CA1040011A - Can trimming apparatus - Google Patents

Abstract

CAN TRIMMING APPARATUS
ABSTRACT OF THE DISCLOSURE
A can end trimmer is disclosed including a main frame, a main rotary shaft mounted for rotation on the main frame and a plurality of self-contained cutter unit assemblies detachably connectable to the main shaft. Each cutter unit assembly includes first and second rotary cutter knives having circular cutting edges with one knife being mounted for movement between a first position having its cutting edge spaced from the cutting edge of the other knife and a second position having its cutting edge overlying the cutting edge of the other knife. A
rotary vacuum chuck is mounted for cam controlled reciprocation toward and away from the cutter members for positioning a can end over the movable rotary knife when the knife is in its first or open position, subsequent closure of the knife trims the can end and subsequent opening of the knife permits the hol-der to retract the finished can from the cutting position; a unique stripper ring discharges the scrap ring to a separate re-ceiving area. Finger discs mounted on the main shaft provide unique work handling functions for removing unfinished cans from an infeed means and positioning the cans for engagement by the vacuum chuck and for aiding in discharge of finished cans to an outfeed means. Control means for the cutter unit is supported by the main shaft or frame and the entire cutter unit can be removed for maintenance or placement with minimum difficulty. Another embodiment of the invention employs a central cutter knife and planetary cutter knives movable to overlying relation with respect to a cutting edge of the central knife for effecting the trimming of can ends positioned over the planetary knife members by automatic handling means similar to that of the first embodiment.

Description

1 10~0011 ~ACXGROUND OF Tl~ INVENTIOW
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The present invention is in the field of cuttin~ and trimming apparatus and is particularly directed to an improved apparatus for trimming the ends of cylindrical work pieces such as cans.
In the manufacture of metal cans, it is conventional practice to form an unfinished can or container of cylindrical configuration consisting of a bottom and a cylindrical side wall which is open on the top end. Such unfinished can members can be formed by a variety of processes such as drawing and ironing to provide the unfinished container. Subsequent to the formation of the uninished container, it is necessary to trim the upper ; end of the container to achieve a container of a fixed desired height and having a smooth upper edge termination. It is essen-tial that the upper edge termination o~ such containers be essentially flawless since the upper edge is subsequently subjec-ted to an outward flanging process for enabling the connection of a top to the container. Any burrs, cracks or the like can prevent obtainment of a qood seal between the top and the can in the flange area. ' Numerous devices have evolved for the purpose of trimming the ends of unfinished containers. However, all of the presently known devices employed in trimming can ends suffer from a number of deficiencies for which adequate solutions have never been previously advanced. For example, some prior art devices have initially positioned the unfinished can on a mandril for cutting by an external cutter moved inwardly into engagement ., _ .;
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... 1040011 ¦ with the outer surface of the can and traversed about the peri-¦ phery of the can for effecting the cutting of the can end. Sub- _ ¦ stantial problems are encountered with devices of this type due , ¦ to the fact that the cutting operation frequently results in 5 ¦ burrs, cracks or other imperfections in the upper edge portion ¦I'of the container wall which are enlarged during the subsequent i ¦ flanging of the can ends priox to application of a top to the ¦ can body.

Various other devices have evolved in an effort to lO ¦ achieve a more perfect can trimming operation such as devices employing a circular knife member having an inner cutting edge with the can being positioned inside the knife member followed ¦ by the subsequent positioning of an internal knife inside the l can which is then moved outwardly to effect a cutting operation 15 ¦ with the external periphery of the knife member. Devices of , this type are frequently complicated,and the exact positioning of the knife members is of critical importance if a satisfactory cut is to be achieved.
A primary problem,with many of the prior art devices resides in the fact that the cutter members, which are the heart of every cuttin~ machine, are integrally built into the machine and any failure of any part of the cutter means requires a time consuming disassembly of substantial portions of the machine resulting in undesirably long periods of down time for such machine,s.
Probably the greatest drawback of the prior known devices is that the cutting members or knives require time con-suming adjustment and alignment procedures and the knives are .

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¦ frequently damaged duc to misalignment or misadjustment.
¦ ~nother deficiency shared by the prior art machines ¦ is that they are frequently extremely complicated due to the l complex plural-stepped positioning of the can members prior 5 ¦ to, during and after a cutting operation. Not only does such ¦ complexity increase the initial cost of the machine, it also increases maintenance expense and down time t~ the detriment of the owner.
l The subject invention provides a reliable and trouble-free can trimmer device which is relatively simple in constructionoperation and maintenance. All parts of the mounting, driving and actuation functions for the cutter units are part of a removable unit that can be easily removed from the machine for maintenance and adjustment. While one cutter unit is being worked upon, another unit can be positioned on the machine in less than a minute so that there is no substantial down time for the particular machine.
Another extremely significant achievement of the present invention resides in the fact that the unique removable cutter units enable a sharpening of the rotary cutter members and replacement in an exact position with respect to each other without any necessity for time consuming adjustment in the machine. The accurate posltioning of the cutter members enables the cutter members to be operating for much longer periods of time without making imperfect cuts.

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¦ Therefore, it is the primary object of this invention ¦ to provide a new and improved apparatus for trimming can ends.
¦ Achievement of the foregoing object is enabled in 5 ¦ the preferred embodiment by the provision of a main rotary shaft extending horizontally between bearing supports with first and ¦ second cutter units being positioned on the shaft in a manner which enables an easy removal and replacement of the cutter units I in the event of any malfunction. Each cutter unit includes a lO ¦ pair of shafts geared together and each supporting a rotary cutter knife on an outer end externally of the frame of the cutter unit.
¦ One of the knife shafts is mounted for movement with respect to the other on a limited arcuate path so that the cutter Xnives can I be moved between one position in which their peripheries overlie 15 I each other and an open position in which their peripheries are ¦ spaced apart to enabls the insertion or removal of a can member.
¦ When a can is insexted over the cutter members, one cutter knife ¦ i9 received inside the can and the other is received externally I of the can.
20 ¦ Each cutter unit includes a cutter knife actuator positioned adjacent an actuator pin timingly reciprocated by a ¦ cam follower during rotation of the main shaft. Oscillation of the cutter actuator arm serves to move one of the cutter knives into the cutting position overlying the other knife at desired time intervals during a cycle of operation. In one embodiment, the knife members are removable,relatively thin discs having either single or double cutting edges. Additionally, each cutter unit includes a power input gear engageable with the ~ r - , - -=, . ~ ~ .
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; ~4C31~1 internal teeth of a ring gear encircling the main shat and rotating with respect to the main shaft so that the cutter - _ members are drivingly rotated. However, the cutter units can be removed from the main shaft by simply removing three threaded bolt or pin members and a lifting of the unit from the main shaft.
A new cutter unit can then be repositioned on the main shaft :,i in a very short time and operation of the device resumed while the initially removed cutter unit is repaired or adjusted as required by the particular circumstance of its removal.
Another feature of each cutter unit resides in the provi.sion of a plurality of can positioning pins positioned about one of the cut~er knives and extending forwardly axially parallel to the shaft on which that knife is mounted. Unfinished cans are moved forwardly by a vacuum chuck over the posi~ioning pins all of which are received on the interior surface of the , open end of the can. A stripper ring is mounted for reciprocation on the positioning pins and the ring is moved toward the outer end of the positioning pins following a cutting operation to remove the scrap rings from the pin to be discharged into a scrap receiving chute. `
,l Inward and outward movement of a vacuum chuck re-~; ceiving unfinished cans from an infeed conveyor is provided ~y aradial flange type cam by first and second cam followers on the sides of the radial flange with one of the cam followers having a surface with a substantial coefficient of friction so that the cam follower is driven by frictional engagement with the side of the cam. Rotational drive from the cam follower is provided ~o the vacu~ ohuok,so that the chuck is coDt~nuously rotated.

