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Publication numberUS2329766 A
Publication typeGrant
Publication dateSep 21, 1943
Filing dateApr 27, 1942
Priority dateApr 27, 1942
Publication numberUS 2329766 A, US 2329766A, US-A-2329766, US2329766 A, US2329766A
InventorsJacobsen Walter
Original AssigneeJacobsen Walter
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Electrically heated flying suit
US 2329766 A
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Description  (OCR text may contain errors)

Sept. 21, 1943. w. JACOBSEN ELECTRICALLY HEATED FLYING SUIT Filed April 27, 1942 3 Sheets-Sheet 1 nasal-1.112.112!

...=1 azzzlzuaalizxzzzzazza INVENTOR. (lzcokezz P 1943- w. JACOBSEN ELECTRICALLY HEATED FLYING SUIT Filed April 27, 1942 3 Sheets-Sheet 2 INV ENT OR.

00/1 62 c/bcafiyezz BYM film PLQLQ Sept. 21, 1943. w. JACOBSEN ELECTRICALLY HEATED FLYING SUIT Filed April 27, 1942- 3 Sheets-Sheet 3 3 U r. C "L IllllllllllllllllllllllllHlIH 2.32" WWW Patented Sept. 21, 1943 UNITED STATES PATENT OFFICE ELECTRICALLY HEATED FLYING SUIT Walter Jacobsen, Chicago, Ill. Application April 27, 1942, Serial No. 440,587

11 Claims.

My invention relates to electrically heated fabrics and particularly to such fabrics made up into articles of clothing or other covering members for keeping the human body, or parts of the body warm. More particularly this invention relates to electrically heated suits, such as are employed by aviators flying at high altitudes or in cold weather, and to other electrically heated body-warming devices such as electric blankets, electric heating pads and electric bandages for therapeutic purposes.

One of the principal objects of this invention is to provide fabric containing electric resistance elements, the fabric being in such a form that it can be easily fabricated into various articles of clothing and into articles of clothing of different sizes to fit difierent people. More particularly, it is an object of this invention to provide a fabric tape containing an electric heating element and so constructed that it can be readily sewn into position on a foundation garment, a plurality of lengths of tape being used to cover the desired area of the garment.

Another object of this invention is to provide an electrically heated fabric covering member, such as a portion of a suit, blanket, or the like, which shall have substantially more flexibility than has previously been provided in articles of this type and which will therefore conform more easily to the shape of the body.

The principal feature of the present invention comprise the provision of a fabric tape having a fine electric wire woven into it, the wire extending along the tape in short steps and extending across the tape in comparatively long runs so that each running foot of the tape contains several feet of wire. Because of this, the tape is quite flexible in a longitudinal direction and the tape is narrow enough so that its lateral stiffness, due to the straight length of wire running across it; does not stiffen any large continuous area of the garment to which it is sewn.

Another important feature of the invention is the way in which the tape containing the electric wires is woven so that there is no wire along its edges, which allows it to be sewn by machine to a foundation garment without any danger of the wires being injured.

These and other objects and features of the invention will be apparent from the following description and appended claims and the accompanying drawings, in which,

Fig. 1 is a perspective view of acomplete flying suit embodying the invention, the various parts of the suit being separated slightly from each other in order to show them more clearly;

Fig. 2 is a broken-away perspective view showing a detail of the construction of the suit shown in Fi 1;

Fig. 3 is a plan view of the interior of a glove forming a portion of the suit shown in Fig. 1;

Fig. 4 is a plan view of a portion of the tape used in the suit shown in Fig. 1;

Fig. 5 is a longitudinal diagrammatic section on an enlarged scale, on the line 5-5 of Fig. 4, looking in the direction of the arrows;

Figs. 6 and '7 are diagrammatic cross sections on the lines 6-6 and 7-1 of Fig. 5, looking in the direction of the arrows;

Fig. 8 is a plan view of an electrically heated bandage embodying the invention;

Fig. 9 is a plan view of an electrically heated blanket embodying the invention; and

Fig. 10 is a plan view of an electric heating pad embodying the invention.

