JP2001121231A - Method and device for correcting end part of container - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method and a device for correcting the end part of a container capable of giving high strength to the container and suppressing bulging of the container. SOLUTION: A container is provided with a side wall, an end part integrated with the side wall and the end part has a center dome shape and a counter sink having an annular inner wall extending substantially in the longitudinal direction and an annular outer wall. In the correction method of the bottom part of the above container, a correction roller is used, the correction roller is engaged with the inner wall of the container and is rotated along the inner wall around the path to correct the inner wall. The correction roller has a peripheral shape to regulate the wall which has a roughly arc section and is inclined roughly vertically upward and toward outside.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

FIELD OF THE INVENTION The present invention relates generally to the construction of two-part containers and, more particularly, to a method and apparatus for processing such containers to increase their strength and improve their appearance.

[0002]

BACKGROUND OF THE INVENTION Two-part cans are the most common type of metal container used in the beer and beverage industry and for aerosol and food packaging. A two-part container consists of a single body that includes a side wall that opens at one end and has an integral end wall at the other end. The integral end wall is typically formed in a dome shape to increase the strength of the entire container. An annular portion is usually formed in a special shape between the central dome-shaped panel of the bottom wall and the side wall defining a reduced diameter support for the container, and its open end Provide a nesting feature for nesting with the edge of an adjacent container, which is spliced.

[0003] An exemplary bottom profile for drawn, surfaced containers that has achieved remarkable market success is disclosed in US Patent No. 4,685,58.
No. 2. The container disclosed there is also
The panel at the second end or the end with the smaller diameter has a reduced neck so that it can be used to surround an open, drawn, surfaced container open at one end. Includes upper end portion to hold.

[0004] In most cases, the containers used for beer and carbonated drinks are made from flat aluminum discs.
Formed to an outer diameter of 11/16 inches (referred to as "211-container"), the upper open end of the upper end so that the smaller diameter end can be used in the finished package. The diameter is 209-neck (2-9 / 16 inch) or 207-1 / 2-neck, some other smaller diameter such as 206-neck, and 204-neck or smaller neck Is reduced to form

[0005] An important competing goal in the packaging industry is:
The goal is to reduce the total can weight as much as possible while maintaining its strength and performance in accordance with the needs of the industry. For pressurized contents, such as soft drinks or beer, the wall at the integral bottom end of the container usually has a standard substrate of the same metal thickness as the original disc, and the side walls 1 / th of the thickness of the first metal disk through the drawing and surface smoothing process
It is reduced at a thickness close to 3. Thus, in order to minimize the overall weight, the can top or end panels that make up the second part of the two-part can have a structural integrity of the container, its functionality, and an aesthetically pleasing appearance. The diameter is formed as small as possible while maintaining the diameter.

In the manufacture of this type of container, a sheet of storage material of a predetermined thickness is fed to a cup making press, where a disk is cut from the storage material and significantly larger than the final diameter of the finished container. Transferred into a cup with a large diameter. The preformed cup is then passed to a container former, commonly referred to as a "body maker," where the cup is placed at the end of a plurality of spaced surface leveling dies and punch passages. Aligned with a punch carried on a reciprocating ram that operates with a dome forming mechanism located at During the forming process, it first works with the redraw assembly, where the shallow cup has an inside diameter approximately equal to the inside diameter of the finished container and a height greater than the height of the first cup,
Redrawn to a smaller diameter.

Each cup then passes through a series of surface leveling dies having progressively smaller diameters so that the thickness of the container sidewall is progressively reduced while the height of the container is reduced. It increases. At the end of the stroke for punches or sticks, the end of the container forms a unitary end wall with a dome-shaped overhanging panel in the middle and a specially shaped peripheral annular support part Therefore, it is forcibly formed in a predetermined shape. The drawn and surfaced container is then cut into a selected height, coated and labeled, with a sloping neck with a small diameter at the open end Is formed.

[0008] The assignee of the present invention is intended to produce containers which are competitive in price and which can meet the stringent industry demands for pressurized contents, especially beer and carbonated beverages. Has developed a cervical shaping operation using a mold to progressively reduce the open end of the container to a smooth, molded cervical shape. This is done through multiple passes until the desired reduction for the end, such as the 206 or 204 end, is achieved.
This process is disclosed in U.S. Pat. No. 4,774,839, which is incorporated herein by reference. Bottom profiles as disclosed in U.S. Pat. No. 4,685,582 and of the type having a smooth, molded neck shape illustrated in the patents listed above. The container has enhanced strength properties, enhancing the overall aesthetic appearance.

