Michael A Rhoades

US Patent:

20160059335, Mar 3, 2016

Filed:

Nov 10, 2015

Appl. No.:

14/937508

Inventors:

Kenneth P. Griffard - Three Rivers MI, US
Carl P. McLean - Conneaut Lake PA, US
Michael Rhoades - Guys Mills PA, US

Assignee:

Meadville Forging Co. LP - Meadville PA

International Classification:

B23G 5/06

Abstract:

In a part having a surface, a bolt hole is provided extending into the part from the surface. Threads in the hole have crests with a fishmouth shape at the crests defined by a central concave portion and raised corner portions at ends of the concave portion. At least one start thread preceding the threads with the fishmouth shape crests is provided having a substantially flat crest without the fishmouth shape. A tap for manufacturing the threaded bolt hole has a first thread section and a second thread section. The second thread section has a plurality of threads for creating at least one improved start thread in the hole to be threaded, minor diameters at valleys between the threads of the second thread section being greater than minor diameters at valleys between threads of the first thread section or major diameters at crests of the threads of the second thread section being greater than major diameters at crests of the first thread section.

US Patent:

20150003936, Jan 1, 2015

Filed:

Jun 27, 2013

Appl. No.:

13/929241

Inventors:

Kenneth P. Griffard - Three Rivers MI, US
Carl P. McLean - Conneaut Lake PA, US
Michael Rhoades - Guys Mills PA, US

Assignee:

MEADVILLE FORGING CO. LP - Meadville PA

International Classification:

B23G 5/06
F16B 37/00

US Classification:

411436, 408226, 408 1 R

Abstract:

In a part having a surface, a bolt hole is provided extending into the part from the surface. Threads in the hole have crests with a fishmouth shape at the crests defined by a central concave portion and raised corner portions at ends of the concave portion. At least one start thread preceding the threads with the fishmouth shape crests is provided having a substantially flat crest without the fishmouth shape. A tap for manufacturing the threaded bolt hole has a first thread section and a second thread section. The second thread section has a plurality of threads for creating at least one improved start thread in the hole to be threaded, minor diameters at valleys between the threads of the second thread section being greater than minor diameters at valleys between threads of the first thread section or major diameters at crests of the threads of the second thread section being greater than major diameters at crests of the first thread section.