TWI411869B - Lens driving apparatus - Google Patents

Abstract

The present invention discloses a lens driving apparatus, comprising a motion part and a fixing part. The motion part is positioned in the fixing part, and having a gap therebetween. The motion part comprises a coil and a lens holder. The coil is fixed on the lens holder. The fixing part comprises magnets and an iron shell. The iron shell comprises an outer-ring and a yoke part. The yoke part extends from a top end of the outer-ring and bends inwards. The yoke part has a through hole corresponding to the lens holder. The magnets are fixed on an inner wall of the outer-ring of the iron shell. The motion part further comprises an iron-ring clinging to an outer wall of the lens holder. The iron-ring and the iron shell define a magnet excitation component. To decrease friction when the motion part moves relative to the fixing part, gaps are defined between the iron shell and the iron-ring, and between the magnetic-iron and the coil. However, the iron-ring and the lens holder are firmly fastened together, and no gap exists therebetween, the dimension of the lens driving apparatus is therefore reduced.

Description

Lens drive

The invention belongs to the technical field of camera, and particularly relates to a lens driving device.

With the continuous development of technology, digital cameras, mobile phone cameras or digital video cameras have become more and more demanding for zooming and focusing. While ensuring high-quality images, the volume requirements for zooming and focusing devices are also More and more strict, zoom and focus devices are moving toward miniaturization.

Now, on the market, the lens driving device is as shown in FIG. 1. The lens driving device 1 includes a lens frame 11, an iron casing 12, a magnet 13, and a coil 14. The coil 14 is fixed to the lens frame 11 and serves as a moving portion together with the lens frame 11. The iron shell 12 has an annular overall structure having an outer ring, an inner ring located in the outer ring, and a yoke connected between the top end of the outer ring and the top end of the inner ring. The magnet 13 is fixed to the inner surface of the outer ring of the iron shell 12, and the inner ring of the iron shell 12 is located between the coil 14 and the lens frame 11. When the coil 14 and the lens frame 11 are moved relative to the iron shell 12 and the magnet 13, in order to prevent friction, a certain gap must be ensured between the coil 14 and the inner ring of the iron shell 12, between the lens frame 11 and the inner ring of the iron shell 12, so that The volume of the lens driving device is limited and cannot be further reduced.

The technical problem to be solved by the present invention is to provide a lens driving device with a small volume.

In order to solve the above technical problem, the present invention provides a lens driving device. The moving portion and the fixed portion are included, the moving portion is located in the fixed portion, and there is a gap between the fixed portion and the moving portion. The moving part includes a coil and a lens holder, and the coil is fixed to the lens frame. The fixing portion comprises a magnet and an iron shell, the iron shell comprises an outer ring and a yoke extending inwardly from the top end of the outer ring, the yoke is provided with a through hole corresponding to the lens frame, and the magnet is fixed on the inner side of the outer ring of the iron shell . The moving part also includes a hoop, which is placed against the outside of the lens frame, and the iron ring and the iron case together form an excitation component.

The lens frame is fixedly connected with the iron ring and the coil as a moving part, and the iron shell and the magnet are fixedly connected as a fixed part, and a gap exists between the fixed part and the moving part, wherein the iron ring and the iron shell form an integral part to become an excitation component. When the moving portion of the lens moves relative to the fixed portion, in order to reduce the friction, a gap is left between the iron shell and the iron ring, between the magnet and the coil, and the iron ring is tightly attached to the lens frame without a gap. Therefore, the reduced gap between the hoop and the lens frame can reduce the size of the lens driving device.

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.

2, 3 and 4, the lens driving device 2 of the 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 there is a gap between the moving portion 21 and the fixed portion 22. The moving portion 21 includes a lens frame 211, a coil 212, a hoop 214, and a lens 213. The lens 213 is fixed in the lens frame 211, and the iron ring 214 and the coil 212 are both The lens frame 211 is abutted and the iron ring 214 is located between the coil 212 and the lens frame 211. The fixing portion 22 includes a magnet 221 and an iron shell 222. The iron shell 222 includes an outer ring and a yoke extending inwardly from the top end of the outer ring. The yoke is provided with a through hole corresponding to the lens frame 211, and the magnet 221 is fixed at The inner side of the outer ring of the iron shell 222, and the iron ring 214 and the iron shell 222 together constitute an exciting component.

The lens frame 211 is fixedly coupled to the iron ring 214 and the coil 212 as a moving portion 21, and the iron shell 222 is fixedly coupled to the magnet 221 as a fixed portion 22, wherein the iron ring 214 and the iron shell 222 are integrally formed as an exciting 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 222 can reduce the volume of the lens driving device 2.

As shown in FIG. 4, in the embodiment of the present invention, the coil 212 can be connected to the iron ring 214 in addition to the lens frame 211, so that the iron ring 214 is located between the lens frame 211 and the coil 212, thereby further eliminating the The gap between the coil 212 and the iron ring 214 allows the volume of the lens driving device 2 to be further reduced.

In the present invention, 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 shape capable of accommodating the iron ring 212. The cross section of the hoop 212 can also be square or otherwise shaped to accommodate the lens frame 211.

