Abstract: Provided is an electromagnetic induction type displacement detection apparatus in which influence of a change in magnetic flux received by a receiving device can be suppressed. An electromagnetic induction type displacement detection apparatus 1 includes a scale including a scale coil and a head 3 relatively moving with respect to the scale. The head 3 includes a transmitting device 4 that generates magnetic flux in the scale coil, and a receiving device 5 that includes a first receiving unit 51 and a second receiving unit 52 each receiving the change in the magnetic flux and in which the first receiving unit 51 and the second receiving unit 52 are arranged to be shifted from each other along a measurement direction.
Abstract: A combined optical and capacitive absolute positioning encoding system uses a plurality of metallized strips deposited onto a glass scale substrate. A movable transceiver is positioned adjacent to the scale. The transceiver generates interrogating electrical an optical signals which interact with the scale. The movable transceiver also carries with it receiver mechanisms for receiving the signals after interaction with the scale. Signal processing electronics are provided to determine the relative positions of the scale and transceiver by comparing the transmitted, interrogating signals with the received signals. The system is able to determine the relative positions of the scale and transceiver even if power to the system is interrupted, or if the scale and transceiver are moved relative to one another very rapidly.
Type:
Grant
Filed:
February 26, 1991
Date of Patent:
July 6, 1993
Assignee:
Mitutoyo
Inventors:
Nils I. Andermo, Tracy E. Hanley, Philip S. Lane