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:
Apr. 09, 1991
Filed:
Mar. 07, 1990
Christopher D Brandt, Peoria, IL (US);
David C Kettler, Peoria, IL (US);
Willis E Windish, Pekin, IL (US);
William W Blake, Kewanee, IL (US);
Caterpillar Inc., Peoria, IL (US);
Abstract
A particularly compact planetary gear mechanism includes an axially shiftable ring gear to provide either a direct drive mode or a speed reduction ratio mode between an input sun gear thereof and an output planet carrier thereof. In a first embodiment, the ring gear is urged in a first direction by a compressible spring apparatus to a conjoint coupled relationship with the sun gear for direct drive. In a less frequently used mode the ring gear is urged by a hydraulically actuated annular piston closely encircling it into a fixed relationship with a stationary coupling in opposition to the compressible spring apparatus. A second embodiment has no spring apparatus so that the annular piston is hydraulically biased in either axial direction for positively shifting the ring gear. A speed reduction ratio of about 3 or 4:1 is obtained in the secondary mode so that when the planetary gear mechanism is used in a vehicle a relatively low ground speed is maintainable which is especially useful for specialized attachments such as a snow blower, broom or the like. With this construction the sun gear transmits only a relatively small proportion of the total torque during the normal direct drive mode so that an economical construction is possible.