US3318203A

US3318203A - Apparatus for forming a rolled edge on containers made of sheet material

Info

Publication number: US3318203A
Application number: US478688A
Authority: US
Inventors: Durat Robert Georges Eugene
Original assignee: Individual
Current assignee: Individual
Priority date: 1965-04-27
Filing date: 1965-08-10
Publication date: 1967-05-09
Anticipated expiration: 1984-05-09
Also published as: FR87743E

Description

y 9, 1967 R. G E. DURAT 3,318,203

APPARATUSFOR FORMING A ROLLED EDGE ON CONTAINERS MADE OF SHEET MATERIAL Filed Aug. 10, 1965 mm k United States Patent 3,318,203 APPARATUS FOR FORMING A ROLLED EDGE ON CONTAINERS MADE OF SHEET MATERIAL Robert Georges Eugene Durat, J ouet-sur-lAubois, Cher, France Filed Aug. 10, 1965, Ser. No. 478,688 Claims priority, application France, Apr. 27, 1965, 14,779, Patent 87,743 7 Claims. (Cl. 93-36.5)

Devices are already known for forming rolled edges on containers made of sheet material, such devices comprising, on the one hand, a rolling tool consisting of a central part with a hollow quarter-torus shaped external throat thereon and of jaws which are mounted under slight friction on the support of said part, whereby to slide radially behind the latter, and which have a hollow half-torus shaped groove on their inner surfaces which forms a rolling die jointly with said throat, and, on the other hand, means for moving said tool axially toward the contanier mounted on a fixed coaxial support, whereby to cause its edge to be rolled down in said die, means for opening said jaws on completion of the rolled edge and means for reclosing them on recession of said tool from the container with its rolled edge.

Such a device is described in US. Patent application Ser. No. 428,324, filed by the applicant on Jan. 27, 1965.

The device according to the above-cited patent application will not permit the use of sheet material of any kind or thickness. Thus, when cardboard of a thickness exceeding a certain value is used for example, breaks occur along the rolled edge.

The present invention has for its object to widen the range of sheet material usable for forming rolled edges, and accordingly relates to an apparatus for forming rolled edges on sheet-material containers of the type hereinbefore specified, wherein said rolling tool is rotatable about its longitudinal axis relatively to the container, which container is coaxial therewith and mounted on a fixed support. In a preferred form of embodiment, the tool-carrier hereinabove specified is mounted in a hearing with a fixed external cage and is continuously rotated by any convenient means.

In accordance with the present invention, a rolling die as hereinabove disclosed is formed with splines with rounded corners and is preferably made of steel. The expansion which the cardboard undergoes when the rolled edge is being formed is no longer produced by pressure, as such, but by a periodic deformation of the fibers as they transit in rotation over the toroidal protrusions which said splines constitute.

t Preferably, the jaws forming part of the rolling die are locked when operating in the closed position, by means of a keeper-ring located between the hollow tool body and the slides described in the above-cited patent application, in two facing circular grooves formed in these members. Such locking is necessary in order to render the jaws immovable and prevent them from opening in response to the centrifugal force generated by the rotation of the apparatus.

Likewise in accordance with the invention, tool movement is controlled by a cam which is so contoured as to permit rapid approach of the tool toward the container, slow formation of the rolled edge thereon, rapid opening of the jaws and rapid return motion of the assembly.

The description which follows with reference to the acompanying non-limitative exemplary drawings will give a clear understanding of how the present invention can be carried into practice.

In the drawings:

FIG. 1 shows in longitudinal section the apparatus for forming rolled edges according to the present invention;

FIG. 2 is a front elevation view on an enlarged scale of the central part which, jointly with the jaws, forms the rolling die of FIG. 1;

FIG. 3 is a sectional view taken on the line IIIIII of FIG. 2; and

FIG. 4 is a fragmental the line IV-IV of FIG. 3.

Like in the above-cited patent application, the purpose of the apparatus shown in the accompanying drawings is to form a rolled edge on the opening 1 of a frustoconical container 2 open over its smaller base. This container is mounted in a fixed support 3 and centered thereon by a hollow frusto-conical part 4. The larger base of the container bears on a surface 5 consisting, say, of the thrust face of a tool used to complete the fitting of the container bottom.

The means for forming the rolled edge include a hollow tool-carrier 6 coaxial with the part 4 and rotatably mounted in a bearing 61 the outer cage of which is rigidly united with a fixed support 62 through the medium of a ring 63. At its end remote from the container 2, the toolcarrier 6 is equipped with a pulley 64 which is continuously rotated by a V-belt 65 driven by any convenient means. A key 66 rigid with the tool-carrier 6 is slidable in a longitudinal groove formed in the hollow tool body 12 and serves to transmit the rotation to the latter.

