US2073259A - Electric soldering iron - Google Patents

Description

l.. F. YOUNG ELECTRIC SOLDERING IRON 2@ 2i @1795. ummlmlmulm 11-'.

Filed June 20, 19.34

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INVENTOR Zeonanfzzzzg. I

hip ATTORNEY Patented Mar. 9, 1937 UNITED STATES PATENT OFFICE 8 Claims.

The present invention relates to electric heating devices in general, and particularly to what is known as electric soldering iron, and the like.

The principal objects of the present invention 5 are to provide a highly efilcient, inexpensively fabricable device of this kind in which the most important part, the heating element is so constructed as to combine simplicity of structure, eiciency in operation, and inexpensiveness in l manufacture, as well as ready exchangeability when required.

A further object of this invention is to provide a heating member in which the heating element or resistance is hermetically sealed against oxil dation within a hollow casing of highly heatconductive material, and in which the element is tightly packed by a high heat-conductive, pourable, crystalline or amorphous dielectric, adapted to maintain the windings of the element in de- 20 sired position within the casing.

A still further object of this invention is to provide within the heating member a suitable element support, by means of which the element may be suspended within the casing in a plural- 25 ity of courses, so as to provide the maximum radiating surface possible, distributed in the most uniform relation in respect to the casing.

Still another object of this invention is to provide terminals for the element, adapted to extend 30 from the sealed casing and equipped with frictional means, designed to engage the element support in such a way as to maintain the element in its desired expanded position until the powderformed dielectric completely fills all available 35 space within the casing so that each portion oi the element is tightly packed, supported and reinforced by the dielectric; the terminals are also instrumental in holding the element support in a floating position Within the casing, until packed 40 tightly in place by the dielectric.

A still further object of this invention is to provide in conjunction with the heating member an outer housing made of one piece of material and having two portions of varying diame- 45 ters, the housing portion of the larger diameter adapted to receive said heating member and iurther adapted to provide air circulation between the heating member and the housing, whereby the housing is kept relatively cool, thus prevent- 50 ing injury to the handle of the device.

A further object of this invention is to provide for the leads, extending from the heating member, a suitable insulator having throughpassages which terminate in channel formations,

55 said passages adapted to accommodate the greater part of the leads, while said channel formations are intended to receive the bent-over connections between the lead ends and exterior electric conductors entering the handle of the device.

A still further object of this invention is to provide in conjunction with the housing portion of the smaller diameter a dielectric handle, having the added property of not being heat conductive, said handle provided with a' depression for receiving attaching means, adapted to engage the smaller housing portion, said depressions being of sufficient depth to receive said attaching means in such a way as to preclude contact therewith, while the handle is being held.

The foregoing and a great many other objects and advantages of this invention will become more fully apparent from the ensuing description, in connection with the accompanying drawing, which latter, although forming a part of this invention, are not intended to limit the same to the actual showing, and in which Fig. l is a longitudinal cross-sectional View through one form of the present invention,

Fig. 2 is an enlarged longitudinal cross-sectional view of the heating member portion of the device,

Fig. 3 is a perspective View, partially in section of an assembly, comprising the heating element, the element support and the terminal or lead insulator,

Fig. 4 is an enlarged end View of the element support, showing the element suspended therein, as observed in the direction of lines ll--ll of Figure 3,

Fig. 5 is a cross-sectional View through the terminal insulator, taken on lines A5--5 of Figure l, and showing the channel formations,

Fig. 6 is a longitudinal cross-sectional View of the element casing,

Fig. 7 is a longitudinal cross-sectional View through the outer housing of this device,

Fig. 8 illustrates the heating element in its original close, helical form, with the terminals or leads attached,

Fig. 9 illustrates a diagrammatical View of the expanded element as it would appear when borne by the support,

Fig. 10 illustrates a miniature melting pot, as one of the exchangeable tools heatable by the device, and

Figs. 11 and l2 are cross-sectional views through modined heating members, terminating in miniature melting pots, and

Fig. 13 is an enlarged end View of a modified form of an element support.

Referring now specifically to the figures,

numeral In denotes the outer housing of the device, made preferably of one piece of tubing, and consisting of a portion I having a larger diameter and a portion I2 of a smaller diameter. At the end of the larger portion there are provided apertures I 3 for receiving element casing attaching means, while at the housing portion of the smaller diameter there will be noted an aperture Ill adapted to receive attaching means I 5 imbedded in depression IE of handle I'I. (See Fig. 1.) The larger housing portion is secured by rivets or screws I8, passed through openings I3 into suitable holes provided in enlargement or head I 9 of the element casing 20. The latter consists of a hollow cylinder, open at one end and closed by the head formation IS, within which latter is provided a threaded socket 2i for receiving, and conductively connecting therewith a heatable tool, as for instance a tip 22 or a melting pot 23, such as illustrated in Figure 10. Obviously any other heatable tool may be inserted and heat-conductively connected with head I9, since the tools are intended to be exchangeable in this construction.

