Claims:I Claim,
1. “External Air Passage for Central Tire Inflation system” is an alternate air passage that passes parallel to the wheel hub to inflate the automotive wheels using central tire inflation system comprises of:
a. Transverse small air passage in the wheel hub (12).
b. Outlet valve (5) attached with the wheel hub (9).
c. External air passage model (4).
d. Inlet valve (3) attached with the wheel rim.
e. Transverse small air passage in the wheel rim (10).
f. Rubber member in the head bolts.
2. The external air passage as claimed in claim 1a, wherein a small air passage is transverse positioned to the wheel hub (12) which connects CTIS (7) (Central Tire Inflation System) with the external air passage (4) using outlet valve (5).
3. The external air passage as claimed in claim 1b, wherein the outlet valve (5) is placed exactly below the CTIS (7) that connects CTIS (7) via wheel hub (9) small air passage with the external air passage model (4).
4. The external air passage as claimed in claim 1c, wherein external air passage model (4) is positioned between outlet valve (5) and inlet valve (3).
5. The external air passage as claimed in claim 1d, wherein the inlet valve (3) is placed in the inner surface of the rim that extends with a small air passage in the rim to lead towards the outer surface of the rim (10).
6. The external air passage as claimed in claim 1, wherein the strength of the wheel hub (9) is protected by using small duct through the wheel hub for the CTIS air channel.
7. The external air passage as claimed in claim 1e, wherein a small air passage is transverse to the wheel rim which connects external air passage (4) with tire inflation.
8. The external air passage as claimed in claim 1f, wherein the rubber member (21) in the head bolts near inlet (3) and outlet valve (5) will severe as an integral member to retain form, fit and function during differential deflection between rim and disc due to thickness and load variations.
9. The external air passage as claimed in above claims, wherein it is provided with valves, bolts and couplings for easy attachment and detachment from the wheels.
, Description:FIELD OF INVENTION
[0001] The present invention is related to the field of manufacturing automotive wheels in accordance with the implementation of CTIS (central tire inflation system) and more particularly the introduction of external air passage with the wheel hub for the central tire inflation system.
BACK GROUND OF INVENTION
[0002] It is known that tires on a vehicle, such as truck trailer, should be properly inflated for ease of control of the vehicle, fuel consumption, its safety, and to procure long life of the expensive tires.
[0003] Frequent manual pressure monitoring and its regulation is cumbersome, time consuming and not economical. To overcome these disadvantages inbuilt CTIS (central tire inflation system) equipped automotive vehicles are designed nowadays. Automated CTIS regulating system is used to regulate the vehicle pressure during on road without stopping the vehicle.
[0004] Central tire inflation system (CTIS) (7) is originally developed for military applications, in particular for military applications concerning off-road military trucks and trailers. However CTIS (7) system flourished even in non-military vehicles such as commercial and agricultural vehicles.
[0005] A CTIS (7) typically comprises a compressed air source located on-board the vehicle and connected to one or more tires. Tire pressure can therefore be adjusted by operating the CTIS (7). The CTIS delivers compressed air to tire supply lines.
[0006] The tire supply lines are the air passage which connects CTIS (7) with the air inlet to the tire rim. In the prior art, CTIS is the post manufacturing attachment to the wheel which has inflation associated elements such as pressure sensor air tube and air inlet tube that are exposed outside of the wheel. This causes tire imbalance, potential breakage or damage to the exposed inflation components and also it raises the cost of overall inflation system. It has been customary to employ with certain types of vehicles connected to a central tire inflation system (CTIS), for example an on board pump for producing compressed air to be transferred through various wheel mounted valves and hoses to the tubeless tires that are mounted on the vehicle’s wheel. So it essentiates the CTIS to be included within the manufacturing process.
[0007] The US Patent No.6474383 employs CTIS equipped automotive wheel (23). Here the air passage for central tire inflation system is designed internally (24), (25) within the wheel hub (9). In general, vehicle wheels are supposed to bear full weight of the vehicle, to withstand the impact of centrifugal force, momentum at the time of turning on the brake, road surface gradient. When an air passage is made along the wheel hub (9), then wheel strength will be reduced.
[0008] In this representation it is difficult to withstand the above said mechanical stresses and the possibilities of air crack initiation are higher. An air crack in the wheel hub will create wheel break down in age.
[0009] The proposed invention is designed to overcome these complications and provide hassle free smart external air passage for (CTIS) central tire inflation system.

SUMMARY OF THE INVENTION
[0010] The present invention consists of external air passage and fitting accessories for an automotive wheel air inflation system. The central air inflation system has air conduits to connect wheels of the vehicle for the tire inflation. The external air passage includes an outlet valve (5) which is attached to the wheel hub and inlet valve (3) which is attached to the wheel rim.
[0011] From the wheel hub outlet valve (5) an external air passage (4) is fitted. The L-shaped (18) air passage pipe from the wheel hub outlet valve (5), extended parallel to the wheel hub and pass towards wheel rim. In the wheel hub a small air duct (12) links CTIS with the outlet valve (5) and in the rim another small air duct is formed transversely to host air inlet valve (3). At this juncture the external air passage tube is fixed between outlet and inlet valve.
