| 摘要 |
<p>1,168,020. Milling tools. FORD MOTOR CO. Ltd. 24 Sept., 1968 [3 Oct., 1967], No. 45221/68. Heading B3K. [Also in Division B5] A tool for cutting soft materials such as clay and polystyrene for forming models has a closed loop cutting edge which lifts the material from the model without build-up and which can be heated or cooled. As shown, the cutter loop 56<SP>1</SP> is integrally formed with two metal shanks 36<SP>1</SP> insulated from each other by insulant 42<SP>1</SP> and joined by a metal bridge 60. The shanks 36<SP>1</SP> are mounted on insulant pieces 32<SP>1</SP>, 34 in a spindle 14<SP>1</SP> rotatably mounted in spindle housing 10<SP>1</SP>. A tube 58<SP>1</SP> passes through the insulant 42<SP>1</SP> and cooling fluid is supplied to and removed from cavity 26<SP>1</SP> in the spindle 141 via tubes 28<SP>1</SP> and 301. An induction coil 54<SP>1</SP> surrounds the cutter between the spindle 14<SP>1</SP> and the cutter loop 56<SP>1</SP> and is mounted on the spindle housing 10<SP>1</SP>. The induction loop is formed by the loop cutter 56<SP>1</SP>, shanks 36<SP>1</SP> and bridge 60 and is thinnest at point P on the loop so that maximum heating occurs there. The temperature to which the cutter is heated can be varied both by varying the induced current in the induction loop and by passing a refrigerant gas such as air or carbon dioxide down tube 58 and on to the cutter. When used for cutting clay, the cutter is preferably cooled to a temperature below ambient by using a refrigerant only.</p> |
