Scale
AssigneeRenishaw PLC
InventorsJames Reynolds HENSHAW, Finlay Jonathan EVANS, George Frederick BRAMTON
Life of this patent
Estimating the term…
Abstract
A scale arrangement for a measurement encoder includes a scale and a thermal displacement relief structure. The thermal displacement relief structure includes an intermediate member and a first thermal displacement relief layer for attaching the scale to the intermediate member. The coefficients of thermal expansion of the intermediate member and the scale conform to the following: - 3 × 10 - 6 K - 1 ≤ CTE ( intermediate member ) - CTE ( scale ) ≤ 6 × 10 - 6 K - 1 .
Claims23
A scale arrangement for a measurement encoder, the scale arrangement comprising a scale and a thermal displacement relief structure, the thermal displacement relief structure comprising an intermediate member, a first thermal displacement relief layer, and a second thermal displacement relief layer, the first thermal displacement relief layer for attaching the scale to the intermediate member, wherein the coefficients of thermal expansion of the intermediate member and the scale conform to the following:
- -
- 3
- ×
- 10
- -
- 6
-
- K
- -
- 1
- ≤
- CTE
-
- (
- intermediate
-
- member
- )
- -
- CTE
-
- (
- scale
- )
- ≤
- 6
- ×
- 10
- -
- 6
-
- K
- -
- 1
- .
A scale arrangement as claimed in 10, wherein the scale comprises a metal or metal alloy, the intermediate member comprises a metal or metal alloy, and the second intermediate member comprises carbon fibre.
-24. (canceled)
A scale arrangement for a measurement encoder, the scale arrangement comprising a metal or metal alloy scale and a thermal displacement relief structure, the thermal displacement relief structure comprising an intermediate member, a first thermal displacement relief layer and a second thermal displacement relief layer, the first thermal displacement relief layer for attaching the scale to the intermediate member, wherein the intermediate member comprises a metal or metal alloy.
-27. (canceled)
Dependencies are inferred from the claim text.