Abstract:
A feeding apparatus of a moved body includes: a base; a rotatable long ball screw extending in a longitudinal direction of the base; a nut member engaged with the long ball screw; a moved body mounted to the nut member; a pair of drive shafts arranged in parallel to the long ball screw and being provided with a ball screw; driving and transmitting members connecting both outer end portions of each of the drive shafts to both ends of the long ball screw; drive motors connected to both inner end portions of each of the drive shafts; and an intermediate support supporting the long ball screw and each of the drive shafts. The intermediate support is provided with a nut member which is engaged with the ball screw. Therefore, the intermediate support is moved in a longitudinal direction by rotation of the long ball screw.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a feeding apparatus of a moved body which moves a moved body such as a carriage provided with a work clamp for clamping a workpiece in a sheet material working machine, for example, a turret punch press or the like. 
     2. Description of the Related Art 
     In a conventional turret punch press corresponding to a sheet material working machine, the turret punch press includes a feeding apparatus  101  corresponding to a moved body for moving a workpiece wherein a carriage base  103  extending in a lateral direction as shown in FIG. 1 is provided in such a manner as to move in a direction of a Y-axis (a vertical direction in FIG.  1 ). A nut member is provided in a lower portion in a substantially center portion of the carriage base  103 , and a rotatable ball screw  105  extending in the direction of the Y-axis is provided in the nut member. One end of the ball screw  105 , for example, a lower end in FIG. 1 is supported to a bearing  107 , and another end of the ball screw  105 , for example, an upper end in FIG. 1 is connected to an output shaft of a Y-axis servo motor  111  mounted to a motor base  109 . 
     In the structure mentioned above, when driving the Y-axis servo motor  111 , the ball screw  105  is rotated and the carriage base  103  is moved in the direction of the Y-axis via the nut member. 
     Further, a rotatable long ball screw  113  is extended along a direction of an X-axis of the carriage base  103 , one end of the long ball screw  113 , for example, a left end in FIG. 1 is supported to a bearing  115 , and another end of the long ball screw  113 , for example, a right end in FIG. 1 is connected to an output shaft of an X-axis servo motor  119  mounted to a motor base  117 . In this case, the motor base  117  is mounted on the carriage base  103 . A nut member  121  ( 121 ′ in FIGS. 3 and 4) is engaged with the long ball screw  113 , and a carriage  123  ( 123 ′ in FIG. 3) is integrally provided in the nut member  121 . A plurality of work clamps  125  for clamping a workpiece W are provided in the carriage  123 . 
     In the structure mentioned above, when driving the X-axis servo motor  119 , the long ball screw  113  is rotated and the carriage  123  is moved in the direction of the X-axis via the nut member  121 , so that the workpiece W clamped by the work clamp  125  is moved in the direction of the X-axis. Accordingly, the workpiece W is moved in the direction of the X-axis and the direction of the Y-axis. 
     Further, a structure shown in FIG. 2 has been known as another feeding apparatus  127  which moves the workpiece. In FIG. 2, the same reference numerals are attached to the same elements as the elements in FIG.  1  and an overlapping description will be omitted. In FIG. 2, one end and another end of the long ball screw  113 , for example, a left end and a right end in FIG. 2 are connected to output shafts of X-axis servo motors  133  and  135  mounted to motor bases  129  and  131 . In this case, the motor bases  129  and  131  are mounted on the carriage base  103 . 
     In the structure mentioned above, when driving the X-axis servo motors  133  and  135 , the long ball screw  113  is rotated and the carriage  123  is moved in the direction of the X-axis via the nut member  121 , so that the workpiece W clamped by the work clamp  125  is moved in the direction of the X-axis. Accordingly, the workpiece W is moved in the direction of the X-axis and the direction of the Y-axis. 
     Further, there is another turret punch press as shown in FIGS. 3 to  5 . The turret punch press is partly described in a German Patent Application, Laid-Open No. DE 198 21 763 A1, Laid-Open on Nov. 19, 1998. 
     In FIGS. 3 and 4, the same reference numerals are attached to the same elements as the elements in FIG.  2  and an overlapping description will be omitted. In FIGS. 3 and 4, a long ball screw spline  139  is used in place of the long ball screw  113 , and the output shafts of the X-axis servo motors  133  and  135  are connected to both ends of the long ball screw spline  139 . Linear guides  141  and  143  are extended to right and left portions on the carriage base  103 . A plurality of intermediate supports  145  are provided so as to move in a lateral direction by being guided along the linear guides  141  and  143 . Further, each of the intermediate supports  145  supports the long ball screw spline  139  when the long ball screw spline  139  rotates and the nut member  121 ′ moves in the lateral direction. 
