Gasket.

Application filed January 25,1913. Serial No. 744,111.

To ail whom, it may concern:

Be it known that I, Charles F. Hettinger, a citizen of the United States, residing at Camden, in the county of Cam5 den and State of New Jersey, have invented certain new and useful Improvements in Gaskets, of which the following is a specification.

This invention relates to gaskets for pre10 venting the escape of fluid under pressure.

The object of the invention is to provide a gasket so constructed that it . possesses great strength, is sufficiently elastic to permit of spreading without injury, is com15 pact and rigid, will not blow out or crush under extreme pressure, and is highly efficient in the performance of its function.

This invention involves the provision of a gasket, preferably of annular form, con20 sisting of a plurality of convolutions of a metallic strip and a strip of suitable packing material. Preferably the plurality of convolutions are formed by winding the metallic strip and the packing strip spirally. 25 In accordance with the invention, the metallic strip prior to being spiraled is curved transversely by bending it along lines extending lengthwise thereof, so as. to provide oil each convolution of the strip a por30 tion which projects laterally into coaction with the next adjacent convolution. Furthermore the coacting portions of adjacent convolutions are interlocked in such a manner that injurious spreading of adjacent 35 convolutions is effectively precluded. In the embodiment of the invention which I prefer to employ, the strip is curved transversely so as to provide a loop extending laterally from the body of the strip inter40 mediate the edges thereof such that when the strip is spiraled tha-loop on each convolution will telescofie with the loop of the next outer convolution, and these two telescoping portions are interlocked so as to 45 hold the two convolutions at the requisite distance apart. The portions of the strip lying on either side of the loop in the strip are curved transversely, as in this way they are made much more strong in resisting a 50 crushing strain. The packing material is wound spirally with the metallic strip in the -spaces between adjacent convolutions and on either side of the loop formed in the strip. This packing material preferably 55 projects a small amount beyond the planes of the edges of the metallic strip so as to provide pads of the packing material which coact with the surfaces between which the gasket is inserted. The efficiency of the gasket in preventing leakage is further in- eo creased by having the loop on the innermost spiral open to the interior of an annular gasket, so that the interior of this loop is in connection with the space within - which the fluid under pressure is confined. 65

In this way the pressure of the fluid is allowed to enter within the loop in the innermost spiral and tends to expand the walls of the loop so that the packing material is forced outwardly into more effec- 70 tive contact with the walls between which the gasket is inserted.

I have illustrated the preferred embodiment of my invention in the accompanying drawings, in which— 75

Figure 1 is a sectional view of a gasket constructed in accordance with the invention, in position between two flanges of a piece of mechanism, Fig. 2 is a perspective view of a piece of the gasket, Fig. 3 is a 80 view illustrating the method of shaping the metallic strip, Fig. 4 is a sectional view of the gasket illustrating a slight modification, and Fig. 5 is a plan view of the complete gasket. 85

Referring to these drawings, Fig. 1 shows a gasket 6 in position between two flanges 7 of a container adapted to hold a fluid under pressure, such, for instance, as the cylinder of an engine or pump. The gasket 6 90 is inserted between the two flanges 7 and then those flanges are drawn together in hard cqntact with the gasket, and the latter must be able to sustain a great crushing strain and prevent escape of the liquid, even 95 though the pressure of the latter be very high. The gasket is of annular form and consists of a plurality of convolutions of metallic strip and a suitable non-me.tallic packing material, such, for instance, as an 100 asbestos composition. Preferably, the metallic strip is wound edgewise in the form of a spiral and the strip of packing is wound simultaneously with the metallic strip so that it lies in the spaces between 105 the adjacent convolutions of the metallic strip. Prior to winding the metallic strip spirally, this strip is bent along lines extending lengthwise thereof, so as to give it a transverse curvature necessary to provide 110

1.089,134 for a laterally extending projection adapted to make each revolution of the strip interlock with the adjacent convolution. The preferred manner of shaping the metallic 5 strip is shown in Fig. 3. A flat strip of sheet-metal, such as that shown at 8 in Fig. 3, is first bent to such cross-sectional shape as to provide two curved portions 9 lying one above the other and between them a loop io 10 projecting laterally from the body-portion of the strip. This having been done, a strip of the packing material 11 is laid upon each side of the loop or laterally projecting portion 10, with its side against the adja15 cent curved portion 9. The metallic strip thus shaped and having the strips of packing material thereon, is then wound spirally in such a wav that the concave side of the curved portions 9 of each succeeding con20 volution lies against the sides of the strips of packing 11 opposite those engaged by the convex surfaces of the curved portions 9 of the preceding convolution. When the strip is wound in this way, the lateral projection 25 or loop 10 of each convolution will enter within and telescope with the projection or loop 10 of the next succeeding convolution. At the time of spiraling the strip in this way, the. projection 10 of each convolution 30 is crimped or contracted at a point about midway of its length, as shown at 12, so as to provide depressions in the outer sides of the loop 10, into which the corners of the next adjacent convolution at the junction of 35 the- curved portions 9 and the loop 10 thereof may enter. In this way the two convolutions are interlocked in such a way that they will offer strong resistance to injurious spreading. If necessary, the two corners of 40 the strip at the junction of the loop and the two curved portions 9 thereof may be pressed together by suitable tools so that they will be carried well into the depressions formed in the sides of the loop 10, and 45 thus insure a proper interlocking of those parts.

