US 2178140 A
Description (OCR text may contain errors)
OC. 3l, 1939. J, FETZER 2,178,140
PRESERVE JAR Filed June 9, 1938 JIO INVENTOR Patented Oct. 31, 1939 UNITED STATES PATENT OFFICE PRESERVE JAR John Fewer, Pittsburgh, Pa. Application June 9, 193s, serial No. 212,727
s claims. (cl. 21a-4u) My invention relates to containers, and parand outer ,circular peripheries 5a and 50a of the ticularly to glass jars for preserves. seat.
The usual container of this sort consists in a The lid 2 is formed integrally of glass. It glass jar, a sealing ring, and a lid. The rim of includes a seat vcomplementary in form to the 5 the jar includes an annular seat, upon which the seat on the jar. That is to say, the seat on the 5 gasket is by the lidy compressed to provide an lid includes two annular, vertically offset Surair-tight closure for the jar. More particularly, face portions l and 1G, between which a sharply my invention consists in specific refinements in defined circular shoulder 100 is formed. The the structure of such containers, by virtue of surfaces l, mare parallel to the surfaces 5, 50, ll which the desired hermetic assembly of the gasand the circular shoulder 100 is of slightly larger 10 ket and lid with the jar may be accomplished diameter than the shoulder 500, to the end that more readily and with greater eciency. In the the two Complementary seats 5, 50 and 1, 10 shall practice of my invention 'the normal tendency cooperate most eiTectively in providing the defor air to be trappedin the jar is minimized. sired hermetic engagement with the gasket-ring l The container is particularly adapted for what 3. Within the compass of the seat 1, 'l0 the lid 1li is known as oven canning or cold packing. includes a recess 8 into which the rim 6 of the In the accompanying drawing a container emjar extends, and radially outward from such seat bodying the invention is illustrated. Fig. I is a the lid is provided with an integral skirt 9 that fragmentary view, showing the jar partly in side extends downward over and shields the plane elevation and partly in section, the lid and gasof union between jar and lid. 20 e ket in vertical section, and the keeper in side ele- The gaSket-Ing 3 iS 2 thin, relatively at ring, e
vation. Fig. II is a view in plan ofthe gasket. as distinguished from a thick ring whose body Fig. III is a fragmentary view,` comparable with is of circular rcross-section or the like. The Fig. I, illustrating a modication in the form of ring is formed of a `reletiVelY elaStC materialthe lid and the gasket-receiving seat on the jar. afrubber 0f Such COmDOStiOn and heat CIJ-ring 25 And Figs. IV and V are views similar to Fig. III, that it possesses substantial elasticity. illustrating still other modincations. Inthe assembly, the seat l, 10 engages the The container of the invention consists in a ring from above.. and compresses it against the glass jar l, a lid 2, a gasket-ring 3, and a keeper 4. seat 5, 59 0n the jar. By Virtue of the form of The keeper 4 consists in this case in a simple the Seats, the COIIIDIGSSOH of the gasket is, ad- 30 clamp formed of a strap of metal. The ends of vantageously, concentrated in a circtunferential the @lamp Carry anges 4a that engage beneath line that eXtelldS COllCeIltlC With and intermedia circumferential shoulder ia on the jar, and ate the inner and outer peripheries of the seats. the body of the clamp between such ends bears MOTS specifleelly, the COmDleSSOIl 0f the gasket yieldingly but firmly upon the top of the lid, is concentrated immediately between the shoul- 35 serving to secure the lid and gasket-ring in posiders 50D and l, and it is the medial body portion upon the mouth oi the jar. The body of the tOIl 0f the gasket-ring that 'receives the conlid includes a central bess 20 of frusto-conical Centrated i compression. Otherwise expressed. iorln; that is, a boss whose body tapers upward the medial y100th 130111011 0f the gasket iS pinched from the surface of the lid proper to a flat sumand Compressed in a une 0f Compression that en' 40 mit, in which a central indentation 2a is formed. Compasses the um @the jor? that is: o Circo- Tiie Clamp i is provideci with a wat 4b which in iar llne of lcompression ln which the desired seal- :le assembly nests in the indentation 2a and premg engagement of the Seats Wlth the gasket'rng ents the @iam from Sii in from 1id se in is accentuated byia vertical shearing or wedging 5 Cgi/cion p ep g our g action of the two shoulders on the medial body 45 y portion of the gasket-ring. At en Interval below the nm e of the Jar an In the usual containers of this class, I have annular or circumferentially extending seat is found that when the iid is positioned and se provided on the jar. This seat includes two an- Cured upon the jar, a Substantial body of' an. nular surface por'tlons and 5i! that.' as VleWed is trapped kand enclosed in the region between 50 in transverse section (Fig. I), are inclined to the the 11d and the surface of the preserves in the axisof the jar. These two Surface portions are jar. Manifest1y,the presenceof air in the sealed vertically olset from onev another and provide jar is objectionable. In my structure, I have 'in a circular ridge or sharp shoulder 580 which lies large measure eliminated the entrapping of air.
