Missing link/part detector employing scanning engine
AssigneeBorgWarner Inc.
InventorMark E. Patton
Life of this patent
Estimating the term…
Abstract
A bar code reader missing link detection system for detection of missing, defective or misaligned chain links in assembled or in-process chains includes a light source for illuminating one or more chain links of a chain, a light sensitive diode array for detecting an image of a fixed scan line, produced by the light source, and a lens system for focusing incoming light produced by the light source onto the diode array, wherein the system is arranged such that the bar code reader reflects light from one or more of the chain links onto the diode array, and the diode array is continuously scanned, digitized, and the data obtained thereby interpreted to detect missing chain links.
Claims32
A method of detecting missing parts in a workpiece comprising a plurality of parts, comprising the steps of:
- a) moving the workpiece, in which the workpiece is a parallel-link chain, and the missing part is a link in the chain relative to a scanning engine;
- b) detecting a line image across the workpiece with scanning engine, producing a signal output representative of the line image;
- c) deriving a processed signal from the signal output of the scanning engine;
- d) comparing the processed signal to a reference signal representing a workpiece without missing parts;
- and
- e) indicating if the processed signal does not match the reference.
A missing part detection system for detection of missing parts in a workpiece having a plurality of parts, comprising:
- a) a light source for illuminating the workpiece, in which the workpiece is a parallel-link chain, the missing parts are links in the chain, and there are two scanning engines, one each to scan guide row and non-guide row links of a chain;
- and
- b) a light sensitive array for detecting a line image of the workpiece, produced by said light source, having a signal output representative of the detected line image;
- and
- c) a signal processing circuit having an input coupled to the signal output of the light sensitive array, and an output, such that the signal output of the light sensitive array is compared to a reference signal representative of a complete workpiece without missing parts, and the output of the signal processing circuit producing a signal when the comparison indicates a part is missing.
A method of detecting missing parts in a workpiece comprising a plurality of parts, comprising the steps of
- a) moving the workpiece relative to a scanning engine;
- b) detecting a line image across the workpiece with scanning engine, producing a signal output representative of the line image;
- c) deriving a processed signal from the signal output of the scanning engine;
- d) comparing the processed signal to a reference signal representing a workpiece without missing parts;
- and
- e) indicating if the processed signal does not match the reference;
- wherein the step of deriving a processed signal comprises converting the signal output of the scanning engine into a number;
- wherein the reference is a number, and the step of comparing comprises comparing the two numbers;
- and
- wherein the number is a binary number in which each bit represents a detection or non-detection of a part.
A method of detecting missing parts in a workpiece comprising
- a plurality of parts, comprising the steps of:
- a) moving the workpiece relative to a scanning engine;
- b) detecting a line image across the workpiece with scanning engine, producing a signal output representative of the line image;
- c) deriving a processed signal from the signal output of the scanning engine;
- d) comparing the processed signal to a reference signal representing a workpiece without missing parts;
- and
- e) indicating if the processed signal does not match the reference;
- in which the workpiece is moved in a start-stop motion relative to the reader, and the line image is detected while the workpiece is stationary.
A missing part detection system for detection of missing parts in a workpiece having a plurality of parts, comprising:
- a) a light source for illuminating the workpiece;
- b) a light sensitive array for detecting a line image of the workpiece, produced by said light source, having a signal output representative of the detected line image;
- and
- c) a signal processing circuit having an input coupled to the signal output of the light sensitive array, and an output, such that the signal output of the light sensitive array is compared to a reference signal representative of a complete workpiece without missing parts, and the output of the signal processing circuit producing a signal when the comparison indicates a part is missing;
- wherein signal processing circuit utilizes mathematical integration of an output signal from said light sensitive array and calculates an area under a measured output curve, and the reference is a voltage.
A missing part detection system for detection of missing parts in a workpiece having a plurality of parts, comprising:
- a) a light source for illuminating the workpiece;
- b) a light sensitive array for detecting a line image of the workpiece, produced by said light source, having a signal output representative of the detected line image;
- and
- c) a signal processing circuit having an input coupled to the signal output of the light sensitive array, and an output, such that the signal output of the light sensitive array is compared to a reference signal representative of a complete workpiece without missing parts, and the output of the signal processing circuit producing a signal when the comparison indicates a part is missing;
- wherein the signal processing circuit counts a number of level transitions in the signal output of the light sensitive array, and the reference is a preset value;
- and
- wherein the signal processing circuit includes a variable analysis window that only counts changes within said analysis window, such that signals outside the window are ignored by said analysis system.
A missing part detection system for detection of missing parts in a workpiece having a plurality of parts, comprising:
- a) a light source for illuminating the workpiece;
- b) a light sensitive array for detecting a line image of the workpiece, produced by said light source, having a signal output representative of the detected line image;
- and
- c) a signal processing circuit having an input coupled to the signal output of the light sensitive array, and an output, such that the signal output of the light sensitive array is compared to a reference signal representative of a complete workpiece without missing parts, and the output of the signal processing circuit producing a signal when the comparison indicates a part is missing;
- in which the light source is located behind the workpiece, such that the light from the light source silhouettes the workpiece, and the line image is detected by light blocked by parts or passed where there are no parts.
Dependencies are inferred from the claim text.