In order to further improve the overall appearance of the drawn, surfaced container consisting of two parts, US Pat. Nos. 283,011 and 290,
It has also been proposed to modify the side walls of the container to create a fluted appearance as disclosed in US Pat. According to the present invention, only one drawn, formed from a minimum amount of storage material and capable of meeting all the stringent demands for a container particularly suitable for use in the beer and beverage industry. A surfaced container was developed.

In particular, the container of the present invention can be formed from a storage material, preferably a flat disc of aluminum having a thickness of less than 0.0120 inches, with a minimum push of 250 pounds and 90 psi, respectively. Crushing and twisting requirements can be met. A container formed of a flat aluminum disc made of aluminum, preferably has a bottom wall having a thickness substantially equal to the thickness of the storage material and a side wall thickness of the order of 1/3 of the thickness of the storage material. The bottom wall is connected to the sidewall through a countersink having outer and inner, generally flat, substantially vertical walls,
It has a dome-shaped panel towards the center.

The side wall of the container is a plurality of circumferentially spaced, axially extending, inwardly deformed panel portions substantially co-axial with the remainder of the side wall. Formed between the rising areas or arc-shaped portions of
It smoothly merges with the side walls adjacent the opposing ends of those panel portions. These panel parts are at the junction of the bottom countersink and the open end above the container,
It is located inside the boundary of the side wall between the inwardly inclined neck joints.

[0012]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a method and a device for modifying the ends of a container which are high in strength and reduce the expansion of the container.

[0013]

SUMMARY OF THE INVENTION A method according to the present invention includes a side wall and an end integral with the side wall, wherein the end has a central dome-shaped portion and an annular substantially vertical length. A method of modifying the bottom of a container having an inner wall extending and a countersink having an annular outer wall, the method comprising: providing the container, providing a correction roller, engaging the correction roller with the inner wall, and correcting the inner wall. Rotating the correction roller along the inner wall about an arcuate path to accomplish this.

The device according to the invention has a side wall and an end integral with the side wall, the end comprising a central dome-shaped portion,
An apparatus for modifying a bottom of a container having an annular substantially longitudinally extending inner wall and a countersink having an annular outer wall, wherein the radius engages the inner wall from a radially inner position that does not contact the inner wall. A correction roller movable to an external position in the direction.

[0015]

BRIEF DESCRIPTION OF THE DRAWINGS Since the present invention can be embodied in many different forms, it is shown in the drawings, in which the present disclosure is to be considered as illustrative of the present invention. Preferred embodiments of the present invention are described in detail with the understanding that the broad aspects are not intended to be limited to the illustrated embodiments.

FIG. 1 of the drawings discloses a container processing apparatus, generally designated by the reference numeral 20, consisting of a base (FIG. 2) having an upright central post or column 24 supporting a rotatable turret 26. The turret 26 is rotated around a central support means or column 24 through drive means 28 mounted on the base 22. The turret 26 has a plurality of substantially identical processing stations 30 mounted therearound. There are twelve stations as shown in FIGS. 1 and 2, but the number can easily be increased or decreased in connection with the manufacturing facility.

The drawn and smoothed container, consisting of the two conventional parts before neck and flange formation, is fed to the processing equipment via a feed mechanism 32 and a discharge mechanism 3 is provided.
4 from the processing equipment. Supply mechanism 3
2 includes a conventional star wheel 36, which has a plurality of peripheral pockets 38 for receiving containers from a continuously moving conveyor 40 for feeding to each of the processing stations 30. I have. Preferably, the feeder 32 includes a guide rail 42, which guides the container along a stationary plate 44 so as to be picked up at each of the stations 30, as described below.

Similarly, the discharge mechanism 34 includes a second star wheel 46 and a continuously moving conveyor 40.
Because of the final supply to
It has pockets 48 for receiving machined or fluted containers from each of the four, where those containers are transported for further processing. The ejection mechanism 34 again has an arcuate guide plate 49, as shown in FIG. The processed container is a star wheel 4
6, it is pulled out of the processing station 30 and guided along the support plate 44 to the conveyor 40.

