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, 2002
Filed:
Jul. 13, 1999
Peter J. Smith, Hartford, WI (US);
Hassan Karbassi, Hartland, WI (US);
Wacker Corporation, Menomone Falls, WI (US);
Abstract
A self-propelled concrete finishing trowel has a power steering control system that steers the machine by tilting the driven shaft(s) of the rotor assembly or assemblies of the machine without requiring the imposition of fatiguing actuating forces by the machine's operator. The steering control system includes at least one electric actuator, such as a ball screw actuator, coupled to each rotor assembly of the machine and controlled by an operator-manipulated controller. The controller preferably includes at least one, and possibly two, joysticks that can be manipulated by the operator to steer the machine in the direction of joystick motion and preferably at a speed that is proportional to the magnitude of joystick movement. In the typical case in which the machine is steered by pivoting a gearbox of at least one rotor assembly about two axes, a separate actuator is provided for each axis of gearbox pivoting. The resultant machine is easy to operate, lightweight, and exhibits little risk of high-pressure fluid spills.