| 摘要 |
<p>The method for regulating the delivery of a positive displacement pump with automatic inlet (5) and outlet valves (6) is based on keeping an inlet valve open during an adjustable part of the working stroke of the pump pistons (2). The amount of liquid flowing out through the open inlet valve during this stroke is used to operate a piston (14) or similar element which is connected with the valve such that the distance the piston (14) has to travel to close the valve is adjustable. This may be achieved by having the piston (14) slidable in a cylindrical bush (12) with perforated wall which is contained in the pump intake duct (9) such that the liquid flows through the perforation to the pump cylinder (1), a slide (13) being provided to shut off part of the perforation at will.</p> |
