Slip ring amplifier

• US 5,952,762 A
• Filed: 03/18/1998
• Issued: 09/14/1999
• Est. Priority Date: 03/18/1997
• Status: Expired due to Fees

• Current Assignee: Michigan Scientific Corporation
• Original Assignee: Michigan Scientific Corporation
• Inventors: Menosky, Jeffrey A., Larsen, Hugh W.
• Primary Examiner(s): Ramirez, Nestor
• Assistant Examiner(s): Waks, Joseph
• Application Number:
  US09/040,818
• Time in Patent Office: 545 Days
• Field of Search: 310/232, 310/248, 310/68 B, 340/540, 318/475
• US Class Current: 310/232
• CPC Class Codes: B60R 16/027 between relatively movable parts of the vehicle, e.g. between steering wheel and column devices for measuring, signalling or controlling tyre pressure or temperature specially adapted for mounting on vehicles B60C23/00
• CPC Class Codes: G01L 3/108 involving resistance strain gauges
• CPC Class Codes: H01R 39/08 Slip-rings
• CPC Class Codes: H01R 39/64 Devices for uninterrupted current collection

Abstract

A slip ring amplifier has a rotor fixedly mountable on a rotatable tubular member and carrying an amplifier mounted in a recess connected to a sensor fixedly mountable on the rotatable member. A stationarily mounted stator is coupled to the rotor by bearings. A slip ring brush block with leaf contacts is mounted in a cavity between the rotor and the stator. End caps are mounted on opposite ends of the rotor and the stator and fixed to one of the rotor and stator. Labyrinth seals are disposed between each end cap and the stator. In one embodiment, an electrolytic fluid fills the cavity between the rotor and stator and surrounds the brush block and leaf contacts. In another embodiment, a dielectric coating is provided on the leaf contacts. Conductors extend from the leaf contacts through the stator to a connector fixedly mounted on the stator.

Claims

1. A slip ring amplifier apparatus mountable on a rotatable tubular member comprising:

sensor means mounted on a tubular member for sensing a parameter of the tubular member;

a rotor adapted to be coupled to the tubular member;

amplifier means, carried on the rotor and connected to the sensor means, for amplifying an output of the sensor means;

a stator stationarily positioned adjacent to the rotor;

a cavity formed between the rotor and the stator; and

a slip ring mounted on one of the rotor and stator and electrically engagable with a leaf contact mounted on the other of the rotor and stator, and

wherein the one slip ring is carried on the rotor and disposed in the cavity between the rotor and the stator; and

the leaf contact is carried on the stator and is electrically engagable with the one slip ring; and

an electrical conductor extending from the leaf contact externally of the stator.

2. The apparatus of claim 1 further comprising connector means, connected to the electrical conductor extending from the contact, for connecting the electrical conductor to an external circuit.

3. The apparatus of claim 1 further comprising;

an electrolytic fluid disposed in the cavity and surrounding the slip ring and the leaf contact.

4. The apparatus of claim 1 further comprising:

a dielectric coating disposed on the leaf contact.

5. The apparatus of claim 1 further comprising:

seal means disposed between the rotor and the stator for sealingly coupling the rotor and the stator.

6. The apparatus of claim 1 further comprising;

biasing means for biasing the leaf contact into engagement with the slip ring.

7. The apparatus of claim 1 further comprising:

bearings disposed between the rotor and the stator.

8. The apparatus of claim 7 further comprising:

biasing means for biasing the bearings and the rotor into engagement.

9. The apparatus of claim 8 further comprising:

annular shoulders formed on the rotor, the bearings engaging the shoulders.

10. The apparatus of claim 1 further comprising:

first and second end caps fixedly mounted on opposed ends, respectively, of the rotor and the stator.

11. The apparatus of claim 10 wherein each of the first and second end caps comprise:

radially spaced inner and outer ends;

a first seal disposed between the inner ends of each of the first and second end caps and the tubular member; and

a second seal disposed between the outer ends of each of the first and second end caps and the stator.

12. The apparatus of claim 11 wherein:

the first seals include annular elastomeric members adapted to be disposed in engagement with the tubular member; and

the first and second end caps have a tapered surface engagable with the elastomeric members to forcibly urge the elastomeric members into sealing engagement with the tubular member.

13. The apparatus of claim 11 wherein:

the first seals comprise elastomeric seals fixably mounted by an adhesive coating to the tubular member.

14. The apparatus of claim 11 wherein the second seals comprise labyrinth seals.

15. The apparatus of claim 14 further comprising;

O-rings sealingly disposed between the labyrinth seals and outer ends of the stator and the first and second end caps.

16. The apparatus of claim 10 further comprising:

each of the first and second end caps including a plurality of circumferentially spaced bores; and

a plurality of outwardly extending bores formed on opposite sides of the rotor and alignable with bores in the first and second end caps for receiving fasteners therethrough to fixedly join the first and second end caps to opposite sides of the rotor, respectively.