LABEL MAGAZINE TRANSFER APPARATUS

Cross-Reference ■ o Related Application

This application is a Continuation-In-Par of application Serial No. ^" 594,883, filed Marcli 23, 1984, for Linear Actuator for Label Transfer Device and of application Serial No. 594,884, filed March 23, 1984, for LABEL MAGAZINE TRANSFER APPARATUS; which in turn are Continuations-ln-Part of application Serial No. 544,986, filed October 24, 1983 for IN-MOLD LABEL TRANSFER APPARATUS.

Background of the Invention

The present invention relates to apparatus for providing a supply of labels and for transferring those labels to another location. In particular, the present invention relates to a label magazine and transfer device for holding a stack of labels and for rapidly and accurately transferring the outermost label into the cavity of a blow molding machine so that the label adheres to the container during the blow molding step.

The present invention is an improvement of the inventions disclosed in applications Serial No. 594,884 and Serial No. 544,986 by the same inventors, these applications being incorpoorated herein by reference. These applications also discuss the problems and disadvantages existing in the prior art label transferring apparatuses. However, those

problems and disadvantages will be summarized herein ^" for convenience.

It is known to apply a label to a plastic container that is made by blow molding by applying the label inside the mold. Previous arrangements for supplying the labels into the mold are depicted, for example, in the Dickinson U.S. Patent No. 3,324,508, the Borkman U.S. Patent No. 3,292,209, the two U.S. Hellmer U.S. Patents Nos. 4,355,967 and 4,359,314, and the Hellmer et al Patent No. 4,397,625. These references are discussed in the Serial No. 544,986 patent application.

While the prior art does recognize the basic concept of suppyling labels at one location and transferring those labels into an open mold at another location, the devices of the prior art suffer from certain disadvantages. Generally, the aforementioned patents disclose label transferring and applying machines having complex structures that are incapable of modification so as to permit their incorporated into conventional, installed mold machinery. Furthermore, the prior art devices do not permit very rapid, yet accurate transferring and positioning of the labels.

The successful, rapid and accurate positioning of a label requires the interrelated, cooperative aspects of several components. A reliable lable supply means must be provided for accurately, rapidly supplying the labels in exactly the same position with a minimization of downtime or problems in the supplying of the labels. A transfer mechanism must have a pickup head tha positively removes the label from the label- supply means, holds the label at the - same position in the same orientation during the transfer operation, and accurately, reliably deposits the label inside the mold. In addition, the transfer

mechanism must have a reliable means for rapidly moving the transfer heads from the label supply means to the inside of the mold,, and then back to the label supply means. The problems become even more difficult when the requirement is added that the label delivery apparatus must be designed with flexibility so that .it can be incorporated into a number of different types of previously installed molding apparatuses. The requirement for component flexibility also means that the individual components must work separately and in combination in a variety of orientations and in a variety of machinery environments.

Prior arts patents like the Dickinson and Borkman patents disclose the label supplying means as being rolls of labels that are fed using conventional web-feeding apparatus. Apart from the mechanical reliability aspect, the difficulty with this type of label supply is the necessity of the additional step of cutting the labels or removing the labels from a backing, the added expense of providing rolls of labels and the machinery to feed the label rolls, the additional time needed to provide the labels, and the inaccuracy inherent in web-feeding apparatus in supplying the labels.

Thus, in order to maximize reliability and economics, label magazines rather than rolls of labels should be utilized. In addition to the Hellmer patents, the following United States patents also disclose label feeding magazines: Coates No. 1,049,996; Coates No. 1,157,660; Becker No. 1,165,936; and Balton No. 2,106,864. The Balton and Becker patents have .the disadvantage that the magazines must be oriented in a vertical direction in order to feed labels reliably to the label transfer mechanism. The magazines depicted in the Coates

patents suffer the disadvantage of being incompatible with a rapid label transferring device because of the resiliency of the magazine support in the direction of the label pile. Thus, to be compatible, the pile of labels must be rigidly supported in one direction in the magazine, yet be movable in the other direction so that a supply of labels is constantly being provided. While the Becker patent discloses a ratchet mechanism to provide the necessary rigidity, the ratchet mechanism is located at the end of a long pole which requires more space and suffers from the additional disadvantage of potential misalignments.

The critical interrelationships between the label pickup means and the label supplying means becomes even more important when high label transfer speed and accurate label positioning are required. Consistent accuracy can be achieved if the label transfer mechanism has a simplistic motion and it has to travel a minimal distance. In all of the devices of the aforementioned Dickinson, Borkman, Hellmer and Hellmer et al patents, there is a transverse component of movement between the transfer head and the label both at the moment of pickup of the label and at the moment of transfer, of the label to the mold cavity. That transverse component of motion tends to "scuff" the label as it is being transferred, thereby possibly damaging the label and certainly minimizing the ability to perfectly position the label on the label transfer head and within the mold cavity. A simple motion of the transfer head is also dictated in order to permit the retrofitting of a label transfer mechanism to installed molding machines. Therefore, accuracy and speed of label transfer are increased with an increase in the simplicity of label pickup motion and distance of travel.

