Abstract:
A workstation having an assembly that includes a support for holding a jamb positioned with the face thereof at a site for mortising a hinge pocket in the face, a support for receiving and holding a door with its hinge side edge at the site adjacent to and parallel with the jamb for mortising operations at that edge and a cutting tool carried by the assembly operating to form hinge mortises in an edge of the door and the jamb face at the site. The support for the door is operable to pivot the door about the hinge side edge of the door from a first angle for forming hinge mortises in the hinge edge of a door having a bevel and a second angle for forming hinge mortises in the hinge edge of a door having no bevel.

Description:
BACKGROUND OF THE INVENTION 
   This invention relates to the manufacture of door units for installation in building constructions. Doors together with their frames are typically delivered as a unit to the construction site in partial or completely prefabricated form. Such Units are referred to as “prehung” doors and they comprise a door and a doorframe, The doorframe, in turn, comprises a door jamb at either vertical side of the door and a header, the horizontal member above the door connecting the two jambs. 
   Hinges attach the door to one of the jambs (the hinge jamb) for opening and closing the door. The other vertical jamb is referred to as the strike jamb, as it receives the bolt on the door latch for closing and locking the door. Doors units are made to be either right opening or left opening, as needed. Left opening doors will have their hinges and hinge jamb on the right and right opening doors will have their hinges and hinge jamb on the left. Hinges and other door hardware will be placed accordingly 
   Two or three hinges are normally applied, spaced apart along the door side edge and jamb margin. Hinges for doors typically are butt hinges which comprise two flanges or leaves that are joined together at adjacent margins with a pin extending along the margins from the top of the flanges to the bottom to form the hinge joint. The flanges are for seating on the receiving surfaces of the door and jamb. Typically, the receiving surfaces are prepared by routing out a pocket for each flange to a depth that the outer surface of each flange is flush with the adjacent door and jamb surface. 
   The hinge flanges are each provided with holes therethrough for receiving screws to fix the hinge flanges to the door margin on one side and the jamb face on the other, with the hinge pin therebetween. When the hinge is closed, bringing the two flanges together, the hinge joint with its pin extends along one side of the hinge. The hinges are mounted with their pin sides to the same side of the door (the pin side) with the door edges seated so that the door may thus be opened toward the pin side. 
   Earlier, both of the side edges of doors had a generally flat surface that extended perpendicularly to the door face (referred to here as “square edges”). More recently manufacturers have beveled the side margin of the door on one side, the side intended to be the latch side. This bevel is typically at about three degrees inward in the direction of closing the door. This bevel is for the purpose of insuring adequate clearance between the door edge and jamb as the door is closed. However, if the door unit fabricator wishes to be able to produce units which are either left or right opening two inventories of doors must be carried, one of doors with a right side bevel and the other with a left side bevel. 
   To alleviate this problem, many door manufacturers now produce doors that are beveled on both side edges so that they may be used to produce either right or left opening doors, as desired. However, this, in turn, has created another problem in manufacturing the door units with the automatic equipment currently in use, as will be described. 
   Door units are fabricated using automated workstations, which prepare the side edge of the door and the face of a jamb for applying hinges. U.S. Pat. No. 5,222,290 of the present inventor describes one example of such a workstation. At these workstations pockets are formed in the door and door jambs for the hinges. Additionally, the workstation may have automated equipment for applying hinges on the door and door jambs at the thus prepared surfaces. The workstations are adapted to receive and hold rigidly a door, usually with the door face generally horizontally disposed, with a leading side edge of the door at a station for mortising to form hinge pockets. A door jamb is held at that location with its side edge generally parallel with the leading door side edge and with the jamb face flush with the leading side edge of the door. The jamb face and the surface of the door edge are thus essentially coplaner and thereby establish a work plane for carrying out the pocket milling operation on both the door edge and the jamb face at that location. 
   Typically, such workstations have one or more routers that may be moved to confront desired hinge sites along the adjacent door side edge and jamb face and to mill out the hinge pockets on the surface of the door side edge and on the jamb face at the work plane. The routers are oriented to mill the surfaces in a plane parallel with the work plane at the jamb face and the surface of the door side edge. In this manner pockets can be formed that receive the hinge flanges with the upper surfaces of the flanges flush with the jamb face and the door side edge surface. 
