LABEL TRANSFERRING APPARATUS FOR BLOW MOLDING MACHINES

Abstract: In-mold labeling devices for blow molding machines and in particular to label transferring devices which place labels simultaneously in separate sides of the molds. One difficulty with such label application is to keep the label transfer time at a minimum in order to reduce the amount of time that the molds remain open. The device comprises a carriage (40) mounted on a piston rod (32), and a hydraulic cylinder (30) so as to extend the carriage between separated mold sections (16) and retract to between a set of label supply magazines (60). The label magazines are positioned so that a set of opposed carrying cylinders (42a) can extend and pick up the labels on carrying heads (46a) and place the labels in the mold sections. Alternatively, the carrying cylinders are mounted on a pair of extendable, converging clamp arms (70) which clamp onto the molded objects, remove them from the molding area and transport them to other processing stations. In another arrangement, an articulating arm (40), including a vacuum section head (92),and a label supply (100) are mounted on a mold platen (10) so that both the arm and label supply are carried by the platen as it moves to different blow molding stations. The arm moves the head from the label supply to between the molds.

Description: - - LABEL TRANSFERRING APPARATUS FOR BLOW MOLDING MACHINES BACKGROUND OF THE INVENTION The present invention relates to in-mold labeling devices and in particular to label transferring devices which are used in blow molding machines having separable molds carried on a pair of platens. Blow molding machines having various designs are well known in the art. Many of these blow molding machines utilize a pair of spaced, movable platens which have mating mold sections mounted on their facing surfaces. These machines may utilize a single work station at which a parison of molding material is extruded or otherwise formed and then clamped between the mold sections. The object to be molded, such as a bottle or the like, undergoes the blow molding process at that station, after which the mold sections separate and the bottle is released. Other machines utilize several work stations and the platens are movable between the different work stations so that the machine can service several molds at the same time. It is desirable in blow molding containers to in-mold labels. This process consists of placing the container labels within the mold cavity prior to the blow molding process. The label is thus attached to the bottle during the molding process and proper placement and adhesion are assured. One difficulty experienced with such in-mold label application is that label transfer time must be kept at a minimum in order to reduce the amount of time that the mold sections must remain open. Any delay in the closing of the mold sections increases the cycle time for the blow molding OMPI process and thus reduces the productivity of the machine. Heretofore, various methods of placing labels into separable molds have been utilized. These have included the use of a label carrying arm which extends between the separated mold sections when they are open, and the use of a special label insert aperture in the mold through which the label is punched into position. The present invention is an improvement to the former type of method, the present state of the art being illustrated, for example, by United States Patents 3,072,969, issued January 15, 1963; 3,292,209, issued December 30, 1966; and 4,355,967, issued October 26, 1982. Additionally, manufacturing costs are increased for the handling of blow molded objects when they are not properly oriented upon removal from the blow molding machine. Separate handling machines are required to sort and properly orient the objects so they can be used. Such additional procedures are costly and time consuming. • SUMMARY OF THE INVENTION The present invention is embodied in a label transferring device which is used to place labels in the mold of a blow molding machine. The mold has separable sections which are carried on converging platens which are supported on a machine frame. A label carrying head includes a means for holding onto the labels, but which also permits the labels to be removed from the carrying head when required. Mounted on the machine frame is a reciprocating extender assembly which includes an extendable element which may be shifted only in a straight line along a longitudinal axis. The means which shifts the extendable element shifts the extendable element between a withdrawn position OMPI -3- away from the platens and an extended position between the mold sections. The label carrying head is supported on the extender assembly by a means which shifts the head into a mold section when the extender assembly is extended. The label carrying head is supplied with labels from a means mounted on the machine frame when the extender assembly is withdrawn. The label carrying heads may be mounted on a pair of clamping arms which extend between the mold sections. The clamping arms remove the blow molded objects and transports them to other processing stations in the blow molding machine while the label carrying heads place the labels in the mold sections. The present invention allows for the rapid placement of labels within mold sections since the carriage assembly or clamping arms are only required to be moved linearly between the label supply and the mold sections. The smaller carrying heads can then be rapidly employed due to their small size and comparably small mass. Due to the one-dimensional movement of the carriage assembly, complex mechanisms which would result in complicated and time-consuming motion are not required. The device produces a compact design which can be mounted directly to existing machines rather than requiring a free-standing support or otherwise requiring a large amount of operating room. The uncomplicated