HK1021359B - Dual can rotating transfer plate to conveyor belt - Google Patents

Description

Double-can rotating plate conveyor facing a conveyor belt

Background

The present invention relates to a continuous motion apparatus for coating cylindrical containers, and more particularly to an apparatus for transferring coated containers to a curing oven without the use of a coating chain.

In high speed continuous motion equipment for coating cylindrical containers (cans) such as beverages, the containers which are coated to have wet coating are off-loaded from a support bar in a so-called coating chain which transports the containers through an ink curing and drying oven. Such a coating apparatus is disclosed in U.S. patent No.5,183,145 to R Williams et al entitled "apparatus and method for automatically positioning a positioning valve mechanism for controlling the application of compressed air to a rotary conveyor spindle" and U.S. patent No.4,445,431 to J Stirbis entitled "disk conveyor system" issued on 5.1.1984. U.S. Pat. Nos. 5,183,145 and 4,445,431, and patents cited therein as prior art, are hereby incorporated by reference.

Over the years, the production speed of continuously running can applicators has increased, currently exceeding 1800 cans per minute, and problems with the unloading of cans with wet finish onto the finish chain bar and with the finish chain itself have become increasingly apparent and have caused problems. These problems include excessive noise and damage to the can due to contact between the metal can and the metal rod. Not only are long finishing chains expensive, but because the chains are made of many pieces, the chains tend to wear and break at high speeds.

Because of the above problems, it is possible that the coated containers, particularly iron containers, are not conveyed through the curing oven on the coating chain bar as they are, as opposed to being conveyed by belts. Such an apparatus using a belt is disclosed in U.S. patent No.4,771,879 issued on 20/9/1988 and pertaining to a container transfer system of the type f.l.. Shriver. U.S. patent No.4,771,879, and patents cited therein as prior art, are also incorporated herein by reference.

In U.S. patent No.4,771,879, cans are dressed on axially forwardly extending mandrels mounted on the periphery of a mandrel wheel. The decorated cans are transferred from the mandrels to a wheel-like first conveyor, then to the edge of a wheel-like second conveyor, and then to a conveyor belt for transporting the containers with wet decoration through a curing oven. The cans conveyed by the second conveyor extend radially relative to the axis of rotation of the second conveyor. The second conveyor of us patent No.4,771,879 is expensive in construction, although no painting chain is used, and is made of many components and must be closely coordinated between the operation of the first and second conveyors. Furthermore, the axes of rotation of the two conveyors are arranged transversely to one another, making the use of space uneconomical.

Summary of The Invention

According to the invention, cans with wet coating are transferred from a mandrel wheel to a first transfer wheel, then to a second transfer wheel and then to a conveyor belt, as described in U.S. patent No.4,771,879. The most obvious difference between us patent No.4,771,879 and the present invention is that in the present invention the axes of rotation of the conveyors are parallel to each other, and the second conveyor of the present invention has a simplified construction because the cans conveyed by it project axially with respect to the axis of rotation of the second conveyor. More specifically, the second conveyor has a rotating plate body and a stationary suction duct, the open side of which is covered by a holed portion of the plate body during rotation.

The cans are moved in a single row when the first conveyor takes the cans, and the cans are arranged in two rows when the first conveyor rotates, and are transferred from the two rows to the rotating plate. The open ends of the cans are in contact with perforated areas of the major planar surface of the plate body, with the openings in the perforated areas being disposed through the plate body in two circular arrays about an axis centered on the axis of the plate body. Suction within the duct extends through the plate holes to draw the cans rearwardly toward the swivel plate as the cans pass through the duct. The closed end of the can is engaged with the vertical section of the running foraminous conveyor belt to be held thereon by suction extending through the conveyor belt as the effect of the duct suction on the can is reduced. The conveyor belt carries the cans through the curing oven or transports the cans to another conveyor that extends through the curing oven.

It is therefore a principal object of the present invention to provide a means for transporting cans from a continuous high speed running coater through a curing oven without the cans being mounted on the struts of the coating chain.

It is a further object to provide an apparatus of the above kind wherein the first and second conveyors which rotate about laterally offset parallel axes are in partial overlap, wherein the second conveyor includes a rotatable plate body with a planar surface for receiving cans from the first conveyor, the open ends of the cans being directly engaged with the planar surface perpendicular to the axis of rotation of the second conveyor.

It is a further object to provide an apparatus of the above kind wherein cans are transferred directly from the planar surface to the vertical run of the conveyor.

