Structure for the packing of plunger pump

PURPOSE: A packing structure for plunger pump is provided to achieve an improved water tightness and pump efficiency and lengthen useful life of the pump by allowing the packing pressure to be automatically controlled. CONSTITUTION: A plunger pump(20) is configured in that a plurality of V-packings(8), a bush(10), a spring(12) and a suction valve(14) are sequentially arranged in a clearance(6) formed between a plunger and a cylinder(4), and packing support rings(16,18) are mounted at front and rear ends of the V-packing. Support rings, bush and spring have inner diameters slightly larger than the outer diameter of the plunger so as to avoid contact with the plunger. Packing support rings are made up of a material harder than that of the V-packing, and have V-shaped recesses and protrusions for coupling of the V-packing. The front support ring(16) gets caught at a protrusion(22) of the cylinder, and the rear support ring(18) contacts the rear end of the bush. The bush has a front groove(24) for insertion of the rear end of the spring, and the rear end of the spring contacts the suction valve.