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It is of some importance that the same cam that provides for reciprocation of the chuck toward and away from the cutting knives also provides the rotational drive of the chuck.
- Reciprocation of the vacuum chuck results in connection of the chuck to a source of vacuum at desired portions of each rotation of the main shaft and subsequent disconnection to permit discharge of a completed or finished can member into an outfeed conveyor.
In a second embodiment of the invention, the cutting operation is effected by a main central rotary cutter knife and orbiting planetary cutter members simultaneously cooperating with the main cutter member. The orbiting cutters are recipro-cated radially with respect to the main cutter and can ends are positioned between the main cutter knife and the orbiting knife ; surrounding the orbiting knife by handlinq means similar to that discussed previously with respect to the first embodiment. The orbiting knife is then moved inwardly so that its cutting edge overlies the cutting edge of the main knife as the entire assembly is rotated thxough a substantial arcuate path. Rotation of the cutting knives serves to trim the scrap ring from the end of the containers which are then removed from the cutting position sub-sequent to opening of the knife members and are discharged into an outfeed conveyor. In the second embodiment, only three cutter members are employed for providing two cutting stations due to the cooperation of the main cutter with both of the planetary `~ cutter knife members.
Broadly stated, therefore, the present invention is directed to a can end trimmer apparatus for trimming the open B l js/ .~

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, ' ' . ' 1~4(30~1 cylindrical end of a cylindrical can having a closed opposite base end, the apparatus comprising: a fixed main frame, main shaft means supported for rotation on the main frame, a cutter unit assembly including: a first rotarv knife having a circular cutting edge; a second rotary knife having a circùlar cutting edge and positioned adjacent the first rotary knife; selectively operable knife actuator means for moving the second rotary knife between a first, or cutting, knife position in which the circular cutting edges of the rotary knives overlap and a second, or non-cutting, knife positi.on in which the cutting edges are spaced apart and do not overlap; power transmission means drivingly connected to the first and second rotary knives for enabling rotation of the knives; drive means for drivingly rotating the main shaft means; a source of power drivinglY engaged with the power transmission means when the cutter unit assembly is in operative position for driving the rotary knife members; can holder means mounted on the main shaft adjacent the cutter unit assembly for movement between a first holder position in which a can supported by its base end on the can holder has its open end spaced from the knife members and a second holder position in which the open end of a can on the holder encloses one of the knife members with a portion of the can wall extending between the rotary knife members when the second knife is in the second or non-cutting position; cyclically operated knife control means engageable with the knife actuator means for causing the knife actuator means to position the second rotary knife in either the first or second knife positions during desired discrete portions of each revolution of the main shaft; and cvclically - 8a -ljS/~'`;,~

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operated can holder positioning means operated in fixed timed relationship with the cyclically operated knife control means for moving the can holder to the second holder position at a time when the second knife is in the second knife position and retaining the holder in the second holder position while the second rotarv knife first moves to the first knife position to effect cutting of an end portion of a can in the can holder from the remainder of the can and then moves back to said second knife position and for moving the can holder to the first holder position subsequent to the last-mentioned movement of the second rotary knife to the second knife position.
. A better understanding of the subject invention will be enabled when the following written description is read in conjunction with the appended drawings which will now be described.

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D~SCRIPTION OF TIIE DRAWINGS

:I FIGURE 1 is a front elevation view of the preferred embodiment of the invention;
FIGURE 2 is a sectional view taken along lines 2-2 S of Figure l;
FIGURE 3 is an end elevation view of the preferred embodiment;
FIGUgE 4A is a longitudinal section with parts broken away for clarity of one end portion of the preferred embodi ment which joins Yigure 4B at line 4A;
FIGURE 4B is a longitudinal sec~ion with parts removed of the remaining portions of the preferred embodiment extending from line 4B of Figure 4A;
. FIGURE S is a sectional view taken along lines 5-5 of Figure ~A;
. FIGURE 6 is an exploded perspective view of the prim-ary operative components of the preferred embodiment;
. FIGUXE 7 i9 a sectional view taken along lines 7-7 of Figure 4A~
FIGURE 8 is a sectional view taken along lines 8-8 of Figure 4B 7 FIGURE 9 is a sectional view taken along lines 9-9 of Figuro 8; ' FIGURE 10 is a sectional view taken along lines 10-10 of Figure 85 FIGURE 11 is a sectional view taken along lines 11-11 of Figure 6 illustrating the can end rotary cutter knives in a closea condition;
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FIGURE 12 is a sectional view similar to Figure 11 but illustrating the can end rotary cutter knives in an open non-cutting position;
FIGURE 13 is a sectional view taken along lines 13-13 of Figure 6;
FIGURE 14 is a perspective view of a knife support rocker block cutter blade support of the cutter unit;
FIGVRE 15 is a partial section of an alternate cutter construction;
10 FIGURE 16 is a bisecting section of alternate forms of removable cutter blades usable in the cutter of Figure 15;
FIGURE 17 is a pictorial timing chart illustrating various steps in a cycle of operation of the preferred embodiment;
and 15 FIGURE 18 is a front elevation view of a second embodi-ment of the invention.
DESC~IPTION O~ THE PREFERP~D EMBODIMENT
Attention is initially invited to Figure 1 which illustrates a preferred embodiment of the invention which com-prises a main support frame formed of a base or pillar plate 20having vertically extending connector flanges 22 and 24 extending upwardly from its upper surface. A first vertical support pillar plate 26 is connected to the vertical connector flange 22 and a second vertical support pillar plate 28 is fixedly connected to the second vertical connector flange 24 by nut and bolt members 30 and 32 respectively. All of the operative components of the preferred embodiment are supported between the first and second vertical support pillar plates 26 and 28 by rotary bearing means 30 ~Fig. 4A~ mounted in first vertical support pillar plato 30 26 and rotary bearing means 32 mounted in the second vert~cal -~upport pillar platc 28 ~Fig. 4B).
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l supported by rotary bearing members 30 for rotation and a sleeve i drive gear 38 is fixedly connected to the end of the main rotary _ sleeve 36 for providing input drive to the sleeve in a manner and , for purposes that will become apparent hereinafter. Additionally, the other or opposite end of sleeve 36 is provided with a ring gear 40 fixed to sleeve 36 by threaded pin bolts 41. Ring gear 40 has a continuous circular array of inwardly facing teeth which provide an output drive for a cutter unit to be described hereinafter.
Rotation of the main rotary sleeve 36 is effected through gear means best illustrated in Figure 4A and Figure 5 including an idler gear 42 meshing with gear 38 and coaxially mounted for unitary rotation on support means 44 with a smaller coaxial gear 46. Gear 46 meshes with an idler gear 48 ~Fig. 5) which also meshes with a primary shaft drive gear S0 keyed to the end of a main shaft 51 ~Fig. 6) on a cylindrical end portion 54 of the main shaft with a threaded shaft portion 55 being im-mediately inward of end portion 54. Additionally, a main power ~.nput gear 56 i9 also keyed to the main shaft 51 on the cylindri-cal end portion 54 with a separator ring 58 providing properspacing between the two gear members 50 and 56 and with a conven-tional retainer means 60 maintaining the gear 56 on the end of the shaft in an obvious manner.
It shbuld be noted that rotation of the main input gear 56 in a clockwise direction will result in rotation of the main shaft 51 in a clockwise direction; however, the main rotarY
sleeve 36 will rotate in a counter-clockwise direction. The ¦relative ~o~ on ~etween the ~in ~leeve 31i and the ~ _ _ . . _ ~.

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~.~4~:D09~ 1 i5 enabled by virtue of the fact that the only connection betwcen the main sleeve and the main shaft is by rotary bearing means 62 _ (Fig. 4A) externally engaging the interior of the sleeve 36 and internally engaging the cylindrical portion 64 of the main shaft i51.
Support for the end of main shaft 51 opposite the end to which the main power input gear 56 is connected is pro-: vided by the rotary bearing means 32 mounted in the second ver-tical support pillar plate 28 and engaging a cylindrical bearing section 66 of the main shaft as best shown in Figure 4B. Bearing retainer rings 70 and 72 are provided on opposite sides of the second vertical support pillar plate 28 for retaining bearing 32 in position as best illustrated in Figure 4B. ~dditionally, a fixed cylindrical work piece positioning control cam 74 having a radial cam flange 76 is bolted to the vertical pillar plate ' 28.
¦ Main shaft 51 includes a gear and cam mounting oblate portion 79, relatively large diameter cutter unit mounting portion 80 and a similar large diameter wor~ piece feed holder mounting portion 81 with a central smaller diameter section 82 being pro-vided between the portions 80 and 81. The upper extent of the shaft a~ viewed in Figure 6 is defined by planar surface 84 and a longitudinally extending recess, generally designated 86, ex-tends downwardly from theplanar surface 84 and enables the mount-

2 ing of various components on the main shaft for purposes to be .discussed.

