TWI424254B - Lens driving apparatus - Google Patents

Description

Lens drive

The invention relates to the field of camera technology, and in particular to a lens driving device.

With the development of science and technology, the lens drive has been applied to autofocus systems such as digital cameras, cell phone cameras or digital cameras. When the lens is in the startup phase, the current is generated in the coil, regardless of the current, the driving force is generated to make the lens move immediately. In addition, during the lens focusing process, the lens needs to be reset to zero, and the lens needs to be applied to the lens. The pulling force of the driving force is reversed. Therefore, the lens drive device needs to provide a pre-tensioning module.

The technical problem to be solved by the present invention is to provide a lens driving device capable of generating a preload force between the lens frame and the base.

In order to solve the above technical problem, the present invention provides a lens driving device including a moving portion and a fixed portion, the moving portion is located in the fixed portion, the moving portion includes a lens frame and a coil, the fixed portion includes a base, the lens frame is located on the base, and the coil Fixed on the lens frame, the fixed part further comprises a magnetic group, and the magnetic group is arranged radially along the lens frame. When the coil is energized, a force for driving the lens frame is generated between the coil and the magnetic group, and the lens frame and the base are on one of the components. A magnetizer is fixed, and a magnet is fixed on the other component. The magnetic force generated by the mutual attraction between the magnetizer and the magnet can pull the lens frame to return the lens to the initial position.

Since the magnetizer is fixed to one of the lens frame and the base, and the magnet is fixed to the other component, the magnetic force generated by the mutual attraction between the magnet and the magnet causes a preload between the base and the lens frame. Therefore, the lens fixed on the lens frame is in the starting phase, and when the current reaches a certain magnitude, the electromagnetic driving force in the coil can be moved when the electromagnetic driving force is greater than the pre-tightening force; When the focus is zero, when the electromagnetic driving force in the coil is less than the pre-tightening force, the pre-tightening force can pull the lens to return the lens to the initial position.

The present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It is understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

1 , 2 and 3, a lens driving device 1 according to an embodiment of the present invention includes a moving portion 21 and a fixed portion 22, the moving portion 21 is located in the fixed portion 22, and the moving portion 21 includes a lens frame 211 and a fixed portion. 22 includes a base 223 on which the lens mount 211 is located. One of the lens mount 211 and the base 223 has a magnetizer 11 fixed thereto, and the other assembly has a magnet 12 fixed thereto.

The lead magnet 11 may be an iron block or an iron ball, the magnet 12 may be a magnetic column, and at least two pairs of iron blocks or iron balls and magnetic columns are evenly arranged on the lens frame 211 and the base 223. As a preferred embodiment of the present invention, the bottom of the lens frame 211 is symmetrically disposed with two grooves 111, which are iron balls that are fixed in the grooves 111. The position of the base 223 opposite to the groove 111 on the lens frame 211 is also symmetrically disposed with two through holes 121. The magnet 12 is a magnetic column and is fixed in the through hole 121.

The base 223 and the lens frame 211 respectively fix the magnetizer 11 and the magnet 12, and the magnetic force generated by the attraction between the magnetizer 11 and the magnet 12 causes a pre-tightening force between the base 223 and the lens frame 211, thereby achieving fixation. The lens 213 on the lens frame 211 can be moved when the current reaches a certain level, and the electromagnetic driving force in the coil is greater than the pre-tightening force; and the lens 213 is adjusted to return to the zero phase, when the electromagnetic drive in the coil When the force is less than the pre-tightening force, the pre-tightening force can pull the lens to return the lens 213 to the initial position.

The magnetizer 11 and the magnet 12 may also be in a ring shape or other shape, and the number of the magnetizer 11 and the magnet 12 may be fixed to one of the lens frame 211 and the base 223, respectively. It is within the scope of the present invention to enable a pre-tightening force between the magnetizer 11 and the magnet 12.

As shown in FIGS. 1 and 3, the moving portion 21 further includes a coil 212 and a hoop 214, and the coil 212 is fixed to the lens frame 211. The fixing portion 22 includes a magnetic group 221 and an iron shell 222. The iron shell 222 includes an outer ring 2221 and a yoke 2222 extending inwardly from the top end of the outer ring. The yoke portion 2222 is provided with a through hole corresponding to the lens frame 211. The magnetic group 221 is fixed on the inner side of the outer ring of the iron shell 222, the iron ring 214 abuts against the lens frame 211, and there is a gap between the yoke portion of the iron shell 222, and the iron ring 214 and the iron shell 222 together constitute an excitation component.

When the moving portion 21 moves relative to the fixed portion 22, in order to reduce friction, a gap is left between the iron shell 222 and the iron ring 214, between the magnet 221 and the coil 212, and the iron ring 214 is tightly attached to the lens frame 211 without gap. Therefore, the reduced gap between the iron ring 214 and the lens frame 211 can reduce the volume of the lens driving device 2.

The coil 212 can be fixedly connected to the iron ring 214 in addition to the lens frame 211. Thus, the iron ring 214 is located between the lens frame 211 and the coil 212, further eliminating the gap between the coil 212 and the iron ring 214, so that the lens The volume of the drive device 1 can be further reduced.