As shown in FIGS. 1 and 2, each station 30 incorporates a support mandrel 50, a platform 52 mounted on a piston rod 53, and a push mandrel 54 (FIG. 2). Platform 52
Is supported on a piston rod 53 which is vertically reciprocated within an opening in the turret 26 through a cam mechanism of a known type (not shown). The cam mechanism for moving platform 52 between the low and high positions could be of the type shown in U.S. Pat. No. 4,519,232, which is incorporated herein by reference. .

In this way, the container C is supplied from the supply mechanism 32 to the platform 52 while the platform is in the low position shown to the left of the extended platform in FIG. Is lifted by the cam drive mechanism to introduce or load onto the support mandrel 50. Loading mechanism 52, 5
3 may incorporate a vacuum source (not shown) to hold the container on the platform 52 before being received in the support mandrel 50.

The supporting mandrel 50 and the pressing mandrel 54 are continuously driven in a synchronized manner by a common drive mechanism (FIG. 1), which is supported on the upper end of the stationary column 24, A central fixed drive gear 60 meshing with the plurality of driven gears 62 is included. The driven gears 62 are in driving engagement with gears 64 mounted on a support shaft 66 having a support mandrel 50 mounted on the lower end. In addition, each driven gear 64 meshes with a combined gear 70 mounted on a support shaft 72 that supports the pressing mandrel 54. In this way, with proper choice of gear diameter and ratio, shafts 66 and 72 are driven at a common speed, and thus mandrels 50 and 54 are driven at a common speed for the purposes described below. I do.

According to one aspect of the invention, each push mandrel is such that the mandrels 50, 54 are rotated such that the turret 26 rotates and deforms the container C between the respective mandrels, as described below. It is designed to engage or not press with the support mandrel 50 while being actively driven. According to one aspect of the present invention, a pair of adjacent pressing mandrels 54 are supported on a common support mechanism and are simultaneously moved by a simplified cam drive mechanism, the drive mechanism comprising: With particular reference to FIGS. 4 and 5.

As shown therein, the pressing mandrel 5
The support mechanism for the adjacent pair of processing stations 3
It includes a support shaft 80 mounted on the turret 26 between zeros. The support shaft 80 has a pair of arms 82 extending therefrom which, as will be described, are provided in a desired angular orientation by a suitable set of screws (not shown). To the support shaft 80.

Each of the arms 82 has a hollow support stove 84 fixed to its outer free end, which in turn supports a shaft 72 having a push mandrel 54 supported at its lower end. . Preferably the shaft 72 is split and the upper part 72a having a gear 70 attached thereto
And a lower portion 72b supporting the mandrel 54. A suitable bearing 86 is interposed between the shaft 72 and the hollow support member 84 with a spacer sleeve 87 interposed therebetween, as shown in FIG.

Preferably, each push mandrel 54 includes a central rigid core 90, which is a deformable or compressible outer member 92, preferably formed of a polyurethane material or a suitable equivalent material. I support.
In one embodiment of the invention, the push mandrel 54 absorbs a controlled differential speed or speed between the push mandrel and the support mandrel, rather than the common or uniform speed previously described. The lower support part 7 via a friction drive structure
2b. As shown in FIG. 5, the lower shaft portion 72b has a spacer collar 94 which is interposed between the bearing 86 and the hard core 90, and the pressing mandrel is located below the lower support shaft 72b. Are pressed against a collar 94 via a threaded fastener 96 which is received in a threaded opening 97 formed at the end of the collar 94. A spring washer 99 is interposed between the upper edge of the core 90 and the lower edge of the collar 94.

Thus, the hollow core 90 and the core 72
The amount of frictional tension created during b can be precisely controlled by the appropriate torque applied to the fastener 96 that compresses its spring washer 99 to create the desired frictional tension. This provides a controlled differential speed between the positively geared support mandrel 52 and the push mandrel 54. Additional frictional force can be created by appropriate sizing of the shaft 72b relative to the core 90.

According to a principal aspect of the present invention, the supporting mandrel is pressed by the pressure of the pressing mandrel so that the supporting mandrel creates a plurality of arcuate portions which are deformed inwardly from the initial side wall of the container. It is formed and designed to be deformed in a support mandrel. Thus, FIG.
As shown in FIG. 13 and FIG.
0 includes a hollow circular core 100 having a circular peripheral surface 102 having a diameter substantially equal to the inner diameter of the container side wall. After the mandrel is finished to a cylindrical shape that matches the inside diameter of the container, a plurality of circumferentially spaced, axially extending pockets 104 are formed in the support mandrel 50, such as by machining. Formed on the surface.

