CN103176260B - Driving means - Google Patents

Abstract

A driving device, used to drive the movement of the lens module, the driving device includes: a fixed frame, with a storage space and an opening; a movable part, arranged in the storage space, and has a through hole; a magnet, fixed on the fixed frame Upper; a magnet magnetic sheet, fixed on the movable part, the force between the magnet and the magnetic sheet fixes the movable part at a preset position in the fixed frame; a carrier, matched with the fixed frame for receiving a movable part; a guide rod, which is installed in the through hole of the movable part, and its two ends are respectively fixed on the fixed frame and the bearing body; a contact rod, which is fixed on the movable part; and a piezoelectric unit, which is fixed In the opening and against the contact rod, the piezoelectric unit is used for deformation to generate frictional force with the contact rod to drive the movable part to move along the guide rod in the accommodation space.

Description

drive unit

technical field

The invention relates to a driving device, in particular to a driving device using a piezoelectric unit.

Background technique

A digital camera or a mobile phone with a shooting function is equipped with at least one lens module, and the function of the lens module is to drive the optical lens or the optical lens group to move along the optical axis to achieve auto-focus and/or zoom functions.

One of the moving methods of the optical lens group is a piezoelectric motor, which has a piezoelectric unit and a contact rod in contact with the piezoelectric unit. , the movable part can be fixed without moving, so as to prevent the damage of the lens module), and the two magnets are used to attract the contact rod fixed on the movable part to realize that the magnet is located at the two ends of the optical axis path of the optical lens group At the end, the piezoelectric unit is located between the two magnets, the piezoelectric unit is deformed, and the friction between the piezoelectric component and the contact rod drives the movable part to move up and down to realize the focusing or zooming function.

The structure in which the magnets are arranged at both ends of the optical axis path of the optical lens group (that is, the up and down attraction method) will inevitably increase the height of the driving device; in addition, since there must be an acting force between the contact rod and the magnet, the contact rod must be selected to be compatible with the magnet. Materials to which the magnets attract each other, such as metal or magnetic materials, limit the choice of materials for the contact rod.

Contents of the invention

In view of this, it is necessary to provide a driving device with a smaller height.

A driving device for driving a lens module to move. The lens module has an optical axis. The driving device includes: a fixed frame with a storage space where the central axis coincides with the optical axis. The fixed frame has an opening and a first groove; a movable part, which is arranged in the accommodating space, and the movable part has a through hole whose central axis is parallel to the optical axis and a second groove corresponding to the first groove; a magnetic A piece is fixed on the movable part, and the magnetic piece is accommodated in the second groove of the movable part; a magnet is fixed on the fixed frame, and the magnet is accommodated in the second groove of the fixed frame. In the first groove, the active force between the magnet and the magnetic sheet fixes the movable part at a preset position in the fixed frame; a carrier is matched with the fixed frame for accommodating the movable part; a guide rod, which is installed in the through hole of the movable part, and its two ends are respectively fixed on the fixed frame and the carrier; a contact rod, fixed on the movable part and a piezoelectric unit fixed in the opening and against the contact rod, the piezoelectric unit is used to deform to generate friction with the contact rod to drive the movable member along the The guide rod moves in the accommodation space.

Compared with the prior art, the driving device of the embodiment of the present invention enables the movable member to have an initial state by means of the magnets and magnetic sheets arranged on the movable member and the fixed frame, and the magnets and magnetic sheets are arranged away from the piezoelectric unit, Therefore, there is no need to reserve additional height space for accommodating the piezoelectric unit, so that the height of the driving device is reduced; since the magnetic sheet with a small mass is fixed on the movable part, and the magnet with a large mass is located on the fixed frame, the piezoelectric unit The electric unit needs a small driving force to drive the movement of the lens module; in addition, because only one magnet is used, the assembly process of the drive device can be simplified, and the alignment problem of the two magnets can also be avoided; The attractive force fixes the movable part, and there is no interaction between the magnet and the contact rod, so the material selection of the contact rod is not limited and can be any material.

Description of drawings

Fig. 1 is a schematic diagram of a driving device according to an embodiment of the present invention.

Fig. 2 is an exploded view of the driving device of the embodiment of the present invention.

Fig. 3 is an exploded view from another angle of the driving device of the embodiment of the present invention.

