Renewable nut for a lead screw drive and method of making same
US4292722A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Aug 13, 1979 |
| Grant date | Oct 6, 1981 |
| Priority date | — |
| Expiry date | Aug 13, 1999 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T82/2549
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
In a lead screw drive, such as that used in a lightweight lathe or milling machine for driving the workpiece relative to the cutting tool, the core of a drive nut is made of a material having a relatively low melting temperature, such as babbitt metal or a relatively rigid thermoplastic material. The low melting point material is contained within a nut housing as of steel. The openings in the nut housing for passage of the lead screw are scaled in a fluid type relation by means of elastic sealing members as of silicone rubber having a melting point above that of the relatively low melting point core portion of the nut. An electrical heating cartridge element is contained within the nut housing in good thermally conductive relation with the low melting point core material. When backlash develops due to wear of the core material of the nut, the heating element is energized under control of a controller to melt the core of the nut so that the core material is caused to flow and to reform itself to the thread profile of the lead screw. A thermocouple disposed in thermally conductive relation with the core senses the temperature of the core. A controller responsive to the sensed tempera…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.