A voice coil motor

Abstract

The utility model discloses a voice coil motor, carrier, which is provided with a first through hole capable of placing a lens, and the side wall of the carrier is fixed with a coil, a base is provided with a second through hole coaxial with the first through hole, a spring piece is arranged between the carrier and the base, and the two sides of the spring piece are fixed with the carrier and the base respectively. The voice coil motor can balance the moment of force by canceling the upper spring and adjusting the lower spring wire width, can perfectly realize the use of one lower spring to carry the carrier, balance the moment of force, produce the tensile force opposite to the magnetic force, realize the use of one spring to realize the AF focusing stroke requirement, thereby reduce the cost.

Description

Technical Field

[0001] This utility model relates to the field of camera module technology, and in particular to a voice coil motor. Background Technology

[0002] In recent years, with the continuous upgrading of mobile terminal imaging capabilities, the autofocus (AF) motor, as a core driving component of the camera module (CCM), has become crucial to the overall competitiveness of the device in terms of performance and cost. Thanks to continuous advancements in manufacturing technology, the production process of camera motors has matured, automation has increased, and the manufacturing cost per unit has shown a downward trend. However, the industry also faces severe dual pressures:

[0003] 1. Weak Market Demand: The global smartphone market has entered a highly mature stage with limited room for growth, and consumers' replacement cycles have significantly lengthened. Authoritative market research data (such as IDC and Canalys) shows that global smartphone shipments have declined year-on-year for several consecutive quarters. The saturation of the terminal market and the shrinking shipments directly impact the upstream supply chain, leading to weak demand growth, and even contraction, for CCM and AF motors.

[0004] 2. Intensified Cost Competition in the Supply Chain: Against the backdrop of weak market demand, terminal brand manufacturers continue to exert enormous pressure on their supply chains to reduce costs in order to maintain competitiveness. As a key selling point for enhancing product differentiation, camera modules are seeing increasingly squeezed room for cost optimization. AF motor suppliers are facing unprecedented price competition, forced to lower product prices to secure increasingly scarce orders, severely compressing the overall profit margins of the industry.

[0005] Faced with these challenges, reducing the Bill of Materials (BOM) cost of AF motors has become a key breakthrough for suppliers to maintain their survival and competitiveness. Traditional AF motor structures (such as spring-loaded VCMs) typically include multiple precision components (generally 10 or more), such as the housing, base, carrier, coil, magnet assembly, upper spring, lower spring, gasket, and insulating sheet. While this structure is mature and reliable, its large number of components, complex assembly process, and high material costs (especially for magnets and precision springs) are becoming increasingly prominent issues. Under intense price competition, the cost reduction potential for traditional structures is very limited, necessitating innovative breakthroughs at the fundamental design level. Utility Model Content

[0006] To address the shortcomings of the existing technology, the technical problem to be solved by this utility model is: to propose a voice coil motor that balances torque by eliminating the upper spring and adjusting the width of the lower spring wire. This allows for the perfect use of a single lower spring to support the carrier, balance torque, and generate a pulling force opposite to the magnetic force, thus achieving the AF focusing stroke requirement with a single spring and reducing costs.

[0007] The technical solution adopted by this utility model is: to provide a voice coil motor, comprising:

[0008] A carrier having a first through hole for placing a lens, and a coil fixed to the side wall of the carrier;

[0009] The base has a second through hole that is coaxial with the first through hole;

[0010] A spring sheet is provided between the carrier and the base, and the two sides of the spring sheet are fixed to the carrier and the base respectively.

[0011] Furthermore, the top of the carrier is uniformly provided with several impact protrusions.

[0012] Furthermore, the number of impact protrusions is eight, and the horizontal cross-section of each impact protrusion is trapezoidal.

[0013] Furthermore, it also includes a housing, on which a third through hole is provided, the third through hole being coaxial with the first through hole and the second through hole; the housing can be fitted and fixed on the base, and enclose the carrier inside it.

