| 摘要 |
<p>1413926 Reciprocating pumps WAGGON UNION GmbH 30 April 1974 [14 May 1973] 18935/74 Heading F1A A quick-acting pump for operating an emptying valve of a railway tank wagon comprises a spring- loaded piston 1 engaged by two eccentrics 2a, 2b angularly displaced relative to one another on a common driving-shaft 3 operated by hand wheels 5. In the rest position of the pump, the piston spring-loading biases the eccentrics into their Fig.3 position, so that whichever direction a hand wheel is rotated one of the eccentrics will effect a piston discharge stroke. Rotation of the shaft 3 is limited by pins 25 parallel to the respective directions of eccentricity of the eccentrics and engageable with abutments 26 to limit movement of the eccentrics to a position just beyond their respective top dead centre positions, to hold the piston at the end of its discharge stroke, initial return movement of the hand wheel then starting the return stroke which is completed by the piston spring. Plug-in couplings 4 connect the hand wheels 5 to shaft 3. The pump cylinder (7), Fig.2 (not shown), communicates with a reservoir (10) via a port 9 which may or may not have a non- return valve.</p> |
