Heater and thermostat unit
US4975562A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Apr 6, 1989 |
| Grant date | Dec 4, 1990 |
| Priority date | — |
| Expiry date | Apr 6, 2009 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01H37/26
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A heater for heating water in an aquarium tank is provided with a thermostat which includes a bimetal strip carrying one contact and another strip carrying another contact. Upon deformation of the bimetal strip in response to temperature changes, the contacts are closed to connect the heater with an electrical supply circuit. The distance between the contacts is initially set by a rotatable cam acting on a curved portion of the bimetal strip. A cylindrical body which supports the cam to rotate the latter is provided with a helical groove in which is engaged an indicator captured in an elongated axial slot formed in a support of the cylindrical body. The support has at least one scale on its surface visible through a glass container of the heater. When the cam is rotated to change the distance between the contacts this change is indicated by the position of the indicator on the scale.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.