抄録
Recently, electro-hydraulic servosystems have come to be applied widely to systems like material testing and vibration testing equipment.
The bandwidth of these systems is required to be broader than 100Hz.
The spool valve servomotor, which plays an important role in the above mentioned systems, is also required high frequency response.
We have often experienced some problems of the servomotor peculiar to the high frequency region, such as self-excited oscillation of the spool valve.
On the other hand, to the authors' knowledge, there have been few published papers covering both theoretical and experimental research on the dynamic characteristics of the servomotor in the frequency region much higher than 100Hz.
The purpose of this present research is to make clear the high frequency characteristics of the servomotor, not only theoretically but also experimentally.
Theoretical results, given in a form of a distributed parameter system, fairly well coincide with the experimental ones.
Numerical calculation of the theoretically given characteristics is so complicated that an approximated frequency transfer function is derived. By the use of this function, the general trend of the frequency characteristics of the servomotor is investigated.
From the results of the theoretical and experimental research, it becomes clear that in order to obtain a servomotor having high frequency response, attention must be paid in designing not only to the dimensions of the conduits but also to the magnitude of the valve and cylinder chambers.