straight-line movements of the respective elements permit easy assembly and installation upon a machine while maintaining proper alignment with the mold sections. The present invention also includes label transferring device mounted directly to one of the platens so that it is carried with the mold -4- sections as they are moved between the different blow molding stations. The transferring device includes a carrying head for the label, a means to position the carrying head between the separated mold sections and a means to transfer the label from the carrying head to the proper location in the mold. A label supply is also carried on the platen so that the carrying head can move between it and the mold as the platens shift between stations. Preferably, a second label applying assembly is mounted on the other platen so that a label can be placed in both sides of the mold when so desired. With the above device, the mechanism which places the label within the mold is always maintained in registry with the mold. This relieves any misalignment problems experienced with other label transferring techniques. Further, this labeling device reduces the cycle time for the blow molding machine, since the labelling device can be placing a label into the open mold while the platens are moving the mold between different stations on the machine. Therefore, the platens are not required to remain stationary after discharging the previous set of bottles, but may immediately begin moving toward a new parison to start a new molding cycle. These and many other aspects and objects of the invention will be recognized by those skilled in the art from the description, claims and drawings which follow. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a fragmentary plan view of a label transferring device and a pair of platens with mold sections mounted thereon in a separated position showing a preferred embodiment of the invention; Fig. 2 is a fragmentary plan view of the device of Fig. 1, shown with the label carrying heads fully extended to pick up a set of labels; Fig. 3 is a fragmentary plan view of the device of Fig. 1, shown with the carriage assembly extended between the separated mold sections and the label carrying heads fully retracted each with a label carried thereon; Fig. 4 is a fragmentary plan view of the device of Fig. 3, shown with the label carrying heads fully extended placing the labels within the separated mold sections; Fig. 5 is a fragmentary plan view of a second preferred embodiment of the invention, showing a label transferring device mounted on a pair of bottle removal arms with the arms retracted; Fig. 6 is a fragmentary plan view of the device of Fig. 5, shown with the clamp arms extended and the transferring device placing a set of labels in the mold sections; Fig. 7 is a fragmentary plan view of the device as positioned in Fig. 6 taken along plane VII-VII, showing a pair of clamp arms extended around a set of blow molded bottles; Fig. 8 is a view of the device taken along plane VIII-VIII of Fig. 6, shown with the label transfer device having already placed the labels in the mold and a blow pin holding the bottle; and Fig. 9 is a fragmentary view of the device taken along plane IX-IX of Fig. 5, shown with the label transfer device prior to picking up a new supply of labels. Fig. 10 is a side-elevational view of another embodiment of a label transferring device embodying the present invention, shown with the platens separated and the device applying a set of labels to the mold; Fig. 11 is a side-elevational view of the device of Fig. 10, shown with the platens and mold sections closed together and the label transferring device obtaining a new label from the label supply; Fig. 12 is a front-elevational view taken along part line III-III of Fig. 11 in between the separated mold sections with the transfer device shown in phantom in a label applying position; and Fig. 13 is a side-elevational view of another embodiment of a label transferring device used to transfer labels to only one side of a mold, shown in phantom with the device placing a label into the mold. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In the two preferred embodiments shown in Figs. 1 and 5, a label transferring device 1 has either a carriage 40, Fig. 1, or a part of arms 70, Fig. 5, which are slidably mounted so as to be extended from their at-rest position between a set of label supply magazines 60, Figs. 1, 5, to a position between a pair of mold sections 16 mounted in a blow molding machine, Figs. 3, 6. Carried on carriage 40 and arms 70 are a set of opposed label carrying vacuum heads 46 which can be extended from the sides of carriage 40 or arms 70 in order to pick up a new set of labels, Figs. 2, 5, and to apply these labels to both mold sections 16 simultaneously, Figs. 4, 6. Since transferring device 1 has a label supply 60 which is linearly aligned with the mold sections 16, carriage 40 and arms 70 are only required to reciprocate back and forth between the label pick-up and label applying stations, thereby reducing other extraneous OMPI -7- move ents and reducing the time required for a single labeling cycle. In the embodiment of Fig. 5, clamp arms 70 are additionally used to withdraw the blown bottles from between the mold sections 16 to transport the bottles to ther processing stations in the machine. EMBODIMENT OF FIGS. 1 - 4 Transferring device la, as shown in Figs. 1-4, is used with a molding assembly 10 which has a pair of spaced, movable platens 12 which are slidably mounted on a set of tie rods 14, Figs. 1-4. Platens 12 slide on tie rods 14 in order to converge and separate mold sections 16 mounted on facing surfaces thereof. Platens 12 may also be mounted within the blow molding machine to move from one blow molding station to another during the molding process — i.e., from an extrusion station where the mold sections are closed on the parisons to a calibration station where blowing of