US 2004/0140629 A1 · Draw down chuck

Abstract

A drawn down chuck for gripping the inner or outer diameter of a workpiece. The chuck includes rotatable jaws disposed in a chuck body. The rotatable jaws helically and then linearly retract into the chuck body to secure workpieces having a shaft and an enlarged offset such as a hub or flange proximate to the end of the shaft. Cam assemblies interact with the jaw rods to provide the helical and linear movement. The cam assemblies include a cam groove and a cam follower, wherein the cam groove has a linear and a helical segment. The cam follower is operatively engaged on the cam groove as the jaw rod moves between the extended and retracted position so that when the jaw rod is retracted it first moves helically and then axially.

Claims18

Dependent claims

A chuck for holding a workpiece comprising:

a chuck body having a chuck axis, a bore having a bore axis angled relative to said chuck axis, and a puller cavity communicating with said bore;
a jaw rod assembly having a jaw rod disposed in said bore for movement along said bore axis between a retracted position and an extended position;
a puller disposed for movement in said puller cavity and operatively coupled to said jaw rod assembly to displace said jaw rod along said bore axis, said jaw rod being coupled to said puller for rotation relative to said puller;
and
a cam assembly having a cam follower formed in or coupled to one of said chuck body and jaw rod and a cam groove, the other of said chuck body and jaw rod defining said cam groove, said cam groove having a linear segment and a helical segment, said cam follower operatively engaging said cam groove as said jaw rod moves along said bore axis to cause said jaw rod to first move axially and then helically within said bore when said jaw rod is moved from said retracted position toward said extended position.

2 more elements

A chuck and workpiece assembly comprising:

a workpiece;
a chuck having jaws coupling said workpiece to said chuck, said chuck including:
a body having a puller cavity, a chuck axis and at least two bores each having bore axis angled relative each other, said puller cavity communicating with said bores;
at least two jaw rods disposed in said bores and movable between a retracted position and an extended position along said bore axes, said jaws facing said chuck axis when said jaw rods are in said retracted position;
a puller disposed for movement in said puller cavity, said puller being operatively coupled to said jaw rods to displace said jaw rods between said retracted position and said extended position;
at least two cam assemblies, each cam assembly including a cam follower and a cam groove, said cam follower being formed in or coupled to one of said chuck body and jaw rod and said cam groove being defined by the other of said chuck body and jaw rod, said cam groove having a linear segment and a helical segment, said cam follower operatively engaging said cam groove as said jaw rod moves from said retracted to said extended positions.

3 more elements

Dependencies are inferred from the claim text.

Draw down chuck

Life of this patent

Draw down chuck

Life of this patent

Abstract

Claims18