of plastic, which is less rigid than the balls. This can easily lead to permanent deformation due to stress damage after reliability testing (including physical tests like dropping), affecting the ball bearing's trajectory. Utility Model Content

[0004] The purpose of the utility model is to provide a ball motor that can effectively avoid plastic deformation of the track structure and ensure the reliability of the ball movement track.

[0005] To achieve this purpose, the present invention adopts the following technical solutions:

[0006] A ball motor includes a fixed part, a movable part and a ball, wherein the fixed part is provided with a first ball track groove body; the movable part is provided with a second ball track groove body; the ball is clamped between the first ball track groove body and the second ball track groove body, and the movable part can move relative to the fixed part under the drive of the driving part. When the movable part moves relative to the fixed part, the ball rolls in the first ball track groove body and the second ball track groove body, and at least one of the first ball track groove body and the second ball track groove body can provide cushioning for the ball through elastic deformation.

[0007] In one embodiment, a cavity is provided in the first ball rail groove.

[0008] In one embodiment, the cavity is configured in a honeycomb shape.

[0009] In one embodiment, the cavity is filled with an elastomer.

[0010] In one embodiment, the cavity wall is configured as a sawtooth structure.

[0011] In one embodiment, the elastic body is formed and filled into the cavity, and the cavity penetrates the fixed portion at two opposite sides along the moving direction of the movable portion.

[0012] In one embodiment, the cavity has an opening communicating with the outside, and the elastomer is formed by solidifying a liquid in the cavity.

[0013] In one embodiment, the first ball track groove body includes a main body and a track portion, the track portion is connected to the main body via an elastic member, and the ball is clamped between the track portion and the second ball track groove body.

[0014] In one embodiment, the elastic member includes a spring sheet, a mounting groove is formed on a side of the main body facing the first ball rail groove body, and the spring sheet is located in the mounting groove and spaced apart from the bottom of the mounting groove.

[0015] In one embodiment, the spring piece is plugged and fixed to the rail portion.

[0016] Beneficial effects of the utility model:

[0017] The balls on the ball motor proposed in the embodiment of the present invention can move along the direction of the optical axis of the lens under the restriction of the first ball track groove body and the second ball track groove body. When subjected to external force impact, at least one of the first ball track groove body and the second ball track groove body can provide buffering elastic force to the balls, reducing the possibility of plastic deformation such as pits in the first ball track groove body and the second ball track groove body, and improving the accuracy and reliability of the ball movement direction. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is a schematic structural diagram of a ball motor in an embodiment of the present invention;

[0019] Figure 2 This is a diagram showing the positional relationship between the movable portion and the fixed portion in an embodiment of the present utility model;

[0020] Figure 3 is a cross-sectional view of a ball motor in one embodiment of the present invention;

[0021] Figure 4 is a cross-sectional view of a ball motor in another embodiment of the present invention;

[0022] Figure 5 yes Figure 4 A cross-sectional view of the first ball rail groove body in the embodiment of FIG.

[0023] Figure 6 This is a cross-sectional view of a ball motor in another embodiment of the present invention;

[0024] Figure 7 yes Figure 6 A cross-sectional view of the first ball rail groove body in the embodiment of FIG.

[0025] Figure 8 It is a schematic diagram of the structure of the shrapnel.

[0026] In the picture:

[0027] 1. Fixed part; 11. First ball rail groove body; 111. Cavity; 112. Elastomer; 113. Spring piece; 1131. Insertion hole; 1132. Strip notch; 114. First ball rail groove; 115. Main body; 1151. Mounting groove; 1152. Limiting groove; 116. Track part; 1161. Insert block; 2. Movable part; 21. Second ball rail groove body; 211. Second ball rail groove; 3. Ball; 4. Housing. DETAILED DESCRIPTION

[0028] The present invention will be further described in detail below with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described herein are intended only to illustrate the present invention and are not intended to limit the present invention. It should also be noted that, for ease of description, the accompanying drawings only illustrate portions relevant to the present invention, not all of its components.