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It should be understood that the main shaft 51 is symmetrical about a horizontal plane passing through its axis so that the shaft 51, if rotated 180, would have the same exact appearance as the shaft as illustrated in Figure 6. Moreover, S the main shaft 51 is also symmetrical with respect to a vertical plane through the axis of the shaft..
A center web or floor 100 extends substantially the entire length of the relatively large diameter cutter unit mounting portion 80 . A thicker center floor web 102 is provided in the central portion 82 and the work piece feed holder mounting portion 81 for defining the inner extent of the longitudinally extending recess 86. Additionally, slide bearing mounting shoul-ders 104 and 106 are provided on each side of the recess 86 in the end of the cutter unit mounting portion 80 adjacent the cen-tral portion 82 and similar planar mounting shoulders 108 and 110are provided at the extreme end of the work piece mounting portion 81; a relatively long cylindrical shaft section extends between the portion 81 and the smaller cylindrical bearing portion 68.
A cam mounting fitting plate 114 is affixed to the inner surface of the first vertical support pillar plate 26 and a cutter control cam 116 having an outer peripheral cam surface 117 is mounted on the cam fitting plate 114 as best illustrated in Figures 1 and 4A. A cam follower support flange 118 radially extending from main shaft 51 ~Fig. 6) has a central aperture 120 matingly fitted over the oblate portion 79 of the main shaft to which it is fixedly connected by bolts or threaded pins received .
in the end wall 81 of the relatively large diameter cutter unit portion 80. A pi~ot shaft 124 is mounted to transversely extend through the radial cam follower support flange 118 and a bore in .. _ ' ~ 1 ' ~

. a bracket 125 fixed to flange 118. ~ cam follower support arm . 126 is mounted on the end of the pivot shaft 124 and supports a . cam follower roller 128 normally biassed toward the cam surface 117 by compression spring means 130 extending between support arm 126 and a lug 131 fixed to support flange 118. Cam follower . roller 128 is in radial alignment with the outer periphery of the cutter oontrol cam 116 and travels about the cam surface 117 . as the support flange 118 rotates with the main shaft Sl. Cam i surface 117 is contoured so as to oscillatingly pivot support .
13, arm 126 and shaft 124 for providing pivotal movement of a cutter actuator arm 132 fixedly connected to ~e end of shaft 124 oppo-site cam follower support arm 126 as best illustrated in Figure 6.
j A threaded adjustable abutment lug 136 is adjustably mounted in the upper end of the cutter actuator arm 132 so as to be radially ~; adjustable for a purpose to be discussed hereinafter.
¦ In the preferred embodiment, two identical removable cutting units, each generally designated 140, are mounted on the main shaft 51 on diametrically opposite sides of the main shaf l as will be apparent from inspection of Figures 1 and 7.
2~¦ Additionally, two work piece handling units, gener-i ally designated 150, are mounted on diametrically opposite sides , of the main shaft Sl with eachofthe work piece handling units lS0 l being associated with one of the removable cutter units 140 for I reaeiving raw work pieces 354, moving the raw work pieces into 2~ position to have one end trimmed therefrom by the cutter unit and .~ubsequently removing the trimmed work piece 354' for discharge rom the apparatu~.

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Each of the removable cutter units includes a rigid box-frame 160 the main elements of which include first and second side walls 162 and 164 (Figs. 11 and 12), first and second oot plates 166 and 168 separated by a downwardly extending rec-tangular channel comprising vertical side plates 170 and 172and a bottom plate 174. ~he ends of the box-frame 160 comprise a first end wall 176 and second end wall 178. A cap plate 179 connected to the top edges of side walls 162 and 164 and end walls 176 and 178 completes the box-frame 160.
Box-frame 160 provides support for a number of intern-al components including a first cutter shaft 182 (Fig. 4A) sup-ported for rotation by roller bearings 177 in the end wall 176 and a sleeve bearing 183 in rectangular block lug 184 extending outwardly from the second end wall 178. A first rotary cutter lS member 186 having a circular cutting edge 187 is keyed for ro-tation on the shaft 182 and has an inner radial face 188 in abutting engagement with a radial positioning flange 190 of shaft 182 near the end of the shaft 182. Rotary cutter 186 is held in position on the end of the shaft by retainer means 192.
2 A cutter drive input gear 194 is keyed to the outer end of shaft 182 cxternally of box-frame 160 and a gear 196 is keyed to shaft 182 on the interior of the box-frame 160 in a position best illustrated in Figure 4A.
A second rotary cutter knife 200 haviny a circular 2 cutting edge 201 is mounted on the end of a second cutter shaft 202 supported for rotation by a rocker block 204 (Fig. 14) positioned within the confines of the box-frame 160. Rocker block 204 is mounted for pivotal movement on a pivot shaft 206 ~ .

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~D4(3~)~1 extending betwcen the end walls 176 and 178 of the box-frame 160.
. Rocker block 204 includes first and second leg portions 208 and 210 joined by a base portion 212 through which the pivot shaft 206 extends. Leg portion 208 is apertured to provide support for roller bearings 209 supporting one end of the second cutter shaft 202 and a cylindrical extension 214 extending perpendicular-ly from the side of second leg 210 includes a sleeve bearing 216 supporting the other end of the second cutter shaft 202 as best illustrated in Figure 4A. Additionally, a vertical lug 218 extends upwardly from the corner of the rocker block 204 and includes an aperture 220 in which a coil compression spring 230 .. is positioned between lug 218 and wall 164 for urging the rocker block in a counter-clockwise direction as viewed in Figure 12.
,.~ A wear plate 232 ~Fig. 13) is provided in a depression 1~ aligned with the spring 230 in alignment with a low-friction rol-ler 234 mounted in the end of a push rod 236. Push rod 236 is ,supported in a slide bearing 238 mounted in an aperture in the side wall 162 and includes a positioning flange 239 abutting against the end of the slide bearing 238. The force of spring 230 urges push rod 236 to the left as viewed in Figures 11 and 12 in a obvious manner. The outer end of the push rod 236 is rounded as '~' at 240 for low-friction engagement with the end of abutment lug `~,. 136 as shown in Figure 7.
;~ A generally circular fitting plate 242 is attached to thee~ternal surface of the end wall 178 coaxially,with respect to an opening in the wall and a plurality of work piece '¦¦ positionin ins 244 extend outward1y fro~ the fitting plate 2~2 ¦ ¦

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and a stripper ring 245 having diametrically opposed radial actuator pins 2451 is mounted for reciprocation on pins 244. Pins 244are received on the interior of the open end of a cylindrical work piece in a manner and for a purpose to be discussed in detail hereinafter.
It should be noted that the fitting plate 242 is provided with an aperture 246 throu~h which the cylindrical bearin~
support extension 214 of rocker block 204 extends with the aper-~
ture 246 being of larger size than the outer periphery of the cylindrical bearing support extension 214 to permit pivotal movement of the cylindrical extension 214 within the aperture between the limit positions illustrated in Figures 11 and 12.
The removable cutter units 140 are positioned on the main shaft 51 with the lower surfaces of foot plates 166 and 168 resting on the planar upper surface 84 and the vertical side plates 170 and 172 extending downwardly into the longitudinal recess 86 above the center floor web 100. Machine screws or other equivalent members hold the cutter units fixedly in position on the main shaft.
A gear 248 is keyed to shaft 202 to mesh with the gear 196 so that driving rotation is imparted to shaft 202 via ring gear 40, gear 194 and gear 196 as shaft 51 rotates with respect to main rotary sleeve 36 in a manner~that will be obvious from inspection of Figure 4A. The second rotary cutter ~nie 200 is urged axially outwardly by a compression spring 250 against a radial abutment surface 254 of a retainer 256 threadably received in the end of the shaft 202. Surface 254 engages and is conse-quently accurately positioned by the end of the shaft 202 and so as to achieve an exact positioninq of the knife member 200 both . _ ~ ' .

