US1620581A - Chemical heating pad - Google Patents

Description

M. A'. SMITH CHEMICAL HEATING PAD March 8, 1927..r`

Filed Dep. 17. 1924 INVENTO R /W/ DREa/ SM/r VBY ATTORNEYS WITNESSES Patented Mar. 8, 1927.

UNITED STATES PATENT OFFICE.

MBDRED'AURELIA SMITH, or AIQBANY, NEW YORK.

p cH'EMeAL HEATING ran.

Application led December 17, 1924. Serial No. 756,587.

' simple and eiiicient means for causing the venting thewater of condensation inside ofv ,iron' borings that have prevlously bag to fold twhen-closing, at a point where said Ibag cannot leak. A further object concerns the provision of simple and eiiicient means for maintainlng an even temperature in all parts of the chemical mixture.

-A still further4 object concerns the provision of simple and etlicient means for prethe envelope from leaking out while in use. -A still further object concerns the provision of simple and'ecent means for regulating the supply of air that enters the device.

The invention is illustrated in the drawi of whichigure 1 is an elevation of the device; Fig. 2 is a section; Fi 3 is a perspective view of the inner bag s owing how the layers are forced apart when the bagbis held by the flap causing a strain on the ias of the bag;

Fig. 4 is an enlarged elevation of the funnel corner of the bag;

5 is a section on the line 5-5 of Fig. 6 is an enlarged section of the funnel corner showin the manner in which it is folded when t e opening is closed and held closed; and

F10'. 7 is a rspective view of one of the Ventilating bolli plugs.

The form of the invention shown in the drawings is a lpreferred form, although it is understood t at modifications in the construction and arrangement of the parts and in the character offthe materials used may be adopted without departing from the spirit of the invention as set forth in the appended claims.

. My'A invention comprises a fabric bag, canvas or "the like, one-third filled with the following chemical mixture. 90 per centbne een Vcoated with a solution of CuClz-l-2H2O and H2O, 9 per cent KCl or 9-per cent NaCl and 1 per cent CaCO3 or 1 per cent (MgonMgoHh-i-:aI-Lo. This fabric bag is prefera ly rectangular in shape and sewed along its edges. In one corner of the bag the two layers of material are separated to form an opening through which water can be forced. Adjacent this opening two layers of material are sewed together along lspaced lines which converge inwardly to- :ward the center of the bag to form a funnel.

This corner of one of the layers of material 1s cut away shorter than the corresponding corner of the other layer so that the one corner portion will extend beyond the other to be used as a flap to grip the material irmly in the hand causing a strain on the bias of the pad and forcing the two layers to separate at this point, the edge of the other corner portion being bent over to insure a better seal when closing the funnel.

A U-shaped metallic clip having one long side is attached to the extended flap ortion of the bag. The short side of the cip extends down on the inside of the bag to a point where it is to be bent over when closing the bag and the other side extends an equal distance beyond that point. The clip is therefore double for one half its length when fastened on the flap of thebag. The clip is made from a gauge metal that will bend easil in a sin le thickness but where it is double it will almost impossible to bend it. For this reason the clip will always bend just where you want it to fold and thus eliminate the danger of spilling out the hot chemicals during use. Therefore it can be seen that this new type of clips performs another function other than merely holding the bag closed.

The bag is then placed within an envelo which is waterproof. This envelope, on its inner surface, is provided with a plurallty of irregular rows of ribs which space a considerable portion of the envelope away from the outer surface of the bag so that air can get to the chemical mixture through the fabric bag. The envelope is provided with a plurality of Ventilating openings the inner edges of which have a raised head -around them to prevent the condensation which forms on the inside of the envelope from leaking out through the openings while in use.

In starting the chemical heater the funnel is opened b bending back the metal clip, one tablespoon u1 of water is poured in throu h the opening. The funnel is closed and t e bag inserted into the waterproof envelope. The chemical heater should be kneaded at once to distribute the 'water uniformly through the mixture. Spontaneous generation of heat will result 'by the H20 starting to oxidize the iron borings. The presence of the coating of CuClz-i-2H2O on the iron borings greatly accelerates the s eed in starting but it can not be used in arge quantities since it is not stable in air. Therefore a quantity of NaCl or KCl is used to accelerate the oxidization of the iron borings over a long period of time. The heat nerated by this oxidization evaporates the ll'lzO and dries the chemical mixture out thus automatically stopping the oxidization after several hours of heating. This may be repeated several times or the heater may be kept hot continuously -for several days by adding more water when it cools down. It may be kept hot until the iron is completely oxidized. The 'CaCO3 or (MgooshMgmmzJfsHzo jected to dampness. The iron borings would not oxidize if it was not for the oxygen in the air that unites with the iron forming iron oxide. The Ventilating ribs on the inner surface of the envelope therefor aids greatly in uniformly distributing the air supplying oxygen to the chemical mixture which in turn generates a uniform temperature throughout the said mixture.