[0029] In the description of this utility model, unless otherwise specified or limited, the terms "connected," "connect," and "fixed" should be understood in a broad sense. For example, they can refer to fixed connection, detachable connection, or integration; mechanical connection or electrical connection; direct connection or indirect connection through an intermediate medium; internal communication between two components or interaction between two components. Those skilled in the art will understand the specific meanings of the above terms in this utility model based on the specific circumstances.

[0030] In the present invention, unless otherwise expressly specified or limited, a first feature being "above" or "below" a second feature may include the first and second features being in direct contact, or may include the first and second features being in contact not directly but through another feature between them. Moreover, a first feature being "above," "above," and "above" a second feature may include the first feature being directly above or obliquely above the second feature, or may simply mean that the first feature is higher in level than the second feature. A first feature being "below," "below," and "below" a second feature may include the first feature being directly below or obliquely below the second feature, or may simply mean that the first feature is lower in level than the second feature.

[0031] In the description of this embodiment, the terms "upper," "lower," "right," and other orientations or positional relationships are based on the orientations or positional relationships shown in the accompanying drawings and are intended solely for ease of description and simplified operation. They do not indicate or imply that the devices or components referred to must have a specific orientation, be constructed, or operate in a specific orientation. Therefore, they should not be construed as limitations on the present invention. Furthermore, the terms "first" and "second" are used solely for descriptive purposes and have no special meaning.

[0032] refer to Figures 1-8 As shown, the ball motor includes a housing 4, a movable part 2, a fixed part 1, a driving part and a ball 3, wherein the driving part includes a magnet and a coil, the magnet is arranged on the movable part 2, and the coil is arranged on the fixed part 1. When the coil is energized, the movable part 2 can drive the lens located thereon to move relative to the fixed part 1 along the optical axis direction of the lens, thereby obtaining a clearer image. The ball 3 is arranged between the movable part 2 and the fixed part 1 to reduce the friction when the movable part 2 moves relative to the fixed part 1. The housing 4 covers the movable part 2, the fixed part 1, the driving part and the ball 3 to protect the above components.

[0033] In order to limit the movement path of the ball 3 so that the ball 3 moves along the optical axis of the lens, a first ball track groove body 11 and a second ball track groove body 21 are respectively provided on the fixed part 1 and the movable part 2, and a first ball track groove 114 and a second ball track groove 211 with opposite notches are respectively opened on the first ball track groove body 11 and the second ball track groove body 21. The ball 3 is clamped between the first ball track groove body 11 and the second ball track groove body 21. When the movable part 2 moves relative to the fixed part 1, the ball 3 rolls in the first ball track groove 114 of the first ball track groove body 11 and the second ball track groove body 21, thereby causing the movable part 2 to move relative to the fixed part 1 along the optical axis of the lens. It should be emphasized here that at least one of the first ball track groove body 11 and the second ball track groove body 21 can provide a buffer for the ball 3 through elastic deformation, so as to reduce the possibility of pits being generated in the first ball track groove body 11 and the reduction in the movement accuracy of the ball 3 when the ball motor is impacted by external force.

[0034] In one embodiment, a cavity 111 is provided within the first ball track groove 11. Cavity 111 is located on the side of the first ball track groove 114 facing away from the second ball track groove 21 and aligned with the first ball track groove 114. The provision of cavity 111 enables the first ball track groove 11 to provide elastic force to the ball 3. It is understood that cavity 111 can be enclosed or have an opening extending through the surface of the fixing portion 1 to communicate with the outside.

[0035] In order to provide better buffering, the size of the cavity 111 is designed according to the size of the first ball track groove 114 so that the orthographic projection of the first ball track groove 114 toward the cavity 111 falls completely within the area where the cavity 111 is located, thereby allowing the cavity 111 to cover the entire first ball track groove 114 .

