Patent ID: 8896945
Filing Date: 2014-11-25
Classification: G02B

Abstract:
1. A barrel driving mechanism, comprising: a fixing-barrel, being a hollow barrel-shaped structure, and having a first groove formed on an internal wall of the fixing-barrel, and the first groove having a first stop-position, a first position, and a third position, and a slanted groove extending from the first stop-position to the first position, wherein the fixing-barrel is fixed and a part of the first groove between the first position and the third position is a first slanted groove; a driving-barrel, being a hollow barrel-shaped structure, and installed in the fixing-barrel, and having a second groove formed on an internal wall of the driving-barrel, and the second groove having a second stop-position, a second position, and a fourth position, and a slanted groove extending from the second stop-position to the second position, and having a first guiding protrusion formed on an external wall and inserted into the first groove, such that when the driving-barrel is rotated, the driving-barrel moves a first axial distance, wherein a part of the second groove between the second position and the fourth position is a second slanted groove; and a moving-barrel, being a hollow barrel-shaped structure, installed in the driving-barrel, and having a second guiding protrusion formed on an external wall of the moving-barrel and inserted into the second groove, such that when the driving-barrel is rotated, the moving-barrel moves a second axial distance, and a total displacement of the moving-barrel being equal to a sum of the first axial distance and the second axial distance; wherein when the driving-barrel is rotated, the first guiding protrusion of the driving-barrel is moved a third axial distance along the first slanted groove extending from the first position to the third position, and the second guiding protrusion of the moving-barrel is moved a fourth axial distance along the second slanted groove extending from the second position to the fourth position, and the total displacement of the moving-barrel is equal to the sum of the third axial distance and the fourth axial distance, and the sum of the third axial distance and the fourth axial distance is equal to the displacement of a second-stage focusing of the barrel driving mechanism.