US1839674A - Interlocking stovepipe seam - Google Patents

Description

Jan. 5, 1932. HAYMAN 1,839,674

-INTERLOCKING STOVEPIPE SEAM Filed March 20, 1930 6 4 5 6a 9 lizveni'or:

56 97 I Jia yman,

- MMDWWM Patented Jan. 5, 1932 PATENT; OFFICE EBER J. HAYMAN, OF PARKERSBURG, WEST VIRGINIA INTERLOCKING STOVEPIPE SEAM Application filed March 20, 1930. Serial N0. 437,417.

My present invention relates to improvements in interlocking means for the edges of sheet-metal stovepipes or the like. An object of the invention is to provide an interlocking seam for stovepipes which is readily snapped into secure and permanent interlocking connection with a minimum of effort and labor and a maximum of security of connection and strength.

A. further object is to provide an improved seam of reinforced construction which is of such strength as to prevent accidental separation thereof without the necessity of clamping or hammering the folds together and without the use of rivets.

Other objects will appear hereinafter.

The invention consists in the features, combination, and arrangement of parts hereinafter described and particularly pointed out in the appended claims.

In the drawings,

Figure 1 is a cross sectional view of a sheet metal stove-pipe embodying my invention in position prior to being snapped into pipe form. I

Fig. 2 is a similar view of the parts in interlocking connection.

Fig. 3 shows diagrammatically the successive steps performed upon themale section as by means of dies.

Fig. 4 shows diagrammatically the successive steps performed upon the female section as by means of dies Fig. 5 is a perspective view showing the manner in which the stove pipe lock may be opened after it has been locked.

Fig. 6 is a view of a joint according to my invention, which has been hammere Referring to the drawings, 1 represents the metallic sheet from which the pipe section is formed. This sheet is bent transversely to generally cylindricalshape. One marginal edge is bent inwardly upon itself as shown at 2 and then outwardly as shown at 3, the outwardly bent portion 3 extending beyond the reverse bend to form tongue 4. The. fold between 2 and 3 forms an inwardly facing locking shoulder 8. This comprises the male portion of the joint.

The other marginal edge of said metallic sheet is pr-ovided with a female formation comprismg an inwardly folded portion 5 and an outwardly folded portion 6 spaced from and providing a groove 7 with said inwardly folded portion 5 The outwardly folded portion 6 extends outwardly beyond the mouth of the groove 7. The portion 6 from a point adjacent and slightly within the mouth of the groove 7 is of double Wall thickness.

The double wall consists of a terminal fold 6a bent inwardly and lying against the surface of the outwardly folded portion 6. The folded outer or marginal edge of the double wall 6, 6a is bent upwardly and backwardly to provide a locking flange 9. The double wall 6, 6:; including the doubled locking flange 9 provides a substantial reinforcement for the joint which materially strengthens it, prevents crushing in transit and straightening out of the locking flange 9 under heat and lateral strain, and thus prevents accidental separation of the joint when in use.

In forming the joint the tongue 4 of the male member is inserted into the groove 7 and the locking edge 8 is snapped into interlocking engagement within the locking flange 9. The entire portion 3 of the male member including tongue 4 and edge 8 is then securely embraced within the pocket 10 defined by the shoulder 9 of the female member and including the groove 7 In Flgs. 3 and '4 are diagrammatically shown the effect upon the male and female sections respectively of the successive bending and folding operations to which they are subjected in their formation, as by means of dies. It will be obvious that some of these operations may be combined by suitable die arrangement, as for instance, the second and third operations in Fig. 4 may be combined and performed in one operation.

Fig. 5 shows the joint partially opened after having been closed or locked. In this separation operation, preferably the plain end C of the full joint pipe section is toward' the operator who, starting at the plain end, presses the seam A toward the opposite wall B of the pipe, with the wall B resting upon a flat surface thus causing the pipe to assume generally oval shape with the seam depressed.

