Broaching cutter

Patent metadata

Field	Value
Publication number	US-10369645-B2
Application number	US-201415031531-A
Country	US
Kind code	B2
Filing date	Nov 26, 2014
Priority date	Nov 29, 2013
Publication date	Aug 6, 2019
Grant date	Aug 6, 2019

Abstract

A broaching cutter includes a plurality of initial cutting blade stages for cutting formation portions to be tooth body portions in internal teeth, a plurality of intermediate cutting blade stages for cutting the formation portions to be the tooth body portions further deeply, and a plurality of final cutting blade stages for cutting formation portions to be clearance portions located deeper than the tooth body portions, the initial cutting blade stages, the intermediate cutting blade stages, and the final cutting blade stages being sequentially arranged from an upstream side in a cutting direction S. Each of a pair of distal end corners of each of cutting blades in the intermediate and final cutting blade stages has a chamfered shape larger than that of a curved shape of a pair of distal end corners of each of the cutting blades in the initial cutting blade stages.

First claim

The invention claimed is:

1. A broaching cutter for sequentially cutting a processing hole in a workpiece with a plurality of cutting blade stages provided side by side and for forming a plurality of internal teeth in the processing hole with a plurality of cutting blades arranged side by side in a circumferential direction of each of the cutting blade stages in such a manner that the internal teeth are arranged side by side in the circumferential direction, the broaching cutter comprising:
cutting blade stages configured to cut the processing hole in such a manner that cutting locations of the cutting blades become deeper stepwise in a radial direction of the processing hole in the workpiece, and are also configured to include a plurality of initial cutting blade stages configured with initial cutting blades to cut formation portions to be tooth body portions of the internal teeth, a plurality of intermediate cutting blade stages configured to cut with intermediate cutting blades, the formation portions to be the tooth body portions more deeply than the initial cutting blade stages, and a plurality of final cutting blade stages configured to cut with final cutting blades, formation portions to be clearance portions extending from the tooth body portions toward an outer periphery in the radial direction, the initial cutting blade stages, the intermediate cutting blade stages, and the final cutting blade stages being sequentially arranged side by side such that cutting is performed in an order of the initial cutting blade stages, the intermediate cutting blade stages and the final cutting blade stages,
a pair of distal end corners of each of the intermediate cutting blades in the intermediate cutting blade stages and a pair of distal end corners of each of the final cutting blades in the final cutting blade stages each have a curved shape or a chamfered shape larger than a curved shape or a chamfered shape of a pair of distal end corners of each of the initial cutting blades in the initial cutting blade stages, and
a structure of the initial cutting blade stages is configured such that a cutting depth is smaller than a cutting depth of the intermediate cutting blade stages and the final cutting blade stages.

2. The broaching cutter according to claim 1 , wherein
a guide portion configured to guide a center of the processing hole in the workpiece to a center of the broaching cutter is provided on an upstream side of the initial cutting blade stages in the cutting direction, and
the initial cutting blade stages include a cutting blade stage adjacent to the guide portion.

3. The broaching cutter according to claim 1 , wherein
the curved shape or the chamfered shape formed at the pair of distal end corners of each of the intermediate cutting blades in the intermediate cutting blade stages and the curved shape or the chamfered shape formed at the pair of distal end corners of each of the final cutting blades in the final cutting blade stages extend across an overall length of a clearance face in an axial direction of the broaching cutter.

4. The broaching cutter according to claim 2 , wherein
the curved shape or the chamfered shape formed at the pair of distal end corners of each of the intermediate cutting blades in the intermediate cutting blade stages and the curved shape or the chamfered shape formed at the pair of distal end corners of each of the final cutting blades in the final cutting blade stages extend across an overall length of a clearance face in an axial direction of the broaching cutter.

5. A broaching cutter for sequentially cutting a processing hole in a workpiece with a plurality of cutting blade stages provided side by side and for forming a plurality of internal teeth in the processing hole with a plurality of cutting blades arranged side by side in a circumferential direction of each of the cutting blade stages in such a manner that the internal teeth are arranged side by side in the circumferential direction, the broaching cutter comprising:
cutting blade stages configured to cut the processing hole in such a manner that cutting locations of the cutting blades become deeper stepwise in a radial direction of the processing hole in the workpiece, and are also configured to include a plurality of first cutting blade stages in which a pair of distal end corners of each of first cutting blades has a curved shape or a chamfered shape and a plurality of second cutting blade stages in which a pair of distal end corners of each of second cutting blades has a curved shape or a chamfered shape larger than the curved shape or the chamfered shape of the first cutting blades in the first cutting blade stages, the first cutting blade stages and the second cutting blade stages being arranged side by side in a cutting direction, and
a structure of the first cutting blade stages is configured such that a cutting depth is smaller than a cutting depth of the second cutting blade stages.

6. The broaching cutter according to claim 5 , wherein
the first cutting blade stages are disposed on an upstream side of the second cutting blade stages in the cutting direction.

7. The broaching cutter according to claim 6 , wherein
a guide portion for guiding a center of the processing hole in the workpiece to a center of the broaching cutter is provided on an upstream side of the first cutting blade stages in the cutting direction, and
the first cutting blade stages include a cutting blade stage adjacent to the guide portion.

Assignees

• Aisin Aw Co

Inventors

• Yamaya Kenichi
• Tanabe Manabu

Classifications

• B23F21/26 Primary

  Broaching tools · CPC title

• B23D43/02

  for cutting by rectilinear movement (B23D43/08 takes precedence) · CPC title