[0014] Furthermore, a bar magnet is fixed on each opposite side of the inner wall of the outer casing, and the position of the bar magnet corresponds to that of the coil.

[0015] Furthermore, at least two guide blocks extend from the inner side of the third through hole toward the carrier. A guide hole is provided on the top of the carrier at a position corresponding to the guide block. The guide block can match the guide hole and be inserted into the guide hole.

[0016] Furthermore, a bar magnet is fixed to each of the two opposite sides of the top surface of the base, and the position of the bar magnet corresponds to that of the coil.

[0017] Furthermore, the spring sheet is coaxial with the first through hole and the second through hole; the width of the spring sheet is 0.1mm to 0.24mm.

[0018] Furthermore, the spring sheet is electrically connected to the coil.

[0019] Furthermore, the bottom of the carrier is provided with a plurality of first positioning protrusions, and the top surface of the base is provided with second positioning protrusions at opposite corners. The spring sheet is provided with a first positioning hole and a second positioning hole at positions corresponding to the first positioning protrusions and the second positioning protrusions, respectively. The spring sheet is connected to the carrier through the cooperation of the first positioning hole and the first positioning protrusion, and the spring sheet is connected to the base through the cooperation of the second positioning hole and the second positioning protrusion. The width of the spring sheet is 0.081mm to 0.096mm.

[0020] This utility model discloses a voice coil motor, which has at least the following beneficial effects: 1. By eliminating the upper spring and adjusting the width of the lower spring wire to balance the torque, this solution can perfectly achieve the use of a single lower spring to support the carrier, balance the torque, and generate a pulling force opposite to the magnetic force. This allows the AF focusing stroke requirement to be met with a single spring, thereby reducing costs; 2. The design of bar magnets on both sides of this solution has a relatively simple structure and a regular magnetic field distribution, which can provide a stable driving force. It is suitable for ordinary camera motors with less stringent precision requirements, reducing the number of magnets and lowering the motor's material costs; 3. The impact protrusion design on the carrier of this solution has ample reserved space and a larger impact area, making the force more dispersed when the carrier impacts upward. This results in better product reliability and resistance to impacts, reduces defects caused by impacts with foreign objects, and improves the overall yield. Attached Figure Description

[0021] The accompanying drawings, which are included to provide a further understanding of this application and form part of this application, illustrate exemplary embodiments and are used to explain this application, but do not constitute an undue limitation of this application. In the drawings:

[0022] Figure 1 This is an exploded schematic diagram of the voice coil motor of this utility model.

[0023] Figure 2 This is an isometric view of one embodiment of the voice coil motor of this utility model.

[0024] Figure 3 This is a schematic diagram of the structure of the spring sheet and carrier of this utility model.

[0025] Figure 4 This is a schematic diagram of the structure of the spring sheet and the base of this utility model.

[0026] Figure 5 This is an isometric view of one embodiment of the voice coil motor of this utility model, with the outer casing structure hidden in the figure.

[0027] Explanation of reference numerals in the attached figures:

[0028] Carrier-1; Impact boss-11; Coil-12; First positioning protrusion-13; Guide hole-14; Base-2; Second positioning protrusion-21; Spring plate-3; First positioning hole-31; Second positioning hole-32; Outer shell-4; Guide block-41; Bar magnet-5. Detailed Implementation

[0029] The present invention will be further described below with reference to the accompanying drawings.

[0030] Please see Figure 1This is an exploded view of the voice coil motor of this utility model. A voice coil motor includes a carrier 1 with a first through hole for placing a lens, and a coil 12 fixed to the side wall of the carrier 1, the coil 12 being fixedly wrapped around the side wall of the carrier 1; a base 2 with a second through hole coaxial with the first through hole; and a spring plate 3 between the carrier 1 and the base 2, the two sides of the spring plate 3 being fixed to the carrier 1 and the base 2 respectively. This design differs from conventional AF voice coil motors by eliminating the upper spring plate located above the carrier 1. Instead, the carrier 1 is supported solely by the lower spring plate (i.e., spring plate 3 in this design), which provides torque balance for the carrier 1. This allows AF focusing to be performed using only one spring plate 3, thereby reducing costs. However, it is important to note that since the original upper spring plate above the carrier 1 has been eliminated, the remaining spring plate 3 must bear the torque that was originally balanced by the upper spring plate. Therefore, the width of spring plate 3 in this design needs to be increased by 65% ​​to 300% based on the original width of the lower spring plate. For example, if the original width is 0.06mm, the increased width would be 0.1mm to 0.24mm.

