Piezoelectric driving device

Abstract

The utility model belongs to the technical field of optical components, and particularly relates to a piezoelectric driving device, which comprises a shell, a base, a piezoelectric mechanism and a carrier, a hollow cavity is arranged between the shell and the base, and the piezoelectric mechanism and the carrier are arranged in the hollow cavity; the piezoelectric mechanism comprises a friction rod and an elastic piece, the friction rod is arranged on the base and located on the outer side of the middle of one side of the carrier, and the elastic piece is arranged on the carrier and makes contact with the friction rod. The shell is provided with a guide hole, and the upper end of the friction rod penetrates into the guide hole. Under the action of friction force and the guide action of the guide hole, the friction bar can drive the carrier to move stably and longitudinally, and shaking of the carrier in the longitudinal movement process is avoided.

Description

Technical Field

[0001] The utility model belongs to the technical field of optical components, and particularly relates to a piezoelectric driving device. Background Art

[0002] With the development of technology, many current electronic devices (such as smart phones or digital cameras) have the functions of taking pictures or videos. The use of these electronic devices is becoming more and more common, and they are developing towards the design directions of convenience, thinness and lightness to provide users with more choices.

[0003] Some electronic devices with the functions of taking pictures or videos are provided with lens driving devices to drive the movement of optical components such as lenses, so as to achieve the autofocus function. Light can pass through the optical components to form an image on the photosensitive component.

[0004] In order to achieve the autofocus function, the Smooth Impact Drive Mechanism (SIDM) has emerged. SIDM is a driving mechanism that uses piezoelectric elements. One end of the solid fixing part of the piezoelectric element is attached to the other end of the driving friction part, and the driving friction force is maintained on the moving body to the component. The characteristics of SIDM are compact, high-precision and silent driving, while the challenges faced by SIDM include low efficiency, durability and the need for a rear sensor for feeding.

[0005] With the popularization of terminals such as smart phones, how to make the lens driving device achieve a stable autofocus function is what those skilled in the art need to actively consider. Summary of the Utility Model

[0006] Aiming at the above technical problems, the utility model aims to provide a piezoelectric driving device.

[0007] A piezoelectric driving device includes a housing, a base, a piezoelectric mechanism and a carrier. There is a hollow cavity between the housing and the base, and the piezoelectric mechanism and the carrier are arranged in the hollow cavity;

[0008] The piezoelectric mechanism includes a friction rod and a spring piece. The friction rod is arranged on the base and located outside the middle of one side of the carrier, and the spring piece is arranged on the carrier and contacts the friction rod;

[0009] A guiding hole is arranged on the housing, and the upper end of the friction rod penetrates into the guiding hole.

[0010] Optionally, the piezoelectric mechanism further includes a piezoelectric circuit, a weight block and a piezoelectric block. The weight block is arranged on the base, the piezoelectric block is arranged on the upper end of the weight block and connected to the piezoelectric circuit, and the friction rod is arranged on the upper end of the piezoelectric block.

[0011] Optionally, an installation opening is provided at the bottom inside the base, the counterweight and the piezoelectric block are arranged in the installation opening, and one end of the wire pressing circuit passes through the installation opening and is connected to the piezoelectric block;

[0012] An installation groove is longitudinally arranged inside the base, the bottom of the installation groove communicates with the installation opening, the friction rod is arranged in the installation groove, the lower end of the friction rod passes through the bottom of the installation groove and is arranged on the piezoelectric block in the installation opening, and the upper end of the friction rod extends out of the upper end of the installation groove.

[0013] Optionally, an elastic avoidance groove is provided on one side of the carrier, and the elastic sheet is arranged outside the elastic avoidance groove.

[0014] Optionally, a ball groove is provided between the carrier and the inner wall of the base, and balls are arranged in the ball groove.

[0015] Optionally, magnet grooves are provided on both sides of the elastic avoidance groove, and magnetic attraction magnets are arranged in the magnet grooves;

[0016] A magnetic attraction iron sheet is arranged outside the base, and both sides of the magnetic attraction iron sheet are located outside the two magnetic attraction magnets.

[0017] Optionally, a circuit board is arranged outside the base, a control IC circuit is arranged on one side of the circuit board, and the bottom end of the control IC circuit is communicated with an external circuit.

[0018] Optionally, the circuit board is an FPC board.

[0019] Optionally, an induction capacitor is arranged inside the circuit board, an induction magnet is arranged on one side edge of the carrier, and the induction magnet and the induction capacitor are arranged opposite to each other inside and outside.

[0020] Optionally, an avoidance notch communicating inside and outside is provided on the base, and the avoidance notch is located between the induction magnet and the induction capacitor.

[0021] Optionally, the end of the circuit board is connected to the piezoelectric circuit.

