US 3451523 A
Description (OCR text may contain errors)
June 24, 1969 I s V S JR" ET AL 3,451,523
CONTAINER ORIENTER Filed July 14. 196'? Sheet of 4 INVENTORS JOHN S. EVANS, JR. JAMES E. MCGHEE ATTORNEY June 24, 1969 5, V N JR, ET AL CONTAINER ORIENTER Sheet Filed July 14. 1967 INVENTORS JOHN S. EVANS, JR. JAMES E. MCGHEE ATTORNEY June 24, 1969 5, EVANS, JR ET Al. 3,451,523
CONTAINER ORIENTER Sheet Filed July 14, 1967 qmipm-v mvswroks JOHN s. EVANS, JR 7 JAMES E. McGHEE m: motu a u in @5340 9. 9 0238 mm. mewawm m9 NEE- 553 124 6 Pmwmm ATTORNEY United States Patent US. Cl. 19833 9 Claims ABSTRACT OF THE DISCLOSURE Cans of food are to be oriented for packing in an opensided carton so that selected portions of the can labels face outwardly and are visible to retail purchasers. The labelled cans are conveyed to a large rotating disc of the star-wheel type defining curved pockets for holding the cans in predetermined peripheral positions on the disc, but free for relative rotation with respect to the disc. The centrifugal forces generated by the rotating disc force the cans outwardly against a fixed wall that partially encircles the disc, and the dragging effect of the wall causes the cans to rotate on the disc until each has a predetermined orientation with respect to the disc axis. While the cans are rotating on the disc, a photoelectric viewing apparatus senses a predetermined portion of the label and actuates a clamp to lock the can in its desired orientation and prevents further rotation of the can on the disc. Arriving at a discharge point, each can is automatically unclamped and discharged onto an output conveyor for transmission to the packing station, each of the cans on the output conveyor having a desired label orientation.
BACKGROUND OF THE INVENTION Field.Conveyors, Power-Driven, particularly Orienting Articles on Conveyors (19833).
Prior art.Cans of food or beverage have previously been packed for shipment to retail merchants in large cartons, from which the cans are removed for display on shelves to retail purchasers, so that oriented packing has not been necessary. Some beverages have been displayed for retail in six-pack carrying cartons with handles, so that the customer can carry away six cans at once. However, six-pack cartons have generally had closed sides that hide the labels of the cans, and oriented packing has not been necessary. Now, however, it has been proposed to provide six-pack cartons, and orienting of the can labels to face outwardly is desirable for the sake of appearance and identification.
SUMMARY OF THE INVENTION The object of the invention is to orient containers with selected portions of the labels facing in predetermined directions. Accordingly, the labelled cans are conveyed to a large rotating disc of the star-wheel type defining curved pockets for holding the cans in predetermined peripheral positions on the disc, but free for relative rotation with respect to the disc. The centrifugal forces generated by the roating disc force the cans outwardly against a fixed wall that partially encircles the disc, and the dragging effect of the wall causes the cans to rotate on the disc until they all have the same orientation with respect to the disc axis. As each can arrives at the desired condition of orientation, a predetermined portion of the label is sensed by a photoelectric viewing apparatus, which actu- 3,451,523 Patented June 24, 1969 ates a clamp to clamp the can to its pocket and prevent further rotation on the disc. Arriving at a discharge point, each can is automatically unclamped and discharged onto an output conveyor for transmission to the packing station, all the cans on the output conveyor having the same label orientation.
THE DRAWINGS FIGURE 1 is a cross-sectional plan view of an apparatus in accordance with the invention, the view being taken on a plane of lines 1-1 of FIGURE 2;
FIGURE 2 is a cross-sectional elevation view taken on the plane of lines 22 of FIGURE 1;
FIGURE 3 is a circuit diagram of a portion of the invention shown in FIGURES 1 and 2; and
FIGURE 4 is a wave diagram and timing chart illustrating the operation of the circuit of FIGURE 3.
DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring now to the drawing and particularly to FIGS. 1 and 2, there is shown an apparatus 12 for orienting a number of containers 13a, 13b, 13c, 13d, 13c, 131, 13g, 13h, 13i, 13f, 13k, 13l and 13m so that predetermined portions of the labels face in the same direction. Since the tops of the cans do not have labels, this predetermined portion cannot be shown in FIG. 1, but is indicated schematically on each can by a dot 14, it being understood that the dot '14 does not actually appear on the top of the can. As an example of what the predetermined portion of the label may actually look like, in FIG. 2 the label of e.g. can 13b is shown as made up of a generally blue portion 16 and a generally white portion 17 divided by a vertical interface 18 so that the can in counterclockwise rotation as shown by arrows 19 (FIG. 1) would present to a viewer a change of color from white to blue as the interface 18 passes from left to right across the viewers field of view. The dot 14 corresponds in each case to the border 18. Another interface 21 representing a change of color from blue to white is shown on can 13g of FIG. 2, but this interface will not be used in the example of the present description for determining the orientation of the can. It will be understood of course, that the problem to be solved in the orientation of any array of cans depends in part upon the pictorial or descriptive label that is to be used on the can, but in almost every label there is a unique portion defined by an interface 18 between two colors, so that the apparatus 12 described below needs only to be adjusted in the optimum manner to take advantage of color changes presented during the rotation of any can label.
In the example shown, the cans 13 are conveyed in serial order but in random orientation upon a conveyor belt 22 to and along a flanged feeding station chute 23, which feeds the cans tangentially onto the periphery of a rotating element here shown as a disc 24 mounted on a hollow shaft or sleeve 26, which is in turn fixed for rota-' tion on a drive shaft 27. The disc 24 is described as of the star-wheel type, in that formed thereon are nearly semicircular upstanding flanges 28 spaced around the periphery of the disc and each presenting a concave side facing radially outwardly to define pockets for holding the cans 13 in predetermined peripheral positions on the disc 24, but free for rotation with respect to the disc. The disc rotates in a counterclockwise direction as indicated by the arrow 29 at a sufficient rotational speed that, as the cans arrive on the disc, they are thrown radially outwardly by centrifugal forces, and frictionally engage a curved flange 31 that is fixed in position around the periphery of the disc 24. The dragging effect of the flange 31 causes the cans to rotate with respect to the disc as indicated by the arrows 19, until the predetermined portion of the label (spot 14) faces the axis 32 of the disc. -At this point in the process, each can has the desired orientation, and steps are then taken to stop the rotation of the can with respect to the disc 24 and to hold the can in the desired orientation until it can be discharged from the disc.
The means for stopping the rotation of the can on the disc is here shown as including a clamp member 33 for each can position on the disc, the clamp member consisting of an upstanding pin 34 extending from a pivoted lever 36 on the underside of the disc and arranged to swing in an arcuate slot 37 in the disc so as to engage the lower rim of the can when the can arrives in its orienting position and clamp the can against its corresponding pocket flange 28, thus locking the can against further rotation with respect to the disc. The lever 36 is actuated when clamping is desired by means of a compressed air cylinder 38, which is mounted on the underside of the disc by means of a bracket 39. Each pin 34 has a retracted position (e.g., the pins corresponding with cans 13a, 13b, 13c, 13d, 13e, 13g, 13 13k and 13l in which the pin is withdrawn sufficiently to permit feeding and discharge of the cans to and from the pockets, and a clamping position (as shown for cans 13 13h and 131') in which the pin clamps the can against the pocket flange 28. Means are provided for automatically unclamping each can when it arrives in the position of can 13 so that the can can be discharged onto a discharge chute 41 and a discharge conveyor belt 42. Of course, as the cans are unclamped and discharged, each undergoes further rotation as by engaging the flange 43 of the discharge chute, but the degree of rotation for each can between the discharge station (131') and the conveyor 42 is substantially the same, so the cans nonetheless all end up on the conveyor 42 with the desired predetermined orientations.
For the sake of exemplary illustration, the arc 44 as shown on FIG. 1 represents the rotation acceleration zone within which the can is brought to full rotational speed with respect to the disc 24. The are 46 represents a zone in which each can undergoes at least 360 of rotation with respect to the disc; arc 47 represents 720 of rotation; and arc 48 represents the effective scan and lock zone for the cans on the disc.
