METHOD AND APPARATUS FOR DETERMINING THE THICKNESS OR WIDTH OF WORK PIECES

• US 3,802,774 A
• Filed: 04/10/1972
• Issued: 04/09/1974
• Est. Priority Date: 05/17/1971
• Status: Expired due to Term

• Current Assignee: Dieter Roess, Dieter Rosenberger, Ekkehard Klement, Hans Eschler
• Original Assignee: Dieter Roess, Dieter Rosenberger, Ekkehard Klement, Hans Eschler
• Inventors: Eschler, Hans, Klement, Ekkehard, Roess, Dieter, Rosenberger, Dieter
• Primary Examiner(s): Wilbur, Maynard R.
• Assistant Examiner(s): Buczinski, S. C.
• Application Number:
  US05/242,362
• Time in Patent Office: 729 Days
• Field of Search: 356/1,4,5 250/219TH,219LG,219WD
• US Class Current: 356/637
• CPC Class Codes: G01B 11/043 for measuring length
• CPC Class Codes: G01B 11/046 for measuring width
• CPC Class Codes: G01B 11/06 for measuring thickness ; e.g. of sheet material thickness measurement by thermal means G01B21/085

Abstract

Method and apparatus for measuring the thickness, length or width of work pieces which utilizes lasers and detectors in which the beam of a laser transmitter is shifted until it is detected by the detector so as to indicate a dimension of the work piece. By utilizing laser transmitters and detectors on both sides of the member, the thickness of the member may be detected and by utilizing a laser and detector on both edges of a member the distance between the edges can be detected.

Claims

1. Apparatus for rapidly measuring the width of work pieces comprising:

a first laser beam source for transmitting a first beam substantially normal to a transverse axis adjacent a first edge of said work piece, a first acousto-optical light deflector receiving said first beam and gradually deflecting it as a function of time from a position where it misses said first edge of said work piece to a position where it hits said work piece. a first detector mounted adjacent said first edge and receiving said first beam after it has been reflected by said first edge of said work piece, a second laser beam source for transmitting a second beam substantially normal to a transverse axis adjacent a second edge of said work piece, a second acousto-optical light deflector receiving said second beam and gradually Deflecting it as a function of time from a position where it misses said edge to a position where it hits said work piece, a second detector mounted adjacent said second edge and a known distance from said first detection and receiving said second beam after it has been reflected by said second edge of said work piece, a control connected to said first and second light deflectors to gradually deflect said first and second beams as a function of time, and a computer receiving inputs from said first and second detectors and said control to calculate the width of said work piece.

2. Apparatus according to claim 1 wherein said first transmitting means and said first detector means are mounted adjacent a first edge of said work piece and said first means for changing the radiation angle deflects said first laser beam such that it misses and intercepts said work piece and said first detector means intercepts said first laser beam when it intercepts said work piece, said second transmitting and said second detection means are mounted adjacent a second edge of said work piece and said second means for changing the radiation angle deflects said second laser beam such that it misses and intercepts said work piece and said second detector means intercepts said second laser beam when it intercepts said work piece.

3. Apparatus according to claim 2 wherein said computer means calculates the linear dimension of said work piece from the known distance between said first and second transmitting means and the times that said first and second laser beams intercept said work piece.

4. The method for rapidly measuring the width of a work piece comprising the steps of deflecting linearly as a function of time a first laser beam from a point where it does not engage the work piece to a point where it engages a first edge of the work piece, deflecting linearly as a function of time a second laser beam in a direction opposite to said first beam from a point where it does not engage the work piece to a point where it engages a second edge of the work piece, detecting when said first beam engages said work piece, detecting when said second beam engages said work piece, and computing the width of said work piece from the times when said first and second beams engage said work piece.

5. The method according to claim 4 wherein the linear dimension of the work piece is determined from the times said two impulses are respectively produced by said two detectors when said beams first encounter the edges of said work piece edges and from the known distance between said two deflectors.