Monitoring system for a predetermined field of view

• US 4,554,459 A
• Filed: 12/15/1981
• Issued: 11/19/1985
• Est. Priority Date: 01/27/1981
• Status: Expired due to Fees

• Current Assignee: Fujitec Company Limited
• Original Assignee: Fujitec Company Limited
• Inventors: Koh, Hiroshi, Tsutsumi, Suteo
• Primary Examiner(s): Westin, Edward P.
• Application Number:
  US06/331,089
• Time in Patent Office: 1,435 Days
• Field of Search: 250/550, 250/237 R, 250/237 G, 250/221, 340/555, 340/556, 340/573, 340/19 R, 350/436, 350/451, 350/452
• US Class Current: 250/550
• CPC Class Codes: G08B 19/00 Alarms responsive to two or more different undesired or abnormal conditions, e.g. burglary and fire, abnormal temperature and abnormal rate of flow

Abstract

A lift control system includes a spatial filter for producing a signal having various features, a discriminator for discriminating one or more features of the signal, and for producing a control signal when at least one of the features discriminated falls in a predetermined range, and active devices connected to the discriminator. The spatial filter is defined by a semi-spherical bowl having a plurality of openings or by a poly-face prism which is made from a plano-convex lens with its curved face so polished or cut as to have a plurality of flat faces.

Claims

1. A condition detecting device for detecting various conditions within a predetermined field angle, said condition detecting device comprising:

(a) a spatial filter element including a solid poly-facet prism member having a convex face on the side of the fields of view with a plurality of plano facts cut into said convex face for permitting trasmittal of rays therethrough from an object to define respective separate fields of view for each facet;

(b) a single converging lens element for converging the rays which have passed through the spatial filter element;

(c) sensor means for sensing said rays converged by said converging lens element and for producing a signal having various features depending on the condition of said object; and

(d) descriminating means for discriminating one or more features of said signal.

2. A condition detecting device as claimed in claim 1, wherein said sensor means is sensitive to infrared rays.

3. A condition detecting device as claimed in claim 1, wherein said sensor means has a plane face sensitive to said rays.

4. A condition detecting device as claimed in claim 1, wherein said sensor means is sensitive to infrared rays.

5. A condition detecting device as claimed in claim 4, wherein said sensor means has a plane face sensitive to said rays.

6. The invention of claim 1 wherein said converging lens element is a plano-convex lens with its convex face facing said sensor means.

7. The invention of claim 6 wherein said solid prism has a plano-convex configuration with the plano face adjacent the plano face of the plano-convex lens.

8. An improved lift control system for transporting people comprising:

(a) a cage member for supporting the people;

(b) means for supporting the cage member for movement;

(c) a spatial filter provided inside the cage member for detecting various conditions within a predetermined field angle, said spatial filter comprising;

(i) a spatial filter element defined by a solid polyfacet prism member having a convex face on the side of the fields of view with a plurality of planofacets cut into said convex face, said spatial filter element provided for filtering rays emitted or reflected from an object, with each facet defining separate fields of view;

(ii) a lens assembly for converging the rays which have passed through the spatial filter element; and

(iii) sensor means for sensing the converged and filtered rays, said spatial filter Producing a signal having various features representative of the conditions within the field angle;

(d) discriminating means for discriminating at least one feature of said signal, and for producing a control signal when at least one of said features being discriminated falls within a predetermined range; and

(e) means responsive to said control signal from said discriminating means for effecting an operation related to said lift control system.