Title:
METHOD AND DEVICE FOR READING STAMPED MARK ON METALLIC PLATE
Document Type and Number:
Japanese Patent JPS63208701
Kind Code:
A
Abstract:
PURPOSE:To obtain a high-reliability device which is free from mis-detection by deciding the level of the time-division detected difference signal between the signal outputs of two adjacent sensors among plural magnetic sensors which are arranged in array. CONSTITUTION:A magnetic sensor 3 consisting of plural (S1-Sn) (n) sets of sensors arrayed in a line is installed on the metallic plate 1 which has the stamped pattern 2. A time-division differential circuit 4 detects difference signal between couples of adjacent sensors of this magnetic sensor 3 in the order of a difference signal between the sensors S1 and S2 and the difference signal between the sensors S2 and S3 up to a difference signal between the sensors Sn-1 and Sn. Those difference signals are inputted to an upper-limit comparator 5 which generates an output when a signal is larger than a specific value and a lower-limit comparator 6 which generates an output when the signal is smaller than another specific value, and their outputs are supplied to the set and reset terminals of an RSFF7.
Inventors:
WASA YASUHIRO
Application Number:
JP4191487A
Publication Date:
August 30, 1988
Filing Date:
February 24, 1987
Export Citation:
Assignee:
NEC CORP
International Classes:
G01B7/28; G01B7/00; G11B5/02; (IPC1-7): G01B7/28; G11B5/02
Domestic Patent References:
| JPS626161A | 1987-01-13 | |||
| JPS5439173A | 1979-03-26 |
Attorney, Agent or Firm:
Naoki Kyomoto (2 outside)