GB2102367A - Aerodynamic transfer system for progressive manufacturing apparatus - Google Patents

Abstract

Apparatus for transferring cuplike articles between work stations 4-8 of a progressively operating tooling apparatus. The work stations are located at the juncture 20 of perpendicularly disposed channel segments where the article may be held by a vacuum during the tooling operation. Articles may be advanced from one work station to the next by an air jet directed along the intermediate channel sections. At the final work station, the article is moved axially of itself from the transfer channel. <IMAGE>

Description

SPECIFICATION Aerodynamic transfer system for progressive manufacturing apparatus SUMMARY OF THE INVENTION The present invention is directed generally to an article transfer system, and more particularly to a conveyor system for transferring an article between and holding the article at a multiplicity of successive work stations where an operation is performed on the article.

The present invention finds particular applicability in the manufacture of shell-like articles such as cylindrical two-piece cans and flashlight battery shells.

As is well known in the art, such cylindrical articles are generally blanked and drawn from a coil of metallic strip stock, and are subsequently redrawn one or more times in order to reduce the diameter while increasing the article height.

Fundamentally, the article is first blanked from a strip and drawn downwardly through a draw die, thus creating a cylindrical-shaped cup which is relatively large in diameter and short in height.

This cup is stripped from the tooling and is disposed with its bottom on a pass line. The cup is then moved to a second work station by a flow of air where it is redrawn and its diameter reduced.

Conventionally, at the second work station there are lateral stops of a size to prevent passage of the cup in its initial condition but to permit passage after it has been redrawn and its diameter reduced. Similar arrangements may be provided at other intermediate stations where operations are performed on the cup which reduce its diameter.

At a final station, the flange is trimmed and the completed can can be discharged from the device.

The stops at each of the stations are provided with vacuum openings so that the can is held firmly in position at the stations for the operation which occurs. After the cup has been redrawn at any of the intermediate stations, a lifter may be provided to lift it back up to a position where its bottom is on the pass line so that it may be transferred to a succeeding station by airflow or other suitable means. A typical system operating in this manner is described and illustrated in U.S. Patent No.

RE29,645 reissued May 30, 1978 to Elton G.

Kaminski.

In some instances it has been found that the particular operation performed at a work station does not serve to reduce the diameter of the cup.

For example, a particular operation may be performed where a hole is pierced in the bottom of the cup, or the side walls of the cup are wall ironed to maintain the same diameter but increase the article height. In these cases, the types of constrictive lateral stops described in the aforementioned reissue patent would not serve to hold the cup in position during the operation at a particular work station. Consequently, in these cases, mechanically activated intermediate stops must be provided which are timed with the action of the press ram.

The present invention is directed to the aerodynamic transfer of such articles where a change in article dimension and intermediate mechanical stops are not required. The invention finds particular applicability in apparatus for manufacturing cylindrical cup-like articles such as can bodies or battery shells. This type of apparatus usually employs a plurality of spaced work stations for performing a series of successive operations on the articles, with the stations being connected by a channel for transferring articles from one work station to the next. In the preferred embodiment described, progressive operations comprising blank and draw, redraw, bottom form, pierce and trim are provided.

In the present invention, the channel is formed by a plurality of linear but angularly disposed channel segments which form right or obtuse interior corners at their junctures. With the exception of the initial blank and draw station, a work station is located at each of the channel segment junctions. Interior corners form rounded surfaces for insuring surface-to-surface contact with the cup-like article in order to accurately position it at a particular work station during the operation. A vacuum port is also associated with each corner for snugly holding the article against the round surface during the manufacturing operation.

The articles are advanced from one station to the next by means of an air jet associated with the previous station which pushes the article into the successive rounded corner. The vacuum ports and air jets are accurately timed with the tool operation.

At the final or terminal station, a movable stop is provided which permits the can to be moved axially by gravity below the pass line and conveyed to a subsequent manufacturing station.

As will become apparent from the detailed description which follows, the present invention provides means for holding the cup accurately in position at each work station regardless of whether the size or diameter of the cup is changed. As a result, manufacturing operations such as piercing or wall ironing may be performed without the need for complex mechanical holding fixtures.

Further details of the invention will become apparent from the detailed description which follows.