Like in said patent application, a hollow tool body 12 is slidably mounted in the hollow tool-carrier 6, and a shaft 15 is slidably mounted in this tool-body 12. Likewise to be found are the slides 17, the jaws 28 and the frusto-conical part 32, except that the latter, which is prefenably made of treated steel, has a hollow half-torus shaped throat 36 formed thereon, while the grooves 37 of jaws 38 which extend it are in this case shaped as a hollow quarter-torus. Further, the frusto-conical portion of the part 32, the throat 36 and the grooves 37 are formed with radial splines 67, all the corners of which are rounded as is clearly shown in FIGS. 2 and 4. In addition, the rotating motion is transmitted to the rolling die 32, 36- by means of two pegs 69 rigidly connected to the tool body 12, parallel to the axis thereof. These pegs extend through oblong openings 70 formed in two of the diametrically opposed slides 17 and penetrate into blind holes 71 formed in the frusto-conical part 32.

In order to prevent the jaws 28 from loosening responsively to centrifugal force when they are operative in the closed position, a keeper-ring 68 made of spring wire is fitted between the hollow tool body 12 and the slides 17, in facing circular grooves formed in the tool body and the slides respectively.

In order to achieve the axial displacement of the rolling tool required to move the rolling die toward and away from the container 2, a bearing 72 gripped between two nuts 44 and 45 is mounted on the threaded end 43 of the shaft 15. The outer cage of this hearing is rigid with a part 73 to which is pivotally connected a link. 74 the other end of which is in turn pivotally connected to a beamlever 75. The latter is fixedly fulcrumed about a point 76 and its other arm bears a follower 77 which is urged against a cam 78 by a spring 79 connected across the beam-lever and the fixed support 62.

The distance of the contour of the cam 78 from its axis remains constant over a quarter-circumference 78a, then increases rapidly over substantially 45 along 78b, after which it continues to increase very slowly over a half-circumference 78c and finally decreases very rapidly over approximately 45 along 78a, to revert to its initial value. The direction of rotation of the cam is such that the follower 77 successively rides over the sectors 78a, 78b, 78c and 78d.

sectional view taken through The second sector 78b corresponds to a rapid approach of the rolling tool toward the container 2; the transit of the roller over the next sector 7 80 produces a slow travel of the tool in the same direction, during which phase the rolled edge is formed; the sector 78d corresponds to a rapid return motion of the assembly to its initial position following rapid opening of the jaws 28; the tool then remains in this position while the follower 77 rides over the cam sector 73a, during which time a fresh container can be moved into position for processing.

Except for these differences, the apparatus hereinbefore described operates exactly in the same manner as the apparatus which is described in the above-cited U.S. patent application Ser. No. 428,324.

What I claim is:

1. In an apparatus for forming rolled edges on a container of revolution made of sheet material, mounted on a fixed support comprising, in combination, a central part which is coaxial with the container mounted in its fixed support and which has formed thereon rearwardly of its periphery a circular hollow half-torus shaped throat at a distance from the container axis equal to the distanc from said axis of the container edge to be rolled down, a movable hollow supporting member coaxial with and spaced from the rear of said part, a plurality of jaws mounted on said supporting member, radially movable in said space in contact with said central part and said supporting member and projecting radially forwardly from the periphery of said central part, said jaws having formed thereon facing said part on their forwardly projecting portions a circular hollow quarter-torus shaped groove which, when said jaws are in their retracted positions, jointly form with said throat a rolling die the section of which is a hollow three-quarter-torus opening out in the direction of the container, means for applying said jaws against said flange under slight pressure, means for applying said central part against said jaws under slight pressure, means for axially displacing said supporting member toward the container whereby to roll back the edge thereof externally in said die and move said supporting member away from the container after formation of the rolled'edge, means for radially displacing said jaws between said supporting member and said central part on completion of the rolled edge whereby to open said die, means for reclosing said jaws on recession of said supporting member from the container with its rolled edge, and means for controlling said displacing means, the improvement comprising, in combination, means for rotatably mounting said rolling die about the axis of the container and means for rotating said rolling die.

2. An apparatus as claimed in claim 1, wherein said rolling die has radial splines with rounded corners formed thereon.

3. An apparatus as claimed in claim 2, wherein said central part and said jaws are made of treated steel.

4. An apparatus as claimed in claim 1, comprising a hollow tool body formed with a flanged end and a longitudinal groove, slides mounted on said flange and having openings therein, said central part and said jaws being mounted on said slides, pegs rigid with said flange, extending through said openings and penetrating into said central part, a hollow tool-carrier surrounding said tool body, a key rigid with the interior of said tool-carrier and penetrating into said groove, a fixed bearing in which said hollow tool-carrier is mounted, a pulley rigid with said toolcarrier and means for rotating said pulley.

