Multi-cylinder hydraulic piston device, a cylinder therefor, and its method of making
US4799419A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Nov 9, 1983 |
| Grant date | Jan 24, 1989 |
| Priority date | — |
| Expiry date | Nov 9, 2003 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF05C2253/12
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
A cylinder block for a multi-cylinder hydraulic or hydrostatic piston device is provided having a control layer comprising a sintered friction metal layer sintered onto the cylinder block under the simultaneous action of pressure and heat. The end surface of the cylinder block is first provided with an electrodeposited metal layer. The electrodeposited layer has a crystal lattice constant compatible with the sintered layer and the material of the cylinder block. The cylinder block is preferably made from steel or aluminum and the electrodeposited layer is preferably copper or nickel. After the friction metal layer, preferably bronze, is sintered onto the electrodeposited layer, the cylinder block is treated to improve the strength and wear characteristics of the cylinder block without injuring the sliding friction characteristics of the sintered friction metal layer. In the case of steel, the preferred treating process is gas nitriding, and in the case of aluminum or an aluminum alloy, the preferred treating process is anodizing.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.