In particular, each pocket 104 is formed by machining a portion from the surface of the support axle 50 between adjacent pairs of raised areas 106. The raised area 106 has an outer surface 102a that matches the radius of the surface 102 of the core 100 and has flat sidewalls 108 interconnected by a flat bottom wall 109 that defines a chord surface between the raised areas 106. ing. Core 100
A flat sidewall 108 extending radially from the axis intersects the surface 102a to form a sharp edge 108a. FIG.
As clearly shown in FIG. 4, the shape of the cross-section of each raised area is approximately square, approximately 0.03
It has a depth of 0 inches and a width of approximately 0.030 inches. In this exemplary embodiment, the support axle is
As shown more clearly in FIG. 11, it is designed to make cans or containers having what is referred to as 30 equally spaced flutes formed in the side walls of the container.

For such an embodiment, the center-to-center spacing between adjacent elevation regions 106 is about 12 °, and thus the depth of pocket 104 is about 0.030 inches. . As shown in FIG. 13, the opposing ends of the pockets 104, especially the bottom wall 109, are spread out in a glaze at 109a and fuse with the outer surface 102 of the support mandrel 50 through a smooth transition. I have.
The function and operation of the pocket 104 will be described in detail in connection with the operation of the device described below.

As described more fully above, each push mandrel 54 operates with the support mandrel 50 to interpose the container sidewall between arcuate portions having a diameter equal to the diameter of the container sidewall. It is transformed into a plurality of "string parts". For this purpose, the pressing mandrel 54 is connected to the supporting mandrel 5 during rotation of the turret 26 surrounding the supporting column 24.
It is supported for movement in and out of the can body above the zero.

For this purpose (FIG. 1), the upper end of the column 24 has a stationary cam 110 attached to it, having a peripheral camming surface 112. The surrounding camming surface 112 works with a cam follower 114 mounted on an arm 116 fixed to the upper end of the support shaft 80. In this manner, rotation of the turret 26 causes the cam follower to follow the cam surface 112,
The support shaft 80 is swung around the support shaft. This causes the support arm 82, together with the push mandrel 54, to swing in and out of pressure engagement with the can body C on the support mandrel 50 associated therewith during each rotation cycle of the turret.

The operation of this device is summarized here. The top opened, drawn and surface smoothed container is fed from the conveyor 40 by the feeding mechanism 32 to the station 30.
Supplied to The containers are received on platform 52 and loaded onto support mandrel 50 at each station while turret 26 and support mandrel 50 are rotating.

The pressing mandrel 54, actively driven by the support mandrel, then cams by rocking the shaft 80 through the cam 112 and arm 116 to lock the can body and deform the container side wall. It is brought into pressure contact using. During this deformation, fold lines are formed in the container sidewall by the raised areas or sharp edges 108a of the ribs 106, and chord portions are formed between the fold lines.

The amount of deformation of the chord portion is controlled by changing the engagement pressure between the pressing mandrel and the support bar. The engagement pressure is then controlled by adjusting the angular orientation of arm 82 on shaft 80. Since the effective diameter of the compressible outer member 92 of the push mandrel 54 varies with the pressure between the mandrels, the friction drive between the shaft 72 and the mandrel 54, particularly the spring washer 99 and the core 90, is combined with the ambient speed of the support mandrel. Pressing on the mandrel will adjust the peripheral speed. Therefore, their speeds are synchronized.

The deformed side wall 1 of the container is thus obtained.
29 takes the shape shown in FIG. 11, where a plurality of deformed portions 130 are defined between adjacent raised areas or arcuate portions 132. Arc-shaped part 1
32 has a peripheral arc shape that matches the arc shape of the container side wall. Opposite edges of the deformed portion 130 are fold lines 13 created by the sharp edges of the mandrel 50.
2a.

[0036] The container also contains the '839 discussed earlier.
A narrow neck 134 and outwardly directed flange 136 formed thereon by a neck forming process using a mold, disclosed in the patent, and the ANC-type disclosed in the '582 patent. It has a bottom profile called 1A bottom profile. Both patents are included here for reference.

