The weighing and checking machine mainly accomplishes the acquisition of signals and sends the weight signal to the controller for processing. In order to make sure that only one product passes through the weighing table during the working process, so the speed of the feeding conveyor is jointly decided according to the spacing of the products and the required speed. During the weighing process, when the product to be inspected passed by the assembly line enters the weighing conveyor, the system recognizes the product to be inspected as entering the weighing zone according to the external signal. By means of the running speed of the weighing conveyor and the length of the conveyor, or the level signal, the system determines the time when the product leaves the weighing conveyor. From the time the product enters the weighing platform to the time it leaves the platform, the load cell transmits the detected weight signal to the controller, which selects the signal from the signal stabilization area for processing to obtain the weight of the product.