Photoelectric control unit with cooling chamber

• US 4,791,290 A
• Filed: 09/04/1986
• Issued: 12/13/1988
• Est. Priority Date: 10/18/1984
• Status: Expired due to Fees

• Current Assignee: Noontek Limited
• Original Assignee: Sean Noone
• Inventors: Quinlan, Michael, Noone, Sean, O'Connell, Denis
• Primary Examiner(s): NOT, DEFINED
• Assistant Examiner(s): NOT, DEFINED
• Application Number:
  US06/903,667
• Time in Patent Office: 831 Days
• Field of Search: 250/239, 250/238, 250/214 AL, 250/214 SW, 174/52 PE, 439/485, 439/487
• US Class Current: 250/239
• CPC Class Codes: F21V 23/04 the elements being switches safety devices F21V25/00
• CPC Class Codes: H05B 47/11 by determining the brightness or colour temperature of ambient light
• CPC Class Codes: Y02B 20/40 Control techniques providing energy savings, e.g. smart controller or presence detection

Abstract

A photoelectric control unit for street lighting comprises control means including a photoelectric sensor mounted on a printed circuit board for switching on a street lamp when the intensity of light falling on the sensor falls below a preset value. Electrical connection means between the P.C.B. and the lamp is provided by three connector pins which are led through a cooling chamber or stem. The pins are cranked to closely follow the contour of the chamber to dissipate heat through the chamber walls. The chamber is also filled with a high thermal conductivity potting compound for heat transfer to the walls of the chamber.

One controller for such a photoelectric control unit includes a switching means provided by a relay and a triac connected in parallel. The triac operates to prevent the relay being subjected to high voltages during switching and hence prevents pitting of the relay contacts.

Claims

1. A photo-electric control unit for a lighting circuit comprising:

control means including a photo-electric sensor for switching a lamp which is a heat source output;

electrical connection means between the control means and the output, the electrical connection means comprising connector pins;

a cooling chamber for dissipating heat generated by the output conducted by the pins, the cooling chamber comprising a base wall and a side wall upstanding from the base wall; and

the connector pins extending through the cooling chamber and being cranked intermediate the ends thereof to define a cooling chamber base wall portion and a cooling chamber side wall portion for heat transfer from the pins to the walls of the chamber.

2. A photo-electric control unit as claimed in claim 1, wherein the chamber is substantially filled with a heat conducting medium.

3. A photo-electric control unit as claimed in claim 2 in which the heat conducting medium comprises a potting compound.

4. A photo-electric control unit as claimed in claim 1 wherein the control means comprises a printed circuit board mounted in a printed circuit housing, the photo-electric sensor being mounted to the printed circuit board, the unit including a cover of translucent material through which light passes to the photo-electric sensor.

5. A photo-electric control unit as claimed in claim 1 in which the connector pins are connected to the output through a socket mounted in a socket receiving chamber connected to the cooling chamber.

6. A photo-electric control unit as claimed in claim 5 in which the socket receiving chamber includes mounting means for mounting the unit to a fixture.