Rail gage apparatus

• US 3,864,039 A
• Filed: 07/12/1973
• Issued: 02/04/1975
• Est. Priority Date: 07/12/1973
• Status: Expired due to Term

• Current Assignee: Robert W. Wilmarth
• Original Assignee: Robert W. Wilmarth
• Inventors: Wilmarth, Robert W.
• Primary Examiner(s): McGraw, Vincent P.
• Assistant Examiner(s): Rosenberger, Richard A.
• Application Number:
  US05/378,510
• Time in Patent Office: 572 Days
• Field of Search: 33/287,332 356/156,167,172
• US Class Current: 356/625
• CPC Class Codes: B61K 9/08 Measuring installations for surveying permanent way applications of measuring apparatus or devices for track building purposes E01B35/00; measuring techniques G01
• CPC Class Codes: G01B 11/14 for measuring distance or clearance between spaced objects or spaced apertures G01B11/26 takes precedence; rangefinders G01C3/00

Abstract

Apparatus which can be affixed to the underside of revenue producing trains which will produce an electrical signal which is a measure of the gage or distance between the rails such that the condition and maintenance requirements of the track can be determined without interfering with the revenue service of the train.

Claims

1. Rail gage apparatus comprising in combination with a wheeled vehicle for traveling along two rails having opaque rail heads:

light projection means mounted on said vehicle illuminating the base of both of the rails;

light receiver means positioned above said opaque rail heads but not in physical contact therewith such that the amount of reflected light received is dependent upon the shadows cast by the positions of the gage side of said opaque rail heads; and

means for converting said received light into continuous positional data signals representing the gage between rails.

2. Rail gage apparatus according to claim 1 which further includes means for modulating the light projection means and signal processing means connected to the output of the light receiver means for processing the detected signals to discriminate against unwanted light signals.

3. Rail gage apparatus according to claim 2 wherein said means for processing the detected signal comprises synchronous gating means.

4. Rail gage apparatus according to claim 2 wherein said means for processing the detected signal comprises filtering means at the modulation frequency.