Abstract:
A combination canting and profiling apparatus includes a cutter assembly, including a profiler and a canter, supported by a support frame for movement in unison with the support frame. The profiler and the canter each have first and second cutter heads respectively rotatable about first and second axes and positioned at work piece profiling and canting stations along a workpiece feed path next to one another without any workpiece drivers therebetween. The profiler and the canter can be mounted to the support frame for movement relative to one another along a lateral positioning path oriented generally perpendicular to the workpiece feed path. Structure can also be included to facilitate curve sawing. In some examples motors driving the cutters can be arranged for load sharing.

Description:
CROSS-REFERENCE TO OTHER APPLICATIONS 
       [0001]    This application claims the benefit of U.S. provisional patent application No. 62/009,053 filed 6 Jun. 2014. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    This invention is for an improved method and apparatus for milling timber in a lumber mill. 
         [0003]      FIGS. 1 and 2  illustrate one common way of how a log is transformed into lumber. In this example gang saws can be used to make parallel cuts  10  along the length of log  12  to create the cant  14  having flat, parallel upper and lower surfaces  16 ,  18 , waste wane pieces  20  and unfinished boards  22 . The rough edges of the unfinished boards are trimmed at trim lines  23  to create the finished boards. Cant  14  is then processed by a canter  24  and a profiler  26 . The canter/profiler assembly shown in  FIG. 2  has feed modules  27  for supporting and driving the cant  14  through both canter  24  and profiler  26 . Feed modules commonly include upper and lower rollers which support and drive the workpiece through the canter and profiler. Canter  24  and profiler  26  commonly use milling cutting heads to chip away the material at canter regions  28  and profiler regions  30  on either side of cant  14 . This creates a processed workpiece  32  having side faces  34  created by canter  24  and side board profiles  36  created by profiler  26 . As indicated in  FIG. 1 , processed workpiece  32  can be cut into lumber at a downstream gang saw station. In some cases instead of a cant  14 , a log  12  with no finished faces is processed by the canter and the profiler. 
         [0004]    Canting and profiling a log or cant with today&#39;s machinery commonly uses a large diameter (typically 30 plus inches in diameter) milling tool for the canting tools and large diameter (typically 15 inch to 22 inch diameter) profiling tools.  FIG. 2  illustrates a typical arrangement for canting and profiling a log or cant, sometimes referred to as the workpiece. The large diameter tools commonly used prevent the close nesting of the milling tools and require feed modules between the canter and profiler. The length  38  of a typical canter/profiler today, measured from the beginning of the canter to the end of the profiler in the example of  FIG. 2 , is at least 90 inches long and some are as much as 120 inches long. The length of the existing canter/profilers limit the number of sawmills that can fit one into place adjacent to existing saws and increases cost due to the necessary additional space and feeding equipment. 
       BRIEF SUMMARY OF THE INVENTION 
       [0005]    The present technology can reduce the space requirement for the machinery by a factor of up to four. In some examples the distance from the beginning of the canter to the end of the profiler is less than 30 inches. The present technology addresses the space issue by tightly nesting the cutting tools and using a unique drive system. This can make the installation and operation of the equipment more cost effective and efficient for the end user. In addition, the present technology is very accurate due to the close proximity of the canter and profiler cutter heads. This close spacing eliminates any transport error between the canter and the profiler and also eliminates errors caused by the stress relieving of the cant as the sides are chipped off. The fact that all the cutting tools are mounted on the same support frame, in examples the support frame being subject to lateral shifting, vertical shifting and pivoting about a common vertical axis, greatly enhances the accuracy of the process by eliminating following errors between the canter and profiler systems. In a conventional system, the canter and profiler cutter heads can be separated by as much as 8 feet and will commonly have their own lateral shifting, vertical lifting and pivoting about a pivot axis that are independent and subject to large following errors in the motion control systems. 
         [0006]    Some examples are directed to a log or cant milling machine that opens the face of the cant or log with twin counter rotating milling tools and immediately mills a profile of the side board on the side of the cant or log with twin counter rotating and adjustable milling tools. The milling tools used are smaller in diameter than any existing milling tools currently used in the industry for canting and profiling log or cants. The milling tools can be driven to a gearbox with a combination of spiral bevel and helical gears. The small diameter (typically 10″ to 12″) milling heads and the unique drive arrangement of spiral bevel and helical gears allows the canter/profiler to be incorporated into a very small space both length wise (along the workpiece feed path) and width wise (perpendicular to the workpiece feed path). This very short length also improves the accuracy of the profile cuts on the log or cant. In conventional canter/profilers, the canter is mounted several feet in front of the profiler allowing for the log or cant to move out of position or deflect due to stress relieving and warping of the log or cant due to the material removal by the canter milling tools. With the present technology the workpieces never passed off between the canter and the profiler stations thus eliminating cutting inaccuracies present with conventional canter/profilers. 