     The intermediate support  145  is in detail shown in FIG.  5 . In FIG. 5, the long ball screw spline  139  is constituted by a ball screw portion  139 B and a spline portion  139 S. Further, the intermediate support  145  is structured such that a first intermediate support main body  147  guided along the linear guide  141  or  143  and a second intermediate support main body  149  supporting the long ball screw spline  139  are integrally formed. A spline outer cylinder portion  151  and a ball screw nut portion  153  are provided within the second intermediate support main body  149  via support bearings  155  and  157 . A width D of the intermediate support is between 250 mm and 300 mm. 
     The spline outer cylinder portion  151  is engaged with the spline portion  139 S of the long ball screw spline  139  and the ball screw nut portion  153  is engaged with the ball screw portion  139 B of the long ball screw spline  139 . Further, for example, a pulley  159  is connected to the spline outer cylinder portion  151  by a bolt and for example, a pulley  161  is connected to the ball screw nut portion  153  by a bolt. 
     On the contrary, a rotatable shaft  163  is supported in a lateral direction corresponding to a longitudinal direction of the first intermediate support main body  147  and the other pulleys  165  and  167  are respectively attached to both ends of the shaft  163 . Timing belts  169  and  171  are respectively wound between the pulleys  159  and  165  and between the pulleys  161  and  167 . 
     In accordance with the structure mentioned above, when the long ball screw spline  139  is rotated as shown by an arrow in FIG. 5, the pulley  159  is rotated in the same direction as a rotational direction of the long ball screw spline  139  via the spline portion  139 S. The rotation of the pulley  159  is transmitted to the shaft  163  via the timing belt  169  and the pulley  165  and the shaft  163  is rotated. Further, the rotation of the shaft  163  is transmitted to the pulley  161  via the pulley  167  and the timing belt  171  and the pulley  161  is rotated, so that the ball screw nut portion  153  is moved, for example, in a rightward direction in FIG.  5 . 
     In FIG. 5 mentioned above, when setting a ratio between diameters of the pulleys  159  and  165  to 1:1 and setting a ratio between diameters of the pulleys  161  and  167  to 1:½, a moving amount of each of the intermediate supports  145  becomes a half of a moving amount of the carriage  123 , whereby a moving operation is performed. In the drawing, reference symbol E denotes a mounting distance between the respective intermediate supports  145 . 
     In this case, as shown in FIGS. 3 and 4, the structure is made such that the intermediate supports  145  are provided for a high speed and a stabilization of the system, however, as shown in FIG. 5, there is employed a method of assembling the intermediate support  145  on the long ball screw spline  139  as shown in FIG.  5 . In this case, since it is necessary to provide the spline outer cylinder portion  151 , the ball screw nut portion  153 , the pulleys  159 ,  161 ,  165  and  167  and the timing belts  169  and  171  in the intermediate support  145  itself, there is a disadvantage that a width D of the intermediate support  145  is increased in view of the construction. 
     Since the width D, for example, between 250 mm and 300 mm does not affect on the long ball screw spline  139  in view of a space and becomes a wasteful dimension, it is necessary to lengthen the long ball screw spline  139  at the degree so as to secure an effective length, so that the distance E between the supports of the long ball screw spline  139  by the intermediate supports  145  becomes necessarily increased and it is impossible to increase a danger speed. Accordingly, there is a problem that it is impossible to make the speed of the shaft high. 
     Further, since it is necessary to increase the length of the carriage base  103  supporting the long ball screw spline  139  when the long ball screw spline  139  becomes long, a weight thereof is increased. Accordingly, in the case that a vibration is generated at a time of punching, for example, in a punch press, there is a problem that the vibration can not be reduced. 
     SUMMARY OF THE INVENTION 
     The present invention is made for solving the problems mentioned above, and an object of the present invention is to provide a feeding apparatus of a moved body in which a high speed structure can be obtained by making a width of an intermediate support not longer than a conventional one and making a length of a long ball screw not longer than a conventional one and a vibration generated at a time of punching, for example, in a punch press is reduced. 