A third factor which can decrease the speed and accuracy of label transfer is the design of the label pickup head. An improperly shaped pickup head can allow a label to move during the rapid transportation of the label because of either the air flow factor or the mechanical vibrations. In addition, the interface between the pickup head and the label supply means can cause either label movement or inaccurate positioning. While it is ^' known in the prior art devices to utilize a vaccum means to adhere the label to the pickup head, the design of the poickup heads has not permitted the aforementioned speed and accuracy. For example, the pickup head in the Hellmer and Hellmer et al patents- is comprised of three separate suction cups, thereby permitting significant label movement between the heads during the critical pickup and deposit steps. The pickup head in the Borkman patent, for example, is comprised of a wide rigid plate having a flat, smooth surface. While the pickup head does utilize a vacuum means to adhere temporarily the label to the pickup head, the shape and material of the pickup head contributes to the likelihood of label movement or in accurate placement during pickup or delivery. On the other hand, the pickup head depicted in the Dickinson patent does include a resilient enlarged rib located at the outermost portion of a curved head. This resilient member provides a cushioning means so that the carrier head can be brought into a close and firm contact with either a backup member or the mold. However, because the surface of the head is not smooth, .there is the probability of inaccurate label positioning and possible label slippage during the critical transfer stages.

Hence, there exists a need for further improvements in apparatus for transferring labels

frora ^' a label supply means to a mold such that the label can be accurately, yet rapidly transferred and positioned.

Summary of the Invention

It is, therefore, a purpose of the present invention to provide a new and improved label pickup and transferring apparatus which overcomes the disadvantages and limitations that have existed in the prior art.

The present invention is especially adapted for use with molding machines and is particularly usable with blow molding machines. However, it will be understood that the present invention may also be applicable to other types of molding machines such as vacuum, deep draw plastic forming machines or injection molding machines.

More specifically, the present invention is specifically adapted to being incorporated into existing molding machines which, particularly, have mold halves that move away from each other to dispose of a formed item and to receive additional material, such as a new parison, after which the mold halves move together for the subsequent molding operations. The present invention utilizes the time and spacing when the mold halves are separated from each other for placement of labels into the mold halves. The particular embodiments of the invention depicted in this application relate more principally to the storage of labels and the pickup of those labels by a transfer head in preparation for subsequent delivery of the labels into the mold halves'. However, the same motion of the apparatus for picking up a label is subsequently utilized by the apparatus for the deposition of the label into the mold halves.

The present invention incorporates the unique

requirements of the various components during their interaction for maximizing the accuracy and speed of label pickup. By properly considering the various requirements, a label transfer head can be provided with a greater amount of force when contact with a • stored label is initially made so as to minimize label movement. Once label pickup is effected, the label transfer head can be rapidly withdrawn with minimal relative movement of the label due to the configuration and composition of the label transfer head. In addition, because labels come in different sizes and shapes, the present invention permits the interchange of different label transfer heads which are better adapted for particular sized- and shaped labels.

The goals of the present invention are achieved through a number of embodiments which will be described in greater detail below. .Generally, however, all the embodiments have in common the concept of accurately positioning a label on a transfer head and rapidly moving the transfer head. This is accomplished by utilizing label transfer mechanisms which move essentially directly toward the labels or label application surfaces with a simple movement having an insigni icant or no lateral component of motion.

A first embodiment of the present invention utilizes a magazine for holding a stack of labels and a particular transfer mechanism for rapidly and repeatedly picking up one label at a time from the magazine. The magazine includes a housing for holding the stack of labels and for presenting the ^• outwardmost label at an accurately located pickup area. The magazine also comprises 'a label feeding means for resiliently urging the stack of labels toward the pickup area in a first direction and for

resisting movement of the stack in the opposite direction when the stack is contacted by the transfer mechanism. The transfer mechanism includes a transfer frame, means for moving the frame, a label transfer head or heads, and means for movabiy mounting the head or heads to the transfer frame. The mounting means provides rapid reciprocal movement of the transfer head in a direction that is perpendicular to the movement of the transfer frame such that the head is or the heads are rectilinearly moved into and out of proximity with the label.

In another embodiment of the present invention, a linear actuator for a label transfer device comprises a piston reciprocally mounted inside -a cylinder and a piston rod connected to the piston and extending out a forward end of the cylinder. The forward end of an elongate label transfer device is mounted with cantilever means to the forward piston end such that the label transfer device extends rearwardly over the cylinder forward end when the piston is at a rearward portion of the cylinder. In this embodiment of the invention, the accuracy of the positioning of an extended label transfer device is increased by shortening the stroke of the piston rod.

In a particular embodiment of the present invention, the magazine comprises a frame, at least a first pair of transversely spaced apart bars mounted to the frame and a backup plate. The bars have a plurality of ratchet teeth on the inwardly facing surfaces thereof and the edges of the backup plate are mounted in enagement with the teeth. Alternatively, the bars are smooth and the backup plate is freely movable therealong. The magazine further comprises a means for both retaining the stack of labels between the ends of the bars and the plate and for allowing removal of the outermost

label, and a spring means for urging the backup plate in the direction of the retaining means.

In another specific embodiment of the present invention, the transfer mechanism comprises a housing and a means for mounting the label transfer head on the housing. This mounting means includes a rotatable cam and a shaft having a cam follower proximal end and a distal end onto which the transfer head is mounted. A means slideably mounts the shaft to the transfer housing, and a spring means urges the shaft proximal end into contact with the cam. Alternatively, the mounting means is a double-acting pneumatic actuator. With either mounting means, the movement velocity can be controlled for two speeds of movement. Thus, the label transfer head moves slowly at a first speed into and out of engagement with the label magazine so that a single label only is repeatably picked up. Then, when the picked up label is delivered to the mold halve, the label transfer head moves quickly at the second speed to deliver the label during the short time period during which the mold halves are open.