   The workstation may also have associated equipment to apply a hinge to the thus prepared hinge site at the work plane following the router operation. Screws are supplied to the screw hole sites by this equipment and automatic screwdrivers are applied to drive the screws perpendicularly to the work plane. 
   The foregoing equipment and procedure may be applied with good results to the traditional door edges that are not beveled, i.e. they are square, (perpendicular to the door faces). However, if the door edge is beveled, the hinge pocket will still be milled perpendicularly to the work plane, not parallel to the beveled surface. The result is that the hinge flange applied to the beveled edge of the door is, in turn, not parallel with the bevel. Consequently, the hinge flange will not be flush with the beveled surface, but, rather, partly exposed, above the beveled surface. This exposure detracts from the appearance of the door unit and may to some degree impair the attachment of the hinge to the door. 
   In one attempt to at least partially remedy this defect. The router is reoriented to mill at an angle that is half way between the work plane and the angle of the bevel. This compromise reduces, but does not eliminate, the exposure of the door hinge flange beyond the edge surface. And as a consequence, since milling is no longer parallel with the jamb surface, the hinge flange at the jamb face now will be partially exposed as well. 
   Another approach regarding this problem is that described in U.S. Pat. No. 6,561,238. A door processing machine is provided with a large tiltable section that bears a router for forming hinge pockets and the support structure for holding a jamb with its face in position for milling by the router. This section is supported by a single pivot bar extending the length of the machine parallel to the leading side edge of the door. If the leading edge of the door is square, the tiltable section is pivoted relatively to the door to bring the router into confrontation with that edge to mill it parallel with the surface of the door edge. With that positioning the router may mill parallel to both the surface of the door edge and the jamb face to produce the hinge pocket. If the leading door edge is beveled, the tiltable section may be pivoted to bring the router borne by it to an angle to mill the door edge surface parallel with that surface. The hinge pocket may thus be milled to a uniform depth to completely receive the hinge leaf with its surface flush with the door edge surface. Since the jamb is borne by the tiltable section, it will also tilt so its face is in confrontation with router at either positioning. 
   While with the forgoing arrangement hinge pockets parallel with the jamb face and door edge surfaces may be milled, there are significant disadvantages with this approach. It requires a radical departure from the normal workstation design. A large section of the workstation, including frame, is mounted for rotation on a single long bar. This section must not only bear the mortising assemblies but any additional equipment for operating on the juxtaposed door edge and jamb, such as a hinge applicator, including its, hinge storage and delivery equipment, screw dispenser and multiple automatic screwdrivers. Additionally this pivoting section must bear the jamb and its support equipment. Besides the complexity of this design, there can be a substantial risk that one or more of these work un-its can become misaligned due to the heavy equipment borne by this suspended section. A simpler, less expensive and more straightforward and reliable approach is needed. 
   SUMMARY OF THE INVENTION 
   This invention relates to a procedure and apparatus for automatically preparing hinge pockets in a door side edge and an adjacent jamb face that are satisfactory for hinging either a bevel edge or a square edge of a door to a door jamb. In this invention conventional equipment designed for forming hinge pockets in a square door edge and a door jamb face may be employed. Such workstations have an assembly for machining hinge pockets, including a cutting tool moveable to a workplane, the position where the tool or cutter comes into contact with the door edge, for cutting into surfaces located at the workplane to form hinge pockets that are parallel with the workplane. The cutting tool cuts in a plane parallel to the workplane and perpendicular to the forward direction of movement of the cutting tool. Normally, the cutting tool cuts a surface in a transverse routing path in its direction of travel, beginning at the workplane, for a distance equal to thickness of the hinge leaves. Such workstations have a support for holding a door with a leading side edge of the door at the workplane and another support for holding a door jamb with its side edge generally parallel with the leading door side, with the jamb face flush with the leading side edge of the door and with the jamb face and the surface of the door edge in the workplane. 
   In conventional workstations, the support for the door is fixed and presents the leading side edge of the door at the workplane with the face of the door perpendicular to the workplane. In contrast, as an important feature of this invention the support for the door is provided with the capability of tipping the door about the leading edge of the door between a position that holds the face of the door perpendicular to workplane to a position at which the beveled surface of a beveled side edge of beveled door is in the workplane. 
