Safety device for a kneading machine using rolls
US5921367A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 25, 1997 |
| Grant date | Jul 13, 1999 |
| Priority date | — |
| Expiry date | Feb 25, 2017 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF16P3/147
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
A safety device detects when a worker's hand enters a hazardous region between rollers of a kneading machine, and stops rotation of the rolls to prevent an accident. Each time the rollers are stopped, the orientation of photoelectric sensors is switched from the vicinity of the gap between the two rollers to a test reflection member, and the quantity of received light is compared to a predetermined value, to prevent workers form starting work without knowing a fault or accident has happened. More specifically, a bar electrode of an electrostatic capacitance sensor is disposed above and near the gap between the two rollers, for detecting a physical quantity that is changed by entry of a worker's hand. When the electrostatic capacitance detected by the sensor exceeds a predetermined value, a judging circuit supplies a control signal to stop a driving unit that operates the kneading machine. Heat ray sensors or photoelectric sensors may be used as alternatives to electrostatic sensors. As an additional feature, case housing light projectors and photoelectric sensors are rotatably disposed above and near the gap between the two rollers, and a test reflector is disposed on the side of t…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.