Automatic tire inflation system

Claim 2

In an automatic tire inflation 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 non- rotatable portion connected to the vehicle, the improvement comprising: a nonrotatable elongated annular spindle (24); a hub (30, 30') having an enlarged central interior cavity (34, 34'), said hub being mounted for rotation about said spindle(24)on a pair of spaced bearings (32, 33); . an axle (12) passing through said spindle (24) and connected to the hub (30, 30'); a pair of annular sealing rings (52, 54), each sealing ring having a channel-like cross section with a substantially rigid body (93) and a generally horizontally extending flexible lip portion (94) about its inner periphery; receiving means in the rotating portion of the wheel assembly on both sides of said cavity (34, 34') and inboard of said bearings (32, 33), adapted to hold the body (93) of said sealing rings (52, 54) laterally in place so that their respective lip portions (94) ride on the spindle (24); and means defining a sealed air passageway from an inlet (62) in inner portions of the spindle (24) and an outlet (64) in exterior portions of the hub (30, 30'), said passageway including an opening (76) in said spindle (24) between the lip portions (94) of said seals (52,. 54) and further including said cavity (34, 34').

Claim 3

The improvement of Claim 1 which further comprises: an annular sleeve (42) having outer edges thereof connected to the hub (30) so as to bridge the central cavity (34) therein, said sleeve (42) having an opening (78) forming part of said air passageway; and wherein said receiving means are formed in an inner annular surface of said sleeve (42).

Claim 4

The improvement of Claim 1 wherein said receiving means are formed directly in an inner annular surface (83) of said hub (30').

Claim 5

, 4. The improvement of Claims 2 or 3 wherein said receiving means is defined by a pair of shoulders (48, 50; 85, 87), one on each side of said cavity (34, 34') a pair of grooves (88,89), each groove being adjacent and outboard of said shoulders; and snap rings (44,46) in said grooves.

Claim 6

The improvement of Claim 1 wherein a portion (95), of the lip (94) riding on the spindle (24) is made of polytetraflouroethylene.

Claim 7

The improvement of Claim 1 wherein outer portions of the body.(93) of said sealing rings (52,54) are coated with a rubbery material (96) .

Claim 8

Apparatus for modifying a conventional wheel assembly for use with an automatic tire inflation system, said wheel assembly including a non- rotatable elongated annular spindle (24), a hub (30) having a central interior cavity (34), said hub being mounted for rotation about said spindle (24) on a pair of spaced bearings (32,33) and an axle (12) passing through said spindle (24) and connected to the hub (30), wherein said apparatus comprises: an annular sleeve (42) of sufficient length so that the outer edges thereof may be connected to the hub (30) so as to bridge the central cavity (34) therein inboard of said bearings (32,33); a pair of annular sealing rings (52,54) with a channel-like cross section, said sealing rings having a generally rigid body (93) and flexible lip portion (94) defining a generally horizontally extending inner periphery of said sealing rings; and receiving means located about an inner surface of said sleeve (42), adapted to hold the body (93) of said sealing rings in a spaced apart relationship with the lip portions (94) thereof riding on sai,d spindle (24); and an opening (78) in said sleeve (42) to provide an air passageway into said cavity (34) for air coming from an opening (76) in the spindle (24).

Claim 9

Apparatus for modifying a conventional wheel assembly for use with an automatic tire inflation system, said wheel assembly including a non- rotatable elongated annular spindle (24), a hub (30) having a central interior cavity (34), said hub being mounted for rotation about said spindle (24) on a pair of spaced bearings (32,33) and an axle (12) passing through said spindle (24) and connected to the hub (30), wherein said apparatus comprises: an annular sleeve (42) of sufficient length so that the outer edges thereof may be connected to the hub (30) so as to bridge the central cavity (34) therein inboard of said bearings (32,33); a pair of annular sealing rings (52,54) with a channel-like cross section, said sealing rings having a generally rigid body (93) and flexible lip portion (94) defining a generally horizontally extending inner periphery of said sealing rings; and receiving means located about an inner surface of said sleeve (42), adapted to hold the body (93) of said sealing rings in a spaced apart relationship with the lip portions (94) thereof riding on sai,d spindle (24); and an opening (78) in said sleeve (42) to provide an air passageway into said cavity (34) for air coming from an opening (76) in the spindle (24).

