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:
Dec. 10, 1996
Filed:
Dec. 19, 1994
Philip G Scherer, Fort Lauderdale, FL (US);
Mima Incorporated, Glenview, IL (US);
Abstract
A method and apparatus for applying a constant tension to a film in a wrapping machine having a film roller rotated at a variable rate by a film drawn over the film roller. The rotating film roller drives a hydraulic pump at a variable rate dependent on the rotation rate of the film roller. An oil reservoir is coupled to the hydraulic pump to form a hydraulic circuit, wherein the hydraulic pump pumps oil through the hydraulic circuit as the film roller drives the hydraulic pump. An adjustable constant pressure valve is coupled to the hydraulic circuit and maintains a constant oil pressure in the hydraulic circuit, wherein the hydraulic pump maintains a constant drag on the film roller independent of the rate at which the film roller drives the hydraulic pump, and wherein the constant drag on the film roller applies a constant tension to the film independent of the rate at which the film is drawn over the film roller.