Anti-rotation wear plate for capping machine

A bottle support structure and wear plate for use in a rotary capping machine used to apply caps onto the upper threaded neck of a series of plastic containers. The plastic containers have a generally cylindrical body with an outer cylindrical periphery with a diameter and a pedaloid base with spaced pads separated by radial recesses extending from a center recess. The bottle support structure supports the weight of the bottle as the bottle is being capped be prevent the body and base of the bottle from being deformed or crushed during the capping process. The wear plate is a flat ring rotated in unison with a star wheel about a machine axis. The ring has an upwardly facing flat surface and a series of container receiving nests movable in the circular path as the ring is rotated. Each of the nests has at least one elongated bar-like abutment projecting upwardly from the flat surface a given vertical distance. The one or more abutments prevent the bottle from rotating during the capping process.

The present invention relates to the art of capping bottles or containers as they are moved along a preselected path and more particularly to a bottle support system and a wear plate in a capping machine which supports the bottle and prevents rotation of the while a cap is being tightened onto the neck of the bottle.

The invention is particularly applicable to assembly of a cap onto a plastic bottle of the type having a pedaloid base constituting a plurality of protruding pads separated by diverging recesses or crevices. However the invention has much broader applications and can be used in applying a cap onto a bottle which has various protrusions on its base.

INCORPORATION BY REFERENCE

Peronek U.S. Pat. No. 4,939,890; Martin U.S. Pat. No. 5,826,400 and Peronek U.S. Pat. No. 5,934,042 describe capping machines of the type to which the present invention is directed, together with a description of several arrangements used in the art for preventing rotation of the bottle as it is being capped during its rotary movement by a star wheel. These patents are incorporated by reference herein as background information to explain certain prior anti-rotation arrangements of which the present invention is a specific improvement. Consequently, the details of the capping machine of the type to which the present invention is directed need not be explained.

BACKGROUND OF THE INVENTION

A capping machine or conventional capping apparatus includes a star wheel rotatable about a machine axis and having a plurality of outwardly opening pockets adapted to receive bottles fed in an assembly line fashion to the star wheel. Overlying the rotating star wheel is a plurality of individual capper heads for use in applying a cap to the upper threaded neck of a plastic bottle carried by the star wheel in an arcuate or circular path centered about the machine axis. A turret rotates the star wheel and capping heads in synchronism about the machine axis with an individual capping head located directly above each bottle receiving pocket on the star wheel. The capper heads employ a clutch mechanism whereby the head carrying a cap is rotated and driven axially downwardly at a predetermined force and torque limiting value to tighten the cap onto the bottle neck.

In accordance with standard practice, an entrant guide mechanism or conveyor is mated with the capper star wheel to feed filled bottles to an entry point on or at the end of the path of movement of the capper star wheel. An exit guide mechanism or conveyor is similarly mated to the capper star wheel to transfer the capped bottles from an exit point on or at the end of the rotating capper star wheel. A stationary rear guide plate extends generally between the entry and exit points on the capping machine and is spaced radially outwardly from the pockets of the star wheel and functions to retain the bottles in the pockets as the star wheel rotates in unison with the capping heads. Below the bottles or containers is a segmented ring, known as a wear plate, rotated with the star wheel onto which the bottles or containers rest during capping. This is a conventional capping machine employed in bottling plants and is the mechanism to which the present invention is directed.

During the capping operation, it is necessary to assure that the bottle does not spin as the cap is tightened. A spinning action during the capping procedure can cause damage to the plastic container and reduce the desired tightness of the cap being applied automatically to the bottle as it is translated in a path determined by the star wheel. In the past, certain cap designs required a relatively high downward force during the capping operation. When this occurs, spinning of the bottle is prevented by frictional contact with the pocket, with the rear guide plate or with both of these structures. As the downward force during the capping operation has been reduced due to the design and functional characteristics of the cap being applied, friction at the neck of the bottles has been increased either by the use of upwardly directed knife ridges provided in the anti-spin segment on the top of the individual star wheel pockets. This structure is disclosed in Peronek U.S. Pat. No. 4,939,890. The knife ridges on the anti-spin segment on each pocket engage the lower surface of a circular flange at the bottom of the threaded neck of a plastic bottle to prevent rotation of the plastic bottle. The use of knife ridges to prevent bottle rotation is more effective than using a downward force on the bottle. For that reason, the anti-rotation or anti-spin device of Peronek U.S. Pat. No. 4,939,890 has become the standard in the trade to prevent rotation of plastic bottles as they are being capped with relatively low downward force. Peronek U.S. Pat. No. 4,939,890 teaches a mechanism for externally applying a downward force on the body of a bottle being capped, which force is independent of the downward force created by the capping operation. This anti-spin or anti-rotation mechanism has been successful; however, it requires a mechanism for exerting a downward force on the bottle which is expensive and is dependent upon certain structural characteristics at the upper portion of the bottle itself. Changes in bottle configuration often require a new force exerting mechanism.

