Abstract:
An apparatus and method for perforating, cutting, or engraving a workpiece using a focused laser system to produce a focused laser. The apparatus includes a workpiece former having a complex shape to which the workpiece substantially conforms. The apparatus also includes a positioner that makes an adjustment to keep the focused laser substantially focused on the workpiece as the positional relationship between the workpiece former and the focused laser system changes to an operating position that changes the distance between the workpiece and the focused laser system due to the complex shape of the workpiece former.

Description:
REFERENCE TO RELATED APPLICATIONS 
   This application claims the benefit of U.S. Provisional Patent Application No. 60/410,543, filed Sep. 13, 2002, the entirety of which is hereby incorporated by reference. 

   BACKGROUND 
   1. Field of the Invention 
   The present invention is directed to cutting, engraving, or perforating products by means of relative movement between the product and an optical beam source. 
   2. Related Art 
   Current techniques for cutting and perforating flexible products such as latex rubber gloves and garments involve inefficient manual labor operations. For example, perforations can be made by including protrusions on a former and then abrading any dried latex that forms on the protrusions. 
   Other techniques, such as mechanical piercing, are limited in both their precision, accuracy, and feature size. Furthermore, manual or purely mechanical techniques can be even more difficult and time consuming if the products must first be removed from the formers on which they are made before processing. Thus, an improved method for quickly and precisely cutting, perforating, and engraving flexible products is needed. 
   SUMMARY 
   The present system provides fast, accurate, high density perforating, engraving or cutting of simply or complexly shaped products (such as latex products). A target product is positioned on a carrier (such as a body mannequin or former). The former may be made of a variety of materials such as metal (e.g. aluminum) or porcelain. The former and an optical beam (such as a focused optical beam) are moved relative to one another (either by moving the former, moving the optical beam source, moving the focus, or moving two or all of these simultaneously) so the former is in the proper position relative to the optical beam. The optical beam may then perforate, engrave, cut, or otherwise modify the product on the former. The perforations, engravings, or cuts to the product may be on any portion of the product (such as the front, back, or sides of the product). 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     Exemplary embodiments of the present invention are described herein with reference to the drawings, in which: 
       FIG. 1  is a block diagram of one embodiment of the device; 
       FIG. 2  is a side view of a laser ray, a lens and a focal plane; 
       FIG. 3  is a side view of one example of a laser gun and motors; 
       FIG. 4  is a side view of the laser ray, lens and focal plane shown in  FIG. 2  with a former in a first position and a second position; and 
       FIG. 5  is a perspective view of a medical glove on a former with a laser ray and lens. 
   

   DETAILED DESCRIPTION 
   Preferred and alternative embodiments of the subject system and method are described herein. The present invention will be described with respect to certain embodiments and drawings. It will however be apparent to the person skilled in the art that other alternatives and equivalents or embodiments of the invention or combinations thereof can be conceived and reduced to practice without departing from the proper scope of the invention as defined in the appended claims. 
   Referring to  FIG. 1 , there is shown a block diagram of the system. A controller  10  controls the operation of the system. Examples of a controller include, but are not limited to, a computer, a terminal, a workstation, or some other electronic device capable of controlling the operation of the positioning device  16  and the optical beam device  24 . The controller  10  includes a processor  12  and a memory  14 . The processor  12  may comprise a microprocessor, a microcontroller, or any device which performs arithmetic, logic or control operations. The memory  14  may include non-volatile memory devices such as a ROM, or magnetic or optical memory. The memory  14  may also include volatile memory devices such as a RAM device. Software may be included for the controller to control components within the system, such as the positioning device  16  and optical beam device  24 . 
   The controller  10  communicates with the positioning device  16 , as described in more detail below. The positioning device  16  includes at least one motor  18  for moving a former  22  (or alternatively moving the optical beam device  24  or the focus of the optical beam device  24 ). The positioning device  16  further includes at least one sensor  20  for sensing the position of the former  22  (or alternatively sensing the position of the optical beam device  24 ). In an alternate embodiment, the sensors may be located within the controller  10 . In one embodiment, the positioning device  16  may be a robotic device. 
   In order to work on the products, the products are preferably positioned on a carrier during perforation, engraving or cutting. The positioning of the product on the carrier enables the product to be given 3-Dimensional proportions (rather than merely 2-Dimensional proportions such as by laying the product flat). In one aspect, the products may be latex rubber or any other elastic or stretchable item. 
   There is thus provided an apparatus in accordance with a preferred embodiment of the present invention which may include:
     1. An optical ray source, optical beam array, split-ray source or multi-ray source.   2. A positioning device comprising a distance determiner and sensors.   3. A product carrier such as a 3-Dimensional curved former.   

