US3624383A

US3624383A - Illuminated inspection apparatus

Info

Publication number: US3624383A
Application number: US872878A
Authority: US
Inventors: Robert E Maltby Jr; Albert W Olson
Original assignee: Libbey Owens Ford Co
Current assignee: Pilkington North America Inc
Priority date: 1969-10-31
Filing date: 1969-10-31
Publication date: 1971-11-30
Anticipated expiration: 1988-11-30

Abstract

Method of and apparatus for inspecting articles while they are being treated in a heated furnace and conveyed through a brightly illuminated area. The viewing area of the apparatus is arranged in angular relation to the light sources to afford protection for an observer from the glare of the light sources while permitting satisfactory examination of an article passing through the area.

Description

United States Patent Inventors Robert E. Maltby, Jr.

Perrysburg; Albert W. Olson, Toledo, both of Ohio Appl. No, 872,878 Filed Oct. 31, 1969 Patented Nov. 30, 1971 Assignee Libbey-Owens-Ford Company Toledo, Ohio ILLUMINATED INSPECTION APPARATUS 4 Claims, 8 Drawing Figs.

US. Cl 240/2.l8, 126/200, 240/2 AD, 240/2 W Int. Cl F2ls 1/00, F 2 1 v 3 3/00 Field of Search 240/218, 2

AD, 2 W, 2 AT; 350/319; 126/200 [56] References Cited UNITED STATES PATENTS 1,887,654 11/1932 Mahon 126/200 UX 2,368,350 1/1945 Ellison 240/218 2,733,706 2/1956 Feder 1. 126/200 2,747,568 5/1956 Dupler 126/200 X 3,192,575 7/1965 Rosenau, Jr, et a1 126/200 X 3,316,468 4/1967 Hanks 1. 126/200 X Primary ExaminerLouis R. Prince Assistant Examiner-Daniel M. Yasich Alt0rney-Collins & Oberlin ABSTRACT: Method of and apparatus for inspecting articles while they are being treated in a heated furnace and conveyed through a brightly illuminated area. The viewing area of the apparatus is arranged in angular relation to the light sources to afford protection for an observer from the glare of the light sources while permitting satisfactory examination of an article passing through the area.

PATENTED urn/30 |97| SHEET 1 BF 4 SPECIFICATION The inspection apparatus of this invention is made up of observation units in one wall of a heated furnace and similarly formed units in an opposite wall of the furnace that are equipped with sources of light. More particularly, the invention provides an inspection apparatus wherein units having transparent areas are arranged in one wall of a furnace in angular relation to units having sources of light in an opposite wall.

An important object of the invention is to protect an observer from objectionable glare from the light source while affording satisfactory and complete inspection of articles being treated within a furnace.

Another object of the invention is to provide an apparatus of the above character in which the units for the purpose of observation and for providing a source of light are constructed to prevent loss of heat from the furnace.

Another object of the invention is to provide novel mounting means for the observation units and light units in the walls of a furnace whereby to enable installation and removal in a convenient manner. I

Other objects and advantages of the invention will become more apparent during the course of the following description when read in connection with the accompanying drawings.

In the drawings, wherein like numerals are employed to designate like parts throughout the same:

FIG. 1 is a fragmentary side elevation of a furnace provided with an inspection apparatus, constructed in accordance with the invention;

FIG. 2 is a similar view from the opposite side of the furnace;

FIG. 3 is a horizontal sectional view taken on the plane of line 3-3 of FIGQl;

FIG. 4 is an enlarged transverse, vertical sectional view taken on the plane ofline 4-4 of FIG. 1;

FIG. 5 is a fragmentary horizontal sectional view taken on the plane of line 5-5 of FIG. 1;

FIG. 6 is a perspective view, partly in section, of the framing members for glass panels;

FIG. 7 is a fragmentary enlarged transverse, vertical sectional view taken on the plane of line 7-7 of FIG. 3; and

FIG. 8 is a horizontal sectional view taken on the plane of line 8-8 of FIG. 7.

DETAILED DESCRIPTION OF THE INVENTION With reference now to FIG. 1 of the drawings, there is shown the installed assembly of a plurality of observation units, generally designated by the numeral 10, that are mounted within a frame 11 located in the wall 12 ofa furnace 13. As seen in FIG. 3, the observation units are arranged in angular relation to like units 15 similarly mounted in a frame 16 that is located in the oppositely disposed wall 17 of the furnace 13. A plurality of horizontally disposed, operably-driven conveyor rolls 20 are arranged, in parallelism, between the

walls

12 and 17 and have shafts 21 journaled in bearings 22 supported on a framework 23 adjacent the furnace wall 17. Additionally, the units 15 are each provided with a lamp housing 25 within which is contained a light source for the observing and carrying out inspection operations.

