Abstract
A method for cutting a moving source material including: rotating a cutting cylinder including a blade; positioning a structural member in spaced relation from the cutting cylinder, wherein the space between the cutting cylinder and the structural member receives the source material; and positioning an anvil in the space. The anvil engages the source material when it is displaced between the cutting cylinder and the structural member. The method also includes: directing the blade into contact with the source material, whereupon the source material is pressed against the anvil and is severed by the blade, and the anvil is displaced by the cutting blade from a first retracted position to a second activated position; and applying an increasing biasing force to the moving anvil as it is displaced toward the second activated position so as to direct the anvil back to its first retracted position.
Claims
1. A method for rotary pressure cutting a moving source material comprising the steps of: rotating a cutting cylinder about its longitudinal axis, wherein said cutting cylinder includes a lateral peripheral portion and a cutting blade extending outwardly from said lateral peripheral portion; positioning a structural member adjacent to, and in spaced relation from, said cutting cylinder, wherein the space between said cutting cylinder and said structural member is adapted to receive the moving source material; positioning an anvil in the space between said cutting cylinder and said structural member, wherein said anvil is adapted to engage and support the moving source material when the source material is displaced between said cutting cylinder and said structural member; directing the rotating cylinder's cutting blade into contact with the moving source material, whereupon said moving source material is pressed against said anvil and is severed by said cutting blade, and said anvil is displaced by said cutting blade from a first retracted position to a second activated position; applying an increasing biasing force to said moving anvil as it is displaced toward said second activated position so as to reverse the movement of said anvil and direct the anvil back to its first retracted position, wherein said biasing force is produced by increasingly bending each of a pair of flexible, resilient members coupled to said anvil as said anvil approaches said second activated position, whereupon release of deflection of said pair of flexible, resilient members causes said flexible, resilient members to return said anvil to said first retracted position in preparation for the next cut of the moving source material; and coupling said anvil to each of said flexible resilient members by means of a respective semispherical ball bearing arrangement for reduced mass and increased reciprocating speeds of said anvil upon release of deflection of said pair of flexible resilient members from a position of greater bending to a position of reduced bending.
2. The method of claim 1, wherein deflection of said flexible, resilient members and the associated biasing force exerted on the anvil increases as the anvil approaches the second activated position.
3. The method of claim 2 further comprising the step of providing each of said flexible, resilient members in the form of an elongated leaf spring or a cantilever spring.
4. The method of claim 3, wherein said semispherical ball bearing arrangements guide said anvil along a path defined by said leaf springs or said cantilever springs.
5. The method of claim 1, wherein said flexible, resilient members allow said anvil to over-travel said cutting blade in the direction of said second activated position so as to more securely engage said anvil with said flexible, resilient members and maintain said anvil in a quasi-stable position to avoid said cutting blade in the event of a jam-up.
6. The method of claim 5 further comprising the step of retaining said anvil in said over-travel position followed by returning said anvil to said first retracted position upon release of deflection of said flexible, resilient members.
7. The method of claim 1, wherein the step of increasingly deflecting each of said flexible, resilient members includes bending each of said flexible, resilient members in two planes.
8. The method of claim 1 further comprising the step of providing each of said flexible, resilient members with a selected contour along a portion of the length of said flexible, resilient member, wherein said flexible, resilient member's selected contour determines its progressive spring rate.
9. The method of claim 1, wherein said semispherical ball bearing arrangements stabilize said anvil in pitch as said anvil is displaced on said flexible, resilient members.
10. The method of claim 1 further comprising the step of applying a selective force to said anvil in displacing said anvil from said second activated position to said first retracted position by providing the pair of flexible, resilient members with selected dimensions, including the thickness of each of said flexible, resilient members.
