Abstract:
A machine for machining workpieces of wood and plastic has a transport path for transporting workpieces through the machine. One or more driven spindles having a tool for machining the workpieces transported through the machine are provided. An adjustable element that is adjustable relative to the tool is provided. At least one data storage is provided for storing data at least of the tool wherein the data are used to determine a position of the adjustable element relative to the tool and are retrievable. In the method for adjusting the machine, characteristic data of the tool are measured and stored in the data storage. The characteristic data are supplied to a control unit. In the control unit positioning data for the adjustable element are calculated based on the characteristic data and then made available for processing the workpieces.

Description:
BACKGROUND OF THE INVENTION  
         [0001]    1. Field of the Invention  
           [0002]    The invention relates to a machine for machining workpieces of wood, plastic, and the like, in particular, a molding machine, comprising a transport path for the workpieces, at least one driven spindle on which a tool is seated, and further at least one adjustable element. The invention also relates to a method for adjusting such a machine.  
           [0003]    2. Description of the Related Art  
           [0004]    In known woodworking machines, in particular, molding machines, the adjustment or retooling for the purpose of machining different workpieces is a time-consuming and complex process. Accordingly, pressing elements, which are correlated with the tools, or stops and tabletops must be adjusted in addition to the tools themselves. For this purpose, first the tool is placed onto the spindle. Subsequently, the pressing elements, the stops, or the tabletops can be adjusted relative to this tool. Because of this process, the adjustment of the machine is time-consuming. Moreover, it is not ensured that, based on the adjustment, the workpiece to be machined by the tool will fulfill the required machining precision. Accordingly, it is conventional to run at least one workpiece in a preliminary run through the machine to compare the resulting profile of the workpiece with a nominal profile, and, in the case of deviations, to readjust the corresponding elements of the machine. In particular, the precise adjustment of the pressing elements relative to the tool is complex and time-consuming. After the preliminary run of the workpiece, the pressing elements must often be readjusted in order to obtain the desired high machining precision of the workpiece. The pressing elements are to be moved as closely as possible toward the workpiece in order to guide the workpiece during machining as precisely and stably as possible.  
         SUMMARY OF THE INVENTION  
         [0005]    It is an object of the present invention to design the machine and the method of the aforementioned kind such that the adjustment and/or retooling on the machine can be performed within the shortest amount of time with high precision.  
           [0006]    In accordance with the present invention, this is achieved in regard to the machine in that the machine has at least one data storage in which data at least of the tool are stored, which data are used to determine the position to be adjusted of the adjustable element relative to the tool, and that the data can be retrieved for positioning the adjustable element.  
           [0007]    In accordance with the present invention, this is achieved in regard to the method in that the characteristic data of the tool are measured and stored in a data storage and that the data are supplied to a control unit which, under consideration of these data, calculates and makes available for further processing the position for the adjustable element.  
           [0008]    In the machine according to the invention, characteristic data of the tool are measured external to the machine and are stored in a data storage. Based on the tool data stored in the data storage the adjustable element, such as pressing elements, pressing guides or rules etc., can be precisely positioned without the tool being seated in the machine.  
           [0009]    When adjusting the machine, the characteristic data of the tool are supplied to a control unit which, based on the tool data, calculates and makes available for further processing the required position of the corresponding adjustable element.  