In addition to the prevention of injurious spreading of the convolutions of a gasket by means of the interlock provided between 50 each pair of adjacent convolutions, the loop construction herein described involves a further important advantage. It will be seen that the loop in the innermost spiral is open to the interior of the gasket, so that the 55 fluid under pressure within the container may enter within this loop. The pressure of the fluid within this loop tends to expand the loop by forcing its walls apart, and as a result of this the strips of packing lying ad60 jacent to the walls of the loop are forced outwardly so that they are pressed into hard contact with the flanges 7 between which the gasket lies. Tn further preventing the escape of the fluid under pressure through 65 the spaces between the gasket and the flanges

7, I prefer to employ strips of packing material 11 of such size that they project slightly beyond the planes of the edges of the convolutions of the metallic strip. This is shown in Fig. 2, where the packing 11 is ₇₀shown as projecting beyond the edges of the metallic strip.'

Preferably, the ends of the spirally wound gasket are interlocked with the convolutions of the gasket in such a way as to ₇₅hold the parts in proper relative positions and at the same time provide for a slight amount of relative movement in order to allow for same spreading without injury. In some cases it may be desirable to leave go the ends of the metallic strip of a gasket loose, so that slight movement of the convolutions may take place. These ends may, however, be secured to the convolutions adjacent thereto in any suitable manner, as g₅for instance, by electric welding or soldering. Instead of securing the ends to the adjacent convolutions in this way, however, I may employ endless bands or rings, one within and one at the periphery of an an- 90 milar gasket, these bands being arranged to hold the adjacent end of the spirally wound metallic strip in position against the adjacent convolution of the strip. Such an endless band or ring is shown in Figs. 4 and 95 5, at 13, this band being made from a piece of· wire which is cut to the proper length and inserted in position within the opening in the gasket and having its ends welded together. In the present instance, the band too or ring 13 is shown as positioned by tlie depression formed at the opening leading to the interior of the loop 10, but it will be understood that such a ring or band as that shown in Figs. 4 and 5 may be employed in 105 connection with gaskets differing in construction from that here described, but involving the use of one or more spirally wound strips. A similar endless band or ring is shown at 14 located on the periphery 110 of the gasket. In this instance the ring 14 is shown as a thin strip of sheet-metal laid over the loop of the outermost convolution, the strip being curved so that it will remain in its proper position. u.-,

If desirable, the two faces of the gasket may be saturated with graphite or other suitable substance, to prevent the gasket from sticking to the flanges between which it lies, and when desired the surface of the 120 gasket may be waterproofed.

-A gasket constructed as herein illustrated and described is very effective in preventing the escape of fluid under pressure and at the same time it possesses such elastic strength 125 that,there is little or no danger of crushing· the spirals of the gasket, even though the gasket be subjected to extreme pressure in drawing the flanges 7 together upon the gasket. Furthermore, the danger of in- 130

1,089.134 with the next adjacent convolution, and non· 60 metallic material between adjacent convolutions on each side of the said laterally-extending portion, substantially, as set torth.

6. An annular gasket comprising the combination of a plurality of convolutions of 65 metallic strip, the strip of each, convolution having an integral looped portion intermediate the edges of the strip extending laterallv into co-action with the next adjacent convolution, and the looped portion of the 70 innermost convolution being in open communication with the interior of the annular gasket, and non-metallic material between adjacent convolutions on each side of the laterally extending portion connecting those 75 convolutions. . . ,. .

7. A. gasket comprising the combination of a plurality of convolutions, of metallic strip, the strip of each convolution having a body-portion and an integral portion intermediate the edges of the strip extending laterally from the body-portiofl and the laterally-extending portion of each convolution entering within the laterally extending portion of the next adjacent convolution, and 85 non-metallic material between adjacent convolutions on both sides of the laterally extending portion of one of the two adjacent convolutions, substantially as set forth.

8. A gasket comprising the combination 90 of a plurality of convolutions, of metallic strip, the strip of each convolution comprising a body-portion in two parts and an integral laterally-extending looped portion between the two parts of the body-portion, the 95 looped portions of the several convolutions being in engagement and forming a continuous body of metal through the gasket in the plane thereof, and non-metallic material between adjacent convolutions on both sides of 100 the looped portion extending ^bety^eeP.^thoseconvolutions, substantially as set forth.

9. A gasket comprising the combination of a nlurality of convolutions of metallic strip wound spirally on edge, said strip being curved transversely to provide two curved portions lying in substantially the same plane and between them a loop extending laterally from the remaining portion of th* strip, and packing materia! between ad- no jacent convolutions on both sides of said 'iXS^Xd witnessed this 18th

Witnesses:

Wm. J. Earnshaw, John B. Kilburn.

iurious spreading of the convolutions of the gasket is prevented by the provision of an integral projection on each convolution which coacts with the adjacent convolution 5 in such manner as to interlock therewith.

and thus hold the two convolutions at a predetermined distance apart This provision of lateral projections on the several convolutions not only affords an interlock, but 10 also provides the interior of an annular gasket with a groove into which the compressed fluid may enter so that it will tend to force the packing material, outwardly against the surfaces between which the gas15 ket lies. . . , , _T

Having described my invention, what 1 claim as new therein and desire to secure by