[0022] Optionally, a welding notch communicating inside and outside is provided on the outer shell, and the welding notch is located outside the end of the circuit board.

[0023] Beneficial effects: The present utility model has at least one or more of the following advantages: The elastic piece of the present utility model presses the carrier against the inner wall of the base under the action of elastic force. Since the piezoelectric mechanism is arranged at the middle position of one side edge of the carrier, when being pressed, the two sides of the opposite side wall of the carrier can be better abutted against the inner wall of the base. Under the action of frictional force and with the guiding effect of the guiding hole, the friction rod can drive the carrier to perform stable longitudinal movement, avoiding shaking during the longitudinal movement of the carrier. Description of the Drawings

[0024] Figure 1 is a schematic structural diagram of the present utility model;

[0025] Figure 2 is Figure 1 the A-A cross-sectional view of

[0026] Figure 3 is Figure 1 the exploded view of

[0027] Figure 4 is Figure 3 the further exploded view of

[0028] Figure 5 is the positional relationship diagram between the base and the carrier of the present utility model;

[0029] Figure 6 is Figure 5 the exploded view of

[0030] Figure 7 is the schematic structural diagram of the base part of the present utility model;

[0031] Figure 8 is Figure 7 the exploded view of

[0032] Figure 9 is the exploded structural diagram of the carrier part of the present utility model. Detailed Embodiments

[0033] The following will describe in detail the preferred embodiments of the present utility model with reference to the drawings, so as to more clearly understand the purpose, features and advantages of the present utility model. It should be understood that the embodiments shown in the drawings are not limitations on the scope of the present utility model, but only to illustrate the essential spirit of the technical solution of the present utility model.

[0034] In the following description, for the purpose of explaining various disclosed embodiments, certain specific details are set forth to provide a thorough understanding of the various disclosed embodiments. However, those skilled in the relevant art will recognize that the embodiments can be practiced without one or more of these specific details. In other instances, well-known devices, structures, and techniques associated with the present application may not be shown or described in detail so as to avoid unnecessarily obscuring the description of the embodiments.

[0035] References throughout this specification to "one embodiment" or "an embodiment" mean that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment. Thus, the appearances of "in one embodiment" or "in an embodiment" in various places throughout this specification are not necessarily all referring to the same embodiment. Additionally, the particular features, structures, or characteristics may be combined in any manner in one or more embodiments.

[0036] In the following description, in order to clearly show the structure and working mode of the present utility model, many directional terms will be used for description. However, words such as "front", "rear", "left", "right", "outer", "inner", "outward", "inward", "up", "down", etc. should be understood as convenient terms and should not be construed as limiting terms.

[0037] Refer to Figures 1 to 5 , an embodiment of the present utility model provides a piezoelectric driving device. The piezoelectric driving device includes a housing 1, a base 2, a piezoelectric mechanism 3, and a carrier 4. There is a hollow cavity between the housing 1 and the base 2. The housing 1 and the base 2 are preferably connected by buckling to form the hollow cavity. The piezoelectric mechanism 3 and the carrier 4 are disposed in the hollow cavity. A longitudinally (i.e., in the up and down direction) communicating lens through-hole is provided in the middle of the housing 1, the base 2, the piezoelectric mechanism 3, and the carrier 4 to accommodate a lens. A lens is installed in the carrier 4. Under the action of the piezoelectric mechanism 3, the carrier 4 and the lens move longitudinally relative to the base 2 to achieve the zoom effect of the lens.

[0038] Refer to Figures 6 to 9 , the piezoelectric mechanism 3 includes a friction rod 31 and a spring piece 32. The friction rod 31 is disposed on the base 2 and outside the middle of one side of the carrier 4, and the spring piece 32 is disposed on the middle of one side of the carrier 4 and contacts the friction rod 31.

[0039] Refer to Figure 1 , Figure 2 and Figure 3 , a guiding hole 11 is provided on the housing 1, and the upper end of the friction rod 31 penetrates into the guiding hole 11. As shown in Figure 2 , when the piezoelectric mechanism 3 does not drive the carrier 4 to move longitudinally, the upper end of the friction rod 31 preferably does not protrude from the guiding hole 11, and more preferably, the upper end of the friction rod 31 is flush with the guiding hole 11.

[0040] The shrapnel 32 of the present utility model squeezes the carrier 4 against the inner wall of the base 2 under the action of elastic force. Since the piezoelectric mechanism 3 is arranged in the middle position of one side of the carrier 4, when squeezing, both sides of the opposite side wall of the carrier 4 can better abut against the inner wall of the base 2. Under the action of friction force, the friction rod 31 can drive the shrapnel 32 and the carrier 3 to move stably longitudinally under the guiding action of the guiding hole 11, avoiding shaking during the longitudinal movement of the carrier 3.

