Integrated ball cage
AssigneesDigital Imaging Systems GmbH, .
InventorHubert Utz
Life of this patent
Estimating the term…
Abstract
Systems and methods to reduce manufacturing and assembly costs for measures to avoid blocking or creeping ball conditions for linear ball bearings are disclosed. In preferred embodiments two linear ball bearings, a fixed ball bearing and a non-locating ball bearing, are applied to guide movements of a lens barrel of camera modules. Ball cages, which are integrated either in a moving part or in a fixed part of an actuator, are lowering manufacturing and assembly costs. A constant magnetic preload force is applied to both ball bearings to keep the bearings together in case of a mechanic shock. Ball bearing contact points of the fixed ball bearing are shifted asymmetrically by a small angle to withstand horizontal preload forces.
Claims30
A method to reduce manufacturing and assembly costs for measures to avoid blocking ball conditions for linear ball bearings, comprising the following steps:
- (1) providing a camera module wherein movements of a lens barrel are driven by at least one linear actuator and are guided by a first and a second ball bearing;
- (2) inserting each ball of the ball bearings in an own integrated ball cage, which is integrated in the moving lens barrel;
- (3) selecting for the first ball bearing a fixed ball bearing, wherein ball bearing contact points are shifted by a small angle in direction of a preload force applied to the first ball bearing;
- (4) selecting for the second ball bearing a non-locating ball bearing;
- (5) deploying each ball bearing in a suitable position in order to be able to receive the preload force;
- and
- (6) providing the preload force towards the bearings in order to hold the bearings together in case of a mechanical shock and to have the balls always touching their surface to roll on.
An arrangement of ball bearings preventing blocking and creeping of balls for guiding movements of a lens barrel comprises:
- a fixed ball bearing, wherein ball bearing contact points are shifted by a small angle in direction of a constant preload force applied and each ball of the fixed ball bearing rolls in an own integrated ball cage, which is integrated in the moving lens barrel;
- a non-locating ball bearing, wherein each ball of the non-locating ball bearing rolls in an own integrated ball cage, which is integrated in the moving lens barrel;
- and
- a magnetic pre-load device providing a constant pre-load force on the fixed ball bearing and on the non-locating ball bearing in order to hold the bearings together in case of a mechanical shock and to have the balls always touching their surface to roll on.
Dependencies are inferred from the claim text.