The anti-rotation device of Peronek U.S. Pat. No. 4,939,890 is a successful arrangement for applying plastic threaded safety caps onto the top of plastic bottles where the caps do not require heat to set or position the lower lock band around the neck of the bottle. The lock band of the cap simply snaps into a locking position when the capping head threads the cap onto the upper threaded neck of the plastic bottle. In this type of capping operation, the capper head exerts a downward force of between 15–20 pounds. This low axial force makes retention of the bottle from rotation within the star wheel pocket very difficult. This situation motivated the development and use of the anti-rotation feature disclosed and claimed in Peronek U.S. Pat. No. 4,939,890. Although Peronek U.S. Pat. No. 4,939,890 successfully prevents bottle rotation during the capping process, the knife ridges leaves a mark on the lower lip of the plastic bottle. In addition, the knife ridges causes small amounts of plastic to be scratched off the bottle. Over time, these plastic scraps accumulate and must be removed from the bottle capping machine, thus resulting is down time for the machine.

An alternative bottle capping arrangement is disclosed in Martin U.S. Pat. No. 5,826,400 and sold by AMCO Products Company under the trademark PETA DRIVE. In this device, plastic bottles with pedaloid bases are capped in a standard machine with a lower plate rotated with the capping heads. The lower plate includes nests having recessed bottle supporting surfaces, which nests are directly aligned with the capping heads and pockets of the rotating star wheel. In this device, a plurality of specially contoured recesses that match the pedaloid base configuration are used to receive and support the bases of the bottles as the bottles are moved by the star wheel. Since the bottles rest upon the recessed bottle supporting surfaces and are held within the nest on the plate, rotation of the bottles is prevented by an interference between the fingers in the nest and the bottom, or base, of the bottle. This bottle capping arrangement, does not use knife ridges to prevent bottle rotation during the capping operation. However, the provision of a lower circular wear plate with machined recesses, each matching the contour of a pedaloid base of the plastic bottles, is quite expensive. Each of the contoured recesses must be specially produced and accurately matched with respect to the actual shape of each pedaloid base of the bottle being processed. Consequently, each bottle requires its own lower support wear plate. Indeed, when the filled bottles being capped are changed from a four pad pedaloid base to a five pad pedaloid base, a completely new, specially machined plate for supporting the pedaloid bases must be assembled onto the machine. This arrangement for providing a plate rotatable with the star wheel for supporting the lower pedaloid bases of the bottles demands a plate which must be accurately machined for use with specific star wheels.

Another anti-rotation system includes arrangement for fixing the support member or wear plate in a position spaced from the turret where the containers are supported by the rib and slide along a rib as the container is moved around the arcuate path dictated by the movement of capping head and the star wheel. The rib extends into the lower recess of the pedaloid base of the individual bottle to prevent rotation of the bottle or container as the capping head drives the cap downwardly onto the upper threaded neck of the bottle. By using this construction, a lower support plate carrying the upstanding rib is fixed and does not rotate with the star wheel. This use of a fixed rib constitutes an improvement over other arrangements for using a lower plate with specially contoured recesses to provide interference against rotation of the bottle by the capping head; however, it requires a significant modification of the capping machine. Furthermore, the position of the rib relative to the start wheel must be adjusted for different number pedaloid bases. The repositioning requires the exchanging of one rib with another rib having a different curvature. This involves expensive retrofitting.

Still another anti-rotation system is disclosed in Peronek U.S. Pat. No. 5,934,042. In this system, plastic bottles with pedaloid bases are capped in a standard machine with a lower wear plate rotated with the capping heads. The wear plate includes nests that have bar-like abutments that are positioned on the surface of the wear plate. During the capping operation, the base of the bottle is lowered onto the bar-like abutments. These bar-like abutments engage the bottom surfaces of the pedaloid base to prevent the bottle from rotating during the capping operation. The bar-like abutments are designed to be removable and adjustable so as to accommodate different sizes and types of bottles. This bottle capping device is a significant improvement over prior bottle capping arrangements in that there is very little cost associated with adjusting the bar-like abutments on the wear plate to accommodate different types of bottles to be capped. In addition, Peronek U.S. Pat. No. 5,934,042 discloses an anti-rotation mechanism to be used on a capping machine which does not rely upon developing large downward frictional forces on the top of the bottle during the capping operation.

Although Peronek U.S. Pat. No. 5,934,042 is a significant improvement over prior bottle capping arrangements, bottles that are capped by the bottle capping device of Peronek U.S. Pat. No. 5,934,042 may be deformed or crushed during the capping process. This deformation or crushing problem primarily exists when capping plastic bottles. Prior to a plastic bottle being capped, the bottle is filled with a liquid. Commonly, the bottle is filled with a heated liquid prior to being capped. The heated liquid in the plastic bottle tends to soften the plastic bottle thereby making the bottle susceptible to deformation. During the capping operation, the capper heads are lowered onto the neck of the bottle apply a downward force while screwing a cap onto the neck of the bottle. Due to the softened state of the plastic bottle, this downward force can cause the body and/or base of the plastic bottle to deform or be crushed during the capping operation.

