High performance contra-rotating riding trowel
US5685667A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jan 16, 1996 |
| Grant date | Nov 11, 1997 |
| Priority date | — |
| Expiry date | Jan 16, 2016 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE04F21/247
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A high power, contra-rotating, twin engine riding trowel for finishing concrete comprises twin, downwardly projecting rotors that counter-rotate simultaneously. An operator sits in a seat mounted to the frame and steers the rotors with a pair of primary control levers that tilt the rotors to generate steering forces. The engines counter-rotate while establishing generally coaxial, horizontal axes of rotation. Each engine drives a rotor through a driveshaft. Both driveshafts establish generally coaxial axes of rotation that are generally parallel to the axes of rotation of the engines. Each driveshaft extends to a gearbox to transfer power to the rotor. The gearboxes are interchangeable and mounted to tiltable, pivotable steering boxes secured to the frame. A first reversing linkage couples the lever means to the arm means. A second reversing linkage means is suitably coupled to one rotor gearbox to reverse tilt it for steering. In combination, the first and second reversing linkages facilitate contra blade rotation, while maintaining stability and trowel control.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.