Appliance for monitoring and safeguarding stirring operations, especially in chemical laboratories

The invention relates to an appliance, consisting of a probe and a monitoring unit, for monitoring and safeguarding stirring operations, which responds to a magnet rotating during the stirring operation and indicates by means of signals a failure of the stirrer or a reduced or irregular stirring action, or optionally, by switching off the heating current supply, averts the risk of the stirred material being overheated. According to the invention this is achieved by a probe (S in Figure 1) registering, by means of magnetic force transmission, the proper rotation of the stirrer bar or the stirrer shaft. According to the invention, the probe S has reed switches (S1, S2) arranged therein, whose moving metal parts having an electric switching function are set into back-and-forth movement by the magnet revolving in the stirred material. The invention can be used in all those cases, preferably in chemical and related laboratories, where it is absolutely necessary to maintain a stirring operation over prolonged periods, in order to prevent risk due to overheating, charring, delayed boiling.