Transfer apparatus having vacuum holes and method of making such apparatus
US5006900A · kind A · utility
12Cited by
10References
10Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jul 3, 1989 |
| Grant date | Apr 9, 1991 |
| Priority date | — |
| Expiry date | Jul 3, 2009 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB23K2103/50
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
A transfer apparatus includes a transfer member, for example, a transfer drum with a line of small closely spaced laser drilled vacuum holes to hold a receiving sheet to the drum surface. To maintain the continuity of a transfer field but be free from clogging, the holes are narrow near the surface of the drum but wider as they extend deeper in the drum. Conical holes are drilled in the drum by a laser. In one embodiment, a short focal length lens focuses a laser bear near the surface of the drum which beam spreads below the surface to form a conical hole.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.