It is a further object to provide such a device which operates on the principle that both suction and magnetic forces can be used to hold the iron container.

It is a further object to provide such an apparatus wherein the linear velocity of the containers on the second conveyor can be lower than the linear velocity of the containers on the first conveyor.

These and other objects of the present invention will become more apparent to those skilled in the art from the following description of the drawings, in which:

brief description of the drawings

Fig. 1 is a side view of a continuously operating can decorating apparatus of the present invention.

Fig. 2 is a partial side schematic view of the main canister transfer member.

Fig. 3 is a front view of the drive mechanism and vacuum system of the plate conveyor.

Fig. 4 is a partial expanded view taken along line 4-4 and in the direction of arrows 4-4 in fig. 3.

FIG. 5 is a cross-sectional view of the belt tensioner taken along line 5-5 of FIG. 3 and in the direction of arrows 5-5.

Fig. 6 is a front view of a plate conveyor.

Fig. 6A is a cross-sectional view taken along line 6A-6A of fig. 6 and in the direction of arrows 6A-6A.

Fig. 6B is another cross-sectional view taken along line 6A-6A and in the direction of arrows 6A-6A in fig. 6, showing a modified construction of the plate conveyor.

Figure 7 is a simplified plan view of the apparatus shown in the other figures for ease of understanding of its structure and operation. Detailed description of the drawings

To simplify the following description, the above-mentioned U.S. Pat. No.5,183,145 is compared with other known techniques.

Referring now to the drawings and in particular to fig. 1, fig. 1 shows a continuous run cylindrical can decorating apparatus incorporating the present invention. The right hand input of the device shown in fig. 1 is the same as the input of the device shown in fig. 1 in U.S. patent No.5,183,145. The output end of the apparatus of the present invention replaces the coating chain with struts at the output end of the apparatus shown in figure 1 of U.S. patent No.5,183,145 with a suction plate conveyor 102 and a conveyor belt 105.

Briefly, the apparatus shown in FIG. 1 herein has an infeed conveyor slot 15 for receiving an uncoated can 16, open at one end 16b (FIG. 7), from a can supply (not shown) and loading it into an arcuate seat or pocket 17 located on the periphery of axially aligned spaced rings 14 secured to a wheel-shaped spindle conveyor 18 keyed to a horizontal drive shaft 19. Each horizontal shaft 20 forms part of a single spindle/actuator assembly 40 (fig. 2) which is also mounted on the wheel 18 such that each spindle 20 is generally horizontally aligned with a single support 17 at a short distance downstream from the infeed conveyor 15. In this short region the uncoated cans 16 are moved horizontally, from the supports 17 to the spindles 20. The suction applied through the axial passage extending to the outer or forward end of the mandrel 20 will seat the can 16 back toward the position where the closed end 16c of the can 16 is eventually seated on the mandrel 20. The cans 16 should be loaded onto the mandrels 20 when the mandrels 20 are adjacent to the sensors 33, which detect whether each mandrel 20 carries a loaded can 16. In a manner known in the art, if the sensor 33 detects that the mandrel 20 is missing or not properly loaded, the missing or mis-loaded mandrel 20 will be transferred to a "non-printing" position in which it will not engage the blanket 21 as the particular mandrel 20 passes through the finish area of the can 16 on the mandrel 20 where the printing blanket 21 would normally engage.

When mounted on the mandrel 20, the cylindrical side wall 16a of the can 16 is finished by engaging a continuously rotating image-carrying felt 21 in an impression finishing zone 22 for multicolor printing. Thereafter, the finished can 16, still mounted on the mandrel 20, is coated with a protective film, typically paint, by engaging the periphery of the roller 23 in the painting station 24. The can 16 with the finish and protective film is then transferred from the mandrel 20 onto a holding or suction means consisting of a suction cup 36. In this transfer, the suction means 36 operate in a single row along the periphery of the transfer wheel 27 in a first transfer zone 99 (fig. 2), which first transfer zone 99 is located between the painting means 24 and the feed of the cans 16 into the recesses 17. The transfer wheel 27 rotates about the horizontal axis 28 as a center to place the cans 16 transferred by the wheel 27 at the second transfer zone 98 on the forward facing plane 101 of the endless suction plate conveyor 102. This conveyor 102 carries cans 16 downstream from the transfer zone 98 through a holding zone that extends to the can filling zone 95 where the closed ends 16c of the cans 16 abut against a vertical run 103 of a perforated closed loop conveyor 105 that moves upwardly. Cans 16 on the conveyor plate 102 are drawn forwardly into engagement with the vertical run 103 of the conveyor belt by suction generated in a known manner to pass through the conveyor belt 105 and act on the desired location behind the run 103. The vertical traveling section 103 is guided at its downstream or upper end by a suction type idler roller 189 and is connected to the horizontal traveling section 104. The conveyor 105 may convey the cans 16 through a curing oven (not shown) or to one or more additional conveyors (not shown) that convey the cans 16 through the curing oven.

