Device for measuring displacement

• US 5,033,300 A
• Filed: 06/13/1990
• Issued: 07/23/1991
• Est. Priority Date: 06/20/1989
• Status: Expired due to Term

• Current Assignee: Murata Manufacturing Co Limited
• Original Assignee: Murata Manufacturing Co Limited
• Inventors: Murata, Michihiro, Matsuo, Kenji, Kumada, Akira
• Primary Examiner(s): Cuchlinski, Jr., William A.
• Assistant Examiner(s): NOT, DEFINED
• Application Number:
  US07/537,174
• Time in Patent Office: 405 Days
• Field of Search: 73/304 R, 73/290 R, 73/301, 73/313, 73/304 C, 324/149, 324/453, 377/17, 377/19, 377/21, 377/45, 364/550, 364/561, 364/562, 356/21, 356/28, 356/358, 356/375, 33/706, 33/707, 33/708
• US Class Current: 73/304.00R
• CPC Class Codes: G01B 7/02 for measuring length, width or thickness G01B7/004, G01B7/12 take precedence
• CPC Class Codes: G01F 23/242 Mounting arrangements for electrodes
• CPC Class Codes: G01F 23/243 Schematic arrangements of probes combined with measuring circuits

Abstract

A device for measuring displacement comprises a pair of sensor elements of which output voltage changes stepwise in dependency upon displacement of a measurement object, a differentiating circuit for detecting time points at which the output voltage of the pair of sensor elements suddenly changes, and a counter for counting the sudden change time points of the output voltage detected by the differentiating curcuit.

Claims

1. A device for measuring displacement of an object, comprising:

displacement sensor means for producing an output voltage that changes stepwise in dependency upon displacement of the object;

differentiating means connected to receive said output voltage and provide output pulses at times corresponding to sudden output voltage changes; and

counter means for counting said output pulses, whereby the count of said counter is a measure of said displacement.

2. A device for measuring displacement as set forth in claim 1, wherein said differentiating means is comprised of a differentiating circuit operative to output positive and negative differential pulses;

and wherein said counter means is comprised of an up-down counter connected to count up and down in response to the output of positive and negative differential pulses, respectively, by said differentiating circuit.