Claim 10

In an automatic tire inflation 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 non- rotatable portion connected to the vehicle, and means defining a sealed air passageway between an inlet in the non-rotatable portion and an outlet in the rotatable portion, the improvement comprising: a non-rotatable elongated annular spindle (24) having an interior end (26) connected to the vehicle (28); a hub (30) having a central interior cavity (34), said hub being mounted for rotation about said spindle (24) on a pair of spaced bearings (32,33); an axle (12) passing through spindle (24) and connected to the hub (30); an annular sleeve (42) having outer edges thereof connected to the hub (30) so as to bridge the central cavity (34) therein inboard of said bearings (32,33) ; a pair of sealing rings (52,54) having their outer peripheral surfaces in contact with said sleeve (42) and inner peripheral surfaces riding on said spindle (24); and a sealed air passageway from an inlet (62) in the inner portions of the spindle (24) and an outlet (64) in exterior portions of the hub(30}, said air passageway being defined by a first bore (66) extending substantially the length of said spindle (24) with the inner end of said first bore communication with said inlet (62), a first opening (76) passing orthogonally through said spindle (24) and meeting said first bore, a second opening (78) through the sleeve (42) into the central cavity (34), and a second bore (80) extending from the outlet (64) of the hub (30) into the central cavity (34) therein; and means (18,84) for connecting said outlet (64) to the tire (16).

Claim 11

In an automatic tire inflation 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 non- rotatable portion connected to the vehicle, and means defining a sealed air passageway between an inlet in the non-rotatable portion and an outlet in the rotatable portion, the improvement comprising: a non-rotatable elongated annular spindle (24) having an interior end (26) connected to the vehicle (28); a hub (30) having a central interior cavity (34), said hub being mounted for rotation about said spindle (24) on a pair of spaced bearings (32,33); an axle (12) passing through spindle (24) and connected to the hub (30); an annular sleeve (42) having outer edges thereof connected to the hub (30) so as to bridge the central cavity (34) therein inboard of said bearings (32,33) ; a pair of sealing rings (52,54) having their outer peripheral surfaces in contact with said sleeve (42) and inner peripheral surfaces riding on said spindle (24); and a sealed air passageway from an inlet (62) in the inner portions of the spindle (24) and an outlet (64) in exterior portions of the hub(30}, said air passageway being defined by a first bore (66) extending substantially the length of said spindle (24) with the inner end of said first bore communication with said inlet (62), a first opening (76) passing orthogonally through said spindle (24) and meeting said first bore, a second opening (78) through the sleeve (42) into the central cavity (34), and a second bore (80) extending from the outlet (64) of the hub (30) into the central cavity (34) therein; and means (18,84) for connecting said outlet (64) to the tire (16).

Claim 12

The improvement of Claim 8 wherein said means includes an air line (18) connected between said outlet (64) and said tires (16), an inlet valve stem (20) in said line (18) for manually supplying air to the tire from an external source, and a manually actuable shut off valve (22) between the stem (20) . and the outlet (64) from the hub to selectively prevent air from passing between the tire (16) and the air passageway in the hub when desired.

Claim 13

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 (24); a single piece of cast metal serving as a hub (30'), said hub (30') having an annular surface (83) defining a central passageway through which said spindle (24) passes, said hub being mounted for rotation about said spindle (24) on a pair of spaced bearings (32,33) ; an axle (12) passing through said spindle (24) and connected to the hub (30'); said hub having a centrally located enlarged interior cavity (34') surrounding said spindle (24), first and second grooves (88,89) on opposite sides of the cavity (34') formed in said annular surface (83) of the hub (30'), first and second shoulders (85,87) formed in said annular surface (83) between said cavity (34') and the first and second grooves, respectively, said grooves and shoulders being located between said pair of bearings (32,33); a pair of snap rings (44,46) , one in each of said first and second grooves; means defining a sealed air passageway from an inlet (62) in inner portions of the spindle (24) and an outlet (64) in exterior portions of the hub (30'); and whereby said sealing rings provide air seals to prevent air from escaping between the central cavity (34') in the rotating hub (30') and the nonrotating spindle (24), said sealing rings being located inboard of the bearing (32,33) to protect them from adverse environmental conditions.