   A method for perforating and cutting may be performed as follows. The former  22  carries a product, and an optical beam device  24  may be positioned relative to the former  22 . In one embodiment, the former  22  is positioned, by a positioning device  16  using motors  18 , to a process starting point where the distance and focus of the optical beam are in proper working position. The optical beam device  24  is capable of perforating, cutting or engraving the product. In an alternate embodiment, the optical beam device  24  is positioned by the positioning device  16  to a process starting point. In still an alternate embodiment, both the former  22  and the optical beam device  24  may be positioned by the positioning device  16 . In one embodiment, the former  22  may comprise a mannequin. In one embodiment, the optical beam device  24  may comprise a CO 2  laser which is suitable for cutting or perforating materials. Other types of lasers may be used. 
   The optical beam device  24  may include a variety of controllable parameters. Examples of the parameters include, but are not limited to, intensity, duration, wavelength, focus and period of time. The parameters of the optical beam may be operated in accordance with the product&#39;s characteristics such as material, color, thickness, and in accordance with perforation specifications such as depth, width, dimensions, density, shape, pattern, etc. The parameters for operation of the optical beam may be set automatically or manually. If set automatically, the parameters may be determined by accessing the memory  14  which stores the parameters for operation of the optical beam. Alternatively, the optical beam may scan the product using a sensor or sensors (such as a sensor or sensors included with the positioning device  16 ) on the former to determine aspects of the product such as material, thickness, color, etc. of the product. Based on this determination, the memory  14  may be accessed to set the parameters for the optical beam based on the aspects of the product. 
   After the first step of perforating or cutting, the positioning device  16  preferably repositions the former  22  or the optical beam device  24 , so that the new position on the former  22  is at the focus plane of the optical beam from the optical beam device  24 . In one embodiment, the positioning device  16  moves or rotates the product on the former  22  in front of the optical beam device  24  according to data received from the distance determiner (not shown) and the sensing system  20 . 
   Alternatively, the positioning device  16  moves the optical beam device  24 . In another alternative embodiment, the positioning device  16  moves both the former  22  and the optical beam device  24 . As another alternative, the positioning device  16  can move one or more focusing lenses so that a workpiece on the former  22  is substantially at the focus plane of the optical beam regardless of a change in the distance between the former  22  and the optical beam device  24 . 
   The distance between the focal plane and the product and the focal length of the ray along the process can be pre-set for all the steps of the perforating process, for instance by mechanical routine, by software, or by any other suitable method known in the art so the positioning device  16  will correct the distance and focus during its movements along the production process. 
   Alternatively, the determination and adjustment of distance and focus can be done in real-time by a measurement or sensing device, such as an optical device, ultrasonic device (for example, the one or more sensors  20  on the positioning device  16 ) or other devices known in the art, and the data can be transferred to the controller  10  and to the positioning device  16  for appropriate adjustment of the location of the former  22  in relation to the focal plane. 
   Referring to  FIG. 2 , there is shown a side view of a laser ray  26 , a lens  28  and a focal plane  30 . The laser ray  26  may be focused onto a focal point  32  in the focal plane  30  using lens  28 . Focusing the laser ray  26  allows for better cutting, engraving or perforation. The focal length  34  may vary in distance and may be defined as the distance from the lens  28  to the focal plane  30 . One example of a suitable focal length  34  distance is 100 millimeters. 
   Referring to  FIG. 3 , there is shown a side view of one example of a CO 2  laser gun  36  and motors  18 . The CO 2  laser gun  36  outputs a beam which is reflected by mirror assembly  38 , which can be, for example, an X-Y system capable of scanning the laser ray  26  in two directions. Motors  18  may drive mirrors in mirror assembly  38  in any direction, such as the x or y directions. This allows for the laser ray  26  reflected by mirror assembly  38  to make particular traces, such as a circular trace  40 , as shown in  FIG. 3 . In this manner, the laser ray  26  may be used to cut, perforate, or engrave certain shapes on the product that is on the former  22 . For example, a buttonhole may be cut by controlling the trace of the laser ray  26  so that it travels in a circular or elliptical path. Alternatively, the laser ray  26  may remain stationary and the former  22  may move so that certain shapes may be cut on the product. In still an alternate embodiment, both the laser ray  26  and the former  22  may be moved relative to one another. In one embodiment, the lens  28  is located between the mirror assembly  38  and the former  22 , although it is possible for the lens  28  to be located between the CO 2  laser gun  36  and the mirror assembly  38 . 
