Abstract: A tight end detector for tufting machines is disclosed which includes a modular switch bar assembly, a switch contact forming PC board thereon having a conductive stripe, insulating strip, a leaf-metal electrical contact member having parallel contact finger formations overlying the conductive stripe of the PC board and a thin cover layer overlying the bar, PC board, insulating strip, and electrical contact member to provide a wear surface against which yarn ends of the tufting machine may bear.

Abstract: A sliding plate valve for a gas chromatograph or the like is provided with a pneumatic actuator (22) for reciprocating a slider assembly (24) and slide pad (26) over the face surface (28) of the valve body (20). Flow passages (44) are aligned with flow openings (42) in the face surface (28) as the slide pad (26) reciprocates between purge and sample positions. The slide pad (26) is urged against the face surface (28) by force springs (60) which are movable with the reciprocating slider housing (64). The slide pad (26) and assembly (24) are maintained in alignment by the interaction of chamfered grooves (68, 70) and chamfered lip surfaces (76, 78).

Abstract: A sampling valve having a stem which reciprocates between a liquid filled chamber and a vaporizing chamber is provided with a stem seal comprised by a thermoplastic bushing fitted to the valve stem with an interference fit. The bushing is encircled by a compression band exerting a radial compressive force and is mounted in the valve body with end clearance to avoid axial compression.