Generally speaking, the

units

10 and 15 are substantially the same in construction and are mounted in the same manner within their

respective frames

11 and 16. In FIGS. 4 and 5, the structure of frame 11, as herein to be described, is duplicated in the structure of frame 16. Thus, the frame 11 is formed with upper, lower and oppositely disposed

sidewalls

30, 31 and 32, respectively, that are generally of a Z-shape cross section and have an integral mounting flange 33. According to the number of units to be mounted in the frame, such as four in FIG. 1, webs 35 having the same Z-shape wall structure are located in spaced relation between the upper wall and lower wall 31 and integrally formed with the sidewalls 32. The frame 11 is bodily received within the walls 36 of an aperture or viewing opening 37 in the furnace wall 12. Preferably, a layer of insulation material 38, such as asbestos, is located between the frame, the walls 36 and the outer surface panel 40 of the wall 12. As shown in detail in FIG. 4, and also as in FIG, 1, latch plates 45, supported on fixed threaded studs 46, are adapted to be urged by the nuts 47 against the flange 33 of the frame 11 to secure the same within the opening 37. This is the same at the top, bottom and sides of the frame 11 as well as of the frame 16, With regard to frame 16 as in FIG. 3, it will be seen to be located within the walls 50 of an opening 51 that is pro vided in the wall 17 in angular relation to the longitudinal plane thereof.

The body of each unit 10, and/or 15, is formed with upper, lower and

sidewalls

55, 56 and 57, respectively, that are of a Z-shape cross section, and a mounting flange 58. A supporting frame 60 for a plurality of glass panes is received within the upper, lower and sidewalls of the unit. This supporting frame 60 is formed by the assembly of bars 61 having grooves 62, arranged in parallel with one another, and mitered end surfaces 63 (FIG, 6). The bars are preferably of a material which has good heat-resistant properties to reduce conduction of heat to the glass panes and also provide a normally long anticipated length of service.

The glass panes, indicated at 65, 66 and 67, are received in the grooves 62 as each bar is fitted around a marginal edge of the panes. When the supporting frame 60 is located in the body of the

unit

10 or 15, it is secured therein by a retaining member 68 that is fixed by screws 69 against the

several walls

55, 56 and 57. As indicated in the drawings, the frame is rather loosely received between particularly the top wall 55 and sidewalls 57 of the unit body to avoid pinching" of the edges of the glass panes as the frame is being located. This is also true with regard to the edges of the panes in the grooves 62. When a unit If) is to be mounted in the frame 11, as in FIGS. 1 and 5, a layer of asbestos 70 is placed against the frame and the unit is then secured by keeper plates 71 that are secured against the flange 58 by bolts 72 threaded into the flange 33.

It has been found practical to employ glass panes having good heat-resistant characteristics, such as glasses commercially available under the trademark Pyrex, for at least the inner pane 65 if not the medial pane 66 as well. On the other hand, the pane 66 and the pane 67 can be of regular plate glass. And, since the frame 60 can be readily removed from the body of the associated unit, the panes can be cleaned or replaced while the bars 61 are removed from their marginal edges. It is believed apparent when a unit is to be removed that a replacement unit of like size can be relatively rapidly substituted in its place to reduce heat loss from the furnace or undesired entry ofcooler air.

With reference now to FIGS. 2, 3, 7 and 8, it will be seen that each lamp housing 25 is provided with a mounting element 74 in the form of an open-ended box 75 having a planar wall 76 with integral top and bottom walls 77 and sidewalls 78. The top and bottom walls 77 have ports or holes 79 for ventilation of the box 75 while the sidewalls 78, on their outer surfaces are equipped with mounting flanges 80.

A case 82 for the light source is fixedly mounted on the outer surface of wall 76 and, like the mounting element 74, is realized in an open-ended box 83 having a planar wall 84 with integral top and bottom walls 85 and

sidewalls

86 and 87. The walls 85 are provided with ventilation ports 88. A closure door 90 for the case 82 is swingably mounted on the sidewall 87 by means of hinges 91 secured thereon whereby the open end of the case can be suitably closed. The door 90 is held by a latch arrangement including an eyebolt 92, swingably mounted by a bracket 93 on the sidewall 86, a keeper plate 94 on the door 90 and a wingnut 95.

The case 82 is secured by its wall 84 to the wall 76 of the box 75 by means of threaded studs 96, fixed in the wall 76, passing through aligned openings in the wall 84 and with nuts 97 thereby securing this mounted relation. The

walls

76 and 84 are provided with registering openings to afford a passageway 98 through which the rays from the light source 100 will be projected.

For the purposes of this invention, an electric lamp is employed that is adapted to function satisfactorily in relatively high ambient temperatures. For this reason, the light source 100 is an iodine quartz lamp, such as can be obtained commercially by the listing "Sylvania SOO/Q/CL Single-Ended Iodine Quartz Lamp. This lamp is received in a socket [01 supported by means of a bracket 102 on the wall 84.

