| 摘要 |
<p>A load-sensing and pressure-limiting device is disclosed for fluid-driven appliances having at least two fluid-driven working motors, in which the load on a first working motor is variable by operating one or more other working motors, wherein a pressure proportional to the load on the first working motor is sensed by the device and used to avoid overloading of the first working motor. The sensing device has a primary piston with smaller cross-sectional area, intended to sense the load on the first working motor, and a secondary piston with larger cross-sectional area, both pistons being displaceable in a cylinder having two slots of different cross-sectional area, corresponding to said area of the pistons, to a tripping position where one or more ports communicating with the fluid pipes of the one or more other working motors are opened, whereby the fluid pressure applied to these other working motors can act upon the secondary piston and move it further in tripping direction.</p> |
