| 摘要 |
A speed meter measures low range speeds such as feed speeds on a machining devices. Ultrasonic waves are radiated against a mobile object performing a linear displacement with respect to a detection head, and ultrasonic waves reflected by the mobile object are used for controlling the state of a pair of signal gating elements. Clock pulses passed to the elements are gated over different periods phased from each other by an operation interval which can be adjusted depending on the process conditions. Distances between the detection head and the mobile object in the different periods are specified by count values obtained from the results of respective gating, and the average speed of the linear displacement of the mobile object is calculated on the basis of these count values. Digital mode processing of the signals simplifies the construction and lowers the production cost. Use of ultrasonic waves avoids negative influences caused by the state and configuration of the face of the mobile object, thereby enabling a wide range of application.
|
