Patent ID: 8167616

Claim:
A dental hand piece having at least one replaceable tip, comprising: an elongate tubular handle; a locking component securely received in an end of the elongate tubular handle, the locking component including a keyway-shaped slot; a cylindrical barrel member securely received in the end of the elongate tubular handle and disposed axially inwardly of the locking component, an interior of the cylindrical barrel member including a plurality of axially-extending notches; a spring arm member comprising a body portion having at least a pair of resilient spring arms at the end of each of which is formed a lock-stop ridge, and an axially-extending blade receiving slot therethrough; and a replaceable tip assembly secured to the cylindrical barrel member, including an instrument working tip end at a distal end of a main tip body; a shank extending from the instrument working tip end to a proximal end of the main tip body; and a flat-blade extension end provided at the proximal end of the main tip body; wherein the flat-blade extension end extends through the keyway-shaped slot provided in the locking component and through the axially-extending blade receiving slot in the spring arm member, wherein the axially-extending notches include a first lock-stop receiving notch defined on one side thereof by a gradually-sloped ramp, and a second lock-stop receiving notch defined on a side facing the first lock-stop receiving notch by a steep ramp.