The embodiment of the invention shown in Fig. 1 comprises a jacket I I, a pair of trousers l2, a pair of gloves IS, a pair of stockings l4, and an external connector l5 through which the various portions of the suit are connected to a source of electric energy. The jacket I! is generally conventional in shape and comprises a body portion i6 and two sleeves H. The sleeves I! may be of the same size as the leeves in an ordinary coat or jacket, but it is preferable to taper them towards the wrist so that they will fit closely and have less area than an ordinary sleeve. With the smaller area there is less loss of heat.

' Each sleeve is therefore provided with a slide fastener i8 extending approximately half way up from the wrist in order to facilitate the putting on and taking off of the garment. The body of the jacket is provided with a single slide fastener l9 in front in the conventional manner.

As shown more clearly in Fig. 2, the jacket is formed in four layers, first, an outer layer 2| of plain cloth; second, an intermediate layer 22 of warm knitted or woven fabric made, for instance, of wool; third, a layer of woven heating tape 23; and fourth, a cloth lining 24.

The heating tape 23, as shown in Figs. 4 to 7, is a strip of woven fabric formed by three sets of woolen weft threads 25, 26 and 21, a woolen warp thread 28, and a pair of fine insulated wires 29 forming an additional warp. The two sets of weft threads 25 and 26 and the warp thread 28 are interwoven to form a plain square weave, except that the weft threads are much closer together in the actual tape than are the warp threads, so

that the surface of the fabric is formed entirely by the weft threads.

The third set of weft threads 2? passes under alternate warp threads 28 with one of the other sets of weft threads 2%, but, where it passes over the other warp threads 28, it also passes over the fine wires 29 and thus secures them to the face of the fabric formed by the other threads 25, 2S and 28. The resultant complete fabric is thus smooth on one side, but every alternate pick or run of the woof thread 28 has a pick or run of the wires.29 over it. The wires 29, where they run across the tape, are completely covered by the third weft Ell because the weft threads 27 are twice as numerous as either the weft threads or the weft threads 26.

As may be seen from Fig. 4, the successive picks or runs of the wires 29 across the tape do not extend to the edges of the tape, so that a selvage fit without any wire in it is left along each side of the tape. The selvage 3! has a plain square weave formed by the weft threads 25 and 26 and the warp thread 28, the third weft 2'7 being absent from this portion of the tape.

In Fig. 1 the outer and intermediate layers 2i and 22 have been broken away from a part of the Jacket to show the arrangement of the tapes 23. There are four lengths of wide tape 23 on each side of the jacket, each length starting in front at the waist, running up over the shoulder and down to the waist at the back. The wires in each tape are connected at their ends to a pair of conductors which encircle the garment at the bottom and are enclosed in a binding 32 sewn to the body of the garment. The two conductors in the tape 32 are connected to a flexible electric cord 33 which terminates in a plug 3%. The plug 3% fits into the connector it, which is on the end of an electric cord 35 through which electricity for the entire suit is supplied.

The four wide tapes 23 which extend over the shoulder of the jacket H are spaced evenly out from the center line at the front and the back of the jacket, leaving an area at the side which is heated by a group of narrower tapes 3?, each of which starts at the waist, extends up to the shoulder, loops down onto the sleeve, and back to the shoulder, and then extends down to the waist again. The ends of each narrow tape 31, like the ends of the wider tapes 23, are connected to the wires enclosed in the binding 32 around the waist of the jacket. Since the tapes 3?, which extend onto the sleeve ll, are considerably narrower than the body tapes 23, the length of electric wire per running foot is considerably smaller than the length of electric wire per running foot of the body tapes 23, and these lengths per running foot are proportioned so that the total length of wire in each of the narrow sleeve tapes 3? will be'approximately the same as the total length of wire in each of the body tapes 23.

All of the tapes 23 and 31 carrying the electric heating wires are secured in place by being stitched to the intermediate or foundation layer 22 of the jacket, the stitches 36 being along the edges of the tapes so that there is no danger of injuring the electric wires 29 when the sewing is being done.

