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:
Jul. 10, 1990
Filed:
Feb. 15, 1989
Winfried Walzer, Elchingen, DE;
Thomas Sommer, Ulm-Jungingen, DE;
Hydromatik GmbH, Elchingen, DE;
Abstract
A drive system for machines and vehicles with a hydraulic and mechanical transmission arranged thereafter having a driving motor and a control member which can continuously vary the speed of the motor. A hydraulic converter also controlled by a control member dependent upon the speed of the driving motor and the running pressure of the motor is also provided, in which a transmission arranged after the converter and a shifting mechanism is connected to an electronic control circuit so that an operating element for shifting gears of the transmission may achieve a comfortable shifting behavior for the transmission. Shifting from a high gear to a low gear will occur only under the following conditions: (a) before shifting, the output speed of the hydraulic converter is below a certain predetermined value, and (b) before shifting, the transmission ratio of the converter reaches a specific minimum value caused by the working pressure of the motor.