The incidents of deformation or crushing are especially evident when using the bottle capping machine of Martin U.S. Pat. No. 5,826,400 and in bottle capping machines wherein a large downward force is used to prevent the bottle from rotating. In the bottle capping machine of Martin '400, the base of the bottle rests upon a bottle supporting surface. As a result, when a downward force is applied to the softened plastic bottle, the body and/or base tends to deform or crush since the base of the bottle cannot move downwardly. The incidence of deformation or crushing when using the bottle capping machine of Peronek U.S. Pat. No. 5,934,042 is much less than in Martin U.S. Pat. No. 5,826,400 since the base of the plastic bottle rests on the bar-like abutments and not the top surface of the wear plate. As a result, the base of the bottle can move downwardly some small distance when the cap is applied to the bottle thereby significantly reducing the incidence of deformation or crushing of the body and/or base of the bottle during the capping process.

In view of the existing art of capping plastic bottles, there is a need for a bottle capping device than can prevent the bottle from rotating during the capping process without causing the bottle to be deformed or crushed.

SUMMARY OF THE INVENTION

In accordance with the present invention, there is provided a device or method for preventing rotation of a container or bottle of the type having a generally cylindrical body. The invention is particularly applicable for use with a bottle having a pedaloid base, which is somewhat standard in the soft drink industry. These bases include a plurality of downwardly extending pads, generally four or five pads, separated by diverging recesses. The bottle can be made of glass, metal paper and/or plastic. The invention is particularly directed to plastic bottles which can be deformed when heated and/or when heated fluids are filled into the bottle. The device or method for capping the bottle reduces the compressive forces applied to the body and between the top and base of a bottle during the capping process thereby reducing or eliminating the deformation or crushing of the bottle during the capping process.

In accordance with the primary aspect of the present invention, there is provided a bottle neck supporting structure to support all or part of the weight of the bottle during the capping process, and a wear plate having one or more abutments to interfere with the rotation of the bottle during the capping process. The inventor developed and successfully tested the use of the bottle neck supporting structure in the marketplace less than one year prior to filing this application. The inventor has become aware that AMCO Products Company subsequently modified its PETA DRIVE bottle capping machine to include a structure about the neck of the bottle. In one embodiment of the present invention, the capping machine is adapted to accommodate bottles or containers having a pedaloid base. In one specific aspect of this embodiment, the pedaloid base has spaced pads separated by radial recesses extending from a center recess of the base. In another specific aspect of the embodiment, the bottle has an outer cylindrical periphery. In still another embodiment, the bottle is substantially formed of a plastic material. In yet another embodiment, the bottle capping machine s a rotary capping machine having a rotating star wheel of the type disclosed in Peronek U.S. Pat. No. 5,934,042. In this embodiment, the capping machine moves the bottles or containers along a circular path by a star wheel that has outwardly protruding pockets supporting the bottles or containers about the wear plate. In a further embodiment, the wear plate is a flat ring that rotates in unison with the star wheel about the machine axis so that the containers move along a given circular path. In one specific aspect of this embodiment, the wear plate has an upwardly facing flat surface with one or more bottle or container receiving nests movable along the circular path as the ring is rotated by the turret of the capping machine. Each of these nests has an inner area constituting a flat surface and at least one abutment projecting upwardly from the flat surface a given vertical distance and extending in a direction radial of the inner area of the nest. This nest is one form of the nest that can be used. Another type of nest is disclosed in Martin U.S. Pat. No. 5,826,400 which is incorporated herein by reference. The nest disclosed in Martin has a bottle supporting surface with fingers or abutments extending upwardly therefrom and which bottle supporting surface is designed to support the base of a bottle. In addition, the bottle supporting surface is recessed from the top surface of the wear plate. Both the nest arrangement specifically illustrated in this invention and the nest arrangement disclosed in Martin U.S. Pat. No. 5,826,400 can be used in the present invention. In still a further embodiment, the each nest of the wear plate includes two or more of the abutments that project radially outwardly from the inner area defining the nest. In one specific aspect of this embodiment, the radially projecting abutments are spaced by an angle defined as 360°/X, wherein X is a number of pads in the pedaloid base. The typical container to which the invention is specifically directed has five pads; therefore, the abutments are spaced at one or more 72° intervals. Consequently, a nest containing five abutments, each abutment is spaced at a 72° interval from an adjacent abutment. For a nest containing four abutments, the abutments are spaced at a 72° interval from an adjacent abutment with the exception that two adjacent abutments are spaced at a 144° interval from one another. As can be appreciated many other interval combinations can be used when two or three abutments are used.

