Method and apparatus for machine safety
US4660703A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 6, 1984 |
| Grant date | Apr 28, 1987 |
| Priority date | — |
| Expiry date | Nov 6, 2004 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB21D55/00
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
The present invention discloses both a safety sensing system and a method of providing safety protection for presses or like industrial machines having a reciprocally movable operating head, ram, tool or beam. The basis of the system is the provision of a first beam (or a plurality of first beams) each of which is placed across and in front of the intended direction of travel of the pressing tool or blade. A second beam is arranged in the intended direction of travel and is broken by the tool or blade when the latter has reached a predetermined minimum height above a workpiece. A control system is provided which, during the operating stroke of the blade retracts the blade if any one or more of the first beam(s) is or are broken but the second beam is not broken. However, once the second beam is broken, the stroke of the blade is completed even if the first beam(s) is or are broken, for example, by folding of a pressed workpiece. An electronic control system including a central processing unit to implement the above-described method and system is also disclosed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.