Light barrier apparatus

• US 3,870,878 A
• Filed: 05/16/1973
• Issued: 03/11/1975
• Est. Priority Date: 05/16/1973
• Status: Expired due to Term

• Current Assignee: Arthur A.W. Walter, Erwin Langenbach
• Original Assignee: Arthur A.W. Walter, Erwin Langenbach
• Inventors: Langenbach, Erwin, Walter, Arthur A. W.
• Primary Examiner(s): Lawrence, James W.
• Assistant Examiner(s): Nelms, D. C.
• Application Number:
  US05/360,966
• Time in Patent Office: 664 Days
• Field of Search: 250/239,552 339/176L,59L,6R 240/2R,8.16
• US Class Current: 250/239
• CPC Class Codes: G01V 8/12 using one transmitter and one receiver

Abstract

A light barrier system including a light source in a first enclosure and a photosensitive element in a second enclosure. The enclosures are of like structure and each defines a chamber which communicates optically with its exterior. Each enclosure has a housing with a cylindrical bore through it, and a sleeve slidable into the bore. The sleeve has a flange about one end which is engageable with a step on the inside of the bore. The light source and photosensitive element are each mounted on a sleeve in a different enclosure at the sleeve end opposite the flange. The ends of the bores to which the light source and photosensitive element are exposed are each covered with a lens. Each sleeve has an aperture in its flanged end through which an electrical conduit carries leads to the light source and photosensitive element. The sleeves are sealable in the housings by packing material adherent to the electrical conduit and a sealing ring, all of which are held in place by beading around the end of the bore.

Claims

1. a sleeve slidable into said bore and having first and second ends,

2. an active optical element comprising one of a lamp and a photocell mounted on said sleeve,

3. The enclosure of claim 2, further comprising:

a. a sealing ring disposed about the exterior of said electrical connector, said sealing ring being located adjacent said packing material on the opposite side of said packing material from said flanged portion of said sleeve when said connector is inserted into said aperture, and b. a first bead portion extending about said first end of said housing for at least partially enclosing and holding in place said sealing ring in order to maintain said electrical connector, said sleeve and said packing material rigidly disposed with respect to said housing when said sleeve is slid into said bore.

4. said sleeve having a flange around the periphery of its first end, said flange being engageable with said first step for establishing a press fit relation of said sleeve in said bore defining the maximum extension of said sleeve into said bore, at which maximum extension said optical active element is located substantially at the focal point of said lens.

5. The enclosure of claim 1, wherein said bore and said sleeve possess circular cross-sections.

6. The enclosure of claim 1, wherein:

said active optical element in said sleeve is mounted in a quantity of cast synthetic resin extending about said active optical element between said active optical element and said sleeve.

7. The enclosure of claim 1, wherein:

said active optical element is mounted proximate said second end Of said sleeve.

8. The enclosure of claim 4, wherein:

the thickness of said housing is less in the regions of said first and second beads than in the other regions of said housing.

9. The enclosure of claim 1, wherein said sleeve extends approximately two-thirds of the length of said bore when said sleeve is inserted into said bore so that said flange of said sleeve engages said first step of said housing.

10. The enclosure of claim 1, wherein:

a. said sleeve extends approximately to the midpoint of the length of said bore when the flange of said sleeve is engaged with said first step of said bore, and b. the inside diameter of said bore is greater in the region of said bore proximate to said second end of said housing than in the region of said bore proximate to said first end of said housing.

11. The enclosure of claim 1, wherein said active optical element is press fitted into said second end of said sleeve.

12. The enclosure of claim 1, wherein said active optical element is mounted in a threaded socket in said second end of said sleeve.

13. The enclosure of claim 1, wherein said active optical element is a gas diode light source.

14. A light barrier system comprising:

a. a light source disposed in a first assembly;

b. a photosensitive element disposed in a second assembly;

c. each of said first and second assemblies comprising;

i. a housing having an elongated bore extending therethrough, said bore having first and second ends each communicating to the exterior of said housing, and a first step peripheral to said first end of said bore, and ii. a lens sealed over said second end of said bore, and iii. an integral optical element-bearing assembly comprising;

15. A method for constructing an assembly for containing an active optical element operatively positioned therein with precision, said assembly including a housing having an elongated bore extending therethrough, and having first and second ends communicating to the exterior of said housing, said method comprising the steps of:

a. constructing an integral optical element-bearing assembly by i. mounting said active optical element proximate one end of a sleeve slidable into said bore, ii. operatively connecting an electrical connector to said active optical element, extending said electrical connector through said sleeve and through the end of said sleeve opposite said active optical element, iii. fastening said electrical connector in place in said sleeve, b. inserting said element bearing assembly into said bore to an extension at which said active optical element is located substantially at the focal point of said lens;

c. maintaining said element bearing assembly fixed at said extension in said bore, and d. covering one end of said bore with a lens.