Rotary pulse transducer having stator sealing means

• US 3,997,782 A
• Filed: 09/06/1974
• Issued: 12/14/1976
• Est. Priority Date: 09/06/1974
• Status: Expired due to Term

• Current Assignee: Dynapar Corporation (Fortive Corp.)
• Original Assignee: Dynapar Corporation (Fortive Corp.)
• Inventors: Willits, David L.
• Primary Examiner(s): Borchelt, Archie R.
• Assistant Examiner(s): La Roche, E. R.
• Application Number:
  US05/503,618
• Time in Patent Office: 830 Days
• Field of Search: 250/231 SE, 250/231 R, 250/233, 250/236, 250/239, 340/271, 356/138, 356/139, 356/152, 356/172
• US Class Current: 250/231.14
• CPC Class Codes: G01D 5/3473 Circular or rotary encoders
• CPC Class Codes: G01P 13/045 with speed indication
• CPC Class Codes: G01P 3/486 delivered by photo-electric detectors

Abstract

A rotary pulse transducer includes a housing having a pair of halves of similar dimensions. An annular photoelectric stator formed from a plastic sheet is employed as a sealing gasket between the halves of the transducer housing. During assembly of the transducer, the stator may be easily moved relative to the housing for alignment purposes by grasping exterior portions of the stator.

Claims

1. An improved rotary pulse transducer comprising:

a shaft;

a photoelectric rotor mounted on said shaft;

a housing having bearing means rotatably supporting said shaft, said housing being comprised of portions having opposing joinder surfaces;

an annular photoelectric stator located in alignment with said photoelectric rotor, said stator being sealingly interposed between the abutting contiguous joinder surfaces of said housing halves; and

photoelectric sensing means operatively associated with said photoelectric rotor and stator for ascertaining relative rotation of said rotor with respect to said stator.

2. The improved rotary pulse transducer of claim 1 wherein said photoelectric stator extends entirely across said abutting surfaces and has a peripheral edge exposed on the exterior of the housing.

3. The improved rotary pulse transducer of claim 1 wherein said housing portions comprise a pair of housing halves.

4. The improved rotary pulse transducer of claim 1 wherein said opposing joinder surfaces are normal to the axis of said shaft.

5. The improved rotary pulse transducer of claim 3 wherein said halves have substantially identical dimensions.

6. The improved rotary pulse transducer of claim 1 wherein said photoelectric stator is formed of a sheet of film having dimensional stability properties approximating those of the material from which said housing halves is formed.

7. The improved rotary pulse transducer of claim 2 wherein said stator includes means for permitting limited movement of said stator with respect to said housing halves.

8. The improved rotary pulse transducer of claim 7 wherein said housing halves are joined by bolts extending between said halves and through holes in said stator, said holes being greater in size than the dimensions of said bolts.

9. The improved rotary pulse transducer of claim 1 wherein said photoelectric sensing means provides a pair of phase displaced output pulse train signals.

10. A method of assembling and aligning a rotary pulse transducer having a pair of housing portions with contiguous joinder surfaces and containing signal generating means operatively associated with a relatively movable rotor and stator for providing an output signal, said method comprising the steps of:

orienting the portions so that the joinder surfaces are contiguous;

inserting the stator between the contiguous joinder surfaces of the housing portions;

moving the stator with respect to the housing to provide a desired output signal; and

joining the portions and the stator together.

11. The method of claim 10 wherein the stator has an exterior portion extending outside the housing portions and the step of moving the stator further defined as grasping the exterior portions of the stator and moving the stator.

12. The method of claim 10 wherein the method is further defined as loosely joining the housing portions and the stator together so as to permit relative movement between the stator and housing;

moving the stator with respect to the housing, and thereafter securing the halves and the stator together.

13. The method of claim 10 further defined as removing the exterior portion of the stator after moving the stator.

14. The method of claim 10 wherein the signal generating means is further defined as providing a pair of phased displaced output signals and the step of moving the stator is further defined as moving the stator to provide the desired phase displacement between the pair of output signals.

15. The method of claim 10 wherein the rotor is on a shaft mounted in journals in the housing portions, said method including a preliminary step of machining the journals and contiguous joinder surfaces in the same fixture.