Claim 14

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 (24); a single piece of cast metal serving as a hub (30'), said hub (30') having an annular surface (83) defining a central passageway through which said spindle (24) passes, said hub being mounted for rotation about said spindle (24) on a pair of spaced bearings (32,33) ; an axle (12) passing through said spindle (24) and connected to the hub (30'); said hub having a centrally located enlarged interior cavity (34') surrounding said spindle (24), first and second grooves (88,89) on opposite sides of the cavity (34') formed in said annular surface (83) of the hub (30'), first and second shoulders (85,87) formed in said annular surface (83) between said cavity (34') and the first and second grooves, respectively, said grooves and shoulders being located between said pair of bearings (32,33); a pair of snap rings (44,46) , one in each of said first and second grooves; means defining a sealed air passageway from an inlet (62) in inner portions of the spindle (24) and an outlet (64) in exterior portions of the hub (30'); and whereby said sealing rings provide air seals to prevent air from escaping between the central cavity (34') in the rotating hub (30') and the nonrotating spindle (24), said sealing rings being located inboard of the bearing (32,33) to protect them from adverse environmental conditions.

Claim 15

The improvement of Claim 10 wherein said air passageway is defined by first bore (66) extending substantially the length of said spindle (24), with the inner end of said first bore communicating with said inlet (62), a first opening (76) passing orthogonally through said spindle (24) between said sealing rings (52, 54) and meeting said first bore, and a second bore (80) extending from the outlet (64) of the hub (30') into the central cavity (34') therein.

Claim 16

A kit for retrofitting vehicles'to include an automatic tire inflation system, said kit comprising: a control box (101) adapted to be mounted in the cab of the vehicle, said control box including manually actuable selector means (102) for selecting one of a plurality of preset air pressure settings for the tires; and I an inflate/deflate valving assembly (142) adapted to be mounted on the vehicle, said assembly including a first (166) and second (168) interconnected shuttle valves operating in a master/slave relationship, said first valve (166) being operative to selectively supply pilot air to control the position of the second valve (168) depending upon the pressure differential between actual and desired tire pressures applied to said first valve (166), said second valve (168) being responsive exclusively to the pilot air to either completely shuttle to one position for inflating the tires or to another position for deflating the tires.

Claim 17

A kit for retrofitting vehicles'to include an automatic tire inflation system, said kit comprising: a control box (101) adapted to be mounted in the cab of the vehicle, said control box including manually actuable selector means (102) for selecting one of a plurality of preset air pressure settings for the tires; and I an inflate/deflate valving assembly (142) adapted to be mounted on the vehicle, said assembly including a first (166) and second (168) interconnected shuttle valves operating in a master/slave relationship, said first valve (166) being operative to selectively supply pilot air to control the position of the second valve (168) depending upon the pressure differential between actual and desired tire pressures applied to said first valve (166), said second valve (168) being responsive exclusively to the pilot air to either completely shuttle to one position for inflating the tires or to another position for deflating the tires.

Claim 18

The kit of Claim 12 which further comprises: a static pressure tank (152) adapted to be connected to the tires for providing a representation of the actual pressure within the tires.

Claim 19

The kit of Claim 12 which further includes means for modifying a conventional wheel assembly to provide a sealed air passageway between an inlet in nonrotating portions thereof and an outlet in rotating portions thereof.

Claim 20

A hub for a vehicle comprising: an annular member (30') having an inner peripheral surface (83) with at least one portion thereof adapted to receive a bearing assembly (32); and a plurality of spaced ramps (90, 91, 92) formed in said surface interiorly of said bearing receiving portion; , whereby said bearings may be easily removed by a device having fingers adapted to contact interior portions of the bearing assembly through said ramps.