Using the apparatus described above, the container shown in FIG. 11 fluted, finished, drawn and textured, is now used on a commercial scale, Draw-processed, surfaced containers have demonstrated high physical properties never before experienced. In fact, containers incorporating fluted sidewalls exhibit significantly greater crush strength than the same non-fluted containers without fluted sidewalls. Moreover, those containers have the same cutting edge diameter as conventional discs,
Formed from storage material or disks of small thickness.

In comparison of the crushing strength, 0.011
The same fluted container formed on a thin side wall having a thickness of approximately 0.0045 inches from an aluminum storage material or disc having a thickness of 9 inches and a non-fluted side wall (Circle), which showed the following crushing properties: Table 1 Crushing strength of empty cans (lbs) Side wall strength Round standard neck Vertical fluted round Standard neck fluted Min 298 335 0.0044 0.0044 Max 337 337 0. 0045 0.0046 Average 318 336 0.0044 0.0045 The above data show that the fluted container has a very uniform crush strength of an average of 336 pounds, much higher than the required minimum of 250 pounds. This is clearly shown. The same, fluted, round-sided container collapses at the bottom of the body, while the fluted container swells and collapses just above the junction between the side wall and the bottom profile. It was also decided not to. Although not thoroughly examined, it appears that the boshed end of the chord portion 130 adjacent the junction with the integral bottom wall increases the crushing strength for the container.

These containers were formed with the following parameters: Fluted can volume 206/211 x413 "A" cervix with neck formed using ANC-1A Type of can Description Can height Dome depth Overhead overflow capacity Round standard neck 4 .818. 381. 499 13.17 fluted 4.814. 380. 475 13.15 Standard Neck The same container was subjected to a single can drop test after being filled with a commercially available soft drink beverage product. The single can bottom drop test is performed to evaluate the resistance of the bottom wall to turning over the dome when the can is dropped against the wall of the integral bottom end. The test apparatus consisted of a four foot tube securely attached to a hard steel base, and the cans were dropped from various heights until the dome turned over.

Twenty-four fluted and non-fluted (checking) cans were subjected to a drop test, which checked for "rocker" defects with a drop of about 29 inches. Indicated. On the other hand, the fluted cans did not experience any "rocker" defects at a maximum drop of 4 feet. The “rocker” defect is when the profiled bottom wall of the container is placed on a flat surface
Occurs when turning over to a point where it can no longer be stable. These containers are filled with Classic Coke® soft drink and at a temperature of 76 ° F. for 15 minutes.
Dropped on a 0 lb "B" flute test plate.

The fluted can and the check can are D
Filled with IEt-Caffeine Free-Coke and subjected to a drop test at 76 ° F on a 0.024 inch Mead chipboard jacket. The check container suffered a "rocker" defect with a drop of about 8 inches.
On the other hand, the fluted container suffered a "rocker" defect at about a 23 inch drop.

Thus, it was concluded that the fluted container had a much improved crush resistance with the least variation from container to container. Also, fluted containers have much greater resistance to turning over the dome. That is, they can better absorb hydrodynamic shock. Although the parameters have not yet been thoroughly investigated, fluted containers also reduce the bending resistance of the filled container when the product is exposed to high temperatures during storage in hot weather. Improve. The fluted container also eliminates "gull wings". It can lead to crushed containers during filling and edge splicing operations. The "gull wing" defect is a slight imperfection in the side wall of the container, which creates a corrugation in the side wall during the container forming operation.

Another factor that seems very important is the length of the flute in the side wall and its relationship to the junction between the side wall and the angled neck and to the integral bottom wall. The flutes, i.e. the opposing ends of the chord panel sections, must be as close as possible to their joints and must not intersect them. It has been determined that a spacing of about 0.050 inches from the ends of the flutes, measured from their junction, creates an ideal container. However, their dimensions can be easily varied without significantly departing from the spirit of the invention.

The above tests also show that the containers exhibit significantly greater resistance to internal pressure without causing any damage to the container. The flutes built into the side walls have the ability to absorb a significant amount of hydrodynamic shock when the containers are dropped during a standard drop test. The formation of internal pressure tends to return the chords between the raised areas of the side walls to the general arcuate shape of the side walls of the container, without causing any damage to the side walls of the container. Provides greater resistance to increased pressure. Because of the flutes, its internal pressure is without any significant effect on the walls of the dome-shaped end of the container, i.e. without a significant degree of container growth or dome inversion
It was also determined that it could be larger.

