US 12,078,515 B2
Linear displacement absolute position encoder
Haiping Guo, Zhangjiagang (CN); Weifeng Shen, Zhangjiagang (CN); Songsheng Xue, Zhangjiagang (CN); and Haochen Li, Zhangjiagang (CN)
Assigned to MultiDimension Technology Co., Ltd., Zhangjiagang (CN)
Appl. No. 17/904,414
Filed by MultiDimension Technology Co., Ltd., Zhangjiagang (CN)
PCT Filed Feb. 9, 2021, PCT No. PCT/CN2021/076130
§ 371(c)(1), (2) Date Aug. 17, 2022,
PCT Pub. No. WO2021/164632, PCT Pub. Date Aug. 26, 2021.
Claims priority of application No. 202020177471.0 (CN), filed on Feb. 17, 2020.
Prior Publication US 2022/0404171 A1, Dec. 22, 2022
Int. Cl. G01D 5/16 (2006.01); G01D 5/14 (2006.01)
CPC G01D 5/16 (2013.01) [G01D 5/142 (2013.01)] 16 Claims
OG exemplary drawing
 
1. A linear displacement absolute position encoder used for measuring displacement in a direction of a rail of a tested apparatus, the linear displacement absolute position encoder comprising:
a base,
a magnetoresistive sensor array,
an encoding strip, and
a back magnet;
wherein the encoding strip is fixed on the base and extends in the direction of the rail of the tested apparatus, the encoding strip includes a magnetic material block having recesses and protrusions corresponding to an array of encoding bits used to encode different positions, the array of encoding bits in the encoding strip includes P rows where P is an integer more than one and M columns where M is an integer more than one, each of the encoding bits having a value set based on a corresponding recess or protrusion in the magnetic material block, each of the P rows forming an encoding channel with M encoding bits corresponding to a unique pattern of recesses and protrusions to uniquely encode position information;
wherein the back magnet is configured to generate a non-uniform magnetic field around the encoding strip to magnetize the encoding strip; and
wherein the magnetoresistive sensor array is arranged between the encoding strip and the back magnet in a non-contact manner, the magnetoresistive sensor array includes magnetoresistive sensors in N rows where N is a positive integer and M columns, and the magnetoresistive sensor array is configured to be used to determine the position information using the M encoding bits for at least one of the P rows.