In accordance with another aspect of the invention, the bottle capping machine includes a bottle support that at least supports all or part of the weight of the bottle or container at or about the neck of the bottle or container during the capping process. During the capping process, at least about 5 lbs. of downward force are applied to the bottle or container during the capping process. This downward force can cause one or more bottles or containers during the capping process to be deformed, crushed or otherwise damaged during the capping process. The present invention overcomes this problem by supporting all or part of the weight of the bottle or container at or about the neck of the bottle or container during the capping process. By supporting the bottle or container at the neck, the bottle support partially or totally counters the downward forced applied to the top of the bottle during capping, thus amount of downward force applied to the body and/or base of the bottle or container is significantly reduced or eliminated, thereby significantly reducing or eliminating the occurrences of deformation or crushing of the bottle or container during the capping process. When the bottle is fully supported by the bottle support during the capping process, the base of the bottle does not rest upon the wear plate or structures in or on the wear plate. As can be appreciated in this arrangement, when the wear plate or structures on or in the wear plate are used to inhibit rotation of the bottle or container during the capping process, the base of the bottle or container will encounter such structures. However, the contact between these structures and the base involves minimal support of the bottle or container along the vertical axis of the bottle or container, thus bottle or container is still considered to be fully supported by the bottle support during the capping process. As can also be appreciated, when the base of the bottle is spaced a very small distance from the wear plate or structures on or in the wear plate, prior to the capping process, the bottle is considered to be fully supported by the bottle support. However, during the capping process, the downward force applied to the top of the bottle or container can cause slight deflection of the bottle support components and/or the surface of the bottle or container where the bottle support contact the bottle or container thereby resulting in the base of the bottle or container moving into contact with the wear plate or structures on or in the wear plate. Although the base of the bottle or container contact the wear plate or structures on or in the wear plate during the capping process, much of the downward force is countered by the bottle support thus reducing or eliminating the occurrences of deformation or crushing of the bottle or container during the capping process. In one embodiment, the weight of the bottle or container is fully supported at or about the neck of the bottle or container during the capping process. In one specific aspect of this embodiment, the bottle or container is fully supported at the neck of the bottle or container during the capping process. In another specific aspect of this embodiment, the bottle or container includes a flange at the neck of the bottle or container. The bottle support engages the bottom of the flange to partially or fully support the weight of the bottle or container of the flange. In yet another embodiment, the base of the bottle or container is suspended above the one or more abutments during the capping process. In still yet another embodiment, the base of the bottle or container is supported above the wear plate during the capping process. In one specific aspect of this embodiment, the bottom of the bottle or container is supported above the wear plate a sufficient height such that the bottom of the bottle or container does not contact the one or more abutments on the wear plate. In this aspect of the embodiment, the base of the bottle or container includes pedaloid base that has spaced pads separated by radial recesses extending from a center of the base. During the capping process, the bottom of the bottle or container is suspended above the wear plate such that the one or more abutments when positioned in the radial recesses, the surfaces of the radial recesses are spaced between the about 0.0001–0.5 inch above the one or more abutments. Although the one or more abutments do not contact the radial recesses, the one or more abutments still prevent the bottle or container from rotating during the capping process since the one or abutments do not allow the pads of the pedaloid base to pass over the one or more abutments. In another specific aspect of this embodiment, the base of the bottle does not contact the wear plate or structures on or in the wear plate just prior to the downward force being applied by the capping process, and the base of the bottle or container is caused to contact the wear plate or structures on or in the wear plate during the capping process due to slight deflection of the bottle support structure and/or slight deflection of the bottle or container surface about the bottle support structure. In this arrangement, the bottle support structure counters part or all of the downward force applied by the capping mechanism thereby preventing the deformation or crushing of the body or base of the bottle or container during the capping process. In a further embodiment, the vertical weight of the bottle or container is supported by the wear plate or structures on or in the wear plate at the base of the bottle or container and by the bottle support structure at or about the neck of the bottle or container. In this arrangement, the bottle support structure counters part or all of the downward force applied by the capping mechanism thereby preventing the deformation or crushing of the body or base of the bottle or container during the capping process. In yet a further embodiment, the bottle support structure is adjustable so as to accommodate different sizes of bottle or containers.

In accordance with still another aspect of the invention, the outer periphery of the wear plate is inward of the outermost portion of the bottles or containers. In one embodiment, a rotating ring which constitutes the wear plate is moved along the circular path in conjunction with the rotating star wheel. An inlet conveyor with a plate having a vertical height with respect to the wear plate that is generally greater than the height of the one or more abutments on the wear plate directs the bottles or containers onto the rotating star wheel and above the wear plate and abutments. After the bottle or container passes off the elevated plate, the bottle or container drops toward the wear plate and radially extending abutments in the nests on the wear plate. During the capping operation, the abutments prevent the bottle or container from rotating within the nest as the bottle or container is moved by the star wheel toward the exit end of the capping machine. At the exit end, an outlet conveyor with a lift plate or ramp having a first end positioned even with or below the flat surface of the wear plate and a second end above the surface of the wear plate a distance greater than the height of the abutments engages the bottles or containers and progressively moves them upwardly above the abutments in the nest. In this manner, as the capping machine rotates the wear plate with the upwardly extending abutments, bottles or containers are fed above the abutments and dropped toward the nest. Thereafter, the capping operation takes place as the bottles are moved by the capping machine around the circular path. The upwardly extending abutments prevent rotation of the containers. At the exit end, the conveyor ramp lifts the bottles and directs the capped bottles or containers to the outlet stage of the capping line.