11. The method of claim 1 further comprising a step of adjusting the position of said pair of flexible, resilient members relative to said anvil for changing the deflection of said flexible, resilient members and the force applied to the anvil in displacing the anvil from said second activated position to said first retracted position.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
(1) The appended claims set forth those novel features which characterize the invention. However, the invention itself, as well as further objects and advantages thereof, will best be understood by reference to the following detailed description of a preferred embodiment taken in conjunction with the accompanying drawings, where like reference characters identify like elements throughout the various figures, in which:
(2) FIG. 1A is a simplified schematic side view of prior art anvil strip and its mounting;
(3) FIG. 1B is a simplified schematic top view of prior art anvil strip and mounting;
(4) FIG. 2A is a simplified schematic top view of another prior art anvil strip and mounting shown in a retracted position;
(5) FIG. 2B is a simplified schematic top view of the prior art anvil strip and mount of FIG. 2A shown in an activated position;
(6) FIG. 3A is a simplified schematic top view, retracted position of an alternate embodiment of the prior art anvil strip and mount of FIG. 2A;
(7) FIG. 3B is a simplified schematic end view, retracted position of an alternate embodiment of the prior art anvil strip and mounting of FIG. 3A;
(8) FIG. 3C is a simplified schematic top view, activated position of an alternate embodiment of FIG. 3B;
(9) FIG. 4A is a simplified schematic top view, retracted position of an inventive embodiment of the anvil strip and mounting and guiding components;
(10) FIG. 4B is a simplified schematic end view, retracted position of an inventive embodiment of the anvil strip and mounting and guiding components;
(11) FIG. 4C is a simplified schematic front view of an inventive embodiment of the anvil strip and mounting/guiding components;
(12) FIG. 4D is a simplified schematic top view, activated position of an inventive embodiment of the anvil strip and mounting/guiding components;
(13) FIG. 4E is a simplified schematic side view of the inventive guide roller assembly with a revised contour for improved pitch-mode anvil strip stability;
(14) FIG. 5A is a simplified schematic top view, retracted position of an alternate inventive embodiment of the anvil strip and mounting/guiding components;
(15) FIG. 5B is a simplified schematic end view, retracted position of an alternate inventive embodiment of the anvil strip and mounting/guiding components;
(16) FIG. 5C is a simplified schematic front view, retracted position of an alternate inventive embodiment of the anvil strip and mounting/guiding components;
(17) FIG. 5D is a simplified schematic top view, activated position of an alternate inventive embodiment of the anvil strip and mounting/guiding components;
(18) FIG. 5E is a simplified schematic end view, activated position of an alternate inventive embodiment of the anvil strip and mounting/guiding components;
(19) FIG. 5F is a simplified schematic front view, activated position of an alternate inventive embodiment of the anvil strip and mounting/guiding components;
(20) FIG. 6A is a simplified schematic side view of the anvil strip working in conjunction with a blade, belt, and cylinder;
(21) FIG. 6B is a simplified schematic side view of a further inventive embodiment of the anvil strip and mounting/guiding components in a retracted position and working in conjunction with a blade, belt, and cylinder;
(22) FIG. 6C is a simplified schematic side view of a further inventive embodiment of the anvil strip and mounting/guiding components in an activated position and working in conjunction with a blade, belt, and cylinder;
(23) FIG. 7A is a simplified schematic side view of a further inventive embodiment of the anvil strip and mounting/guiding components in a retracted position and working in conjunction with a blade, belt, and cylinder;
(24) FIG. 7B is a simplified schematic side view of a further inventive embodiment of the anvil strip and mounting/guiding components in an activated position and working in conjunction with a blade, belt, and cylinder;
(25) FIG. 8A is a simplified schematic side view of a further enhanced inventive embodiment of the anvil strip and mounting/guiding components in a retracted position and working in conjunction with a blade, belt, and cylinder;
(26) FIG. 8B is a simplified schematic top view of a further enhanced inventive embodiment of the anvil strip and mounting/guiding components in a retracted position;
(27) FIG. 9A is a schematic side view of a commercial embodiment of the invention showing the anvil strip in a retracted position;
(28) FIG. 9B is a schematic side view of a commercial embodiment of the invention showing the anvil strip in an activated position;
(29) FIG. 9C is a schematic side view of a commercial embodiment of the invention showing the anvil strip in a quasi-static kicked-out position; and
(30) FIG. 9D is a schematic side view of a commercial embodiment of the invention showing the installation of an anvil strip assembly using a push/hook tool to push the anvil strip assembly into its gap or groove.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS OF THE INVENTION
(31) FIGS. 1A and 1B illustrate a prior art anvil strip and mounting system. The anvil strip 10 is configured to reciprocate in the direction noted by arrow 11 since the anvil strip 10 is mounted on slide blocks 12 which are free to slide on slide rods 13 which are rigidly supported by frame member 13f. In FIGS. 1A and 1B, the anvil strip 10 is shown in a retracted position where it's leftwards travel is limited by stops 14 and is preloaded in the retracted position by springs 15. Please note that terms: left, right, up, down, etc., are selected to simplify and illustrate the various mechanisms and methods and are not intended to limit this disclosure.
