shirindaburotsuku structure null of baransashiyahuto attaching

摘要

PURPOSE:To reduce the size of an engine and to ensure rigidity required for a cylinder block by supporting a pair of balancer shafts on the forward end, middle and trailing end bearing portions and storing same inside the respective side walls in a cylinder block body. CONSTITUTION:A pair of balancer shafts 20A, 20B respectively having a balance weight portion 23 are disposed inside the lower portions of the respective side walls 12A, 12B in a cylinder block body 10. In this case, the forward end and middle journal portions 21, 24 of the balancer shafts 20A, 20B are supported by the forward end and middle bearing portions 31, 32, and the tailing end journal portion 26 thereof is supported by a trailing end bearing portion 33 projected from the respective side walls 12A, 12B through bearing metals 31a-33c, respectively. The respective bearing portions 31-33 are connected by ribs 35-37 formed on bulk heads 17a, 17c, 17d.