In accordance with still yet another aspect of the invention, the abutments are shaped to fit between the radial recesses in the pedaloid base of the bottle or container. The abutments can have many different shapes such as, but not limited to, bar-like abutments, cylindrical abutments, cone-shaped abutments, rod-shaped abutments and the like. In one embodiment, the one or more abutments on the wear plate are bar-like abutments. In one specific aspect of this embodiment, the length of the bar-like abutment is greater than the width of the bar-like-abutment. In another embodiment, the one or more abutments extend upwardly from the surface of the ware plate a distance of about 0.05–1 inch. In still another embodiment, the one or more abutments are removably secured to the wear plate. Such a securing arrangement for the one or more abutments enables the abutments to be repositioned on the wear plate, removed from the wear plate and/or replaced with other types of abutments to accommodate different types of bottle or containers. In yet another embodiment, the side surfaces of the one or more abutments are shaped to engage a portion of the base of a bottle or containers to prevent the rotation of the bottle or container during the capping process. In one specific aspect of this embodiment, the side walls include substantially linear surfaces. One such configuration includes side walls that are substantially uniformly perpendicular to the surface of the wear plate.

The primary object of the present invention is the provision of bottle support arrangement on a capping machine which reduces or prevents deformation or crushing of the bottle or container during the capping process.

Another object of the present invention is the provision of a bottle support arrangement that supports all or part of the weight of the bottle or container during the capping of the bottle or container.

Still another object of the present invention is the provision of a bottle support arrangement that suspends the base of the bottle or container above the wear plate and components on the wear plate.

Yet another object of the present invention is the provision of an anti-rotation wear plate for use in a standard capping machine, which components on the wear plate prevents rotation of the bottles or containers being capped by such components engaging a structural characteristic on the bottom of the bottle or container as it moves through the capping machine.

Still yet another object of the present invention is the provision of a wear plate as defined above, which wear plate has an upper generally flat surface with one or more protruding elongated abutments so the bottle or container can be moved with the wear plate without rotation.

Another object of the present invention is the provision of a wear plate as defined above, which wear plate includes structural items which define individual nests for the bottle or container, where the items are simple abutments that do not require machining of complex shapes to form nests on the wear plate.

Yet another object of the invention is the provision of an anti-rotation wear plate that merely replaces the standard wear plate of a capping machine to allow ease of retrofitting.

Still another object of the present invention is the provision of a wear plate that includes one or more abutments that are adjustably attachable and/or positionable on the wear plate.

Still yet another object of the invention is the provision of a wear plate that includes one or more abutments, which abutments are shaped to engage a portion of the base of a bottle or container during the capping process.

These and other objects and advantages will become apparent to those skilled in the art upon the reading and following of this description taken together with the accompanied drawings.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring now to the drawings wherein the showings are for the purpose of illustrating preferred embodiments of the invention only and not for the purpose of limiting same,FIGS. 1–3illustrate a somewhat standard capping machine A of the type used in capping a plastic PET bottle B having various sizes and lengths. In accordance with the illustrated embodiment, bottle or container B includes a generally cylindrical body10having diameter10a, center10band an upper threaded neck12connected to the body by diverging top portion14and provided with a circular flange16. The base of container or bottle B is a pedaloid base20, which is quite common in the plastic container industry for use with soft drinks and bottled beverages and is best shown inFIGS. 2,6and7. A pedaloid base is a base with a number of distinct downwardly extending pads with flat surfaces divided by generally diverging recesses. In the illustrated embodiment, pedaloid base20includes five pads20a–20eseparated by five diverging recesses22a–22ebest shown inFIGS. 6 and 7. Each pad has a generally lower flat support surface. This type of bottom structure gives rigidity and stability to a relatively thin bottle B formed by a standard plastic blow molding process. Onto the upper neck12machine A applies a plastic threaded cap C in accordance with standard procedure.

Capping machine A includes a central turret40rotatable about machine axis x and supported on lower base42. In the illustration, turret40includes a centering extension46for receiving standard star wheel50supported by a two piece ring52bolted by bolts54around extension46and fixed onto turret40. The star wheel includes a plurality of outwardly projecting arms56supported by posts60onto ring52. A plurality of downwardly projecting pegs64extend below posts60. These downwardly extending pegs64on each arm56have a plurality of axially spaced adjustable grooves66, which are adapted to receive a bottle stabilizer ring70by way of a mounting housings72that are movable axially along posts64by retracted spring bias pin74in accordance with standard practice. The outward most end of stabilizer ring70includes arcuate recesses76adapted to engage and stabilize the body10of bottle B. In practice, when using the present invention, it may be possible to dispense with the use of stabilizer ring70. A stabilizer structure can be individual members supported on posts64; however, in the illustrated embodiment the stabilizer ring70having a plurality of circumferentially spaced arcuate recesses76, best shown inFIG. 2. Arms56each include an arcuate nesting pocket80with an arcuate outer edge and adapted to receive an upper anti-spin insert82also having an arcuate edge or end84. The upper surface of insert82can be modified or roughened to prevent rotation by frictional engagement with the under surface of flange16; however, this feature is generally not used with the present invention, since spinning on such modifications will cause scuffing of the plastic forming the under surface of flange16. Insert82is designed to be removable from nesting pocket80so that different types and shapes of insert82can be used for different types and shapes of bottles. The top surface of insert82contacts the underside of circular flange16during the application of cap C onto upper neck12.