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with rcspect to the shaft 202 and the first rotary cutter ~nife 186 which is positioned against the radial surface of the position ing flange 190 on shaft 182. Consequently, an exact positioning of the knife members with respect to each other is enabled in the cutter unit per se. It is of great advantage that the entire : cutter unit can be removed from the machine in the event of any malfunction of any part of the cutter unit and replaced in an expeditious manner without any substantial disassembly of any parts of the cutter support or drive components.
More specifically, each cutter unit 140 is positioned with the ~wer surface of the foot plate 166 and 168 resting on planar surface 84 and the elements between the vertical side . plates 170 and 172 extending downwardly in the longitudinal slots `?; 86 above the floot plate 100. As thus positioned, the cutter lS units 140 are he~d in position by threaded bolts or pins 256 received in apertures 258 in the main shaft 51. As thus positioned on the main shaft 51, the cutter unit drive gear 194 .' i9 in mesh with the ring gear 40 and rotation of the main shaft 51 conseguently results in rotation of the cutter ~nives 186 and 200 via shaft 182, gear 196, gear 248 and shaft 202 in a manner that will become apparent from inspection of Figure 4A. It should also beroted that the rounded end 240 of the push rod 236 is positioned in engagement with the adjustable abutment lug 136 on the cutter actuator arm 134. Conseguently, rotation of the shaft 51,radial cam follower support flange 118 and cam follower 128 etc. will traverse the cam follower 128 about the periphery of cam surface 117 to provide oscillation of pivot shaft 124 to ! 18 , ........................ , _ .

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reciprocate the push pin 236 botween extreme Fositions of movcment illustrated in Figures 11 and 12 to move the rotary cutter knives _ 186 and 200 between engaged and disengaged positions in timed relationship to the movemen~ of work pieces between the ¦ 5 cutter knives by the work piece handling units 150.
The construction of the identical work piece handling :' UAitS 150 will now be discussed in detail with initial attention being invited to Figure 6 which illustrates their main components.
Primary support for the components is provided by a bushing block 260 having side flanges supported on shoulders 108 and 110 and held in position by threaded pins or the like 264 ~Fig. 1). It should be understood that there are two identical work piece handling units 150 oriented on opposite sides of the main support shaft Sl and each one of which is associated with a removable cutter unit 140.
, A cylindrical slide bearing 264 is provided in each of the bushing blocks 260 for supporting a slide sleeve 266 for ~xial reciprocation therein. A work piece drive shaft 268 i mounted for rotation on bearings 270 internally of sleeve 266.
Additionally, a manifold block 272 i9 sealingly engaged with a central portion oP the shaft 268 and includes a circumferential ring-shaped chamber 274 communicating with a radial bore 276 iA
shaft 268 which has its inner end communicating with an axial bore 278 extending to the outer or left end of shaft 268 as viewed in Figure gB. A circular vacuum chuck 280 is mounted on the end of the shaft 268 and has an aperture 282 communicating with the axial bore 278.

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l ~ Y-shaped slide plate 300 tFig. 6? extends forw~rdly ¦ from beneath the lower end of the slide sleeve 266 and includes ¦ forward guide plates 302 received in inwardly facing slots 304 of ¦ slide bearings306 mounted on shoulders 104 and 106 of the main 5 ¦ shaft 51 ~Fig. 6). A stripper ring actuator link 308 extends ¦ upwardly from each of the guide plates 302 ~only one of which ¦ links is illustrated in Figure 6 for purposes o~ clarity) and ¦ has an open slot 310 at its upper or outer end received on one ¦ of the actuator pins 245' of the stripper ring 245 so that re-10 ¦ ciprocation of the actuator links 308 will move the stripper ring ¦ 245 along the work piece positioning pins 244 for a purpose to be ¦ discussed.
¦ Timed reciprocation of the slide sleeve 266 and its ¦ associated parts including a work piece cradle 312, actuator 308 lS etc. i9 achieved by virtue of operation of first and second cam followers 31~ and 320 carried by a bracket 330 fixedly connected to the end of sleeve 266 opposite the vacuum chuck 280. The ~irst cam follower roller 318 is keyed to a shaft 332 to which a bevel ~ear 334 is also fixedly connected. ~evel gear 334 is in ~0 mesh with a second bevel gear 336 keyed to the work piece of shat 268. The surace of roller 318 has a high coefficient of riction and movement of the roller with respect to the side of cam 76 consequently drivingly rotates the roller, shaft 332 and gear 334 to drive the gear 336 and work piece drive shaft 268 2S and associated vacuum chuck 280. It will ~e seen that the curva-ture of cam 76 will shift sleeve 266 etc. inwardly and outwardly of the slide bearing 264 in the bushing block 260 as the main shaft rotates with respect to the fixed cam 76. The two extreme positions of the slide sleeve 266 etc. are illustrated by the 30 ¦ upper and 1 r sleeves ln ~lgurc 4~.

1~ I ~ ~ '., I 1~0~1 It is necessary that the vacuum chuck 280 be con-nected to a source of vacuum during a substantial portion of a cycle of operation. Achievement of the foregoing requirement is enabled by the provision of an axial bore 340 extending from the endc the main shaft 51 and communicating with a transverse bore 342 which is plugged at both ends and which communicates with passageways 3~6 extending between the respective shoulders 108 and 110 on the upper and lower sides of the main shaft 51 as viewed in Figure 6. The passageways 346 extend upwardly through~
the bushing block 260 (Fig. 4s) and slide bearing 264 to com-municate with an elongated chamber 348 provided in each of the slide bearings 264. A radial bore 350 in sleeve 266 provides communication with the ring-shaped chamber 274 as shown in Figure 4B.
15 ¦ When the sleeve 266 is in the position of the upper-most sleeve illustrated in Figure 4s, vacuum introduced through any conventional rotary coupling fitting C to the axial bore 340 is conveyed ViA elements 340, 342, 346, 348, 350 and 274 to the ra,dial bore 276 in drive shaft 268 so as to apply vacuum to axial bore 278 and the aperture 282 on the face of the vacuum chuck 280. However, movement of the sleeve 266 to the right from the position of the upper sleeve illustrated in Figure 4B to the position illustrated by the lower sleeve 266 in Figure 4B serves to position the radial bore 350 in sleeve 266 beyond the extent of the elongated chamber 348 in communicationwith the external-atmosphere so as to ~issipate any vacuum in the vacuum chuck in an obvious manner.
Work piece 354 comprising cylindrical members closed ' ' 21 ~
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at one end and having an unfinished opposite e~d 356 are fed to the pre~erred embodiment to have the unfinished end 356 neatly cut from the wor~ piece by knives 186 and 200 to provide a result- _ ant end construction to which a top can be subsequently permanent-ly affixed. ~eans for feeding and discharging the work pieceswill now be discussed.
An infeed conveyor 358 (Figs. 1 and 5) receives the unfinished work pieces 354 from any conventional supply source such as another eonveyor or the like. Trimmed and finished work pieces 354' are discharged from the apparatus by a discharge con-veyor 360. Support for both the infeed conveyor 358 and the out-feed or discharge conveyor 360 is provided by first and second vertical standards 362 and 364 extending upwardly from the base plate 20 to which their lower ends are connected.
Infeed eonveyor 358 includes an upper transverse , plate 372 and a lower transverse plate 37q extending between and connec~ed to the vertical standards362 and 364. Lower guide rails 376 are connected to the lower transverse plate 374 and upper guide rails 378 are connected to the upper transverse plate 372 with a pivot shaft 380 ~Fig. 8) extending between the upper rails 378 for pivotally supporting the inner ends of first and second arcuately curved can infeed guide means 382 medially joined by a transverse angle 384 in which an adjustment lug 386 is threadably received. The lower end of thè adjustment lug 386 rests upon a fixed stop member 388 on the frame which limits the extent of downward movement of the infeed guide members 382 about pivot shaft 380 in an obvious manner. Side plates 390 and 392 pro vide a lateral axial positioning of the unfinished work pieces in the form o~ cans 354 fed downwardly between the rails 376 and 378.

~_ ~_~
;l .