the parisons is effected. This allows the use of multiple molds with a single extrusion station-. Mold sections 16 each include a pair of mold cavities 18 which are configured to mate with the opposing mold cavity 18 and shape the blown object during the blow molding process; Running through platens 10 are cooling manifolds (not shown) which communicate with a mating network of cooling ducts located in mold sections 16 (not shown), as is conventionally known in the art. Within each mold cavity 18 is a label mounting surface 19 on which the label is placed in order to be properly aligned on the finished bottle. Label mounting surfaces 19 are underlaid by a network of vacuum channels 20 which extend through label mounting surfaces 19 and hold the label in place during the molding process. Vacuum channels 20 are negatively -8- pressurized by a flexible vacuum supply hose 22 which extends to a suitable vacuum source of any conventional type. Carriage 40, Figs. 1-4, is mounted on a positioning hydraulic cylinder 30 which includes a nonrotation piston rod 32 which extends carriage 40 in cantilever fashion. Figs. 3, 4. Positioning hydraulic cylinder 30 is mounted on the blow * molding machine frame 300. Hydraulic cylinder.30 is oriented to extend piston rod 32 in horizontal registry with magazines 60 and label mounting surfaces 19. It is also directed along the plane- in which part line 33 lies, part line 33 being the line at which the mating face of mold sections 16 about when the mold is closed. Piston rod 32 is sufficiently long so as to position carriage 40 between mold sections 16 when hydraulic cylinder 30 is extended. Fig. 3. Cylinder 30 is a double-acting oil cylinder which is controlled by a suitable oil pressure supply 34, such as through flexible hoses or the like. Mounted on hydraulic cylinders 30 is a full-out limit switch 36 which is contacted when piston rod 32 is fully extended and, thus, when vacuum heads 46 are in longitudinal registry with label locations 19 in cavities 18. Mounted on the mold facing side of cylinder 30 is a full-in limit switch 38 which senses when carriage 40 has been fully withdrawn from between mold sections 16, Figs. 1-2, and, thus, when vacuum heads 46 are in longitudinal registry with label magazines 60. Limit switches 36 and 38 are used in the control of label transferring device la as is described below. As shown in Figs. 1-4, carriage 40 has an overall rectangular shape on which two sets of placement hydraulic cylinders 42a are mounted in OMP -9- opposition. Carriage 40 is coupled to piston rod 32 by conventional means, such as a threaded coupling or union 43. Placement cylinders 42a each have a rod 44a and are mounted to extend a vacuum head 46a mounted on rod 44a away from the side of carriage 40, Figs. 2,4. Two vacuum heads 46a are mounted on either side of carriage 40 and are aligned generally parallel to the line of movement of positioning cylinder rod 32. The pair of vacuum heads 46a on each side are spaced approximately equal to the spacing between the two label mounting surfaces 19 on each mold so that vacuum heads 46a may simultaneously place a label on mounting surfaces 19. So mounted, each vacuum head 46a operates in opposition to another head 46a. Each vacuum head 46a is supplied a vacuum across its flexible cup-shaped outer face by flexible vacuum supply hoses 48a which all join a common vacuum supply manifold 49a. Manifold 49a is supplied vacuum by suitable means, such as a flexible hose connected to a suitable vacuum source. Mounted on carriage 40 are four full-in limit switches 50a, each of which is tripped by a lobe 51a on rod 44a when hydraulic cylinder 42a is fully retracted. Fig. 1. Limit switches 50a are utilized in the control of the label transferring device described infra. Mounted to the blow molding machine frame are four label magazines 60, Figs. 1-4. Two label magazines 60 are suitably mounted on each of a pair of support bars 61 in any conventional manner located on opposite sides of carriage 40 when in a retracted position. Figs. 1-2. Magazines 60 are mounted so as to be longitudinally aligned wih placement hydraulic cylinders 42a when positioning cylinder 30 is retracted. Fig. 1, so that vacuum -10- heads 46a will be extended toward and contact the open ends of label magazines 60 as placement cylinders 42a are activated. Label magazines 60 have an open end 62 through which a supply of labels 64 are accessible by vacuum heads 46. Labels 64 are stacked in magazine 60 and are urged toward open end 62 by a spring. The labels are retained within magazine 60 by an annular flange or lip at open end 62. Open ends 62 are aligned generally in the same vertical plane as label mounting surfaces 19 on the open mold sections 16. Both label magazine open ends 62 and label mounting surfaces 19, thus, are spaced approximately the same distance from the path of travel of carriage 40. Both magazines 60 and mounting surfaces 19 may be accessed by vacuum heads 46a when rods 44a are fully extended. OPERATION In operation, label transferring device la will simultaneously place labels 64 in the four mold cavities 18. It will then retract, pick up four more labels and place them in the cavities once the blowing operation has been completed. At the beginning of the cycle, carriage 40 is retracted from platens 12 and placement cylinders 42a are retracted, as shown in Fig. 1. Mold sections 16 may be separated, as shown in Figs. 1-2, or may be closed and undergoing the blowing process for bottles from the previous cycle. When carriage rod 40 is fully retracted, limit switch 38 activates hydraulic cylinders 42a which extend. rods 44a and vacuum heads 46a until they contact label magazine open ends 62 as shown in Fig. 2. A vacuum is continuously supplied across the cup faces of vacuum heads 46a to secure labels 64 to heads 46a. Placement cylinders 42a are extended for a :timed duration and then retracted, with vacuum heads 46a removing the outermost