As described in U.S. patent No.5,183,145, the holding devices 36 are arranged in a single row in the transfer zone 99 and are rearranged in double rows 36a, 36b on the transfer wheel 27 as it passes through the transfer zone 98. U.S. patent No.5,183,145 also discloses that the spacing between adjacent suction means 36 in the transfer zone 99 is substantially less than the spacing between adjacent spindles 20, which travel at a substantially higher linear speed than the suction means 36. In addition, U.S. Pat. No.5,183,145 also discloses how the relatively fixed valve member on the V-shaped casting 65 can be automatically adjusted in position to maintain operational coordination between the spindle conveyor 18 and the transfer wheel 27 as the linear speed differential between the spindle 20 and the suction mechanism 36 varies.

The circular opening 107 in the middle of the annular plate conveyor 102 is closed with a circular lid 108 (fig. 4) and bolts 109 are passed through clearance openings 111 (fig. 6) along the periphery of the lid 108 to secure the annular plate conveyor 102 to the lid 108. The cap 108 is keyed to a stub shaft 110, the stub shaft 110 being rotatably supported in axially spaced bearings 112, 113 mounted on opposite legs of a U-shaped bracket 114, the bracket 114 being secured to a mounting plate 115 by a plurality of bolts 116. A driven sprocket 117 mounted between the arms of the bracket 114 is mounted and keyed to the shaft 110. Double-sided timing belt 120 meshes with the teeth of driven sprocket 117, idler sprockets 118, 119 and drive sprocket 121. A drive sprocket 121 is keyed to the drive shaft 28 of the conveyor. Idler sprocket 118 is rotatably mounted on one end of arm 122, the other end of arm 122 being sandwiched between the short legs of a U-shaped adjustment member 225, the web portion of the adjustment member being interposed between arm 122 and mounting plate 115. The fastening bolts 124, 124 pass through the longitudinal slots 123, 123 in the arm 122 and the clearance openings in the web portion of the adjustment member 225 to engage the threaded holes in the mounting plate 115 to retain the arm 122 in its set position.

Bolts 126 secure the mounting plate 115 to the mounting frame of the finisher and fasteners 127 extend forwardly from the mounting plate 115. The circular ventilation structure 125 is fixed to the front end of the holder 127 by a plurality of bolts 128. The venting structure 125 has concentric circular side walls 131, 132 connected by a rear wall 133, thereby forming a circular recess. The free leading edges of the side walls 131, 132 are held apart by a plurality of rods 134 and baffles 136, 137, the baffles 136, 137 being located at the upstream and downstream ends respectively of a suction air duct 135 formed therebetween, the suction air duct constituting the lower half of the recess formed by the ventilation structure 125. A short sleeve 138 is located at the 6 o' clock position to secure a hose (not shown) from a vacuum source (not shown) to the air chute 135. Extending across the front of the vent structure 125 and downstream of the partition 137 is a control 140 having a pair of elongated openings 141, 142 that are angled downwardly in the downstream direction for reasons that will be explained.

The rotating plate conveyor 102 is located in front of the ventilation structure 125, closely spaced therefrom and serves as a cover for the air chute 135. A suitable spacing between the rear surface 159 of the plate conveyor 102 and the free front ends of the duct walls 131, 132 is 0.02 ".

As shown in fig. 6, the plate conveyor 102 has one set of openings 141 arranged in a single row to form an outer circular array and another set of openings 142 arranged in a single row to form an inner circular array. The inner and outer circular arrays of openings 141, 142 are concentric about the axis of rotation 110, which is the center of the plate conveyor 102. The forward facing surface of the plate conveyor 102 has shallow concentric grooves 151, 152. The outer array of openings 141 extend rearwardly from the base 161 of the outer groove 151 and the inner array of openings 142 extend rearwardly from the base 162 of the inner groove 152.

