Abstract: A volumetric feeder may comprise a driving unit, a storage tank, a sealing unit, a switch unit and a feeding unit. An interior space of the storage tank is horizontally divided into a feeding space and a preparing space which have the same volume such that the feeding material, including viscous or cement-like materials, in the preparing space is configured to be transported into the feeding space with the same volume at a time to achieve volumetric feeding effect. Also, the feeding material in the feeding space is moved by a piston in a pushing manner thus preventing the feeding material from damage or heating during feeding process.

Abstract: A sewing machine includes a main frame, a retainer, a rocker arm assembly, a wire assembly, and a platform. The main frame contains therein a transmission mechanism. The retainer is mounted to the base of the main frame. The retainer defines a bore in which a first gear transmission assembly is received. A rocker arm retaining disk assembly is mounted on the bore. The rocker arm assembly includes a rocker arm body which forms a plurality of bent sections which is configured to have the thread engaging device opposing the main frame. The platform is mounted to the base of the main frame.