       
    
    
     BRIEF DESCRIPTION OF THE DRAWING  
       [0010]    In the drawing:  
         [0011]    [0011]FIG. 1 is a schematic illustration of a side view of a machine according to the invention;  
         [0012]    [0012]FIG. 2 is a plan view onto the machine according to FIG. 1, through which a wide workpiece is guided;  
         [0013]    [0013]FIG. 3 is a plan view of the machine according to the invention in an illustration corresponding to FIG. 2, through which a narrow workpiece is guided;  
         [0014]    [0014]FIG. 4 shows on an enlarged scale an upper spindle on which a tool with a large diameter is seated;  
         [0015]    [0015]FIG. 5 shows the upper spindle according to FIG. 4 on which a tool with a small diameter is seated;  
         [0016]    [0016]FIG. 6 shows on an enlarged scale a left spindle on which a tool with a large diameter is seated;  
         [0017]    [0017]FIG. 7 shows the left spindle according to FIG. 6, on which a tool with a small diameter is seated;  
         [0018]    [0018]FIG. 8 shows an axial control for the upper spindle of the machine according to the invention;  
         [0019]    [0019]FIG. 9 shows in a schematic illustration the circuit diagram of the axial control; and  
         [0020]    [0020]FIG. 10 shows a tool which is to be fastened on the spindles of the machine according to the invention.  
     
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0021]    The machine according to the invention is a molding machine with which workpieces are profiled when passing through the machine. The workpieces are used, for example, for manufacturing window frames or door frames. The machine has a machine bed  1  on which the workpieces  3  to be machine are transported by means of at least one feeding unit  4  on the upper side  2  of the machine bed  1 . The feeding unit  4  has a transport beam  5  which is positioned at a spacing above the machine bed  1  and which has feeding rollers  6  for transporting the workpieces  3  through the machine. The feeding rollers  6  are seated on horizontal shafts  7  which are supported on free ends of feeding pendulums  8 . The feeding pendulums  8  are supported on a pendulum holder  10  pivotable about a parallel axle  9  positioned between them. The pendulum holder  10  is fastened to the transport beam  5 . Pressure cylinders  11  engage the free ends of the feeding pendulums  8  and are supported on the transport beam  5 . They force the feeding rollers  6  onto the workpiece  3  to be transported. The transport beam  5  can be adjusted in the vertical direction.  
         [0022]    In the area below the feeding roller pair  6  shown in the right half of FIG. 1, a horizontal planing or dressing spindle  12  is provided. It has a planing table  13  arranged upstream thereof which can be adjusted in the vertical direction in order to adjust the cutting removal or cutting depth on the workpiece  3 . The planing or dressing spindle  12  is rotatably supported in the machine bed  1 . The two feeding rollers  6  are arranged in the area above the planing or dressing spindle  12  such that the shafts  7  of the feeding roller  6  are positioned on opposite sides of the axis of rotation of the planing spindle  12 , when viewed in a plan view. In FIG. 1, for reasons of simplifying the drawing, the tool, with which the underside of the workpiece  3  is machined and which is seated on the planing spindle, is illustrated only schematically in the form of its cutting circle.  
         [0023]    The feeding roller pair  6  shown to the right in FIG. 1 has arranged downstream thereof a vertical spindle  14  on which a tool, illustrated only schematically, is seated with which the right side of the workpiece  3  is machined when viewing the workpiece  3  in the transport direction.  
         [0024]    In the transport direction of the workpieces  3  behind the right vertical spindle  14  a vertical spindle  15  is arranged on which a tool, schematically illustrated, is seated with which the left side of the workpiece  3 , when viewed in the transport direction, is machined. At the level of this left spindle  15  a feeding roller pair  6 , illustrated at the center of FIG. 1, is positioned.  
         [0025]    In the feeding direction, at a spacing behind this central feeding roller pair  6 , the machine is provided with an upper horizontal spindle  16 . The tool seated thereon machines the upper side of the workpiece  3 .  
         [0026]    In the feeding direction of the workpiece  3 , at a minimal spacing behind the upper spindle  16 , a lower spindle  17  is provided in the machine bed  1  which has arranged with minimal spacing downstream thereof a table roller  18  supported in the machine bed. A tool, only schematically illustrated, is seated on the lower spindle  17  and machines the underside of the workpiece  3  when passing through the machine.  
