초록 ▼

A hydraulic single piston pump for manual operation has a piston (3) with a first channel (14, 20) running from piston chamber (7) to the rod chamber (5). The first channel has a check valve (15-19) opening in the return stroke. The piston (3) also has at least one second channel (22, 23, 25) runnin

A hydraulic single piston pump for manual operation has a piston (3) with a first channel (14, 20) running from piston chamber (7) to the rod chamber (5). The first channel has a check valve (15-19) opening in the return stroke. The piston (3) also has at least one second channel (22, 23, 25) running from the piston chamber (7) to the rod chamber (5). The second channel is configured as a choke bore (23, 25) along at least a part of its length.

대표청구항 ▼

A hydraulic single piston pump for manual operation, comprising: a cylinder with an inlet and an outlet; a piston dividing said cylinder into a piston chamber and a rod chamber and being movable to decrease said piston chamber in a power stroke and to increase said piston chamber in a return stroke;

A hydraulic single piston pump for manual operation, comprising: a cylinder with an inlet and an outlet; a piston dividing said cylinder into a piston chamber and a rod chamber and being movable to decrease said piston chamber in a power stroke and to increase said piston chamber in a return stroke; a first channel extending through said piston from said piston chamber to said rod chamber; a check valve in and controlling fluid flow through said first channel, said check valve opening during the return stroke of said piston; and a second channel extending through said piston from said piston chamber to said rod chamber, said second channel having means for automatically controlling hydraulic fluid flow from said piston chamber to said rod chamber dependent on differential pressures in said chambers, said means including a first choke bore along at least as part of a length of said second channel.