5. An apparatus as claimed in claim 4, wherein said slide has a first circular groove formed thereon and said flange has a second circular groove formed thereon facing said first groove, a spring wire being accommodated in said grooves.

6. An apparatus according to claim 1, wherein said means for controlling said displacing means comprise a shaft slidably mounted in said hollow supporting member and of which the end remote from said container is threaded, an annular connecting member, a bearing mounted in said annular member and engaging over the threaded end of said shaft, two nuts on said threaded end on either side of said bearing, a link pivotally connected to said annular member, a fixedly fulcrumed lever pivotally connected to said link, a cam-follower on said lever, a cam with which said follower is in pressure contact, and means for rotating said cam about its axis.

7. An apparatus as claimed in claim 6, wherein the distance between the contour and the axis of said cam is constant over substantially rapidly increases over substantially 45, slowly decreases over substantially and rapidly decreases over substantially 45.

References Cited by the Examiner UNITED STATES PATENTS 2,473,836 6/1949 Wixon et al. 93-36.5 2,778,287 1/1957 Moore 93--36.5 2,819,658 l/1958 Scott et al. 93-365 WILLIAM W. DYER, 111., Primary Examiner.

JAMES M. MEISTER, Examiner.

Claims

1. IN AN APPARATUS FOR FORMING ROLLED EDGES ON A CONTAINER OF REVOLUTION MADE OF SHEET MATERIAL, MOUNTED ON A FIXED SUPPORT COMPRISING, IN COMBINATION, A CENTRAL PART WHICH IS COAXIAL WITH THE CONTAINER MOUNTED IN ITS FIXED SUPPORT AND WHICH HAS FORMED THEREON REARWARDLY OF ITS PERIPHERY A CIRCULAR HOLLOW HALF-TORUS SHAPED THROAT AT A DISTANCE FROM THE CONTAINER AXIS EQUAL TO THE DISTANCE FROM SAID AXIS OF THE CONTAINER EDGE TO BE ROLLED DOWN, A MOVABLE HOLLOW SUPPORTING MEMBER COAXIAL WITH AND SPACED FROM THE REAR OF SAID PART, A PLURALITY OF JAWS MOUNTED ON SAID SUPPORTING MEMBER, RADIALLY MOVABLE IN SAID SPACE IN CONTACT WITH SAID CENTRAL PART AND SAID SUPPORTING MEMBER AND PROJECTING RADIALLY FORWARDLY FROM THE PERIPHERY OF SAID CENTRAL PART, SAID JAWS HAVING FORMED THEREON FACING SAID PART ON THEIR FORWARDLY PROJECTING PORTIONS A CIRCULAR HOLLOW QUARTER-TORUS SHAPED GROOVE WHICH, WHEN SAID JAWS ARE IN THEIR RETRACTED POSITIONS, JOINTLY FORM WITH SAID THROAT A ROLLING DIE THE SECTION OF WHICH IS A HOLLOW THREE-QUARTER-TORUS OPENING OUT IN THE DIRECTION OF THE CONTAINER, MEANS FOR APPLYING SAID JAWS AGAINST SAID FLANGE UNDER SLIGHT PRESSURE, MEANS FOR APPLYING SAID CENTRAL PART AGAINST SAID JAWS UNDER SLIGHT PRESSURE, MEANS FOR AXIALLY DISPLACING SAID SUPPORTING MEMBER TOWARD THE CONTAINER WHEREBY TO ROLL BACK THE EDGE THEREOF EXTERNALLY IN SAID DIE AND MOVE SAID SUPPORTING MEMBER AWAY FROM THE CONTAINER AFTER FORMATION OF THE ROLLED EDGE, MEANS FOR RADIALLY DISPLACING SAID JAWS BETWEEN SAID SUPPORTING MEMBER AND SAID CENTRAL PART ON COMPLETION OF THE ROLLED EDGE WHEREBY TO OPEN SAID DIE, MEANS FOR RECLOSING SAID JAWS ON RECESSION OF SAID SUPPORTING MEMBER FROM THE CONTAINER WITH ITS ROLLED EDGE, AND MEANS FOR CONTROLLING SAID DISPLACING MEANS, THE IMPROVEMENT COMPRISING, IN COMBINATION, MEANS FOR ROTATABLY MOUNTING SAID ROLLING DIE ABOUT THE AXIS OF THE CONTAINER AND MEANS FOR ROTATING SAID ROLLING DIE.