Pumping apparatus for delivering liquid at high pressure

  • US 4,883,409 A
  • Filed: 09/19/1988
  • Issued: 11/28/1989
  • Est. Priority Date: 09/26/1987
  • Status: Expired due to Term
First Claim
Patent Images

1. Pumping apparatus for delivering liquid at a high pressure, comprising:

  • a. a first piston (10) for reciprocation in a first pump chamber (7), the first pump chamber having an inlet port (9) and an outlet port,b. a second piston (20) for reciprocation in a second pump chamber (18), the second pump chamber having an inlet port (9'"'"') and an outlet port,c. a conduit connection (12,14) between the outlet port of the first pump chamber and the inlet port of the second pump chamber,d. an inlet valve (4) connected to the inlet port of the first pump chamber for allowing flow of liquid into the first pump chamber and for inhibiting flow in the opposite direction,e. an outlet valve (13) connected to the outlet of the first pump chamber for allowing flow of liquid into the second pump chamber and for inhibiting flow in the opposite direction,f. drive means (30,34;

    31,33;

    32,36) for reciprocating the first and the second piston, comprising ball-screw spindles (30,31) coupled to each of said pistons (10,20), respectively, and said drive means for each piston further comprising;

    an actuating element (37) having a recess (38) for receiving a ball (27),a ball (27) having such a diameter that it projects above the recess (38), but can freely move inside the recess,a piston holder (25) to which the piston (10) is mounted having a surface for contacting the ball (27),a return spring (15) for exerting a force on the piston (10) in a direction away from the pump chamber (7), and a guiding element (39) arranged between the actuating element (37) and the pump chamber (7) for guiding the piston (10), andg. control means (41,42,43,44,35) coupled to the drive means (30,34;

    31,33;

    32,36) for adjusting the stroke lengths of the pistons (10,20) between their top dead center and their bottom dead center, respectively, thereby permitting an adjustment of the amounts of liquid displaced by the first and second piston, respectively, during a pump cycle such that pulsations in the flow of the liquid delivered to the output of the pumping apparatus are reduced.

View all claims
    ×
    ×

    Thank you for your feedback

    ×
    ×