Hence, it is an object of the present invention to provide a new and improved label transferring apparatus usable for in-mold labeling.

It is still another object of the present invention to provide a new and improved label transferring apparatus which recognizes the overall blow molding cycle and utilizes different portions of the cycle to enhance the efficiency of the label transferring apparatus.

It is still another object of the present invention to provide a new and improved mechanism for direct, rapid movement of the label transfer heads from a first position in which the label is picked up from a label storing magazine to a withdrawn position

so that the label transfer head can be moved to a further position from which, for example, the labels can be applied to the interior of a mold cavity.

It is still another object of the present invention to provide a new and improved label transferring head having a shape and composition which maximizes the adherence of a label thereto during a rapid transfer of the label.

It is still another object of the present invention to provide a new and improved mechanism for rapidly moving the label transfer head_from a first position for picking up a label to a second, withdrawn position.

It is still another object of the present invention to provide a new and improved label storing magazine in which a pile of labels can be stored and the outermost label accurately presented to the label transfer head.

These and other objects of the present invention will become apparent from the detailed description to follow, taken together with the accompanying drawings,

Brief Description of the Drawings

There follows a detailed description of preferred embodiments of the present invention which are to be read in light of accompanying drawings wherein:

Figures 1 and 1A are perspective views with parts removed for clarity illustrating alternative label transfer apparatuses including a transfer frame, a means for moving the frame between a label pickup position and a label application position, a label transfer head, and a label magazine.

Figures 2 and 2A are diagramatic, cross-sectional views of alternative transfer head positioning means.

Figure 3 is a diagramatic sketch of a second embodiment of a cam that can be used in the apparatus

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depicted in Figure 2.

Figure 4 is a perspective view of a label magazine taken from the front elevational aspect.

Figure 4A is a perspective view of an alternative label magazine taken from the rear elevation.

Figure 5 is a perspective view of the label magazine of Figure 4 taken from the rear, elevational aspect.

Figure 6 is a top plan view of the label magazine of figure 4.

Figure 7 is a front elevational view, of a label transfer head.

Figure 8 is a side cross-sectional view taken along line 8-8 of Figure 7.

Figure 9 is a horizontal cross-sectional view taken along line 9-9 of Figure 7.

Figure 10 is a front elevational view of another embodiment of a label transfer head showing a different pattern of holes and grooves.

Figure 10A is a cross-sectional view taken along line 10A-10A of Figure 10.

Figure 11 is a front elevational view of still another embodiment of a label transfer head.

Figure 12 is a front elevational view of still another embodiment of a label transfer head.

Figure 13 is a perspective, diagrammatic view illustrating yet another type of label transfer head.

Figure 14 is a partial cross-sectional view of the label transfer head depicted in Figure 2A.

Figure 15 is a side elevation view of the end of the label holding bar depicted in Figure 3.

Detailed Description of the Preferred Embodiments

There follows a detailed description of preferred embodiments of the present invention wherein like elements are represented by like numerals throughout

the several views.

Figure 1 illustrates one embodiment of a four label transfer apparatus 10 in a horizontal orientation shown at a label pickup location. The apparatus is shown with only two label magazines 12 and 14, the other two magazines together with other components being omitted for clarity. Magazines 12 and 14 are substantially identical and thus, only magazine 12 will be described hereinbelow in detail.

Label transfer apparatus 10 is also comprised of an extending mechanism 16 and a label transfer device 18 mounted on one end of mechanism 16. Extending mechanism 16 includes a double-acting air cylinder 20 having fluid lines 22 and 24 connected to opposite ends thereof. Cylinder 20 is mounted in a horizontal orientation with brackets 26 (only one of which is depicted) on a rigid base 28. A piston 30 is slidably received inside cylinder 20 and has a piston rod 32 connected thereto and extending in a longitudinal, horizontal direction outside cylinder 20. Label transfer device 18 is mounted to the distal end of piston rod 32. An arrow 34 extending in a first longitudinal, horizontal direction indicates the direction mechanism 16 can move transfer device 18. However, cylinder 20 can be mounted in any orientation thereby providing greater flexibility and maximum adaptability to installed and operating molding equipment.

Label transfer device 18 is comprised of a housing or frame 38 unto which two pairs of two opposed transfer heads 40 and 42 are mounted with rods 44 and 45 respectively. Transfer heads 40 and 42 are movable in mutually parallel directions that are perpendicular to the direction of movement of piston rod 32, which as shown by arrows 46 and 48 are in the transverse direction in Figure 1.

Transfer heads 40 and 42 each comprise a resilient pad 50 having orifices 52 therein. While pad 50 and orifices 52 are described in greater detail hereinbelow with respect to other embodiments shown in Figures 7 through 12, it will suffice here to state that pads 50 can be made of latex or silicone rubber, or any other type of soft foam rubber having closed cells that can readily compress when a vacuum is applied through orifices 52 to attach a label to the face of pad 50. Pad 50 is mounted onto a metal backing plate 54, which is turn is removably mounted onto rods 44.