         [0027]    The feeding roller  6  shown to the left in FIG. 1 is positioned with minimal spacing in the feeding direction of the workpieces  3  behind a suction hood  19  below which the spindle  16  is arranged. In the area of the suction hood  19  adjustable pressing elements  20  and  21  are provided which are arranged with minimal spacing before and behind the tool seated on the spindle  16  and rest against the upper side of the workpiece  3  when the workpiece  3  is fed through the machine. The corresponding adjusting device is known (German patent document 43 32 281 A1) so that it will be explained only briefly in the following. In FIG. 1, the corresponding adjusting devices  22  to  25  are illustrated schematically. By adjusting the pressing elements  20 ,  21  in these directions  22  to  25 , an optimal adaptation of the position of the pressing elements relative to the tool seated on the spindle  16  is realized, i.e., the pressing elements are advanced as closely as possible toward the tool. FIG. 10 shows in an exemplary fashion a tool  26  to be fastened on the spindle  16  and provided with profiled blades  27 . The blade profile  28  defines a maximum radius R max  as well as a minimal radius R min  of the tool  26 . The maximum radius R max  determines the maximum cutting circle radius, and the smallest radius R min  determines the minimum cutting circle radius of the tool  26 . The pressing elements  20 ,  21  (FIG. 1) are adjusted relative to the maximum radius R max  and the minimum radius R min  of the tool  26  seated on the spindle  16 . It is also possible to adjust the pressing elements  20 ,  21  relative to the maximum radius R max  and the fluting depth (groove depth) of the profile produced on the workpiece  3  by means of the profiled blade  27 . The fluting depth (groove depth) is defined by R max -R min  In this case, the pressing elements  20 ,  21  are adjusted by adjustment in the direction  23  and  24  relative to the maximum radius R max  and by adjustment in the direction  22  and  25  relative to the fluting depth (R max -R min ).  
         [0028]    The tool  26  which is illustrated as an example can be placed onto any suitable spindle of the machine.  
         [0029]    The transport beam  5  of the feeding unit  4  can be adjusted also in the vertical direction  29 , in order to adjust the feeding rollers  6  relative to the thickness of the workpiece  3  to be transported. However, it is also possible to adjust the transport beam  5  relative to the minimal cutting circle radius R min  of the tool  26  which is seated in this case on the upper spindle  16  and relative to the workpiece thickness together with the upper spindle  16 .  
         [0030]    The unmachined workpieces  3  are guided into the machine (FIG. 2) along a stop rule or stop guide  30  against which the workpieces  3  rest with their right side. The stop rule or guide  30  is adjustable transversely to the feeding direction of the workpiece  3  for adjusting the cutting depth or cutting removal of the tool seated on the right spindle  14 . The required cutting removal depends on the curvature and the oversize of the workpiece  3 . The term oversize in this connection is to be understood as the ratio of the workpiece blank width to the finished workpiece width. In the area downstream of the right spindle  14  a stop guide or rule  30 ′ is provided. In the feeding direction directly behind the right spindle  14  a stop  31  is positioned which is adjustable in the adjusting direction  32  relative to the tool seated on the right spindle  14 . The adjusting direction  32  is positioned parallel to the feeding direction of the workpiece  3 . The stop  31  is adjusted relative to the radii R max  and R min  of the tool seated on the spindle  14 .  
         [0031]    The right spindle  14  is located on a slide  35  which is adjustable in the direction of arrow  34  perpendicularly to the feeding direction of the workpiece  3 . By moving the slide  35  in the adjusting direction  34 , the right spindle  14  can be adjusted precisely relative to the workpiece  3  or the stop guide  30 ′ as a function of the tool seated on the spindle  14 .  
         [0032]    A tabletop  33  is positioned on the slide  35  and is also adjustable in the direction of arrow  34 . The tabletop  33  can also be adjusted relative to the slide  35  as well as the tool seated on the spindle  14  as a function of its maximum cutting circle radius R max .  
