1. Field of the Invention
This invention concerns a method and apparatus to securely seat non-flat topped closures onto containers, particularly closures that require pressure to be snapped-on to containers.
2. The Related Art
Closures with non-flat top-surfaces are difficult to properly seat onto their containers. Known capping systems apply excessive force to achieve closure securement. Unfortunately, the excessive force may cause damage to the closure and/or container. Especially where similar but different sized closures/containers need to be processed through a common capping apparatus, adjustment of application of forces without using expensive equipment may be difficult to achieve.
Compression belt systems for capping are commercially available. For instance, Kinsley Inc. of Doylestown, Pennsylvania markets custom container handling equipment based on compression belts. These belts are inadequate to handle closures with curvilinear top surfaces; the full pressure of the belt back-stopped by a flat rigid plate is applied only to the highest area along the contoured closure top surface. The indiscriminate application of force often damages the closure/container.
U.S. Pat. No. 5,937,616 (Ray) discloses a vial capping machine that includes two rollers and a table supported by a frame. The rollers are rotatably driven by a motor. The table supports a tray of vials in which caps have been set into their openings but not fully inserted. As the tray is inserted into the entrance end of the machine, the first driven roller engages the caps of the vials, partially inserting the caps and driving the tray towards the second roller. The second roller engages the caps of the vials, and fully inserts the caps into the vials, and drives the tray to the exit end of the machine. Technology disclosed herein does not solve the problem of properly and securely seating closures that have curvilinear shaped top surfaces.
A method is provided for securely seating a closure with curvilinear top surface onto a container in a manner avoiding damage from excessive force applied to the closure in a capping apparatus, the method including:
(i) conveying to a cap locking unit a container with separate closure, the container being supported on a moving conveyor and the closure being insecurely seated on the container;
(ii) contacting the curvilinear top surface of the closure with a circulating compression belt, the compression belt being a component of the cap locking unit; and
(iii) applying pressure to the curvilinear top surface of the closure via a dancer, the dancer communicating with an inner surface of the compression belt and including a leading and a trailing leg converging from a common pivot, ends of the leading and trailing legs being distant from one another no longer than a length of the closure.
An apparatus is providing for securely seating a closure with curvilinear top surface onto a container to avoid damage from excessive force applied to the closure in a capping process, the apparatus including:
(i) a circulating compression belt for contacting the curvilinear top surface of the closure; and
(ii) a dancer contacting an inner surface of the compression belt, the dancer including leading and trailing legs converging from a common pivot, ends of the leading and trailing legs being distant from one another no longer than a length of the closure.
Further advantages and features of the present invention will become more apparent from consideration of the drawing in which:
Now we have devised a method and apparatus which can securely seat closures with curvilinear top surfaces onto containers without causing damage to some of these articles. The method and apparatus has the further benefit over prior systems of reducing excessive friction. This inhibits wear on the loaded components. Also with reduced friction, there is lower energy consumption.
Around a mouth 22 of the container as illustrated in
The compression belt is driven by a driving roller 30 at one end of the cap locking unit and an idler roller 32 at an opposite end.
A support frame 34 commonly supports the driving roller and idler roller. A support bracket 36 projects downward and forms part of the frame 34. A vertically elongated window 38 is formed in the support bracket. Rod 40 traverses through window 38 and is held in position by hexagonal nut 42 or in an alternative embodiment by positioning knob 142. A dancer 43 is supported on rod 40 and includes leading leg 44 and trailing leg 46 oriented away from one another. At an end of the leading and trailing legs and distant from the rod are respective pressure rollers 48 and 50. The leading and trailing legs at a bottom most tangent to the rollers between their midpoints are separated by a length S. Length S ordinarily will be no longer than the longest dimension (in the conveyance direction C) of closure 3.
The dancer 43 shown in
Advantageously, the width W2 of the pressure rollers 48 and 50 may be slightly larger than a largest width W of the closure. This width (W2) of the rollers allows processing of different width sized closures/containers.
According to the method, a closure is placed over but not securely seated onto a container. The combination is supported on the conveyor which transports the combination to the cap locking unit. At that point the overhead moving compression belt contacts the top surface of the closure. Next, the leading leg 44 via pressure roller 48 contacts a flanking first area 16 on the closure. This is followed by trailing leg 46 via pressure roller 50 contacting the flanking second area 18 of the domed top surface 12 of the closure. By simultaneous pressure from both the leading and trailing legs onto the domed top surface, the closure is forced downward over the nibs to securely seat on the container.
The compression belt speed is synchronized with the speed of the conveyor. Speeds in some embodiments may range from 50 to 1000 units per minute on closures of 2 to 5 inches in length. It is the pressure rollers of the dancer assembly that navigate the pitches of the closure top surface. Maximum application force is applied only within the short distance S under the dancer arms. This insures selective pressure application. The result is less closure/container breakage, less equipment wear, lower energy use and quick changeability to engage different sized packages.
The method and apparatus also permits capping of different sized snap-on closures and does so in a rapid conversion without necessitating additional equipment. For instance, containers of greater height than a first set of capped containers can be accommodated simply by loosening nut 42 and moving the dancer upward in the supporting bracket 36 within the elongate window 38. For closures of greater length, the dancer may be replaced for one with a greater length S between the legs. Thus, closures/containers of larger height and length dimensions can be capped with minimum time lag conversion of equipment after a different sized closure/container requires a capping operation.
Filing Document | Filing Date | Country | Kind | 371c Date |
---|---|---|---|---|
PCT/US10/28085 | 3/22/2010 | WO | 00 | 4/6/2011 |