[0031] Please see Figure 5 This is an isometric view of one embodiment of the voice coil motor of this utility model. In some embodiments, the outer shell 4 is hidden in the figure. The top of the carrier 1 is uniformly provided with a plurality of impact protrusions 11. The number of impact protrusions 1 can be set to eight, and the horizontal cross-section of the impact protrusions 11 can be set to trapezoidal, thereby increasing the impact area of ​​the impact protrusions 11. This makes the force more dispersed when the carrier 1 impacts upward, resulting in better product reliability and impact resistance, reducing defects caused by impacting foreign objects, and improving the overall yield. It is worth mentioning that the cooperation between the aforementioned impact protrusions 11 and the spring sheet 3 can also reduce the risk of tilting of the carrier 1 during movement.

[0032] Please see Figure 2 This is an isometric view of one embodiment of the voice coil motor of this utility model. In some embodiments, the voice coil motor further includes a housing 4, on which a third through hole is provided. The third through hole is coaxial with the first through hole and the second through hole. The housing 4 can be sleeved and fixed on the base 2, and the carrier 1 is wrapped inside it. In order to ensure the stability of the connection between the housing 4 and the base 2, the two can be fixed together by a snap-fit ​​or a pin.

[0033] In some embodiments, a bar magnet 5 is fixed on each of the two opposite sides of the top surface of the base 2, and the position of the bar magnet 5 corresponds to that of the coil 12, so that the bar magnet 5 can interact with the magnetic field generated by the energized coil 12, thereby providing Z-axis drive for the voice coil motor and thus realizing AF focusing.

[0034] In addition, this embodiment also extends at least two guide blocks 41 from the inner side of the third through hole of the outer shell 4 toward the carrier 1. A guide hole 14 is provided at the position corresponding to the guide block 41 on the top of the carrier 1. The guide block 41 can match and be inserted into the guide hole 14, so that the carrier 1 can move along the guide block 41 when moving along the Z-axis, thereby improving the movement stability of the carrier 1. By matching the guide block 41 and the guide hole 14, the carrier 1 is guided in the Z-axis, thereby working synergistically with the torque balance of the spring plate 3 on the carrier 1 to prevent the carrier 1 from tilting during Z-axis movement. Furthermore, through the cooperation of the guide block 41 and the guide hole 14, the torque compensation caused by the tilt of the carrier 1 by the spring plate 3 in the Z-axis can be reduced, thereby reducing the increase in the width of the spring plate 3. For example, the width can be increased by 35% to 60% from the original width of 0.06 mm to 0.081 mm to 0.096 mm, further reducing costs.

[0035] Unlike the previous embodiment, the bar magnet 5 in this solution can also be disposed on the inner wall of the outer casing 4, that is, a bar magnet 5 is fixed on opposite sides of the inner wall of the outer casing 4, and the position of the bar magnet 5 corresponds to that of the coil 12.

[0036] Please see Figure 3 This is a schematic diagram of the structure of the spring sheet 3 and the carrier 1 of this utility model. Figure 4 This is a schematic diagram of the structure of the spring sheet 3 and the base 2 of this utility model. In some embodiments, in order to improve the stability between the spring sheet 3 and the carrier 1, the spring sheet 3 is coaxial with the first through hole and the second through hole, thereby reducing the risk of lens tilting and loss of control. In this embodiment, the spring sheet 3 is electrically connected to the coil 12, thereby providing a current path for the coil 12. In addition, in order to further improve the stability of the spring sheet 3 when achieving torque balance, the bottom of the carrier 1 is provided with a plurality of first positioning protrusions 13, and the top surface of the base 2 is provided with second positioning protrusions 21 at opposite corners. The spring sheet 3 is provided with a first positioning hole 31 and a second positioning hole 32 at positions corresponding to the first positioning protrusions 13 and the second positioning protrusions 21, respectively. The spring sheet 3 is connected to the carrier 1 through the cooperation of the first positioning hole 31 and the first positioning protrusion 13, and the spring sheet 3 is connected to the base 2 through the cooperation of the second positioning hole 32 and the second positioning protrusion 21.