In a suitable construction for processing 2.6 inch diameter aluminum cans, each slot base 161, 162 has a width of 3/4 "and each opening 141, 142 has a diameter of 7/32" with a spacing of about 1.3 between adjacent openings in each row. With this arrangement, each can 16 is held on the plate conveyor 102 by suction which draws air into the air chute 135 through the two openings 141 when the can 16 is in the outer array and through the two openings 142 when the can 16 is in the inner array.

The plate conveyor 202 shown in fig. 6B retains the features of the plate conveyor 102 of fig. 6A with the modification of adding rear surface shallow circular grooves 181, 182 that are aligned with the corresponding front surface shallow grooves 151, 152. Although not illustrated, the recesses 181, 182 may have different depths and/or widths than the respective shallow recesses 151, 152. Thus, if the front surface of plate conveyor 202 having grooves 151, 152 is damaged, plate conveyor 202 mounted on cover 108 of FIG. 6B may be inverted to provide a new and/or undamaged forward facing surface for engaging the open end 16B of cans 16 conveyed by holding members 36a, 36B.

The slots 151, 152 provided on the slat conveyor 102 serve to prevent excessive suction from being created to collapse the cans 16, which may occur if the entire free end of the can side wall is brought into close contact with the forward facing surface of the slat conveyor 102.

Thus, it can be seen that the present invention provides a continuous rotating suction plate conveyor incorporating a suction conveyor belt to replace the conventional furnace belt bar conveyor chain. As described above, the present invention uses suction to hold the cans on the plate conveyor and the conveyor belt.

When using a paint chain, the grippers 36a, 36b must track the pins of the chain in order to reliably transfer the cans 16 from the grippers 36a, 36 b. The configuration of the present invention is also advanced in the area of discharge of the cans 16 from the holders 36a, 36b so that the linear velocity of the cans 16 on the flat conveyor 102 may be lower than the velocity of the cans 16 when the cans 16 are discharged from the holders 36a, 36 b. For transferring cans of ferrous or non-ferrous (e.g. aluminium) holding methods may be used. However, rather than using suction to paint cans, magnetic forces are used to hold cans on a flat conveyor and/or conveyor belt.

The invention has been described with respect to specific embodiments thereof, but many other variations and modifications will be apparent to those skilled in the art. Accordingly, the invention is not to be limited by the specific disclosure herein, but only by the appended claims.

Claims (20)

1. An apparatus for transporting containers, each container having an open end and a closed end opposite the open end, the apparatus comprising:

first and second continuously operating conveyors rotatable about laterally spaced respective first and second axes generally parallel to one another;

a continuously running mandrel conveyor rotatable about a third axis and a continuously running conveyor belt comprising a first running section;

said first conveyor being located axially forward of said second conveyor and said conveyor, said first run passing forward of said second conveyor;

a plurality of container-transferring mandrels on said conveyor extending forwardly therefrom;

a plurality of container transfer suction members projecting rearwardly of said first conveyor and in an array about said first axis;

said second conveyor having a forwardly facing generally planar surface for receiving containers, the surface being generally perpendicular to said second axis and from which first suction draws containers rearwardly from said first conveyor onto said first conveyor, thereby causing containers to engage and be held on said planar surface as portions of said planar surface pass by a holding zone;

said conveyor and portions of said first conveyor being in facing relationship to each other on a first transfer zone where said suction members pick up containers transferred by said mandrels;

portions of said first and second conveyors being in facing relationship with each other on a second conveying area where said substantially planar surfaces receive containers projecting rearwardly from said suction members;

said first run and portions of said second conveyor being in facing relationship to each other at a filling area where said first run of said conveyor belt picks up forwardly projecting containers from a second conveyor area, holding the picked containers on said first run by another suction force;

the filling zone being downstream of the second transfer zone, the holding zone extending between the second transfer zone and the filling zone;

said closed end being in front of said open end when said containers are on said first and second transfer zones and on said filling zone;

the open end is operatively engaged with the generally planar surface at the second transfer zone, the closed end is operatively engaged with the suction member at the first transfer zone, and the closed end is operatively engaged with the first run at the can filling zone.

2. The apparatus for transporting containers of claim 1, wherein: the conveyor belt also has a second run downstream of the first run and moving forward away from the second conveyor.

3. The apparatus for transporting containers of claim 2, wherein: the first run moves upwards while passing through the can filling zone.

