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. 27, 1990
Filed:
Sep. 08, 1987
Edwin ver der Lely, Maasland, NL;
Cornelis J Gerardus, Rozenburg, NL;
C. van der Lely N.V., Maasland, NL;
Abstract
A mowing machine has a plurality of drive housings that are associated with the cutting units. Each unit has a carrying shaft that rotates a carrying unit which includes a carrying arm, cutting blades, and a covering disc. The carrying shaft is connected by gearing, located within the sealed drive housing, to the mowing machine's drive shaft. When the machine is in operation, the resulting friction within the drive housing causes the lubricants and air therein to expand. A channel is provided in the carrying shaft that opens at its lower end into the drive housing and at its upper end at the top of the carrying shaft under a conically configured cup spring, into a space which is not sealed from ambient pressures. The channel thus functions as a pressure vent to the otherwise sealed drive housing and permits the lubricants and air therein readily to expand and contract. The cup spring protects the channel from receiving any substantial amounts of dust or like contaminants in the air in the vicinity of the mowing machine.