         [0007]    A combination canting and profiling apparatus includes a cutter assembly supported by a support frame for movement in unison with the support frame. The cutter assembly includes profiler and a canter. The profiler comprises first and second, spaced apart, profiler cutter heads mounted for rotation about first and second profiler axes and positioned at a work piece profiling station along a workpiece feed path. The canter comprises a canter cutter head mounted for rotation about a canter axis and positioned at a work piece canting station along the workpiece feed path. The work piece profiling station and the work piece canting station are next to one another. 
         [0008]    The combination canting and profiling apparatus can include one or more the following. The first and second profiler axes can be parallel to one another and can be parallel to the canter axis. The canter can include first and second canter cutter heads mounted for rotation about first and second canter axes. The profiler and the canter can be mounted to the support frame for movement relative to one another along a lateral positioning path oriented generally perpendicular to the workpiece feed path. The distance between the centers of the profiler and the canter can be no more than 24 inches, with the centers defined by the profiler axes and the canter axis. A region between the profiling station and the canting station can be free of any workpiece drivers. 
         [0009]    Examples of the combination canting and profiling apparatus can also include a base frame, a carriage, and a profiler cutter heads mounting assembly. The carriage can support the support frame, and the cutter assembly therewith, on the base frame. The carriage can include a lateral slide assembly and a vertical lift assembly. The lateral slide assembly is slideably mounted to the base frame by which a position of the support frame in a lateral direction generally perpendicular to the workpiece feed path can be changed during use. The vertical lift assembly is movably mounted to the lateral slide assembly by which a vertical position of the support frame can be changed during use. The profiler cutter heads mounting assembly can mount the first and second profiler cutter heads to the support frame at different separations so that a distance between the first and second profiler cutter heads can be changed during use. In some examples the profiler cutter heads mounting assembly changes the distance between the first and second profiler cutter heads in equal amounts relative to the workpiece feed path. To facilitate curve sawing, the carriage can further include a main pivot housing, mounted to a chosen one of the lateral slide assembly and the vertical lift assembly, rotationally supporting the support frame by which a rotary orientation of the support frame about a first axis can be changed, the first axis being spaced apart from and generally perpendicular to the workpiece feed path. The cutter assembly can include a pivot housing by which a rotary orientation of a chosen one of the profiler and the canter about a second axis can be changed relative to the other of the profiler and the canter, the second axis being parallel to the first axis. 
         [0010]    In some examples the canter can include first and second canter cutter heads mounted for rotation about first and second canter axes and the motor assembly can include driveshafts with the profiler cutter heads and the canter cutter heads drivenly coupled to driveshafts of the motor assembly. The motor assembly can include a ganged motor assembly comprising at least three motors with driveshafts drivingly and drivenly coupled to one another to provide load sharing among the motors. The canter can include first and second canter cutter heads mounted for rotation about first and second canter axes and the motor assembly can include first, second, third and fourth motors. The first and second profiler cutter heads can be connected to driveshafts of the first and second motors. The first and second canter cutter heads can be connected to driveshafts of the third and fourth motors. The third and fourth motors can be drivingly and drivenly coupled to one another to facilitate load sharing. The ganged motor assembly can include fifth and sixth motors, the third, fourth, fifth and sixth motors directly coupled to one another by gears mounted to driveshafts of said motors, whereby the driveshafts of the fifth and sixth motors aid the rotation of the driveshafts of the third and fourth motors thereby facilitating load sharing. 
         [0011]    Other features, aspects and advantages of the present invention can be seen on review the drawings, the detailed description, and the claims which follow. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0012]      FIG. 1  schematically illustrates a series of steps by which a log can be transformed into lumber. 
           [0013]      FIG. 2  is a schematic illustration showing feed modules on either side of and between canter and profiler stations of a conventional canter/profiler system. 
           [0014]      FIG. 3  is a perspective view of a combination canting and profiling apparatus shown together with a partially processed cant. 
