US2001154A

US2001154A - Double-walled vacuum container

Info

Publication number: US2001154A
Application number: US724196A
Authority: US
Inventors: Arthur H Payson
Original assignee: AMERICAN THERMOS BOTTLE CO
Current assignee: AMERICAN THERMOS BOTTLE CO
Priority date: 1934-05-05
Filing date: 1934-05-05
Publication date: 1935-05-14
Anticipated expiration: 1952-05-14

Description

May 14, 1935.- A. H, PAYsoN DOUBLE WALLED VACUUM CONTAINER Filed May 5, 1954 ...zizuuslssuuvuun INVENTOR /PTHL/l? H. PAYSO/V I ATTORN EY Patentedk May `14, 1935 :lip-:1'

2,`oo1,1f54f o p `DOUBLE-WALIJED.SVAUUUll/I CONTAINER llrtlinlVHfPayson",` YConn.`.assignor to The American Thermos Bottle Company, Norwich, Conn`.`,wa corporation of fOhio' Appliiation` Maya 1934, serial Nb. 724.1963; [3f crains. loller- 681m My invention relates todouble-,Walled vacuum containers of glass, and its object is to provide a container of that type in which the silvered walls of the vacuum space have a clear strip like 51a window for observing the contents of the container. This window is produced by inserting a suitable member into the vacuum space and holding it in rm contact with opposite portions of the walls while these are being treated with a silvering solution. When the silveringoperation is finished, the glassareas covered by the inserted member remain unsilvered and transparent to serve as a sight opening.

`In practice I have obtained satisfactory results .I l5 by means of a flexible rubber tube, which is easily inserted into the vacuum space of the container through the usual evacuating tubulation. Ihe inserted tube is then inflated and thereby forced into rrn contact with opposite areas of the walls, and these areas are not reached by the silvering solution, but remain clear glass. The tube is thereupon deated and withdrawn.

The novel features and practical advantages of `Iny invention will be understood from a description of the accompanying drawing, in which Fig. 1 is `a vertical section of a double-walled glass container with a rubber tube inserted into the Vacuum space prior to the silvering oper- 30 ation;

Fig. 2 is a front view of Fig. 1,` showing the vertical window formed in the container by use of the rubber tube; 1

Fig. 3 shows a modification in which thel inserted tube is looped at its inner end to cover a circulararea which shall remain unsilvered; and j Fig. 4 shows a double-walled container having a; sight opening formed by the looped tube of 40 Fig. 3.` p

, In all the views there is a double-walled cylindrical container of glass, comprising an outer wall Il] and an inner Wall I2 integrally united and separated by a space I3, which in the finished jar is evacuated to provide heat-insulation for the contents.v `The inside wall surface of the vacuum space I3 is silvered to improve the heatinsulating propertiesof the container, and this silvering is usually done by pouring a silvering 5 `solution through the open tubulaton I4, and agitating the jar or bottle until a `coating of silver is precipitated uniformly on the walls of `thevacuurn space. The excess solution is then poured oi, the silvered chamber is rinsed with clear water, and nally the container is put through the usual baking and exhausting operations-.1., i I I Insome instancesit has been found neces.- sary to observe thecontents `of the silvered container from the outside,`and to make that pos- 5 sible I form a window or sight opening lengthwise of the container by blocking off opposing portions of the vacuum walls during the silvering operation. One way of doing this is shown in Fig. 1, where a straight soft rubber tube I5 is 10 inserted through the tubulation I4, and is then inflated to force it into firm contact With the walls of the vacuum space I3.` The inflated tube may be tied with a piece of string I6 at its outer end or held closed in any other practical way. The silvering solution is then poured into space I3 through tubulation I or through another hole in the outer wall Ill. 'Ihe container is then rolled or otherwise agitated to bring the solution into contact with the entire wall surface of the vacuum space I3, except where the inated tube I5 covers the glass. When the silvering operation is finished and the deflated tube withdrawn, there is left an unsilvered trans'- parent strip I'I through which the contents I 8 25 of the jar may be observed.

In Fig. 3, the inserted rubber tube I5 is doubled and is tied at I 9 (an elastic band will do) to form a` loop 2U, which covers a circular area on each wall of the vacuum space. Consequently, when the looped tube I5 is withdrawn after the silvering operation (the tube being deflated for that purpose), the window 2| formed in the silvered walls has a disk-shaped'enlargement 22 at v the top. Manifestly, other forms of window may be produced by varying the shape of the inserted member to block 01T such portions of the glass as may be required in any particular-case.

I want it understood that my invention is not limited to the details set forth, for changes vand 40 modifications may be made Within the scope of the appended claims. Throughout the descripf tion and claims I use the term vacuum space to designate the space between the twowalls of the nested glass cylinders, irrespective of whether a vacuum is actually drawn therein or not. In some double-walled bottles and jars this space is `sealed off at ,atmospheric pressure, or it may be lled with carbon dioxide gas or other medium having heat-insulating properties. All Such double-walled containers have a vacuum space Within the broad meaning of the term as used in the claims. Further, when I speakv of the silvered walls of the vacuum space, I do not necessarily mean a coating of silver, but I include PJrArENrIQFFICE any silver-like or mirror-like coating, such as, for example, nickel, magnesium, copper, and so forth.

I claim as my invention:

1. In the manufacture of double-walled vacuum containers, the method of forming an unsilvered window in the silvered inner walls of the vacuum space, which method comprises inserting a member into said space and maintaining it in rm contact with opposing portions of said walls along a sufficiently wide area substantially lengthwise of the container, and treating said inner walls with a silvering solution while Said member s held in place, whereby the opposing wall surfaces covered by said member remain unsilvered and transparent to serve as a window or sight opening, the inserted member being then withdrawn.

2. In the manufacture of double-walled vacuum containers, the method of forming an unsilvered window in the silvered inner walls of the vacuum space, which method comprises inserting an expansible elastic member into said space and forcing it into rm contact with opposing portions of Said walls along a sufficiently wide area substantially lengthwise of the container, and treating said inner walls with a silvering solution while the expanded member remains in Contact with said walls, whereby the opposing wall surfaces covered by said member remain unsilvered and transparent to serve as a window or sight opening, the inserted member being then withdrawn.

3. In the manufacture of double-walled vacuum containers, the method of forming an unsilvered window in the silvered inner walls of the vacuum space, which method comprises inserting an infiatable rubber tube into said space, inflating the inserted tube to force it into firm contact with opposing portions of said walls along a suiciently wide area substantially lengthwise of the container, and treating said inner walls with a silvering solution while the inflated tube remains in position, whereby the opposing wall surfaces covered by the inflated tube remain unsilvered and transparent to serve as a window or sight opening, the inserted tube being then deflated and Withdrawn.

ARTHUR H. PAYSON.