Magazines 12 and 14 are shown in Figure 1 as being oriented in a vertical plane. -Ηowever, as mentioned above with respect to cylinder 20, magazines 12 and 14 are independently, rigidly mounted by means, such as mounting bar 56. Stored in magazine 12 is a stack of labels L held therein and fed thereby, as described in greater detail hereinbelow.

Although many different means may be provided for moving the transfer heads in and out, a new advantageous means is shown in Figure 2. Rotatably mounted inside frame 38 is an oblong-shaped or racetrack shaped cam 60 rigidly attached to a shaft 62. Cam 60 is rotated by any type of means, such as a power servo motor, a rotary electrical motor, a stepping motor or a rotary actuator, any one of which can be driven by pneumatics, hydraulics, electricity, solid state electronic devices or turbines.

As can be clearly seen in Figure 2, transfer heads 40 and 42, mounted on their respective rods 44 and 45, are rigidly, colinearly mounted inside frame 38. Proximal ends 64 and 65 of rods 44 and 45 engage cam 60 and ride along the outer surface thereof. Thus, proximal ends 64 and 65 serve as cam

followers. The distal ends 66 and 67 are rigidly, removably mounted onto heads 40 and 42, respectively, with means such as bolts (not shown). Rigidly mounted to respective mid portions of rods 44 and 45 are disks 68 and 69 and mounted around the disks 68 and 69 and the mid portions of rods 44 and 45 are respective cylinders 70 and 71. Coil springs 72 and 73, mounted inside cylinders 70 and 71 around rods 44 and 45, respectively, extend between removable slide bearing end plugs 74 and 75 and disks 68 and 69, respectively. Thus, rods 44 and 45 are slidably, resiliently mounted inside cylinders 70 and 71, respectively, in cam. following engagement with respective ends of cam 60. ^{_ *}

Cam 60 has a shape that provides two maximum points or lobes 76 and 77 and two minimum cam lobes 78 and 79 such that as cam 60 is rotated, rods 44 and 45 are alternately at their outermost, label pickup position (indicated by solid lines in Fig. 2) and their retracted, innermost position (indicated by dashed lines in Figure 2). As a result of the shape of cam 60, pickup heads 40 and 42 have a rapid rate of retraction.

With reference now to Fig. 3,- another cam 80 having two maximum cam lobes 82 and 83 and two minimum cam lobes 84 and 85 is depicted. Cam 80 has the advantage over cam 6,0 in that the return provided between the maximum cam lobes and minimum cam lobes is more rapid and the extension between the minimum cam lobe to the maximum cam lobe is smoother and more gradual. The surface of cam 80 in the direction of cam rotation is arcuate from minimum lobe 84 or 85, located at the minimum radial distance, to maximum lobe 82 or 83 located at the maximum radial distance. Then, cam 80 has an inward radial step 86 or 87 that provides a sudden, rapid inward movement

for rods 44 and 45. It is noted that a gradual outward movement is important so that the pickup heads can be accurately positioned against a label stored in the magazine during the label pickup step, and can be accurately positioned inside the mold half during the deposition step. On the other hand, once a label has been picked up or deposited, return movement is provided at steps 86 and 87 by cam 80. This rapid return movement permits a fast label transfer cycle.

Figure 1A illustrates a second embodiment of a four label transfer apparatus 10* in a horizontal orientation shown at a label pickup location. Label transfer apparatus 10' is shown with only two label magazines 12' and 14*, the other two magazines together with other components being omitted for clarity. Magazines 12* and 14' are substantially identical and thus only magazine 12' will be described hereinbelow in detail with respect to Figure 4A.

In a manner similar to label transfer apparatus 10, label transfer apparatus 10' is also comprised of an extending mechanism 16' and a label transfer device 18'. However, in this preferred embodiment of label transfer apparatus 10', label transfer device 18' is mounted over top of extending mechanism 16'. This is accomplished by means of a cantilever mounting plate 29* as shown. Monting plate 29' is attached to label transfer device 18' by suitable bolts 31*. Mounting plate 29' extends vertically downward to a position in front of a double-acting air cylinder 20'. Air cylinder 20' is mounted in a horizontal orientation with brackets 26' (only one of which is shown) on a rigid base 28'. A piston is slideably received inside of air cylinder 20' and has a piston rod 32* connected thereto and extending in a

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longitudinal, horizontal direction outside of cylinder 20'. The other end of piston rod 32' is attached to mounting plate 29' by nut 33'.

In order to precisely position label transfer device 18', a guide means 35" is provided. Guide means 35' includes a pair of guide rods 36* (only one of which is shown) attached to the cover of base 28' which extend parallel to piston rod 32'. Guide rods 36' are securely attached to mounting plate 29' by suitable bolts 37'. Guide rods 36' are slideably mounted in suitable guide bearings 41' (only one of which is shown) attached to the cover of base 28' in order to accurately and repeatedly control the rectilinear movement of mounting plate 29' and hence label transfer device 18'.

With the cantilever mounting of label transfer device 18' described above, label transfer apparatus 10' requires -less longitudinal space in order to be . adapted to the existing molding machine or designed into a new molding machine. In addition, with less longitudinal space required, piston rod 32' can'be shorter and thus the moment exerted by the weight of label transfer device 18' is less when piston rod 32* is fully extended. This also assists in the more accurate positioning of label transfer device 18' when piston rod 32' is fully extended.