The trousers B2 are of the same general construction as the jacket H and are formed of layers arranged in the same way. Besides the conventional front slide fastener 39, each leg desired, and still be easy to put on. The tapes 52 which form the heating elements of the trousers are similar to the tapes 23 on the body portion of the jacket and extend down in loops from bindings at which encircle each leg just below the hips. The bindings 43 contain a pair of conductors to which the ends of the wires in the heating tapes 52 are connected. The conductors in the bindings $3, in turn, are connected to an electric wire as which terminates in a plug d5 by means of which a connection can be made with the connector l5. The heating tapes 32 are terminated on a line below the hips bmause the upper part of the trousers i2 is covered by the lower part of the jacket if when the suit is in use and heat is supplied over this area by the jacket.

Each glove i3 is provided with a single length of heating tape 66 constructed in the same way as the heating tape 23, illustrated in detail in Figs. 4 to '7, but considerably narrower. s6 is arranged on the inside of the glove with one loop extending down on the back of each finger and the thumb, as shown in Fig. 3. The glove !3 is provided with the female parts 67 of three snap fasteners sewn on the back of the glove near the wrist. One end of each of the two wires 58 and 39 inthe tape 56 is secured to one of these parts of the snap fasteners, and the other ends of the two wires til and 39 are each secured to one of the other two parts of the snap fasteners. Thus one snap fastener provides a common connection to each of the two wires it and t9, and the other two snap fasteners provide connections to the other ends of these wires.

Each sleeve ll of the jacket has a small pad 55 secured to its lower end by a wire 52 and carrying the male parts 53 of the three snap fasteners. The electric wires 52 extend up the sleeves, down the body of the jacket, and are connected to a single electric cord 5d which emerges from the jacket along with the electric cord 33 and carries a plug 55 which fits into the connector l5. One of the parts 53 of the snap fasteners on each pad Si is connected to one conductor in the electric wire 52 and the other two snap fastener parts are connected to the other conductor 53 so that the proper connection can be made to the snap fastener parts ll on the gloves l3. If the three snaps on the glove I3 and pad fat are connected together, both of the wires 48 and 49 will be provided with current, but, if less heat is desired, one of the snaps to which a single wire is connected may be unsnapped to break the connection to that wire and permit current to flow only through the other wire.

The socks iii are each provided with a single length of tape 56 similar to, but narrower than the tape 23 illustrated in Figs, 4 to 7. The tape 56 begins and ends at the female parts 51 of a pair of snap fasteners sewn to the stocking it near its upper end, and it extends up and down v the leg of the stocking and along the foot in suitably arranged loops. The loops of tape 56 may, if desired, extend over the sole or under' part of the foot of the stocking it, but it has been found that this makes the stocking slightly uncomfortable to walk with and that sufficient heat can be provided by having loops of the heating tape 56 on only the sides and top of the foot.

At the bottom of the legs of the trousers it, there are provided pads 58 on which are sewn the male parts 59 of the snap fasteners whose female parts 51 are located on the stockings M.

The tape Each pad 58 is carried at the end of an electric wire 6| which extends up the inside of the trouser leg. The two electric wires 6| Join toform a single wire 82 which extends out from the trousers along with the wire I through which current is supplied to the heating tapesof the trousers, and a plug 83 is provided on ,the end of the wire 62 for making a connection with the connector ii.

The various parts of the flying suit could, if desired, be made as a one piece garment, like a child's sleeping suit or like a mechanic's jump-e er, but it is preferable to make the jacket separate from the trousers, as shown, and to make the gloves and socks separate from the Jacket and trousers. The garments can then be put on,

one at a time, and connected together and to the connector is after they are on'. The connector I5 is connected to a source of electric current through the wire 35, and the amount of current supplied to the suit is controlled through a rheostat or other control unit placed in series with one of the conductors in the wire 35. In case the current for the suit is alternating, the control unit may, if weight permits, be a variable voltage transformer.

In manufacturing the form of the invention shown in Figs. 1 to '7 and described above, the various widths of heating tape 23, 42, 46 and 58 are made in continuous lengths on suitable looms, and the making up of the tapes and other fabrics into individual garments is done in substantially the same way as ordinary garments are made. This permits the garments to be made with a minimum of special equipment and also permits them to be made easily in various sizes in order to fit different people.