           [0015]      FIG. 3A  is a perspective view showing the partially processed cant of  FIG. 3 . 
           [0016]      FIG. 4  is a second perspective view of the combination canting and profiling apparatus of  FIG. 3 . 
           [0017]      FIG. 5  is a third perspective view of the combination canting and profiling apparatus of  FIG. 3 . 
           [0018]      FIG. 6  is a top plan view showing the profiler and canter of the assembly of  FIGS. 3-5  with the profiler and canter axes not rotationally offset and the outer edges of the profiler and canter cutter heads aligned. 
           [0019]      FIG. 7  is a view similar to that of  FIG. 6  but with the canter and the canter motor assembly moved to the left in  FIG. 7  so that the outer edges of the profiler and canter cutter heads are offset. 
           [0020]      FIG. 8  shows the structure of  FIG. 7  but with the cutter assembly rotationally offset 6° counterclockwise about a vertical axis. 
           [0021]      FIG. 9  shows the structure of  FIG. 8  after the canter has been rotated clockwise 2° about a vertical axis. 
           [0022]      FIG. 10  is a simplified overall view of a second example of a canting and profiling apparatus. 
           [0023]      FIGS. 11 and 12  are perspective views of portions of a third example of a canting and profiling apparatus. 
       
    
    
     DETAILED DESCRIPTION 
       [0024]    The following description will typically be with reference to specific structural embodiments and methods. It is to be understood that there is no intention to limit the invention to the specifically disclosed embodiments and methods but that the invention may be practiced using other features, elements, methods and embodiments. Preferred embodiments are described to illustrate the present invention, not to limit its scope, which is defined by the claims. Those of ordinary skill in the art will recognize a variety of equivalent variations on the description that follows. Unless otherwise stated, in this application specified relationships, such as parallel to, aligned with, or in the same plane as, mean that the specified relationships are within limitations of manufacturing processes and within manufacturing variations. When components are described as being coupled, connected, being in contact or contacting one another, they need not be physically directly touching one another unless specifically described as such. Like elements in various embodiments are commonly referred to with like reference numerals. 
         [0025]    In this application the terms horizontal and vertical may be used with reference to referenced items in particular embodiments. However, these terms are used in the aid understanding and not to limit the invention. In some cases the terms perpendicular or parallel may be used; they are intended to cover situations in which the referenced items are perpendicular or parallel within limitations of manufacturing processes and within manufacturing variations. When the terms generally perpendicular or generally parallel are used, these are intended to cover situations in which the referenced items are generally perpendicular or generally parallel within 10°, and preferably within 8°, and more preferably within 6°. 
         [0026]      FIGS. 3-5  are overall views of one example of a combination canting and profiling apparatus  40 . Apparatus  40  includes a support frame  42  and a cutter assembly  44  mounted to and supported by the support frame for movement in unison with the support frame. Cutter assembly  44  includes a profiler  46  at a workpiece profiling station and a canter  48  at a workpiece canting station. In a sawmill setting, with the exception of lateral side plate  98 , the mirror image of the structure shown in  FIGS. 3-5  would be duplicated to process both sides of the workpiece. 
         [0027]    Profiler  46  includes a first, top profiler cutter head  50  and a second, bottom profiler cutter head  52 , cutter heads  50 ,  52  mounted for rotation about first and second profiler axes  54 ,  56 , respectively. Apparatus  40  also includes a motor assembly  58  including a profiler motor assembly  60  and a canter motor assembly  62  both mounted to support frame  42 . Each of the profiler motor assembly  60  and the canter motor assembly  62 , in this example, includes two electric motors each rated at about 75 to 150 horsepower. The output of the two electric motors constituting profiler motor assembly  60  are, in this example, combined to drive first and second profiler cutter heads  50 ,  52  through a splined drive shaft  64 . The rotational movement of vertically oriented splined drive shaft  64  is transferred to the first and second profiler drive shafts  66 ,  68 , to which first and second profiler cutter heads  50 ,  52  are mounted, through first and second profiler gearboxes  70 ,  72 . Gearboxes  70 ,  72  slide along splined drive shaft  64  are supported on a support frame  42  by linear roller bearing assemblies. The vertical separation between gearboxes  70 ,  72 , and thus between first and second profiler cutting heads  50 ,  52  is changed by linear actuators  74 ,  76 , shown in  FIG. 5 . 