BRIEF DESCRIPTION OF THE DRAWING Fig. 1 is a fragmentary diagrammatic perspective view of the aerodynamic transfer system of the present invention.

Fig. 2 is a fragmentary diagrammatic top plan view of a four-out progressive manufacturing tool utilizing the aerodynamic transfer system of the present invention.

Fig. 3 is a fragmentary enlarged top plan view of a single tooling lane utilizing the aerodynamic transfer system of the present invention.

Fig. 4 is a fragmentary cross sectional view taken along section line 4-4 of Fig. 3. DETAILED DESCRIPTION The present invention is described and illustrated in connection with progressive tooling apparatus, shown generally at 1 , for manufacturing a shell-like or cup-like article such as a can body or battery shell. In the specific embodiment described and illustrated diagrammatically in Fig. 2, the tooling 1 employs four tooling lanes 2. However, it will be understood that each tooling lane is identical in construction and operation. Consequently, only one of the lanes, illustrated generally at 3, will be described.

In the specific embodiment described, each tooling lane 2 includes five work stations comprising a blank and draw station 4, a redraw station 5, a bottom forming station 6, a piercing station 7 and a trimming station 8. However, it will be understood that any number of successive work stations may be provided for a particular application. Furthermore, the details of the blanking dies and the redrawing dies, as well as the respective plungers are not shown in detail inasmuch as these features are conventional and well known and understood by those skilled in the art.

In the first or blank and draw station 4, a circular blank 9 is punched from a sheet of metallic material. As is well known in the art, sheet material 10 may be fed from a coil of the material (not shown), and advanced in the direction of arrow 11 following each blanking operation.

Following the blanking operation, the circular blank 9, illustrated in dashed lines in Fig. 1, is drawn by means of die member 12 in blanking and drawing station 4 to form a relatively wide and shallow cylindrical cup 1 3a. After cup 1 3a has been drawn, it is stripped downwardly by stripping means (not shown) and winds up in the position illustrated in Fig. 4 where the bottom of the cup rests on a horizontally disposed pass line 14.

It will be observed that pass line 14 forms the lower surface of a trough-like channel, shown generally at 1 5, which serves to guide the cups through successive work stations of the tooling apparatus. Channel 1 5 includes a first straight channel segment 1 6 which extends from blank and draw station 4 to redraw station 5. Cup 1 3a is advanced through first channel segment 1 6 by means of an air stream moving parallel to the channel segment produced by an air jet 17 positioned upstream of blank and draw station 4.

Pressurized air, synchronized with the operation of the blank and draw tooling, may be supplied to air jet 17 in the direction of arrow 18 by a source (not shown).

At redraw station 5, channel 15 turns to the right by means of a straight second channel segment 19 oriented perpendicularly to first channel segment 16. As best shown in Fig. 1 and Fig. 3, the junction of channel segments 16 and 19 forms a generally rounded interior corner 20 having a diameter substantially the same as the outer diameter of drawn cup 1 3a. It will be observed that the radius of curvature of rounded corner 20 is sufficient to insure surface-to-surface contact with at least about one quarter of the outer surface of drawn cup 13a.

Cup 13a is pushed into corner 20 by the force of the air stream emitted from air jet 17, which is properly timed in relation to the blanking, drawing and redrawing operations by means not shown.

Cup 13a may be snugly held within corner 20 to accurately position the cup during the redrawing operation by means of one or more vacuum ports, one of which is shown at 21, which is positioned at the center of curvature of rounded corner 20 and operates to draw the cup against the rounded corner surface. The vacuum caused by the vacuum port will be synchronized with the tooling operation to hold and release the drawn cup 13a for the proper time period.

During the redraw operation, cup 13a is drawn to an elongated and reduced diameter condition indicated at 13b. Following the redraw operation, the bottom of the cup 13b is positioned below pass line 14. At this point, a lift-out pad 22 operated by a cam, spring or air pressure means (not shown) operates to lift the redrawn cup 13b so that the bottom of the cup is again co-planar with pass line 14. This construction is conventional and well understood in the art.

At this point, pressurized air is supplied to an air jet 23 positioned coaxially with second channel segment 1 9 at corner 20 to push or advance redrawn cup 13b through the second channel segment toward bottom forming station 6.

