| 摘要 |
<p>The invention relates to a hydraulic circuit for the (sequential) control of two of more hydraulic cylinders, more particularly for opening and closing the folding roof with a vehicle of the cabriolet type, in which the cylinder space under the piston (c,B,A,a) of each piston cylinder device is selectively connectable to a hydraulic pressure source (8) or to a reservoir for hydraulic fluid (9), an additional valve (12) device being provided, by means of which the cylinder space above the piston is also connectable to the pressure source (8) for at least a part of the piston cylinder devices. According to the invention the cylinder spaces above the pistons are hydraulically connected and said additional valve (12) device is constituted by a common electrically operated valve for the piston cylinder devices, by means of which the cylinder spaces above the pistons are jointly connectable to either the pressure source (8) or the reservoir (9). <MATH></p> |
