Micro-weighing method of injection pump

The invention discloses a trace weighing method of an injection pump, which comprises the following steps: step 1, a preparation step: preparing a balance, a to-be-detected injection pump, a hard tube, a sampling needle, a test tube containing clear water and a driving motor device, and driving the to-be-detected injection pump to perform slow suction and quick discharge actions by the driving motor device; step 2, controlling the tip of the sampling needle to penetrate through the closed cavity and extend 3-5mm below the liquid level of the test tube; 3, when the balance reading is stable, zero clearing is carried out, the injection pump to be tested is controlled to discharge or suck the required test amount through a driving motor device according to the test requirement, the rotating speed of the driving motor device is 4-6 revolutions, and after the balance reading is stable, the balance reading is recorded to obtain weighing data; and 4, continuously weighing for more than 8 times according to the step