US2469929A

US2469929A - Apparatus for coating articles

Info

Publication number: US2469929A
Application number: US503674A
Authority: US
Inventors: Osterberg Harold; Roger E Matter
Original assignee: American Optical Corp
Current assignee: American Optical Corp
Priority date: 1943-09-24
Filing date: 1943-09-24
Publication date: 1949-05-10
Anticipated expiration: 1966-05-10

Description

May 10, 1949. H. OSTERBERG ET AL APPARATUS FOR COATING ARTICLES 4 Sheets-Sheet 1 Filed Sept. 24, 1943 BYK H. OSTERBERG ET AL APPARATUS FOR COATING ARTICLES May 10, 1949.

4 Sheets-Sheet- 2 Filed Sept. 24, 1943 1 I l ||||||||||||l|| A OENEY INVENTORS HAROLD 057628526 80652 iM/ITTEE I lfllfill y 0, 1949. H. OSTERBE-RG ELIAL 2,469,9

APPARATUS FOR comma ARTICLES Filed Sept. 24, 194:. 4 Sheets-Sheet s INVENTORS #42040 057625526 ATTORNEY y 10, 1949- H. OSTERBERG ETAL 2,469,929

APPARATUS FOR COATING ARTICLES Filed Sept. 24, .1943 4 Sheets-Sheet 4 INV NIORS HAROLD 0 TEEBEEG y 2065.25 ATTEQ Aafidmvz' Patented May 10, 1949 APPAitATUS FOR COATING ARTICLES Harold Osterberg and Roger E. Matter, Buffalo, N. Y assignors, by mesne assignments, to

American Optical Company,

Southbrldge,

Mass., a voluntary association.

Application September 24, 1943, Serial No. 503,674

1 This invention relates to new and improved coating apparatus and has particular reference to new and improved apparatus for forming coatings of vaporized coating material in an evacuated chamber.

An object of the present invention is to provide new and improved means for forming durable, wear resistant coatings of vaporized coatingmaterial deposited in an evacuated chamber.

Another object of the invention is to provide new and improved means for supporting an article during the coating operation;

Another object of the invention is to provide new and improved means for coating an article in an evacuated chamber whereby the article may be observed during the coating operation;

Another object of the invention is to provide new and improved means for pivoting an object to be coated during the coating operation;

Another object of the invention is to provide new and improved means for adjustably supporting the coating material in an evacuated chamber;

Another object of the invention is to provide new and improved means for adjustably support ing an object to be coated in an evacuated chamber which'permits the coating of both surfaces of the object without disturbing the coating operation;

Another object of the invention is to provide tion taken in connection with the accompanying drawings. It will be understood that many changes may be made in the details of construction and arrangement of parts without departing from the spirit of the invention as expressed in the accompanying claims. We, therefore, do not wish to be limited to the exact details of construction and arrangement of parts shown and described as the preferred form has been given by way of illustration only.

10 Claims. (01. ill- 12.2)

Referring to the drawings:

Fig. 1 is a sectional view of an apparatus embodying the invention;

Fig. 2 is a sectional view taken on line 2-2 Fig. 1 looking in the direction of the arrows;

Fig. 3 is a sectional view taken on line 3-3 of Fig. 1 looking in the direction of the arrows;

Fig. 4 is a, sectional view taken on line 4-4 of Fig. 3 looking in the direction of the arrows;

Fig. 5 is a sectional view taken on line 5-5 of Fig. 1 looking in the direction oi the arrows;

Fig. 6 is a view similar to Fig. 3 but showing a modified form of holding apparatus;

Fig. 7 is a sectional view taken on line 1-1 of Fig. 6 looking in the direction of the arrows;

Fig. 8 is a view similar to Figs. 3 and 6 but showing a further modified form of supportingapparatus; and t Fig. 9 is a sectional view taken on line 3-9 of Fig. 8 looking in the direction of the arrows.

The apparatus of the present invention is shown adapted for the purpose of providing optical elements such as lenses, prisms or the like with reflection-reducing coatings but it will be understood that the apparatus may be adapted for other coating purposes such as the coating of mirrors or'reflectors with reflective coatings.

The apparatus embodying the invention comprises a base I adapted to support a housing member 2 to form an evacuating chamber in which the coating operation is carried out. This evacuated chamber comprises the bell jar or the like 2 which may be surrounded by the housing 3. The housing 3 is preferablya metallic housing adapted to extend around the bell jar 2 and to have openings therethrough permitting the passage of light into the interior of the evacuated chamber.

The purpose of the casing 3 is to prevent injury to the bell jar 2 and also:to prevent injury to the operator should the bell jar 2 crack or break for any reason.

The casing or housing 3 has diametrically opposed openings one of which openings contain the window 4 and the other of said openings has the housing member 5 aligned therewith which housing member contains the fluorescent lamps 6 and l for observing the work during the coating operation. The base I is provided with an opening 8 through which the evacuated chamber may be evacuated by vacuum pumps in the usual manner and overlying this opening is the sup- 3 porting structure Sfor adjustably positioning the source of coating material.