As shown in FIGS. 2 and 5, the lens driving device 2 further includes a base 231, an upper spring piece 232 and a lower spring piece 233, an upper spring piece 232 and a lower spring piece. The inner rings of 233 are respectively connected to the two ends of the coil 212, and the outer ring of the upper spring piece 232 and the lower spring piece 233 have contact pieces 234, and the upper spring piece 232 and the lower spring piece 233 pass through the contact piece 234 and the base 231. connection. When the upper spring piece 232 and the lower spring piece 233 are energized, current is introduced into the inner ring through the outer rings of the two spring pieces 232, 233, 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.

As shown in FIG. 2, the base 231 of the lens driving device 2 has a protrusion 241, and the lens frame 211 has a groove 242, and the protrusion 241 and the groove 242 are matched, and can be on the lens frame base 231 and the lens frame. The 211 is evenly arranged. In this embodiment, two pairs of protrusions 241 and grooves 242 are symmetrically disposed, and other arrangements are also possible. By the relative sliding matching of the projection 241 and the recess 242, the lens frame 211 can be prevented from rotating and the lens frame 211 can be prevented from tilting.

An upper insulating sheet 252 is disposed between the upper surface of the iron shell 222 and the upper spring piece 232, and a lower insulating sheet 251 is disposed between the lower surface of the iron shell 222 and the lower spring piece 233. The upper insulating sheet 252 and the lower insulating sheet 251 can prevent When the upper spring piece 232 and the lower spring piece 233 are energized, the iron shell 222 is in contact with the two spring pieces 232, 233 to conduct electricity.

As a preferred embodiment of the present invention, the fixed portion 22 of the lens driving device 2 has four magnets 221, the cross section of the iron shell 222 is a square with a right angle, and the four magnets 221 are respectively fixed to the four lead angles of the square iron shell 222. position.

The number of the magnets 221 may be several or the magnets 221 may be in a ring shape, and the magnets 221 and the iron shells 222 may be arranged in other arrangements as long as the gap between the lens frame 211 and the iron shell 222 can be reduced. Within the scope of protection of the invention.

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‧‧‧Lens frame

12‧‧‧ iron shell

13‧‧‧ magnet

14‧‧‧ coil

2‧‧‧Lens driver

21‧‧‧ sports section

22‧‧‧Fixed part

211‧‧‧Lens frame

212‧‧‧ coil

213‧‧‧ lens

214‧‧‧iron ring

221‧‧‧ Magnet

222‧‧‧ iron shell

231‧‧‧ pedestal

232‧‧‧Upper spring

233‧‧‧ Lower spring piece

234‧‧‧Contacts

241‧‧‧ bumps

242‧‧‧ Groove

251‧‧‧Upper insulation sheet

252‧‧‧lower insulation sheet

1 is a schematic cross-sectional view of a lens driving device provided by the prior art; FIG. 2 is a schematic exploded view of a lens driving device according to an embodiment of the present invention; FIG. 3 is a schematic top view of a lens driving device according to an embodiment of the present invention; A perspective view of a lens driving device according to an embodiment of the present invention is shown in a cross-sectional view along line AA of FIG. 3. FIG. 5 is a perspective view of a moving portion of a lens driving device according to an embodiment of the present invention.

2‧‧‧Lens driver

21‧‧‧ sports section

22‧‧‧Fixed part

211‧‧‧Lens frame

212‧‧‧ coil

213‧‧‧ lens

214‧‧‧iron ring

221‧‧‧ Magnet

222‧‧‧ iron shell

231‧‧‧ pedestal

232‧‧‧Upper spring

233‧‧‧ Lower spring piece

234‧‧‧Contacts

241‧‧‧ bumps

242‧‧‧ Groove

251, 252‧‧ ‧ insulating sheet

Claims (7)

A lens driving device comprising: a moving portion including a coil, a lens frame and a hoop, the coil being fixed on the lens frame, the iron ring abutting on an outer side of the lens frame; and a fixing portion including a magnet And an iron shell fixed to an inner side of the outer ring of the iron shell, the iron shell comprising an outer ring and a yoke extending inwardly from a top end of the outer ring, the yoke being provided with a seat a through hole corresponding to the lens frame; wherein the moving portion is located in the fixed portion, and a gap exists between the fixed portion and the moving portion, and the iron ring and the iron shell together form an excitation Component. The lens driving device of claim 1, 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 1, wherein the lens driving device further comprises a base, an upper spring piece and a lower spring piece, wherein the inner ring of the upper spring piece and the lower spring piece respectively and the coil The two ends of the upper spring piece and the lower spring piece have contact pieces on the outer ring, and the upper spring piece and the lower spring piece are connected to the base through the contact piece. The lens driving device of claim 3, wherein the base has a protrusion, the lens frame has a groove, and the protrusion and the groove are matched. The lens driving device according to claim 1, wherein the lens driving device The fixed portion includes four magnets. The lens driving device of claim 5, wherein the iron shell has a square cross section at a right angle, and the four magnets are respectively fixed at four chamfering positions of the square iron shell. The lens driving device of claim 3, wherein an upper insulating sheet is disposed between the upper surface of the iron shell and the upper spring sheet, and a lower surface of the iron shell is disposed between the lower surface and the lower spring sheet. Insulation sheet.