Abstract: The total weight of a plurality of resin products is set as a reference value, and a first upper-limit threshold and a first lower-limit threshold are respectively stored in a control circuit 38 on the upper limit side and the lower limit side with respect to the reference value. A second upper-limit threshold which is yet greater than the first upper-limit threshold and a second lower-limit threshold which is yet smaller than the first lower-limit threshold are stored in the control circuit 38. When the total weight of the resin products is greater than the first upper-limit threshold, a determination is made by the control circuit 38 as to whether or not the total weight of the resin products is yet greater than the second lower-limit threshold. Further, when the total weight of the resin products is less than the first upper-limit threshold, a determination is made by the control circuit 38 as to whether or not the total weight of the resin products is yet less than the second lower-limit threshold.

Abstract: An apparatus for measuring the weight of a molded resin article in conjunction with an injection molding cycle and judging whether the molded article is acceptable or rejective. A belt conveyor is provided below a mold for injection molding. Articles (connector housings) molded with the mold are dropped out of the mold onto the belt conveyor when the mold is opened, and transported to a weight checker by means of the belt conveyor. In the weight checker, the weight of the transported articles is measured. The measured weight is compared with a predetermined reference weight. If the measured weight is within a predetermined permissible range with respect to the reference weight, it is judged that the molded articles are acceptable, and then the molded articles are dropped into an acceptance box.