Method of cutting off workpiece using band saw machine as well as band saw machine

Abstract

In a cutting-off method, when a workpiece is to be cut off by use of an endless band saw blade suspended between a driving wheel and a driven wheel, the workpiece is cut off by imparting to the driving wheel a forced oscillation so that a phase of an oscillation of the driving wheel along its rotational direction is substantially inverted with respect to a phase of an oscillation of the driven wheel along its rotational direction. In addition, pulses can be applied to a driving motor for rotationally driving the driving wheel in order to cause the driving wheel to oscillate along its rotational direction.

1 . A method of cutting off a workpiece using a band saw blade, the method comprising:
 cutting off a workpiece by an endless band saw blade suspended between a driving wheel and a driven wheel, by imparting to the band saw blade a forced oscillation so that a phase of a longitudinal oscillation which occurs to the band saw blade near the driving wheel is substantially inverted with respect to a phase of a longitudinal oscillation which occurs to the band saw blade near the driven wheel.   
   
   
       2 . The method of cutting off a workpiece according to  claim 1 , further comprising:
 applying pulses with a frequency not less than a characteristic frequency of a band saw blade supporting system to a motor for driving the driving wheel, so that the phase of the longitudinal oscillation which occurs to the band saw blade near the driving wheel is substantially inverted with respect to the phase of the longitudinal oscillation which occurs to the band saw blade near the driven wheel.   
   
   
       3 - 6 . (canceled) 
   
   
       7 . A method of cutting off a workpiece using a band saw blade, the method comprising:
 cutting off a workpiece by an endless band saw blade suspended between a driving wheel and a driven wheel, by imparting to the band saw blade a forced oscillation so that a phase of an oscillation which occurs to the band saw blade in a main-component-force direction near the driving wheel is substantially inverted with respect to a phase of an oscillation which occurs to the band saw blade in the main-component-force direction near the driven wheel.   
   
   
       8 . The method of cutting off a workpiece according to  claim 7 , further comprising:
 applying pulses with a frequency not less than a characteristic frequency of a band saw blade supporting system to a motor for driving the driving wheel so that the phase of the oscillation which occurs to the band saw blade in the main-component-force direction near the driving wheel is substantially inverted with respect to the phase of the oscillation which occurs to the band saw blade in the main-component-force direction near the driven wheel.   
   
   
       9 . A band saw machine which cuts off a workpiece by use of an endless band saw blade suspended between a driving wheel and a driven wheel, the band saw machine comprising:
 an oscillation imparter that imparts, to the band saw blade, a forced oscillation so that a phase of an oscillation which occurs to the band saw blade in a main-component-force direction near the driving wheel is substantially inverted with respect to a phase of an oscillation which occurs to the band saw blade in the main-component-force direction near the driven wheel.   
   
   
       10 . A method of cutting off a workpiece using a band saw blade, the method comprising:
 cutting off a workpiece by an endless band saw blade suspended between a driving wheel and a driven wheel, by imparting to any one of the driving wheel and the driven wheel a forced longitudinal oscillation so that a phase of an oscillation of the driving wheel along a rotational direction of the driving wheel is substantially inverted with respect to a phase of an oscillation of the driven wheel along a rotational direction of the driven wheel.   
   
   
       11 . (canceled) 
   
   
       12 . Making the method of cutting off a workpiece according to  claim 10 , further comprising:
 making the band saw blade oscillate in a main-component-force direction by causing any one of the driving wheel and the driven wheel to forcedly oscillate along its rotational direction so that the ratio between the amplitude of the oscillation which occurs to the band saw blade near the driving wheel and the amplitude of the oscillation which occurs to the band saw blade near the driven wheel is approximately equal to one.   
   
   
       13 . A method of cutting off a workpiece using a band saw blade, the method comprising:
 cutting off a workpiece by an endless band saw blade suspended between a driving wheel and a driven wheel, by forming a node of oscillation in a main-component-force direction between the driving wheel and the driven wheel by imparting to the band saw blade a forced longitudinal oscillation so that a phase of an oscillation which occurs to the band saw blade in the main-component-force direction near the driving wheel is substantially inverted with respect to a phase of an oscillation which occurs to the band saw blade in the main-component-force direction near the driven wheel, whereby a frictional chatter oscillation is blocked in a section where the node is formed, and whereby the frictional chatter oscillation is restrained while the workpiece is being cut off.   
   
   
       14 . A method of cutting off a workpiece using a band saw blade, the method comprising:
 cutting off a workpiece by an endless band saw blade suspended between a driving wheel and a driven wheel, by generating a node in a longitudinal direction of a forced longitudinal oscillation which is imparted to the band saw blade in a substantially central section of a width with which the workpiece is cut off.   
   
   
       15 . A band saw machine which includes an endless band saw blade suspended between a driving wheel and a driven wheel, the band saw machine comprising:
 a motor which rotates the driving wheel; and   a forced oscillation imparter which imparts, to the driving wheel, an oscillation so that a phase of an oscillation of the driving wheel along a rotational direction of the driving wheel is substantially inverted with respect to a phase of an oscillation of the driven wheel along a rotational direction of the driven wheel.   
   
   
       16 . A method of cutting off a workpiece using a band saw blade, the method comprising:
 cutting off a workpiece by an endless band saw blade suspended between a driving wheel and a driven wheel, by forming a node of a longitudinal oscillation of the band saw blade between the driving wheel and the driven wheel by imparting to the band saw blade a forced longitudinal oscillation so that a phase of a longitudinal oscillation which occurs to the band saw blade near the driving wheel is substantially inverted with respect to a phase of a longitudinal oscillation which occurs to the band saw blade near the driven wheel, whereby a frictional chatter oscillation is blocked in a section where the node is formed, and whereby the frictional chatter oscillation is restrained while the workpiece is being cut off.   
   
   
       17 . The method of cutting off a workpiece according to  claim 16 , further comprising
 cutting off the workpiece by generating the node in a longitudinal direction of the forced longitudinal oscillation which is imparted to the band saw blade in a substantially central section of a width with which the workpiece is cut off.