Capping machine A also includes a plurality of capping heads100rotated about machine axis x in unison with star wheel50by turret40. Each capping head is located above a pocket80of star wheel50and includes a collet102driven by a standard clutch104through a drive unit106, as shown inFIG. 2. As bottles B move in an arcuate path shown inFIG. 1, the capping head with a cap C in collet102is movable downwardly along capping axis y concentric with a bottle or container B held in pocket80. The cap is then rotated until clutch104experiences a proper amount of torque. At that instance, collet102is moved upwardly leaving capped bottle B for further movement through machine A. During the application of cap C onto bottle B, capping head100applies a downward force of about 15–20 pounds onto bottle B.

In accordance with standard practice, a fixed guide plate120is positioned diametrically opposite pockets80of star wheel50and includes an arcuately shaped guide surface or edge122having a center of curvature corresponding generally with machine axis x. Plate120is spaced outwardly from star wheel50a distance necessary to allow guide surface or edge122to hold bottles B in pockets80as they are moved in a circular path by rotation of star wheel50by turret40and in unison with the matching capping heads100. To fixedly locate surface or edge122of plate120in the proper position with respect to the rotating bottles B, support shafts130are provided with upwardly extending threaded portions132. Lock bolts134,136clamp fixed guide plate or back plate120with respect to the rotating bottles B in accordance with standard practice. Shafts130are mounted onto the fixed frame of the capping machine and are spaced circumferentially around machine A at the positions illustrated inFIG. 1. Plate120is vertically positioned so that the top surface contacts the underside of circular flange16during the application of cap C onto upper neck12. As illustrated inFIG. 2, the top surface of insert82and plate120are positioned substantially the same vertical height. Insert82cooperates with plate120to support the weight of bottle B during the application of cap C onto upper neck12.

As shown inFIG. 1, an entrant guide mechanism or conveyor140directs filled bottles B to capping machine A at an entrant end or point140a. In a like manner, exit guide mechanism or conveyor142removes capped bottles B from machine A at an exit end or point142aso the bottle moves to the exit portion of the bottling line.

In operation, filled bottles B are moved in an assembly line fashion through entrant guide mechanism140to capping machine A at point140a. The bottles are then positioned about nesting pocket80of star wheel56and are held in this position by fixed guide plate120and insert82. As turret40rotates in the direction indicated by the arrow inFIG. 1and the arrow inFIG. 2, bottles B move in an arcuate path after the bottle has been captured by machine A. A capping head moving in unison with a pocket80and having a cap C in collet102starts the capping process by rotating cap C over threaded neck12above circular flange16of bottle B. As the bottle is restrained from rotational, it is moved by turret40around machine A. The capping head finalizes the capping operation and is withdrawn from bottle B before the bottle reaches exit guide mechanism or conveyor142at point142a. Inserts82with recesses84and plate120engages the bottles at the lower surface of flanges16. In the past, the upper surface of inserts84were provided with the knife ridges. These knife ridges are not required in practicing the invention, but they may be a part of the standard machine and need not be removed before retrofitting the machine with a wear plate of the present invention.

As so far described, the majority of the components of capping machine A are standard equipment for use in a filling and capping line of a bottling plant. During the capping procedure, the bottle needs to remain stationary in a rotary direction to assure final position of the cap C on the threaded neck12. Bottlers are now insisting upon capping machines which do not depend upon a portion of the pocket82digging into the outer surface of the bottle. However, the elimination of knife ridges on inserts82historically required a greater downward compression force to be applied to the bottle or container being capped. However, the greater downward force resulted in a larger percentage of the bottles being deformed or crushed during capping. The bottle capping machines of Martin U.S. Pat. No. 5,826,400 and Peronek U.S. Pat. No. 5,934,046 overcome the problem of using large downward forces; however, limited problems still remain concerning bottle deformation and crushing when using the machine of Martin '400 and to a much lesser extend using the machine of Peronek '046. The present invention accomplishes the objective of not digging into the outer surface of the bottle during capping by countering the downward force applied by capping head100at or about the neck of the bottle and by providing a series of bottle receiving nests N on a wear plate which nests N include one or more abutments that are adapted to interfere with the rotation of the bottle or container during the capping process.