         [0033]    The right spindle  14  is positioned underneath a suction hood (not illustrated) with which the cuttings that are produced during machining of the workpiece  3  are removed. The left spindle  15  has also correlated therewith a suction hood  36 . Upstream and downstream of the left spindle  15  viewed in the feeding direction, pressing elements  37  and  38  are provided which rests against the left side of the workpiece  3  when viewed in the feeding direction and, like the pressing elements  20 ,  21  of the upper spindle  16  (FIG. 1), can be adjusted relative to the tool seated on the spindle  15 . The left spindle  15  is also supported on a slide  39  which is adjustable in the direction of arrow  40  perpendicularly to the feeding direction of the workpiece  3  in order to adjust the tool seated on the spindle  15  relative to the workpiece  3 . A tabletop  39 ′ is provided on the slide  39  which, like the tabletop  33 , is also adjusted relative to the maximum radius R max  of the respective tool.  
         [0034]    In the feeding direction at a spacing behind the left spindle  37 , two pressing rules or guides  41  and  42  are provided which are adjustable perpendicularly to the advancing direction of the workpiece  3  in the direction of arrows  43  and  44 . Accordingly, the pressing guides  41 ,  42  can be adjusted relative to the width of the workpiece  3 . The adjustment can also be realized relative to the minimal radius R min  of the tool seated on the left spindle  15 . The pressing guides  41 ,  42  can then be adjusted to the workpiece width together with the tool seated on the left spindle  15 .  
         [0035]    The feeding rollers  6  seated on the shafts  7  are adjusted such that they, in a plan view according to FIG. 2, rest in the direction of their width on the workpiece  3  whose width is, for example, larger than the width of the feeding rollers  6 . When advancing the workpiece  3  in the machine, first its underside is dressed with the tool seated on the planing or dressing spindle  12 . The planing table  13  (FIG. 1) is adjusted relative to the desired cutting removal (cutting depth) relative to the tool seated on the planing spindle  12 . Upon moving farther, the right side, in the feeding direction, is machined with the tool seated on the right spindle  14 . The tool seated on the left spindle  15  machines the left side of the workpiece  3  when moving farther through the machine. The upper side of the workpiece  3  is subsequently machined by the tool seated on the upper spindle  16 . By means of the tool seated on the lower spindle  17 , the underside of the workpiece  3  is finally machined again.  
         [0036]    [0036]FIG. 3 shows that also very narrow workpieces  3 , whose width is substantially smaller than the width of the feeding rollers  6 , can be processed in the machine. Because of the narrow width of the workpiece  3 , the left spindle  15  and the pressing rules  41 ,  42  must be adjusted perpendicularly to the feeding direction in the direction toward the stop rule or guide  30 . The slide  39  which supports the left spindle  15  is moved accordingly. In order to prevent a collision with the oppositely positioned feeding rollers  6 , the rollers  6  are axially returned according to the workpiece width and the radius R max  of the tool seated on the spindle  15 . In a plan view according to FIG. 3, the feeding rollers  6  are positioned only with a portion of their width above to the transport path of the workpiece  3 . The left spindle  15  with the suction hood  36  and the adjusting device for the pressing elements  37 ,  38  are arranged in the feeding direction of the workpiece  3  such that in the disclosed adjustment they will not collide with the feeding rollers  6  at the level of the planing spindle  12  and the neighboring stop rule  42 . The central feeding rollers  6  are adjusted in the direction of arrow  45  perpendicularly to the feeding direction together with the shafts  7  and/or the feeding pendulums  8  and the pendulum axle  9  and/or the pendulum holder  10 .  
         [0037]    As illustrated in FIGS. 2 and 3, the pressing elements  37 ,  38  of the left spindle can be adjusted in the same way as the pressing elements  20 ,  21  of the upper spindle  16 . In this way, a simple adjustment of the pressing elements  37 ,  38  relative to the tool seated on the left spindle  15  is possible.  
