Automatic tire inflation system

• US 4,431,043 A
• Filed: 10/16/1981
• Issued: 02/14/1984
• Est. Priority Date: 07/31/1981
• Status: Expired due to Fees

• Current Assignee: Ren Acquisition Corp.
• Original Assignee: AM General Corporation
• Inventors: Ellison, Michael J., Goodell, Fred L.
• Primary Examiner(s): Powell, William A.
• Assistant Examiner(s): Bokan, Thomas
• Application Number:
  US06/311,855
• Time in Patent Office: 851 Days
• Field of Search: 152/415, 152/416, 152/417, 152/427, 152/388, 152/389, 152/391, 152/392, 152/401, 152/405, 137/224, 137/351, 301/105 R, 301/126, 301/131, 301/132, 285/111, 285/190, 285/272, 277/152, 277/193, 308/208
• US Class Current: 152/417
• CPC Class Codes: B60C 23/001 Devices for manually or automatically controlling or distributing tyre pressure whilst the vehicle is moving
• CPC Class Codes: B60C 23/00318 on the wheels or the hubs
• CPC Class Codes: B60C 23/00354 Details of valves
• CPC Class Codes: B60C 23/00363 Details of sealings
• CPC Class Codes: B60C 23/00372 characterised by fluid diagrams
• CPC Class Codes: Y10T 137/36 With pressure-responsive pressure-control means
• CPC Class Codes: Y10T 137/6881 Automotive

Abstract

An automatic tire inflation/deflation system for a vehicle (10) is disclosed. Air passageways for the pressurize air are provided internally through the wheel assemblies without cutting into load bearing members. A rotating seal is provided by way of a pair of sealing rings (52,54) located inboard of the hub bearings (32,33) to protect the seals from adverse environmental conditions. A kit for retrofitting vehicles to include an automatic tire inflation/deflation system is also disclosed. Ramp surfaces (90, 91, 92) formed in the hub (30'"'"') are provided to facilitate removal of the bearing assemblies (32, 33).

Claims

1. In an automatic tire inflation/deflation system having a plurality of wheel assemblies for the tires of a vehicle, each wheel assembly having a rotatable portion connected to its associated tire and a nonrotatable portion connected to the vehicle, the improvement comprising:

a nonrotatable elongated annular spindle;

a hub having an enlarged central interior cavity, said hub being mounted for rotation about said spindle on a pair of spaced bearings;

an axle passing through said spindle and connected to the hub;

a pair of annular sealing rings, each sealing ring having a channel-like cross section with a substantially rigid body and a generally horizontally extending flexible lip portion about its inner periphery;

receiving means in the rotating portion of the wheel assembly on both sides of said cavity and inboard of said bearings, adapted to hold the body of said sealing rings laterally in place so that their respective lip portions ride on the spindle; and

means defining a sealed air passageway through which tire inflation air may pass during both inflation and deflation of the tire, said passageway extending from an inlet in inner portions of the spindle to an outlet in exterior portions of the hub, said passageway including an opening in said spindle beween the lip portions of said seals and further including said cavity.

2. The improvement of claim 1 which further comprises:

an annular sleeve having outer edges thereof connected to the hub so as to bridge the central cavity therein, said sleeve having an opening forming part of said air passageway; and

wherein said receiving means are formed in an inner annular surface of said sleeve.

3. The improvement of claim 1 wherein said receiving means are formed directly in an inner annular surface of said hub.

4. The improvement of claims 2 or 3 wherein said receiving means is defined by a pair of shoulders, one on each side of said cavity;

a pair of grooves, each groove being adjacent and outboard of said shoulders; and

a snap ring in each of said grooves.

5. The improvement of claim 1 wherein the lip of each sealing ring includes a radially extending portion made of polytetraflouroethylene riding on the spindle.

6. The improvement of claim 1 wherein outer portions of the body of said sealing rings are coated with a rubbery material.

