Hydraulically controlled twin rotor riding trowel
US6053660A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 31, 1998 |
| Grant date | Apr 25, 2000 |
| Priority date | — |
| Expiry date | Mar 31, 2018 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE04F21/247
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A high performance, twin rotor riding trowel for finishing concrete and hydraulic circuitry therefor, enabling complete joystick control to the operator. The rigid trowel frame mounts two spaced-apart, downwardly-projecting, bladed rotor assemblies that frictionally engage the concrete surface. The rotor assembly blades finish the surface while supporting the trowel. The rotor assemblies are tilted with double acting, hydraulic cylinders to effectuate steering and control. Double acting hydraulic cylinders also control blade pitch. A joystick system enables the operator to hand control the trowel with minimal physical exertion. The joystick system activates electrical circuitry that fires solenoid control valves that in turn energize the various hydraulic cylinders that tilt the rotors and alter blade pitch. The hydraulic control circuitry comprises a motor driven pump delivering pressure to a flow divider circuit. A bypass-valve in line before the flow divider enables an operator to customize the trowel steering characteristics.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.