Oil free screw compressor
US8696335B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 28, 2011 |
| Grant date | Apr 15, 2014 |
| Priority date | — |
| Expiry date | Sep 2, 2031 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF04C28/06
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
A multi-stage oil-free screw compressor includes: a suction throttle valve for controlling air intake into the compressor; a piston assembly for operating the suction throttle valve; and a structure for supplying a working pressure to the piston assembly. In order to reduce startup load at the time of startup of the compressor, the suction throttle valve is fully closed while a secondary side of a compressor body is opened to the atmosphere. When a negative pressure and the air pressure, that provide the working pressure, are used for slightly opening the suction throttle valve in order to switch the compressor to a loaded mode after a motor for driving the compressor is accelerated to its top speed, the air pressure is provided by a control pipe line that is defined by the same pipe line that forms a drain pipe line. This permits the control pipe line to be opened to the atmosphere as needed during the startup time. Thus is provided the oil-free screw compressor achieving improved startup reliability.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.