Abstract: A pneumatic ‘Pinch Valve’ control assembly for regulating stopping and/or starting the supply of gasses, air and/or water to a tool, or any type of Dental or Laboratory handpiece in response to it's shaft entering and encircling the inner circumference inside a hanger or holder in which it is removably stored. The assembly comprises of a standard handpiece holder FIG. No. 1a normally referred to as a Universal holder, front section modified for this application and attached to a Back Plate or adapter through which channels are bored to allow flexible air tubing vinyl or other material passage in a horizontal or vertical manner.

Abstract: A fluidic control assembly for controlling the supply of drive air and/or water to a tool such as a dental handpiece in response to its presence or absence in a hanger in which it is removably stored. The assembly comprises a primary fluidic control and a secondary control, with the primary fluidic control having a control valve which directs the flow of drive air from a source of supply through a primary chamber to a main outlet coupled to the handpiece. The control valve extends into a secondary chamber having means for operating the control valve in response to a predetermined pressure level in the secondary chamber. The secondary chamber communicates with the secondary control, which is integrated in the hanger for sensing the presence or absence of the tool in the hanger. The secondary control causes a build-up of pressure in the secondary chamber when the tool is absent from the hanger and causes the pressure in the secondary chamber to drop below the predetermined level when the tool is present.

Abstract: In the present apparatus, the removal of a dental handpiece from its holder opens a pilot-operated valve for supplying air or both air and water to the handpiece in conjunction with the usual foot pedal-operated valve.Preferably, the holder has aligned, narrow air passages on opposite sides of a recess which receives the handpiece, and the handpiece blocks these passages when it is in the holder. Upon removal of the handpiece, the flow of air from one of these passages across the recess and into the other passage supplies the pilot pressure for opening the pilot-operated valve. The pilot-operated valve may be separate from the holder or contained within it.In another embodiment, the holder has a reciprocable valve member controlling the application of pilot pressure to the pilot-operated valve. This valve member is depressed to a closed position by the handpiece when the latter is in the holder and is biased to an open position when the handpiece is removed from the holder.