Spaced from the source of coating material is the housing member In adapted to support the articles H the surfaces of which are to be coated and which member has the hinged cover l2 as hereinafter described.

The member I0 is supported by the uprights l3 which maybe of desirednumber.

Extending through the base l are the lead members or posts M. The post is adapted to support the adjustable member l6 which supports the annular or ring shaped diaphragm member I! in alignment with the source of coating material. The ring shaped member I! is interposed between the source of vaporized coating material and the articles to be coated and acts as a vignetting member. The vignetting member is so positioned between the two that it does not cast a total shadow or any portion of the surface to be coated. On the contrary'the partial shadow which it casts brings about substantially uniform distribution of the coating material on the surfaces to be coated, even though they are not all at precisely the same distance from the source of the vaporized coating material. This vignetting member per se is described and claimed in the application of Harold Osterberg, Gilbert E. Pride, and Paul C. Heijn, Serial No. 498,972, filed August 17, 1943, which issued October 1, 1946, as Patent 2,408,529.

The posts I4 each support a lead or source of current l8 for the coil member 2|, which coil member is for the purpose of heating the coating material to vaporize said material. The coating'material is positioned within the crucible which crucible is surrounded by the shield member l9 to prevent loss of heat and also to direct the vaporized particles toward the surfaces to be coated. As will be seen from Fig. 2 this shield member is is formed in two portions with spring clamps adjacent their abuttin edges to retain the parts in aligned relation.

It is pointed out that during the coating operation it is necessary that the heating coil 2| be retained in proper position relative to the coating material within the crucible 20 and this position may be maintained by adjustment of the crucible 20 vertically by means of the chain 22 which connects the sprockets 23 and '24. The shaft 25 from the sprocket 24 extends through the base I and the chain 22 may be moved by means of the handle or knob 29 through the

beveled gears

26 and 21 and the shaft 28 to which the handle 29 is secured.

.The table 30 is adjusted by means of the members 3| and 32 as rotation of the handle 29 causes movement of the chain 22 and sprocket 23 which causes vertical movement of the table 30 relative to the vignetting member I I and the article or articles to be coated depending upon the direction of turnin of the handle 29.

Aligned with the window 4 is the reflector 33 which is supported on the uprights 35 whereupon illumination of the lamps 6 and I light or an image of said lamps from said lamps will be reflected from the surfaces being coated into the reflector 33 where said surfaces may be observed by the operator during the coating operation.

The post 34 provides current for the heating coil 34a which allows the heating of the lenses To support the objects to be coated on th plate Illa, where the objects are prisms as show! in Figs. 1 and 3 the said plate Illa is provided wit! openings of the shape of the object and with th object positioned in said opening with the surfaces to be coated in the direction of the sourc1 of coating material. A clamp 36 is then place: overthe upper surface of each of the articles II and secured in said position'by means of the sei screw31 and then the article I is placed througl the opening in the plate In and supported in salt position by the lower portions or ends of tilt clamp member 36 which rest on the upper surface of the plate Illa as shown in Fig. 4. As show: in Figs. 1 and 3 one of these clamp members ii provided for each object to be coated.

The plate Illa with the objects to be coated in position thereon may be placed within the housing member In by raising the cover l2 which is pivoted at 38 as shown in Fig. 1 and supported therein by the annular or marginal flange on the housing member ill.

Another form of apparatus for supporting the objects to be coated is shown in Figs. 6 and 7 which form is particularly adapted for use in the coating of lenses 39 one of which is placed in each of the openings 40 as shown in Fig. 7 and supported in said opening by means of the pivotal fingers 4| a plurality of which are provided for each lens and a few only of which have been shown in Fig. 6 for the purpose of illustration.

In Figs. 8 and 9 is shown another form of apparatus for supporting the object to be coated and which is particularly adapted for larger objects and which apparatus allows the coatin of both surfaces of an object without disturbing the coating operation and without opening the evacuated chamber.

In this form the object to be coated 43 is supported by the clamp members 44 one of which is connected to the shaft which in turn is connected to the beveled gear 45 which meshes with the gear 46 on the shaft 41 and to this shaft 41 may be connected a, pulley or chain 48 in a manner similar to the chain shown in Fig. 2 at 22 and then the shaft, beveled gears and handle as shown in Fig. 1 may be provided for effecting rotation of the member 43 from without the evacuated chamber or the shaft 41 may extend directly through the base I and have a gear arrangement such as the

beveled gears

26 and 21, shaft 28 and handle 29 associated therewith as shown in Fig. 1 which would eliminate the necessity of a chain drive such as 22 or 48 and thus simplify the construction. It is pointed out that by employing the heating coil 34a. in the form of a continuous spiral coil with one end grounded to the cover l2, which in turn is grounded by way of the uprights I3 for completion of the circuit to the current supply, and the other end connected to the current supply that a better control or more to be coated-before, during and/or after the coating operation as set forth in the application of Osterberg et 91., Serial No. 440,778, filed April 28, 1

uniform control of the heating may be obtained and also that by grounding this coil to the cover l2 that it isonly necessary to have one wire from the post 34 thus simplifying the construction.