(32) Anvil strip 10 is propelled in a rightward direction when cutting blade 16, which is mounted in a rotating cutting cylinder (not shown), contacts the anvil strip 10 as in FIG. 1A. The rotational direction of the cutting blade 16 is illustrated by the arrow 17 and the portion of the swing of blade 16 is further indicated by phantom line 18.
(33) To simplify the drawings, the material to be cut, such as poly, paper, metallic, rubber, etc., films is not shown in FIG. 1A or 1B, but would be pinched between the tip of blade 16 and anvil strip 10.
(34) As the blade 16 tip pinches the material to be cut, it further presses down on anvil strip 10 which presses anvil strip into contact with vacuum belt, or belts, 19 which travel in a direction shown by arrow 19d. This tends to accelerate anvil strip 10 in a rightwards direction, as does the horizontal component of the tangential motion of blade 16 tip. Anvil strip 10 is preferably comprised of steel, carbon fiber composite material, or a combination of steel/cushion/steel, steel/carbon fiber composite or of anvil strips with coatings such as of chromium by Armoloy of DeKalb, Ill., titanium carbide, titanium nitride, or ceramic by CemeCon Inc. of Horseheads, N.Y., or diamond by Diamond Tool Coatings LLC of North Tonawanda N.Y.
(35) The pressure between blade 16 tip and anvil strip 10 severs the material to be cut (again, not shown). Once the material to be cut is severed, the blade 16 continues its rotation on path 18 and the bladetip moves upwards and reduces its force on anvil 10 and then comes out of contact with anvil strip 10. The springs 15 having been further compressed by the motion of anvil strip 10 which push the anvil 10 to the left and back into contact with the stops 14 in a first retracted position as shown in FIGS. 1A and 1B. In a typical Vista window applicator machine at normal operating speed, the total travel of anvil strip 10 may be approximately . There are typically some left-right oscillation as the anvil assembly bounces off the stops 14. There may also be some upwards oscillation of the anvil 10 as it comes out of contact with belts 19. The anvil strip of prior art embodiments, however, is relatively thick (typically 0.028-0.042) and rigid and so undergoes limited vertical oscillation.
(36) A metal anvil strip 10 is contemplated for use in most intended applications for the rotary pressure cutting apparatus of the present invention. However, the present invention is not limited to use of a metal anvil strip, as other compositions of the anvil strip such as high strength, high impact multi-layer laminates or coatings of ceramic or carbon fiber materials could be used for various applications.
(37) FIGS. 2A and 2B illustrate a further prior art embodiment which has two ball bearings 22 that replace the slide blocks 12 of FIGS. 1A and 1B and two rods 23 loaded in a bending mode that replace the coil springs 15 in FIGS. 1A and 1B. The anvil strip 20 is connected to the two ball bearings 22 such as those provided by VXB.com Ball Bearings of Anaheim, Calif. that have a V or U groove in the outer race so that the bearings 22 stay engaged with rods 23. The rods may be initially installed at a divergent angle as shown in FIG. 2A. The anvil strip 20 and bearings 22 are sized so that when installed on the rods, the rods bend elastically creating a tension on the anvil strip 20. When the blade (not shown) engages the anvil strip 20 and presses it into contact with the vacuum belts (not shown) in a manner similar to that described above in conjunction with FIGS. 1A and 1B, the anvil strip 20 is driven to the right. Due to the divergent angle of the rods, the rods are bent further as the anvil strip 20 moves to the right as shown in FIG. 2B and this increases tension in the anvil strip 20. After the cut, as the blade rotates upwards from the anvil strip, the tension in anvil strip 20 and the geometry of the divergent rods 23 cause the anvil strip 20 to reciprocate back leftwards to its initial position shown in FIG. 2A until anvil strip 20 contacts stops 24. This embodiment provides reduced friction and reduced reciprocating mass in comparison to the apparatus shown in FIGS. 1A and 1B, which allows for increased reciprocating rates and higher operating speeds.
(38) FIGS. 3A, 3B, and 3C illustrate a further prior art embodiment very similar in concept to FIGS. 2A and 2B, however, the anvil strip 30 is attached differently to the ball bearings such as with a pair of links 30L. In one commercial embodiment, links 30L were a simple nylon tie-strap such as provided by Thomas & Betts of Memphis, Tenn. which was routed through the ball bearing 32 and a hole in each end of the anvil strip 30. The tie wraps 30L also provided a fuse effect where one or both tie wraps 30L would break or sever in the case of a jam-up and allow the anvil strip 30 to be ejected with less likelihood of damage to the spring rods 33 or anvil strip. In practice, the tie straps 30L tended to fail regularly as the reciprocating motion caused edges of anvil strip 30 to gradually cut through the tie wraps 30L. Also the tie wraps 30L were rather small and difficult for operators to replace properly.
