Abstract:
A molding system to form a decorative use in a single pass and having a horizontal profile cutter, a first vertical cutter disposed adjacent an end of the horizontal cutter, a second vertical cutter secured to a hinged door by means of an extension, and the extension partially disposed in a recess formed on the adjacent end of the horizontal cutter.

Description:
BACKGROUND OF THE INVENTION 
     In the production of curved door and window arches, it is necessary to cut the inner and outer surfaces of the arch as well as the decorative face or profile of the arch. Historically these cuts have been made by means of successive separate cutting operations in order to achieve the completed arch design. Of course, this means of cutting an arch is quite time consuming and labor intensive. 
     BRIEF SUMMARY OF THE INVENTION 
     By this invention, a single pass radius molding system is provided for a decorative arch. A pair of vertically disposed cutters are provided to cut the inner and outer surfaces of the arch and a horizontally disposed cutter is positioned between the two vertical cutters to cut the profile of the arch. A recess is formed in the inner end of the horizontal profile cutter with the inner vertical cutter rotatably positioned on an extension secured to a door hinged to the frame. To provide stability, the free end of the extension is disposed in the recessed end of the horizontal cutter during a cutting operation. 
    
    
     BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
     FIG. 1 is a perspective view of the cutting machine according to this invention; 
     FIG. 2 is an enlarged perspective view of the rear cutting shaft; 
     FIG. 3 is an enlarged perspective view showing the radius setting of the machine; 
     FIG. 4 is an enlarged perspective view of the inner vertical cutter and the horizontal profile cutter; 
     FIG. 5 is a top plan view of the cutting operation; 
     FIG. 6 is an enlarged perspective view from below; 
     FIG. 7 shows a finished arch; 
     FIG. 8 is an elevational view taken along the line  8 — 8  in FIG. 7; 
     FIG. 9 is an enlarged elevational view of the inner cutter shaft assembly; and 
     FIG. 10 is an enlarged perspective view of the inner cutter. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     In the drawings, and with particular reference to FIG. 1, the numeral  1  designates multiple horizontal and vertical beams interconnected to form a frame for the molding system. Working surface  2  is supported on frame  1  and backboard  3  is joined to the rear edge of working surface  2  and extends vertically upward therefrom. Backboard  3  acts as attachment means for certain elements of the molding system. 
     For the purpose of reducing vibration in the molding process and as shown in FIG. 2, rollers  4  and  5  are provided and, in order to accommodate various thicknesses in the workpieces, are vertically adjustable by means of adjustment assemblies  6  and  7 . Adjustment assemblies  6  and  7  are secured to backboard  3  by any suitable means. 
     In order to cut a decorative arch shape in workpiece  11 , three molding cutters are utilized. More specifically, molding cutter  12  is provided for the purpose of cutting the outside vertical surface of the arch. Molding cutter  12  is adjustable in the vertical direction by means of threaded adjustment device  13  and horizontally by means of adjustment device  13   a  both of which are rotated in either direction, respectfully, by means of cranks  14  and  14   a  to cause cutter  12  to be raised or lowered and maneuvered in or out. Operational rotation of molding cutter  12  is achieved by means of motor  15  which rotates pulley and belt assembly  16 . 
     Cutter  12  can be utilized for either the inside or outside cut of the arch. For purposes of the outside cut, threads holding the cutter in the end of the shaft must be left-handed or of a clockwise configuration. The rotation of the shaft and cutter must be counterclockwise which allows the cut of the arch to be smooth and keeps the bit tight in the taper of the shaft. When utilizing cutter  12  for the inside cut of the arch, the threads for holding the cutter in the shaft must be right-handed and the cutting rotation of the shaft and cutter must be [left-handed or] clockwise also to obtain a smooth cut and keep the bit tight in the taper of the shaft. 
     When cutter  12  is not utilized for the inner cut, the inner vertical surface of the arch is machined by means of molding cutter  17  which is rotatably mounted on [hinged] door  18  which is hinged to frame  1 , as shown in FIG.  4 . The decorative profile cut is achieved by means of molding cutter  20  which is specially designed with a point zero shaving blade and cutting edges on both sides and the tip. Molding cutter  20  is rotatably mounted on shaft  21  and secured thereto by means of bolt  22  which is affixed through plate  23  to shaft  21 . 