   In another feature of the invention, the hinge pocket routers and other equipment operating at the jamb and door edge may be fixed in positions to provide a workplane therefor that is inclined at an angle from the vertical away from the door edge, and particularly at an angle equal to the angle of the door edge bevel or greater. The support for the jamb is arranged to support the jamb with its face in the thus inclined workplane. In this configuration the door support positions the door with its face horizontal or higher for a beveled door and at a yet higher angle for a square edge door. Preferably the workplane is inclined at an angle equal to the angle of the door edge bevel and the door support supports the door to the horizontal plane. The foregoing configuration avoids the difficulty of modifying the workstation to permit positioning the door below the horizontal. 
   In another feature of this invention, the workstation further includes an automatic door hinger, comprising an applicator for receiving a hinge with its leaves open, for receiving screws in position for driving through openings in the hinge leaves and for applying, at the workplane, the hinge together with the screws, with one hinge leaf at a hinge pocket in the door edge and the other leaf at a hinge pocket in an adjacent jamb face, a screw feeder for feeding screws to the applicator individually for each opening in the hinge leaves and a battery of automatic screwdrivers oriented for driving the screws through the hinge openings into the door edge and jamb face perpendicularly to the workplane. 
   In another feature of the invention the workstation is provided with a fixed frame that supports the hinge pocket router modules, the jamb and a tilt frame that support the door with its side edge at the workplane and tilts the door between a position at one angle for a beveled door and another angle for a square edged door. 
   In another feature the tilt frame supports a latch side module for machining the latch side so that the module may machine the latch side with the door tilted at an angle for either a square edge or for a bevel edge door. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is an isometric partial view of an embodiment of the workstation of the present invention, taken from the front side of workstation at the outfeed end; 
       FIG. 2  is a is plan view of the outfeed end of the workstation of  FIG. 1  with the door support in its lowered position  1 ; 
       FIG. 2A  is a blown-up fragmentary view taken of the circular portion indicated by the connecting line of the plan view of  FIG. 2  of the workstation of  FIGS. 1 and 2  showing details of the front side of the workstation at the outfeed end; 
       FIG. 2B  is a blown-up fragmentary view taken of circular portion indicated by the connecting line of the plan view of  FIG. 2  of the workstation of FIGS.  1  and  2 ;, showing details of the rear side of the workstation at the outfeed end; 
       FIG. 2C  is a blown-up fragmentary view taken of the circular portion indicated by the connecting line of the plan view of  FIG. 2  of the workstation of  FIGS. 1 and 2  showing further details of the front side of the workstation at the outfeed end; 
       FIG. 3  is a is the same cross-sectional view as in  FIG. 2  with the door support in its elevated position; 
       FIG. 3A  is a blown-up fragmentary view taken of circular portion indicated by the connecting line of the plan view of  FIG. 3  of the workstation of  FIGS. 1 and 2  showing details as in  FIG. 2A ; 
       FIG. 3B  is a blown-up fragmentary view taken of circular portion indicated by the connecting line of the plan view of  FIG. 3  of the workstation of  FIGS. 1 and 2  showing details as in  FIG. 2B ; 
       FIG. 3C  is a blown-up fragmentary view taken of circular portion indicated by the connecting line of the plan view of  FIG. 3  of the workstation of  FIGS. 1 and 2  showing details as in  FIG. 2C ; 
       FIG. 4  is an isometric partial view of the workstation of FIG. taken from the rear side of workstation at the infeed end  1 ; 
       FIG. 5  is a plan view of the outfeed end of the workstation of  FIG. 2  showing the door support in its lowered position in bold lines and in the raised position dotted lines; 
       FIG. 6  is a plan view of the outfeed end of the workstation of  FIG. 2  showing section lines  6 A- 6 A; and 
       FIG. 7  is a is cross-sectional plan view taken along lines  6 A- 6 A of  FIG. 6 , showing pivot details. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
   The following description illustrates the manner in which the principles of the invention are applied but is not to be construed as limiting the scope of the invention. 
   The workstations of this invention are intended for preparing doors and jambs for hinging by mortising hinge pockets in both the door edge and a jamb face. They may also be used for preparing the door for application of other door hardware, including latches and bolts. For mortising the hinge pockets, mortising modules are stationed at the hinge sites along the door edge. Alternatively, a single mortising unit may be employed for all of the hinge sites, by mounting the mortising unit on a carriage that traverses the length of the door edge, stopping at each hinge site to create hinge pockets in the door edge and jamb face at that site. 
