Abstract:
An apparatus is disclosed having a notching tool and a cutter that work together to cut perimeter contours and notch geometry along the perimeter of a work material with high precision and quality in a single pass of the cutting mechanism. The apparatus includes a rotary die that is rotatably coupled to a cutting head for movement between a working position where the cutter engages the work material and a non-working position where the cutter is positioned away from the work material. The cutter is positioned relative to a shaped die blade when both the cutter and die blade are in the working position to allow pattern pieces to be simultaneously cut and notched in response to commands issued from a controller. The apparatus is faster than conventional mechanisms used for cutting notches along work material piece perimeters since the notching and cutting operations are done in parallel.

Description:
RELATED APPLICATION  
       [0001]     This application is a continuation-in-part of U.S. patent application Ser. No. 10/627,003, filed Jul. 25, 2003, the disclosure of which is hereby incorporated by reference. 
     
    
     FIELD OF INVENTION  
       [0002]     The present invention is generally directed to cutting and creating apertures such as notches in sheet-type work material and is more specifically directed to simultaneously cutting an edge and generating notches and other shaped apertures.  
       BACKGROUND OF THE INVENTION  
       [0003]     Pattern pieces cut from layers of sheet-type work material particularly those cut from leather hides often have apertures such as holes or notches cut therein. In many instances, these notches are cut into arcuate edges of the pattern piece. Historically, cutting these notched pattern pieces involved a two step process. Generally, the notches are first cut into the work material with a punch or a cutting blade, and then the edges of the pattern piece are cut typically using a wheel type cutter. Cutting the notches, particularly if there are many, is in and of itself a labor intensive, time consuming process. Following the notching step with the subsequent step of cutting the peripheral edges further increases the time required to cut the pattern piece from the work material.  
         [0004]     Another difficulty occurs when a series of different notch patterns or differently shaped notches are required in the same pattern piece. When this occurs it is necessary to have on hand and use several different notch cutting tools as well as to properly layout the notch pattern. These steps can greatly and detrimentally affect the amount of time it takes to cut a pattern piece from the work material. In addition, because of the requirement for multiple operations, the likelihood for errors to be made increases.  
         [0005]     Based on the foregoing, it is the general object of the present invention to provide a notching and cutting apparatus that improves upon or overcomes the drawbacks of prior art devices.  
       SUMMARY OF THE INVENTION  
       [0006]     The present invention is directed in one aspect to an apparatus for cutting pattern pieces in, and creating apertures in sheet-type work material wherein the apparatus includes a frame having a support surface mounted thereon for carrying at least one layer of the work material. A carriage is coupled to the frame for movement back-and-forth there along in a first coordinate direction in response to commands issued from a controller. A cutting head is mounted to the carriage for movement back-and-forth along the carriage in a second coordinate direction generally perpendicular to the first coordinate direction. A rotary die is rotatably coupled to the cutting head with at least one cutting tool coupled thereto. The cutting tool has a shaped cutting portion corresponding to the shape of an aperture to be formed in the work material. As used herein, the term “aperture” should be broadly construed to include both holes and edge notches. The rotary die is movable between a working position wherein the at least one cutting tool engages the work material and a non-working position wherein the rotary die is positioned away from the work material. During operation when the rotary die is in the working position, shaped apertures are formed in the work material.  
         [0007]     Preferably, a cutter is coupled to the cutting head for movement between a working position wherein the cutter engages the work material and a non-working position wherein the rotary die and the cutter are positioned away from the work material. In the preferred embodiment, the cutter is positioned adjacent to the rotary die when in the working position to allow pattern pieces to be simultaneously cut and notched in response to commands issued from the controller.  
         [0008]     In the preferred embodiment of the present invention, the rotary die is coupled to an actuator that is positioned between the rotary die and the cutting head. The actuator is of a suitable type, such as, but not limited to a servo or stepper motor. The actuator selectively indexes the rotary die to position a cutting tool mounted thereon, in proximity to the work material. In addition, causing the die to roll along the work material will allow for patterns of spaced-apart apertures to be cut.  
