Tie bar monitoring system
US5161594A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 21, 1988 |
| Grant date | Nov 10, 1992 |
| Priority date | — |
| Expiry date | Dec 21, 2008 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB22D17/32
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
A system is presented for monitoring, measuring and controlling tie bars in, for example, a die casting machine. In this system, an ultrasonic device is used to monitor stress, strain, load, bending and temperature changes in each of the tie bars (typically four). This ultrasonic system will sound an alarm and/or shut down the die cast machine if bending in individual tie bars exceeds a predetermined limit, or if the variance in the combined tie bar loads exceeds a predetermined critical limit. The system of the present invention is comprised of an ultrasonic device that monitors changes in tie bar length with applied load, transducers that send and receive the ultrasonic signals to and from the tie bars, a microprocessor to select the proper transducer and log the data, and a multiplexer that switches the transducer signals on command from the controlling microprocesor. Preferably, the tie bars are instrumented with four equally spaced transducers. Also in a preferred embodiment, the four equally spaced transducers are positioned such that one transducer is in each quadrant and each transducer is mounted on the radius of the tie bar, between the center and the outer edge.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.