labels 64 from label agaznes 60, as is well known in the art. With mold sections 16 separated, when limit switches 50a sense that vacuum heads 46a have been retracted, positioning cylinder 30 is activated and piston rod 32 is extended to move carriage 40 between mold sections 16, Fig. 3. Vacuum heads 45a with the attached labels 64 are thus brought into lateral alignment with label mounting surfaces 19. When piston rod- 32 is fully extended, limit switch 36 activates placement cylinders 42a to extend rods 44a as shown in Fig. 4. Vacuum heads 46a press labels 64 against the label mounting surfaces 19, where they adhere due to a vacuum which is constantly supplied through channels 20. Placement cylinders 42a extend vacuum heads 46a for a timed duration after which vacuum heads 46a are withdrawn. The vacuum supplied to vacuum channels 20a underlying label mounting surfaces 19 is greater than the vacuum at vacuum heads 46a, so that as heads 46a retract, labels 64 are removed from heads 46a and adhere in proper registry to mounting surfaces 19. When heads 46a have fully retracted, limit switches 50a activate positioning hydraulic cylinder 30 to retract piston rod 32 and carriage 40, Fig. 1. Limit switch 38 will activate placement cylinders 42 for the start of a new cycle. At this or during the same time, mold sections 16 can be transferred and/or converged by platens 12 to converge around the parisons. EMBODIMENT OF FIGS. 5 - 9 As shown in Figs. 5-9, a label transferring device lb is used to transfer labels into the mold sections 16, and to remove the set of bottles 2 which are the re -12- fro between mold sections 16. Label transferring device lb is particularly suited to blow molding machines in which bottle removal between the bottoms of platens 12 is prevented, such as in blow molding machines which utilize platens which are pivotally moved between various processing stations in the blow molding machine. These platens include tie rods located beneath mold sections 16 which prevent the bottles from being ejected downwardly. As shown in Figs. 5, 6, molding assembly 10 has a pair of spaced, movable platens 12 which carry a mating pair of mold sections 16. Mold sections 16 have a pair of mold cavities 18 with label mounting surfaces 19 which are underlaid by vacuum channels 20 as described in connection with the previous embodiment. A pair of a elongated bottle clamping arms 70 are used to walk bottles 2 from between mold sections 16. As shown in Figs. 5 and 6, arms 70 each have three clamp elements 72 which are grouped in opposing pairs on the two arms 70. Each clamp element has a concave, bottle-conforming surface 74 bounded by inwardly converging flanges 75 which form a pair of bottle clamping seats. The finished containers are walked by clamps 76 from the calibration station 110 to the label supply station 112; by clamps 78 from the label supply station to the deflashing station 114, and by clamps 80 onto conveyor 120. Clamping arms 70 are converged, retracted and reciprocated by assembly 88, Fig 9. A spaced pair of vertical support arms 89 rigidly depend from arms 70. Support arms 89 are slidably mounted to a pair of horizontal, laterally directed slide rods 92 upon which arms 89 are converged and retracted to clamp onto and release bottle 2 as is OMP -13- conventionally known in the art. Carriage elements 94 support slide rods 92, arms 70 and 89. Elements 34 are mounted for longitudinal sliding movement on rods 96 in a conventional manner. Lateral and longitudinal motion is imparted to the arms 70, typically, by hydraulic cylinders. Extending parallel to and below clamping arms 70 between support arms 89 is a pair of support brackets 100 which form a support stand for bottles 2 when clamp arms 70 are released. Brackets 100 are spaced to provide a slot 101 which accommodates flash 116 located on the bottom of the bottle. Brackets 100 are each mounted to the blow molding machine by a mounting bracket 102. Mounted on each clamping arm 70 opposite clamps 76 and facing outwardly are a pair of placement hydraulic cylinders 42b, Figs. 5-6. Cylinders 42b have extending rods 44b with vacuum heads 46b carried thereby, as described in relation to the embodiment of Figs. 1-4. Vacuum heads 46b are provided with a vacuum across their flexible, cup-shaped outer surface by vacuum supply hoses 48b which are coupled to a vacuum supply manifold 49b on each clamp 70. Limit switches 50b are tripped by lobes 51b on rods 44b when cylinder 42b are retracted. Placement cylinders 42b are positioned on each clamping arm 70 such that the longitudinal spacing therebetween corresponds to the longitudinal spacing between label mounting surfaces 19 of mold cavities 18 and label magazines 60. Placement cylinders 42b extend from clamp arms 70 to contact and place labels on label mounting surfaces 19 in both mold sections 16 simultaneously when arms 70 are extended between mold sections 16. OMPI -14- At label station 112 are mounted four label magazines 60 which provide vacuum heads 46b with labels 64 as described in relation to the embodiment of Figs. 1-4. Label supply station 112 also serves as a cooling station within the low molding machine for bottles 2. Bottles 2 must be cooled prior to the trimming of flash. If the bottles 2 are too hot, the flash deforms rather than cutting cleanly. Located to the side of label supply station 112 opposite calibration station 110 is a deflashing station 114. Flash is trimmed from the tops and bottoms of bottles 2 by trimming elements 118 in conventional fashion, the trimming elements converging above and below arms 70. OPERATION Label transferring device lb simultaneously places labels in both sides of mold cavities 19 and removes the bottles formed in the previous blow molding cycle from the calibration station. At the start of a cycle, arms 70 are withdrawn from between mold sections 16 as shown in Fig. 5. Arms 70 have just separated, releasing bottles 2 from the previous