An arrow 34* extending in a first longitudinal, horizontal direction indicates the direction extending mechanism 16' moves transfer device 18'. However, it should be appreciated that cylinder 20' can be mounted in any orientation thereby providing greater flexibility and maximum adaptability to installed and operating molding equipment.

Label transfer device 18' is comprised of a housing or shroud 38' onto which two pairs of two opposed transfer heads 40' and 42' are mounted with piston rods 44'. As shown, housing 38' also includes

an awning or overhang 39' ..which extends out over respective transfer heads 40* and 42'. By use of awning 39*, transfer heads 40' and 42' are protected from vertically falling objects. Transfer heads 40* and 42' are movable in mutually parallel directions that are perpendicular to the direction of movement of piston rod 32*, which directions are shown by arrows 46' and 48' are in the transverse direction in Figure 1A.

Transfer heads 40' and 42' each comprise a resiliently mounted bar 50* having orifices 214' therein. Bar 50' and orifices 214' are described in greater detail hereinbelow with respect to Figures 2' and 14. Bar 50' is mounted onto a metal backing plate 54' which is in turn removably mounted onto piston rods 44' .

Magazines 12' and 14' are shown in Figure 1A as being oriented in a vertical plane. However, as mentioned above with respect to cylinder 20', magazines 12' and 14* can be oriented into any appropriate plane depending upon the space availability of the molding apparatus. Magazines 12' and 14' are independently, rigidly mounted by means, such as mounting bar 56' attached to base 28'. Stored in magazine 12' is a stack of labels L held therein and fed thereby as described in greater detail hereinbelow with respect to Figure 4A.

As mentioned above, many different means can be provided for moving the transfer head in and out. A second embodiment of an advantageous feeder means is depicted in Figure 2A. Rigidly mounted inside of housing 38' is a double-acting pneumatic actuator 70' which is used for moving transfer head 40* in the direction of arrow 46' shown in Figure 1A. A similar, but oppositely directed pneumatic actuator is also provided for moving transfer head 42'.

Pneumatic actuator 70" includes a piston 68' therein to which rod 44' is attached. The opposite end of rod 44' is attached to metal backing plate 54'by means of bolts 49' which are received on the threaded end of rod 44' as shown. Fluid lines 72' and 73 ^r are selectively actuated as explained below to move piston 68' inside of cylinder 75' and to thereby move rod 44' into and out of cylinder 70'. As this occurs, transfer head 40' is moved away from frame 38' out from under awning 39', and then back.

In this preferred embodiment, fJuid lines 72' and 73' are suitably coupled to a variable source of pressure. This is accomplished by solenoid operated shut-off valves 76" and 77' in respective lines 72' and 73* before these lines combine into a common line 78' in which a solenoid operated throttle valve 79' is provided. Thus, in one mode of operation, where throttle valve 79' is actuated, feed lines 72' and 73' are selectively pressurized by valves 76' and 77' with a first low pressure. This causes transfer head 40' to move slowly out and then slowly back. This slow motion of transfer head 40' is used when ^' transfer head 40' picks up a label r, from the adjacent magazine. By use of this _.Iow motion, the withdrawal of only a single label L from the magazine is more uniformly achieved. In the other mode of operation, where fluid lines 72' and 73' are connected to a high source of pressure by opening throttle valve 79' completely, transfer head 40' moves rapidly away and back relative to frame 38*. This mode of operation is used to transfer the label L attached to transfer head 40' to the adjacent mold half. During this operation, the quickness of the operation is important as the mold halves remain apart for only a limited period of time.

Although many different magazine structures can

be used with the ohter features described in the application, one new and improved magazine 12 will be described in detail below with reference to Figures 4, 5 and 6. Magazine 12 comprises a sturdy, rigid metal bar frame 100 that has a generally rectangular shape. The shape of frame 100 provides for greater flexibility in orientation and location. Frame 100 can be rigidly, directly, and vertically mounted onto a horizontal platform 102 (as shown in Fig. 4), or frame 100 can be attached to the ends of two mounting pegs 104 which in turn are mounted onto a platform 103 (as shown in Fig. 5). In addition, as will be appreciated from Figure 1, the frame of magazine 12 can be rigidly attached to the frame -of- magazine 14.

Mounted onto magazine frame 100 is a label feeding means 101 that positively supplies labels L so that the outermost label is always in approximately the same position, on the one hand, and yet the label is rigidly held at that position when pickup head 40 or 42 comes into contact therewith. Label feeding means 101 is comprised of two pairs of two spaced apart bars 106 and 108, each bar 106 and 108 having a plurality of ratchet teeth 110 mounted on the inwardly facing surfaces thereof. Bars 106 and 108 are 'mounted to individual mounting blocks 112 which in turn, are removably, rigidly mounted onto frame 100 with screws 114. Mounting block 112 can be mounted with any one of a plurality of holes 116 provided in frame 100 along the periphery thereof. In this way, different shaped and sized labels can be accommodated with a single size magazine frame 100. Label feeding means 101 further includes a flexible label backing plate or pad 118 which is preferably made of a rigid plastic material so that labels L will not be cut or ratchet teeth 110 worn too quickly. Plate 118 is preferably curved and is

relatively thin at the transverse edges so that these edges can be engaged by ratchet teeth 110. Bars 106 and 108 with their ratchet teeth 110 and plate 118 together comprise a ratchet mechanism for feeding labels to a ^' label supply location.