Actual tests have shown that the metal thickness of the storage material of the disc to form the drawn, surfaced container of aluminum does not sacrifice any strength properties of the container. Showed that it can be further reduced. For example, tests have shown that storage material can easily be reduced to a thickness of 0.0118 inches, perhaps well below that level, without sacrificing strength properties for the container. .

Although the parameters have not yet been thoroughly investigated, the greater the length of the flute between the shape of the dome end and the neck of small diameter, the better the performance characteristics expected. It is believed that you can. In this way, the pocket 13 formed in the side wall of the container
The arcuate ends of the 0 have narrowed neck 134 and bottom 137
It is expected to merge with the sidewall just inside the fold line defining the boundary of the sidewall to.

Additional tests were performed to determine the potential for reducing the thickness of the sidewalls in the container while maintaining the minimum performance characteristics for the fluted container.
These tests do not account for any rolling or damage to the dome or any dents in the neck area of the container, but actually measure the amount of abuse that the container sidewall can absorb before damage occurs to the sidewall. Made to decide.

A drawn and leveled aluminum container was formed from a stock disk of 0.0120 aluminum on a commercial D81 machine. These containers were regular 12 ounce containers having 211 side wall diameters and 413 heights with 206 necks narrowed to 206 ends. The container sidewall was thinned to an average thickness of 0.0039 inches. Check containers were tested and compared to fluted containers consistent with the teachings of the present invention.

The containers produced the following results in crush strength in pounds. Checking container Vertically crushed container Vertical crushing Side crushing Vertical crushing Side crushing Minimum 214 76 272 74 Maximum 293 80 313 76 Average 249 78 299 76 These fluted containers are also It exhibited an average elongation (container growth) at a peak load of about 0.04 inches. On the other hand, the check container showed an average elongation of 0.03 inches.

The dome depth for these containers is 0.3
When below the acceptable minimum of 80 inches, i.e., when the depth was about 0.363 inches, it was tested to determine vessel growth for internal pressure and minimal acceptable bending pressure (psig). The following test results were recorded. Dome Growth and Bending Body Variables Sample Dome Depth Dome Depth after PSIG 75 80 82 85 90 Bend 1.363 .006 .011 .030 .048 .065 94 Done 2.363………. 049 .069 95 1 .363 .004 .009 .028 .047 .063 95 Round 2.363…… .048 .066 95 AIM .380…… .045 .064 90 +/-. 0004 Highest Highest Lowest ( ANC-1A) These vessels exhibited unacceptable growth due to worn tools and / or thermal stress. However, these test results show that fluting the sidewalls allows the sidewall thickness to be reduced without sacrificing performance characteristics such as crushing strength, container growth, or resistance to bending. To indicate that

According to another aspect of the present invention, a container formed according to the above teachings and disclosed in FIG.
As disclosed in the previously mentioned '582 patent,
By reshaping the bottom end wall of the container from its original shape, it has improved performance characteristics that are even better. In this way, as shown in FIGS. 9 and 10, after the fluted container has been neck-formed, flanged, spray-coated internally and printed on the outside The bottom profile, especially the area of the countersink or protruding edge of the bottom wall, can be reshaped by reforming the inner wall of the countersink to further improve bending resistance and reduce can growth .
This special process will also allow the thickness of the storage metal to be reduced without any change in the diameter of the cutting edge of the initial disc.

Thus, as shown in FIG. 9, the finished, drawn and surfaced container of FIG. 11 has an internal opening 152 corresponding to the outer diameter of the container C. It is supported in a suitable jig 150 that it has. The jig has a lower profile portion 154 that fits the countersink wall portion of the bottom wall of the container as originally formed in accordance with the method disclosed in the '582 patent.

A plug 156 is inserted into the upper end of the opening and is held firmly on top of the container. The profile 154 around the bottom of the jig 150 has extensive contact with the bottom 137 of the container. The correction roller 160 is provided at the dome-shaped end 16 of the container.
2 and supported on a shaft 164 designed to be rotated along an arcuate path around a central shaft for the container C. Correction roller 160
Is a substantially vertical, upward and outward facing having a generally arcuate upper portion 168 such that the inner wall 170 of the countersink is modified to a more vertical profile while the dome 162 is stretched to a lesser extent. And has a peripheral shape 166 defining a sloped wall. Outer wall 172 is maintained in its original shape. As an alternative, the outer wall could also be modified along with the inner wall.

