Variable piston pumps for single-acting vane pumps, radial or axial piston pump gear pump and double acting vane pump for dosing pumps are generally variable pump specializing in complex structures (variable pump), the price is high;. Variable plunger pump outlet pressure by a feedback mechanism to control the swash plate angle refinement (variable pump), thereby controlling the stroke of the plunger was to achieve the purpose of flow control; variable vane pump outlet pressure by a feedback mechanism to control the amount of eccentricity eccentric ring to achieve the purpose of controlling the flow of ; that is to say, when the variable swash plate plunger vertical flow is zero, vane pump empathy. Pump itself can be "positive and negative", it depends on the direction of the swash plate two swings for the job outside of the casing of the pump control module must have variable traction swash plate. As long as the amount of external control some adjustment. Easily complete the swash adjust the angle made such a variable displacement pump is inevitable. motors (or other power source) forward and reverse rotation maintenance (variable pump) phones, two-way rotary pump drive, complete back into the oil. Because of their own high-power motor rotation inertia great, can not be quickly brake, reverse, so this approach is only suitable for small power motors (such as large valve opening and closing mechanism), or commutation infrequent systems (such as opening and closing mechanism grabs the port). Maintenance ( variable pump) _ variable hydraulic pump _ from Jinan Jing Jing Chong Chong Hydraulic Machinery Limited. Jinan Jing Chong Hydraulic Machinery Co., Ltd. (www.jnjcyy.com) (www.jnjcyy.com) strong, credible, in Jinan, Shandong mining machinery industry has accumulated a large number of loyal customers. The company better work attitude and continuous improvement to create innovative ideas will lead crystal hydraulic and you hand into the brilliant, for a better future!