Zoom lens apparatus and bearing block assembly
AssigneeEastman Kodak Company
InventorsJohn G. Weigand, Christopher J. Kralles, Noel L. Reyner
Life of this patent
Estimating the term…
Abstract
A zoom lens apparatus having a first pair of substantially parallel guide rods. A pair of carriage assemblies are mounted to the first pair of parallel guide rods each having lens element. A pair of lead screws are provided for driving the carriage assemblies. The screws are each mounted to the apparatus by a bearing block assembly such that the longitudinal axis of the lead screw is substantially parallel to the first pair of guide rods. The bearing block constrains the movement of the first lead screw along the longitudinal axis. A zero constraint threaded drive coupling is provided with each lead screw for moving the carriage along the guide rods. A motor is provided for rotating each of the drive screws.
Claims15
A zoom lens apparatus comprising:
- a pair of substantially parallel guide rods;
- a first carriage slideably mounted to said pair of parallel guide rods;
- a first lens element secured to said first carriage;
- a first lead screw having a longitudinal axis, said first lead screw being mounted to said apparatus by a first bearing block assembly such that said longitudinal axis is substantially parallel to said pair of guide rods, said first bearing block assembly constraining the movement of said first lead screw along said longitudinal axis;
- a first threaded drive nut coupling which is threadingly engaged to said first lead screw for movement along the axis of said first lead screw, said first threaded drive nut coupling being connected to said first carriage so as to move said first carriage along said first pair of guide rods, said first threaded drive nut coupling providing substantially zero axial play;
- a first motor having a drive shaft for driving said first lead screw, said drive shaft of said motor being connected to said first bearing block assembly and is mounted to said apparatus by a flex member;
- a second carriage slideably mounted to said first pair of parallel guide rods;
- a second lens element secured to said second carriage;
- a second lead screw having a longitudinal axis, said second lead screw being mounted to said apparatus by a second bearing block assembly such that said longitudinal axis is substantially parallel to said pair of guide rods, said second bearing block assembly constraining the movement of said second lead screw along said longitudinal axis;
- a second threaded drive nut coupling which is threadingly engaged to said second lead screw for movement along the axis of said second lead screw, said second threaded drive nut coupling being connected to said second carriage so as to move said second carriage along said first pair of guide rods, said second threaded drive nut coupling providing substantially zero axial play;
- and
- a second motor having a drive shaft for driving said second lead screw, said shaft of said motor being connected to said second bearing block assembly and is mounted to said apparatus by a flex member.
A bearing block assembly for use in connecting two axially aligned shafts and constraining the shafts along the axis, said assembly comprising;
- an annular mounting block having a opening, said opening having a first annular bore section of a first diameter and a second annular bore section of a second diameter, said first and second bore sections being substantially concentric with each other, said second diameter being greater than said first diameter;
- a first radial bearing disposed within said first annular bore section and a second radial bearing disposed within said second annular bore section, said first and second radial bearings being secured within said opening;
- and
- a shaft coupling member having a flange member, said flange being disposed between said first and second radial bearings, a spring member is disposed between said flange and said first or second radial bearing so as to apply a separating force between said first and second radial bearings.
Dependencies are inferred from the claim text.