Claim 21

A hub for a vehicle comprising: an annular member (30') having an inner peripheral surface (83) with at least one portion thereof adapted to receive a bearing assembly (32); and a plurality of spaced ramps (90, 91, 92) formed in said surface interiorly of said bearing receiving portion; , whereby said bearings may be easily removed by a device having fingers adapted to contact interior portions of the bearing assembly through said ramps.

Claim 22

In an automatic tire inflation system for a vehicle, the improvement comprising: manually actuable selector means (102) in the vehicle cabin for selecting one of a plurality of preset air pressure settings (75 psi, 30 psi, 10 psi) for the tires; and control means (100) for adjusting and constantly maintaining the pressure in the tires (16) at the selected preset pressure without further manual intervention.

Claim 23

In an automatic tire inflation system for a vehicle, the improvement comprising: manually actuable selector means (102) in the vehicle cabin for selecting one of a plurality of preset air pressure settings (75 psi, 30 psi, 10 psi) for the tires; and control means (100) for adjusting and constantly maintaining the pressure in the tires (16) at the selected preset pressure without further manual intervention.

Claim 24

The improvement of claim 16 wherein said selector means comprises a multi-position toggle valve.

Claim 25

The improvement of claim 17 wherein said control means comprises: air compressor means (106) for supplying compressed air; a plurality of pressure regulators (120, 122, 124) corresponding in number to the number of positions of said selector device, said pressure regulators having inlets coupled for receipt of a portion of said air from the compressor (106) and being adapted to provide preselected fixed air pressures at their respective outlets; means (130, 132) cooperating with the toggle valve (102) for coupling the fixed air pressure from one of the pressure regulators to a first line (138) to serve as control pressure as a function of the position of the toggle valve (102); inflate/deflate assembly means (142) including a first shuttle valve (166) having first (170) and second (172) control in- puts, an inlet port (176), and first (184) and second (186) outlet ports, operative to selectively connect said inlet port (176) to said first (184) and second (186) outlets depending upon the relative pressure between the first (170) and second (172) control inputs; said first control input (170) being coupled to said first line (138) supplying the control pressure, said second control input (172) being connected to the static pressure within the tires (16), said input port (176) being connected for receipt of pilot air over a second line (146) from the compressor (106) whereby said first shuttle valve (166) operates to couple the pilot air to said second outlet port (16) when the control pressure exceeds the static pressure, and further operates to couple the pilot air to said first outlet port (184) when static pressure exceeds the desired control pressure, with pilot air being blocked from either of the outlet ports (184, 186) when the control pressure and static pressure are in equilibrium; said inflate/deflate valve means further including a second shuttle valve (168) having first (188) and second (190) control inputs coupled to the second (186) and first (184) outlet ports of the first shuttle valve (166), respectively; said second shuttle valve having an input port (192) coupled to said air compressor (106), an exhaust port (194), and an outlet port (198) coupled to inlets for each tire (16), whereby said compressed air is coupled to said tires to inflate same when pilot air is coupled to the first control input (190), and wherein said exhaust port (194) is coupled to said tires (16) for deflating same when the pilot air is coupled to the second control input (188) of the second shuttle valve (168).

Claim 26

The improvement of claim 18 wherein said static pressure is supplied by a static pressure tank (152) coupled between the inlets to the tires and the second control input (172) of the first shuttle valve (166) and wherein a fixed orifice (165) is provided between the tire inlets and the tank (152) to maintain the pressure in the tank (152) at the same pressure as in the tires.

Claim 27

The improvement of claim 18 wherein said air compressor (106) is coupled to an air brake system air tank (108) whose outlet is coupled to the input port (192) of said second shuttle valve (168).

Claim 28

The improvement of claim 20 which further comprises a priority valve (196) connected to the outlet of,the brake system air tank (108), operative to prevent air pressure therefrom to be diverted to the tires (16) when the pressure in the air tank (108) falls below a given pressure.

