Detector of the inflation pressure of motor vehicle tires
First Claim
1. In a tire pressure detector for motor vehicles, comprising a pressure switch which is to be fastened to a circumference of a wheel rim and is actuated by air pressure in the tire for monitoring the tire pressure and which comprises an electrically conductive switching diaphragm;
- a member forming a reference pressure chamber closed toward the tire by said electrically conductive switching diaphragm;
a contact pin supported in said member and cooperating with the switching diaphragm;
electric oscillating circuit, the contact pin and the switching diaphragm being connected with said electric oscillating circuit; and
a detector housing in which the reference pressure chamber is thermally insulated from the wheel rim, the improvement comprising a supporting ring (22), a spacing ring (24) of insulating material, said detector housing being metallic, said member (23) having a radially projecting collar (36), the member forming reference pressure chamber (23) being axially clamped between the supporing ring (22) and the spacing ring (24) in the metallic detector housing (16) at the collar (36) thereof so that an annular gap (37) is formed between the collar (36) and an inner wall of the detector housing (16).
1 Assignment
0 Petitions
Accused Products
Abstract
A tire pressure detector for motor vehicles which is to be fastened to a wheel rim comprises a pressure switch actuated by the air pressure in the tire for monitoring the tire pressure. The pressure switch includes a reference pressure chamber with an electrically conductive switching diaphragm which closes the chamber toward the tire and which cooperates with a contact pin of the reference pressure chamber and an electric oscillating circuit connected to the latter in the detector housing. The reference pressure chamber (23) is axially clamped between a supporting ring and a spacing ring of insulating material in the metallic detector housing by a radial collar, which is formed, so that an annular gap is formed between the collar and the inner wall of the detector housing.
25 Citations
7 Claims
-
1. In a tire pressure detector for motor vehicles, comprising a pressure switch which is to be fastened to a circumference of a wheel rim and is actuated by air pressure in the tire for monitoring the tire pressure and which comprises an electrically conductive switching diaphragm;
- a member forming a reference pressure chamber closed toward the tire by said electrically conductive switching diaphragm;
a contact pin supported in said member and cooperating with the switching diaphragm;
electric oscillating circuit, the contact pin and the switching diaphragm being connected with said electric oscillating circuit; and
a detector housing in which the reference pressure chamber is thermally insulated from the wheel rim, the improvement comprising a supporting ring (22), a spacing ring (24) of insulating material, said detector housing being metallic, said member (23) having a radially projecting collar (36), the member forming reference pressure chamber (23) being axially clamped between the supporing ring (22) and the spacing ring (24) in the metallic detector housing (16) at the collar (36) thereof so that an annular gap (37) is formed between the collar (36) and an inner wall of the detector housing (16). - View Dependent Claims (2, 3, 4, 5, 6, 7)
- a member forming a reference pressure chamber closed toward the tire by said electrically conductive switching diaphragm;
Specification