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~
~-l ~04(~0~1 i Discharge conveyor 360 is also supported between the vertical standards 362 and 364 and includes lower floating guide rails 3~4 supported on a transverse plate 396 (Fig. 8) extending between the vertical standards 362 and 36~ and having curved outer ends 394'. A plurality of pins 398 are axially positionable in bores in the transverse plate 396 and have their inner ends fixedly connected to the lower guide rails 394.
A coil compression spring 399 us provided on each of the pins 398 so that the pins are urged downwardly to hold the rails 394 in the position illustrated in Figure 8; however, it will b~
apparent that the lower rails 394 are flexibly supported and are capable of some limited movement as they are engaged by cans fed onto their outer ends.
Discharge conveyor 360 also includes a pair of upper i5 guide rails 400 supported on a transverse plate 402 and have curved outer ends 404. The upper guide rails 400 are similarly 1exibly supported by pin and spring members in the same manner as the lower guide rails 3~4. Cans received between the rails 400 and 394 are conveyed away from the inventive apparatus to another conveyor or the like as re~uired by the particular manufacturing operation.
Means are provided on the main shaft 51 for removing the lowermost unfinished work piece 354 from the infeed conveyor 358 to be received by the vacuum chuck 280 etc. during the can end 2 trimming operation. Additionally, the same means employed for removing the lowermost can from the infeed conveyor 358 also serve to rapidly eject a finished can 354' from the rotating work sup-port means 312, 280 etc. into the discharge conveyor 360 in a man-.. ' , '~ , '.

~ - _ ,r ner to be discussed.
More specifically, parallel fingcr discs 406 are mounted on each end of mounting blocks 408 which are fixedly connected to the arcuately curved outer edge surface 82' of the central portion 82 of the main shaft 51 as shown in Figure 6. Each disc of each pair of discs on each mounting block mutually cooperate with each other. The disc pairs are mounted on opposite sides of the main shaft in the central portion 82.
Only one pair of discs is illustrated in Figure 6 for purposes of clarity . Therefore, it will be seen that a total of fo~r finger discs 406 are employed on the shaft 51.
Figure 8 illustrates one finger disc of each of the finger disc pairs. Each finger disc 406 has an arcuately curved outer peripheral surface 410 with the center of curvature of lS the surfaces 410 for the upper or righthand pair of discs in Fiyure 8 being positioned above the axis 51' of the main shaft 51 and the center of curvature of the surfaces 410 of the lower or lefthand disc being positioned below the axis 51' as will be evident from inspection of Figure 8. Each of the discs 406 includes a leading (as rotated in the direction of arrow 414 in Figure 8) work piece engaging sufface 412 and a trailing surface 413 . It will be noted that the dual function surface 412 will . engage the lowermost can in the infeed conveyor 358 to remove that can from the conveyor as tke apparat~s rotates in the direc-2 tion of the arrow 414 in Figure 8 and the same surface ql2 also serves to eject the finished can 354' onto the outfeed conveyor : 360. It should be noted that the arcuate surface 410 trailing . behind the dual function work piece engaging surface 412 servcS

'~_ ~ ~ . , .. ~ _ ~ ~ --1(~4(30~
to prevcnt the next can inthe infeed conveyor from moving from the conveyor unit until such time as the trailing surface 413 has rotated past alignment with the lower end of the infeed conveyor 358.
Additionally, a scrap removal chute 416 having side walls 418 and 420 is positioned adjacent the discharge conveyor for receiving scrap rings 354" trimmed from the can wor~ piece.
Side wall 420 has a sharp forward edge 428 for aiding in receipt of the scrap rings 354''.
A complete cycle of operation of the preferred embodiment as illustrated in Figure 17 will now be di~cussèd with primary reference being to Figures 7, 8 and 17. The cycle begins with the elements rotating in the direction of arrow 414 as a lowermost can on the infeed conveyor 358 moves from the trailing portion 413 of the arcuate surface 410 of one pair of finger discs 406 downwardly in ront of the following work piece engaging surface 412 of the other pair of finger discs. For reference purposes, various angular positions are illustrated in Figure 17 with the various positions being designated in roman 2 numerals.
In position I, the surface 412 is engaging the can ~ust deposited on the work piece cradle 312 as discussed above vacuum chuck 280 is in its retracted position and the aperture 282 is vented to atmosphere with no vacuum being applied theretO.
2 ~dditionally, in position I, the knife members 186 and 200 are in their open position as shown in Figure 5 by virtue of the fact that the cam follower 128 is on a high portion of the cam surface 117. ~ ' - ~

10~

~s the appa~atus rotates fxom position I toward position II, continuously rotating vacuum chuck 280 moves forward to position radial bore 350 in communication with the elongated chamber 348 to which a constant vacuum is being applied by pre-viously discussed conduits 340, 346, etc. Consequently, vacuum is supplied to the aperture 282 in the face of the vacuum chuck and the unfinished work piece adjacent the vacuum chuck is pulled into engagem~nt with the ace of the chuck to initiate rotation of the can as the chuck continues to move to the left toward the open cutters 186 and 200. Continued movement of the chuck to the left moves the end of the unfinished container 354 into the dotted line position in which the upper cutter knife 200 is positioned on the interior of the unfinished work piece as symbolically illustrated in the uppermost portion of Figure 15.
;. 15 At the termination of 70 of rotation at position II, the vacuum chuok has moved to its forwardmost position and during the next 10 of rotation to position III, the upper knife member 200 is rapidly moved downwardly to the cutting position as illustrated pictorially ad~acent angular position III in Figure 17.
It should beroted at this juncture that Figure 7 illustrates the upper pair of rotary cutter units 186 and 200 in a closed oondition and the lower pair of cutter units in an open condition for purposes of comparitive illustration. In actuality, cutter units in the position of the upper units ~the twelve o'clock position) would actually be open as figurativelY
. illustrated in Figure 17 and the upper cutter member does not movc . to the lower or closed position until it reaches angular pOSition III iA Figure 17. The upper righthand cam follower 128 illustra-, _ .
.

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.i 0,~
.
ted in phantom in Figure 7 is illustrated in the position that the roller 128 would occupy if the u~per cutter member 200 was in the lower or cutting position as illustrated in Figure 7.
In actuality, the roller 128 in the upper righthand portion of Figure 7 would be riding on the higher part of cam 117 and the cutter member 200 would consequently be in an open pOsition in the same manner as the lower cutter member 200.
Spring 230 must be of substantial size and strength in order to provide effective movement of the cutter member 200 downwardly to the cutting position when the pin 236 etc. is retracted by operation of the cam 128, shaft 124 and cutter actuator arm 134.
An important fact to be kept in mind is that the cutter members 186 and 200 are constantly rotating both in the open and closed positions since the qear teeth or gear members 248 and 196 are of sufficient height to maintain the teeth in mesh when the cutter 200 is in its upper or raised position.
Similarly, the vacuum chuck 280 is continuously rotating by vir-tue of the drive from elements 318, 334, 336 and 268.
Following completion of the closing of the knife members at angular position III, the cutting of the can end is effected during the next 90 of rotation to position IV at which point the cam fol1ower 128 engages rise 117' (Fig. 7) of cam surface 117 to rapidly open the ~nife members by moving the rotarY
2 cutter 200 to the open position as pictorially illustrated adjacn positions IV and V with the opening of the cutter members being completed in approximately 10 of main shaft rotation at pOsition V. ~ , ~` ~

i, Upon completion of the opening of thc knife membcrs, the cam 76 begins retraction of the slide sleeve 266, vacuum _ chuck 280 and Y-shaped slide plate 300 away from the cutters ~to the right as viewed in Fig. l~ to remove the finished can 354 .. , 5 from its position overlying the positionlns pins 244 to clcar thccan completely from the cutter members and the pins. Additionally ; retraction of the slides 300 to the right also results in move-ment of the stripper ring 245 from the inner position illustrated by the upper stripper ring 245 in Figure l outwardly along the positioning pins 244 to the position illustrated by the lower , stripper ring 245 in Figure l. Movement of the stripper ring 245 , outwardly to the position substantialy adjacent the ends of pins .~ 244 results in the stripping of the scrap end 354" from the pins ~, 244 so that the scrap ends 354" are discharqed into the scrap lS removal means 416 etc. as shown in Figure l and similarly in ~ , Figure 17.
.. The retracting movement of the sleeve 266 also eventual ly result~ in movement of the~ore 350 beyond the end limit of elongated chamber 348 to ventthe bore 350 and consequently releas ~0 the trimmed can 354' from the vacuum chuck 280 as the can reaches a position in alignment with the discharge conveyor 360. The finished can has been discharged and the vacuum chuck 280 etc.
is in its completely retracted position illustrated by the lower vacuum chuck in Figure 4B as the elements reach position VI.
,; ¦ The chuck 280 etc. is consequently in position to receive the ¦ next can as it subseqnently moves into position I.
l The employment of the plural cutter units enablCS a ¦ high capacity operation of the preferred embodiment with down ¦ time due to cutter failure being kept to a minimum by virtUc o ~o ¦ thc casy replaccmcnt of the entirc cutter unit in a mattcr o} a :` . I , l . ¦ 2B
1~ . _ .~ .