Rigidly mounted to the end of each bar 106 and 108 of magazine 12 is a retaining finger 120 that has an inwardly projecting tip 122. Finger 120 is rigidly mounted to the end of the respective bar 106 or 108 by means such as being welded or attached with screws. Tip 122 preferably has an inclined surface with an angle that will retain the outermost label, on the one hand, yet will release it to a transfer head, on the other hand. Mounted to the bottom of frame 100 are a pair of support members 124. Support members 124 preferably have a smooth upper suface and are for supporting the bottom of labels L while still permitting the labels L to be slid therealong.

Label backing plate 118 is resiliently urged in a foward outward direction by a spring means comprised of a pivotally mounted arm 126 having a bend therein at 128, and a coil spring 130 mounted between the bottom surface of the top of frame 100 and a point near bend 128. Arm 126 is mounted at its upper end with a pivot pin 132 to a mounting block 134, which in turn is rigidly mounted with means, such as a screw 136 to the top of frame 100. The other end of spring arm 126 engages the back of plate 118 preferably, by means which reduce friction and permit plate 118 to move linearly while arm 126 is moving arcuately. For example, a roller on the end of arm 126 can roll against plate 118. Alternatively, the end of 126 can have a low friction material block attached thereto, as shown at 118a in Figure 6, for example Teflon, mounted thereon to engage plate 118.

Depicted in Figure 4A is an alternative

embodiment of a magazine 12' as viewed from the rear. Magazine 12' is broadly similar to magazine 12 described above. However, magazine 12' is designed to more regularly deliver only a single label to the appropriate transfer head and to alleviate the problem of nicking labels which sometimes occurred with magazine 12. As shown, magazine 12' comprises a sturdy and rigid metal bar frame 100' that has a generally rectangular shape. Frame 100' is preferably rigidly and vertically mounted by bolts 104' onto horizontal platform 102' which is supported by mounting bar 56'.

Mounted onto magazine frame 100' is a label feeding means 101' that positively supplies labels L so that the outermost label is always in approximately the same position and yet the label is rigidly held at that position when pickup head 40' or 42' comes into contact therewith. Label feeding means 101' is comprised of two pairs of spaced apart bars 106* and 108'. Each bar 106' and 108' is rounded along the label engaging portion so as to pcovide a smooth sliding surface along which labels L move. Bars 106' and 108' are mounted to frame 100' by means of threaded rods 114' which are received in a flat portion of bars 106' and 108' opposite the rounded portion contacting labels L. Threaded rods 114' also pass through mounting blocks 112' extending from frame 100'. Suitable nuts 110* which are threadably received on threaded rods 114' and which are located on either side of mounting blocks 112' are used to precisely position threaded rods 114' such that bars 106' and 108' engage the stack of labels L. Mounted to the bottom of frame 100' by mounting blocks 121' are a pair of support members 124'. Support members 124' also preferably have a smooth upper surface and are used for supporting the bottom of labels L while still allowing the labels L

to slide freely therealong. In this manner, different shapes and sized labels can be accommodated with a single sized magazine frame 100'.

Label feeding means 101* also includes a backing plate 118' which has the same silhouette as labels L. Backing plate 118* is resiliently urged in a forward and outward direction by a flat bar 119'. As shown in Figure 4A, flat bar 119* is mounted for rectilinear movement by means of rods 126' which extend from mounting brackets 128' attached to frame 100*. Located around rods 126' between _^ flat bar 119' and the associated mounting bracket 128* is a compressed spring 130'. Springs 130' resiliently urge flat bar 119' and hence labels L in the forward direction in a smooth and continuous manner.

Rigidly mounted to the end of each bar 106' or 108' of magazine 12' is a retaining finger 120' that has an inwardly projecting tip 122' as shown in Figure 15 with respect to bar 106'. Although finger 120' appears similar to finger 120 described above, there is a marked difference. With finger 120', a continuously curved concave surface 123' is provided between tip 122' and the end of bar 106'. Concave surface 123* serves to retain the outermost label until a transfer head positively pulls the outermost label away from the stack of labels L in the manner similar to the operation of finger 120. However, concave surface 122' also serves to cause the outermost label to bow outward slightly, separating the outermost label from the rest of the stack so that the appropriate transfer head more easily withdraws the single outermost label each time. In addition, the continuous curve of concave surface 123* eliminates the nicking of the outermost label which occurred with the inclined surface of tip 120

described above.

For convenience, it is preferred that a plurality of frames 100' be provided with each label transfer apparatus 10'. ^' Then, each frame 100' is suitably adjusted for receiving a specified label. Then, whenever it is necessary to change from one label to another label in label transfer apparatus 10', frame 100' containing the old labels is simply removed from platform 102' by loosening bolts 104' and a new frame 100' containing the appropriate labels substitued therefor. This provides for a quick and easy change of labels without having to adjust bars 106' and 108* for each configuration of label.

