Method of making and using a dynamically balanced walk behind trowel
US7172365B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 16, 2005 |
| Grant date | Feb 6, 2007 |
| Priority date | — |
| Expiry date | Sep 16, 2025 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE04F21/248
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A method is provided of making and using a walk behind rotary trowel that is “dynamically balanced” so as to minimize the forces/torque that the operator must endure to control and guide the trowel. Characteristics that are accounted for by this method include, but are not limited to, friction, engine torque, machine center of gravity, and guide handle position. As a result, dynamic balancing and consequent force/torque reduction were found to result when the machine's center of gravity was shifted substantially relative to a typical machine's center of gravity. Dynamic balancing can be achieved most practically by reversing the orientation of the engine relative to the guide handle assembly when compared to traditional walk behind rotary trowels and shifting the engine as far as practical to the right. This shifting has been found to reduce the operational forces and torque the operator must endure by at least 50% when compared to traditional machines.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.