     In order to achieve the object mentioned above, in accordance with a first aspect of the present invention, there is provided a feeding apparatus of a moved body, comprising: a base; bearings provided on the base at both ends of the base; a rotatable long ball screw extending in a longitudinal direction of the base, the long ball screw being supported by the bearings; a nut member engaged with the long ball screw; a moved body mounted to the nut member; a pair of drive shafts arranged in parallel to the long ball screw, the drive shafts provided with a ball screw; driving and transmitting members connecting both outer end portions of each of the drive shafts to both ends of the long ball screw; drive motors mounted on the base, each of the drive motor being connected to both inner end portions of each of the drive shafts; and an intermediate support supporting the long ball screw and each of the drive shafts, the intermediate support being provided with a nut member which is engaged with the ball screw provided on the drive shaft, the intermediate support being moved in a longitudinal direction of the long ball screw and each of the drive shafts by rotation of the drive shafts. 
     Accordingly, when driving each of the drive motors, each of the drive shafts is rotated and the long ball screw is rotated via each of the driving and transmitting member. The long ball screw is rotated, whereby the moved body is moved in the longitudinal direction of the long ball screw via the nut member. When the moved body is moved, the intermediate support supporting each of the drive shafts and the long ball screw also supports each of the drive shafts and the long ball screw while moving in the same direction as a moving direction of the moved body. 
     As a result, a high speed structure can be obtained by making a length of the long ball screw not longer than a conventional one and a vibration generated at a time of punching, for example, a punch press. 
     In accordance with a second aspect of the present invention, as it depends from the first aspect, there is provided a feeding apparatus of a moved body, in which the moved body is a carriage provided with a work clamp for clamping a workpiece. 
     Accordingly, since the moved body is the carriage provided with the work clamp for clamping the workpiece, the workpiece clamped by the work clamp is smoothly moved at a high speed. 
     In accordance with a third aspect of the present invention, as it depends from the first or the second aspect, there is provided a feeding apparatus of a moved body, in which a plain bearing slid by the long ball screw are provided in the intermediate support. 
     Accordingly, the ball screw corresponding to each of the drive shafts is rotated, whereby the nut member is rotated and the plain bearing is slid in the longitudinal direction of the long ball screw. Therefore, the intermediate support is smoothly moved in the longitudinal direction of the long ball screw at a high speed while always supporting the long ball screw. 
     As a result, it is possible to make the width of the intermediate support not longer than the conventional one and a supporting width of the long ball screw can be minimized. 
     In accordance with a fourth aspect of the present invention, as it depends from one aspect among the first aspect to the third aspect, there is provided a feeding apparatus of a moved body, in which the long ball screw is provided with a spline on an outer periphery in the longitudinal direction of the long ball screw; and the intermediate support is provided with a spline outer cylinder engaged with the spline provided in the long ball screw. 
     Accordingly, the ball screw corresponding to each of the drive shafts is rotated, whereby the nut member is rotated and the spline outer cylinder is slid in the longitudinal direction by the spline of the long ball screw. Therefore, the intermediate support is smoothly moved in the longitudinal direction of the long ball screw at a high speed while always supporting the long ball screw. 
     As a result, it is possible to make the width of the intermediate support not longer than the conventional one and a supporting width of the long ball screw can be minimized. 
     In accordance with a fifth aspect of the present invention, as it depends from one aspect among the first aspect to the fourth aspect, there is provided a feeding apparatus of a moved body, in which a ratio between a lead of the long ball screw and a lead of each of the ball screws is selected to achieve a predetermined rate of movement of the intermediate support. 
     Accordingly, by selecting the ratio between the lead of the long ball screw and the lead of each of the ball screws to the proper rate, as well as the long ball screw is rotated and the moved body is moved in the longitudinal direction of the long ball screw, the moving speed of the intermediate support is increased and reduced in accordance with a more proper rate than the moving speed of the moved body. 
     In accordance with a sixth aspect of the present invention, as it depends from one aspect among the first aspect to the fifth aspect, there is provided a feeding apparatus of a moved body, in which a transmission ratio of each of the driving and transmitting members is set to 1:1; and a ratio between the lead of the long ball screw and the lead of each of the ball screws is set to 1:½. 
     Accordingly, by setting the transmission ratio of each of the driving and transmitting members to 1:1 and setting the ratio between the lead of the long ball screw and the lead of each of the ball screws to 1:½, the long ball screw is rotated and the moved body is moved in the longitudinal direction of the long ball screw, and the moving speed of the intermediate support is reduced at a half of the moving speed of the moved body. 
