Motor-operated valve
US4948091A · kind A · utility
Assignees
Inventors
Key dates
| Filing date | Feb 16, 1990 |
| Grant date | Aug 14, 1990 |
| Priority date | — |
| Expiry date | Feb 16, 2010 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02K7/06
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
A motor-operated valve is constructed such that a stator is provided outside of a nonmagnetic tubular member allowing flow of a fluid, with stator coils wound around a plurality of magnetic poles, and a plurality of permanent magnets are secured to an operating surface of each magnetic pole. The permanent magnets are magnetized into a number of pole-pairs arranged at a constant pitch. A rotor is rotatably supported inside of the tubular member. A number of induction teeth are formed along the circumference of the rotor at a pitch equal to the pitch of the pole-pairs of the permanent magnets, and the total number of the induction teeth is so selected that it is different from the total number of the pole-pairs of the permenant magnets by an amount equal to an even number. A mechanism including a rotation-preventing means is also provided in the rotor for converting the rotating movement of the rotor into a linear movement of a valve member.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.