[0041] In one embodiment, referring to Figures 6 to 8 , the piezoelectric mechanism 3 further includes a piezoelectric circuit 33, a counterweight 34 and a piezoelectric block 35. The counterweight 34 is arranged on the base 2, the piezoelectric block 35 is arranged on the upper end of the counterweight 34 and is connected to the piezoelectric circuit 33, and the friction rod 31 is arranged on the upper end of the piezoelectric block 35.

[0042] The piezoelectric circuit 33 supplies power to the piezoelectric block 35. After the piezoelectric block 35 is electrified and deformed, the friction rod 31 drives the shrapnel 32 and the carrier 4 to move longitudinally under the action of friction force.

[0043] In one embodiment, referring to Figures 6 to 8 , an installation opening 21 is arranged at the inner bottom of the base 2. The counterweight 34 and the piezoelectric block 35 are arranged in the installation opening 21, and one end of the wire-pressing circuit passes through the installation opening 21 and is connected to the piezoelectric block 35.

[0044] An installation groove 22 is arranged longitudinally on the inner side of the base 2. The bottom of the installation groove 22 communicates with the installation opening 21. The friction rod 31 is arranged in the installation groove 22. The lower end of the friction rod 31 passes through the bottom of the installation groove 22 and is arranged on the piezoelectric block 35 in the installation opening 21, and the upper end of the friction rod 31 extends out of the upper end of the installation groove 22 and then is inserted into the guiding hole 11.

[0045] In one embodiment, the installation groove 22 is a groove with a V-shaped cross-section structure, and the inner side surface of the installation groove 22 is an open structure.

[0046] In one embodiment, referring to Figure 6 and Figure 9 , an elastic avoidance groove 41 is arranged on one side of the carrier 4, and the shrapnel 32 is arranged outside the elastic avoidance groove 41.

[0047] In one embodiment, referring to Figures 6 to 9 , a ball groove is arranged between the carrier 4 and the inner wall of the base 2. The length direction of the ball groove is longitudinal, and balls 5 are arranged in the ball groove.

[0048] Specifically, a first ball groove 51 is arranged on the outer wall of the carrier 4, a second ball groove 52 is arranged on the inner wall of the base 2, the first ball groove 51 and the second ball groove 52 are arranged opposite to each other inside and outside, and the balls 5 are arranged between the first ball groove 51 and the second ball groove 52.

[0049] In this embodiment, the design of the ball 5 can reduce the frictional force during the longitudinal movement of the carrier 4.

[0050] In one embodiment, both the first ball groove 51 and the second ball groove 52 are grooves with a V-shaped cross-section, wherein the outer side of the first ball groove 51 is an open structure, and the inner side of the second ball groove 52 is an open structure.

[0051] In one embodiment, the ball 5 is installed between the carrier 4 and the base 2 on the same side as the elastic avoidance groove 41.

[0052] Refer to Figure 6 , preferably, ball grooves and balls 5 are respectively arranged on both sides of the elastic avoidance groove 41.

[0053] In one embodiment, the number of balls 5 in the ball groove is one or more. When there are multiple balls 5, the multiple balls 5 are arranged side by side longitudinally in the ball groove.

[0054] In one embodiment, refer to Figure 6 and Figure 9 , a magnet groove 42 is provided on the carrier 4, the magnet groove 42 is located on both sides of the elastic avoidance groove 41, and a magnetic attraction magnet 61 is arranged in the magnet groove 42.

[0055] Refer to Figure 5 and, Figure 6 and Figure 8 , a magnetic attraction iron sheet 62 is arranged on the outer side of the base 2, and both sides of the magnetic attraction iron sheet 62 are located outside the two magnetic attraction magnets 61.

[0056] In this embodiment, an attractive force will be generated between the magnetic attraction iron sheet 62 and the magnetic attraction magnet 61, and this attractive force makes the carrier 4 closely adhere to the inner side direction of the base 2, so that the carrier 4 and the ball 5 are in a contact state, preventing the ball 5 from falling off. At the same time, the bending degree of the elastic piece 32 is increased, making the elastic frictional force between the elastic piece 32 and the friction rod 31 greater, and improving the driving effect of the piezoelectric mechanism 3.

[0057] In one embodiment, refer to Figure 3 and Figure 4 , a circuit board 7 is arranged on the outer side of the base 2, a control IC circuit 71 is arranged on one side of the circuit board 7, and the bottom end of the control IC circuit 71 is connected to the external circuit.

[0058] Specifically, the bottom end of the control IC circuit 71 extends out of the bottom end of the base 2 to facilitate connection with the external circuit for power supply.

[0059] In one embodiment, the circuit board 7 is an FPC board.