cycles of the blow molding machine. Placement cylinders 42b are activated in order to extend piston rods 44b and vacuum heads 46b toward label magazines 60. Vacuum heads 46b contact a new set of labels 64 and after a timed duration are retracted, removing labels 64 which are held on heads 46b by the continuous vacuum. After mold sections 16 have separated leaving a pair of bottles 2 suspended from blow pins 122, Fig. 8, arms 70 are extended between mold sections 16 as shown in Fig. 6. Placement cylinders 42b are then extended to place labels 64 on label mounting surfaces 19. After a timed duration, placement cylinders 44b retract. The greater vacuum applied by vacuum apertures 20 causes labels 64 to adhere in proper registry to mounting surfaces 19. When limit switches 50b sense the full retraction of piston rods 44b, clamping arms 70 are converged on rods 92 and clamps 76 seize the bottles 2. Clamps 78 and 90 simultaneously clamp the bottles which resulted from the previous two molding cycles. Clamp arms 70 are withdrawn from between mold sections 16 and clamp arms 70 separate, releasing bottles 2. While the mold sections 16 close about the parisons to form a new set of bottles, the bottles 2 at label supply station 112 cool in preparation for deflashing. Simultaneously, placement cylinders 42b are activated to pickup another set of labels 64 for the next cycle. Flash trimming elements 118 trim the flash from the bottles 2 at deflashing station 114, and conveyor 120 conveys the bottles 2 placed on it away from the blow molding machine. It will be understood by those skilled in the art that label transferring device lb may be used to transfer bottles 2 to other operational stations as well as those listed above. Also, clamping arms 70 could be separated in order to shift vacuum heads 46b toward label magazines 60 and label mounting surfaces 19, so that vacuum heads 46b could be fixedly mounted on clamping arms 70. Other label supplies could be used, such as continuous rolls of label strips, instead of the stacked label magazines 60 which urge the labels toward the open end 62. In the embodiment shown in Figs. 11-13, label transferring devices 1 and la are mounted directly U OMPFII - VVvV'' -16- to each of a pair of spaced, movable platens 10, 10a so as to move with the platens as they shift a pair of mold halves 14, 14a between different stations in a blow molding machine,. Label transferring devices 1 and la are used to place container labels in mold halves 14, 14a so that the labels will be attached onto the blown object, such as a bottle or the like, during the blowing process. Label supply magazines 100, 100a are also attached to platens 10, 10a, respectively, so that label transferring devices 1, la may also pick up a new label from magazines 90, 90a while platens 10 and 10a are being shifted. For purposes of these embodiments, label transferring devices 1 and la are mirror images of each other, with the exception that label transferring device 1 is mounted on one of the two spaced platens, while label transferring device la is mounted on the other platen. Therefore, label transferring device 1 will be described in detail along with platen 10 and mold section 14, although it will be understood that the same description applies to the label transferring device la. Platens 10 and 10a are substantially flat plates which are slidably joined by a pair of tie rods at mounts 12, Fig. 12, upon which platens 10 converge and separate. Figs. 10 and 11. Platen 10 has a mold section 14 mounted on its inner facing surface so that platens 10, 10a open and matingly close mold sections 14, 14a in a manner well known in the art. Platens 10 are mounted on the particular blow molding machine in a conventional manner so as to be shiftable between various blow molding stations in the blow molding machine, as well as to allow opening and closing of mold sections 14 and 14a. Platens 10 have cooling -17- manifolds (not shown) which pass from the platen outer surface to mold sections 15 and mate with similar cooling manifolds and bores which extend through mold halves 14. These cooling manifolds are used to circulate cooling fluid through mold sections 14 during the blow molding process and are of conventional design known in the art. Mold half 14, Fig. 12 includes a pair of mold cavities 16 which are each configured to produce a bottle or other object of the desired shape. Within each mold cavity 16 is a label location 20 on which a label is placed to be properly located and affixed to the finished bottle during the blowing operation. Underlying label location 20 is a series of vacuum ports or ducts 18, Figs. 1.0-11 which secure the label to mold section 14, as later described. Ducts 18 communicate ' with vacuum suppl manifolds 19. Vacuum is supplied to manifolds 19 in any conventional fashion, such as by flexible tubing. Label transferring device 1 includes a spacing hydraulic cylinder 30, Fig. 10, which is mounted directly to platen 10 and has a piston rod 32 which slidably extends to the side of platen 10 on which mold section 14 is mounted. Cylinder 30 is connected to platen 10 by a platen mount 34 which may be an integral extension of platen 10 or may be a separate mounting bracket which has been secured to platen 10 by welding or the like. Platen mount 34 rigidly secures cylinder 30 so that label transferring device 1 is maintained in registry with mold section 14 at all times. Cylinder 30 is a double-acting oil hydraulic cylinder and has a nonrotatable piston rod. Movement of piston rod 32 is positively controlled by a properly valved hydraulic fluid su -18- As shown in Figs. lO-ll, secured to the free end of piston rod 32 is a positioning hydraulic cylinder 40. Hydraulic cylinder 40 is rigidly (nonrotatably) mounted on piston rod 32 by a coupling 43. Positioning cylinder 40 is shifted toward and away from platen 10 as spacing cylinder 30 is activated. Preferably, coupling 42 may be a bracket