Abstract: The apparatus detects the fact that a predetermined temperature threshold, in particular a low temperature threshold, has been crossed, and prevents any subsequent use of the appliance. The apparatus includes a reversible thermostatic switch capable of changing from a first stable state to a second stable state, and of delivering an alarm signal when it finds itself in the second state; and control means co-operating with the switch to respond to the alarm signal by delivering a disable signal for disabling the electronic appliance. According to the invention, the apparatus further includes a DC voltage source (15), an electrical or electronic component (17) capable of taking two states corresponding to said first and second stable states connected in a loop with the voltage source and the switch so that a current passing through the thermostatic switch causes a change from the first state to the second state.

Abstract: A data-recording machine is protected against temperature overshoots by a device (12) for protecting electrical lines comprising two blister-type thermosensitive elements (10C, 10F) which control series-connected electric contacts (7C, 7F) so as to close the electrical line outside the normal operating range and to prohibit operation even after a return to said range.

Abstract: An electric switch, particularly a thermostatic switch, includes a pair of switches having contacts connected to three terminal members having connector terminals aligned along a common axis. The connector terminals include a pair of outside connector terminals and a central connector terminal. One switch has a fixed contact connected with one of the pair of outside connector terminals and a movable contact connected with the central connector terminal. The other switch has a movable contact connected with the other outside terminal and a fixed contact connected with the central connector terminal.

Abstract: A thermally-sensitive electrical control is mounted to the head of an electric immersion heater of an electric kettle or like container. The control has an outer periphery of less radial extent than the head so as to be passable, during assembly, through an opening in the wall of the associated container such that the head may be positioned in the opening with the control mounted thereto by insertion of the control through the opening from inside the container. The control includes an electric switch and a snap-action, overheat sensing bimetallic actuator disposed on the side of a body portion of the control which faces the head when the control is mounted thereto and a snap-action steam responsive bimetallic actuator mounted to the opposite side of the body portion. The switch is operated by the bimetallic actuators through an over-center mechanism disposed on the opposite side of the body portion and connected to the switch by a U-shaped link slidbly mounted in the body portion.

Abstract: An electric immersion heating element dry switch-on or boil dry protector unit for an electrically heated water boiling vessel comprises primary and secondary bimetals (31,32) responsive to the heating element head temperature and each arranged for actuating a respective one of primary and secondary switching contacts (11,12) connected in the line and neutral sides of the heating element supply via respective push rods (38,44). The secondary bimetal (32) is arranged to break later than the primary bimetal (31) in a dry switch-on or boil dry situation giving rise to excessive element temperatures, and to reset before the primary in a reducing temperature situation. The secondary bimetal (32) and associated switch contacts (12) provide back-up protection in the event of failure of the primary protection on account for example of welding of the primary switch contacts (11).

Abstract: A thermally-responsive electric switch has a manually-releasable latching arrangement which makes use of a latching member (6) comprising an L-shaped or bellcrank lever having an integrally formed part (11) which constitutes a release member and connects to the end of one limb (9) of the L-shaped lever via a resilient hinge portion (12). The end of the other limb (8) of the L-shaped lever constitutes a latching abutment (10) for engagement with a member (3) of the switch. The latching member (6) is so arranged that, when the switch operates, the latching abutment (10) engages with the respective member (3) of the switch so as to preclude its return and thereby latch out the switch. Resetting is achieved by depression of the release member part (11) of the latching member (6), this causing the L-shaped lever to pivot generally about the junction of its two limbs such that the latching abutment (10) moves out of its latching position and permits the switch to reset.

Abstract: A thermal switch comprising a plurality of outer terminals respectively having a fixed contact, a movable contact spring divided into a plurality of mutually parallel contact spring parts each having a movable contact for contacting with and separating from the fixed contact and a plurality of bimetals respectively operating at differently set temperatures and provided so as to independently actuate the respective contact spring parts, whereby resetting-type contacts are reliably opened and closed in response to fluctuations in the atmospheric temperature through one of the bimetals which has a relatively lower first set-temperature and, when the particular bimetal of the relatively lower first set-temperature fails to operate and the atmospheric temperature further rises, non-resetting-type contacts are reliably opened through the other bimetal having a relatively higher second set-temperature.

Abstract: A temperature switch includes a housing, a movable contact mounted in the housing for movement between a first and second position, a fixed contact mounted in the housing and operatively associated with the movable contact for engagement with the movable contact in the second position, a heat sensitive plate mounted in the housing and which constitutes an amorphous metal member with a highly expansible metal wherein the amorphous metal member is exposed to a predetermined region, the temperature of which is to be determined wherein deflection of the heat sensitive plate is caused by a temperature change in the region for movement of the movable contact with respect to the fixed contact.

Abstract: A temperature responsive switch is provided which comprises a pair of bimetal discs having different temperature-deformation characteristics, a pair of fixed electrical contacts and a movable electrical contact. The movable contact engages one of the fixed contacts in response to a deformation of the pair of bimetal discs or remain free from engagement with either fixed contact. The engagement of the movable contact with one or the other of the fixed contacts and the absence of its engagement with either fixed contact constitute three conditionswhich permits a detection of a temperature of at least three different regions.

Abstract: The present invention relates to an improvement in bimetallic thermostatic switches having several temperatures of response.

Abstract: An electric temperature protection switch is provided which has at least two encapsulated contacts in a housing and a current transmission member controlled by a temperature sensing bimetal snap plate. A manual push button device, biased by the force of a reset spring is provided for switching the released switch on again. The switch includes a first bistable snap element directly connected with the transmission member for holding the same in the respective on and off positions. A switch plunger is disposed at a distance from the current transmission member corresponding maximally to the switching stroke of the push button and guided slidably on the switch housing. A second snap element cooperates with the switch plunger and the push button device, which second snap element is moved into a passive position from an active position as the result of actuation of the manual device at critical temperatures, whereby switching of the transmission member from the off to the on position takes place.

Abstract: A thermostat assembly which includes therein two sets of thermostats connected in series with each other.

Abstract: A motor protector for use in motors having a high operating temperature employs a snap-acting composite thermostat element to actuate the protector wherein the multilayer thermostatic material embodied in the element has an electrical resistivity value from 20 ohms/c.m.f. to 400 ohms/c.m.f. and a flexivity value from 90 .times. 10.sup.-.sup.7 inches per inch per degree Fahrenheit to 110 .times. 10.sup.-.sup.7 inches per inch per degree Fahrenheit to provide for better calibration, longer life, and better space control in the protector for use in motors having higher operating temperatures.

Abstract: A multiple bimetallic snap disc thermostat is disclosed in which two series connected switch mechanisms are respectively operated by two concentric bimetal snap discs having the same diameter. One snap disc is thermally automatic in operation to open and close its associated switch upon reaching its calibration temperatures. The outer disc is a one-shot disc which does not automatically reset and cannot be manually reset after operation. The two discs are mounted in a single, disc retaining cup, and are spaced by a ring positioned between their peripheries. This allows said discs to be formed of the same size and provides easy mounting. A single fixed contact member provides the fixed contact for both switches. The contacts of the switch associated with the automatic disc are capable of repeated operation whereas the contacts of the switch associated with the one-shot disc are not structured for repeated cycling.