     In alternative arrangement, cutter  12   a , as shown in FIG. 4, allows the outside edge to be cut in place of using cutter  12 . Shaving cutter  12   a  rotates in a horizontal disposition and allows the cut to begin as the arch passes through the cuter whereby the back of the arch is shaved to a 90 degree angle. Both sides have cutting edges so as to relieve heat buildup in cutter  12   a . The cutting edges of cutter  12   a  should end just below working surface  2  which allows a complete 90 degree dead center cut of the arch. Further, cutter  12   a  is removable to allow the arch to be reversed to allow adjustment between profile cutter  20 , cutter  12  and the outside of the arch. When reversing the arch, if cutter  12   a  is not removed, it will cut out the profile of the inside of the reversed arch. Shaft  21  is not adjustable which allows for complete changing of cutters of different profiles thereby reducing setup time. The adjustment is built into the radius of each profile cutter which, in turn, allows for later duplication of a particular profile. 
     As cutter  17  cuts through the arch, it overlaps the cutting tip of cutter  20  when cutter  20  begins the profile cut and cutter  17  acts to finish the profile cut started by cutter  20 . This is necessary because in order to have a tip long enough to complete the profile cut by cutter  20  when the arch is small, cutter  20  will cut the inside of the arch and cut into the profile. Also, cutter  17  has sloped side cutting edges to relieve the chopping action and maintain a shaving action to relieve the impact of the cutting forces. 
     In the molding operation of a decorative arch, the three molding cutters  12 ,  17  and  20  are of necessity quite close together and the constant vibration of the machine can cause a catastrophic failure when the molding cutters come into contact with each other. In order to prevent molding cutters  17  and  20  from coming into contact, molding cutter  20  is provided with recessed cavity  24  at one end thereof. Further, molding cutter  17  is secured to hinged door  18  by means of tapered extension  25  which is integrally attached to hinged door  18 . Therefore, prior to the molding operation, hinged door  18  is closed whereby the free end of extension  25  enters recessed cavity  24  and comes into near contact with bolt  22 . By this means, cutters  17  and  20  are disposed in close proximity and any relative movement between molding cutter  17  and molding cutter  20  is prevented since extension  25  is essentially locked in place in cavity  24 . By this means, the molding cutters can be operated at extremely high rpm&#39;s without any danger of touching. 
     After hinged door  18  is swung into the operating position, it is held in place by means of locking rod  28 , a portion of which extends through aperture  29  formed in plate  30  which is secured to hinged door  18 . Finally, locking rod  28  is threaded into threaded aperture  31 . Excess sawdust is removed from the work area by means of vacuum duct  32 . As shown in FIG. 6, cutter  17  is rotated by means of motor  33  through shaft  34 . 
     It is known that router cutters must be run at high rpm&#39;s to achieve smooth cuts. If sealed bearings are utilized, the life thereof is very short and, if unsealed bearings with dust shields and an oil mister are utilized, the life is also short due to dust interfering with the operation of the bearings. By running bearings in an oil bath, the speed will cause the bearings to clean themselves thus causing failure. 
     According to this invention, oil is forced through the bearings, which are unsealed, with a high pressure pump circulating the oil through the bearing and back into a reservoir. This allows for necessary cooling thereby yielding longer bearing life. By using a motor and cutting system and a small cutter shaft, both increased power and high speed rotation of the cutters  12  and  17  are achieved which are not possible with a router motor. 
     In operation, workpiece  11  is clamped into position by means of clamping piston  26  on horizontally movable rail  27  which is slidable on flange  1   a  of beam  1   b . Then workpiece  11  is moved into the desired cutting position on rail  27  to a position on top of working surface  2  and in proximity to cutters  12 ,  17  and  20 . Then hinged door  18  closed and, if molding cutter  12  is used rather than cutter  12   a , it is lowered into its cutting position. Following this, workpiece  11  is swung through the cutters at pivot point  26  resulting in the finished product as shown in FIGS. 7 and 8. 
     An alternative arrangement is depicted in FIGS. 9 and 10 wherein extension  25  is bolted to hinged door  18  through holes  35  and  36  in known manner. Door  18  is provided with lubrication channels  37 ,  38  and  39  which cooperate with corresponding channels disposed in extension  25 . In the arrangement of FIGS. 9 and 10, cutter  17  is disposed above extension  25  by means of shaft  40  which in turn is rotated by means of drive belt  41 . In FIG. 10, collar  42  is pressed onto and strengthens the end of shaft  43  and cutter  17  is mounted in the end of shaft  43 . 
     Therefore, by this invention, decorative arches are cut in a high-speed operation with a single pass required in the cutting operation and any chance of the molding cutters actually touching each other is prevented.