55 intermediate of, and 'concentric with, the inner Specically, the rim `6 of the jar is adapted to 55 t into the recess 8 formed in the lid, and, by filling the jar (with the material to be preserved) to the top of the rim, the lid, as it is brought to position on the jar, physically displaces substantially all air from above the surface of the material in the jar.
My container lends itself with particular advantage to the putting up of preserves in the cold packing or oven canning process. In such process, as hitherto practised, raw vegetables, fruits, or other foodstuffs, are placed in jars with suitable quantities of water, sugar, salt or other required ingredients. Lids are placed loosely over the mouths of the jars, and the jars are put in a boiler or oven and heated to a temperature of 212 F. or more for an interval of time varying from several minutes to an hour, more or less, depending upon the particular fruit or vegetable being treated. At such temperature the liquid within the jars is raised to the boiling point and generates steam which sterilizes and cooks or partially cooks the raw foodstuffs. Under superatmospheric pressure within the jars, steam escapes and carries all air out of the jars, the lids being loosely assembled on the jars for this purpose. When the foodstuff has been treated a suicient interval of time, the jars are removed from the boiler or oven and cooled, and the lids are tightened in place. In the course of tightening the caps air lters into the jars and is inclosed with the preservesJ with known objectionable consequences.
In practising this cold packing process with my jars, the steps followed are those already described and known, save that the lids may be clamped on the jars before the heating begins. That is, before the jars l with their contents are put into the boiler or oven, the lids 2 are secured on the jars, by means of clamps 4.
When heat is applied and steam generated within the jars, the lids are lifted by the pressure within the jars, and steam escapes, between the seats 5, 50 and '1, 10, into the outer atmosphere, carrying with it the air confined with the edibles within the jars. It will be understood that the elasticity or resiliency of the clamps 4 is such that the resistance offered to the rise of the lids is of a value well below that which requires an excessive or dangerous' steam pressure within the jars to lift the lids from their seats. When the heating treatment has been conducted through the required interval of time, the jars are allowed to cool. Immediately upon the termination of heat application, the temperature of the jars begins to fall and the steam pressure within the jars drops, with the consequence and effect that the clamps immediately urge the lids into jarsealing engagement with the gasket-rings 3. There is no waiting for the manual tightening of the lids-the sealing of the jars is effected automatically and instantaneously, and there is no chance for air to filter into the jars. As the falling temperature approaches room temperature, the steam remaining within the jars condenses, whereby a vacuum or a condition of subatmospheric pressure is established within the jars, with the result that the pressure of the outer atmosphere becomes effective to press the lids with great force against their gasket-rings 3, and form a perfect seal. The seal is so effective in my structure that the clamps 4 may be removed before the jars are put into storage, the difference in atmospheric pressures between the inner and outer faces of the lids being adequate to secure the lids in place. Thus, the clamps need not be used as permanent elements of the containers, but may comprise appliances used only during the canning operation.