As can best be seen in Fig. 1 and Fig. 3, the bottom forming station 6 is positioned at the junction of second channel segment 19 and a straight third channel segment 23. Third channel segment 26 is oriented perpendicularly to second channel segment 19 and extends to the right therefrom. It will be observed that the junction of these channel segments forms a rounded interior corner 24 having a radius of curvature substantially the same as the outer radius of curvature of redrawn cup 13b. In general, rounded corner 24 will be configured to provide surface-tosurface contact with at least one quarter of the outer cylindrical surface of the redrawn cup.

The cup is accurately positioned and held snugly in place against rounded corner 24 by means of a vacuum produced by vacuum port 25 positioned at the center of curvature of corner 24.

In general, the vacuum produced by vacuum port 25 will be timed to retain the cup in position until the bottom forming tool, illustrated generally at 26 in Fig. 4, enters the cup. At this work station, a bottom is formed in the cup, resulting in cup article 13c. Following the bottom forming operation, cup 1 3c may be advanced from station 6 to piercing station 7 by an air stream emitted by air jet 27 positioned within rounded corner 24 and directed toward the next work station. It will be understood that the air stream emitted by air jet 27 is timed in relation to the operation of the bottom forming tool 26a.

A straight fourth channel segment 28 connects bottom forming station 6 with piercing station 7.

Channel segment 28 is oriented perpendicularly to channel segment 26 and extends to the left therefrom to form a rounded interior corner 29 located at piercing station 7. Corner 29 is configured to snugly and accurately hold cup 1 3c in position during the operation of a piercing die 30 which places a hole 31 in the bottom of the cup to form a pierced cup article 13d. During the piercing operation, the cup may be held firmly in position by means of a vacuum created through vacuum port 32 positioned at the center of curvature of rounded corner 29. The operation of the vacuum associated with this vacuum port will be timed with the operation of piercing die 30.

Following the piercing operation, cup 13d may be moved through fourth channel segment 28 to trim station 8 by means of an air stream exhausted from air jet 33 positioned at corner 29.

The operation of air jet 33 will be timed with the operation of the piercing die 30.

The remainder of the structure associated with piercing station 7 is conventional in nature.

Final or trim station 8 includes a stop member 34 positioned medially at the end of channel segment 28, together with a rounded surface 35 configured to abut a portion of the outer cylindrical surface of the cup article received from work station 7. A vacuum port 36 is operated in synchronism with the trimming tool 37 to hold the cup firmly against the stop member while the trimming tool descends into the cup. After the tool has entered the cup, stop member 34 is retracted in the direction of arrow 38 so that the flange 39 on cup 1 3d may clear surface 35, permitting the cup to drop downwardly axially of itself to the position shown in dashed lines in Fig. so that the flange may be removed. This results in the finished cup 13e which falls by gravity to a conveyor 40 by which the finished article may be removed from the apparatus.

While for purposes of an exemplary showing, only the operation of a single tooling lane have been described, it will be understood that all tooling lanes 2 may be operated simultaneously to effect the operations described.

It will be understood that various changes in the details, materials, steps and arrangements of parts, which have been herein described and illustrated in order to explain the nature of the invention, may be made by those skilled in the art within the principle and scope of the invention as expressed in the appended claims. For example, while for purposes of an exemplary showing adjacent channel segments are oriented perpendicularly to each other, it will be understood that they may be disposed at any desired angular orientation. For example, as illustrated in dashed lines in Fig. 2, the angle between first channel segment 1 6 and second channel segment 19 may be greater than 90 , imparting a zig-zag shape to channel 15. This may be particularly useful when the diameter of the cup is to be reduced during the operation at the associated work station. In this instance, positioning of the cup is facilitated by the restricted entrance way to the succeeding channel segment. After the diameter of the article has been reduced, it may easily pass into channel segment 19 to the next work station.

Claims (27)

1. in an apparatus for manufacuring cup-like articles of the type having a plurality of spaced work stations for performing a series of successive operations on the articles, said stations being connected by a channel for transferring articles from one work station to the next, said channel being formed by a plurality of angularly disposed channel segments forming interior corners at their junctures, said work stations being located at said junctures, means for holding the articles snugly against an interior corner during the operation of the operation at the associated work station, and means for advancing the articles from station-tostation after each operation.