As best shown inFIG. 2, insert82and fixed guide plate120engage the lower surface of flange16during the capping process. Therefore, the distance to which base20of bottle B is elevated from the surface of nest N during the capping process is controlled by insert80and fixed guide plate120. The distance of elevation of base20from the surface of nest N can be increased or decrease by adjusting the vertical position of fixed guide plate on the threaded portion of shaft130and by selecting an insert82having thickness that engages the lower surface of flange16at substantially the same vertical elevation as the fixed guide plate. By use of this arrangement, the vertical position of fixed guide plate120can easily be adjusted to accommodate various sizes and types of bottles. In addition, insert82is removable and replaceable with other inserts to match the vertical adjustment of the fixed guide plate. As can be appreciated, post60can includes one or more threaded portions or grooves to enable the vertical height of projecting arms56to be correspondingly adjusted with the vertical height of the fixed guide plate. In this arrangement, insert82need not be removed and replaced with a thicker or thinner insert.

In operation, the vertical height of the top of the fixed guide plate and the top of insert82are substantially the same. The vertical height is selected for each type of bottle such that the weight of the bottle is supported by the top of the fixed guide plate and the top of insert82during the capping operation. By supporting the weight of the bottle B at the neck of the bottle, cylindrical body10and base20of the bottle will not be deformed or crushed by the downward force applied to the neck of the bottle by capping heads100during the capping process. As shown inFIG. 2, the distance of the top surface of fixed guide plate120from upper flat surface202of wear plate200is designated by distance E. The distance of the bottom surface of flange16from the bottom of bottle B is designated by distance D.FIG. 2illustrates that distance E is greater than the distance D resulting in the base of bottle B being elevated from upper flat surface202of wear plate200. During operation, base20is spaced a sufficient distance from upper flat surface202that base20does not contact upper flat surface202when cap C is inserted onto bottle B.

The rotation of bottle B during the capping process is prevented by the structures on wear plate200. As shown inFIG. 2, wear plate200has an upper flat surface202and an outer periphery204. The outer periphery of the wear plate is reduced in diameter such that a portion of the base of the bottle extends beyond the edge of the wear plate. As can be appreciated, the wear plate can be sized such that no portion of the base of the bottle extends beyond the edge of the wear plate. Wear plate200is formed from a ring including two interlocked sections210,212having tongues214and grooves216, as best shown inFIG. 3. To fixedly secure the sectioned ring or wear plate200onto base42of turret40, sections210,212are provided with a series of arcuate slots220, some of which receive bolts222extending into base42. In this manner, wear plate200is locked onto the turret and rotates in unison with star wheel50with nests N being aligned with the capping head100and rotates in unison with the heads, which heads are moved downwardly to cap the bottles as the bottles are conveyed between inlet point140aand outlet point142ain a circular path concentric with machine axis x.

As shown inFIG. 3, each of the individual nests N has an inner area230constituting a portion of flat surface202and having a center232aligned with center10bof bottle B where the bottle is positioned its individual nest N. As best shown inFIGS. 3,4and7, three bar-like abutments240,242and244are manufactured in accordance with the procedure set forth inFIGS. 10–13, and are assembled as shown inFIGS. 4 and 5. As can be appreciated, other abutment shapes can be used. In addition, more than three or less than three abutments can be used. The abutments extend radially outward from center232. Abutment240points toward axis x and abutments242,244are spaced from abutment240by an angle determined by the formula 360°/X, wherein X is the number of pads on pedaloid base20of bottle B.

Inlet conveyor140includes flange engaging tracks250,252for guiding bottles B to inlet point140aof wear plate200. Bottom plate260has an upper surface262, as best shown inFIG. 8. Abutments240,242and244have a vertical height a. In practice, vertical height a is about 0.05–0.5 inch and preferably about 0.125 inches, as shown inFIG. 13. Upper surface262has a height b above surface202. In this manner, as bottles B move along conveyor140toward point140a, as shown inFIG. 8, the bottles are above the top of the bar-like abutments240,242and244. As the bottle B is moved forward, it drops toward nest N, as shown at the left ofFIG. 8. The distance the bottle drops toward nest N is controlled by the vertical position of the top of fixed guide plate120and the top of insert82. As shown inFIGS. 6,6A,6B,8and9, base20of bottle B does not contact upper flat surface202of wear plate200. After the bottle in positioned in the nest, the neck of the bottle is engaged by the capping head which attempts to rotate bottle B. Thus, the bottle rotates into a position where the rod-like abutments are positioned between the recesses of base20. The abutments thereafter prevent rotation of the bottle as the capping procedure is accomplishes. During the insertion of cap C on bottle B, the weight of bottle B does not rest on the abutments as shown inFIGS. 6A and 6B. The bottom surfaces of recesses of base20spaced above the top of the abutments. In practice, the space is about 0.0001–0.5 inch and preferably about 0.01–0.25 inch. When the space is greater than zero, the full weight of bottle B is supported by fixed guide plate120and insert82during the capping process. Since the abutments and/or wear plate to not support the weight of the bottle, the body and base of the bottle will not be deformed, crushed or otherwise damaged when downward forces are applied to the neck of the bottle as the bottle cap is inserted onto the neck of the bottle. Although the bottom surfaces of the recesses of the bottle are spaced above the abutments, the abutments still prevent the bottle from rotating. As shown inFIG. 6B, a portion of the abutments extend into the recesses without touching the surface of the recesses. However, when the bottle attempts to rotate during the capping process, the sides of the recesses move into contact with the sides of the abutment, thus stopping further rotation during the capping process.

