US 7,075,040 B2 · Stirring hot plate

Abstract

A stirring hot plate for simultaneously heating and stirring a mixture includes a phase controlled motor that spins magnets which couple to, and thereby spin, a stir bar within the mixture. In addition to spinning the magnets, the motor includes an operational mode in which the motor is rapidly braked thereby quickly spinning down the stir bar. The stirring hot plate also includes a visual indicator to the user that the platform is hot-to-the-touch that is especially effective when the stirring hot plate is not in use.

Claims22

Dependent claims

A stirring hot plate for supporting a vessel holding a substance to be heated and/or stirred, the stirring hot plate comprising:

a plate having a generally horizontal upper surface adapted to support a vessel containing a substance to be heated and stirred;
an electrical heating element in a heat transfer relation with the plate;
a motor mounted below the plate and adapted to provide a magnetic field coupling with a magnetic stir bar placed in the vessel, thereby causing the stir bar to stir the substance and
a control electrically connected to the motor and the heating element;
and
a control panel electrically connected to the control and comprising
multiple visual displays operable by the control to provide two independent visual indicators that the plate is hot-to-the-touch in response to a temperature of the plate being greater than a first temperature value, and the multiple visual displays comprising
a hot plate graphic indicator, and
a multi-character display.

6 more elements

Dependencies are inferred from the claim text.

Stirring hot plate

Life of this patent

Stirring hot plate

Life of this patent

Abstract

Claims22