         [0028]    Canter  48  includes a canter gearbox  80  pivotally mounted to support frame  42  by a canter pivot housing  82 . Canter  48  includes first and second, overlapping canter cutter heads  84 ,  86  which are rotated about first and second canter axes  88 ,  90 . As with profiler motor assembly  60 , canter motor assembly  62  includes two electric motors each rated about 75 to 150 horsepower so that power from canter motor assembly  62  passes from the motor assembly, through canter gearbox  80  to the horizontal driveshafts which rotate first and second canter cutter heads  84 ,  86  about first and second canter axes  88 ,  90 . Canter pivot housing  82  is used to rotate gearbox  80  about a canter pivot axis  92  a small amount, such as plus or minus 2°, relative to support frame  42  and thus relative to first and second profiler cutter heads  50 ,  52 . The purpose for this is discussed below. 
         [0029]    The distance between the workpiece profiling station and the workpiece canting station is minimal. The horizontal distance between the centers of the workpiece profiling and canting stations, and thus between the centers of profiler  26  and canter  24  as defined by the profiler axes  54 ,  56  and canter axes  88 ,  90 , is preferably less than 24 inches; in this example the distance between the workpiece profiling and canting stations is 17.5 inches. This can be compared with the center-to-center distance between profiling and canting stations with conventional canter/profilers of about 60 to 96 inches. 
         [0030]    In the above example the profiler and canter cutter heads are milling cutter heads; in other examples other types of cutter heads such as disk type cutter heads, could be used. While there will usually be two profiler cutter heads, in appropriate circumstances the two canter cutter heads disclosed could be replaced by a single canter cutter head or more than two canter cutter heads. One or both of profiler axes  54 ,  56  could be oriented vertically instead of horizontally. If profiler axes  54 ,  56  are oriented vertically, they can be coaxial. Similarly, the axis for a canter cutter head could be oriented vertically instead of horizontally. 
         [0031]    Apparatus  40  also includes a stationary base frame  96 , base frame  96  including a lateral side plate  98  having a pair of linear rails  100 . Support frame  42  is mounted to and supported by a carriage  102 . Carriage  102  includes a lateral/horizontal slide assembly  104  mounted to lateral side plate  98  for movement along the linear rails  100 . Such lateral/horizontal movement of carriage  102  causes support frame  42  to move in a similar manner. Such movement of support frame  42  is generally perpendicular to the workpiece feed path  106  shown in  FIG. 3  with respect to partially processed cant  108 . In  FIG. 3  a roller  110  is shown supporting one end of the partially processed cant  108 . In practice three upper rollers and three lower rollers can be used on either side of apparatus  40  to support and drive the workpiece through apparatus  40  as is conventional. 
         [0032]    Carriage  102  also includes a vertical lift assembly  112  secured to lateral slide assembly  104  for vertical movement along the vertical rails  114  of assembly  112 . This movement raises and lowers support frame  42 , and cutter assembly  44  and motor assembly  58  therewith, in a vertical direction along a path laterally spaced apart from and perpendicular to the workpiece feed path  106 . 
         [0033]    Carriage  102  further includes a main pivot housing  116  mounted to vertical lift assembly  112 . Support frame  42  is mounted to and supported by main pivot housing  116  which not only provides vertical support for support frame  42  but also permits the support frame and the various components mounted thereto to rotate about a first axis  118 . The first axis  118  is farther away from the workpiece feed path  106  than is canter pivot axis  92 . First axis  118  is downstream of canter pivot axis  92  relative to the direction of movement  119  of partially processed cant  108 . 
         [0034]    The location of workpiece feed path  106  changes primarily depending on the size of the workpiece. Typically the lower support rollers  110  are fixed position so that as the size of the workpiece increases, the vertical position of the workpiece feed path  106  is raised. It is desired to keep the counter-rotating canter cutter heads  84 ,  86  centered on workpiece feed path  106  so that each canter cutter head cuts about the same amount of the workpiece to balance the load and to help ensure an appropriately smooth face  120  is created on the workpiece. Face  120  engages a guide anvil  121 , located between the profiler  46  and canter  48 , to help position the workpiece as it moves through apparatus  40 . 
