| 摘要 |
PURPOSE:To deliver plural pieces of forward and backward revolution information in a cycle of an output pulse with a simple constitution, by latching with two steps the output of a pulse encoder to form an address and then reading out the forward and backward revolution information from a storage means. CONSTITUTION:The waveform is shaped for output pulses PA and PB of a pulse encoder which have a shift of phases and the phase relation reversed between the forward and backward revolutions of a wheel. These output pulses are processed by a double-stage latch circuits 13 and 16 as well as 14 and 17. The addresses are formed with the outputs of these latch circuits, and an access is given to an ROM15. Therefore, for instance, the forward revolution information D1 of a high level is delivered in the case of an address excepting 1000 and synchronizes with a clock PC in response to 2-bit signals AD4, AD5, etc. which control the ROM15. Then plural pieces of forward revolution information are delivered up to 4 units, etc. in a cycle of the pulse PA. The same applies to the backward revolution information. In such a way, plural pieces of forward/backward revolution information are produced in a cycle of an output pulse of an encoder with a simple constitution of a reduced number of component parts. This improves the detecting resolution. |
