Structure for measuring the average diameter of an approximately circular cross-section of an object

• US 3,897,156 A
• Filed: 11/14/1973
• Issued: 07/29/1975
• Est. Priority Date: 07/27/1971
• Status: Expired due to Term

• Current Assignee: Leon H. Chasson
• Original Assignee: Leon H. Chasson
• Inventors: Chasson, Leon H.
• Primary Examiner(s): Stolwein, Walter
• Application Number:
  US05/415,565
• Time in Patent Office: 622 Days
• Field of Search: 250/223,222,560 356/156,157,159,160,167,199 144/312
• US Class Current: 356/638
• CPC Class Codes: G01B 11/043 for measuring length
• CPC Class Codes: G01B 11/105 using photoelectric detection means
• CPC Class Codes: G01B 5/0035 Measuring of dimensions of trees

Abstract

A plurality of discrete marker sensors and a multiplicity of linear arrays are used to measure selected dimensions of passing objects. One linear array is used in conjunction with selected marker sensors to measure the lengths of objects and the remaining marker sensors and linear arrays are used to measure selected dimensions of objects perpendicular to their lengths. The system is particularly useful in measuring the lengths and selected diameters of logs.

Claims

1. Structure to produce a measure of the average diameter of a selected, approximately circular, cross-section of an object, which comprises:

means for producing a first set of signals representing a first diameter of said object at said selected cross-section;

means for producing a second set of signals representing a second diameter of said object at said selected cross-section; and

means for processing said first set of signals and said second set of signals to produce said measure of said average diameter;

wherein said means for producing a first set of signals and said means for producing a second set of signals each comprise a linear array of photosensitive elements formed on a chip of semiconductor material;

lens means for focusing light representing a diameter of said object on said photosensitive elements; and

means for scanning said photosensitive elements to generate a sequence of pulses representing the incident energy detected by adjacent photosensitive elements in said linear array, said pulses comprising a set of signals representing said diameter of said object.

2. Structure as in claim 1 wherein said means for producing a first set of signals and said means for producing a second set of signals each include in addition;

means of illuminating said object thereby to generate said light representing said diameter of said object.

3. Structure for producing a measure of the average diameter of a selected, approximately circular, cross-section of an object and a measure of the shift in location of said cross-section from its expected location, which comprises:

means for producing a first set of signals representing a first diameter of said object at said selected cross-section;

means for producing a second set of signals representing a second diameter of said object at said selected cross-section;

means for processing said first set of signals and said second set of signals to produce said measure of said average diameter; and

means for measuring the shift in location of said cross-section from its expected location by measuring the difference between the first diameter and the second diameter of said cross-section measured by said means for producing a first set of signals and said means for producing a second set of signals.

4. Structure as in claim 3 wherein said object is a log.

5. Structure for measuring the curvature of a substantially cylindrical object possessing a center line through the center of all cross-sections of said object, said structure comprising:

means for producing a plurality of first sets of signals representing a plurality of first diameters of said object at a plurality of selected cross-sections;

means for producing a plurality of second sets of signals representing a plurality of second diameters of said object at said plurality of selected cross-sections; and

means for measuring the curvature of said object by calculating from said plurality of first sets of signals and said plurality of second sets of signals the shifts in the locations of the center line of said object at said plurality of selected cross-sections of said object as said object, on the one hand, and said means for producing a plurality of first sets of signals and said means for producing a plurality of second sets of signals, on the other hand, move relative to each other.

6. Structure as in claim 5 wherein said substantially cylindrical object is a log.

7. Structure to produce a measure of the average diameter of a selected, approximately circular, cross-section of an object, which comprises:

means for producing a first set of signals representing a first diameter of said object at said selected cross-section;

means for producing a second set of signals representing a second diameter of said object at said selected cross-section; and

means for processing said first set of signals and said second set of signals to produce said measure of said average diameter;

wherein said means for producing a first set of signals is oriented substantially perpendicular to said means for producing a second set of signals; and

wherein said means for producing a first set of signals has a first center line, said means for producing a second set of signals has a second center line, and said means for producing a first set of signals and said means for producing a second set of signals are located such that said first center line and said second center line each make an angle of approximately 45* with the vertical.

8. Structure as in claim 7 wherein said means for producing a first set of signals and said means for producing a second set of signals each comprises a linear sequence of photo-sensitive devices, each photo-sensitive device being capable of being operated to store an amount of charge representative of the total light from a given segment of space occupied by said object being measured by said linear array means.

9. Structure as in claim 8 wherein the segment of space represented by the light impinging on any one photo-sensitive element in said means for producing a first set of signals or in a means for producing said second set of signals corresponds to a linear distance along the respective dimension being measured of said object.

10. Structure as in claim 7 wherein the nominal distances from said means for producing a first set of signals and said means for producing a second set of signals to the center of said cross section are approximately equal.

11. Structure as in claim 7 wherein said means for producing a first set of signals and said means for producing a second set of signals each comprise a linear array of photo-sensitive elements.