Description of main component symbols

drive unit 100

Fixtures 11

First Containment Space 110

First through hole 111

opening 112

First positioning hole 113

First groove 114

Moving parts 12

Second Containment Space 120

Second through hole 121

The third through hole 122

Second groove 123

Third groove 124

carrier 13

Clear hole 130

Blind hole 131

Positioning post 132

guide rod 14

Piezoelectric unit 15

magnet 16

Magnetic sheet 17

circuit board 18

Holder 19

contact rod 20

The following specific embodiments will further illustrate the present invention in conjunction with the above-mentioned drawings.

detailed description

Please refer to Fig. 1, Fig. 2 and Fig. 3, the driving device 100 provided by the embodiment of the present invention is used to drive the movement of the lens module (not shown) to realize the focusing operation, and the driving device 100 includes a fixed frame 11, a movable part 12. Carrier 13 , guide rod 14 , piezoelectric unit 15 , magnet 16 , magnetic sheet 17 , circuit board 18 , holder 19 and contact rod 20 .

The circuit board 18 is used to provide electrical energy to the piezoelectric unit 15 to make it work. When the circuit board 18 provides voltage to the piezoelectric unit 15, the piezoelectric unit 15 has mechanical deformation, and voltages in different directions have mechanical deformations in different directions, and different Different magnitudes of voltage have different magnitudes of mechanical deformation. The circuit board 18 may be a general printed circuit board or a flexible circuit board (FPCB).

The fixing frame 11 has a square structure with a first receiving space 110 for receiving the movable element 12 , and the central axis of the first receiving space 110 coincides with the optical axis of the lens module. One corner of the fixed frame 11 has a first through hole 111 whose central axis is parallel to the optical axis of the lens module. The side wall of the fixed frame 11 with the first through hole 111 has an opening 112 for accommodating the piezoelectric unit 15. The holder 19 is used to fix the piezoelectric unit 15 in the opening 112 and fix the circuit board 18 on the fixing frame 11 . The end of the fixed frame 11 near the carrier 13 has a first positioning hole 113, and the side wall of the fixed frame 11 with the opening 112 has a first groove 114, the first groove 114 is used to accommodate the fixed magnet 16, and the magnet 16 can be used Glue is fixed in the first groove 114 .

The movable part 12 is movably arranged in the first storage space 110. The movable part 12 is a square structure with a second storage space 120 whose central axis coincides with the optical axis of the lens module. The second storage space 120 is used to accommodate The lens module, so that the lens module moves up and down along the optical axis driven by the movable member 12 to achieve focusing or zooming operations.

Corresponding to the first through hole 111 on the fixed frame 11, there is a second through hole 121 and a third through hole 122 parallel to the optical axis of the lens module on one corner of the movable member 12 and the second through hole 121 and the third through hole 122 is set coaxially, the guide rod 14 is set in the second through hole 121 and the third through hole 122, and the two ends are respectively located in the first through hole 111 and the blind hole 131, and are located in the first through hole 111 and the blind hole 131 (the carrier 13 has a corresponding first through hole 111, the second through hole 121 and the third through hole 122, and the part in it can be fixed on the fixed frame 11 and the carrier 13 by dispensing, so that the movable The component 12 moves up and down in the first receiving space 110 under the guidance of the guide rod 14 .

Corresponding to the first groove 114 on the fixed frame 11, the movable part 12 has a second groove 123, the second groove 123 is used to accommodate the magnetic sheet 17, the magnetic sheet 17 and the magnet 16 attract each other, so that the movable part 12 is fixed at a certain position relative to the fixed frame 11, so that the lens module has an initial state.

The movable member 12 also has a strip-shaped third groove 124 whose length is parallel to the optical axis of the lens module on the side wall with the second groove 123. The third groove 124 is used to accommodate the fixed contact rod 20. When the piezoelectric The unit 15 is fixed in the opening 112 of the fixing frame 11 , and the piezoelectric unit 15 is in contact with the contact rod 20 .

Relative to the shape of the fixed frame 11 and the movable part 12, the carrier 13 is a square structure, and its geometric center has a light hole 130, which is used to allow the light passing through the lens module to enter the image sensor arranged on the carrier 13 (Fig. not shown) for imaging. The four corners of the carrier 13 respectively have a first positioning column 132 , and the first positioning column 132 cooperates with the first positioning hole 113 on the fixing frame 11 so that the fixing frame 11 is fixed on the carrier 13 .

