Screw compression apparatus and operation control method thereof
US6461112B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 28, 2000 |
| Grant date | Oct 8, 2002 |
| Priority date | — |
| Expiry date | Sep 28, 2020 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF04C2270/18
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
In a capacity control method for an oil-free screw compressor, when an air consumption is larger than a set amount, a rotation frequency of a motor using an inverter to drive the compressor is set to be variable. When the air consumption is a set air amount or less, the inverter is controlled in such a manner that the rotation frequency of the motor is kept at a constant value. In this state, when an operation gas pressure of the compressor reaches an upper-limit value, an air release valve is opened to discharge the operation gas to the atmosphere. Additionally, the rotation frequency of the motor is lowered to a lower-limit value. Re-compression in the compressor can be prevented, and a compressor drive torque is lowered.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.