As shown in FIG. 4, the lens driving device 1 further includes an upper spring piece 232 and a lower spring piece 233. The inner rings of the upper spring piece 232 and the lower spring piece 233 are respectively connected to the two ends of the coil 212, and the upper spring piece 232 and the lower side are respectively connected. The outer ring of the spring piece 233 has a contact piece 234, and the upper spring piece 232 and the lower spring piece 233 are connected to the base 223 through the contact piece 234. When the upper spring piece 232 and the lower spring piece 233 are energized, current is introduced into the inner ring through the outer ring of the two spring pieces, thereby energizing the coil 212 to function as a wire. In addition, when the coil 212 is energized to drive the lens frame 211 to move, the two spring pieces 232, 233 are deformed to generate an elastic force, and when the electromagnetic force in the coil 212 and the elastic force generated by the two spring pieces 232, 233 are balanced, the moving portion 21 will stop. Therefore, the device can control the displacement of the moving portion 21 by controlling the magnitude of the current.

The number of the magnetic group 211 may be several or the magnetic group 211 may be annular, and the iron shell 222 may have a circular, rectangular or other shape in the circumferential direction, and the circular hole at the top of the iron shell 222 may also be square or other. It can accommodate the shape of the iron ring 214.

The above is only the preferred embodiment of the present invention, and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection of the present invention. Within the scope.

1‧‧‧Lens driver

11‧‧‧Bolt magnet

12‧‧‧ magnet

21‧‧‧ sports section

22‧‧‧Fixed part

111‧‧‧ Groove

121‧‧‧through hole

211‧‧‧Lens frame

212‧‧‧ coil

213‧‧‧ lens

214‧‧‧iron ring

221‧‧‧ Magnetic Group

222‧‧‧ iron shell

223‧‧‧Base

232‧‧‧Upper spring

233‧‧‧ Lower spring piece

234‧‧‧Contacts

2222‧‧‧ yoke

2221‧‧‧Outer ring

A-A‧‧‧ cross-sectional line

The above and other features and advantages of the present invention will become more apparent to those skilled in the art in the <RTIgt; Schematic diagram of structural decomposition.

2 is a schematic top plan view of a lens driving device according to an embodiment of the invention.

FIG. 3 is a cross-sectional view of the lens driving device according to the embodiment of the present invention taken along line A-A of FIG. 2.

4 is a perspective view showing a moving part of a lens driving device according to an embodiment of the present invention.

11‧‧‧Bolt magnet

12‧‧‧ magnet

21‧‧‧ sports section

22‧‧‧Fixed part

111‧‧‧ Groove

211‧‧‧Lens frame

212‧‧‧ coil

213‧‧‧ lens

214‧‧‧iron ring

222‧‧‧ iron shell

223‧‧‧Base

232‧‧‧Upper spring

233‧‧‧ Lower spring piece

Claims (9)

A lens driving device comprising: a fixing portion including a base; and a moving portion located in the fixed portion and including a lens frame and a coil, the lens frame being located on the base, the coil being fixed to the lens frame Wherein: the fixed portion further includes a magnetic group, the magnetic group is disposed radially along the lens frame, and when the coil is energized, a movement between the coil and the magnetic group is generated to drive the lens frame a force, a magnetizer is fixed on one of the lens frame and the base, and a magnet is fixed on the other component, and a magnetic force generated by mutual attraction between the magnet and the magnet can pull the lens frame to thereby The lens returns to its original position. The lens driving device of claim 1, wherein: the plurality of magnetizers and magnets are respectively disposed on the lens frame and the base uniformly along the circumferential direction of the lens. The lens driving device of claim 1 or 2, wherein: the bottom of the lens frame is provided with a groove, and the magnetizer is fixed in the groove, and the base corresponds to the bottom of the lens frame. The position of the groove is provided with a through hole, and the magnet is fixed in the through hole. The lens driving device of claim 1 or 2, wherein the magnetizer is an iron block or an iron ball. The lens driving device of claim 1 or 2, wherein the magnet is a magnetic column. The lens driving device of claim 1, wherein: the magnetizer is a ring-shaped magnet, and the magnet is a ring magnet. The lens driving device of claim 1, wherein: the moving portion further comprises an iron ring; the fixing portion comprises an iron shell, the iron shell comprising an outer ring and a yoke extending inwardly from the top end of the outer ring a through hole corresponding to the lens frame, the magnetic group is fixed on the iron shell On the inner side of the outer ring, the iron ring abuts against the lens frame, and there is a gap with the yoke of the iron shell, and the iron shell and the iron ring together constitute an excitation component. The lens driving device of claim 7, wherein the coil is further connected to the iron ring, and the iron ring is located between the coil and the lens frame. The lens driving device of claim 7 or 8, wherein: the lens driving device further comprises an upper spring piece and a lower spring piece, wherein the inner ring of the upper spring piece and the lower spring piece respectively are opposite to the coil The end lead is connected, and the outer ring of the upper spring piece and the lower spring piece have contact pieces, and the upper spring piece and the lower spring piece are connected to the base through the contact piece.