Adjacent to the closed head portion of the casing there is provided an insulator disc 24, such as mica, the purpose of which will be explained presently. Into the casing there is inserted an element support 25, consisting of a cylinder made of dielectric material and provided with a plurality of through-passages 25, which are preferably cylindrical in form. A heating element 27, originally comprising a close helix, as shown in Figure 8, is connected at its two ends 28 to leads or terminals 29. The portion of the terminals, immediately adjacent to their connections with the element, are curved in a wave-like form, as seen at 30, so as to frictionally engage the interior of two passages provided in the element support. In Figures 3 and 4 the element support is'shown to have four such through-passages, and the element is in engagement with all four of them.

vIn this construction the insertion of the element is accomplished as follows: Both terminals, to which the ends of the element are attached, are first passed through two of the passages and then returned through the two other passages. By these successive operations the originally close helix is stretched so that each winding of the helix is separated from the other. The wavelike ends of the terminals frictionally engage the walls of their respective passages and thus hold the element in its stretched position within the support. While being held by the terminals, the support with the stretched element therein, is inserted into the casing so that the portions 3l of the element, shown clearly in Figure 9, bear against insulating disc 2li rst inserted into the casing. Element support 25 is now held equally spaced from the interior wall of the casing, so as to assume a oating position therewithin. VNow all available space within the through-passages and between the individual windings of the element, and between the element support and the casing is completely lled and tightly packed by a pourable, sand-like or amorphous dielectric indicated at 32. While the process of packing the dielectric into the casing is taking place, the frictional engagement of the wave-like formation of the terminals with the through-passages of the element support prevents a displacement of the element windings within the support.

It will be observed that the element casing is somewhat longer than the element support, so that the latter is completely housed, and is capable of being hermetically sealed therewithin. The seal is clearly indicated at 33. It consists of a heat resisting dielectric substance which will readily adhere to the metallic surfaces of the casing and of the terminals, and which has the same coefficient of expansion as that of the metal.

Adjacent to seal 33, and extending therefrom through the reduced portion I2 of the housing, and beyond the housing into handle I1, there will be observed a terminal or lead insulator 36, comprising a cylindrical structure with two through-passages 35, which latter terminate into channel formations 36. These channel formations are adapted to receive the connections between the terminals and the exterior electric conductors 37 entering the outer end of handle I 'i'. The connection between the terminals and these conductors is preferably accomplished in the following manner: The ends of the terminals are passed through passages 35 and bent over and out at right angles to the channel formations. The ends of the electric conductors are bent in similar way and then the terminals and the conductors are twisted together in the approved fashion and either soldered or welded together; now the connections are bent backwards, in the direction indicated by the arrow in Figure 3, and clearly seen in their final position in Figure l. The channels completely house these connections, insulate them, and prevent undesired bulkiness usually found in similar devices. These connections also decidedly reduce the cost of the device, in that screw attachments or similar wire connecting means are successfully eliminated thereby, thus greatly simplifying production. The arrangement of the element casing and of the insulator for the terminals within the outer housing provides a very beneficial air space so that air circulation Within the housing and the handle may be provided. In order to promote circulation suitable air holes 38 may be arranged in the larger housing portion adjacent to the element housing. There is sufficient air space provided within the handle for cold air to enter therein, whereas hot air may be dispelled through L.

aperture 38.

Referring now to the modified forms of the element housing shown in Figures 11 and 12, the latter are primarily intended for use in connection with heating devices where the heating tools i is to be permanently attached to, or is to be integral with the heating member. In Figure 11 is shown a miniature melting pot 39 provided with a tubular extension 40, adapted to serve as element casing of the device, and is provided with a stepped-up connecting enlargement 6I to which housing 2 is secured in similar manner as shown in Figure l.

When it is desired that more intense heat be supplied to the pot formation, the position of the element casing may be changed, as proposed in Figure 12. In this figure the element casing 43 extends below the bottom of melting pot Gd. In all other respects the construction of the element casing and its attaching provisions to the housing is the same as in Figures 1 and 1l.

In Figure 13 there is illustrated an element support 25', provided with two through-passages 45, and with two outwardly open channels 4t, corresponding to the two other through-passages of the support shown in Figure 4. This modified construction of the element support possesses the advantage of facilitating a more ready .attachment of the element thereto, permits a better distribution of its expanded windings, and promotes more direct heat radiation from those parts of the element which are held in the chan-- nels.

From the foregoing description of the few specific forms of the present invention it becomes evident that a good many variations may be provided in order to enhance the quality of, and to adapt the device for various specic purposes and uses.