~400~L~
few minutes as compared to the prior known devices in which a time consuming subs~antial disassembly of the components is required in the event of cutter unit failure. It is contemplated , that ten or more cutter units could be employed if desired.
Figure 15 illustrates modified knife members employing rela-tively small cutting elements enabling replacement of the cutting surfaces which can be replaced at minimum cost. Specifically, the difference between the cutter means of Figure 15 and the previous-ly discussed cutter means comprises the employment of an upper lo relatively thin cutter disc member 288 mounted between the radial flange 254 of retainer means on the end of shaft 202 and biassing means including slidable sleeve members 289 and 290 urged toward the end of the shat 202 by spring members 291. The radial flange 254 of the retain,er means extends radially outwardly of the outer end surface of shaft 202. The shafts 182 and 202 are identical to previously described shat members 182 and 202. The upper sleeve member 289 can be identical to the cutter member 200 of the cutter illustrated in ~igure 4A as previously discussed; however, the sleeve member 289 in the modification illustrated in Figure 15 merely serves to bias the cutting disc 288 rather than actually performing a cutting function.
The lower cutting disc 188' is fixedly positioned with respect to the flange surface 187 by means of threaded retainer 192 ànd intermediate member 289' by action of the threaded retainer means 192. Intermediate member 289' is identical to sleeve member 289. The discs 188' and 288 can be of different diameters so as to be interchangeable as required. ' ~,"~ 29 -1 " , ,, ~

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Figu~e 16 illustrates outer edge portions of cutter disc members 288 and 288' (which are structurally identical) employing di~ferent outer surface shapes all of which are effec-tive for achieving the cutting function. Disc portion A has 5 a conical outer edge surface A' concentric with respect to the axis of the disc and a shaft on which it is to be mounted.
: Disc portion ~ has a concave outer periphery B' and disc portion C has a cylindrical outer periphery C'. It should be noted . that each of the disc members provides two cutting edge corner portions defined by the intersection of the planar end surfaces of the disc members with the outer peripheral surfaces.
Figure 18 illustrates a second embodiment of the invention in which a central cutter knife 440 is employed in con-junction with a pair of diametrically.opposed planetary cutters 442 which cooperate with the central cutter knife 400 to trim .the ends of containers 354. In this embodiment, a base or pillar plate 20' essentially identical to pillar plate 20 provides sup-. port for a first vertical support pillar 26' and a second verti-cal support pillar 28'. A work piece positioning control cam flange 76' is supported on the pillar plate 28' for cooperation with aam followers 318' and 320' associated with a bracket 330' connected to first and second sleeve members 266' supported for reciprocation in a transverse bushing block i44 fixedly mounted on a main shaft 446. Main shaft 446 includes end shaft com-2 ponents supported between the members 26' and 28' by rotary bear-ing means with a central cage type portion including a plurality of connecting rods 448 drivingly joining the transverse bushing block 444 and a transverse cutter support block 449. Only one . ,~ 29a ._ ~! :

1 104~
of the connecting xods 448 is illustrated in Figure 16. Block 444 is connected by sleeve members 510, 512 and 514 to a second transverse block 451' connected to the shaft component supported l in bearings in member 26'.
5 ¦ Power for the embodiment of Figure 18 is provided from a main drive shaft 450 driven by an electric motor or other suitable power source in a counter-clock:;ise direction as viewed ~-_i . ~ ' .

:

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: from the left end of the main drive shaft 450. All subscquently : discussed directions of rotation will be as viewed from the left end of the main drive shaft 450~
Counter-clockwise rotation of drive shaft 450 is conveyed through a step-down transmission to a drive chain 452 drivingly connected to an idler sprocket assembly 454 supported for free rotation adjacent the end of shaft 446. A link 456 connects idler sprocket 454 to the end of a central cutter wheel drive shaft 458 supported for rotation coaxially within the members 446' 449, etc. to drivingly rotate the Xnife 440.
In operation, main drive sha~t 450 is driven in a counter-clockwise direction and subsequently drives knife 440 in a count,er-clockwise direction via elements 452, 454, 456 and 458. At the same time, shaft 450 drives shaft 446 in a clockwise direction via gears 462 and 464 and a chain 466. The last-men-,. tioned clockwise rotation is provided to element~s 444, 449 and 451. as well as vacuum chucks 280' carried by the members 444 and 449.
;, Permanent work piece cradles 470 extend from sleeve 266' over to . the area of the pIanetary cutters 442 and have stripper rims 472 at their outer extremities for removing tha waste rings 354"
from pins surrounding the planetary cutters (not shown) in a manner analagous to the operation of elements 244, 255 of the first embodiment. Additionally, the cage construction between the elements 444 and 449 includes a pair of finger discs 406' ¦25 supported by the connecting rods 448 etc. for rotation and opera-!~; tion in exactly the same manner as the finger discs 406 of the first embodiment.
Planetary cutters 442 are driven by gear members 474 .;
.

_. I ~ . .. , ;~

104(~0~1 keycd to the shaft on which the cutter members 442 are mounted and meshing with a sun gear 476 driven in a counter-clockwise _ direction from central cutter shaft 458. A cutter knife actuatiny cam 480 is fixed to the vertical support pillar plate 26' and serves the purpose of moving the planetary cutter members 442 radially inwardly and outwardly with respect to the sun cutter 440. This movement is effected by virtue of the fact that the shafts on which the planetary cutters 442 are mounted are capable of inward movement with respect to the central shaft 458 either by the employment of slide bearings in members 449, 451' or by . the supporting of the shafts on the end of a pivotal m~mber pro-vided at one end to means connected to elements 449 and 451 and carrying the shaft supporting cutters 442 at an opposite end in ; a manner of operation .~nalagous to the operation of the pivot bloc~ 204 of the ~irst embodiment. In any event, heavy springs ;~ 48q urge the cutter members 442 toward a cutting position over-lapping the central cutter 440.
. ¦ In operation, unfinished cans 354 are fed by an infeed conveyor 358 to be engaged by the finger discs 406' and deposited on the cradles 470 in approximately the twelve o'clock position of the cradle members. The vacuum chucks 280' are con-¦currently moving forwardly and vacuum is applied to the face ofthe chucks through passageways in member i44 and sleeves 266' to support the work piece for axial rotation caused by member 318' ¦
and the bevel gears 334, 336 etc. in a manner essentially identi to the operation of the chuck of the first embodiment. The open ¦can end is moved over the upper cutter 442 adjacent the central ¦
otter 440 since the cutters are in a spaced ~ondition. operatin . .

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of cam 480 then moves the upper cutter 442 downwardly in over-lapping cutting relation with respect to the cutter 440 so as to trim the scrap ring 364'' from the can end. As the cutter unit approaches the six o'clock position, the scrap ring has been trimmed from the can end and the vacuum chuck 280', sleeve 266' etc. is moving to the right to release the vacu,um in the chuck 280' and discharge the can and the scrap in the same manner as the first embodiment. In the meanwhile, the other container cradl~
470 is receiving a new can as the system continues to cycle.
While numerous modifications of the subject invention . will undoubtedly occur to those of skill in the art, it should be understood that the spirit and scope of the invention is to be limited solely by the appended claims.

