US2564193A - Apparatus for shaping the ends of can bodies - Google Patents

Description

Aug. l4, 1951 M. R. DELAVAL, BORN CUlZAT APPARATUS FOR SHAPING THE ENDS OF CAN BODIES Original Filed May 15, 1945 Hll Patented Aug. 14, 1951 APPARATUS FOR SHAPING THE ENDS F CAN Booms Marie Rene Dela-val, born .Cuizat, Paris, France, assignor to Societe Civile dEtude des Brevets Valac, Paris, France, a corporation of France Original application May 15, 1945, Serial No. 593,842. Divided and this application May 23, 1949, Serial No. 95,143.v In France March 28,

Section 1, Public Law 690, August 8, 1946 Patent'expires March 28, 1964 3 claims. (01. 153-48) This application is a division of my co-pendin application Serial No. 593,842, filed May 15, 1945.

for Metallic Box, which application is now abandoned.

Metallic boxes or cans and more particularly cans of cylindrical shape are already known which comprise a removable stamped lid forced into and fitting a collar applied and secured onto the upper part of the can body, thus forming a hermetic closure for the can while permitting one to use the latter again after it has been emptied.

On the other hand, metallic boxes or cans are known, the body of which is stamped out of a single piece. Such cans offer certain advantages as regards their manufacture and use but they do not lend themselves to a direct application of aforced hermetically closing lid. I

The present invention has for its object a device for the manufacture of a metallic can or cylinder comprising a body preferably stamped out of a single piece without any connections or stamped out and provided at its upper end with a ring crimped unto the body so as to allow a hermetic closure by means of a stamped lid secured by forcing. v

The provision of a reinforcing ring in the upper part of a stamped can body through rolling and turning down the rim of the said can as described above constitutes in itself a technical problem the solution of which does not seem to have been taken into consideration hitherto.

The process used for the manufacture of metal r cans bounded by a cylindrical wall with an outside reinforcing ring with the device according to this invention, consists in forming a bead around the rim of the opening by rolling the outwardly and then forcing the adjacent wall carrying the bead parallel to the main wall of the can so as to maintain the bead in close contact with the outer surface of the can wall. 7 r

The device for carrying out this process, comprises a die and a punch axiallymova'ble-with respect to the die to force a can against the die,

said die being provided with an annular groove comprising an inner part of large radius curvature and an outer part of small radius curvature merging into a straight wall which groove pro-= duces first the rolling up of the rim into a bead and then the forcing of the adjacent wall carrying the bead parallel the main wall of the can under the action of the displacement of the punch.

According to another feature of the invention the die comprises a compressible core such as a core made of two parts which can slide with respect to one another against the action of a spri and onto which the body of the can is applied. The punch is then a hollow punch fitting onto the core of the die.

A form of execution of the above mentioned device is shown by way of non-limitative example in the appended drawing in correlation with a form of execution of the reinforcing ring which is also given by way of non-limitative example. In this drawing:

Figure l is an elevational view of a box or can made with the device according to the invention with its lid, the latter being shown separated from the body of the can.

Figure 2 is a sectional view of the rim of the can on a larger scale.

Figure 3 is a sectional View of a can body provided with a reinforcing rim formed on a separate collar which is fastened to the body through a crimping operation.

Figure 4 is a sectional axial vertical view of the device according to the invention and Figure 5 is a sectional view of the groove of the said device on a larger scale.

In the example shown in Figure 1, I represents the body of the box or can which is stamped out of a single piece and comprises a reinforcing ring 2 in its upper part. The lid 3 of the can is a stamped cover of an usual type in the rolled rim of which is provided a notch 4 into which either a coin or a screwdriver can be introduced for opening the box or can.

As may be clearly seen from Figure 2 the reinforcing ring 2 is obtained by turning down the upper rim of the can body on the outside of the latter. This turned down part offers a profile having the shape of an inverted U and terminates in its lower part in a circular rolled part 0r bead 5 bearing against the wall of the can body, thus insuring a high rigidity.

Figure 3 shows the case of a can of large dimensions the body 6 of which is provided in its upper part with a collar 1 separately applied and fastened through a crimping of the part 8 and comprising a reinforcing ring 2 such as described hereabove.

The device which is used for forming the reinforcing ring 2 on a can body such as shown in Figures 1 and 2 comprises, in the form in which it is shown in Figure 4, a die 9 secured by means of screws II] on a die-holder II resting on the Working table of the stamping press. The said die comprises a cylindrical central core I2 the outer diameter of which corresponds to the inner diameter of the can body under consideration and an annular groove I3 around the said core, The groove I3 (see Figure 5) has a U-shaped profile comprising a rectilinear part I3a forming for a short distance an extension of the generatrix of the core I2 and followed by a curvilinear part I3b having a comparatively great radius of curvature and connected by'a concave conge I30 having a smaller radius of curvature with a rectilinear part I3d parallel to the generatrix of the core I2. The depth of the said groove can vary according to the depth which it is desired to give to the reinforcing ring of the can body.