[0012] Thus in the way the air path starts from the CTIS (7), pass through the small transverse air duct (12) in the wheel hub, and from the hub outlet valve, the L-shaped external passage leads to the inlet valve and reach tire inflation through small air duct (10) in the wheel rim.
OBJECT OF THE INVENTION
[0013] A main objective of the invention is to provide a hassle free air passage model for the central tire inflation system which will not weaken the strength of the wheel hub.
[0014] An another objective of the invention is to provide compact and air tight passage for central air inflation system used in automotive wheels.
[0015] Further objective of the invention is to provide easy maintenance of the air passage model by using easily detachable valves, bolts, couplers and nuts.
DETAILED DESCRIPTION
[0016] The present invention relates to positioning of air passage in central tire inflation system for use with pneumatic tubeless tires, and more particularly the alternate air passage link (4) which is external to wheel hub (9) for use with an air inflation system.
[0017] In the available inbuilt CTIS the air passage is made within the wheel hub which reduces the strength of the wheel. Hence, an alternate air passage is designed to retain the wheel strength and to revamp CTIS process.
[0018] An alternate air passage is made parallel and just external to the wheel hub (9). The proposed external air passage (4) for tire inflation system is exactly positioned opposite to CTIS (7) (central tire inflation system) and has a conjunction with an outlet valve. A small transverse air duct (12) in the wheel hub (9) connect the CTIS (central tire inflation system) (7) with the outlet valve (5). The outlet valve is affixed in the path of small transverse air duct (12) in the wheel hub (9).
[0019] From the outlet valve (5) an external air passage (4) is attached which has a perpendicular bent (18) near to the outlet valve (5) and elongated parallel to the wheel hub (9). The external air passage is further extending towards the wheel rim. In the rim small air duct (10) is attached with inlet valve (3). The inlet valve allows the air passage between tire and external air passage cylinder. The outer side of the inlet valve (3) has a radially extending air duct (2) for air inflation.
[0020] The external air passage is initiated from the CTIS (7), pass through the small transverse air duct (12) in the wheel hub, and from the wheel hub outlet valve (5) , the L-shaped external passage (4) leads the air passage to the inlet valve and reach tire inflation through small air duct (10) in the wheel rim.
[0021] Differential deflection will be predominant between rim and disc regions due to variations in thickness and loading. Variations will be profound during light or no load conditions. To adjust with these mechanical jolts, bolts which are attached with the inlet (3) and out let valve (5) are equipped with a rubber member (21). The said rubber member will serve as an integral member to retain its original form and function during regular wear and tear.
[0022] To control air flow to a tire on the rim the transverse wall has therein a first air duct (10), inlet valve which opens at one end on the outer periphery of the rim for communication with the interior tire mounted thereon, and opens at its opposite end on the outboard or outwardly facing side. From the outwardly facing side the customized external air passage (4) leads the path towards the CTIS.
[0023] A second air duct (12) is formed in the wheel hub to open at one end towards the customized external air passage, and to open at its opposite end on the opposite or inboard side of the wheel hub for connection to a central inflation system.
[0024] The control signal is executed either by manual or automatic using the CTIS (central tire inflation system) through external air passage. The CTIS has the control program for the automatic operation and also has digital pressure guage and control switches for manual operation.
[0025] The proposed external air passage works on simple mechanism with valves, air tube, bolts and couplings. But the external air passage (4) gives air tight insulation to hold the tire pressure without any leak.
[0026] The external air passage can be easily attached or detached from the wheel during installation and maintenance.
BRIEF DESCRIPTION OF DRAWINGS
[0027] Figure 1: is a cross sectional view of the automotive wheel, which is equipped with the external air passage (4) for central air inflation system. In the diagram part 1 represents the outside wheel, part 2 the radially extending air duct for tire inflation, part 3 shows the inlet valve that positioned across rim air duct (10), part 4 is the external air passage for CTIS (7), part 5 is the outlet valve from the CTIS (7) which is positioned across wheel hub interlinking CTIS (7) with the external air passage (4), part 6 represents ‘O’ rings, part 7 is the CTIS (central tire inflation system), part 8 is the inside wheel, part 9 is the wheel hub, part 10 is the small air duct transverse to the wheel rim, part 11 is the perpendicular elbow bend for air passage, part 12 is the small air duct transverse to the wheel hub.
[0028] Figure 2: shows the front view of unique designed external air passage (4) equipped wheel. In the figure part 13 represents wheel rim outer circumference, part 14 represents the provisions for bolts, part 15 is the vent hole,
[0029] Figure 3: is the perspective view of external air passage for CTIS (4). In the diagram part 16 represents the pipe valve fitting towards tire, part 17 represents the valve fitting towards the wheel hub, part 18 represents the perpendicular L bent, and part 19 and 20 represents the pipe coupler.
[0030] Figure 4: is the dismantled organisation of external air passage components representing the rubber membrane (21), lateral screws (22) and air passage couplers (19) and (20),
[0031] Figure 5: the part (23) represents the internal air passage for CTIS (Central Tire Inflation System) in the available in Prior art.
[0032] Figure 6: It represents the focussed view of the external air passage in the Prior art for CTIS (Central Tire Inflation System). Part (24) and (25) represents the internal air passage in the prior art.