~. ~ . I

Claims (23)

I CLAIM:

1. A can end trimmer apparatus for trimming the open cylindrical end of a cylindrical can having a closed opposite base end, said apparatus comprising:
a fixed main frame, main shaft means supported for rotation on said main frame, at least one self-contained removable cutter unit assembly including:
a cutter unit frame;
a first rotary knife having a circular cutting edge;
a second rotary knife having a circular cutting edge and positioned adjacent said first rotary knife;
selectively operable knife actuator means for moving said second rotary knife between a first, or cutting, knife position in which said circular cutting edges of said rotary knives overlap and a second, or non-cutting, knife position in which said cutting edges are spaced apart and do not overlap;
power transmission means drivingly connected to said first and second rotary knives for enabling rotation of said knives;
drive means for drivingly rotating said main shaft means;
attachment means enabling unitary mounting of said self-contained removable cutter unit assembly in an operative position on said main shaft;

a source of power drivingly engaged with said power transmission means when said cutter unit assembly is in said operative position for driving said rotary knife members;
can holder means mounted on said main shaft adjacent said cutter unit assembly for movement between a first holder position in which a can supported by its base end on said can holder has its open end spaced from said knife member and a second holder position in which the open end of a can on said holder encloses one of said knife members with a portion of the can wall extending between the rotary knife members when said second knife is in said second or non-cutting position;
cyclically operated knife control means engageable with said knife actuator means for causing said knife actuator means to position said second rotary knife in either said first or second knife positions during desired discrete portions of each revolution of said main shaft; and cyclically operated can holder positioning means operated in fixed timed relationship with said cyclically operated knife control means for moving said can holder to said second holder position at a time when said second knife is in said second knife position and retaining said holder in said second holder position while said second rotary knife first moves to said first knife position to effect cutting of an end portion of a can in the can holder from the remainder of the can and then moves back to said second knife position and for moving said can holder to said first holder position subsequent to said last-mentioned movement of said second rotary knife to said second knife position.

2. The invention of claim 1 wherein said work holder comprises a vacuum chuck; and further including:
a source of vacuum valving means normally connecting said source of vacuum to said vacuum chuck to enable the holding of a can in said vacuum chuck but disconnecting said source of vacuum from said vacuum chuck in response to positioning of said work holder in or closely near said first holder position.

3. The invention of claim 1 wherein said cutter unit assembly additionally includes:
a first cutter shaft mounted for rotation in fixed bearings on said cutter unit frame;
said first rotary cutter knife being mounted on said first cutter shaft;
a second cutter shaft oriented parallel to said first cutter shaft;
said second rotary cutter knife being mounted on said second cutter shaft; and wherein said knife actuator includes:
pivot block means mounted for pivotal movement on said cutter unit frame;
said second cutter shaft being mounted for rotation on said pivot block means; and a movable drive member having one portion engag-ing said pivot block means and a second portion engaging said cyclically operated knife control means when said cutter unit assembly is in said operative position.

4. The invention of claim 3 additionally including:
unfinished can infeed means having a discharge end adjacent the path of movement of said can holder means during rotation of said main shaft:
can outfeed means having a finished can receiving portion positioned adjacent the path of movement of said can holder means for receiving cans released from said vacuum chuck in response to the disconnection of said source of vacuum to said vacuum chuck;
wherein said work piece holder additionally includes an arcuately curved can cradle means of generally cylindrical curvature positioned radially inwardly of said vacuum chuck with respect to the axis of said main shaft and extending forwardly from said vacuum chuck toward said rotary cutter knives;and finger disc means mounted on said main shaft adjacent said can cradle means for engaging a can on said can infeed means and depositing said can on said can cradle means prior to oper-ation of said valving means for connecting the source of vacuum to said vacuum chuck.

5. The invention of claim 4 wherein said finger disc means comprise a plurality of radially extending flange members having an arcuate outer surface with a center of curvature eccentric with respect to the axis of said main shaft and addi-tionally having a leading work piece engaging chordal surface with respect to the arcuate outer surface.

6. The invention of claim 5 wherein said self-contained cutter unit assembly additionally includes a plurality of parallel work piece positioning pin members supported on one end by said cutter unit frame and extending parallel to said second cutter shaft about the periphery of said second cutter shaft and having outer end terminations in general alignment with the circular cutting edge of said second rotary knife, said positioning pin members being positioned and dimensioned to be received in the end of a can as a can is moved by said vacuum chuck into position to be cut by said rotary cutter knives so that said positioning pins support and retain the scrap ring end following the cutting of the scrap ring end from the can.

7. The invention of claim 6 additionally including:
stripper ring means mounted for reciprocation on said positioning pins for movement between a first ring position adjacent the supported ends of said positioning pins and a second ring position generally adjacent the outer end termination of said positioning pins.

8. The invention of claim 7 additionally including cyclically operated stripper ring actuator means for moving said stripper ring from said first ring position to said second ring position in timed conjunction with movement of said can holder to said first holder position and for moving said stripper ring to said first ring position in response to movement of said can holder to said second holder position so that said stripper ring moves a scrap ring on said positioning pins following a cutt-ing operation from supporting engagement with said positioning pin to discharge said scrap ring from the end portions of said positioning pins into a scrap receiving means.

9. The invention of claim 8 wherein said cyclically operated can holder positioning means includes:

slide sleeve means mounted for axial reciprocation parallel to the axis of said main shaft;
a slide plate connected to said slide sleeve and mounted for movement in slide bearings on said main shaft;
cam follower means mounted on an opposite end of said slide sleeve means;
a workpiece control cam having a radial cam flange fixedly mounted on said main frame and engaged by said cam follower means for providing timed reciprocation of said cam follower means and said slide sleeve;
said vacuum chuck being mounted axially with respect to said slide sleeve on the end of said slide sleeve opposite said cam follower means;
said can cradle being mounted on said slide plate adjacent said vacuum chuck so that said can cradle and said vacuum chuck are reciprocated unitarily by said slide sleeve; and wherein said cyclically operated stripper ring actuator means comprises linkage means connected between said slide plate and said stripper ring.

10. The invention of claim 9 wherein said cam follower means comprises a first cam follower roller engageable with one side of said radial cam flange and a second cam roller engageable with an opposite side of said radial cam flange so that cam follower rollers roll along opposite surfaces of said cam;
rotary drive means for said vacuum chuck comprising:
workpiece driveshaft means extending axially through said slide sleeve with said vacuum chuck being mounted on one end of said workpiece driveshaft means; gear means mounted on an opposite end of said workpiece driveshaft;
cam follower driven gear means fixedly connected to said first cam follower and meshing with said gear means on the end of said workpiece drive-shaft whereby rotation of said first cam follower provides rotational drive for said workpiece driveshaft and said vacuum chuck as said first cam follower is traversed about the periphery of said control cam.

11. The invention of claim 10 wherein said cyclically operated knife control means includes:
a radial cam follower support flange radially position-ed for rotation on said main shaft adjacent said cutter unit assembly;
a fixed cutter control cam mounted on said main frame adjacent said cam follower support flange;
a cam follower roller;
a cam follower support arm supporting said cam follower roller on one end;
a pivot shaft supported for pivotal movement about its axis on said cam follower support flange;
said cam follower support arm being affixed to one end of said pivot shafts;
a cutter actuator arm fixedly connected to an opposite end of said pivot shaft;
a portion of said cutter actuator arm radially posi-tioned with respect to the axis of said pivot shaft being in engagement with said second portion of second moveable drive member of said knife actuator so that said cutter control cam oscillates said cutter actuator arm to actuate said knife actuator at preselected discrete portions of each revolution of said main shaft.

12. The invention of claim 11 additionally including a main rotary sleeve mounted for rotation axially with respect to said main shaft on said fixed main frame;
said source of power drivingly engaged with said power transmission means when said cutter unit assembly is in said operative position including a ring gear coaxially fixed to said main sleeve and meshing with an input gear of said power trans-mission means of said cutter unit.

13. A can end trimmer apparatus for trimming the open cylindrical end of a cylindrical can having a closed opposite base end, said apparatus comprising a fixed main frane, main shaft means supported for rotation on said fixed main frame, means including a central rotary cutter knife positioned coaxially of said main shaft means, first and second rotary planetary knife members each having a circular cutting edge positioned adjacent said central rotary knife, support means carrying said first and second rotary planetary knife members for orbital movement about said central rotary knife, selectively operable knife actuator means for moving said first and second rotary planetary knife members between a first or cutting knife position in which said circular cutting edges of said rotary planetary knives overlap the cutting edge of the central rotary cutter knife and a second or non-cutting knife position in which said cutting edges are spaced apart and do not overlap, power transmission means driving-ly connected to said first and second rotary planetary knives for enabling axial rotating of said planetary knives, drive means for drivingly rotating said main shaft means, a source of power drivingly engaged with said power transmission means when said cutter unit assembly is in said operative position for driving said rotary planetary knife members, can holder means mounted on said main shaft facingly adjacent said cutter means for movement between a first holder position in which a can supported by its base end on said can holder has its open end spaced from said knife members and a second holder position in which the open end of a can on said holder encloses one of said planetary knife members with a portion of the can wall extending between said rotary planetary knife member when said planetary knife is in said second or non-cutting position, cyclically operated knife control means engageable with said knife actuator means for causing said knife actuator to position said second planetary knives in either said first or second knife positions during desired discrete portions of each revolution of said main shaft and cyclically operated can holder positioning means operated in fixed timed relationship with said cyclically operated knife control means for moving said can holder to said second holder position at a time a planetary knife aligned with said holder is in said second or non-cutting knife position and retaining said holder in said sec-ond holder position while said aligned planetary knife first moves to said first or cutting knife position to effect cutting of an end portion of any can in the can holder from the remainder of the can and then moves back to said second or non-cutting knife position and for moving said can holder to said first holder position subsequent to said last-mentioned movement of said aligned planetary knife to said second or non-cutting position.