As shown in the drawings, the preferred form of the invention comprises a bag l. formed of two layers of material sewed together except at one corner (not shown). At this corner the material of one ont the layers is cut awa permitting the other corner of the other layer of material to extend therebeyond, as at2, to form a Hap extension which can be gripped in the hand, causing a stress on the bias of the bag and forcing or causing the two layers to separate as shown in Figure 3. The layer which is cut away, however, has its upper edge at the corner turned over, as at 3, to insure a better seal when closing the funnel. The extended flap portion is provided with a metallic clip 4 which is'bent double thereover in a manner so as to eliminate at all times the dangers of improper closing of a'device of this character. Lines ofstitching 5 and 6 extend inwardly toward the center of the bag and converge toward each other. -'lhese lines are spaced apart and join the layers together to form a funnel, the water bein poured in between the layers of material within an area defined byv these rows of stitching. As the Hap 2 is held in the hand the layers of material tend to separate and causethe stitching to form a simple funnel. When the water has been poured in,'the extended ap 2 is bent over, as shown in Fig. 6, to cover the this Leanser shorter Hap portion and the opening form@ therebetween7 the rigidity of the metal clipl 4 keeping the opening clod.

The bag 1 is then put in an envelope 7 of waterproof material which is provided with a pluralityof openings such as 8 for Ventilating purposes. These openings are connected on the inner surface of the bag by rows, such as 9 and 10, of irregular ribs or teats-which keep the Amajor portion of the surface of the envelope away from the outer lsur'ace of the bag so that air getting in through the openings 8 will suppl oxygen to the chemical mixture uniform y which in turn generates a uniform temperature throughout the chemical heater. The envelope 7 is provided with a plurality of ventilatmg openings 8 the inner edg of which have a raised bead around them to prevent thecondensation which forms on the inside il i of the envelope 'l from leaking out through the openings 8 while in use.

The temperature of the chemicalheaterv sults in the construction and operation oit the bag.

What I claim is 1 1. A chemical heating pad formed of two layers of material sewed together along their edges exce t at one corner, a portion of the material o one layer being cut away to mrmit the corner of the other -layer to ed therebeyond in the form of a nap, whereby the pad can be supported by this nap thereby causing a stress on the bias of the uw? which `forces the two layers to separate at point. 2. A chemical heating pad formed of two Mid layers of material sewed together along their Y edges exce t at one corner, a portion of the material o? one layer being cut away to permit the corner of the other layer to extend therebeyond in the form of a Hap, whereby the pad can be gripped by this flap, causing a stress on the bias of the pad which forces the two layers to separate at this point, and rows ot stitch' t: extendin in a conver'n manner inwarly from t is cornerl f' t e pad to join the layers and form a sort of spout or funnel1 passage through which water can be oure P 3. A chemical heatin pad formed of two la ers of material sewe together along their e ges exce t at one corner, a portion of the material o one layer beingcut away to perlll@ ist

mit the corner of the other layer to extend la@ therehedyond in the form of a Hapgwhere'by the A, a can be 'p ed b this a causing a stipess on the bgilals lof thgpad whipoh forces the two layers to separate at this point, and form a funnel passage, and a U shape metal eiip having one side shorter than the other, crimped over the extension Hap reinforcing the ap with metal on both sides to a point.

where the Hap portion is adapted to be bent over to close the funnel passage. 4i. A chemical heatin pad formed. of two ia ers of material sewe together along their ges exceptat one corner, a portion of the material of one layer being out away to permit the corner of the other layer to extend therebeyond in the form of a Hap, whereby the pad can be gripped by this Hap, causing a stress on the bias of the `pad. which forces the two layers to separate at this point, and

form a funnel passage, and a U-sha-ped metal clip crimped over the extension flap reinforcing it with metal on both sides to a point where the Hap portion is adapted to be bent over with the other layer of material at the corner to close the funnel passa e.

MKLDRED AURELIA SMTH.

Images