Due to the compact and simple arrangement of the sealed heating member, the latter may be readily exchanged, in which case its attaching provisions to the outer housing will require some slight alterations. In any modied form, however, there is always provided sufficient air space between the element casing and the housing, so as to promote air circulation and cooling of the housing, tonot only preserve the handle, but also to maintain a perfect connection between the handle and the smaller housing portion secured thereto.

While I am aware of the existence of heating devices, designed to serve similar purposes to that oi the present invention, l do not know, to the best of my knowledge, of any devices employing the principles of construction described above, and having in mind the possible necessity of varying the details of the construction illustrated, I herewith reserve for myself the right to modify, and improve thereupon, without departing from the broad scope of my idea, as set forth in the annexed claims.

I claim:

l. In an electric heating device, the combination with a tubular, one-piece outer housing, having two portions of different diameters, of an element casing disposed partially within and secured to the housing portion of larger diameter, said casing comprising an integral, hollow cylindrical member, made of heat conductive material, and provided with an enlarged, closed end extending beyond, and in engagement with said larger housing portion, and including means for removably attaching a heatable tool thereto; the other, or inner end of said casing being open, a heating element within said casing, hermetica-lly sealing and terminal holding means provided at the open end of said casing; an insulating element within, and next to the enlarged end of said casing, a pair of heating element terminals secured within, and extending from said sealing and terminal holding means, an insulator for said terminals, extending from said casing into the housing portion of the smaller diameter, and provided with interior passag-es and end channels, the latter serving for accommodating the connections between the terminals and exterior electric conductors.

2. In an electric heating device, as set forth in claim l, a handle in engagement with the end of the housing portion of the lesser diameter, and means imbedded in said handle for retaining the latter and said housing portion at desired relation to one another.

3. In a heating device, the combination with a tubular, one piece housing having one portion of a smaller, and another portion oi a larger diameter, of an integral, tubular element casing having a reduced, inner open end and an enlarged, outer closed end, said closed end provided with means for accommodating and holding a heatable tool, said closed end secured to, but distanced from the end of the housing portion of the larger diameter, an insulating member disposed within, and next to the enlarged end of said casing, a heating element within said casing, hermetically sealing and terminal supporting closing means at the inner or open end of the casing, terminals extending from said closing means, an insulator extending from said casing into and beyond the housing portion of the smaller diameter and provided with a pair of through-passages for receiving said terminals, these passages ending in channel formations, the ends of the terminals extending into said channel formations and being connected with external electric conductors, their connections being bent back and secured in said channel formations, a handle in engagement with the housing portion of the smaller diameter and extending over said insulator, and attaching means connecting said housing with the handle, arranged within the handle material and below its outer surface, so as to preclude contact therewith.

4. An electric heating device comprising an outer housing having enlarged and reduced portions, a one-piece heating element casing within the enlarged housing portion and provided with a closed, enlarged end, forming an integral part of the casing, said enlarged end extending beyond said housing portion, the other end of said casing being open, a pair of undulated terminals in rictional engagement with the interior of, and extending from said casing, hermetic sealing means provided at the open end of the casing and immovably holding said undulated terminals by way of their undulations.

5. An electric heating device comprising an outer housing having enlarged and reduced portions, a one-piece heating element casing associated with, disposed within and spaced from said enlarged housing portion, said casing having at one end a closed head provided with a recessed portion to which the housing is secured, the unrecessed part of the head extending beyond the housing and forming one end of the device, the closed head forming an integral part of said casing, the other end of said casing being open, a pair of undulated terminals in frictional engagement with the interior, and extending from the open end of said casing, hermetic sealing means provided at the open casing end and immovably holding said undulated terminals against disengagement from said casing by way of their end undulations.

6. An electric heating device as per claim 5, a dielectric terminal guide disposed within and extending beyond the reduced housing portion and provided at its outer end with longitudinally arranged means for accommodating twisted connections between said terminals and exterior electric conductors.

'7. An electric device as per claim 5, a dielecn tric terminal guide disposed partially within and extending beyond the reduced housing portion and provided with through passages terminating in enlarged, longitudinally arranged channel portions for accommodating the twisted connections between said terminals and exterior electric conductors, and a hollow handle associated with the reduced housing portion and so arranged as to accommodate the extending end of said terminal guide.

8. An electric device as per claim 5, a one-piece substantially cylindrical dielectric terminal guide extending from said hermetic sealing means of said casing throughout and beyond the reduced housing portion, and provided with a pair of through passages terminating at the outer end of the guide in channel formations for accom- Cil modating the twisted connections between said terminals and exterior electric conductors, said channel formations constituting longitudinally arranged continuations of said passages, a hollow handle associated with the end of the reduced housing portion and accommodating the channeled end of said guide, and handle attaching means in engagement with the reduced housing portion, and disposed within the handle material and below the outer surface, for precluding contact therewith.

LEONARD P. YOUNG.

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