Another form of the invention is shown in Fig. 8 and consists of a bandage 66 made in substantially the same way as the tape illustrated in Figs. 4 to '7. At one end of the bandage the two wires 61 and G8 which are woven into it are connected together, and, at the other end of the bandage, the two wires 61 and 68 are connected to the two conductors 69 and H of an electric wire 12 .fastened to the bandage. In use, the bandage is wound around a limb or other por-. tion of the body which is to be kept warm, and the electric wire 12 is connected to 'a suitable source of electric current through a conventional control unit, such as a. rheostat.

Another form of the invention is shown in Fig. 9 and consists of a blanket I4 provided with a series of wires 15 woven into the blanket in long parallel zones extending from one edge of the blanket to the other. Each wire 15 extends along the zone which it occupies in short steps at either side of the zone, the successive short steps being joined by relatively long runs across the zone. Thus the arrangement of each wire 15 is substantially the same as the arrangement of the wires 29 in the tape illustrated in Figs. 4 to 7. The wires 15 arranged in this way will provide the desired heating capacity without making the blanket stiff. The blanket will be flexible in a direction along the length of the zones occupied by the wires 15 because there are several inchm of wire in each inch along the zone, and the blanket will be flexible in a direction transverse on the zones because the successive zones are separated by flexible spaces in which there are no wires. I

The ends of the wires 15 are connected to flexible conductors l6 and 11 which extend along the edges of the blanket and which are connected at one corner of the blanket to an electric wire 18. The electric wire 18 may lead to a conventional manual or automatic control unit through which the amount of current flowing in the blanket maybe regulated.

Another form of the invention, shown in Fig. 10, is a heating pad 8i formed of two layers of fabric 82 and 83 between which is located a heating tape 84. The tape 84 is of the same construction as the tape illustrated in detail in Figs. 4 to 7, and the wires 85 which it contains are connected to an electric wire 88 leading from one corner of the pad. The tape M is looped back and forth between the two layers 82 and 83 of the pad in such a manner as to substan tially cover the area of the pad, as shown in the drawings. This construction is especially advantageous for a heating pad because it permits pads of various sizes to be readily made from a single size of tape at, the tape in large pads being arranged in two or more strips connected to the electric wire 86 in parallel. This construction may also be used for a blanket.

It may be pointed out that, in each of the different forms of the invention, special advantages flow from my novel construction. Because the wires in each tape in the flying suit are each several times as long as the tape itself, the wires in the several tapes can be all connected in parallel and still operate properly with the voltage available in a conventional airplane, and, with the wires in parallel, only one or two of them will be damaged by accidental localdamage to the suit. In every form of the invention, the close spacing of the wire permits the desired heating effect to be secured with the wire heated to a low temperature; this, in turn, permits the use of wire which is insulated simply by a coat of enamel and a cotton covering; and this simple insulation permits the garment, bandage, blanket, or heating pad to be washed without damage. In the case of the heating pad, as well as the other forms of the invention, the simple insulation permits the article to be folded, if desired,

' as contrasted to conventional heating pads having asbestos insulation, which is damaged by folding of the pad.

While I have shown and in other ways which will the person skilled in the art. Other variations than those shown may also be made. For example, the two wires 29 in the tape may be separated and located over alternate picks of the warp 28, one wire may be larger than the other to provide more heat, and the two wires may beconnected to the source 01' current through switches which will permit current to flow through either one or both wires in accordance with the amount of heat desired. Instead of the wires in each tape in the flying suit being double, there may be more than two, and the same variation may be made in'the other forms of the invention. The number of layers in the garment may be reduced, as by sewing the tape directly to the lining, which then becomes the foundation of the garment, and providing only a single layer of warm cloth outside of this. My invention, therefore, is not limited to the specific constructions which I have shown and described, but includes any construction falling within the terms of any one or more I claim as my invention:

suggest themselves to may be only one or there of the following claims.