7. Apparatus for modifying a conventional wheel assembly for use with an automaic tire inflation/deflation system, said wheel assembly including a non-rotatable elongated annular spindle, a hub having a central interior cavity, said hub being mounted for rotation about said spindle on a pair of spaced bearings and an axle passing through said spindle and connected to the hub, wherein said apparatus comprises:

an annular sleeve of sufficient length so that the outer edges thereof may be connected to the hub so as to bridge the central cavity therein inboard of said bearings;

a pair of annular sealing rings with a channel-like cross section, said sealing rings having a generally rigid body and flexible lip portion defining a generally horizontally extending inner periphery of said sealing rings;

receiving means located about an inner surface of said sleeve, adapted to hold the body of said sealing rings in a spaced apart relationship with the lip portions thereof riding on said spindle; and

means defining a sealed air passageway through which tire inflation air may pass during both inflation and deflation of the tire, said passageway including an opening in the spindle between the sealing rings and an opening in the sleeve communicating with said cavity.

8. In an automatic tire inflation/deflation system having a plurality of wheel assemblies for the tires in a vehicle, each wheel assembly having a rotatable portion connected to its associated tire and a nonrotatable portion connected to the vehicle, and means defining a sealed air passageway between an inlet in the nonrotatable portion and an outlet in the rotatable portion, the improvement comprising:

a non-rotatable elongated annular spindle having an interior end connected to the vehicle;

a hub having a central interior cavity, said hub being mounted for rotation about said spindle on a pair of spaced bearings;

an axle passing through spindle and connected to the hub;

an annular sleeve having outer edges thereof connected to the hub so as to bridge the central cavity therein inboard of said bearings;

a pair of sealing rings having their outer peripheral surfaces in contact with said sleeve and inner peripheral surfaces riding on said spindle; and

a sealed air passageway through which tire inflation air may pass during both inflation and deflation of the tire, said passageway extending from an inlet in means defining inner portions of the spindle to an outlet in exterior portions of the hub, said air passageway being defined by a first bore extending substantially the length of said spindle with the inner end of said first bore communication with said inlet, a first opening passing orthogonally through said spindle and meeting said first bore, a second opening through the sleeve into the central cavity, and a second bore extending from the outlet of the hub into the central cavity therein; and

means for connecting said outlet to the tire.

9. In an automatic tire inflation system having a plurality of wheel assemblies for tires in a vehicle, each wheel assembly having a rotatable portion connected to its associated tire and a nonrotatable portion connected to the vehicle, the improvement comprising:

a nonrotatable elongated annular spindle;

a single piece of metal serving as a hub, said hub having an annular surface defining a central passageway through which said spindle passes, said hub being mounted for rotation about said spindle on a pair of spaced bearings;

an axle passing through said spindle and connected to the hub;

said hub having a centrally located enlarged interior cavity surrounding said spindle, first and second grooves on opposite sides of the cavity formed in said annular surface of the hub, first and second shoulders formed in said annular surface between said cavity and the first and second grooves, respectively, said grooves and shoulders being located between said pair of bearings;

first and second snap rings, one in each of said first and second grooves;

a pair of annular sealing rings each sealing ring having a channel-like cross section with a substantially rigid body and a generally horizontally extending lip portion about its inner periphery, one sealing ring being laterally held in place between said first shoulder and first snap ring and the other sealing ring being held in place between said second shoulder and second snap ring, with the lip portions of the respective sealing rings riding on said spindle;

means defining a sealed air passageway from an inlet in inner portions of the spindle and an outlet in the hub; and

whereby said sealing rings provide air seals to prevent air from escaping between the central cavity in the rotating hub and the nonrotating spindle, said sealing rings being located inboard of the bearing to protect them from adverse environmental conditions.

10. The improvement of claim 9 wherein said air passageway is defined by first bore extending substantially the length of said spindle, with the inner end of said first bore communicating with said inlet, a first opening passing orthognonally through said spindle between said sealing rings and meeting said first bore, and a second bore extending from the outlet of the hub into the central cavity therein.