Automatic tire inflation/deflation system

PURPOSE: To automatically adjust internal pressure of a vehicular tire by a simple and inexpensive structure by switching a valve according to the difference between a target value and an actual value of tire internal pressure, and selectively communicating a tire with a compressed air source or an exhaust port. CONSTITUTION: In a system 100 for automatically adjusting internal pressure of a vehicle tire, an output 138 related to desired internal pressure of the tire is generated by a manual control means 101. An output 174 related to actual internal pressure of the tire is generated by a plurality of tire pressure monitoring means 152, 165 connected to a manifold 104. Moreover, a valve 168 having an exhaust port 194, an input port 192 connected to the output side of a compressed air source 108, and an output port connected to the tire through a manifold 104 is provided. The valve 168 is energized between the position to be comminuted with the compressed air source 108 and the position to be communicated with the exhaust port 194 according to the difference between respective outputs 138, 174 in order to inflate/deflate the tire. COPYRIGHT: (C)1990,JPO