The means by which correct orientation of the cans on the disc is sensed, for the operation of the clamp member 33, is shown as including a number of individual photoelectric sensing devices 51 extending from a central housing 52 that is mounted on the disc around the sleeve 26. Each of the sensing devices 51 is directed at an elongated vertical slot 53 formed in the middle portion of the corresponding pocket flange 28; and a toroidal fluorescent light tube 54 is mounted on the housing 52 above the photoelectric elements 51 so as to illuminate that portion of each can that is visible to the photoelectric device through the slot 53. For purposes later to be described, each photoelectric device has formed thereon a normalizing orifice 56 arranged to receive some of the light directed from the tube 54. The photoelectric devices 51 are each connected to circuits for detecting the desired change of color of the can label that has been predeermined for actuating the clamp member 34, these circuits being contained in an electronics housing 57 that is mounted on the sleeve 26 at a higher level. Power connections for these circuits, and certain other connections to be described, are made to fixed electronic elements through a set of slip rings 58 and brushes 59, the brushes being mounted on one or more fixed frame elements 61 and 62. Also mounted on the housing 57 are a pair of magnetic reed switches 63 and 64 for each can position. The switch 63 is used as the reset switch to enable the operation of the detecting and clamping circuits as each can leaves the feeding station (position of can 13d and is a normally open switch that is closed by passage under a permanent magnet 66 that is mounted on the frame 61 at the feeding station. The switch 64 is mounted on housing 57 in a radially more inward position so as not to be operated by the magnet 66, but instead is closed by means of a permanent magnet 67 that is mounted on the frame member 62 as the corresponding can arrives at the discharge station (position of can 131'). The magnet 67 temporarily closes the normally open switch 64 to effect the unclamping action of the clamp member 34. While the magnet 67 is shown as mounted at the feeding station (position of can 13d) and the magnet 67 at the discharge station (position of can 131'), it will be understood that in practice the magnets may be located at any convenient radii of the apparatus 12, so long as the individual can switches 63 and 64 are correctly positioned to be closed when the individual can is at the feeding and discharge stations, respectively.
As shown in FIGURES 3 and 4, each photoelectric device 51 includes an optical detector or photocell 103. The electronics system rot-ates with the star-wheel disc 24, and the can to be oriented rotates with respect to the optic-a1 detector 103 so as to bring the blue-whi'te or white-blue interface across the face of the optical detector. The change in reflectivity experienced by the optical detector causes a positive-going change in the output of the voltage from the optical detector. With the polarity of volage applied to the cell as indicated on FIGURE 3, the cell gives a positive pulse for either a blue-white change or a white-blue change. If the current flow is downward as shown in the figure, a white-blue change generates a positive-going voltage and with the flow upward a bluewhite change gives a positive-going voltage. This positivegoing change is differentiated in a diiferentiator 104 and amplified in an amplifier 105 and applied to one input of a nand gate 106. Also provided are two flip-flops 107 and 109. If flip-flop 109 is not in the set position, the pulse from amplified 105 is applied through nand gate 106 to the set trigger on flip-flop 107. The set output of flip-flop 107 is applied to the input of an amplifier 108, which operates and discharges the voltage on a capacitor 118 so as to operate a solenoid valve 110, allowing air pressure to air cylinder 38 which clamps clamp 34. The star-wheel disc 24 continues to rotate until the unclamp switch 64 passes in proximity to fixed magnet 67, which resets flip-flop 107 and takes the applied voltage ofl? input to amplifier 108, which turns off and releases solenoid valve 110. Air cylinder 38 is retracted by a spring 111, releasing the can 13 to conveyor belt 42.
The operation of flip-flop 109 is as follows: with reference to timing chart FIGURE 4 the opposite polarity of signal is generated in the amplifier 108 at the time of clamping signal. This positive pulse is applied to the set side of flip-flop 109 which is then set and disables nand gate 106 so that no further changes generated by the optical detector can generate false triggers into the clamping system. At the time of unclamp and release of the can from the starwheel there is a dead time on the machine which continues until the star-wheel rotates to the can feeding station. At this time, rese't switch 63 passes in proximity to magnet 66 and is closed to reset flip-flop 109 and to enable and gate 106 so that viewing signals will pass through the system to actuate the clamping mechanism for the next sequence of detection and clamping.
The RC network 117 and 118 operates as follows: during the above mentioned dead time, capacitor 118 charges up to peak applied voltage. At time of clamp the high voltage from the capacitor 118 is discharged through the solenoid at a high instantaneous current rate to overcome the initial magnetic and mechanical inertia of the valve armature. After discharge, the holding current on the solenoid drops to a value, determined by the applied voltage and series resistance 117, resulting in the minimal power dissipation in the clamping electronics and power supply.
The normalizing orifice 56 in the photoelectric device 51 operates as follows: the photocell 103 habitually takes on a voltage level representative of the last illumination level experienced. During the dead time, previously mentioned, the cell 103 receives ambient light and reflections from miscellaneous objects. These may cause the cell to take on a volt-age representative of the relative reflectivity experienced just before it enters active time and begins to scan the surface of the can to be oriented. As the cell varies in output between two limits 'of voltage high and low, a direct ray from the light source 54 is bled into the cell through the orifice 56 to light bias the cell to a voltage level approximately halfway between the limits of positive and negative excursion created by the change in reflected light from the can 13. This bias minimizes the swing created by extraneous objects and lets the cell work the wide swing range when viewing the reflectivity changes. A reflective surface 120 creates an even illumination on the can 13, whereas the direct ray through the orifice 56 comes from a point source adjustable in intensity through the limits required to maintain the cell output at an average value, when not viewing the object.