         [0009]     In one embodiment of the present invention, the rotary die is adapted to carry a plurality of cutting tools. In addition, each of the cutting tools can be pivotally coupled to the rotary die to allow a cutting portion defined by the die to rotate into or out of position as the rotary die is indexed. The cutting tools can be configured so that each cuts the same shaped aperture or different shaped apertures or a combination thereof. A tool changer can also be provided so that during operation different cutting tools can be loaded onto or removed from the rotary die.  
         [0010]     In another embodiment of the invention, the cutting head comprises an outer housing and an inner housing. A first drive means, rigidly attached to the outer housing, is rotatably coupled to the inner housing, allowing the inner housing to rotate without restriction through 360° while the first drive means and outer housing remain stationary and rigidly attached to the carriage. Specifically, the rotary die and cutter are rotatably coupled to the inner housing and can be moved to an origin position on the work material by controllably rotating the inner housing using a horizontal drive means. Alternatively, a rotary fitting rigidly attached to the cutting head can also be used to provide unrestricted rotation of the rotary die and the cutter through 360°. Detection of an origin position on the work material can be accomplished using a one-to-one ratio between the horizontal drive means and the inner housing or using, in conjunction with the horizontal drive means, a sensor providing an index pulse that corresponds to the origin position. Similarly, moving the cutting tool to an origin position on the work material may be accomplished using a one-to-one ratio between the first drive means and the rotary die or using, in conjunction with the first drive means, a sensor providing an index pulse that corresponds to the origin positions.  
         [0011]     In another form of the present invention, a shaped die blade is coupled to the cutting head and has a shaped cutting portion corresponding to the shape of an aperture to be formed in the work material. The shaped die blade is movable between a working position wherein the shaped die blade engages the work material and a non-working position wherein the shaped die blade is positioned away from the work material. The movement of the shaped die blade between working and non-working positions is linear. In addition, the cutter is positioned in precise alignment with the shaped die blade when each is in working position, thereby allowing pattern pieces to be simultaneously cut and notched in response to commands issued from the controller.  
         [0012]     An advantage of the present invention is that the process of cutting apertures into the work material in predetermined patterns can be performed quickly and automatically.  
         [0013]     Another advantage of the present invention is that a pattern piece can be simultaneously notched and the edges cut.  
         [0014]     These aspects and other objects, features and advantages of the invention are described in the following Detailed Description, which is to be read in conjunction with the accompanying drawings.  
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0015]      FIG. 1  is a partial schematic illustration of a cutting table incorporating the present invention.  
         [0016]      FIG. 2  schematically illustrates a rotary die coupled to a cutting head forming part of the cutting table of  FIG. 1 .  
         [0017]      FIG. 3  is a front elevational view of an embodiment of a rotary die without a cutting tool mounted thereon.  
         [0018]      FIG. 4  is a side elevational view of the rotary die of  FIG. 3 .  
         [0019]      FIG. 5  is a perspective view of an embodiment of one type of cutting tool mountable on the rotary die of  FIG. 3 .  
         [0020]      FIG. 6  is a partial schematic illustration of a multiple cutting tool attached to the rotary die.  
         [0021]      FIG. 7  schematically illustrates a rotary die, an edge cutting tool and a tool changer.  
         [0022]      FIG. 8  schematically illustrates a rotary die and an edge cutting tool.  
         [0023]      FIG. 9  schematically illustrates a rotary die and an edge cutting tool coupled to a cutting head forming part of the cutting table of  FIG. 1 .  
         [0024]      FIG. 10  is a front view of an embodiment of the invention that includes a rotary die.  
         [0025]      FIG. 11  is a cross-sectional view of the embodiment of  FIG. 10  taken along line  1 - 1  of  FIG. 10 .  