14. The invention of claim 13 wherein said work holder comprises a vacuum chuck, and further including a source of vacuum, valving means normally connecting said source of vacuum to said vacuum chuck to enable the holding of a can in said chuck but disconnecting said source of vacuum from said vacuum chuck in response to positioning of said work holder in or closely near said first holder position.

15. Automatic apparatus for trimming the open cylin-drical ends of cylindrical cans having a closed opposite base end, said apparatus comprising:
a fixed main frame, main shaft means supported for rotation on said main frame, a pair of self-contained cutter unit assemblies, each cutter unit assembly including:
a cutter unit frame;
a first rotary knife having a circular cutting edge defined at the periphery of a radial end of said knife;
a second rotary knife having a circular cutting edge defined at the periphery of a radial end of said knife;
selectively operable knife actuator means for moving said second rotary knife between a first, or cutting, knife position in which said circular cutting edges of said rotary knives overlap and -a second, or non-cutting, knife position in which said cutting edges are spaced apart and do not overlap;
power transmission means drivingly connected to said first and second rotary knives for enabling rotation of said knives;
drive means for drivingly rotating said main shaft means;
attachment means enabling unitary mounting offside self-contained cutter unit assemblies in operative positions on dia-metrically opposite sides of a central portion of said main shaft;

a source of power drivingly engaged with said power transmission means when said cutter unit assemblies are in said operative positions for driving said rotary knife members;
can holder means mounted on opposite sides of said main shaft adjacent an associated cutter unit assembly for move-ment between a first holder position in which a can supported by its base end on said can holder has its open end spaced from the knife members of the associated cutter unit assembly and a second holder position in which the open end of a can on said holder encloses one of said last-mentioned knife members with a portion of the can wall extending between the last-mentioned rotary knife members when the second knife of the associated cutter unit assembly is in said second, or non-cutting, position;
cyclically operated knife control means engageable with said knife actuator means for causing said knife actuator means to position the second rotary knife of each cutter unit assembly in either said first or second knife positions during desired discrete portions of each revolution of said main shaft;
and cyclically operated can holder positioning means operated in fixed timed relationship with said cyclically operated knife control means for moving said can holder to said second holder position at a time when said second knife of the associated cutter unit assembly is in said second knife position and retain-ing said holder in said second holder position while said last-mentioned second rotary knife first moves to said first knife position to effect cutting of an end portion of a can in the can holder from the remainder of the can and then moves back to said second knife position and for moving said can holder to said first holder position subsequent to said last-mentioned movement of said second rotary knife of the associated cutter unit assembly to said second knife position.

16. The invention of claim 15 wherein each of said work holders includes a vacuum chuck; and further including:
a source of vacuum;
valving means normally connecting said source of vacuum to said vacuum chucks to enable the holding of a can in said vacuum chuck but disconnecting said source of vacuum from said vacuum chuck in response to positioning of said work holder in or closely near said first holder position.

17. The invention of claim 16 wherein each of said cutter unit assemblies additionally includes:
a first cutter shaft mounted for rotation in fixed bearings on said cutter unit frame and including a radial position-ing flange;
said first rotary cutter knife being mounted on said first cutter shaft in abutting relation to said positioning flange a second cutter shaft oriented parallel to said first cutter shaft and having a radial end surface in a common plane with said radial positioning flange;
said second rotary cutter knife being mounted on said second cutter shaft and having one end surface aligned with said radial end surface; and wherein said knife actuator means includes pivot block means mounted for pivotal move-ment on said cutter unit frame;
said second cutter shaft being mounted for rotation on said pivot block means; and a movable drive member having one portion engaging, said pivot block means and a second portion engaging said cyclically operated knife control means when said cutter unit assembly is in said operative position.

18. The invention of claim 15 wherein at least one of said rotary knife members comprises a relatively thin cutter disc having a peripheral cutting edge and an axial aperture received over a cantilever cutter shaft portion having an outer end surface extending radially with respect to its axis, removable flange means mounted on said canti-lever cutter shaft portion defining a radial abutment flange sur-face extending radially outwardly adjacent and essentially co-planar with the outer end surface of the cutter shaft portion, a slide sleeve including a radial surface facing said abutment flange surface mounted on said shaft for axial reciprocation with respect thereto, said relatively thin cutter disc being positioned between the radial surface of the slide sleeve and the abutment flange surface; and biassing means for urging said slide sleeve toward said removable flange means so that said relatively thin cutter disc is positively and accurately positioned against said abutment flange to provide an accurate positioning of said cutting edge.

19. The invention of claim 18 wherein the outer peri-phory of said cutter disc is a cylindrical surface coaxial with the axis of said cutter shaft portion.

20. The invention of claim 18 wherein the outer periphery of said cutter disc is a conical surface coaxial with the axis of said cutter shaft portion.

21. The invention of claim 18 wherein the outer periphery of said cutter disc is a concave surface.

22. The invention of claim 15 wherein each of said rotary knife members comprises a relatively thin cutter disc having planar sides the outer periphery of which sides define peripheral cutting edges, each of said discs being received over a different one of two parallel cantilever cutter shaft portions having parallel outer end surfaces extending radially with respect to the axis of said shaft portions, a removable flange means mounted on said canti-lever cutter shaft portions defining a radial abutment flange surface extending radially outwardly adjacent the outer end surface of the cutter shaft portions, a slide sleeve including a radial surface facing said abutment flange surface mounted on each shaft for axial reciprocation with respect thereto, said relatively thin cutter discs being positioned between the radial surfaces of the slide sleeve and the abutment flange surface;
and biassing means for urging said slide sleeves toward said removable flange means so that said relatively thin cutter disc is positively and accurately positioned against an abutment flange to provide an accurate positioning of said cutting edges.

23. A can end trimmer apparatus for trimming the open cylindrical end of a cylindrical can having a closed opposite base end, said apparatus comprising:
a fixed main frame, main shaft means supported for rotation on said main frame, a cutter unit assembly including:
a first rotary knife having a circular cutting edge;
a second rotary knife having a circular cutting edge and positioned adjacent said first rotary knife;
selectively operable knife actuator means for moving said second rotary knife between a first, or cutting, knife position in which said circular cutting edges of said rotary knives overlap and a second, or non-cutting, knife position in which said cutting edges are spaced apart and do not overlap;
power transmission means drivingly connected to said first and second rotary knives for enabling rotation of said knives;
drive means for drivingly rotating said main shaft means;
a source of power drivingly engaged with said power transmission means when said cutter unit assembly is in operative position for driving said rotary knife members;
can holder means mounted on said main shaft adjacent said cutter unit assembly for movement between a first holder position in which a can supported by its base end on said can holder has its open end spaced from said knife members and a second holder position in which the open end of a can on said holder encloses one of said knife members with a portion of the can wall extending between the rotary knife members when said second knife is in said second or non-cutting position;

cyclically operated knife control means engageable with said knife actuator means for causing said knife actuator means to position said second rotary knife in either said first or second knife positions during desired discrete portions of each revolution of said main shaft; and cyclically operated can holder positioning means operated in fixed timed relationship with said cyclically operated knife control means for moving said can holder to said second holder position at a time when said second knife is in said second knife position and retaining said holder in said second holder position.
while said second rotary knife first moves to said first knife position to effect cutting of an end portion of a can in the can holder from the remainder of the can and then moves back to said second knife position and for moving said can holder to said first holder position subsequent to said last-mentioned movement of said second rotary knife to said second knife position.