| 摘要 |
<p>1469038 Bandsaws WURLITZER CO 31 Jan 1975 [25 March 1974] 4235/75 Heading B5L [Also in Division G3] Apparatus for cutting a workpiece 42 comprises X and Y table drives, the angle of the cutting blade 46 being conjointly controlled, to maintain it tangential to the direction of the cut, both for cutting, and for withdrawal of the blade. Servo systems controlling the drive motors 12, 30, 60 are made sufficiently sensitive to avoid contour errors due to servo lag ensuring that the blade can be backed out without fouling. Buffer storage (96), Fig. 3 (not shown), may be provided between a punched tape reader (92) and the main numerical control logic (100), the data rate from the buffer storage (96) to the logic (100) being at a higher rate than that at which the buffer receives the data from the reader, during circular interpolation of arcuate portions of the cut, the buffer accumulating such data during linear portions of the cut. Alternatively, the buffer may be omitted, and the data read from a disc store or mini-computer. The apparatus is a bandsaw for forming of piano keyboards from a single board, or wood blank, each key shape being that bounded by arcuate and linear cuts. The motor 60 controlling the blade orientation drives spiral gears 66, 68, belts; and pulleys 80, 82; 72, 74, 76, 78 controlling the orientation of blade guides 54, 56.</p> |