         [0038]    [0038]FIG. 4 shows on an enlarged scale the upper spindle  16  which is positioned in a suction chamber  46  of the suction hood  19 . The size of the suction chamber  46  is matched to the diameter of the tool seated on the spindle  16 . This is achieved in that the walls of the suction chamber  46  are formed at least partially of the carriers  47  to  49  of the pressing elements  20 ,  21 . The inner wall  50  of the suction chamber  46  extends approximately coaxially to the cutting circle diameter. The inner wall  50  has only a minimal spacing from the cutting circle diameter so that the cuttings, which are produced by machining the workpieces  3 , can reach optimally a suction channel  51  of the suction hood  19 .  
         [0039]    [0039]FIG. 5 shows the situation when the upper spindle  16  has a tool with a small cutting circle diameter seated thereon. According to this small cutting circle diameter, the pressing elements  20 ,  21  have been correspondingly adjusted. The carrier  49  for the pressing element  21  is moved downwardly in the direction of arrow  25 . The suction hood  19  has been moved in the direction of arrow  24  and the carrier  47  in the direction of arrows  22  and  23 . In this way, the size of the suction chamber  46  has been automatically decreased with the adjustment of the pressing elements  20 ,  21  and thus matched to the smaller tool on the spindle  16 . The boundary of the suction chamber  46 , which is formed by the inner walls of the carriers  47  to  49 , is thus adjusted correspondingly when an adjustment of the pressing elements  20 ,  21  is carried so that an automatic volume adaptation of the suction chamber  46  is achieved. In this way, it is possible that the cuttings, produced by a tool having a smaller cutting circle diameter, can be optimally removed by suction into the suction channel  51 . FIG. 5 shows as an example the situation when the tool seated on the spindle  16  has no fluting depth, i.e., the blades of this tool have a constant outer cutting diameter across their length. FIG. 4, on the other hand, shows the situation when the tool seated on the spindle  16  is a profiled blade with a fluting depth.  
         [0040]    [0040]FIG. 6 shows in a plan view the left spindle  15  on which a tool with a large cutting circle diameter is seated. The tool seated on the left spindle  15  has in the described embodiment no profiled blade but a blade with straight cutting edge so that this blade does not have a profile depth. The tool or the spindle  15  is positioned in a suction chamber  52  of the suction width  36 . The two pressing elements  37 ,  38  upstream and downstream of the spindle  15  are adjusted in the same way as the pressing elements  20 ,  21  of the upper spindle  16 . In accordance with the suction hood  19 , the suction chamber  52  is delimited by the carriers  53  to  55  of the pressing elements  37 ,  38 . At the level of the suction channel  56  an adjusting element  57  is provided that is pivotable about an axis  58  extending parallel to the spindle axis. The adjusting element  57  has a curved slot  59  engaged by a guide element  60  which is provided on the suction hood  36 . The adjusting element  57  has an end face  61  facing the spindle  15  and forming a part of the inner wall  62  of the suction chamber  52 . As in the case of the suction hood  19 , the suction chamber  52  is delimited also by the end faces  63  and  64  of the pressing elements  37 ,  38  facing the spindle  15 . The suction channel  56  as well as the suction channel  51  adjoin tangentially the suction chamber  52 . An inlet opening  65  extends between the end face  61  of the adjusting element  57  and the oppositely positioned inner wall portion  66 . Accordingly, the inner wall  62  of the suction chamber  52  is matched approximately to the cutting circle diameter of the tools seated on the spindle  15 . The inner wall  62  has only a minimal spacing from the cutting circle diameter. Accordingly, the cuttings which are produced during machining of the workpiece  3  are guided via the inlet opening  65  reliably into the suction channel  56 . The end face  61  of the adjusting element  57  is formed by a cuttings guide plate which ensures that the cuttings are guided reliably to the inlet opening  65 .  
