Fish & Richardson P.C.
Tire pressure gauge with adjustable extension member
 A tire pressure gauge includes a tubular housing, a pressure measuring head connected to one end of the tubular housing, a pressure responsive piston provided inside the tubular housing and biased by a spring towards a pressure inlet hole of the pressure measuring head, and a plunger actuated by the piston and having a portion that extends out of the other end of the tubular housing. An adjustable extension member, which is disposed between the piston and the plunger, is connected to the plunger to adjust the length of the outwardly extending portion of the plunger or to correct the position of the graduations provided on the plunger relative to a pointing end of the tubular housing where a detected pressure is read. Preferably, the adjustable extension member is a screw member which is threadedly connected to the plunger. Adjustment or correction can be made before or after assembly by turning the screw member relative to the plunger. 
G
G01L
inventional
Tien-Tsai
Huang