| 摘要 |
PURPOSE:To detect the stopping position of a carriage, by setting the space between a pair of position sensors to be slightly shorter than the length of the carriage in the transferring direction thereof so that outputs are overlappedly delivered from the pair of sensors. CONSTITUTION:Transmission holes 10a... are formed in a slit plates 10 which is attached to a pallet 1 and which has a length equal to the length L of the pallet 1 in the transfer direction of the latter. Meanwhile, a pair of photoswitches 11, 12 are arranged along a conveyer path with a certain distance (l) therebetween which is slightly shorter than the length L. The outputs of sensors 15, 16 become high during periods between times t0, t2 and between times t1, t3 at which the pallet 1 passes, and therefor the photoswitches delivers pulse signals. When the pallet 1 advances on the conveyer path and then enters into the speed detection area, an OR gate 19 delivers a pulse signal which is converted into a voltage signal by means of a converter 20, thereby the pallet 1 is decelerated in association with the voltage signal. When the pallet 1 has come to the center of the speed detection area, the output (e) of an AND gate becomes high so that the pallet 1 is stopped by means of a magnet.
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