In so doing the operator also exerts a separating strain on the lock which will begin to separate at the plain end. The -0 erator then shifts or pushes his hands and ngers along the joint toward the crimped endD of the pipe maintaining the inward pressure and separating strain which results in complete separation of the-joint. A convenient and effective manipulation of this joint consists in placing the four fingers of each hand adjacent the opposite sides of the seam as at E and F in Fig. 5, with the thumbs beneath the wall of the pipe as at G. The pressure and separating strain is then readily applied to result in separation as shown at the plaln end in Fig. 5, at which time the thumbs are removed from beneath the pipe wall and the fingers are pushed along toward the crimped end keeping up the pressure and separating strain. In this way complete separation 1s readily effected with a minimum of effort and time and at the same time the joint is so constructed that when quickly snapped into place it will be firmly locked.

It is desirable to provide a stovepipe joint which is capable of being hammered if desired, as some buyers are prejudiced in favor of a stovepipe joint which can be hammered. The-joint of the present invention possesses this advantage, since the parts are so formed that hammering does not destroy their eflicienoy nor impair the security of the lock. Folded shoulder 9 is so inclined and the space between portions 1 and 2 of the male portion is such that, if the joint is hammered, the fold 9 will be forced into and will be firmly imbedded in this space to make the hammered joint secure. This is shown in Flg. 6.

I claim:

1. In a stovepipe, a sheet of metal one marginal edge of which is provided with a male formation comprising an inwardly folded portion and an outwardly folded portion providing an inwardly disposed locking edge and a locking tongue, the other marginal edge of said metallic sheet being provided with a female formation comprising an inwardly folded portion and an outwardly folded portion spaced from and providing a groove with said inwardly folded portion, said outwardly folded portion extending outwardly beyond the mouth of the groove and having a locking flange at its outer end, said outwardly folded portion being of double walled thickness from and beyond a point adjacent the mouth of said groove, said tongue being receivable in said groove with said locking flange and locking edge in interlocking engagement.

2. A stovepipe according to claim 1 in which said double-walled thickness is ormed by a terminal fold portion folded inwardly from the top of said locking flange and ly-.

ing against the inner side of said flange and against the said extended outwardly folded portion, the inner edge of said terminal inward fold being disposed within the mouth of the groove.

3. An interlocking stovepipe seam comprising a male formation along one edge consisting of a reversely bent edge providing a locking'edge and a tongue, a female formation along the other edge consisting of a reversely bent edge providing spaced walls enclosinga groove and, extending beyond a point adjacent the mouth of the groove in double wall thickness, said double wall extension being bent to provide a terminal locking flange forming a pocket including said groove for receiving the tongue and locking edge of said male formation.

4. In a stovepipe, a sheet of metal one marginal edge of which is folded back upon itself .to lie against the outside of the sheet and to form a double wall, said sheet immediately inwardly of said double wall being doubled upon itself to form a groove adjacent said double wall, the marginal edge of said double wall being bent outwardly and backwardly to provide a doubled locking flange defining the marginal limit of a pocket including said groove, the other margin of said sheet being adapted to be inserted in said pocket and being-doubled upon itself Within the marginal edge to provide an inwardly disposed locking edge to engage the said doubled looking flange.

5. A stovepipe construction according to claim A in which the inner margin of said double wall is disposed slightly within the mouth of said groove formed by the sheet being doubled upon itself.

6. A stovepipe joint comprising a female formation along one edge consisting of a reversely bent edge providing spaced walls en closing a groove and extending beyond a point adjacent the mouth of the groove in double wall thickness, said double wall extension being bent to provide a terminal looking flange forming a pocket including said groove, a male formation along the other edge consisting of a reversely bent edge providing an inwardly facing locking edge and a tongue, said tongue lying in the said groove with the said locking flange and locking edge in engagement, said reversely bent male formation providing a space between its folded walls above its locking edge, and said locking flange being inclined with its edge in position to be forced into said space if the joint should be flattened as by hammering.

In testimony whereof, I aifix mysignature.

' EBER J. HAYMAN.

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