This invention relates to electrically operated mixers and, in particular, to such mixers having a power boost circuit which can be electrically energized to increase the power of the mixer.
Hand-held electrically operated mixers are one of the primary devices used by persons in cooking and baking foods. Some high performance mixers have power boost circuitry to selectively increase the torsional power of the mixer when the user is mixing particularly heavy food products. Generally speaking, the mixers of the foregoing type have a primary operating switch which is used to connect the mixer to a source of electrical energy and to change the speed of the mixer as desired by the user. The mixer will also include a secondary switch for selectively increasing the torsional power of the mixer.
Since both the primary and secondary switches connect various electrical circuitry of the mixer to the source of electrical power, it is desirable that the secondary switch not be independently capable of electrically actuating the mixer. That is to say, the primary switch should be the sole means for initially energizing the mixer while the secondary switch should only be actuated when the primary switch has already connected the mixer to the source of electrical power.
Accordingly, it is an object of this invention to prevent the secondary switch from connecting the mixer to a source of electrical energy in the absence of the primary switch being initially placed into an operating position for connecting the mixer to the source of electrical energy.