         [0026]      FIG. 12  is a cross-sectional view illustrating a cutting head with a first drive means rigidly attached to an outer housing and rotatably coupled with an inner housing.  
         [0027]      FIG. 13  is an alternative embodiment to  FIG. 12 , illustrating a rotary fitting rigidly attached to the cutting head.  
         [0028]      FIG. 14  is a cross-sectional view of the wheel knife assembly as shown in  FIG. 13 .  
         [0029]      FIG. 15  is a front view of an embodiment of the invention that includes a shaped die blade. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0030]     As shown in  FIG. 1 , a cutting table generally designated by the reference number  10 , includes a frame  12  and work material support surface  14  adapted to carry at least one layer of sheet-type work material  16 , such as, but not limited to leather or vinyl thereon. A carriage  18  is coupled to the frame for movement back-and-forth in a first direction as indicated by the arrows labeled “X.” A cutting head  20  is mounted on the carriage  18  and is movable back-and-forth therealong in a second direction as indicated by the arrows labeled “Y.” Both the carriage  18  and the cutting head  20  move in response to commands issued from a controller  21 . As will be explained in detail below, a pair of cutting tools, each for performing a different type of cutting operation, are mounted to the cutting head  20 . The cutting tools are movable between a working position, wherein they engage the work material  16 , and a non-working position wherein they are lifted off of the work material.  
         [0031]     As shown schematically in  FIG. 2 , the cutting head  20  includes a suitable drive, such as motor  26  coupled to a housing  28 . The motor  26  may be a servo motor, stepper motor or the like. The housing  28  is rotatable about an axis designated by the reference number  29  by the stepper motor  26 . The axis  29  is generally perpendicular to the axis  31  about which the rotary die  30  rotates. A rotary die  30  having at least one cutting tool  32  mounted thereon is rotatably coupled to the housing  28  and is driven by suitable means, such as, but not limited to a second stepper motor  34 . An actuator  36  shown in the illustrated embodiment as a pneumatic cylinder is mounted to the cutting head  20  and coupled to the housing  28  to move the housing between the working and non-working positions. While first and second servo motors or stepper motors,  26  and  34  respectively, have been shown and described, the present invention is not limited in this regard as other types of actuators known to those skilled in the pertinent art to which the present invention pertains, such as servos, can be substituted without departing from the broader aspects of the invention. The same is true for the pneumatic cylinder, other types of actuators such as stepper motors, servos, or hydraulic cylinders can be substituted.  
         [0032]     As shown in  FIGS. 3-5 , the rotary die  30  includes a recessed section  38  into which a cutting tool  40  is mounted. The cutting tool  40  defines an aperture  42  extending therethrough. A fastener not shown extends through the aperture  42  and threadably engages a tapped hole  44  defined by the rotary die  30 . While a fastener extending through the aperture  42  and engaging the tapped hole  44  has been described, the present invention is not limited in this regard as other mounting means, such as a taper lock, ball and detent, or snap fit can be employed without departing from the broader aspects of the present invention. In addition, while a cutting tool  40  has been shown and described, the present invention is not limited in this regard as other types of tools such as a punch can be substituted without departing from the broader aspects of the present invention.  
         [0033]     During operation, and in response to command signals issued from the controller  21 , the rotary die  30  is moved to a position where a notch or aperture is to be cut, the rotary die is indexed to position the cutting tool  32  over the work material  16 . The cutting tool  32  is then brought into engagement with the work material  16  and a notch or other shaped aperture is cut.  
         [0034]     As shown in  FIG. 6 , the rotary die  30  can be configured to accommodate multiple cutting tools  32 . In the illustrated embodiment four tool holders  46  are mounted for pivotal movement about a pivot axis  48 . The tool holders  46  move to the rotated position (shown in dotted lines) when the rotary die  30  is rotated in the direction indicated by the arrow labeled “A.” When the rotary die  30  is rotated in the direction labeled “B”, generally opposite the “A” direction, the tool holder  46  closest to the work material moves into cutting position so that a cutting tool mounted thereon can be employed. While the directions “A” and “B” are shown in the illustrated embodiment as counter-clockwise and clockwise respectively, the present invention is not limited in this regard as the tool holders  46  can be configured to function opposite to the above-described manner.  
