Photoelectric icing detector

• US 4,782,331 A
• Filed: 06/10/1987
• Issued: 11/01/1988
• Est. Priority Date: 06/10/1986
• Status: Expired due to Fees

• Current Assignee: US Philips Corporation (Koninklijke Philips N.V.)
• Original Assignee: US Philips Corporation (Koninklijke Philips N.V.)
• Inventors: Martens, Gerd H.
• Primary Examiner(s): Swann, III, Glen R.
• Application Number:
  US07/061,231
• Time in Patent Office: 510 Days
• Field of Search: 340/583, 340/580
• US Class Current: 340/583
• CPC Class Codes: B64D 15/20 Means for detecting icing or initiating de-icing
• CPC Class Codes: F25B 2700/111 using an emitter and receiver, e.g. sensing by emitting light or other radiation and receiving reflection by a sensor
• CPC Class Codes: F25D 21/02 Detecting the presence of frost or condensate
• CPC Class Codes: G08B 19/02 Alarm responsive to formation or anticipated formation of ice

Abstract

An arrangement for the detection of icing on the surface of an object includes an optical conductor in which the radiation from a source strikes at least one plane of the conductor, which is located in the area of the surface to be tested and which is accessible from outside the object, and a detector which receive the radiation coming from this conductor plane and converts it into an electrical signal. An evaluation device compares the signal which a threshold value and, depending on the result of the comparison, generates an alarm signal.

Claims

1. An arrangement for the detection of icing on the surface of an object comprising

a source for generating a parallel beam of optical radiation,

an optical conductor in the shape of a prism and having two faces which project above the surface on which icing is to be detected, said radiation beam striking one of said faces from inside the conductor,

a detector which receives radiation reflected from both of said faces and converts it into an electrical signal,

an evaluation device which compares the signal with a threshold value and, depending on the result of the comparison, generates an alarm signal.

2. An arrangement as in claim 1 wherein the prism forms an angle of about 90°

between the faces and the beam is essentially parallel to the angle bisector.

3. An arrangement as in claim 1 wherein the prism is in the shape of a cone.

4. An arrangement as in claim 1 wherein the source of optical radiation and the detector are connected to the optical conductor via optical fibers.

5. An arrangement as in claim 1 wherein the optical radiation is infrared radiation close to the visible range.