Countertriangular optical position sensor

• US 5,078,333 A
• Filed: 10/29/1990
• Issued: 01/07/1992
• Est. Priority Date: 10/29/1990
• Status: Expired due to Fees

• Current Assignee: The United States of America As Represented By The Secretary of Agriculture
• Original Assignee: The United States Of America As Represented By The Secretary Of The Army
• Inventors: Hester, Troy L.
• Primary Examiner(s): GILREATH, STANLEY
• Application Number:
  US07/607,346
• Time in Patent Office: 435 Days
• Field of Search: 242/158 R, 242/158 A, 242/158 B, 242/158 F, 242/158.2, 242/158.4 R, 242/158.4 A, 242/25 R, 226/20, 226/21, 250/548, 250/561, 250/571
• US Class Current: 242/478.2
• CPC Class Codes: B65H 2701/312 Fibreglass strands
• CPC Class Codes: B65H 54/2872 by detection of the incidence angle
• CPC Class Codes: Y10S 242/92 Glass strand winding

Abstract

An optical position sensor for a winding apparatus for winding an optical lament onto a rotating bobbin having means for controlling the winding angle of the filament. The invention comprises a winding angle sensor surface which is rectangular and divided into two surfaces by a diagonal line extending across the path of the filament being wound. The invention includes computer means for receiving signals from each of the halves of the sensor surface for calculating the position of the shadow of the filament crossing over the sensor surface. the sensor head includes means for generating light uniformly on the opposite side of the said filament from said sensor surface.

Claims

1. Optical position sensing apparatus for sensing the position of a moving body as it passes a fixed point, comprising:

a) a two-component photodiode surface disposed at said fixed point for generating an electrical signal in response to light impinging thereon, each of said components being electrically insulated from each other;

b) a light emitting source spaced from said two-component photodiode surface for uniformly illuminating said surface;

c) guide means for guiding said moving body between said light emitting source and said two-component photodiode surface in a position to cast a shadow onto each component of said photodiode surface corresponding to the volume and position of said body; and

d) means for receiving electrical signals generated by each of said photodiode components for comparing said signals and producing a signal indicative of the position of said moving body.

2. Apparatus as set forth in claim 1, wherein said moving body is a running strand.

3. Apparatus as set forth in claim 1, wherein an analog to digital converter is operatively interposed between said two-component photodiode surface and said receiving means.

4. Apparatus as set forth in claim 1, wherein said two-component photodiode surface is rectangular.

5. Apparatus as set forth in claim 1, wherein said photodiode surface is divided into two components by a line which is diagonal to the longitudinal axis of said moving body at said fixed point.

6. Apparatus as set forth in claim 1, wherein said two components of said photodiode surface are mirror images of each other.

7. Apparatus as set forth in claim 1, wherein said photodiode surface is rectangular and is composed of two equal and opposite triangular surfaces.

8. Winding apparatus for winding an optical filament onto a rotating bobbin, having means for controlling the winding angle of said filament, comprising:

(a) a bobbin;

(b) means for supporting said bobbin for rotation and for traversal along its longitudinal axis;

(c) means for rotating said bobbin at a constant rate of rotation about its longitudinal axis;

(d) means for traversing said bobbin along its longitudinal axis at a variable rate;

(e) means for supplying an optical filament to said bobbin spaced a distance therefrom;

(f) an optical position sensor for sensing the angular position of said optical filament as it is wound onto said bobbin, disposed between said supply means and said bobbin, comprising;

(1) a two-component photodiode surface for generating an electrical signal in response to light impinging thereon, each of said components being electrically insulated from each other;

(2) a light source spaced from said two-component photodiode surface for uniformly illuminating said surface; and

(3) guide means for guiding said filament between said light source and said two-component photodiode surface as it is being wound onto said bobbin in a position to cast a shadow onto each component of said photodiode surface corresponding to the volume and the position of said filament;

(g) computer means for receiving signals generated by each component of said photodiode surface and for comparing said signals and calculating the angular position of said filament as it is wound onto bobbin, and for generating control signals for said traversing means to control the traversal rate of said bobbin to wind said filament thereon at a predetermined winding angle.

9. Winding apparatus as set forth in claim 8, wherein said two components photodiode surface is rectangular.

10. Winding apparatus as set forth in claim 9, wherein said photodiode surface is divided into two components by a line which is diagonal to the longitudinal axis of said filament.

11. Winding apparatus as set forth in claim 8, wherein said two components of said photodiode surface are mirror images of each other.

12. Winding apparatus as set forth in claim 8, wherein said two-component photodiode surface is rectangular and is composed of two equal and opposite triangular surfaces.