US 5,352,068 A · Broach apparatus

Abstract

A shell-type internal broach assembly including a number of annular insert mounting shells interleaved with a number of annular spacers, and mounted on an arbor. The annular insert mounting shells are sufficiently short so as to permit the use of travelling-wire EDM manufacturing methods. As a result, inserts can be precisely and accurately located and secured to the annular insert mounting shells, thereby presenting a highly repeatable broaching configuration to a workpiece. The precision by which the annular insert mounting shells are formed also promotes concentricity of the annular insert mounting shells, which further promotes the accurate and precise placement of the inserts relative to the longitudinal axis of the arbor. The use of the annular spacers also effectively reduces the cost of the internal broach assembly, in that the simple cylindrical outer surface of the annular spacers are less expensive to manufacture than the complex surface features necessary to accurately receive the inserts on the periphery of the annular insert mounting shells. The number and length of the annular spacers used can be varied in accordance with the strength required by the inserts to resist deformation by the cutting forces.

Claims18

Dependent claims

A broach apparatus comprising:

an arbor;
a plurality of annular members disposed on said arbor, each of said plurality of annular members having a plurality of longitudinal slots located on its outer periphery, said plurality of annular members being aligned on said arbor so as to align each of said slots of said plurality of longitudinal slots and thereby define a plurality of segmented elongated slots extending substantially longitudinally along the outer periphery of said plurality of annular members disposed on said arbor;
a plurality of annular spacers disposed on said arbor, at least one of said plurality of annular spacers being disposed between at least one adjacent pair of said plurality of annular members;
at least one cutting insert mounted in each of said plurality of longitudinal slots located in the outer periphery of said plurality of annular members;
and
means disposed on said arbor for retaining said plurality of annular members and said plurality of annular spacers concentrically positioned relative to each other on said arbor.

3 more elements

An insert mounting assembly for an internal broach apparatus having an arbor, said arbor having an abutment, a threaded portion spaced apart from said abutment, and a cylindrical portion intermediate said abutment and said threaded portion, said internal broach apparatus supporting a plurality of inserts and including a threaded member mounted to said threaded portion, said insert mounting assembly comprising:

a plurality of annular members disposed on said cylindrical portion of said arbor, each of said plurality of annular members having at least one slot formed on its periphery, said plurality of annular members being aligned on said arbor so as to align said at least one slot of each of said plurality of annular members so as to define at least one segmented elongate slot extending substantially longitudinally along said arbor, said at least one segmented elongate slot receiving at least one of said plurality of inserts;
means for securing said at least one of said plurality of inserts in said at least one segmented elongate slot;
and
a plurality of annular spacers disposed on said cylindrical portion of said arbor, at least one of said plurality of annular spacers being disposed between at least one adjacent pair of said plurality of annular members.

1 more element

Dependencies are inferred from the claim text.

Broach apparatus

Life of this patent

Broach apparatus

Life of this patent

Abstract

Claims18