         [0035]     As shown schematically in  FIG. 7 , the present invention can also incorporate a tool changer  50  for storing several different cutting tools. During operation, when a different, or new cutting tool is required, the actuator  52  moves the rotary die  30  to the tool changer  50  where a mounted cutting tool is removed and stored, and a new or different cutting tool is installed. Also shown in  FIG. 7  is a cutter  54  for cutting along pattern edges. In general the cutter  54  is round having a sharpened edge and is rotatable about an axis  55  that is generally coaxial with the axis  31  about which the rotary die  30  is rotatable. Both the rotary die and the cutter wheel are mountable via rotation of the housing  28 , by the stepper motor  26 , about the axis  29 . During operation the cutter  54 , in response to commands issued from the controller  21  engages the work material and is dragged via the movement of the carriage  18  and cutting head  20  along a cutting path. The actuator  56  moves the cutter  54  between the working and non-working positions.  
         [0036]     As shown schematically in  FIGS. 8 and 9 , the cutter  54  is positioned proximate the rotary die  30  so that during operation a continuous cut along a desired line of cut can be made while simultaneously cutting notches or other shaped apertures in the work material. This has the advantage of increasing throughput over prior art machines wherein notching and cutting are usually done as separate operations.  
         [0037]      FIGS. 10 and 11  show an embodiment of the present invention that includes a rotary die  30  and cutter  54 , whereby a motor  59  provides for the rotation of the rotary die  30 . The motor  59  may be a servo motor, DC motor or the like.  
         [0038]     In accordance with another aspect of the invention,  FIG. 12  shows an embodiment whereby the cutting head  20  is comprised of an outer housing  60  and inner housing  62 . A first drive means  64  is rigidly attached to the top of the outer housing  60  and positioned vertically such that at least a portion of the first drive means  64  is contained inside the outer housing  60 . The inner housing  62  is rotatably coupled to the first drive means  64  by a first rotational coupling  65  and a second rotational coupling  66 . As a result, the inner housing  62  is able to rotate through 360° about a rotational axis labeled “C” so as not to be restricted by sensor output wire  61  and motor power and feedback wires  63 . A horizontal drive means  68  rigidly attached to the outer housing  60 , and in conjunction with a first timing pulley  69 , first timing belt  70  and second timing pulley  71 , controls the rotation of the inner housing  62  about the first drive means  64 .  
         [0039]      FIG. 12  also shows the rotary die  30  and cutter  54  rotatably coupled to the inner housing  62  by a third rotational coupling  78  and fourth rotational coupling  79 , respectively. The rotary die  30  is rotatable about a first rotational axis  80  generally perpendicular to the rotational C-axis about which the inner housing  62  rotates. The cutter  54  rotates about a second rotational axis  81  approximately coaxial with the first rotational axis  80 . The rotary die  30  has at least one cutting tool  72  mounted thereon and is driven by the first drive means  64 , in conjunction with first bevel gear  73 , second bevel gear  74 , axle  75 , third timing pulley  67 , second timing belt  76  and fourth timing pulley  77 . The axle  75  is coupled to the inner housing  62  by a fifth rotational coupling  82  and sixth rotational coupling  83 . While a servomotor is shown in  FIG. 12 , the present invention is not limited in this regard as other types of drive means known to those skilled in the pertinent art to which the present invention pertains, such as servos, can be substituted without departing from the broader aspects of the invention.  
