| 摘要 |
An apparatus (12) detects an opening in a fluid flow passageway (24) such as occurs when a resistance welding cap (18, 20) which is cooled by the fluid flow becomes accidentally detached from a welding machine (14). Upon detection of an opening, an air-actuated pinch lever (88, 92) is activated to quickly pinch shut flexible fluid inlet and outlet hoses (80, 84) and thereby shut off the fluid flow. Another fluid flow sensor or control device (236) fits into a recess (232a) in a fluid flow manifold (232). The recess (232a) has a rectangular, V-shaped or circular cross section, and the device (236) has a shape which is conjugate to the cross section of the recess (232a). The device (236) is formed with a fluid flow passageway (236a) therethrough having an inlet (236b) and an outlet (236c) which sealingly communicate with an inlet (232f) and an outlet (232g) of the manifold (232) respectively. The manifold (232) and device (236) are configured such that flow through the inlet and outlet ports (232f, 232g) and the passageway (236a) is substantially in a straight line, thereby eliminating pressure drops that would otherwise be created by bends in the flow path. |