When the circuit board 18 supplies voltage to the piezoelectric unit 15, the piezoelectric unit 15 can convert the input electric energy into its own mechanical deformation, and the mechanical deformation has a component parallel to the optical axis of the lens module, and the deformation component makes the piezoelectric unit 15 There is a relative displacement between the piezoelectric unit 15 and the contact rod 20. When the interaction force between the piezoelectric unit 15 and the contact rod 20 is greater than the friction force between the two, the piezoelectric unit 15 is fixed on the fixed frame 11 and cannot move , so the contact rod 20 drives the movable part 12 under the active force to move up and down along the guide rod 14 in the first accommodation space 110 of the fixed frame 11 under the drive of the deformation component of the piezoelectric unit 15, so that the lens module Driven by the movable member 12, a focusing or zooming operation is implemented to obtain a clear image.

The magnet 16 and the magnetic sheet 17 of the driving device 100 are arranged away from the piezoelectric unit 15, so there is no need to reserve an additional height space for accommodating the piezoelectric unit 15, thereby making the height of the driving device 100 smaller; 17 is fixed on the movable part 12, and the magnet 16 with larger mass is located on the fixed frame 11, so that the piezoelectric unit 15 can drive the lens module to move with a relatively small driving force; in addition, because only one magnet 16 can be used to simplify The assembly process of the driving device 100 can also avoid the alignment problem of the two magnets; moreover, the movable part 12 is fixed by the attractive force between the magnet 16 and the magnetic sheet 17, and there is no interaction between the magnet 16 and the contact rod 20 , Therefore, the material selection of the contact rod 20 is not limited, and can be any material.

It can be understood that those skilled in the art can also make other changes within the spirit of the present invention to be used in the design of the present invention, as long as they do not deviate from the technical effects of the present invention. These changes made according to the spirit of the present invention should be included in the scope of the present invention.

Claims (7)

1. a driving means, is used for driving the motion of camera lens module to realize focusing or zoom, described camera lens mould Group has optical axis, and described driving means includes:

One fixed mount, has the receiving space of central shaft and optical axis coincidence, described fixed mount has opening With the first groove；

One movable piece, is arranged in described receiving space, and described movable piece has the parallel described light of central shaft The through hole of axle and second groove corresponding with the first groove；

One magnetic piece, is fixed on described movable piece, and described magnetic piece is contained in the of described movable piece In two grooves；

One Magnet, on fixing described fixed mount, it is first recessed that described Magnet is contained on described fixed mount In groove, described movable piece is fixed in described fixed mount by the active force between described Magnet and magnetic piece On one predeterminated position；

One supporting body, matches for housing described movable piece with described fixed mount；

One guide rod, is located in the through hole of described movable piece, and two ends be separately fixed at described fixed mount and On supporting body；

One contact bar, is fixed on described movable piece；And

One piezoelectric unit, in being fixed on described opening and against described contact bar, described piezoelectric unit is used for Deform upon and drive described movable piece to exist along described guide rod to contact generation frictional force between bar with described Motion in described receiving space.

2. driving means as claimed in claim 1, it is characterised in that on described fixed mount, there is through hole, One end of described guide rod is fixed in described through hole.

3. driving means as claimed in claim 2, it is characterised in that on described supporting body, there is blind hole, The other end of described guide rod is fixed in described blind hole.

4. driving means as claimed in claim 1, it is characterised in that have described on described movable piece Having the 3rd groove of the parallel described optical axis of length direction on the sidewall of the second groove, described contact bar is fixed In described 3rd groove.

5. the driving means as described in any one of Claims 1-4, it is characterised in that described driving means Farther including retaining piece, described retaining piece is used for being fixed in described opening described piezoelectric unit.

6. driving means as claimed in claim 5, it is characterised in that described driving means is wrapped further Including a circuit board, described circuit board is fixed on described retaining piece and is electrical connected with described piezoelectric unit.

7. driving means as claimed in claim 5, it is characterised in that described fixed mount and described carrying The end face that body is relative is respectively provided with hole, location and locating dowel, and hole, described location and locating dowel match so that institute State fixed mount to be fixed on described supporting body.