Temperature sensor and heating device for hot runner systems
US6897418B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | Jul 15, 2003 |
| Grant date | May 24, 2005 |
| Priority date | — |
| Expiry date | Nov 10, 2023 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB29C2045/2746
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
A temperature sensor for use in hot runner systems includes a resistive element which is connectable via contacting means to a control circuit for a heating device and which includes at least one element portion of larger electrical resistance than its remaining portions, preferably larger by a factor of 2 to 100. The resistive element portions may form U-shaped bows or loops or may be meandering. Two resistive tracks above one another are separated by insulating layers, e.g. ceramic dielectric layers. The resistive element portions may consist of different materials. In connection with a heating device, the temperature sensor is located on or in the body of a manifold or a nozzle, with meandering and/or bifilar heating conductors whose electrical resistance in the middle is smaller than in the top and bottom regions. The temperature sensor portion is tightly enclosed in a zone of high resistance by adjacent heating conductors. A dielectric layer may be undetachably fixed to the manifold or nozzle body and after firing, be under compressive pretension relative to the body.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.