   The workstations may also advantageously incorporate automatic hingers for application of hinges in the same operation. For this purpose they may be mounted for operation at stationary site or on a carriage or the like for movement together with screw driving equipment to screw driving locations. For such a workstation, the hinger may be mounted on a carriage with associated machinery to traverse to the hinge sites along the door edge for applying hinges to doors and door jambs at those sites, as described in my U.S. Pat. No. 5,222,290. The carriage moves on rails along the door edge to hinge locations carrying the automatic hinger, including a hinge applicator, screw feeder, hinge feeder and automatic screwdrivers. 
   Referring to the drawings, particularly to  FIGS. 1 ,  2 , and  4 , a workstation  1  is shown having a frame  2  comprised of corner uprights  3  at the outfeed end, as shown in  FIG. 1 , and at the opposite (infeed) end of the workstation (shown in  FIG. 4 ) and lateral beams  4  connecting and supporting all four uprights  3 . Pivot frame  5  is comprised of beams  6  and is carried by frame  2  as follows. Referring to  FIG. 6 and 7 , pivot shaft  8  extends along, the front side  7  of workstation  1  at the inside of frame  2  and is spaced a small distance from and attached to beam  4  at side  7  by mounting bearings  9 A permit rotation of shaft  8 . At either end of front side  7  one end of a beam  6  of pivoting frame  5  is attached to mounting bearings  9 B for pivoting frame  5  about pivot shaft  8 . 
   At each rear corner of frame  5  at the back of workstation  1 , frame  5  is supported for tilting between a lower position and an elevated position by cam  10  having a rack along a horizontal upper surface. A gear wheel  11  is mounted on a projection from a beam  6  to mesh with cam  10  and be supported by cam  10 . Cam  10  has an inclined lower cam surface  12  that is borne by support wheel  13  that is rotatably mounted on a plate  14  projecting from and attached to beam  4 . Thus cam  10  is supported by support wheel  13  and, in turn, supports gear wheel  11  and thereby frame  5 . 
   When cam  10  is at its rear position the pivoting frame  5  is at its lower position bringing a door resting on top of frame  5  to a horizontal position. When cam  10  is at its forward position the pivoting frame  5  is at a raised position about its pivot at pivot shaft  8  bringing a door resting on top of frame  5  to a tilted position above the horizontal. Air cylinder  15  is secured to beam  6  at the forward end and its piston  16  is attached to the rear end of cam  10  for urging it between the rear position and the forward position. 
   Mounted on pivoting frame  5  is carriage  20  borne by a support tube  21  toward the outfeed end of workstation  1  and another support tube  21  toward the infeed end. Tubes  21  are secured to and extend from beam  6  at the back side of frame  5  to beam  6  at the front side of frame  5 , to which they are also secured. Sleeves  22  attached to carriage  20  slidably engage tubes  21  for movement of carriage  20  along tubes  21  toward and away from the front of workstation  1 . Carriage  20  bears door edge clamp member  23  as will be discussed. Carriage  20  also has a support frame  24  that includes two tubes  25  in the door feed direction. A striker side machining module  26  is slidably mounted on tubes  21  by sleeves  27  for lateral movement in the feed direction for adjusting its positioning for machining the striker side latch hole, bolt hole and latch mortise. 
   A circular pull chain  28  is provided at both the infeed and outfeed sides of carriage  20  for adjusting its position toward and away from the front side of workstation  1  to accommodate doors of different widths. Pull chains  28  are fixed to carriage  20  at respective tension control cylinders  29 , Each chain  28  is looped around a sprocket wheel  30  rotatably held by beam  6  toward the front of workstation  1  and a sprocket wheel  31  held by a beam  6  toward the rear of workstation  1 . Sprockets  30  are both fixed to rotatable shaft  8  and turn with it. When shaft  8  rotates, both chains  28  are urged in the same direction to move carriage  20  either toward or away from the front of the workstation. A motor (not shown) rotates shaft  8 . 