The unit 15 with the lamp housing 25 is mounted and secured in the frame 16 by means of the flanges 80 on the sidewalls 78 of the mounting element 74. As the unit is being located within the frame, a layer of insulation material 106, such as asbestos, is placed between the flange 58 and the frame. Clamping plates 107 on bolts 108, threaded into the flanges of the frame 16, are placed against the flanges or brackets 80 to firmly maintain the unit in position as the bolts are turned into the flanges 33.

MODE OF OPERATION With particular reference to FIG. 3, it will be noted that the provision of several panes of glass in a supporting frame of heat-resistant material provides a relatively large area for the observation of articles being treated within a heated furnace without loss of heat or entry of cooler air. Such protection from transmission of heat through the units 10, through which the articles can be seen, reduces any discomfort to a person making an inspection. This same manner of protection also serves to substantially lower any damaging effect on the sources of light in the housings 25 on the units 15. The axial plane T of the opening 37 in the wall 12 of the furnace is located in substantially transverse relation to the longitudinal axial plane L of the furnace. On the other hand, the axial plane A of the opening 51 in the wall 17 is arranged in predetermined angle to the axial plane L such that the beams of light from the lamps 100 will be more or less fully directed toward the inner surface of the wall 12 and not directly toward the opening 37. These beams of light in consequence "provide a wide, highly illuminated field through which an article, designated by the numeral 110, will be conveyed.

This manner of illumination has been employed to good advantage in the inspection of transparent articles 110, such as sheets or plates of glass and articles produced therefrom. Usually a sheet of glass is supported in a vertical plane on a rack or similar form of carrier 111 by which it is conveyed on the rolls 20 through the furnace. Such inspection is made by an observer whose line of vision is preferably along a plane indicated by the letter V. When so located, the observer will have substantially complete opportunity to inspect the transunits 15 is such that the vision of an observer will not be impaired by the brilliance of the light beams while he is viewing an article along a plane, such as the plane V, which is an angle of convenience to both the plane T of the opening 37 and the plane A of the opening 51.

It is also realized the manner of installing the

units

10 and 15 into their

respective frames

11 and 16 provides for rapid securement as well as for easy removal for cleaning and/or replacement of the glass panes when the bars 61 of the supporting frame are separated therefrom.

We claim:

1. In apparatus for visually inspecting transparent articles being conveyed along a predetermined path within an enclosed chamber having oppositely disposed sidewalls, the improvement comprising a first opening in one of said sidewalls, a tubular extension projecting outwardly from said opening in a direction inclined to said path, a glazing frame at the outer end of said tubular extension, a transparent glazing sheet in said glazing frame, means directing light through said transparent sheet and along sard tubular extension to illuminate said articles, a second opening in the other of said sidewalls, a glazing frame in said'second opening, and a transparent glaz ing sheet in said last-named glazing frame permitting observation of illuminated portions of said transparent articles along a sight line at an angle to and intersecting both said path of movement and said light path.

2. Apparatus for visually inspecting articles being conveyed along a predetermined path as claimed in claim I, in which each of said glazing frames includes a plurality of said transparent glazing sheets in spaced face-to-face relation, and said light-directing means includes a light source within-a case carried by said tubular extension outwardly of said transparent glazing sheets.

3. Apparatus for visually inspecting articles being conveyed along a predetermined path as claimed in claim l, including a plurality of said first openings, tubular extensions, glazing frames and light-directing means in superimposed relation in said one wall, and a plurality of corresponding second openings and glazing frames in superimposed relation in said other wall permitting observation over a large area of said articles moving along said path.

4. Apparatus as defined in claim 1, in which said glazing frames are generally Z-shaped in cross section, and each of said frames is glazed with a plurality of sheets of glass to close said wall openings and insulate said light source and said observation point from the interior of said chamber while permitting the passage of light.

Claims

1. In apparatus for visually inspecting transparent articles being conveyed along a predetermined path within an enclosed chamber having oppositely disposed sidewalls, the improvement comprising a first opening in one of said sidewalls, a tubular extension projecting outwardly from said opening in a direction inclined to said path, a glazing frame at the outer end of said tubular extension, a transparent glazing sheet in said glazing frame, means directing light through said transparent sheet and along said tubular extension to illuminate said articles, a second opening in the other of said sidewalls, a glazing frame in said second opening, and a transparent glazing sheet in said last-named glazing frame permitting observation of illuminated portions of said transparent articles along a sight line at an angle to and intersecting both said path of movement and said light path.

2. Apparatus for visually inspecting articles being conveyed along a predetermined path as claimed in claim 1, in which each of said glazing frames includes a plurality of said transparent glazing sheets in spaced face-to-face relation, and said light-directing means includes a light source within a case carried by said tubular extension outwardly of said transparent glazing sheets.