| 摘要 |
There is indicated a programmable braking device for the X guide block (18) and the Y guide block (30) of a drafting machine which comprises a brake band (42, 60) which is moved together with the considered guide block. The band revolves around guide pulleys (38, 40; 62, 64), which are arranged laterally outside the displacement path, and is lockable by an associated magnetic brake (44-58; 70-76). In a modified programmable braking device, the guide block (30) carrying the drafting head carries two direction brakes (130, 132) for the two co-ordinate directions. These brakes each comprise a freely running belt conveyor which is movable against the drawing surface in a friction grip.
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