1. An electrically heated jacket comprising a foundation jacket with sleeves, a pair of conductors extending around the jacket near the lower edge thereof, a plurality of wide tapes extending side by side over the shoulders and down to said conductors, and a plurality of narrow tapes extending each in a loop up one side of theviacket and down the sleeve, each of said tapes having an-electric wire woven therein, the electric wire extending along the tape by short steps Joined by relatively long runs across the tape and having its ends connected to the conductors, the narrow tapes being longerthan the wide tapes and the runs of the wires across the wide tapes being proportionately longer than the runs of the wires across the narrow tapes whereby the lengths of wire in the different tapes is substanductors secured to said fabric in spaced elation a.)

over the extent of said garment, the conductors for each tape comprising two fine wires separately insulated and extending continuously back and forth across said tape contiguous to each other and in substantially parallel relation throughout the length of the corresponding tapes, whereby said garment will have maximum flexibility, said conductors being connected to said leads in parallel, one end of eachconductor being secured to one lead and the other endto the other lead whereby the conductors in said tapes are connected in parallel, said tapes being secured on said garment in. such lengths that the electrical resistance of the conductors in the tapes will be substantially equal,

3. An electricallyheated textile member comprising a flexible foundation fabric, narrow elongated tapes of woven material secured to said fabric in spaced relation by stitching the side edges thereto, a pair of fine wire conductors insulated from each other woven into said tape, each pair as a weft threadv extending from said to side of said band throughout the length thereof whereby said tape has a maximum of flexibility, the margin of said tape being free of said conductors.

4. A flexible heating element comprising a woven fabric having a textile weft, an electrically conducting weft, and a textile warp, the electrically conducting weft lying over the textile weft and being separated therefrom and secured thereto by the warp, whereby said textile. weft constitutes an insulation for said electrically conducting weft when the latter is turned inwardly in use.

5. A flexible heating element comprising a long narrow tape of textile material having a continuous electric conductor woven therein and extending back and forth crosswise of the tape throughout substantially the length thereof,

said conductor consisting of a plurality of fine wires separately insulated and substantially parallel.

6. A flexible heating element comprising'a narrow elongated woven tape having a textile warp, a textile weft, and an electrically conducting weft, the electrically conducting weft lying over the textile weft throughout its entire length, certain warp threads lying between the electrically conducting weft and the textile weft, other warp threads lying over the electrically conducting-weft, and each pick of the electrically conducting weft terminating short -of both edges of the tape.

7. An electrically heated garment comprising a foundation portion constructed and arranged to be worn on the body, and a plurality of lengths of narrow tape secured to the surface of said foundation portion in side by side relation, each of said lengths of tape having an electric fine wire woven therein, the length and widths of said tapes being such that the electrical resistances of the wire therein will be substantially the same.

8. An electrically heated jacket comprising a foundation jacket, a pair of conductors extending around the jacket near the lower edge thereof, and a plurality of narrow elongated tapes extending side by side 'over the shoulders and down to said conductors, each of said tapes having an electric wire woven therein and con- ,nected at its ends to said conductors, the electrical resistance of said wires being substan tially the same in all of said tapes.

9. A pair of electrically heated trousers comprising a foundation pair of trousers, a pair of conductors extending around the upper portion of the trousers, one around each leg portion, and a plurality'of narrow tapes extending each in a loop .down a leg of the trousers, each of saidgtapes having an electric wire woven therein, each electric wire extending along its tape by short steps joined by relatively long runs across the tape and having its ends connected to the conductors.

\ 10. A pair of electrically heated trousers comprising a foundation pair of trousers, a pair of conductors extending around the upper portion of the trousers, and a plurality of tapes extending each in a loop down a leg of the trousers, each of ,said tapes having an electric wire woven thereinand connected at its ends to said conductors in parallel.

11. An electrically heated garment comprising a foundation portion constructed andarranged to be worn on the body, a plurality of narrow woven tapes secured to said garment extending over at least a portion of the area of said foundation portion, each tape having textile warp threads and a pair-of fine wire conductors separately insulated and together constituting a weft thread of said tape, and means for alternatively connecting either or both of said wires to -a source of electric current.

WALTER. JACOBSEN.

Referenced by
Citing PatentFiling datePublication dateApplicantTitle
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Classifications
U.S. Classification219/211, 219/539, 219/527, 126/204, 607/108, 219/528
International ClassificationH05B3/34
Cooperative ClassificationH05B3/342, H05B2203/017, H05B2203/036, H05B2203/015
European ClassificationH05B3/34B