Straightening and cutting-off machine

Abstract

A straightening and cutting-off machine for the production of straightened elements of predeterminable length from a wire-shaped material, in particular for the production of straightened bars from reinforced-concrete steel wire, has a feed device for drawing in material from a material stock, a preferably rotating straightening device for straightening the material conveyed into a working range of the straightening device by the feed device, a cutting device, following the straightening device, for separating a portion of predeterminable length from the straightened material to produce the straightened element, a length measurement system for measuring the length of the material and for generating a measurement signal representing the length, and a control device for activating the cutting device on the basis of the measurement signal. The measurement system is a contactlessly operating optical measurement system, in particular a laser measurement system, which allows length measurement continuously with high measurement accuracy even at high run-through speeds.

1 . A straightening and cutting-off machine that produces straightened elements of predeterminable length from a wire-shaped material comprising:
 a feed device that draws in material from a material stock;   a straightening device that straightens the material conveyed into a working range of the straightening device by the feed device;   a cutting device, following the straightening device, that separates a portion of a predeterminable length from the straightened material to produce the straightened element;   a contactlessly operating length measurement system that measures length of the material and generates a measurement signal representing the length; and   a control device that activates the cutting device on the basis of the measurement signal.   
     
     
         2 . The machine according to  claim 1 , wherein the measurement system comprises a device that generates at least one laser beam directed onto the material and devices that detect interaction between the laser beam and a surface of the material. 
     
     
         3 . The machine according to  claim 2 , wherein the laser measurement system operates according to the laser Doppler principle. 
     
     
         4 . The machine according to  claim 2 , wherein the laser beam impinges onto the surface of the material in a radiation direction running transversely with respect to a run-through direction of the material. 
     
     
         5 . The machine according to  claim 4 , wherein the laser beam impinges onto the surface of the material such that an angle between a radial direction to the run-through direction and a radiation direction is less than about 30°. 
     
     
         6 . The machine according to  claim 1 , wherein the straightening and cutting-off machine has an operator side and an operator-remote side, and wherein the laser beam impinges onto the material from the operator side. 
     
     
         7 . The machine according to  claim 2 , wherein run-through direction of the material lies in a vertical plane, and wherein a radiation direction of the laser beam forms with the vertical plane an angle of less than about 45°. 
     
     
         8 . The machine according to  claim 7 , wherein the laser beam impinges onto the surface of the material from above. 
     
     
         9 . The machine according to  claim 1 , wherein the feed device comprises a pair of draw rollers arranged downstream of the straightening device and rotatable contradirectionally about parallel axes of rotation, and a measuring head of the measurement system is arranged between the draw rollers and the cutting device. 
     
     
         10 . The machine according to  claim 9 , wherein one of the draw rollers is mounted fixedly with respect to the machine, and another draw roller is displaceable in a lifting-off direction running substantially perpendicularly with respect to the axis of rotation, counter to the force of a press-down device, and wherein the measurement system generates a laser beam such that a radiation direction of the laser beam forms with a lifting-off direction an angle of less than about 45°. 
     
     
         11 . The machine according to  claim 10 , wherein the angle is less than about 20° 
     
     
         12 . The machine according to  claim 10 , wherein the laser beam impinges onto the material from above. 
     
     
         13 . The machine according to  claim 1 , wherein the straightening device comprises a rotary-driveable straightening mechanism. 
     
     
         14 . The machine according to  claim 1 , wherein the cutting device comprises a pair of contradirectionally rotatable cutting-tool carriers. 
     
     
         15 . The machine according to  claim 1 , which produces straightened bars from reinforced-concrete steel wire. 
     
     
         16 . A straightening and cutting-off machine that produces straightened elements of predeterminable length from a wire-shaped material comprising:
 a feed device that draws in material from a material stock;   a straightening device that straightens the material conveyed into a working range of the straightening device by the feed device;   a cutting device, following the straightening device, that separates a portion of predeterminable length from the straightened material to produce the straightened element;   a length measurement system that measures length of the material and generates a measurement signal representing the length and comprises a laser measurement system having a device that generates at least one laser beam directed onto the material and devices that detect interaction between the laser beam and a surface of the material, wherein the laser beam impinges onto the surface of the material from above such that an angle between a radial direction to a run-through direction of the material and a radiation direction is less than about 30°; and   a control device that activates the cutting device based on the measurement signal.   
     
     
         17 . The machine according to  claim 16 , wherein the feed device comprises a pair of draw rollers arranged downstream of the straightening device and rotatable contradirectionally about parallel axes of rotation, and a measuring head of the measurement system is arranged between the draw rollers and the cutting device directly downstream of the draw rollers. 
     
     
         18 . The s machine according to  claim 17 , wherein the draw rollers each comprise a concave circumferential contour so that, in a region of greatest approach of the draw rollers, a guide orifice with lateral guidance for the straightened material is formed. 
     
     
         19 . The machine according to  claim 17 , wherein the measuring head is fastened to a front side, facing the draw rollers, of an intermediate wall mounted fixedly with respect to the machine such that the measuring head is nearer to the draw rollers than to the cutting device, and the intermediate wall comprises a passage orifice for the material. 
     
     
         20 . The machine according to  claim 19 , wherein a position of the measuring head on the intermediate wall can be set via adjusting screws.