4. The apparatus for transporting containers of claim 3 wherein: holding the containers on said conveyor belt by said further suction while moving from said filling area to said second run by said conveyor belt; the further suction is generated by suction.

5. The apparatus for transporting containers of claim 4 wherein: the containers are oriented with their respective longitudinal axes substantially parallel to said first and second axes as they move from said filling zone to said second run.

6. The apparatus for transporting containers of claim 1, wherein: the suction is generated by suction.

7. The apparatus for transporting containers of claim 1, wherein: said second conveyor having a stationary low pressure duct with an open side facing forwardly and a plate-like member with a first surface constituting said generally planar surface;

said panel-shaped member being continuously rotatable about said second axis and operatively located in front of said member to cover said open side;

the panel-shaped member has a plurality of apertures extending therethrough and positioned to communicate with the duct upon rotation of the panel-shaped member, such that the suction is created by the low pressure within the duct.

8. The apparatus for transporting containers of claim 7 wherein: at least some of the apertures are arranged in a circular array centred on the second axis.

9. The apparatus for transporting containers of claim 7 wherein: a second conveyor having a shallow trough extending rearwardly from said planar surface and about said second axis, said shallow trough being defined by spaced first and second lateral side walls, at least some of said openings communicating with said shallow trough;

each of said containers having a transverse cross-sectional dimension substantially greater than the spacing between said lateral side walls;

the first and second conveyors are operably positioned such that containers accessed by the second conveyor extend across the two lateral side walls.

10. The apparatus for transporting containers of claim 9 wherein: the shallow groove is further defined by a rear sidewall;

the at least some apertures extend rearwardly from the rear edge wall.

11. The apparatus for transporting containers of claim 10 wherein: the at least some of the apertures are disposed in a circular array centered on the second axis.

12. The apparatus for transporting containers of claim 11 wherein: the transverse cross-sectional dimension is substantially greater than a spacing between adjacent apertures in the circular array.

13. The apparatus for transporting containers of claim 12 wherein: the transverse cross-sectional dimension is at least substantially equal to twice a pitch between adjacent apertures in the circular array.

14. The apparatus for transporting containers of claim 7 wherein: said apertures being arranged in concentric first and second circular arrays centered on said second axis, said second array being interposed between said second axis and said first array;

on the second transfer zone, the suction members are arranged so as to form an arrangement of a first and a second column of suction members, the second column being interposed between the first axis and the first column;

the first and second conveyors are operably positioned to convey containers on the holding members in the first row to the second row on the planar surface and to convey containers on the holding members in the second row to the first row on the planar surface.

15. The apparatus for transporting containers of claim 14 wherein: a second conveyor having first and second shallow grooves extending rearwardly from said planar surface and about said second axis, each of said shallow grooves being defined by a pair of spaced lateral side walls, said openings of said first circular array communicating with said first shallow grooves and said openings of said second circular array communicating with said second shallow grooves;

the containers each have a transverse cross-sectional dimension substantially greater than the spacing between the lateral side walls defining the shallow channels, such that containers conveyed onto the planar surface in the first row extend across the two lateral side walls defining the first shallow channel and containers conveyed onto the planar surface in the second row extend across the two lateral side walls defining the second shallow channel.

16. The apparatus for transporting containers of claim 15 wherein: each shallow groove is further defined by a single rear sidewall;

the opening extends rearwardly from the rear edge wall.

17. The apparatus for transporting containers of claim 16 wherein: the transverse cross-sectional dimension is substantially greater than a spacing between adjacent apertures in each of the first and second circular arrays.

18. The apparatus for transporting containers of claim 17 wherein: the transverse cross-sectional dimension is at least about twice the spacing between each of the circular arrays to adjacent apertures.

19. The apparatus for transporting containers of claim 18 wherein: the first circular array of apertures is arranged as a first column of apertures and the second circular array of apertures is arranged as a second column of apertures;

said openings in said first column of openings being equally spaced from one another and midway between said lateral side walls defining said first shallow groove;

the openings in the second column of openings are equally spaced from each other and are located midway between the lateral side walls defining the second shallow groove.

20. The apparatus for transporting containers of claim 1, wherein: said suction members being arranged in a single row as they pass through said first transfer zone, said mandrels being arranged in a single row as they pass through said first transfer zone;

the spacing between adjacent spindles is substantially greater than the spacing between adjacent suction members in the transfer zone, and the linear velocity of the spindles is substantially greater than the linear velocity of the suction members.