   Conveyor belts  35  at both the infeed and outfeed ends of the workstation are adjacent door edge clamp  23  at the rear edge of the door path through the workstation and held by slave pulleys  36  and a drive pulley  37 . Each drive pulley  37  is sidably mounted along and driven by a respective hexagonal drive shaft  38 . The respective drive shafts  38  are power interconnected through a hexagonal drive shaft  39  along the rear side of the workstation by means of transmission gears  40  at the respective junctions of drive shafts  38  and drive shaft  39 . A motor (not shown) rotates drive shaft  39  to thereby drive both conveyor belts  35 . 
   As seen particularly in  FIGS. 2A  the front side  7  of the workstation is sidewall  44 , the top portion  45  of which serves as a door edge clamp and a jamb clamp. Behind sidewall  44  are “H” shaped blocks  46  that act to reinforce and to bring sidewall  44  and clamp portion  45  to the proper angle to set the workplane for routers and other work elements operating at the workplane. H blocks  46  are tapered with a decreasing thickness toward the bottom of frame  2 . Frame  2  is rectilinear and beams  4  at the front of the workstation are in the same vertical plane. H blocks, which are attached to the front side beams  4 , are tapered by an amount to bring sidewall  44  and door edge and jamb clamp  45  to an angle from the vertical toward the front of the workstation equal to the angle of the bevel of doors to be processed on the workstation. Currently, the standard for bevel door is a three degree bevel. Thus, in this embodiment, the H blocks are tapered at a three degree angle to bring sidewall  44  and clamp member  45  to an angle of three degrees from the vertical. 
   Referring particularly to  FIGS. 1 ,  2 A,  3 A,  4  and  5 , router modules  47  are secured against the outside of sidewall  44  at hinge sites along a door edge  49  of a door  48  on the workstation. The workplanes of their cutting tools are thus parallel to sidewall  44  and at a three degree angle from the vertical. At each of these sites there is a gap in sidewall  44  and in H blocks  46  to provide clearance for operation of routers and other work equipment at those sites. As shown in phantom lines in  FIG. 5 , router modules  47  are movable between a position confronting the door edge and a position confronting the jamb face to mortise both the door edge and the jamb face. At either position they maintain their parallelism with sidewall  44  their workplane remains at three degrees from the vertical. 
   Door edge  49  is held against clamp member  45  at sidewall  44  by edge clamp member  23  acting from the latch side edge of door  48  and supported from below by edge rest  50 . 
   As seen particularly in  FIG. 2C and 3C , a jamb clamp  51  is at either end of jamb and has a piston  52  that projects to clamp the jamb  53  against the clamp member portion  45  of sidewall  44 . This brings the face  54  of jamb  53  into the workplane established by router modules  47 . The clamps  51  hold jamb at a spacing from door edge  49  appropriate to accommodate an open hinge therebetween along the work plane, with one flange at the face of the jamb and the other at the door side. 
   Uprights  56  extend vertically at both front ends of the workstation. and carry carriage track  57  extending between uprights  56 . Uprights are attached to stationary frame  2  of the workstation. Carriage  58  rides along the front of the workstation on track  57  and carries with it the automatic hinge applicator module  59 . Hinge and screw applicator  60  is suspended below carriage  58  on swing  61  that is attached to carriage  58  by a pivot connection  62 . Hinge and screw applicator swings about pivot connection  62  between a retracted position and an engaged position adjacent sidewall  44 , impelled by air cylinder  63 . Track  57  is spaced outwardly from the sidewall  44  at the front of the workstation to a position that brings pivot  62  on carriage into the same plane as the inner side of sidewall  44 . With pivot  62  so positioned hinge and screw applicator at its engaged position the face of hinge and screw applicator  60  will be parallel with sidewall  44  and in the workplane with the jamb face  54  and door edge  49  for applying a hinge. At that position the bits of automatic screwdrivers  64  carried on applicator  60  will also be perpendicular to the workplane to properly drive the screws. Screw dispenser  65  is also mounted on carriage  58  to collate screws and supply individually to applicator  60  for each screw opening in the hinge through a plastic tube from the dispenser for each (not shown). 
   Before a door is fed at the workstation infeed, if the door is a different width from that last processed, chain  28  is activated to move carriage  20  toward or away from the edge clamp  45  an appropriate distance to accommodate the new door. If the door is beveled and the last door with a square edge, or vice versa, air cylinder  15  is activated to either move the cam to the rear or forward, as appropriate. With the cam forward, the workstation is set for processing a square edge door. With the cam at its rear position, the door will be in a horizontal position for processing a door having a beveled side edge.