(39) FIGS. 4A, 4B, 4C, and 4D illustrate an improvement of the anvil strip mounting in accordance with one embodiment of the present invention. Anvil strip 40 is equipped with a bearing assembly 42 at each end. Bearing assembly 42 is comprised of an upper ball bearing 42bbu mounted in a semispherical roller 42su and lower ball bearing 42bbl mounted in a semispherical roller 42sl as shown in FIGS. 4B and 4C. The upper and lower assemblies are fastened onto anvil 40 via a small screw, or pivot pin, 41 from top and bottom into an axle, screw and nut, rivet, or the like. Relative motion is between a semispherical roller and its associated pivot pin.
(40) The bearing assemblies support and guide the anvil strip 40 in a track or groove 43g created by the space between cantilever springs 43. Springs 43 are rigidly supported by frame members 4f.
(41) FIGS. 4A and 4B show the anvil strip 40 in a retracted position just as blade 46 is rotating into contact with anvil 40 to initiate a rightwards motion in anvil strip 40. The motion is resisted by the diverging cantilever springs 43, which bend further inwardly as the anvil strip moves to the right as seen in FIG. 4D. After the blade 46 rotates upwards and out of contact with the anvil strip 40, the anvil strip is free to retract leftwards until it contacts stops 44. The return force can be adjusted by providing stiffer or weaker leaf springs, which have been constructed from 0.015 thick spring steel, but could be thicker or thinner, or by adjusting the relative length of the leaf springs 43 in relation to the retracted position of the anvil strip 40 relative to frame members 43f.
(42) The contour of rollers 42su and 42sl may be selected to provide varying amounts of guiding relative to the slot or gap 43g. For example, a flatter, or more squashed, roller assembly 42a, as seen in FIG. 4E, will provide more anvil strip horizontal stability and guiding relative to pitch than a more spherical roller assembly. Conversely, a more spherical roller assembly allows the anvil strip to rotate, i.e., change pitch, more easily such as shown in FIGS. 4B and 4C for bearing assembly 42.
(43) FIGS. 5A, 5B, 5C, and 5D illustrate a further inventive embodiment of the anvil strip 50 mounting. FIGS. 5A, 5B, and 5C illustrate the anvil strip 50 in a retracted position. A vacuum belt 49 is shown in FIG. 5D. FIGS. 5D, 5E and 5F illustrate the anvil strip 50 in an activated position, i.e., during or after a cut has occurred. Roller assemblies 52 are very similar in construction to roller assemblies 42 shown in FIGS. 4A-4E. Cantilever springs 53 are supported by frame members 53f. Springs 53 may be contoured in the manner shown in FIGS. 5B and 5E, i.e., to provide a converging gap. The gap 53g guides the rollers 52 and consequently the anvil strip 50. The converging gap 53g causes additional spring deflection and tension in the anvil strip 50 as the anvil strip is cycled to the right. The additional spring deflection is shown in FIG. 5F. This increasing spring force thus acts to drive the spring to the left during and after a cut as described previously. A progressively increasing spring force could also be provided by mounting the springs 53 so that they diverge in the top view (such as FIG. 5D) so that as anvil strip 50 moves to the right, the springs 53 are increasingly directed more inwardly towards one another.
(44) FIGS. 6A, 6B, and 6C show a further alternative embodiment similar to the embodiment of FIGS. 5A-5F. FIG. 6A schematically shows an anvil strip 60 supported on top of a vacuum belt or belts 69 on a portion of the belt routing where the belt 69 is supported on a roller 69r. In FIG. 6B the anvil strip 60 is in a retracted position and the roller assemblies 62 are in an expanded, or radius, portion of gap 63g. As the anvil strip 60 is cycled through its normal working motion, towards the right, the roller assemblies transition to a straight, linear portion of gap 63g. Thus, the anvil strip 60 can transition from a curved path to a straight path, and vice versa, to follow the top surface of belt or belts 69. Similar to FIGS. 5A-F, the spring deflection can be increased as the anvil strip 60 moves to the right either by converging the gap 63g, diverging the springs 63 as seen from the top (a top view is not shown for FIG. 6), or a combination of both techniques.
