The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Feb. 21, 1995
Filed:
Sep. 03, 1993
Erich D Fidziukiewicz, Canton, MI (US);
Connell Limited Partnership, Boston, MA (US);
Abstract
A variable force die spring is disclosed which combines high force, short axial compression distance spring assembly, such as belleville springs, and low force, high axial compression distance springs, such as coil springs, in a telescoping casing having an internal cavity. The springs are arranged within the cavity so that upon receiving a load the low force spring will compress first resulting in a large axial compression and low force resistance. The load applied to the telescoping casing will then transition from the low force spring to the high force spring. The high force spring then compresses as the load continues to be applied. In alternative embodiments, a third intermediate spring is added that compresses moderate distances under moderate pressure thereby increasing the overall axial compression and load capacity capabilities of the spring assembly. In any embodiment, the invention results in a spring that provides high forces and low axial compression when it is nearly fully compressed and low forces and high axial compression at all other stages of compression.