Bacon & Thomas
Compact pressure gauge
 A compact pressure gauge includes an outer housing, a rotating shaft journalled on the outer housing, and a tubular member fixed on the outer housing and extending through the outer housing. A pinion and an indicator are secured to the rotating shaft. A movable seal member is disposed sealingly within the tubular member for being forced by air pressure in an article to be measured and is biased by a compression spring, which has intimately coiled turns for being sleeved on a stepped spring seat, to move outwardly. A U-shaped rack member has parallel first and second arms. The first arm extends into the tubular member and is connected to the seal member for being impelled by the seal member. The second arm is provided with a rack meshing with the pinion. In use, the seal member will be pressed to move the rack member and in turn will rotate the rotating shaft by interaction between the pinion and the rack. 
G
G01L
inventional
Tien-Tsai
Huang