Tire pressure indicator

DETAILED DESCRIPTION It is accordingly a primary object of the present invention to provide a tire pressure indicator with a pressure sensor arrangement by which tire pressure can be effectively detected and indicated and by which, even if said indicator is damaged, no escape of the air pressure in the tire will occur.
This and other objects of the present invention are achieved by the provision of a tire pressure indicator which comprises: a hollow cylindrical body having a closed side at the upper end thereof and an open side at the lower end thereof; a light indicating mechanism, which comprises a light bulb, a first conductor member, and a light cover, disposed at the closed side of said hollow cylindrical body; a piston container with a closed side at the upper end thereof and an open side at the lower end thereof screw-connected to a threaded portion of said light bulb in said hollow cylindrical body; a sleeve member having a closed side at the lower end thereof and a piston unit, which includes a mercury cell, a pressure spring positioned under said mercury cell, and a sliding member located on the lower end of said pressure spring, separately disposed in the hollow cylindrical body and located around said piston container with said piston unit being movably positioned in the inner chamber of said piston container and controllable to be raised or lowered therein by the air pressure of an associated tire; a pressure sensor which is composed of a film member, a second conductor member and an air-channel member, disposed under said sliding member and positioned on the closed side of said sleeve member for being coupled with the tire valve of an associated tire and operated by the air pressure of said tire in connection with said piston unit; and a supporting base with an air cavity in the middle thereof connected to the open side of said hollow cylindrical body in conjunction with the air-channel member of said pressure sensor for being secured on the inflating valve of said tire along with said hollow cylindrical body; whereby, when said tire pressure indicator is connected to the air inflating valve of a tire, the pressure of a tire can be effectively detected and indicated therewith