VENETIAN BLIND WITH AUTOMATIC CONTROL OF ROOM BRIGHTNESS

• US 3,646,985 A
• Filed: 04/13/1970
• Issued: 03/07/1972
• Est. Priority Date: 04/13/1970
• Status: Expired due to Term

• Current Assignee: Horst Klann
• Original Assignee: Horst Klann
• Inventors: Klann, Horst
• Primary Examiner(s): Caun, Peter M.
• Application Number:
  US05/027,664
• Time in Patent Office: 694 Days
• Field of Search: 160/1,5,168-178
• US Class Current: 160/168.10R
• CPC Class Codes: E06B 9/32 Operating, guiding, or securing devices therefor operation of tilting bars E06B9/307

Abstract

A venetian blind is provided with an electric motor to run the blind up and down. The motor also tips the slats one way or the other automatically to control the amount of light admitted to a room as detected by a control circuit having a photosensitive device in the room.

Claims

1. In combination a venetian blind and control circuit for tilting a plurality of slats of said venetian blind to a desired position so that the venetian blind transmits a predetermined intensity of light, said control circuit comprising reversible motor means operatively connected to said slats for tilting said slats in one direction when said motor means is forwardly energized and for tilting said slats in an opposite direction when said motor means is reversely energized;

power supply means;

a light sensitive device connected to said power supply means and responsive to the intensity of light transmitted by said venetian blind for emitting an electrical signal at its output which has a value proportional to the light intensity illuminated thereon; and

switching circuit means electrically connected to the output of said light sensitive device, operatively connected to said reversible motor means and responsive to the value of said signal for providing forward and reverse energization to said motor means for tilting said slats and for deenergizing said motor means when said slats reach said desired position, wherein said switching circuit means includes a first transistor electrically connected to the output of said light sensitive device and responsive to the value of said signal for emitting a second signal having a value proportional to the value of said first signal, a second transistor connected to the output of said first transistor and responsive to said second signal for energizing said motor means in one direction in the event the value of said second signal exceeds a predetermined value, and a third transistor connected to the output of said first tRansistor and responsive to said second signal for energizing said motor in an opposite direction in the event the value of said second signal goes below said predetermined value.

2. A control circuit according to claim 1 including relay means electrically interconnecting said second and third transistors and said motor means for energizing said motor means in one direction and in said opposite direction depending upon the value of said second signal.