         [0035]    The first and second profiler gearboxes  70 ,  72  are positioned vertically along splined drive shaft  64  to create appropriately sized and positioned side board profiles  122  in the workpiece. In addition, as illustrated in  FIGS. 6 and 7 , the relative transverse positions between canter cutter heads  84 ,  86  and profiler cutter heads  50 ,  52  can be changed by sliding canter  48  along upper and lower rails  126  connecting profiler  46  and canter  48 . Note that only the upper rail  126  is shown in  FIGS. 5 ,  6  and  7 . This movement is caused by hydraulic actuator  78 , see  FIG. 3 , and is parallel to axes  54 ,  56  so that profiler cutter heads  50 ,  52  and canter cutter heads  84 ,  86  are properly positioned for engaging the workpiece. 
         [0036]      FIG. 8  is a simplified top view of profiler  46  and canter  48  as shown in  FIGS. 6 and 7  but after support frame  42  and cutter assembly  44  therewith has been rotated 6° about first axis  118 . This rotation about first axis  118  is primarily used to follow the natural curvature of the workpiece so to maximize the amount of processed wood. However, because the canter profiler cutter heads are offset parallel to the workpiece feed path  106 , the best offset angle for the canter cutter heads  84 ,  86  will often not be the same for the profiler cutter heads  50 ,  52 . To accommodate this canter pivot housing  82  can rotate canter gearbox  80  about canter pivot axis  92  so that the angular orientation of first and second profiler cutter heads  50 ,  52  can be slightly different from the angular orientation of first and second canter cutter heads  84 ,  86 . In the example shown in  FIG. 9 , profiler cutter heads  50 ,  52  are offset by a 6° angle while canter cutter heads  84 ,  86  are offset by a 4° angle. In the present example the maximum offset angle possible by the movement of the main pivot housing  116  is plus or minus 6° while the maximum offset angle possible through the use of canter pivot housing  82  is plus or minus 2°. Other maximum offset angles are possible. In this example canter cutter heads  84 ,  86  are pivoted relative to profiler cutter heads  50 ,  52 ; in other examples profiler cutter heads  50 ,  52  could be pivoted relative to canter cutter heads  84 ,  86 . 
         [0037]      FIG. 10  illustrates another example of a canting and profiling apparatus with like reference numerals referring to like elements. In this example profiler motor assembly  60  and canter motor assembly  62  of motor assembly  58  are positioned above cutter assembly  44 . Motor assembly  60  and  62  are connected to profiler  26  and canter  24  by telescoping, constant velocity, Cardan joint or CV joint driveshafts  130  and canter and profiler gearboxes  132 ,  134 . A lateral positioning sliding base  136 , which corresponds to lateral slide assembly  104 , is used to adjust the lateral position of cutter assembly  44 . As with the example of  FIGS. 3-9 , cutter assembly  44  can be raised and lowered vertically to properly position the cutter assembly with the workpiece. 
         [0038]      FIGS. 11 and 12  are perspective views of a portion of a further example of a combination canting and profiling apparatus with like reference numerals referring to like elements. Motor assembly  58  includes first, second, third, fourth, fifth and sixth motors  151 - 156 . First and second profiler cutter heads  50 ,  52  are connected to driveshafts of the first and second motors  151 ,  152 . First and second canter cutter heads  84 ,  86  are connected to driveshafts of the third and fourth motors  153 ,  154 . 
         [0039]    In this example third-six motors  153 - 156  are drivingly and drivenly coupled to one another for load sharing. Motors  153 - 156  can be coupled to one another by gears mounted to the respective driveshafts. In this example profiler cutter heads  50 ,  52  are directly connected to the driveshafts of first and second motors  151 ,  152  while first and second canter cutter heads  84 ,  86  are directly connected to the driveshafts of third and fourth motors  153 ,  154  so that the cutters rotate the same speed as the driveshafts of their respective motors. In other examples the cutter heads need not be directly coupled to and rotated at the same speed as the driveshafts of the respective motors. In still other examples it may be desired to provide load sharing for motors  151 ,  152  driving first and second profiler cutter heads  50 ,  52 . 
         [0040]    The above descriptions may have used terms such as above, below, top, bottom, over, under, et cetera. These terms may be used in the description and claims to aid understanding of the invention and not used in a limiting sense. 
         [0041]    While the present invention is disclosed by reference to the preferred embodiments and examples detailed above, it is to be understood that these examples are intended in an illustrative rather than in a limiting sense. It is contemplated that modifications and combinations will occur to those skilled in the art, which modifications and combinations will be within the spirit of the invention and the scope of the following claims. 
         [0042]    One or more elements of one or more claims can be combined with elements of other claims. 
         [0043]    Any and all patents, patent applications and printed publications referred to above are incorporated by reference.