With respect to Figs. 7, 8 and 9,_a. further embodiment of a transfer head 140 is depicted. Transfer head 140 is comprised of a pad, the outer contour of which is shaped to mate with the shape of the label being transferred. Of course each head is removable so that a specific head can be provided for each size label being transferred. For ^■ convenience, there is shown herein a generally rectangular pad 142. The pad is made of a soft, silicone rubber having closed cells so as to be easily conformable with the contour of a surface against which it is pressed. Pad 142 has a front surface 144, a back surface 146, a top 148 and a bottom 150. In fact, preferably the width of pad top 148 is slightly smaller than the width of pad bottom 150. Front pad surface 144 has a convex shape that is contoured to the shape of the mold interior. As seen in Fig. 8, pad top 148 is also thinner in cross-sectional thickness than pad bottom 150. Again, this overall configuration depends upon the particular labels being applied and the mold interior.

Securely mounted to the back surface 146 of pad 142 is a metal backing plate 154 that is provided

with a central orifice or vacuum port 156. Vacuum port 156 can be threaded or otherwise adapted to be attachable to a vacuum supply line (not shown). Back surface 146 of pad 142 is provided with a channel or recess 158 running along the interior length thereof and centrally located with respect to the sides thereof. A plurality of orifices 160 extend completely through pad 142 and are in communication with recess 158. Thus, recess -158 acts as a vacuum plenum between vacuum port 156 and orifices 160. The periphery of pad 142 is sealingly attached or mounted onto backing plate 154 so that a vacuum is applied only through orifices 160.

In the subsequent discussion and _in Figure 7 through 12 there are described many different paterns of holes and passageways for the flow of air into the interior of the pad. It will be understood that after a given contour pad has been selected, so as to match the label being transferred, one would select from the different arrangements of ^" air flow channels and holes which will give the best results for that particular pad contour.

Front surface 144 of pad 140 has two grooves 162 and 164 emanating from and in communication with each orifice 160. In the embodiment shown in Figure 7, grooves 162 and 164 have an overall chevron or inverted "V" shape. However, grooves 162 and 164 in a further embodiment could have an overall "V" shape. Grooves 162 and 164 have the greatest cross-sectional area closest to orifice 160 which gradually decreases or tapers to the respective ends thereof. The cross-sectional area changes can be accomplished by grooves 162 and 164 becoming shallower along the lengths thereof, by the width of grooves 162 and 164 becoming narrower along the lengths thereof, or by some combination of the two.

The overall shape of grooves 162 and 164 provide an air foil effect when a label L is in contact with or about to contact pad front surface 144. Because the air flow velocity will be faster at the end portions of grooves 162 and 164, a greater downward acting differential pressure will result and the ends of the label L will be pulled down first. This action will not only ensure that labels L will be firmly attached to pad 142, but also that they will be accurately positioned thereon with limited tendency to slide.

Figures 10, 11, and 12 depict three alternative embodiments of transfer head pads 242, 342, and 442. With particular reference to Figure 10, the front surface 244 of pad 242 is provided with two rows of orifices 260 and 261. A plurality of ^~ grooves 262 and 264 in a cross-hatched pattern interconnect each one of orifices 260 and 261.

Figure 10A illustrates the funnel, "trumpet" shape of two of the holes. This also illustrates the shallow channel 262, 264 running between these two . holes.

With respect to transfer head pad 342 in fig. 11, only two orifices 360 and 361 are provided. However, two sets of four grooves 362 and 364 respectively emanate radially outwardly from orifices 360 and 361 so as to provide a star-shaped pattern. Each one of the four grooves 362 and 364 has the aforementioned tapered cross-sectional area along the lengths thereof as described above with respect to grooves 262 and 264 in Figure 7.

With reference now to Figure 12, transfer head pad 442 is provided on the front surface 444 thereof an array of three rows of orifices 460, 461, and 461a, each row having two orifices therein. Interconnecting each row of orifices is a corresponding longitudinally aligned groove 362, 364

and 366. The ends of grooves 362, 364 and 366 also have a tapered cross-sectional area.

While five different orifice and groove arrangements have been shown on the front surfaces of the transfer head pads in the embodiment of Figs. 1, 7, 10, 11 and 12, other arrangements can be utilized. The particular arrangement selected depends upon the overall dimensions, configuration, weight and thickness of the labels to be transferred.

In all of the illustrated embodiments in Figures 7 through 12, the individual holes preferably have the shape as illustrtated in Figure 9 which is "trumpet" shaped including a circular outer funnel and an inner smaller circular passageway. The channels on the surface of the pad are relatively shallow and uniform where they extend between holes at each end thereto as in Figures 10 and 10A. However, where the channels extend from a hole to a free end as in Figures 7 through 9, 11 and 12, the channels are of gradually reduced cross section as they progress from the hole to the free end. Tnat is, as shown in Figure 9, the channels are of a decreasing depth and as shown in Figure 7 the channels are of decreasing cross section when viewed in plan. The effect of these features is to increase the air flow velocity closer to the holes and then down into the holes, and this has a highly advantageous effect in holding a label onto the pad.

With reference now to Fig. 13, yet another transfer head 540 is depicted. Head 540, unlike the aforedescribed transfer heads, is comprised of a rigid plastic or rubber pad 542 mounted onto a backing plate 554. A plurality of orifices 560 are aligned in a row and extend through pad 542 to a plenum (not shown) located between the back surface of pad 542 and backing plate 554. A vacuum tube 570

is connected to the rear of backing plate 554 and communicates through an orifice therein with the aforementioned plenum.

It has been found that head 540 is effective for transferring a labeT L that has a length greater than the width of pad 542 so that the edges of label L can curl around pad 542. Preferably, label L is relatively thin and flexible and thus has a very light weight.