2. The apparatus according to claim 1 wherein each of said channel segments is straight.

3. The apparatus according to claim 2 wherein said channel segments are substantially perpendicular to each other.

4. The apparatus according to claim 2 wherein one or more pairs of adjacent channel segments intersect to form interior angles greater than 900.

5. The apparatus according to claim 1 wherein said interior corners form rounded surfaces for snugly holding cylindrical articles.

6. The apparatus according to claim 1 wherein said holding means comprises vacuum means positioned at each corner for holding an article snugly thereagainst.

7. The apparatus according to claim 6 wherein said vacuum means comprises at least one vacuum port positioned within the corner for drawing the article thereagainst.

8. The apparatus according to claim 7 wherein said interior corners form rounded surfaces conforming to the outer surfaces of cylindrical articles, said port being positioned at substantially the center of curvature of the corner.

9. The apparatus according to claim 1 wherein said advancing means comprises air jet means for pushing the articles from station to station.

10. The apparatus according to claim 9 wherein said air jet means comprises at least one air jet located adjacent each corner directed toward the next corner.

11. The apparatus according to claim 1 wherein the article is maintained at substantially the same diameter at two successive work stations.

12. The apparatus according to claim 1 including means associated with the last work station for discharging the article axially of the article.

13. The apparatus according to claim 5 wherein said corner is configured to make surface-tosurface contact with at least about one quarter of the article surface.

14. In an apparatus for manufacturing cylindrical cup-like articles of the type having a first work station for drawing a cup from a metallic blank, a second work station wherein said cup is redrawn and its diameter reduced, and a third work station for performing an operation on ~he cup without reducing its diameter, a first channel segment joining the first and second work stations, a second channel segment joining said second and third work stations, said channel segments being angularly disposed to each other to form at said second work station an interior corner at their juncture, said corner being configured to fit the outer surface of the article to accurately position the article at the work station, a vacuum port positioned in the corner for holding the cup snugly thereto during the redraw operation, and air jets located at each work station for advancing the cup from one work station to the next along a pass line.

15. The apparatus according to claim 14 wherein said first work station includes means for positioning the article on a pass line after the respective operation.

16. The apparatus according to claim 14 including a terminal work station for performing an operation on the article, a terminal channel segment connecting the previous work station with the terminal work station, a stop member positioned at the end of the terminal channel segment, a vacuum port associated with the stop member for holding the article snugly thereagainst during the terminal operation, an air jet associated with the previous work station for advancing the article from the previous station to the terminal station, and means for moving the article axially of itself from the terminal station.

17. The apparatus according to claim 16 wherein said moving means comprises means for displacing said stop member to permit said article to fall by gravity to a position below the pass line.

18. The apparatus according to claim 17 wherein said terminal station includes means for trimming the article.

19. The apparatus according to claim 18 including a plurality of intermediate work stations located between said second and terminal stations for performing successive operations on the article, each of said intermediate stations being connected to each other and to previous and subsequent stations by channel segmnets forming a continuous channel for transferring articles successively to each work station, adjacent ones of said channel segments being angularly disposed to form at each work station an interior corner, said corners being configured to fit the outer surface of the article to accurately position it at the associated work station, and a vacuum port positioned in each corner for holding the article snugly thereto during the operation at the associated work station.

20. The apparatus according to claim 19 wherein said intermediate stations comprise means for successively forming a bottom in the article and for piercing the article.

21. The apparatus according to claim 20 wherein said work stations are arranged to successively draw, redraw, bottom form, pierce the form bottom, and trim the article, in the order named.

22. The apparatus according to claim 14 wherein said article forms a cylindrical cup and said corners comprise rounded surfaces for making surface-to-surface contact with the cup.

23. The apparatus according to claim 22 wherein the corners are configured to contact at least about one quarter of the cylindrical cup surface.

24. The apparatus according to claim 22 wherein adjacent ones of said channel segments are arranged perpendicularly.

25. The apparatus according to claim 23 wherein said second and terminal stations are adjacent.

26. The apparatus according to claim 22 wherein adjacent ones of said channel segments are arranged to form interior angles greater than about 900.

27. Apparatus for manufacturing cylindrical cup-like articles substantially as hereinbefore described with reference to the accompanying drawings.