Article gripping apparatus

Abstract

An article gripping apparatus has a housing moved into proximity with a part to be gripped. A clamp finger is pivoted on the housing by an actuator biased by a first "stiff" spring reacting against the housing. In the clamped position, an interference wedge block is biased against the clamp finger by a second, "soft", spring reacting against the actuator to prevent the finger from opening under the influence of an external force. A piston portion of the actuator is contained in a cylinder portion of the wedge block. When pressurized fluid is ported to the cylinder cavity, the wedge block is first retracted from the clamp finger, overcoming the second, "soft", biasing spring. When the wedge block contacts a fixed shoulder in the housing, the actuator piston is then forced away from the shoulder, overcoming the first, "stiff", biasing spring, pivoting the finger to an "open" position. Release of the fluid pressure will sequentially re-bias the actuator and wedge block, pivoting the finger to a "closed" position and locking it.

Dependencies are inferred from the claim text.