With reference to Figure 2A, another preferred transfer head 40' is depicted for use with label transfer apparatus 10'. As mentioned above, transfer head 40' includes a bar 50' which is mounted to a metal backing plate 54'. Bar 50' is attached to backing plate 54'. Bar 50' is attached to backing plate 54' by a pivot means 200' and a resilient means 202'. Pivot means 200* includes a pivot bar 204' which is securely attached to backing plate 54', as by welding. At the other end of pivot bar 204', pivot bar 204' is attached to bar 50' by a suitable bolt 206' or the like so that bolt 206' forms a pivot axis about which bar 50' pivots relative to backing plate 54*. It should be appreciated that pivot means 200' also includes a similar pivot bar and coaxial bolt on the opposite side of transfer head 40'.

Resilient means 202' comprises a single bolt 208* extending through both bar 50* and metal backing plate 54*. Bar 208' has stops 210' at respective ends and a spring 212' located about bolt 208' in the location between bar 50' and metal backing plate 54'. With this construction, spring 212' urges bar 50* away from backing plate 54' about the pivot axis formed by bolt 206'.

In this embodiment of transfer head 40', only two vertically spaced orifices 214* are provided. As

'

shown in greater detail in Figure 14, orifice 214' is formed by a cylindrical recess 216' provided in the front face of bar 50'. Recess 216' is fluidly connected with a passage 218' in suitable communication with a source of vacuum. Provided in cylindrical recess 216' is a resilient O-ring 220'. As shown, O-ring 220' extends forward of the front face of bar 50' so as to present a resilient orifice 214' when transfer head 40' is actuated. Preferably, from 1/2 to 1/3 of the thickness of O-ring 220* extends beyond the face of bar 50'. In operation, transfer head 40' provides a simple and efficient means for removing a single label from magazine 12' and for then depositing the label in J_he appropriate mold half. As transfer head 40' is actuated outwards to engage labels L or a mold half, the surface opposing the outward extension of transfer head 40, is resiliently engaged by two means. In the first instance, spring 218' of resilient means 202' acts to absorb any large forces exerted by the opposing surface. Next, O-rings 220' also serve to absorb any opposing force. With this combination, a repeatable single delivery of a label L is achieved.

Returning now to fig. 1, the operation of label transfer apparatus 10 will now be described in general terms. Label transfer device 18 is initially positioned by cylinder 20 in the retracted condition so that heads 40 and 42 are in transverse alignment with magazines 12 and 14. Cam 60 (Fig. 2) or cam 80 (Fig. 3) is activated causing rods 44 and 45 to be resiliently extended outwardly in the transverse direction, which is perpendicular to the direction of movement of transfer device 18. At the same time, a vacuum is applied to heads 40 and 42 as the heads move transversely outwardly and into engagement with the outermost label L. As soon as contact is made.

further outward movement of heads 40 and 42 is resisted as a result of the ratchet machanism of . magazines 12 and 14. This provides a firm contact between the outer suface of heads 40 and 42 and the outermost label L. As cam 60 (or 80) continues to turn, springs 72 and 74 will rapidly return heads 40 and 42 to their respective withdrawn positions, taking with them the corresponding labels now securely attached to the outer surfaces of the heads. Air is then emitted through fluid line 24 to cause piston 30 to move in the forward longitudinal direction-, thereby positioning transfer device 18 to a location facing the molds into which the labels L are to be transferred. While device 18 is being positioned, cam 60 (or 80) continues to rotate and the heads 40 and 42 begin to move in the transverse outwardly directions. With proper timing and transverse distances properly selected, the transfer device will enter the mold area at exactly the correct time as transfer heads 40 and 42 are being moved in the outward direction so as to minimize the amount of time that device 18 is between the two mold halves. hen transfer heads 40 and 42 have been extended to their full outward position, they will be in contact with the inner suface of the mold halves. At that time, the vacuum being supplied to heads 40 and 42 is terminated and vacuum is applied to the mold halves so as to retain the labels therein. Cam 60 continues to turn and with proper timing, after the label transfer, pickup heads 40 and 42 are again rapidly withdrawn. Simultaneously, pressurized air is admitted to fluid line 22 while fluid line 24 is vented. This causes piston 30 to be driven in the rearward direction and transfer device 18 to be again positioned in front of magazine 12 and 14. The mold

halves can then be closed and the molding process begun.

Transfer apparatus 10' operates in a manner similar to transfer apparatus 10 described above. However, it should be appreciated that awnings 39' protect transfer heads 40' and 42' during movement frame 38' . . In addition, the configuration of transfer heads 40' and 42* and of magazines 12' and 14* provide an especially efficient and reliable label transfer apparatus 10'. As mentioned above, the control of the velocity of tranfer heads 40' and 42' so that this velocity is relatively slow adjacent magazine 12' and 14' and relatively quick adjacent the respective mold half also contributes to the efficient and reliable operation of label transfer apparatus 10' .

It will be understood that these improvements in label transfer heads are applicable to any of the label transfer apparatuses described in the prior applications.

The operation of the various ^* embodiments have either been discussed during the description of the respective embodiments or will be apparaent therefrom.

Although the invention has been described with respect to specific embodiments, it will be apparent that the invention is capable of numerous modifications and variations without departing from the spirit and scope of the invention.