[0036] It is understandable that the cavity 111 can be a completely hollow structure or a honeycomb structure, that is, composed of a plurality of hollow structures arranged at intervals, so as to provide the best buffering effect.

[0037] In one embodiment, the cavity 111 is filled with an elastomer 112 with good buffering ability. The elastomer 112 can further absorb external impact on the first ball rail groove body 11, reduce stress concentration, prevent the first ball rail groove body 11 from plastic deformation, and thus reduce possible pitting.

[0038] Specifically, to provide better cushioning capability, the elastic body 112 is completely in contact with the wall of the cavity 111. It is understood that the elastic body 112 can be formed first and then filled into the cavity 111, or can be filled into the cavity 111 first and then formed.

[0039] For example, the elastomer 112 is first formed and then filled into the cavity 111. At this time, the elastomer 112 can be made of silicone, which has high resilience and durability, is resistant to high temperatures, and is resistant to aging; the elastomer 112 can also be made of TPU (thermoplastic polyurethane elastomer 112), which has good wear resistance and elasticity, and is resistant to low temperatures; the elastomer 112 can also be made of rubber, which has excellent elasticity and wear resistance and is suitable for use in various environments.

[0040] refer to Figure 5 As shown, in order to enable the elastic body 112 to provide a more uniform buffering capability, the cavity 111 passes through two surfaces of the fixed portion 1 that are oppositely arranged along the optical axis direction, that is, along the moving direction of the movable portion 2 .

[0041] Optionally, the cavity wall of the cavity 111 is set to a serrated structure, and correspondingly, the edge of the elastomer 112 is also set to a serrated shape to engage with the cavity wall of the cavity 111, so as to enhance the connection stability between the elastomer 112 and the fixing part 1 and prevent the elastomer 112 from sliding.

[0042] Of course, the elastic body 112 can be filled in the position where the cavity 111 is set in the fixing part 1 when the fixing part 1 is injection-molded, or the elastic body 112 can be stuffed into the cavity 111 after the fixing part 1 is molded.

[0043] Alternatively, the elastomer 112 is solidified by a liquid filled in the cavity 111 or a liquid coated on the groove wall of the cavity 111. For example, the elastomer 112 is a glue layer solidified by silicone glue / PU (polyurethane) glue / acrylic glue / epoxy resin glue, etc. The above glue is filled in the cavity 111 to form the elastomer 112. At this time, the cavity 111 has an opening connected to the outside.

[0044] Silicone glue has strong adhesion, high temperature resistance, and good elasticity; PU glue has strong adhesion, wear resistance, and good elasticity; acrylic glue has strong adhesion and fast curing speed, but relatively poor elasticity. You can choose according to your specific needs.

[0045] In another embodiment, the first ball rail groove body 11 is separately provided, including a main body 115 and a rail portion 116, wherein the main body 115 is used to support the rail portion 116, and the rail portion 116 is located on the side of the main body 115 facing the movable portion 2. The first ball rail groove 114 is opened on the rail portion 116, and the rail portion 116 is movably connected to the main body 115 through an elastic member. The elastic member can provide a buffering elastic force to the rail portion 116 to reduce stress concentration.

[0046] The elastic member can be a spring 113, such as a metal spring or a plastic spring, or a spring. Taking the spring 113 as an example, it is obvious that there is a deformation space between the spring 113 and the main body 115. Figure 5 and 6 As shown, a mounting groove 1151 is defined on one side of the main body 115 facing the track portion 116 , the spring piece 113 is fixed in the mounting groove 1151 and spaced apart from the bottom of the mounting groove 1151 , and the track portion 116 is fixed on the side of the spring piece 113 away from the bottom of the mounting groove 1151 .