         [0041]    [0041]FIG. 7 shows the situation in which on the spindle  15  a tool with a small outer cutting circle diameter is positioned. This tool has also blades with straight cutting edges. The pressing elements  37 ,  38  are matched to the new outer cutting circle diameter by corresponding adjustments. Moreover, the adjusting element  58  is pivoted counter-clockwise about the axis  58 . The end face  61  is then no longer approximately tangentially positioned relative to the outer cutting circle diameter, as was the case in the position according to FIG. 6, but approximately radially. Otherwise, the carriers  53  to  55  have been moved for adjusting the pressing elements  37 ,  38  in the same way as has been explained in connection with the pressing elements  20 ,  21 .  
         [0042]    As a result of the adjustment of the adjusting element  57  it is ensured that the inlet opening  65  is positioned close to the circumference of the tool. By doing so, the cuttings which are produced by machining the workpiece  3  are reliably sucked into the suction channel  56 . The pressing elements  37 ,  38  are positioned with their end faces  63 ,  64  so as to be adjacent to the outer cutting diameter of the tool.  
         [0043]    [0043]FIG. 8 shows the axial control with the aid of the example of the upper spindle  16  of the machine. The tool  26  with which the upper side of the workpiece can be machined is seated on the spindle  16 . The workpiece  26  or the spindle  16  is positioned at a spacing above a machine table  67  of the machine. It is provided on a machine frame  68  which is part of the machine bed  1 . For adjustment to different workpieces of different thickness, respectively, to different outer cutting circle diameters of the tool, the spindle  16  must be adjusted in the radial direction  69  relative to the machine table  67 . For this purpose, in the machine bed a positioning motor  70  is provided which drives by means of the gear box  71 , preferably a bevel gear pair, a vertically arranged spindle  72 . The spindle  72  is preferably a trapezoidally threaded spindle. On the spindle  72 , a spindle slide  73  carrying the spindle  16  is supported by means of a nut  74 , preferably having a trapezoidal thread. By rotating the spindle  72 , the spindle slide  73  is adjusted by means of the nut  74  in the vertical direction  69  in order to adjust the spindle  16  in the desired position.  
         [0044]    In order to be able to reliably adjust and/or read the displacement travel of the spindle slide  73  and thus of the spindle  16 , a travel measuring system  75  is provided. It has a read head  76  fastened on the machine frame  68  and has correlated therewith a graduation  77  provided on the spindle slide  73 . The read head  76  is connected by electrical lines  78  to a computer, a monitor or the like. In order to define final positions for the spindle slide  73  limit switches (not illustrated) can be provided.  
         [0045]    A control system  79  is positioned upstream of the positioning motor  70  (FIG. 9). The control system  79  receives from a control unit  80  nominal values  81  which can be compared in the control system  79  with actual values  83  provided by the measuring system  75 . Moreover, the control system  79  receives from the positioning motor  70  signals  82  which characterize the rotational speed of the positioning motor  70 . As soon as the spindle slide  73  and thus the spindle  16  have reached a certain position, which is determined by the measuring system  75 , the rotational speed of the motor  70  is reduced. This is illustrated in the rotational speed/travel diagram of FIG. 9. It is shown here that the motor  70  first adjusts at a high rotational speed the spindle slide  73  up to a certain position. As soon as this position has been reached, the rotational speed of the motor  70  is lowered, wherein the spindle slide  73  and spindle  16  can be moved position-controlled via the measuring system  75  into the desired position. In the control system  79  the comparison of the nominal values  81  provided by the control unit  80  and of the actual values  82  and  83  provided by the motor  70  and the measuring system  75  is carried out. As a result of the described position-controlled movement of the spindle  16 , a high positioning precision is achieved. As soon as the spindle  16  has reached its desired position, the position control is switched off.  