   Referring to  FIG. 4 , there is shown a side view of the laser ray  26 , lens  28  and focal plane  30  shown in  FIG. 2  with the former  22  in a first position and a second position. The former  22  may be in a first position, with the laser ray  26  being focused on area  1  by lens  28 . As shown, an area  1  is in the focal plane  30 . Further, the former  22  may be moved (such as by rotating and moving the former  22  in the x, y or z directions) so that a second area, such as an area  2  may be in the focal plane  30 . In this manner, different sections of the product on the former  22  may be subject to cutting, perforating, or engraving. In one embodiment, the former  22  may be moved so that the laser ray  26  is in a certain area (such as one of the areas  1 ,  2  or  3 ). Within a certain area, the laser ray  26  may be moved (such as by using the motors  18  as shown in  FIG. 3 ). In this manner, rough adjustments as to where the laser ray  26  hits the product may be performed by moving the former  22 , while fine adjustments may be performed by moving the laser ray  26  (such as by operating the mirror assembly  38 ). For example, if one seeks to create a series of small holes in a particular area, the former  22  may be moved to an area (such as the area  1 ) and the laser ray  26  may be moved to create a series of pinpoint holes (such as in a grid). 
   Referring to  FIG. 5 , there is shown a perspective view of a medical glove on the former  22  with a laser ray  26  and lens  28 . The former  22  may be connected to a robotic device (which functions as the positioning device  16 ). The connection may be made by attaching pole  44  on the former  22  to the robotic device. The former  22  may then be moved. For example, the former  22  may be dipped in a bath (such as a bath of latex liquid). The robotic device may hold former  22  within the bath for a period of time and then be withdrawn from the bath. After the latex liquid on the former  22  solidifies, the product on the former  22  may be cut, engraved, or perforated. The robotic device may move the former  22  in any direction and to any position so that the laser ray  26  may contact any portion on the former  22 . For example, to cut the opening of the medical glove (where the hand is inserted), the laser may remain stationary, focusing the laser ray  26  on an upper portion of the former  22  (for example at a point  46 ) and the robot may move the former  22  in a circular direction so that the cut can be made along the circumference of the glove. 
   The system is thus suitable for cutting, perforating or engraving non-flat surfaces, polygons, complicated 3D shapes, curved surfaces, asymmetric shapes, etc. and can be used with a wide range of target materials, such as plastics, polymers, rubber, thin polymers layers, elastomers, metals, glass, and more. 
   One example of the operation of the system is as follows. An industrial robot dips the former  22  in latex liquid, the former  22  is pulled up and the former  22  is positioned by the motors  18  of the positioning device  16  in front of the optical beam device  24  at such a distance that the focus of the laser ray  26  will be accurate and most effective (e.g., positioning the former  22  so that at least a portion of the former  22  is at the focal plane  30 ) to perforate a target area of the latex film on the former  22 . The focus of the laser ray  26  may also be adjusted to give optimal performance instead of, or in addition to changing the distance between optical beam device  24  and the former  22 . 
   The laser ray  26  may then be operated to perforate or cut the product, in accordance with the selected volume, wavelength focus and period of time and in accordance with the product&#39;s characteristics as described above. 
   The former  22  may then be rotated and repositioned by the robot, so that the next area to be perforated is facing the ray source (such as at the focal plane  30 ), at the same distance and at the same angle to the laser ray  26 . 
   If the former  22  shape is complicated, the robot may be required to make horizontal, vertical, and rotation movements, in order to bring the former  22  to the correct position in 3-Dimensional space relative to the laser. Accordingly, the robot may be required to work in any number of axes. 
   The focus may also be readjusted and a second step of the perforation may then be carried out within a very short time. These steps may be repeated, so that all the perforations and cutting required are finished in a relatively short time. 
   The movement of the former  22  in front of the laser ray  26  can be done step-by-step, or in the case of cutting, can be continuous and smooth, with all movements in all axes being done simultaneously, so that a clean cutting line will be formed. 
   It is also possible that the focus or distance of the optical laser ray  26  from the former  22  may be adjusted during the movement of the former  22 . As a result, a hole, group of holes, cuts or engraving may be created in the latex layer while the product is still on the former  22 , with no need to remove the product and put it on another device for perforating. In this manner, there is no need to remove the product (such as latex garment) from the former  22  in order to cut/perforate the product (as was done in the prior art). Rather, the cutting, perforating, or engraving may be performed on the former  22  which is used to form the latex product. 
   It should also be appreciated that this system enables very high-density perforation, where the distance between the holes and the size and shape of the holes are virtually unrestricted and the location and shape of the holes and cuts are very accurate. Further, the edge finish using this system and method is clean. 
   The method may thus be used to create perforations, in order to make aeration areas, lighted areas, patterns and designs, buttonholes, lace holes, tearing lines, etc. The method may also be used to cut a product&#39;s edges, to engrave patterns, or for any other purpose. 
   Latex products can be gloves, garments, dressings, other body related products, industrial products, or any other products. 
   Several embodiments of the present invention have been described herein. It is to be understood, however, that changes and modifications may be made in these described embodiments without departing from the true scope of the invention, which is defined by the following claims.