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. 23, 1988
Filed:
May. 16, 1986
Keith A Flesher, Ronsselaer, IN (US);
Robert F Wagner, Lombard, IL (US);
Sealy, Incorporated, Chicago, IL (US);
Abstract
A spring coil has an open-ended terminal convolution which is connected to the body of the coil through a gradient arm. The gradient arm can be readily varied in length in manufacture to alter the compression and thereby the firmness of the spring coil. Offset portions are advantageously formed on terminal convolutions with a major straight part which is outwardly spaced from minor straight parts. This provides a three point engagement for the offset portion when connected to a border wire with a border wire helical spring. The offset portions of the spring coils have inside and outside shoulders adjacent their ends. The pitch of cross-helicals which join overlapped offset portions is chosen so that a cross-helical simultaneously engages the outside shoulders of one of a pair of overlapped offset portions to firmly hold the spring coil against rotation. The cross-helical preferably also catches the inside shoulders of the other overlapped portion to additionally hold that spring coil against rotation.