There is another important feature of the invention to be considered. I have found that in the heating process, when the lids are lifted upward by steam pressure, the escaping steam tends to expand the gaskets radially outward, in such manner that the outer peripheries of the gaskets are caused to bear tightly against the inner cylindrical faces of the skirt portions 9 of the lids. This engagement of the gaskets with such skirt portions inhibits the desired ready escape of steam and air from within the jars, and in some cases causes the pressure Within the jars to become dangerously high. In remedying this situation, I advantageously provide one or more recesses, slots, or .grooves 30 in the gasket-ring. These recesses extend inward from the outer periphery of the ring, and in the assembled container are positioned between the ridge or shoulder 590 and the outer periphery 55a of the seat on the jar. In the conduction of the process described, these recesses comprise vents for the escape of steam and air from within the jar, even when the gasket is expanded against the skirt 9 in the manner alluded to. It will be understood that there is no appreciable resistance to the movement of such fluids between the seat '1, lil and the upper face of the gasket-ring.
In modification of the structure described, the circular ridge that effects the above-described concentration of gasket-ring compression may be formed in one only of the two cooperating seats on the jar and lid. As shown in Fig. III, the ridge may be formed in the seat on the jar, and may consist in a crest H) formed by the line of intersection of the two annular surface por-- tions 5l and 52 of such seat. As viewed in transverse section (Fig. III), the two annular surfaces 5| and 52 are fiat; they extend angularly to the axis of the jar and angularly to one another, and meet in a sharp circular line or ridge that lies intermediate the inner and outer peripheries of the seat. The seat on the lid may be similarly formed, with a ridge HU (Fig. V) directed downward toward the ridge 510, or it may be formed, as shown at 'H (Fig. III) as a single, iiat annular surface inclined to the axis of the assembled jar and lid.
Again, the two annular surface portions of the seat on the jar may be curved, as viewed in transverse section in Fig. IV, and the two surfaces may be merged in a round ridge 520. Indeed, the two annular surfaces may have a common radius of curvature, so long as the crest of the curve lies intermediate the inner and outer peripheries of the seat, to provide the above-described concentrated compression-though it be a less acute concentration of compression-of the gasketring 3.
It is important to note that in all forms of my structure, the circumferential seat on the jar inclines downward from its inner periphery to its outer. Thus, in the manufacture of the jar, the essential draft or clearance is provided, to permit the usual vertically parted ring-mold to open and readily free itself from the molded glass.
I claim as my invention:
l. In a container including a glass jar and a lid sealed upon the mouth of the jar with a gasket-ring; the renements herein described in which said jar includes a circumferentially extending seat that lies below the plane of said mouth, that extends radially outward from the rim of the jar encompassing said mouth, and that includes two annular surface portions meeting intermediate the radially inner and outer peripheries of such seat in a circumierentially extending ridge; in which said lid includes a circumierentially extending seat; and in which said gasket-ring is compressed between said seats, the compression of said gasket-ring, elsewhere of less value, being concentrated intermediate the inner and outer peripheries of the opposing seats between said ridge on the jar and said seat in the lid, and the body of said gasket-ring being recessed radially outward from said ridge upon which it is compressed, to provide during the assembly of the lid on the jar a vent for the escape of fluid from within the jar, substantially as described.
2. In a container including a glass jar, a lid with a peripheral skirt; complementary, circumferentially extending seats severally formed on jar and lid with an annular ridge intermediate the inner and outer peripheries of one of said seats, and an elastic gasket-ring compressed between said seats; the renement herein described in which the body of said gasketring is recessed between the said ridge and the outer periphery of the seat, whereby during the assembly of the lid on the jar escape is provided for uid from within the jar, even when the gasket-ring expands radially and its outer periphery is pressed against the skirt on the said lid.
3. In a Mason jar including a rim surrounding the mouth of the jar, a gasket-receiving seat extending (at an interval below the plane of such mouth) radially outward from the wall of the jar, and a lid including an annular gasketcontacting surface for cooperation with 'said seat; the refinement herein described in which said seat includes inner and outer annular surface portions concentric with the axis of the jar, said surface portions extending, as viewed in transverse section, angularly to each other and meeting in a circumferentially extending ridge and providing, between the inner and outer peripheries of the said seat, with the lid and gasket in place, a concentrated compression of such gasket on a circular line, the gasket-engaging surface portions of said seat and lid diverging outwardly from said circular line of compression and providing, as viewed in transverse section, wedge-shaped gasket-receiving spaces.