         [0046]    In conventional machines the adjustment or retooling with regard to other workpieces is time-consuming and complicated. In particular, at least one workpiece must be transported through the machine in a preliminary run in order to compare the produced profile with the nominal profile and to perform readjustments should deviations occur. In the described machine the tool data are measured external to the machine and are stored in a data storage of the control unit in the form of data values. The tool data are the radial dimensions as well the axial dimension of the tool. FIG. 10 shows the tool  26  whose profiled blades  27  have the blade profile  28 . As a result of this profile  28 , the tool  26  has a minimum radius R min  as well as a maximum radius R max . The fluting depth (groove depth) of the profiled blade  27  is defined by R max -R min . Moreover, the axial dimension A of the tool  26  is measured. This tool dimension A is the spacing of a characteristic location of the blade profile  28  from a contact surface  84  of the tool  26  on the spindle  16 . The above-mentioned tool data are measured external to the machine directly on the tool and stored. Moreover, the data storage stores the workpiece data, such as thickness, width, and respective profiled dimensions. Based on these tool and workpiece data stored in the storage device it is possible to adjust the adjustable spindles of the machine in the axial and radial direction, the corresponding pressing elements  20 ,  21 ;  37 ,  38 , the pressing guides  41 ,  42 , the tabletops  33 ,  39 ′, the transport beam  5 , the feeding rollers  6 , the dressing or planing table  13 , and the stop rule  30 , without the tool having to be seated in the machine. When subsequently the tool required for machining is placed onto the corresponding spindle with the selected adjustment of the machine, it is possible to immediately perform the desired processing of the workpieces  3 . A preliminary or sample run is not required. The retooling time from one workpiece profile to another is accordingly very short; skilled personnel for machine retooling are not required.  
         [0047]    Advantageously, the position adjustment is carried out fully automatically. However, for a simpler embodiment of the machine it is also possible to show the operator on a display of the control unit which adjustment of the machine must be performed. The operator can then manually adjust the corresponding adjustable parts of the machine according to the displayed nominal position values. Also, it is advantageously possible to perform the greatest part of the adjustments fully automatically and to perform an adjustment by hand only for a few elements which must be adjusted seldomly. Such an element is, for example, the stop  31 .  
         [0048]    In the case of the upper spindle  16  and the left spindle  15  the fluting depth of the tool (R max -R min ) and the radial dimension (R max ) of the tool are required for adjusting the pressing elements  20 ,  21  and  37 ,  38 .  
         [0049]    In order to adjust the left pressing rules  41 ,  42  in the adjusting direction  43 ,  44  (FIG. 2), the smallest outer cutting circle radius R min  of the left tool is used as a basis for the adjustment. The pressing guides  41 ,  42  are adjusted such that their contact surfaces  85 ,  86  are positioned tangentially to the smallest cutting circle diameter R min  of the tool.  
         [0050]    When adjusting the machine to the workpiece  3  to be processed, first the pressing elements  20 ,  21 ;  37 ,  38  as well as the pressing guides  41 ,  42  are adjusted to the required position in the manner described. Subsequently, the respective tool, together with the adjustable elements adjusted as described, is adjusted relative to the workpiece to be machined in the axial and radial direction. Alternatively, the feed rollers  6  and the pressing guides  41 ,  42  can be directly adjusted relative to the workpiece  3  into their desired or required position. For these adjustments, an adjusting drive is used, respectively, as is illustrated with the aid of FIG. 8 for the upper spindle  16 .  
         [0051]    All adjustments are carried out via a control unit and via the operating panel of the machine.  