[0060] In one embodiment, refer to Figure 4, an induction capacitor 81 is provided inside the circuit board 7, and an induction magnet 82 is provided on one side of the carrier 4. The induction magnet 82 and the induction capacitor 81 are arranged opposite to each other inside and outside to realize the monitoring of the longitudinal position of the carrier 4.

[0061] In one embodiment, referring to Figure 9 , an induction magnet mounting groove 43 is provided on the carrier 4, and the induction magnet 82 is arranged in the induction magnet mounting groove 43.

[0062] In one embodiment, the induction magnet 82 or the induction magnet mounting groove 43 is located on the side of the carrier 4 adjacent to the elastic piece 32.

[0063] In one embodiment, referring to Figure 6 , an avoidance notch 23 communicating inside and outside is provided on the base 2, and the avoidance notch 23 is located between the induction magnet 82 and the induction capacitor 81.

[0064] In one embodiment, the end of the circuit board 7 is connected to the piezoelectric circuit 33 to realize the power supply operation of the piezoelectric mechanism 3.

[0065] In one embodiment, referring to Figure 3 , a welding notch 12 communicating inside and outside is provided on the outer shell 1, and the welding notch 12 is located outside the end of the circuit board 7 to facilitate the welding operation between the circuit board 7 and the piezoelectric circuit 33.

[0066] In one embodiment, the circuit board 7 adopts an inverted L-shaped structure. A control IC circuit 71 is provided on one side of the circuit board 7, and an induction capacitor 81 is provided on the other side of the circuit board.

[0067] The preferred embodiments of the present invention have been described in detail above. However, it should be understood that after reading the above teachings of the present invention, those skilled in the art can make various changes or modifications to the present invention. These equivalent forms also fall within the scope defined by the appended claims of this application.

Claims

1. A piezoelectric drive device, comprising a housing, a base, a piezoelectric mechanism and a carrier, wherein a hollow cavity is provided between the housing and the base, and the piezoelectric mechanism and the carrier are arranged in the hollow cavity; It is characterized in that The piezoelectric mechanism comprises a friction rod and a spring sheet, wherein the friction rod is arranged on the base and located outside the middle of one side of the carrier, and the spring sheet is arranged on the carrier and contacts the friction rod; The shell is provided with a guide hole, and the upper end of the friction rod is inserted into the guide hole.

2. The piezoelectric drive device according to claim 1, wherein: The piezoelectric mechanism also includes a piezoelectric circuit, a counterweight and a piezoelectric block. The counterweight is arranged on the base, the piezoelectric block is arranged on the upper end of the counterweight and connected to the piezoelectric circuit, and the friction rod is arranged on the upper end of the piezoelectric block.

3. The piezoelectric drive device according to claim 2, wherein: The bottom inner side of the base is provided with a mounting opening, the counterweight block and the piezoelectric block are arranged in the mounting opening, and one end of the piezoelectric circuit passes through the mounting opening and is connected to the piezoelectric block; A mounting groove is longitudinally arranged on the inner side of the base, the bottom of the mounting groove is connected to the mounting port, the friction rod is arranged in the mounting groove, the lower end of the friction rod passes through the bottom of the mounting groove and is arranged on the piezoelectric block in the mounting port, and the upper end of the friction rod extends out of the upper end of the mounting groove.

4. The piezoelectric drive device according to claim 1, 2 or 3, characterized in that: An elastic avoidance groove is arranged on one side of the carrier, and the spring sheet is arranged outside the elastic avoidance groove.

5. The piezoelectric drive device according to claim 4, characterized in that: A ball groove is arranged between the carrier and the inner wall of the base, and a ball is arranged in the ball groove.

6. The piezoelectric drive device according to claim 5, characterized in that: Magnetic grooves are arranged on both sides of the elastic avoidance groove, and magnetic magnets are arranged in the magnetic grooves; A magnetic iron sheet is arranged on the outside of the base, and two sides of the magnetic iron sheet are located on the outsides of the two magnetic magnets.

7. The piezoelectric drive device according to claim 2, wherein: A circuit board is arranged on the outside of the base, a control IC circuit is arranged on one side of the circuit board, and the bottom end of the control IC circuit is connected with an external circuit.

8. The piezoelectric drive device according to claim 7, characterized in that: An inductive capacitor is arranged inside the circuit board, and an inductive magnet is arranged on one side of the carrier. The inductive magnet is arranged opposite to the inductive capacitor inside and outside.

9. The piezoelectric drive device according to claim 8, characterized in that: The base is provided with an escape gap which is connected inside and outside, and the escape gap is located between the induction magnet and the induction capacitor.

10. The piezoelectric drive device according to claim 7, wherein: The end of the circuit board is connected to the piezoelectric circuit; The shell is provided with a welding notch communicating with the inside and outside, and the welding notch is located outside the end of the circuit board.

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