This invention relates to air supply systems and in particular, to a new and improved air supply system incorporating a track along which a vehicle may move and pick up air from the track. The invention will be described herein as used with an air bearing transporter such as is shown by way of example in U.S. Pat. No. 3,796,279. However the air supply system of the present invention is not limited to use with air bearing transporters and may be utilized for supplying air under pressure to any type of vehicle or other load while moving or stationary.
An air bearing transporter has a plurality of air bearings which produce an air film between the transporter and the floor or other surface resulting in very low friction permitting the transporter and its load to be moved with a small force. The transporter requires a supply of air under pressure which may be provided by an onboard compressor or by a hose connection or by an air supply in the floor over which the transporter moves.
A prior air supply system with an air track is shown in U.S. Pat. No. 3,820,467. The air track comprises one or more ducts in the floor with openings along the upper surface of the duct for air flow into the vehicle positioned above the ducts. In this prior art system, the air passages in the upper wall of the ducts are open at all times, resulting in continuous air flow through all openings even though the vehicle is positioned over only a few of the openings. Such a system requires a relatively high rating for the compressed air source while wasting most of the compressed air.
In order to meet this disadvantage, various types of air supply systems have been developed utilizing control valves for the air flow. However the large number of valves required makes these systems expensive, and the valves are subject to damage and jamming and require continuous maintenance.
Another form of air track is shown in U.S. Pat. No. 3,722,424. In one embodiment, the spaced openings along the duct are closed by a sealing strip which is moved downward exposing the openings in the duct by the vehicle as it moves along the track. An alternative embodiment utilizes a pair of resilient tubes for closing a continuous opening in the duct, with a support structure carried by the vehicle and moving between the resilient tubes on rollers providing air flow from the duct to the vehicle. Another prior art system is shown in U.S. Pat. No. 3,190,460, utilizing a resilient duct with lips moved inward to an open position by a suction applied to the duct.
It is an object of the present invention to provide a new and improved air supply system which is simple to manufacture, install and maintain, relatively inexpensive and trouble free, and having substantially no air losses. A further object is to provide a new and improved air supply system utilizing an air track for the floor and a cooperating probe for the vehicle, with the probe being engageable with and disengageable from the air track as desired permitting control of movement of the vehicle along the track and permitting movement of the vehicle away from the track as desired. An additional object is to provide an air track and movable probe combination which can operate with the track in an overhead or side wall position. Other objects, advantages, features and results will more fully appear in the course of the following description.