    
    
     BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS 
     The above and further objects and novel features of the present invention will more fully appear from the following detailed description when the same is read in conjunction with the accompanying drawings, in which: 
     FIG. 1 is a plan view of a conventional feeding apparatus; 
     FIG. 2 is a plan view of another conventional feeding apparatus; 
     FIG. 3 is a plan view of the other conventional feeding apparatus; 
     FIG. 4 is a front elevational view in FIG. 3; 
     FIG. 5 is an enlarged front elevational cross sectional view of a conventional intermediate support; 
     FIG. 6 is a plan view of a feeding apparatus in accordance with the present invention; 
     FIG. 7 is a front elevational view in FIG. 6; 
     FIG. 8 is a side elevational view in FIG. 6; 
     FIG. 9 is an enlarged front elevational cross sectional view of an intermediate support; and 
     FIG. 10 is an enlarged front elevational cross sectional view of an intermediate support in place of FIG.  9 . 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     A description will be given below of an embodiment of a feeding apparatus of a moved body in accordance with the present invention with reference to the accompanying drawings. 
     With reference to FIGS. 6,  7  and  8 , for example, in a turret punch press corresponding to a sheet material working machine, a feeding apparatus  1  corresponding to a moved body for moving a workpiece W is structured such that a carriage base  3  corresponding to an embodiment of a base extending in a lateral direction in FIGS. 6 and 7 is provided in such a manner as to move in a direction of a Y-axis (a vertical direction in FIG.  6 ). A nut member  5  is provided in an upper portion in a substantially center portion of the carriage base  3 , and a rotatable ball screw  7  extending in the direction of the Y-axis is provided in the nut member  5 . One lower end of the ball screw  7  is supported to a bearing (not shown), and another upper end of the ball screw  7  is connected to an output shaft of a Y-axis servo motor mounted to a motor base (not shown). 
     In the structure mentioned above, when driving the Y-axis servo motor (not shown), the ball screw  7  is rotated and the carriage base  3  is moved in the direction of the Y-axis via the nut member  5 . 
     Further, a rotatable long ball screw  9  is extended along a direction of an X-axis of the carriage base  3 , and both ends of the long ball screw  9 , for example, right and left ends in FIG. 6, are rotatably supported by bearings  11  and  13 . A nut member  15  is engaged with the long ball screw  9 , and a carriage  17  is integrally provided in the nut member  15 . A plurality of work clamps  19  for clamping a workpiece W corresponding to an example of the moved body are provided in the carriage  17 . 
     Ball screws  21  and  23  respectively extending in left and right directions from a substantially center portion in the longitudinal direction of the long ball screw  9  are provided in parallel to the long ball screw  9 . X-axis servo motors  29  and  31  corresponding to an embodiment of a drive motor are connected to inner ends of the ball screws  21  and  23 , that is, in a substantially center portion side in a longitudinal direction of the long ball screw  9  by couplings  25  and  27 , respectively. The X-axis servo motors  29  and  31  are mounted to motor bases  33  and  35  provided on the carriage base  3 . Both ends of the ball screws  21  and  23  are rotatably supported by bearings  37  and  39 ;  41  and  43 , respectively. 
     Pulleys  45  and  47  corresponding to an embodiment of a driving and transmitting member are attached to both ends of the long ball screw  9 , and pulleys  49  and  51  corresponding to an embodiment of a driving and transmitting member are attached to a left end and a right end of the ball screws  21  and  23 . Timing belts  53  and  55  are respectively wound between the pulleys  45  and  49  and between the pulleys  47  and  51 . 
     In accordance with the structure mentioned above, when driving the X-axis servo motors  29  and  31 , the ball screws  21  and  23  are rotated. When the ball screws  21  and  23  are rotated, the long ball screw  9  is rotated via the pulley  49 , the timing belt  53  and the pulley  45 ; and the pulley  51 , the timing belt  55  and the pulley  47 . Sine the long ball screw  9  is rotated, whereby the carriage  17  is moved in the direction of the X-axis via the nut member  15 , the workpiece W clamped by the work clamp  19  is moved in the direction of the X-axis. Accordingly, the workpiece W is moved in the direction of the X-axis and the direction of the Y-axis. 
     An intermediate support  57  is attached to each of the long ball screw  9  and the ball screws  21  and  23 . Each of the intermediate supports  57  are provided on the carriage base  3  as shown in FIG.  7  and is structured such as to be moved in a lateral direction by being guided by each of linear guides  59  extending in a lateral direction. A detailed structure of the intermediate support  57  is, for example, well illustrated in FIG.  9 . In FIG. 9, the intermediate support  57  is guided by the linear guide  59  and is provided with an intermediate support main body  61  for supporting the long ball screw  9  and the ball screws  21  and  23 . A nut member  63  engaged with the ball screws  21  and  23  and a plain bearing  65  slid in a lateral direction with respect to the long ball screw  9  are provided in the intermediate support main body  61 . 
