| 摘要 |
<p>A valve unit (24) comprises an electromagnetically operated off valve (15) and a pressure-limiting valve (21). The shutoff valve is constituted by a first closure member (46) cooperating with a first valve seat (59) on a second closure member (47) which has a passage therethrough and the pressure-limiting valve (21) is constituted by the second closure member cooperating with a second valve seat (55), fixed relative to the housing, under the action of a spring (49). The initial stressing force of the spring (49) is greater than the closing force exerted on the first closure member (46) by an armature (36), and the second closure member (47) is moved away from its seat (55) only in response to a pressure differential across that member. The valve unit, when used in a motor vehicle hydraulic brake system having an anti-skid and drive slip control device, is connected via passage (70) to a wheel brake and via passage (69) to a master cylinder. <IMAGE></p> |
