Abstract: A counter-balanced parallel arm assembly for supporting a control unit for dental handpieces, such as high speed air drills, and other air driven or electrically energized dental instruments which are removably mounted on the control unit, or for supporting other medical, electrical, electronic, or other units. The assembly includes an upright standard, a first arm mounted on the standard to be rotatable about a vertical axis, and a second arm coupled to the end of the first arm and rotatable about both vertical and horizontal axes. The supported unit is suspended from the end of the second arm by a post, and it is rotatable about the longitudinal axis of the post. The post is pivotally coupled to the end of the second arm to be rotatable about a horizontal axis. The supported unit may be set to any desired vertical and horizontal position to locate it for convenient access by the operator.

Abstract: A syringe is provided which is particularly useful in dental work, but which has general utility. The syringe includes pinch valves, and it is constructed to be simple and inexpensive, requiring a minimum of components, and yet to be highly reliable. The syringe is capable of emitting, for example, a stream of air and water, or other fluids or particulate matter, each of which is independently controlled, and neither of which has any tendency to be emitted when only the other is required.

Abstract: A control and selector unit for a dental handpiece is provided of the high pressure air driven type. The control and selector unit includes a bracket for supporting a handpiece, and a resilient metal strip having a free end extending into the bracket. The other end of the resilient strip is supported on the base of the control unit, and the strip acts as a pinch valve for a tube carrying high pressure drive air to the handpiece. The pinch valve releases the tube when the handpiece is removed from the bracket so as to cause the handpiece to be activated. The control unit may also include additional resilient strip pinch valve controls for controlling the supply of coolant air, or other gases, and water to the handpiece when the handpiece is removed from the bracket.

Abstract: A control unit is provided for a plurality of dental handpieces of the electrically energized type, which includes individual arms for supporting the handpieces, and which selectively directs the flow of pressurized air to the handpieces, so that high pressure driving air may be supplied to a selected handpiece as it is removed from its supporting arm. The air pressure is controlled by a common controller which may be of the usual foot operated type in general use in most dental offices, so that the speed of the selected handpiece may be controlled. The unit includes a pressure-sensitive electrical impedance of each of the electrical handpieces which responds to the pressurized air from the controller as the corresponding electrical handpiece is selected to control the flow of electrical energy to the selected handpiece.