Bacon & Thomas
Pressure gauge reset mechanism
 A pressure gauge reset mechanism including a cylinder having a pressure measuring head at one end, a piston forced by a first spring toward the pressure measuring head, a toothed pressure rod extending out of the cylinder, an actuating rod member having one end stopped at the piston and an opposite end fixedly connected to the toothed pressure rod, a second spring fixedly connected to the actuating rod member to push it upwards against the piston, and a pressure gauge coupled to the cylinder, the pressure gauge having an index shaft with a gear meshed with the toothed pressure rod, and a torsional spring mounted on the inside to hold down the index shaft and having one end stopped at the inside of the pressure gauge and an opposite end extending out of the pressure gauge and fixedly connected with a button, wherein the second spring member is compressed and the index shaft is turned by the toothed pressure rod to move the index of the pressure gauge when the piston is forced by the pressure being applied to the pressure measuring head to move the actuating rod member; when the button is depressed after each measurement, the torsional spring is released from the index shaft, and the second spring member is released to push the actuating rod member and the pressure rod back to their former positions, and therefore the index of the pressure gauge is returned to the zero reading position. 
G G
G01B G01L
inventional inventional
Tien-Tsai
Huang