[0037] This solution balances torque by eliminating the upper spring and adjusting the wire width of the lower spring (spring sheet 3 in this solution). It perfectly achieves the use of a single spring sheet 3 to support the carrier 1, balances torque, and generates a pulling force opposite to the magnetic force. This allows the AF focusing stroke requirement to be met with a single spring sheet 3, thus reducing costs. In addition, the design of the two side bar magnets 5 has a relatively simple structure and a regular magnetic field distribution, which can provide a stable driving force. It is suitable for ordinary camera motors with less stringent precision requirements, reducing the number of magnets and lowering motor material costs. The design of the impact protrusion 11 on the carrier 1 has sufficient reserved space and a larger impact area, making the force more dispersed when the carrier 1 impacts upward. This results in better product reliability and resistance to impacts, reduces defects caused by impacts with foreign objects, and improves the overall yield.

[0038] The above description merely illustrates preferred embodiments of the present invention and is quite specific and detailed; however, it should not be construed as limiting the scope of the utility model patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this utility model patent should be determined by the appended claims.

Claims

1. A voice coil motor, characterized in that, include: A carrier having a first through hole for placing a lens, and a coil fixed to the side wall of the carrier; The base has a second through hole that is coaxial with the first through hole; A spring sheet is provided between the carrier and the base, and the two sides of the spring sheet are fixed to the carrier and the base respectively.

2. The voice coil motor as described in claim 1, characterized in that, The top of the carrier is uniformly provided with several impact protrusions.

3. The voice coil motor as described in claim 2, characterized in that, The number of impact protrusions is eight, and the horizontal cross-section of each impact protrusion is trapezoidal.

4. The voice coil motor as described in claim 1, characterized in that, It also includes a housing, on which a third through hole is provided, the third through hole being coaxial with the first through hole and the second through hole; the housing can be fitted and fixed on the base and enclose the carrier inside it.

5. The voice coil motor as described in claim 4, characterized in that, A bar magnet is fixed on each opposite side of the inner wall of the outer casing, and the position of the bar magnet corresponds to that of the coil.

6. The voice coil motor as described in claim 4, characterized in that, At least two guide blocks extend from the inner side of the third through hole toward the carrier. A guide hole is provided on the top of the carrier at a position corresponding to the guide block. The guide block can match the guide hole and be inserted into the guide hole.

7. The voice coil motor as described in claim 1, characterized in that, A bar magnet is fixed to each of the two opposite sides of the top surface of the base, and the position of the bar magnet corresponds to that of the coil.

8. The voice coil motor as described in claim 1, characterized in that, The spring sheet is coaxial with the first through hole and the second through hole; the width of the spring sheet is 0.1mm~0.24mm.

9. The voice coil motor as described in claim 1, characterized in that, The spring sheet is electrically connected to the coil.

10. The voice coil motor as claimed in claim 1, characterized in that, The bottom of the carrier is provided with a plurality of first positioning protrusions, and the top surface of the base is provided with second positioning protrusions at opposite corners. The spring sheet is provided with a first positioning hole and a second positioning hole at positions corresponding to the first positioning protrusions and the second positioning protrusions, respectively. The spring sheet is connected to the carrier through the cooperation of the first positioning hole and the first positioning protrusion, and the spring sheet is connected to the base through the cooperation of the second positioning hole and the second positioning protrusion. The width of the spring sheet is 0.081mm~0.096mm.

Images