This corrective action significantly improves the bending resistance,
It has been found that the growth of the can, i.e. when pressure is applied from the inside of the container, reduces the amount by which the bottom end wall is stretched. Thus, in summary, containers made in accordance with the method and apparatus of the present invention have been found to have significantly higher column strength, i.e., resistance to crushing due to vertical loads applied to the side walls of the container, and from the inside. It has significantly less vessel growth when pressurized and has improved bending resistance. It has been found that containers constructed in accordance with the present invention can be made from storage flat disc material having a significantly smaller thickness.

Although particular embodiments have been shown and described, many modifications may be made without departing from the spirit of the invention, and the scope of protection is limited only by the appended claims. is there.

[Brief description of the drawings]

FIG. 1 shows a processing device configured in accordance with the present invention;
FIG. 4 is a top view with some parts broken and removed.

FIG. 2 is a side elevation view of the device shown in FIG.

FIG. 3 is a side view of the device taken along line 3-3 in FIG. 2;

4 is a partial plan view of a pair of pressing mandrels forming part of the apparatus of FIG. 3;

5 is a sectional view taken along line 5-5 in FIG.

FIG. 6 shows the relationship of a pressing mandrel in relation to a pair of forming or supporting mandrels at one processing station.
3 is a schematic top view of various stations of the apparatus shown in FIG.

FIG. 7 is a partial side view showing details of one of the processing stations as viewed along line 7-7 of FIG. 6;

8 is a cross-sectional view taken along line 8-8 of FIG. 7, including a portion of the can wall showing the joint movement of the pressing mandrel and the support mandrel.

FIG. 9 is a partial cross-sectional view showing an apparatus used for reforming a container bottom wall.

FIG. 10 is an enlarged partial sectional view similar to FIG. 9;

FIG. 11 is a perspective view of the finished container after a neck forming and flange forming operation.

FIG. 12 is a perspective view of a forming mandrel.

13 is a sectional view taken along line 13-13 of FIG.

FIG. 14 is a sectional view taken along line 14-14 of FIG. 12;

[Explanation of symbols]

 129: Container side wall 137 ... Container end 150 ... Jig 160 ... Correction roller 162 ... Dome 166 ... Surrounding shape 170 ... Inner wall 172 ... Outer wall

 ──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Platron, Sylvan, USA 60615, Illinois, Chicago, South Ellis, 4822

Claims (12)

[Claims] 1. A countersink having a side wall and an end integral with the side wall, the end having a central dome-shaped portion, an annular substantially longitudinally extending inner wall and an annular outer wall. Providing the container, providing a correction roller, engaging the correction roller with the inner wall, and surrounding the arcuate path to correct the inner wall. A method comprising rotating a correction roller along an inner wall. 2. The method of claim 1 wherein said inner wall is modified to a more vertical position. 3. The method of claim 1 wherein said modifying roller has a peripheral shape defining a generally vertical, upwardly and outwardly sloping wall having a generally arcuate portion. 4. The method of claim 1 including providing radial inward support for said container. 5. The method of claim 4, wherein providing the radial inward support comprises supporting the container in a jig. 6. The method of claim 5, wherein said jig includes a bottom outer peripheral profile portion shaped substantially corresponding to said annular outer wall of said container. 7. The method of claim 1 wherein providing the container comprises providing a drawn and surfaced container body formed from a single metal plate. 8. A side wall having an end integral with the side wall,
A device for modifying the bottom of a container, the end having a central dome-shaped portion and a countersink having an annular substantially longitudinally extending inner wall and an annular outer wall, the radius not contacting said inner wall. A correction roller movable from a directional inner position to a radially outer position engaging said inner wall. 9. The apparatus of claim 8 having a radially inward support. 10. The apparatus of claim 9, wherein said radially inward support comprises a jig. 11. The apparatus of claim 10, wherein said jig includes a bottom outer peripheral profile portion shaped substantially corresponding to said annular outer wall of said container. 12. The apparatus of claim 9, wherein said modifying roller has a peripheral shape defining a generally vertical, upwardly and outwardly sloping wall having a generally arcuate portion.