Electric blind apparatus
US4856574A · kind A · utility
Assignees
Inventors
Key dates
| Filing date | Dec 29, 1987 |
| Grant date | Aug 15, 1989 |
| Priority date | — |
| Expiry date | Dec 29, 2007 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE06B9/32
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
When a raising switch (21) or a lowering switch (23) is operated in an electric blind apparatus, an MPU (34) rotates a geared motor (4) so that a take drum (37) winds up or unwinds a lifting tape (10) to raise/lower vanes (13) of a blind. Upon rotation of the take-up drum, a photointerrupter (38) generates pulse signals and the MPU counts the pulse signals to judge a vertical position of the blind. When an opening or closing switch (24, 26) is operated, the MPU rotates the geared motor so that a ladder drum (39) is followingly rotated to wind up one of ladder cords (11) fixed to the ladder drum, thereby to adjust an open/close angle of the vanes. Following rotation of the ladder drum, a photointerrrupter (41) supplies pulse signals to the MPU, which in turn counts the pulse signals to judge the open/close angle of the vanes.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.