     In accordance with the structure mentioned above, when the ball screws  21  and  23  are rotated as shown by an arrow in FIG. 9, the intermediate support main body  61  is moved, for example, in a rightward direction in FIG. 9 via the nut member  63 , and it is possible to smoothly move the intermediate support main body  61  in the rightward direction in FIG. 9 at a high speed via the plain bearing  65  with respect to the long ball screw  9 . Further, when the ball screws  21  and  23  are rotated, the long ball screw  9  is rotated via the pulley  49 , the timing belt  53  and the pulley  45 ; and the pulley  51 , the timing belt  55  and the pulley  47 . Since the carriage  17  is moved in the direction of the X-axis via the nut member  15  when the long ball screw  9  is rotated, the workpiece W clamped by the work clamp  19  is moved in the direction of the X-axis. 
     In FIG. 9, when setting a ratio of a diameter between the pulleys  45  and  49  and a ratio of a diameter between the pulleys  47  and  51  to 1:1 and properly selecting a lead ratio between a lead of the ball screws  21  and  23  and a lead of the long ball screw  9 , it is possible to self-propel the intermediate support main body  61  on the long ball screw  9  at a necessary speed. For example, when setting the lead of the ball screws  21  and  23  to a half of the lead of the long ball screw  9 , it is possible to move the intermediate support main body  61  with respect to the long ball screw  9  at a half speed. Accordingly, it is possible to move each of the intermediate supports  57  at a moving speed corresponding to a half of a moving speed of the carriage  17 . 
     Further, each of the intermediate supports  57  on the long ball screw  9  has only a width D 2  of the plain bearing  65 , for example, 50 mm or less, so that a conventional nut member, pulley and the like are not required. Accordingly, it is possible to reduce a width at 200 to 250 mm in one side in comparison with the conventional width, for example, 250 to 300 mm and it is possible to minimize the supporting width by each of the intermediate supports  57 . 
     Accordingly, it is possible to effectively use the long ball screw  9  at the degree, and it is unnecessary to lengthen the long ball  9 . Therefore, it is possible to reduce a distance between the supports without further lengthening the long ball screw  9 . Further, since it is possible to increase a danger speed of the long ball screw  9 , it is possible to make a speed of the long ball screw  9  high. 
     Further, since the X-axis servo motors  29  and  31  are positioned near the ball screw  9  for the Y-axis and the intermediate support  57  is on the ball screws  21  and  23 , it is possible to reduce a vibration applied to the long ball screw  9  in the case that a vibration is generated at a time of punching such as in the punch press. 
     FIG. 10 shows the other embodiment in place of FIG.  9 . In FIG. 10, the same reference numerals are attached to the same elements as the elements in FIG. 9 and a detailed description will be omitted. In FIG. 10, a long ball screw spline  67  is used in place of the long ball screw  9 , and the long ball screw spline  67  is constituted by a spline portion  67 S and a ball screw portion  67 B. Further, a spline outer cylinder portion  71  is provided within the intermediate support main body  61  via a support bearing  69 . 
     Accordingly, the spline outer cylinder portion  71  is engaged with the spline portion  67 S of the long ball screw spline  67 . 
     In accordance with the structure mentioned above, when the ball screws  21  and  23  are rotated, the long ball screw  9  is rotated via the pulley  49 , the timing belt  53  and the pulley  45 ; and the pulley  51 , the timing belt  55  and the pulley  47 . Since the carriage  17  is moved in the direction of the X-axis via the nut member  15  when the long ball screw  9  is rotated, the workpiece W clamped by the work clamp  19  is moved in the direction of the X-axis. 
     In FIG. 5, when the ball screws  21  and  23  are rotated, the intermediate support main body  61  is moved, for example, in a rightward direction in FIG. 10 via the nut member  63 . At this time, the spline outer cylinder portion  71  is smoothly moved in the rightward direction with respect to the spline portion  67 S. As a result, the same effect as that in FIG. 9 can be obtained. 
     While preferred embodiments of the present invention have been described using specific terms, such description is for illustrative purpose, and it is to be understood that changes and variations may be made without departing from the spirit or scope of the following claims.