It will be clear that when a sensing is made of the predetermined portion of the label, the actuation of the clamp member 33 to lock the can may be delayed for any desired time delay by appropriate preadjustment of the circuit for actuating the clamp. This arrangement can be used for the purpose of giving certain of the cans in a given sequence different orientations that the remaining cans of the sequence, although the identical color interface is sensed on each can label.
Thus there has been described an apparatus for orienting containers with selected portions of the labels facing in predetermined directions. The labelled cans are conveyed to a large rotating disc of the star-wheel type defining curved pockets for holding the cans in predetermined peripheral positions on the disc, but free for relative rotation with respect to the disc. The centrifugal forces generated by the rotating disc force the cans outwardly against -a fixed wall that partially encircles the disc, and the dragging efllect of the wall causes the cans to rotate on the disc until they all have the same orientation with respect to the disc axis. As each can arrives at the desired condition of orientation, a predetermined portion of the label is sensed by a photoelectric viewing apparatus, which actuates a clamp to clamp the can to its pocket and prevent further rotation on the disc. Arriving at a discharge point, each can is automatically unclamped and discharged onto an output conveyor for transmission to the packing station, all the cans on the output conveyor having the same label orientation.
What we claim is: 1. An orienting machine for containers, comprising: means for rotating each container separately to bring a predetermined marked portion of said container to a predetermined orientation;
said rotating means including a rotating element, means formed thereon for holding said containers in predetermined peripheral positions thereon but free for rotation with respect to said rotating element, and means engaging said containers and causing rotation of said containers with respect to said rotating element;
sensing means arranged to view each of said containers and to emit a corresponding signal when said predetermined marked portion of each container arrives at said predetermined orientation; and
means coupled to said sensing means for stopping the rotation of each container upon reception of said corresponding signal;
said stopping means including a movable clamp member mounted on said rotating element near each container for movement between a retracted position away from said container and a clamping position clamping said container with respect to said rotating element.
2. The combination recited in claim 1, wherein said sensing means includes:
a photoelectric sensing device for each of said predetermined peripheral positions of said rotating element, said devices being mounted on said rotating element for rotation therewith; and
light source means for illuminating each of said cans throughout a predetermined field of view of said photoelectric device.
3. The combination recited in claim 2, and also includcontainer feeding means located at a predetermined fixed feeding station on the peripheral path of said rotating element for feeding said containers to said rotating element;
container discharge means located at a predetermined fixed discharge station on the peripheral path of said rotating element for discharging said containers from said rotating element;
said feeding and discharge stations being spaced peripherally around said rotating element for a suflicient distance to ensure that each container arrives at said predetermined orientation before arriving at said discharge station; and
means mounted at said discharge station for actuating each of said clamping members on arrival at said discharge station so as to unclamp the respective container to free said container for discharge.
4. The combination recited in claim 3, and also including:
means mounted at least in part on said rotating element for disabling each of said corresponding clamp members from being operated for clamping action more than once during each revolution of said rotating member from said feeding station to said feding station.
5. The combination recited in claim 4, wherein said last-named means includes:
means for receiving said signal from each of said photoelectric sensing devices at the moment when the corresponding container is clamped, and for disabling the corresponding clamp member from being operated again for clamping action at least until said corresponding clamp member has returned to said feeding station; and
means for relieving said disabling means so as to again permit clamping action of each clamping member as said clamping member begins a new revolution from said feeding station.
6. The combination recited in claim 5, wherein:
said photoelectric device is mounted in a housing having an aperature formed therein for transmitting direct light from said light source to said photoelectric device for normalization thereof.
7. The combination recited in claim 6, wherein:
said clamp member includes an actuating solenoid coupled to receive said signal from said sensing means; and
a power source an capacitor coupled in series to said solenoid for discharge of said capacitor upon energization of said solenoid by said signal and for imparting an additional energizing impulse to said solenoid.
8. The combination recited in claim 1, wherein:
said means for engaging and rotating said containers includes a flange fixed in position at the periphery of said rotating element and engaged by said containers under the influence of centrifugal forces generated by the rotation of said rotating element.
9. The combination recited in claim 7, wherein: References Cited sai i means for engag1ng and tota'tmg 531d containers UNITED STATES PATENTS includes a flange fixed in position at the periphery of said rotating element and engaged by said containers 5 1938 Rueunder the influence of centrifiugal forces generated by the rotation of Said rotating element 5 E. Primary Examiner.