Claim 30

The improvement of claim22 wherein said toggle valve (102) includes an exhaust port (103) which is connected to the control input (170) of the first shuttle valve (166) when the low pressure setting (10 psi) is selected whereby the higher pessure at the control input (170) is released back through first line (138), fourth valve (132), third valve (130) and then out of exhaust port (103), with the low pressure then passing through fourth valve (132) after the released pressure has fallen significantly below the selected low, pressure.

Claim 32

In an automatic tire inflation system, the improvement comprising: an inflate/deflate valving assembly (142) for quickly inflating or deflating the tires, said assembly including first (166) and second (168) interconnected shuttle valve means operating in a master-slave relationship, said first valve (166) being operative to selectively supply pilot air to control the positioning of the second valve depending on the pressure differential between actual and desired tire pressures applied to said first valve, said second valve being responsive exclusively to the pilot air to either completely shuttle to one position for inflating the tires or to another position for deflating the tires.

Claim 33

In an automatic tire inflation system, the improvement comprising: an inflate/deflate valving assembly (142) for quickly inflating or deflating the tires, said assembly including first (166) and second (168) interconnected shuttle valve means operating in a master-slave relationship, said first valve (166) being operative to selectively supply pilot air to control the positioning of the second valve depending on the pressure differential between actual and desired tire pressures applied to said first valve, said second valve being responsive exclusively to the pilot air to either completely shuttle to one position for inflating the tires or to another position for deflating the tires.

Claim 34

The improvement of claim 24 wherein said actual tire pressure is provided by way of a static pressure tank (152) connected to the tires through a restricted orifice (165). :

Claim 35

A central tire inflation system for a vehicle comprising: a control box (101) mounted in a cabin of the vehicle, said control box including a multi-positioned toggle valve (102), a plurality of pressure regulators (120, 122, 124) for providing fixed air pressures, a first outlet line (136) for supplying one of the fixed air pressures, and a second outlet line (144) for supplying pilot air; a brake system air tank (108); a manifold (104) having an inlet and a plurality of outlets providing connections to the tires; a static pressure tank (152) connected through a fixed orifice (165) to the manifold (104), and an inflate/deflate assembly including a first shuttle valve (166) with a first control input (170) connected to first line (136) and a second control input (172) connected to an output of the static pressure tank (152), operative to selectively supply pilot air from second line (144) to a first output port (184) or second output port (186) depending upon the pressure differential between its control inputs (170, 172); a second shuttle valve (168) with a first control input (190) connected to the second output port (186) of first valve .(166) and a second control input (188) connected to the first output port (184), said second valve (168) having an exhaust port (194), an input port (192) connected to an output of said brake tank (108), and an output port (198) connected to the inlet of said manifold (104), operative to selectively connect the manifold (104) to the brake tank (108) for inflating the tires or to the exhaust port (194) for deflating the tires as a function of the pilot air supplied to its control inputs (188,190).

Claim 36

A central tire inflation system for a vehicle comprising: a control box (101) mounted in a cabin of the vehicle, said control box including a multi-positioned toggle valve (102), a plurality of pressure regulators (120, 122, 124) for providing fixed air pressures, a first outlet line (136) for supplying one of the fixed air pressures, and a second outlet line (144) for supplying pilot air; a brake system air tank (108); a manifold (104) having an inlet and a plurality of outlets providing connections to the tires; a static pressure tank (152) connected through a fixed orifice (165) to the manifold (104), and an inflate/deflate assembly including a first shuttle valve (166) with a first control input (170) connected to first line (136) and a second control input (172) connected to an output of the static pressure tank (152), operative to selectively supply pilot air from second line (144) to a first output port (184) or second output port (186) depending upon the pressure differential between its control inputs (170, 172); a second shuttle valve (168) with a first control input (190) connected to the second output port (186) of first valve .(166) and a second control input (188) connected to the first output port (184), said second valve (168) having an exhaust port (194), an input port (192) connected to an output of said brake tank (108), and an output port (198) connected to the inlet of said manifold (104), operative to selectively connect the manifold (104) to the brake tank (108) for inflating the tires or to the exhaust port (194) for deflating the tires as a function of the pilot air supplied to its control inputs (188,190).