         [0052]    For adjusting the spindles it is possible to provide, for example, CNC axles whose control is however complex and expensive. It is also known to drive a spindle by means of a motor on whose shaft a shaft encoder for position measuring is positioned. The rotational movement of the spindle is transformed by means of a trapezoidal thread into a linear movement of the spindle. Such axles are constructively simple and inexpensive but do not allow a high positional precision because of the play as well as wear and manufacturing tolerances of these axles. Should a high positional precision not be required, for example, in the adjustment of planing or dressing tables  13  or of the stop  30  or transport beam  5 , such simple axles can be used in the described machine. For a high positional precision in the machine described here, the spindle  72  (FIG. 8) is directly driven or driven by means of a gearbox  71  by the motor  70 . The adjusting stroke of the spindle slide  73  is measured directly on the spindle slide  73  by means of the measuring system  75 . The adjusting travel is supplied as an actual signal  83  to the control system  79  (FIG. 9). The control system  79  compares the actual value with the nominal value  81  provided by the control unit  80  and controls accordingly the motor  70  so that the spindle slide  73  and thus the spindle can be moved exactly into the nominal position. In this connection, it is unimportant whether the transmission chain from the motor  70  to the spindle slide  73  has elements with play because the measuring system  75  directly measures the adjusting stroke of the spindle slide  73 . For measuring the adjusting stroke a linear graduation (rule) can be used which has the required high measuring precision for the required application, respectively. The measuring system  75  can be in the form of any suitable linear measuring system.  
         [0053]    With the aid of FIGS. 8 and 9, the adjustment of the upper spindle  16  has been explained. The other elements of the machine to be adjusted with high precision are adjusted also in the same way, in particular, the spindles and the pressing elements.  
         [0054]    A further important feature of the machine is that the feeding rollers  6  have a width which is matched to the maximum possible width dimension of the workpieces  3  to be machined in the machine. Depending on the width of the workpiece  3  guided through the machine, the shafts  7  supporting the feeding rollers  6  are adjusted axially such that the feeding rollers  6  rest with optimal width on the workpiece  3 . FIG. 2 shows the situation in which a very wide workpiece  3  is transported through the machine. The shafts  7  of the feeding rollers  6  are adjusted such that the feeding rollers  6  rest with their entire width on the workpiece  3 .  
         [0055]    When narrow workpieces  3  are to be transported through the machine (FIG. 3), the feeding rollers  6  or their shafts  7  can be returned in the axial direction  45  so that the feeding rollers  6  rest only over a portion of their width on the workpiece  3 . In FIG. 3 this is illustrated for the feeding rollers  6  positioned opposite the left spindle  15 . Since the feeding rollers  6  must not be positioned highly precisely, a conventionally controlled axle suffices for their adjustment. The feeding rollers  6  are adjusted axially to such an extent that they will not collide with the neighboring tool on the left spindle  15 . The adjusting value depends in this connection on the greatest cutting circle radius R max  of the tool  26 . Since for narrow workpieces the left spindle  15  is adjusted transversely to the feeding direction of the workpieces  3 , a corresponding axial movement of the oppositely positioned feeding rollers  6  is required. The feeding rollers  6  correlated with the planing spindle (dressing spindle)  12  must not be axially adjusted but can remain in their position.  
         [0056]    As a result of the axial movement of at least some of the feeding rollers  6 , an exchange of feeding rollers is not required as would be the case in conventional machines: depending on the width of the workpieces to be machined, different feeding rollers of different widths are positioned on the shafts in conventional machines. Since machines as described have a large number of feeding rollers, the retooling requires a considerable amount of time. It is also known to adjust the feeding rollers axially by hand. However, the manual adjustment is time-consuming and entails the risk that upon positioning of the left spindle a collision with erroneously adjusted feeding rollers can occur. In the described machine, the corresponding feeding rollers can be quickly axially adjusted so that retooling of the machine is possible within a shortest amount of time with high precision. The corresponding feeding rollers  6  or their shafts  7  are adjusted by the control unit  80  when corresponding workpieces are to be machined. This ensures that no collision will occur between the feeding rollers  6  and the tool.  
         [0057]    When axially adjusting the feeding rollers  6 , the largest cutting circle radius R max  of the tool and the width of the workpiece  3  to be machined are to be taken into account.  
         [0058]    While specific embodiments of the invention have been shown and described in detail to illustrate the inventive principles, it will be understood that the invention may be embodied otherwise without departing from such principles.