         [0040]     Moreover, the embodiment in  FIG. 12  provides for the rotary die  30  and cutter  54  to be moved to origin positions on the work material prior to the start of, or during, operation. Specifically, controlled rotation of the inner housing  62  by the horizontal drive means  68  in response to command signals from the controller  21  allows for the rotary die  30  and cutter  54  to be precisely aligned tangent to an edge of the work material. Detection of such origin position on the work material can be accomplished using a one-to-one ratio between the first timing pulley  69  and the second timing pulley  71  and employing a horizontal drive means  68  with positional feedback that includes an index pulse. In particular, a one-to-one ratio, whereby one turn of the horizontal drive means  68  equals one turn of the inner housing  62 , will generate one index pulse for each revolution of the inner housing  62 , wherein the index pulse corresponds to an origin position. If the ratio is not one-to-one, a sensor  84  can be used to indicate which index pulse corresponds to the origin position. For example, if the ratio is four to one, whereby four turns of the horizontal drive means  68  equal one turn of the inner housing  62 , then four index pulses are generated for each revolution of the inner housing  62 . With such a ratio an ambiguity results as to which index pulse corresponds to an origin position. The sensor  84  provides additional feedback telling the index pulse in a sequence that corresponds to an origin position. The sensor  84  may register a reflective portion of the first timing belt  70  that overlaps the correct index pulse. The sensor  84  may also be a switch that registers a raised surface or detent on a portion of the first timing belt  70  that overlaps the correct index pulse. Similarly, the cutting tool  72  can be moved to an origin position on the work material using a one-to-one ratio or employing a sensor  85  as detailed above.  
         [0041]     Cross-sectional view  FIG. 13  shows an alternative embodiment to  FIG. 12 , whereby a rotary interconnect  86  provides for the rotation of the housing  28  about the rotational C-axis of through 360° so as not to be restricted by wires  87 . Also shown in  FIG. 13  is a cutter assembly, which is shown in more detail in  FIG. 14 .  
         [0042]     As shown in  FIG. 15 , the present invention can also be configured with a shaped die blade  90  that cuts apertures in the work material through linear movement. The shaped die blade  90  is coupled to a blade holder  92 , which may be hinged in such a fashion as to allow controlled deflection of the tool during continuous motion around the perimeter contour to achieve minimal disturbances of the work material. The blade holder  92  is attached to a linear actuation device  94  via a connecting shaft  96 . The linear actuation device  94  is mounted to a tool holder  98  and moves the shape die blade  90  between a working position wherein the shaped die blade  90  engages the work material and a non-working position wherein the shaped die blade  90  is positioned away from the work material. It has been found that a linear motor, servo motor and cam or pneumatic cylinder with a piston function particularly well as linear actuation devices. It will appreciated, however, that other drive mechanisms providing for linear extension may also perform sufficiently and achieve the objectives of the invention. During operation, the linear actuation device  94  is actuated in a controlled manner at the required and moves the shaped die blade  90  into working proximity of the work material through linear extension of the connecting shaft  96  and blade holder  92 . After an aperture is cut, the linear actuation device returns the shaped die blade  90 , via the blade holder  92  and connecting shaft  96  to its retracted position until the next command.  
         [0043]     Also shown in  FIG. 15  is a cutter  91 , which is round having a sharpened edge and rotatable about an axis  93 . The cutter  91  and shaped die blade  90  are fixed in position relative to each other so as to share a common rotational C-axis and also provide simultaneous aperture cutting and perimeter contour cutting. The tool holder  98  can be raised and lowered in the Z-axis as required and can also be rotated around the rotational C-axis as required. Cutting of external apertures with this embodiment would require a reversed direction of perimeter cutting and that the cutter  91  be momentarily removed from working proximity of the work material at the controlled time with a Z-axis movement in order to create a break in the perimeter contour.  
         [0044]     Certain modifications and improvements will occur to those skilled in the art upon a reading of the foregoing description. It should be understood that all such modifications and improvements have been deleted herein for the sake of conciseness and readability but are properly within the scope of the following claims.