Abstract: An internal calibration mechanism of a weigh module has a driving structure, a calibration weight and a weight support frame. The weight support frame has an opening or a groove for loading the calibration weight. The weight support frame is connected to a load receiving portion at both sides thereof and is connected to a portion of a fixing portion that extends towards the load-receiving portion. In one case, the weight support frame, the load-receiving portion and the fixing portion are integrally formed. In another case, a force transmission connecting portion and a fulcrum connecting portion of the weight support frame are fixedly connected, respectively, to the load-receiving portion and to the extending portion of the fixing portion. In another case, flexure hinges connect the weight support frame to the load-receiving portion at both sides thereof and connect the weight support frame to the extending portion.

Abstract: A weighing sensor is provided for an electronic balance. A weighing unit of the weighing sensor has a load-receiving portion, a fixing portion, and parallel guiding members that connect the load-receiving and fixing portions A lever, with a first end connected to the load-receiving portion, is located between the parallel guiding members and the fixing portion. A lower portion of a photoelectric position limiting block is connected to the fixing portion, and an upper portion thereof has a limiting structure. A tail end portion of a second end of the lever is disposed in the limiting structure, limiting its deviation. The photoelectric position limiting block has a photoelectric position sensor and a stop structure for limiting deviation of the tail end portion.

Abstract: A weighing sensor and a lever are disclosed. The weighing sensor has a load-receiving portion, a fixing portion, and a parallel guiding portion connected to the load-receiving portion and the fixing portion. The parallel guiding portion has upper and lower parallel guiding units, separated from each other. The ends of the parallel guiding units are connected to the load-receiving portion and the fixing portion. The fixing portion has an extension located between the parallel guiding units. The extension is at a distance from both parallel guiding units and extends to the load-receiving portion. A gap is formed between the extension and the load-receiving portion; and the distance between the extension and the upper parallel guiding unit allows a lever to pass through. The weighing sensor has a simple structure, both the processing process and the assembly process are simplified, and the processing and assembly during production are facilitated.