(45) FIGS. 7A and 7B show an enhanced embodiment of the invention. FIG. 7A shows anvil strip 70 in a retracted position and FIG. 7B shows anvil strip 70 in an activated position. The gap 73g is wider in the range of desired travel and narrow beyond the normal range. This gap configuration allows the normal range of motion to be defined and travel beyond that range substantially increases the spring force serving to return anvil strip 70 back to its normal range of motion. In this way, a jam-up, which may tend to drive the anvil strip 70 further to the right than normal, allows the anvil strip 70 to over-travel its normal range of motion, while reducing the likelihood of damage to the anvil strip 70 and its associated mountings. In the event of an over-travel, when the roller assemblies are in a narrower, parallel portion of the gap 73g, the anvil strip may be in a quasi-stable position, where it will remain until manually or otherwise reset in its normal range of travel. This permits the anvil strip 70 to remain out of the way of rotating blade path 76 when a jam-up occurs.
(46) FIGS. 8A and 8B illustrate a still further enhanced embodiment of the invention. FIG. 8A shows a refined version of springs 83. Springs 83 include the enhanced groove configuration of springs 73 shown in FIGS. 7A and 7B and, in addition, include a revised outer contour that provides a varying spring rate. For example, the right side of springs 83 has a stiffer spring rate than the left side of spring 83 as shown in FIG. 8A. The spring rate may be varied by the amount and shape of the cut away portions 83ca. This allows the activating and return forces to be tuned by the machine builder and for that matter by the end user. The machine builder can stock springs 83 with various contours to provide for different speed ranges and cutting conditions. Similarly, the springs may be supplied in different thicknesses to provide different spring rates. The different spring thicknesses can be supplied in a single thickness or additional thicknesses can be stacked in the manner of a leaf spring to substantially alter the spring rate in controlling the position of the anvil strip 80.
(47) FIGS. 9A-D show a simplified schematic view of a commercial embodiment of the inventive anvil strip arrangement. The anvil strip assembly 90, with anvil strip and semispherical bearings 92 is installed in the gap 93g in the spring 93 using an installation tool 90t at each end of the anvil strip assembly. The spring 93 is designed to allow relatively convenient and safe access to the gap 93g. Tool 90t is used to push the anvil strip 90 into the gap 93g into a retracted position as shown in FIG. 9A. Tool 90t may also include a hooked end so that it can also be used to pull and/or remove the anvil strip assembly 90 out of the gap 93g.
(48) In the retracted position shown in FIG. 9A, a partially looped belt 94 provides a stop which engages the semispherical bearing assembly 92 on each end of the anvil strip 90. Belt 94 may be adjusted to define the retracted position of anvil strip assembly 90 by varying the length of belt captured between aperture flanges 94c. In FIG. 9A, when the anvil strip assembly 90 is stopped by the belt 94 in the retracted position, the semispherical bearing 92 will be in contact with belt 94, however for clarity, this contact is not shown in FIG. 9A.
(49) The anvil strip assembly 90 is shown in an activated position in FIG. 9B, where the blade (not shown) has caused the anvil strip assembly 90 to move towards the right as described previously herein.
(50) In FIG. 9C, the anvil strip assembly 90 is shown in a kicked out position in the event a material jam-up or other malfunction has exerted higher than normal forces on the anvil strip assembly 90. The kicked-out position is quasi-static, that is, the anvil strip assembly 90 will stay in the kicked-out position until it is reset, typically by manually pushing the anvil strip assembly 90 towards the left using a tool or tools (one at each end of anvil assembly 90) such as the installation/removal tool 90t provided by McMaster Can Supply of Elmhurst, Ill. Other manual or automated means could be provided for resetting anvil strip assembly, such as unlatching levers (not shown), pneumatic cylinders made by Clippard of Cincinnati, Ohio, or solenoid actuators such as supplied by Magnetic Sensor Systems of Van Nuys, Calif.
(51) While particular embodiments of the present invention have been described, it will be obvious to those skilled in the relevant arts that changes and modifications may be made without departing from the invention in its broader aspects. Therefore, the aim in the appended claims is to cover all such changes and modifications that fall within the true spirit and scope of the invention. The matter set forth in the foregoing description and accompanying drawings is offered by way of illustration only and not as a limitation. The actual scope of the invention is intended to be defined in the following claims when viewed in their proper perspective based on the prior art.
