Lens focusing device

摘要

A lens focusing device includes a lens holder, a winding fitted around the lens holder, and an outer case enclosing the lens holder therein. The outer case includes an outer wall portion, and multiple inner wall portions connected to the outer wall portion via multiple connecting portions. The inner wall portions are located between the lens holder and the winding, and respectively include an inner surface, an outer surface, and a first and a second side surface. The lens holder is formed on an outer face with confining areas, each of which includes a main surface and a first and a second raised side surface respectively facing against the inner surface and the first and second side surfaces, so that the inner wall portions are limited to move relative to the lens holder only within the confining areas. Therefore, the lens focusing device is impact-resistant and undue-twisting protected.

主权项

1. A lens focusing device, comprising:
a lens holder for holding a lens therein to move along a direction of a light axis and having an outer face, on which at least one confining area is formed; a winding being fitted around the outer face of the lens holder; an outer case enclosing the lens holder therein, and including an outer wall portion, at least one connecting portion, and at least one inner wall portion; wherein the connecting portion is connected to between the outer wall portion and the inner wall portion, and the inner wall portion is located between the lens holder and the winding; wherein the inner wall portion and the connecting portion are arranged at the corner of the outer wall portion; and at least four magnets, wherein the inner wall portion each includes an inner surface, an outer surface, and a first and a second side surface connected to between the inner and the outer surface; and the inner surface being faced against the lens holder while the outer surface is faced against the winding; wherein each of the magnets is arranged in a corner space defined by the inner surface of the inner wall portion and the outer wall portion; wherein the confining area each includes: a main surface of the lens holder faced against the inner surface of the inner wall portion of the outer case, wherein the main surface and the inner surface are flat; wherein the outer surface is faced against a flat surface of a magnet such that the inner wall portion is sandwiched between the main surface and the magnet; a first raised side surface located at one lateral edge of the main surface to face against the first side surface of the inner wall portion; and a second raised surface located at another lateral edge of the main surface to face against the second side surface of the inner wall portion; and wherein the at least one inner wall portion of the outer case is located corresponding to the at least one confining area on the outer face of the lens holder, and a clearance is existed between the first raised side surface and the second raised surface, and the inner wall portion into the clearance for limiting a space within which the lens holder can move left or right rotation and protecting the lens holder against biasing or undue twisting under impact of an external force thereon; wherein a first clearance between the inner surface of the inner wall portion and the main surface of the lens holder is smaller than a second clearance between the outer surface of the inner wall portion and the winding.