摘要 |
PURPOSE:To enhance strength and durability of a cylinder by using the internal cylindrical surface of wire coil as the slide surface with the piston, embedding its external cylindrical surface in a cast base material, and therby making the cylinder light in weight. CONSTITUTION:Round the outside surface of a cylindrical core 4, a thin metal wire 1 of 0.1-5mm. in diameter consisting of piano wire, mild or hard steel wire is wound to form a coil 2, where some necessary points are metallized with aluminum or iron with a metallization gun, and the starting and finishing ends are provisionally welded to the adjoining metal wires. It may be selected also such a process that the coil 2 is dipped in a bath of aluminum zincate etc. to form a plated layer and the coil wires are fixed to each other. The coil 2 thus formed is put in a casting form together with the core 4, and molten material such as aluminum (ADC 12) is poured in. The liner surface is finished into a desired diameter by boring or honing. Coil 2 can provide a good pressure resistance and a sufficiently thin wall thickness. Provision of a number of circumferential grooves ensures that the lubricating oil is surely reserved. |