| 摘要 |
PURPOSE:To achieve constant horsepower or long lamp Pc control, nearly equal to to the theortical value and without causing any change in the characteristics of said control due to change in varying moment, by actuating a control mechanism for regulating the displacement of a variable control element by means of another control pressure forming mechanism. CONSTITUTION:Control pressure PF, controlled by a first variable orifice 24 formed between control piston 21 and control spool 22, is acted in back chamber 25 of control piston 21, so that influence of the moment acted to swash plate 11 is eliminated by thus making control pressure PF cope with the varying moment exerted by spring 13. Therefore, if there is caused change in the varying moment acted to swash plate 11, displacement of swash plate 11 is not caused since control pressure PF in back chamber 25 is regulated automatically in response to the change in the varying moment. That is, it is enabled to ahcieve constant horsepower or long lamp Pc control nearly equal to the theoretical value, since characteristics of the above control is not changed by the change in the varying moment. |