or the like which is screwed onto piston rod 32 by a threaded collar or by other conventional fastening means. Positioning cylinder 40 has a piston rod 44 which extends toward mold 14 from spacer cylinder 30, and is a double-acting oil cylinder having a nonrotatable rod 44 with a centrally mounted piston. Rod 44 is sealed at both extremities of the cylinder and is of sufficient length that extremity 54 will protrude at least slightly from the cylinder when extremity 52 is fully extended. A flexible vacuum supply line 56 is connected to end 54 of rod 44 by a connector 58. Vacuum bores 60 are used to supply vacuum to the carrying elements 92 which carry the labels while they are being placed wihin mold 14. Connected to coupling 42 is a control rod 62, Figs. 10-11, used to determine when piston rod 32 has reached the inner and outer limits of its desired stroke. Control rod 62 is parallel to piston rod 32 and is connected to coupling 42 by a bracket 64 as well as being received through a sliding guide 65 mounted on platen 10. Mounted to platen 10 on either side of guide 65 are limit switches 66 and 67. Lobe 68, adjustably positioned on rod 62, contacts limit switch 66 when piston rod 32 is retracted to the desired extent, Fig. 11. Lobe 69, also adjustably positioned on control rod 62, contacts limit switch 67 when piston rod 32 is extended to the desired extent, Fig. 10. Rod 32 of cylinder 30, in accordance with the preferred embodiment of this invention, travels between fully extended and fully retracted positions, limit switches 66 and 67 triggering other processing steps as hereinafter explained. As will be apparent to those skilled in the art, however, the positioning of rod 32 of cylinder 30 can also be controlled short of the fully extended and fully retracted positions, by limit switches 66 and 67. Limit switch 70 is tripped by extremity 54 of rod 44 when rod 44 is retracted to the desired position. Limit switch 71, similarly, is tripped by extremity 54 when rod 44 is extended to the desired position. Again, in accordance with the preferred embodiment of this invention, these are fully extended and fully retracted positions, activation of the limit switches functioning primarily to initiate subsequent processing steps. As in the case of switches 66 and 67, however, switches 70 and 71 may be used to position rod 44 intermediate these fully extended and fully retracted positions. Mounted on free end 52 of piston rod 44 via carriage bar 82 is a pair of placement hydraulic cylinders 90, Figs. 10-12. Carriage bar 82 is connected to rod 44 by a coupling 84. Coupling 84 rigidly connected carriage bar 82 and hydraulic cylinders 80 to piston rod 44 so that cylinders 80 shift with rod 44 but do not pivot relative to hydraulic cylinder 40. Coupling 84 is preferably mounted on free end 52 by a threaded joint or other conventional connection. A continuation of bore 60 extends through and to the exterior of coupling 84. -20- Cylinders 80 have rods 88 that extend toward platen 10. Placement cylinders 80 are double-acting oil cylinders which each have flexible hyraulic supply lines 90 which lead to a hydraulic fluid supply, pump and attendant valving (not shown). On the ends of the piston rods 88 are flexible vacuum cup heads 92 that have a concave cup-like vacuum surface which is connected by a flexible vacuum supply line 96 to bore 60. Placement cylinders 80 therefore shift vacuum heads 92 toward and away from platen 10. Mounted on platen 10 intermediate spacing cylinder 30 and mold secion 14 is a pair of spaced label supply magazines 100, Figs. 10-12. As shown in Figs. 10-11, magazines 100 contain a stacked supply of labels 102 and are mounted on platen 10 by a pair of mounting brackets 104 so as to extend through platen 10. Magazines 100 have an open end 106, Fig. 10, through which vacuum heads 92 may access labels 102, as in Fig. 11, and an annular retaining flange 108 retains labels 102 within magazine 100. Labels 102 are urged toward open end 106 by a spring or the like (not shown) so that a new label 102 is constantly maintained in contact with retaining flange 108 and accessible through open end 106. Magazines 100 are aligned with label placement locations 20 — i.e.. the magazines appear directly beneath the label placement locations 20 when viewed as in Fig. 12, although they are in fact laterally offset. Vacuum heads 92, thus, maybe simultaneously shifted from a position horizontally aligned with label placement locations 20 to a position horizontally aligned with label magazines 100 by the actuation of positioning cylinder 40, Figs. 10-11. -21- Piston rod 32 of spacing cylinder 30 has a length sufficient that when lobe 69 engages limit switch 67 positioning cylinder 40 will be spaced from platen 10 sufficiently to allow vacuum heads 92 (with rods 88 retracted) to clear mold section 14 as piston rod 44 of positioning cylinder 40 is extended. Fig. 10. However, piston rod 32 should not shift positioning cylinder 40 away from platen 10 past the part line 104 that is a bifurcating plane of the space between platens 10 and 10a, Fig. 10. Should the plane be crossed, assembly 1 would interfere with the operation of assembly la. Piston rod 44 of positioning cylinder 40 has a length sufficient that when extremity 54 contacts limit switch 71, placement cylinders 80 and the vacuum cups carried thereby are positioned in horizontal alignment with label placement locations 20 in mold cavities 16, Fig. 10. Piston rods 88 of placement cylinders 80 have a length sufficient to place a label 102 in contact with label placement locations 20 when fully extended, and label magazine 100 is positioned to be contacted by vacuum heads 92 when cylinders 30 and 40 are both retracted. Fig. 11, i.e., when lobe 68 is in contact with limit switch 66 and extremity 54 is in contact with limit switch 70. An alternative embodiment of the above described label transferring device is shown in Fig. 13 for use in placing