The core I2 is extended upwards by a sliding core I4 the upper part I ia of which has a diameter which is equal to the diameter of the core I2, i. e. equal to the inner diameter of the can body to be machined or worked upon and the top Mb of which is provided with a hollow having a shape corresponding to that of the bottom of the can body. In its lower part the sliding core I4 comprises a cylindrical tench i ic having a reduced diameter and slidingly fitting a bore I2-a provided in the central core i2 of the die 9 and, furthermore, guided and retained in the latter by an axial rod i5 screwed into the core Id.

:Finally, the latter is provided with a middle part led the diameter of which is smaller than that of the upper part Mia and around which a coil spring It is arranged which rests, on one hand, onto the core I2 of the die and, on the other hand, on a shoulder Hie of the upper part This coil spring, the outer diameter of which is slightly smaller than the inner diameter of the can body is preferably constituted by a wire of square section rounded towards the inside. The length of said spring, when not compressed, is such that the distance between the top I ib of the sliding core and the beginning of the groove I3 in the die 9 is substantially equal to the height of the stamped can body before the formation of the reinforcing ring according to the invention and the play left between the lower part of the tenon I40 and the bottom of the bore Ilia, i. e. the stroke of the sliding core Id, is slightly greater than the total developed length of the reinforcing ring to be formed.

Cooperating with the die is a hollow punch II which can be secured to the tool-holder slide of the press and the inner diameter of which is substantially equal to the outer diameter of the can body. In the bottom of the said punch is provided a piece-driver la the lower face of which reproduces the bottom of the can.

The so constituted device works as follows:

The stamped can body (the height of which is, of course, chosen sufficiently great to make :it possible to form the desired reinforcing ring) is fitted onto the sliding core I i of the machine, whereafter the punch I'a" is lowered. When the bottom of the can is clamped between the top I ib of the sliding core and the piece-driver I8 the lowering of the punch determines a corresponding lowering of the can body and, accordingly, the insertion of the free edge of the wall of the latter into the groove I3of the die. On arriving against the curvilinear part I3b the said wall is widened out and then it is rolled upon.

itself in the bottom I30 of said groove, thus forming the bead 5 of the reinforcing ring (see Figure 2). When the punch II continues its lowering movementthis rolled part is driven upwards, in the groove I3 along the body of the can and the reinforcing ring is thus formed until the punch has reached the lower part of its stroke. The punch I1 is then raised again and the piecedriver I8 insures the expelling of the can.

In order to insure a suitable formation of the reinforcing ring, .the inner surface of the groove I3 should be hardened, rectified and carefully polished.

WhatI claim is:

1. In apparatus for shaping the upper end of a can body to provide thereon an outwardly spaced, annular .re-enforcing ring, terminating at its free edge in a rolled bead which lies within said ring and spaces the latter in parallel relation to the adjacent wall of the can body, a die member having a central core surrounded by an annular groove, the cross sectional contour of the bottom of the grooves being of compound curvature, starting with an outwardly directed portion, with a radius of relatively .large curvature, followed by an upwardly directed portion with a radius of smaller curvature, said curved portions being disposed and connected in a manner to provide a smooth curved die surface and their oppositeends respectively terminating in parallel vertical portions which extend tangentially with respect to said ends of the curved portions.

2. In apparatus for shaping the upper end of a can body to provide thereon an outwardly spaced, annular re-enforcing ring, terminating at its free edge in a rolled head which lies within said ring and spaces the latter in parallel relation to the adjacent wall of the can body; a stationary die having an .upstanding central core for supporting a can body, a hollow punch relatively movable with respect to said die and adapted to fit over said core and can body, an annular shaping groove in said die surrounding the base of said core for receiving the edge of the can body to be shaped, the cross sectional contour of the .bottom'of said groove being of compound curvature, starting with an outwardly directed portion with :a radius-of relatively large curvature, followed by an upwardly directed portion with a radius of smaller curvature, saidcurved portions being disposed and connected in a manner to provide a smooth curved die surface and their opposite .ends respectively terminating in parallel vertical portions which extend tangentially with respect to said ends of the curved portions, whereby, when the edge of the can body is forced into said groove, a bead is rolled up and then forced upwardly in the. groove with a portion of the body of the canto provide a parallel, spaced reenforcing ring.

3. In apparatus for shaping the upper end of .a can 'body'to .provide thereon an outwardly spaced, annular re-enforcing ring, terminating at its free edge in a rolled bead which lies within said ring and spaces the latter .in parallel relationito the adjacent wall of the can body; a, stationary die having an upstanding central core for support- .ing a can body, a hollow punch relatively movable with respect to said die and adapted to fit first forming-a vertical continuation of the surface of the base of the core, then being directed outwardly on a radius of relatively large curvature, followed by an upwardly directed portion,

curved on a smaller radius and terminating in a vertical position lying parallel and in spaced relation to the vertical continuation of said core, said vertical portions extending tangentially with respect to the outer ends of the curved portions and said curved portions being disposed and connected in a manner to provide a smooth curved die surface, whereby, when the edge of the can body is forced into said groove, a head is rolled up and then forced upwardly in the groove with a portion of the body of the can to provide a parallel, spaced re-enforcing ring.

MARIE RENEE DELAVAL, BORN CUIZAT.

6 REFERENCES CITED The following references are of record in the file of this patent:

Number UNITED STATES PATENTS

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