It is pointed out that the lamps 6 and I should be daylight lamps.

From the foregoin it will be seen that we have provided simple, eflicient and economical means for obtaining all of the objects and advantages of the invention.

Having described our invention, we claim:

1. In a device of the character described, for use in adjustably positioning a crucible member in an evacuated chamber whereby the position of said crucible member may be adjusted without disturbing the vacuum insaid evacuatedchamber, said means comprising a support for said crucible member, a member for raising or lower- Tn'g said support member, means connected with said adjustable member and operable from without the evacuated chamber and means for operatingsaid adjustable member to adjustably position said support and crucible member.

2. In a device of the character described, a

vacuum chamber member, said chamber member.

means positioned between said means for sup-' porting a means for coating material and said for said heater while shielding the adjacent wall of said vacuum chamber from heat radiated by said heater.

'7. Coating apparatus comprising a vacuum chamber, means within said vacuum chamber for vaporizing coating material, supporting means within said chamber for holding a plurality 01 articles to be coated abovesaid first mentioned means, a housing within said vacuum chamber surrounding said supporting means and said articles on all sides except the side toward said first mentioned means, a heater within said housing means for supporting objects to be coated, .said

means being in fixed relative position to said coating material and said objects to be coated and being for the purpose of providing uniform distribution of the coating material over the surface to be coated, means for vaporizing the coating material and means for adjusting the relative position of said coating material and said means for vaporizing said coating material fromoutside of said vacuum chamber.

3. In a device of the character described, a I

transparent vacuum chamber, a source of vaporized coating material in the lower portion of said chamber, a rack in the upper portion of said chamber for supporting an article tobe coated with a lower surface exposed to the vaporized material from said source, a reflector adjacent said transparent vacuum chamber-for facilitating viewing of said lower surface by the operator, and a lamp adjacent the opposite side of said chamber and in alignment with said surface of the article and with said reflector for permitting the operator to observe in said reflector a beam of light from said lamp reflected thereto by said surface.

the operator to observe in said reflector said light reflected from the surface being coated.

5. In a device of the character described, the combination as set forth in claim 4 including a housing surrounding said vacuum chamber, said housing having openings for said lamp and said reflector respectively. I

6. Coating apparatus comprising a vacuum chamber, means within said vacuum chamber for vaporizing coating material, a support within said chamber for holding an article to be coated, a heater arranged adjacent said article for heating the same and disposed at the side of the article and support remote from said means, and a shield surrounding all sides of the support except the side toward said means and cooperating with said support for forming an enclosure for heat treating said articles, said housing forming a heat confining enclosureadjacent the upper surfaces of said articles and shielding the adja-' cent walls of said vacuum chamber from heat radiated by said heater. L

8. Coating apparatus comprising a vacuum chamber, means within said vacuum chamber for vaporizing'coating material, a rack within said chamber for supporting an article to be coated above said means, a housing within said chamber and surrounding all sidesof said rack and said article except the side toward said means, and a heating coil within the enclosure formed by said housing and said rack for heat treating the article supported by said rack, said housing including a lid above said heater, said lid and said heater being movable relative to said rack for exposing the article carried thereby, said housing and rack serving as means to shield the adjacent walls of said vacuum chamber from heat radiated by said heater.

9. Coating apparatus comprising a vacuum chamber, a member within said vacuum chamber for supporting coating material to be vaporized,

- an article support within said chamber for positioning an article to be coated by said material, a heater in said chamber between said article support and member for supporting said coating material for heating said coating material and positioned closely adjacent the latter, and a twopart shield extending around said member, coating material and heater for preventing loss of heat and for directing the vaporized coating material toward said article, said shield having inturned rim portions defining a discharge orifice in line with said article for the vaporized coating material, said two-part shield being separable to allow coating material to be placed within said shield without disturbing said heater.

10. Coating apparatus of the character described comprising a base and a bell jar positioned thereon so as to form a vacuum chamber.

, for causing vaporization thereof, and means for varying the operative position of said adjustable means relative to said vignetting means and said object support from outside said vacuum chamber.

HAROLD OS'I'ERBERG. ROGER E. MATTER.

(References on following page) 7 v v 8 REFERENCES CITED i I Nwnbgr- Name Date The followins reterences are of recbrd in he Kott "ff-"" 3811937 me of this v v 9 I 6; 1 1 2,239,452 Williams et a1. .Apr11 22, 1941 UNITED STATES PATENTS 5 2360,23; McLeod Oct. 38, 1941 Number Name j 9 Date 2,351, I Osterberg et a1. June 13-, 1944' 1,354,419 Pershing Sept. 28,1920 23928332 Lyon April 1 9 1,562,936 Ainsworth Nov. 24, 1925 OTHER REFERENCES {13:32: m ggfl 1 1 i93: 1o Ser.No.233,455,Berghauseta1;(A.P.O.),p11b.

Alexagder N v. 23, 193': May