R lamp having an improved neck section for increasing the useful light output

• US 4,536,834 A
• Filed: 05/22/1984
• Issued: 08/20/1985
• Est. Priority Date: 05/22/1984
• Status: Expired due to Fees

• Current Assignee: General Electric Company
• Original Assignee: General Electric Company
• Inventors: Bloom, Daniel M., Sands, Robert W.
• Primary Examiner(s): Nelson, Peter A.
• Application Number:
  US06/612,778
• Time in Patent Office: 455 Days
• Field of Search: 362/297, 362/303, 362/310, 362/311, 362/346, 362/347, 313/113, 313/114, 313/315, 313/318, 313/317, 313/479, 313/578-580
• US Class Current: 362/303
• CPC Class Codes: H01K 1/325 Reflecting coating

Abstract

A reflector (R) having an improved neck section that increases the useful light output of the lamp is disclosed. The reflector lamp comprises a concave reflector having a primary reflective surface with a parabolic shape, one or more intermediate reflective surfaces with a parabolic shape substantially confocal with the primary reflective surface, and an improved neck section comprising a reducing section, a first substantially straight cylindrical section, an expanding section and a second substantially straight cylindrical section.

Claims

1. A reflector lamp comprising an electrically conductive base, a concave reflector, and a finite light source having its geometric center located approximately at the focal point of the concave reflector and rigidly affixed to an electrically insulative stem;

said concave reflector comprising;

(a) a primary reflective section having a parabolic shape and a focal point;

(b) one or more intermediate reflective section each having a parabolic shape substantially confocal with said primary reflective section and each respectively joined by one or more transitional sections and;

(c) a neck section effective in advantageously reflecting light rays impinging onto its surface back into the useful beam pattern of the reflector lamp and comprising;

(c_i) a reducing section;

(c_ii) a first substantially straight cylindrical section;

(c_iii) an expanding section, and;

(c_iiii) a second substantially straight cylindrical section for mating with the electrically conductive base.

2. A reflector lamp according to claim 1 further comprising:

a light reflective heat shield having a reflective surface that is positioned under such light source and mounted onto said electrically insulative stem.

3. A reflective lamp according to claim 2 wherein said light reflective heat shield is of a parabolic shape.

4. A reflective lamp according to claim 2 wherein said light reflective heat shield is separated from the inner walls of said first substantially straight cylindrical section by a distance in the range of about 1.5 mm to about 4.7 mm.

5. A reflector lamp according to claim 2 wherein said light reflective heat shield is separated from the junction of said first substantially straight cylindrical section and said expanding section by a distance in the range of about 1.57 mm to about 12.7 mm.

6. A reflector lamp according to claim 1 wherein one or more of said transitional sections have a radius of curvature in the range of about 1.0 mm to about 3.0 mm.

7. A reflector lamp according to claim 1 wherein said neck section comprises:

said reducing section has a radius of a curvature in the range of about 1.4 mm to about 4.0 mm;

said first substantially straight cylindrical section has an inner diameter in the range of about 27 mm to about 31 mm and a length of about 6.35 mm to about 25.4 mm;

said second substantially straight cylindrical section has an inner diameter in the range of about 35.6 mm to about 38.0 mm and a length in the range of about 25.6 mm to about 31 mm, and;

said expanding section has a minimum inner diameter in the range of said first substantially straight cylindrical section and a maximum inner diameter in the range of said second substantially straight cylindrical section.

8. A reflector lamp according to claim 1 wherein;

said expanding and said second substantially straight cylindrical sections are translucent, and;

said primary section, said one or more intermediate sections, said one or more transitional sections, and reducing section, and said first cylindrical section are coated with a reflective material.

9. A reflector lamp according to claim 1 wherein said light source is axially aligned parallel to the lamp axis.

10. A reflector lamp according to claim 1 wherein said light source is aligned perpendicular to the lamp axis.

11. A reflector lamp according to claim 1 wherein said light source comprises a tungsten filament.

12. A reflector lamp according to claim 1 wherein said light source comprises a halogen regenerative cycle lamp.

13. A reflector lamp according to claim 1 wherein said light source comprises an arc discharge lamp.