An alternative embodiment of the invention is shown inFIG. 6. InFIG. 6, base20of bottle B is spaced above guide plate120but contacts the top of one or more abutments. In this arrangement, the weight of the bottle, prior to being capped, is supported by the abutments and guide plate120and insert82. When the downward force during capping is applied to the top of the bottle, guide plate120and insert82counter all or part of the downward force thereby reducing or preventing deformation or crushing of the body and/or base of the bottle.

Although not specifically illustrated, the vertical position of the top of fixed guide plate120and the top of insert82can be selected so that distance D and E are equal. In this arrangement, the bottom of flange16contacts fixed guide plate120and insert80and base20contacts upper flat surface202. The top of fixed guide plate120and the top of insert82still counter most or all of the downward force applied to the bottle during capping process. As can be appreciated, the concept of countering the compressive and downward forces on the body and base of the bottle during the capping process can be successfully applied to other types of capping machines. For example, the capping machine disclosed in Martin U.S. Pat. No. 5,826,400 can be modified to support the bottle under the circular flange on the neck of the bottle. The support under the circular flange is positioned so as to counter the compressive and downward forces of the body and base of the bottle during the capping process. The base of the bottle can be suspended above the bottle supporting surface or positioned so that the base is just touching the bottle supporting surface. The fingers in the bottle nest of Martin U.S. Pat. No. 5,826,400 function similarly to the abutments of the present invention.

InFIG. 9, the bottle removal mechanism is illustrated. Outlet conveyor142removes the capped bottles from wear plate200at exit point142aby using a plate270having a height b which is above the top of abutments240,242and244and generally at the height of plate260. Ramp272has a first end274at or below surface202and a second end276merging with the top of plate270. Consequently, as the capping machine moves bottles B to the left, as shown inFIG. 9, the bottle engage ramp272which lifts the bottles from nests N onto the top of plate270for exit into the remainder of the capping line in accordance with standard practice. As illustrated inFIG. 1, tracks280,282engage the flange16on each bottle to capture the bottles as they are moved away from capping machine A. In accordance with the invention, periphery204is substantially inboard of the outermost portion of bottles B as they move along wear plate200. In practice, the periphery is a circle concentric with machine axis x and spaced outwardly from center232of each individual nest N a distance in the range of ¼ to ½ inch. This allows a portion of the base20of each bottle to extend outwardly from periphery204so bottle can be dropped in position with nest N and lifted from the nest after the capping procedure.

Rod-like abutments240,242and244can be produced in accordance with a variety of manufacturing processes and assembled onto plate200by various procedures, such as soldering, welding, brazing, adhesive, bolting, screwing or machining away a top portion or layer of plate200to leave the abutments. The procedure of manufacturing and assembling the rod-like abutments is set forth inFIGS. 4,5and10–14. Referring toFIGS. 10 and 11, a rod300having a diameter of 0.370 inches for its outer surface302is cut to the desired length, indicated to be 1.312 inches. As can be appreciated, the rod can have other dimensions depending on the size and type of bottle to be capped. The bar is formed from various materials, such as, but not limited to metals, plastics, ceramics, fiberglass, composite materials and the like. Preferably, the bar is made of a metal such as aluminum. One end of the rod300is mounted in the chuck of a lathe as shown inFIG. 13. Then a generally semi-spherical end304is turned on at one end of bar300. In practice, a radius of 0.125 inches is employed, which does not result in an exactly semi-spherical shape. Surface302remains cylindrical. Bar300is then reversed in lathe L and a second end304is provided at the opposite end of the bar stock. Thereafter, bar300is positioned in clamps of a surface grinder where a flat surface306is ground onto one side of the rod to a depth slightly less than the radius of the bar. This abutment is then provided with holes308that are drilled and tapped so the bar-like abutments240can be mounted in appropriate slots310cut into surface202of wear plate200, as best shown inFIGS. 4 and 5. Holes312,314in plate200receiving tapered headed bolts320for fixedly securing bar-like elements in slots310. Various other arrangements could be used for producing and mounting the abutments. The abutments would have a variety of shapes as long as they generally match the recesses in the bottom of bottles B.

One alternative abutment shape is illustrated inFIG. 14. The bar is rectangular in shape having sides330and a top surface332. The sides320of bar240are substantially perpendicular to the surface of wear plate200. The straight sides of the abutment, in some applications, function better at preventing the rotation of the bottle during the capping process. In some applications, the curved surfaces allow the bottom on the bottle to cam over the top of the abutment during the capping process. In these applications, the straight sided abutments prevent this camming of the bottles.

The invention has been described with reference to a preferred embodiment and alternates thereof. It is believed that many modifications and alterations to the embodiments disclosed will readily suggest itself to the those skilled in the art upon reading and understanding the detailed description of the invention. It is intended to include all such modifications and alterations insofar as they come within the scope of the present invention.