labels in only one of mold sections 14. Label transferring device 2 is used to apply labels in only one side of the mold. Label transferring device 2 is identical to that of label transferring device 1, with the exception that positioning hydraulic cylinder 40 is mounted on a stationary support base 120 rather than on spacing cylinder 30. Support 120 is secured directly to platen 10. Label magazine 100b is mounted on platen 10 so that its open end 106b lies in approximately the same vertical plane as label placement location 20. Vacuum heads 92 may then access both label placement locations 20 and label magazines 100 without requiring positioning cylinder 40 to be shifted toward and away from platen 10. OPERATION OF FIGS. 10 - 13 In order to operate label transferring device 1 through a complete cycle of the blow molding machine, label transferring device 1 is first positioned with spacing cylinder 30, positioning cylinder 40 and placement cylinders 80 all retracted, Fig. 11. In this position, a label 102 is already placed on label placement locations 20 and mold sections 14, 14a are closed with the parison undergoing the blowing step at the calibration station. A vacuum is continuously supplied to vacuum heads 92 through vacuum supply lines 56, 96 and hose 60. A vacuum is also continuously supplied to vacuum apertures 18 through bores 19 behind placement locations 20. The negative pressure at manifolds 19 and, thus, ports 18 is greater than that at vacuum head 92. This enables the transfer to a label from a head 92 to a label location 20 without interruption of the vacuum supply to heads 92. With the mold closed and all cylinders retracted, vacuum heads 92 contact the exposed labels 102 in magazines 100. At or about this point in the cycle, blowing of the parison has been completed and the platens are moved to the position shown in Fig. 10 separating the mold halves 14 and 14a. The resulting containers with labels affixed -23- to either side thereof are removed from the calibration station in any conventional fashion. Spacing cylinders 30 and 30a are activated so as to extend piston rods 32 and 32a. Piston rods 32 and 32a do not extend positioning cylinders 40 beyond part line 104 so that label transferring device 1 and la on both side of the platens may be simultaneously activated without interferring with each other. Fig. 11. When piston rods 32 and 32a are fully extended, full out limit switches 67 and 67a are contacted by lobes 69 and 69a on control rods 62 and 62a and positioning cylinders 40 and 40a are activated. Piston rods 44 and 44a are then extended to position placement cylinders. 80 and 80a in horizontal registry with label placement locations 17 and 17a. When piston rods 44 and 44a are fully extended, limit switches 71 and 71a are contacted by protruding ends 54 and 54a of rods 44 and 44a and placement cylinders 80 and 80a are thereby activated. When activated, placement cylinders 80 and 80a extend for a timed duration and press labels 102 and 102a against label placement locations 20 and 20a, Fig. 10. The vacuum supplied to label placement locations 20 and 20a is greater than the vacuum supplied to vacuum heads 92 and 92a so that when rods 88 and 88a retract, labels 102 and 102a are removed from heads 92 and 92a and remain adhered to label locations 20 and 20a. When rods 88 and 88a are retracted after their timed duration, piston rods 44 and 44a on positioning cylinders 40 and 40a are retracted. When full in limit switches 70 and 70a are contacted by protruding ends 54 and 54a, spacing cylinders 30 and 30a are activiated and piston rods 32 and 32a retracted. Mold sections 14 and 14a may then be transferred to the extrusion station and close on a new parison. Note that this transfer may be taking place, if desired, during the period the labels 102 and 102a are being placed in the mold. When piston rods 32 and 32a are fully retracted so that limit switches 66 and 66a are contacted by lobes 68 and 68a on control rods-62 and 62a, placement cylinders 80 and 80a again contact a label 102, 102a for a new cycle. Fig. 11. The operation of label transferring device 2 is the same as that described above, with the exceptions that positioning cylinder 40b is always maintained in extended position, and rod 88b must be extended to bring cup 92b into contact with a new label at magazine 100b. Positioning cylinder 40b merely needs to extend in order to position placement cylinders 80b as described above. With the above label transferring device, it will be recognized that device 1 can place a label 102 in mold section 14 while platens 10 are moving from one blow molding station to another, thus greatly reducing the lag time between cycles. Since the label supply 100 is also carried on platens 10, device 1 may obtain a new label while the mold is closed and is being shifted between blow molding stations. Since the label transferring device 1 is carried on platens 10, device 1 is always maintained in registry with mold sections 14. Those skilled in the art will realize that various different types of cylinders, such as pneumatic and/or hydraulic cylinders, or positioning devices as well as different control mechanisms for activating transferring device 1 can be utilized. The label magazine may supply a continuous strip of labels which are fed in from the side of vacuum heads 92 rather than extending in a stack through the platens. Further, other securing methods could be used to secure labels 102 to transferring device 1 or to the mold once the labels have been placed within the cavity. Therefore, from the foregoing description, it will be readily appreciated by those skilled in the art that modifications and improvements may be made to the invention without departing from the concepts, disclosed herein. The scope of protection is to be determined by the claims which follow and the breadth of interpretation which the law allows. The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows.