[0047] Specifically, to reduce the difficulty of installing the spring piece 113 in the mounting slot 1151, two opposing sides of the mounting slot 1151 are provided with limiting slots 1152 that communicate with the mounting slot 1151. The opening direction of the limiting slots 1152 is aligned with the opening direction of the mounting slot 1151, and the depth of the limiting slots 1152 is less than the depth of the mounting slot 1151. The opposing ends of the spring piece 113 are both installed in the limiting slots 1152. More specifically, to increase the elastic force of the spring piece 113, two opposing sides of the spring piece 113 perpendicular to the direction of movement of the movable portion 2 are provided with strip-shaped notch groups. Each strip-shaped notch group includes two strip-shaped notches 1132 symmetrically arranged along the direction of movement of the movable portion 2. The strip-shaped notches 1132 extend from one edge of the spring piece 113 to the other edge along the direction of movement of the movable portion 2.

[0048] Furthermore, to simplify the connection between the rail portion 116 and the spring clip 113, a socket 1131 is provided on the spring clip 113, and correspondingly, an insert 1161 is provided on the rail portion 116. The rail portion 116 and the spring clip 113 are fixedly connected via the plug-in mating socket 1131 and insert 1161. It is understood that the socket 1131 can be square, circular, or any other shape, and is not specifically limited herein. Of course, the socket 1131 can also be provided on the rail portion 116, while the insert can be provided on the spring clip 113, to ensure plug-in mating between the rail portion 116 and the spring clip 113.

[0049] In other embodiments, the movable portion 2 provided with the second ball rail groove body 21 can be designed according to the principle and structure of the fixed portion 1 that enables the first ball rail groove body 11 to have buffering elasticity, which will not be further described here.

[0050] Obviously, the above-described embodiments of the present invention are merely examples for the purpose of clearly illustrating the present invention and are not intended to limit the manner in which the present invention is to be implemented. A person skilled in the art would be able to make various obvious changes, readjustments, and substitutions without departing from the scope of protection of the present invention. It is not necessary and impossible to enumerate all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the claims of the present invention.

Claims

1. Ball motor, characterized in that: include: A fixing portion (1), wherein the fixing portion (1) is provided with a first ball rail groove body (11); A movable portion (2), wherein the movable portion (2) is provided with a second ball track groove (21); A ball (3) is sandwiched between the first ball track groove body (11) and the second ball track groove body (21); the movable part (2) is capable of moving relative to the fixed part (1) under the drive of a driving part; when the movable part (2) moves relative to the fixed part (1), the ball (3) rolls in the first ball track groove body (11) and the second ball track groove body (21); at least one of the first ball track groove body (11) and the second ball track groove body (21) is capable of providing a buffer for the ball (3) through elastic deformation.

2. The ball motor according to claim 1, wherein: A cavity (111) is provided in the first ball track groove body (11).

3. The ball motor according to claim 2, wherein: The cavity (111) is configured in a honeycomb shape.

4. The ball motor according to claim 2, wherein: The cavity (111) is filled with an elastic body (112).

5. The ball motor according to claim 4, wherein: The cavity wall of the cavity (111) is configured as a sawtooth structure.

6. The ball motor according to claim 4, wherein: The elastic body (112) is formed and filled into the cavity (111), and the cavity (111) passes through the fixed part (1) on two opposite sides along the moving direction of the movable part (2).

7. The ball motor according to claim 4, characterized in that: The cavity (111) has an opening communicating with the outside, and the elastic body (112) is formed by solidifying liquid in the cavity (111).

8. The ball motor according to claim 1, wherein: The first ball track groove body (11) comprises a main body (115) and a track part (116), the track part (116) is connected to the main body (115) through an elastic member, and the ball (3) is sandwiched between the track part (116) and the second ball track groove body (21).

9. The ball motor according to claim 8, characterized in that: The elastic member includes a spring piece (113); a mounting groove (1151) is provided on a side of the main body (115) facing the first ball rail groove body (11); the spring piece (113) is located in the mounting groove (1151) and is spaced apart from the groove bottom of the mounting groove (1151).

10. The ball motor according to claim 9, characterized in that The spring piece (113) is plugged and fixed to the track portion (116).

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