| 摘要 |
<p>1325497 Feed control SIEMENS AG 22 Sept 1970 [23 Sept 1969] 45175/70 Addition to 1216000 Heading B3B [Also in Division G3] In a lathe, the tool traverse and/or the depth of cut is reduced until the spindle torque exceeds an upper threshold, and in-feed is carried out up to a maximum of the programmed contour as long as the torque undershoots a lower threshold, the vibrations of the tool and/or workpiece being measured during machining, and compared with a theoretical value, and in dependance on the difference determined by this comparison, the feeds in the X and Z directions, determined by a control system from the cutting performance can be corrected. In a lathe 1, a workpiece 2 is machined by a tool 3, and the lathe is controlled by a numerical control system 6, in which the feeds in the Z and X directions are determined from the measured cutting performance. The spindle torque is measured, and multiplied by the spindle speed, and this cutting factor is compared with a theoretical cutting factor P zs or P xs . The latter factor in many cases does not correspond to the maximum of which the machine is capable, due to vibrations. If the vibrations of the tool picked up from tool mounting 4 by an accelerometer or vibration measuring device 5, correspond in their amplitude A zi and A xi , to theoretical factors A zs and A xs , the output from amplifiers 11, 12, will be zero, and the value fed to feed controllers 7, 8, will correspond to the maximum value set up in potentiometers 9, 10. If the amplitude of vibration rises, the voltage across potentiometers 9, 10, and therefore the theoretical machining factor P xs , P zs , will drop. Instead of analysing the signal from tool 3, the signal from the spindle torque can be analysed.</p> |