Claims: -26- -1- A label transferring device for placing labels in a mold of a blow molding machine, the mold having separable sections carried on converging platens which are supported on a machine frame, said device comprising: a label carrying head including means for holding labels thereto and permitting selective removal of the labels from the carrying head; a reciprocating extender assembly mounted on the machine frame, said assembly including an extendable element and means for shifting said element in a straight line along a longitudinal axis only and between a withdrawn position away from the platens and an extended position between the mold sections; head placement means on said extender assembly and supporting said label carrying head for shifting said head into a mold section when said extender assembly is in said extended position; and head placement means on said extender assembly and supporting said label carrying head for shifting said head into a mold section when said extender assembly is in said extended position; and label supply means mounted on said machine frame adjacent said longitudinal axis for supplying labels to said label carrying head when said extender assembly is in said withdrawn position. -2- A label transferring device as defined by claim 1 wherein said reciprocating extender assembly includes: a piston/cylinder assembly mounted on said machine frame and having an extendable piston rod; and -27- a carriage assembly mounted on said piston rod, said head placement means being mounted on said carriage assembly. -3- A label transferring device as defined by claim 2 wherein said head placement means comprises: a placement piston/cylinder assembly secured to said carriage and having a reciprocating placement piston rod, said label carrying head being mounted on said placement piston rod. -4- A label transferring device as defined by claim 3 wherein said device further includes: another label carrying head; and another head placement means on said carriage assembly and supporting said another label carrying head for shifting said another label carrying head into the other of said mold sections when said extender assembly is in said extended position. -5- A label transferring device as defined by claim 4 wherein said device further includes another label supply means on said machine frame positioned opposite said label supply means for supplying labels to said another label carrying head. -6- A label transfering device as defined by claim 5 wherein said label carrying heads each include a holding face and a source of vacuum supplied continuously across said holding face. -7- A label transferring device as defined by claim 1 wherein said mold has a plurality of molding cavities, and said head placement means includes means for supporting and shifting a plurality of -28- said heads into each of said mold sections simultaneously. -8- A label transferring device for placing labels in a blow molding machine having separable mold sections, the machine including platens for moving the mold sections towards and away from each other, said device comprising: a fixed hydraulic cylinder rigidly mounted to said machine and having an extendable piston rod, said piston rod having a withdrawn position at which the free end of said piston rod is removed from between said separated mold sections and an extended position in which the free end of said piston rod is positioned between said mold sections; a carriage assembly mounted on the free end of said piston rod, said carriage assembly including at least one pair of hydraulic placement cylinders, each hydraulic placement cylinder having a placement piston rod and a carrying head mounted thereon, said placement cylinders disposed to extend said placement piston rods from opposite sides of said carriage assembly toward said mold sections, each of said carrying heads having holding means for securing labels to said carrying heads and for permitting the selected removal of said labels from said carrying heads; and a pair of spaced label supply magazines, said magazines disposed to be positioned on opposite sides of said carriage assembly when said piston rod is in a withdrawn position, each said label supply magazine having a label across area aligned with one of said carrying heads and spaced from said carriage assembly a distance generally equal to the distance said label placement areas are OM -29- spaced from said carriage assembly when piston rod is in an extended position. -9- In an in-mold labeling system for use with a blow molding machine, said machine including a pair of spaced, movable platens having mating mold sections mounted thereon, said platens being movable toward and away from one another to open and close said mold sections, said platens also being movable in unison between different blow molding stations within said machine, the system including means for transferring labels from a label supply exterior of said mold sections to a predetermined location within said mold sections, the improvement comprising mounting both said label supply and said transfer means on and for movement with the platen which carries the mold section to which the labels are to be transferred, whereby both said label supply and said transfer means remain in proper registry therewith. -10- The improvement as set forth in claim 9 wherein said transferring means includes a positioning member having a placement member thereon, said positioning member being shiftable between a first position wherein said placement member is in registry with said label supply and a second position wherein said placement member is in registry with said predetermined location, said placement member having a label carrying head thereon and being shiftable from a retracted position wherein said head will clear the mold section when said positioning member is shifted between said first and second positions and an extended position whereat said head contacts said -30- predetermined location within the mold section to place a label thereover. -11- The improvement as set forth in claim 10 wherein said label carrying head is a flexible cup and which further includes means for supplying vacuum pressure to said cup. * -12- The improvement as set forth in claim 11 wherein said mold has a series of vacuum ports at said predetermined area and which further includes means for supplying vacuum pressure to said ports, the pressure supplied to said ports being more negative than the pressure applied to said cup, whereby when said placement member is shifted from its extended position to its retracted position the label previously carried thereby will adhere to said preselected area without interruption of the vacuum to said cup. -13- The improvement as set forth in claim 10 wherein each of said platens has one of said transfer means and one of said label supplies mounted thereon, whereby a label can be placed in both of said mold sections. -14- The improvement as set forth in claim 10 wherein said mold sections have more than one cavity and wherein said positioning member has a number of placement members thereon corresponding to the number of said cavities. OMP

Inventors: HASL SIEGFRIED C, HASL, SIEGFRIED, C.
Applicants: HASL SIEGFRIED C, HASL, SIEGFRIED, C.
Application year: 1984
Main classification: B31B1
IPC codes: B29C49, B65C3, B65C9