Can trimming apparatus

Claim 2

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 selfcontained 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.

Claim 3

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.

Claim 4

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 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.

Claim 5

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 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 operation of said valving means for connecting the source of vacuum to said vacuum chuck.

Claim 6

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 additionally having a leading work piece engaging chordal surface with respect to the arcuate outer surface.

Claim 7

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 end terminations in general alignment with the circular 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.

Claim 8

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.

Claim 9

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 on said positioning pins followIng a cutting operation from supporting engagement with said positioning pins to discharge said scrap ring from the end portions of said positioning pins into a scrap receiving means.

Claim 10

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 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.

Claim 11

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 driveshaft 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.

Claim 12

The invention of claim 10 wherein said cyclically operated knife control means includes: a radial cam follower support flange radially positioned 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 shaft; a cutter actuator arm fixedly connected to an opposite end of said pivot shaft; a portion of said cutter actuator arm radially positioned 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 said revolution of said main shaft.

Claim 13

The invention of claim 11 additionally including a main rotary sleeve mounted for rotation 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 transmission means of said cutter unit.

Claim 14

Automatic apparatus for trimming the open cylindrical 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 beween 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 selfcontained cutter unit assemblies in operative positions on diametrically 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 an mounted on opposite sides of said main shaft adjacent on associated 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 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 retaining 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.

Claim 15

Automatic apparatus for trimming the open cylindrical 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 beween 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 selfcontained cutter unit assemblies in operative positions on diametrically 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 an mounted on opposite sides of said main shaft adjacent on associated 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 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 retaining 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.

Claim 16

The invention of claim 13 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.

Claim 17

The invention of claim 14 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 positioning 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 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 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.

Claim 18

The invention of claim 13 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 cantilever cutter shaft portion defining a radial abutment flange surface extending radially outwardly adjacent and essentially coplanar 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.

Claim 19

The invention of claim 16 wherein the outer periphery of said cutter disc is a cylindrical surface coaxial with the axis of said cutter shaft portion.

Claim 20

The invention of claim 16 wherein the outer periphery of said cutter disc is a conical surface coaxial with the axis of said cutter shaft portion.

Claim 21

The invention of claim 16 wherein the outer periphery of said cutter disc is a concave surface.

Claim 22

The invention of claim 13 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 cantilever 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.