Abstract: An electric clothes iron with circuitry for automatically disabling power to the iron when the iron is left unattended for a certain period of time. The circuitry includes a circuit for controlling two timing periods, one for controlling the shut off when the iron is in the horizontal position, and one for controlling the shut off when the iron is in the vertical position. When the user grasps the handle of the iron, the timing circuits are disabled. However, once the user removes his hand from the iron, one of the two timer periods starts to expire. If the timer reaches its prescribed limit before the handle is again grasped, the iron will automatically shut off. If the user grasps the iron during the timing process, the timer will be disabled, and will start the counting from zero the next time the hand is removed from the handled.

Abstract: An overtemperature protection assembly with a mount, a solder terminal and a bridging connector. The mount is a block of ceramic material with a slot extending therethrough. The solder terminal has an end that is located in the slot and forms a frictional connection therein. The bridging connector has a busing terminal and a spring contact. The busing terminal has an end that is located in the slot. The spring contact has a first end connected to the busing terminal and a second end that is deflected towards the solder terminal and soldered thereto. If the solder connecting the second end of the spring contact to the solder terminal melts from excessive heat, the spring contact deflects away from the solder terminal thereby breaking electrical connection between the solder terminal and the busing terminal.

Abstract: An electrothermal color-varying instrument for inducing color change in a color-varying layer includes a heat generating element composed of a sintered barium titanate thermistor in face-to face contact with a heat transmitting member having a heating end portion for transmitting heat to the thermal color-varying layer. The thermistor has:(i) a positive temperature coefficient on the electrical resistance within a temperature range from 25.degree. C. to 70.degree. C.;(ii) a volume resistivity at 25.degree. C. (.rho..sub.25) within a range of 9.8.times.10.sup.-3 to 2.97.times.10.sup.5 .OMEGA..multidot.cm; and(iii) a ratio (.rho..sub.70 /.rho..sub.25) of the volume resistivity at 70.degree. C. to that at 25.degree. C. within a range of 5.ltoreq.(.rho..sub.70 /.rho..sub.25).ltoreq.400.The electrothermal heat generating element generates heat under the application of a voltage in the range of 0.8 to 40 volts and maintains a saturated heating temperature within a range of 30 to 100 degrees C.

Abstract: Thermostatic control of an electric iron is achieved through utilizing the expansion and contraction of the iron's sole plate relative to a low expansion reference member. In one embodiment, a flexible reference member extends from a fixed mounting at the tip of the sole plate to a switch unit at the rear of the sole plate. The reference number is connected to, and held in tension by, a snap acting actuator within the switch unit, such that as the sole plate expands, the free end of a blade is pulled by the reference member to cause a contact carrying tongue to snap away from a contact to interrupt the power supply. In addition, the temperature of operation may be controlled by varying the effective length of the reference member such as, for example, by deflecting it laterally by a cam member.

Abstract: A thermally responsive control especially for a clothes iron combines an adjustable, temperature-regulating thermostat and an over-temperature control for limiting maximum temperature levels on a plastic mounting bracket where the over-temperature control also protects the mounting bracket against damage from overheating.

Abstract: An electric steam iron housing has a sole plate with a generally flat upper surface having affixed thereto a one-piece heating assembly having a front portion and a rear portion. The front portion contains a serpentine steam generating passage with an inlet communicating with a water supply container on the housing and steam outlet leading to steam vent openings extending through the sole plate. The rear portion includes top and sidewalls defining a downwardly open chamber in which is disposed a multilayer PTC electric heating element assembly in surface-to-surface contact with the upper surface of the sole plate for heating the sole plate and the steam generating passage. An adjustable thermostat responsive to the temperature of the sole plate is connected in series with the heating element. The handle of the iron is detachable and designed to serve as a storage case for the iron and the iron can be placed in the case only when the thermostat adjustment knob is in the "Off" position.

Abstract: A soldering iron bit is heated by an electrical heating element including a resistive element consisting of granular boron carbide packed in a quartz tube embedded in a piece of copper. A first power lead is electrically connected to the boron carbide at one end of the quartz tube. This first power lead passes through and is electrically insulated from the piece of copper. The second power lead is electrically connected to the boron carbide at the other end of the quartz tube, either directly or via the piece of copper. In use, connection of the first and second leads to an electrical power source causes the resistive element to generate heat in a very fast manner and to transmit this heat to the piece of copper. The piece of copper may be connected to or constitute the soldering bit and can be provided with a built-in thermostat comprising a meltable salt inserted in a hole provided in the piece of copper.

Abstract: A thermostatically controlled electric flatiron having a heater circuit of sufficient wattage to achieve abnormally high soleplate temperatures on continuous operation is provided with an overtemperature protection assembly for opening the heater circuit before damaging high soleplate temperature occurs on thermostat failure. The assembly includes first and second members connected in the heater circuit and electrically isolated from the soleplate and each other bridged by a third spring-biased circuit member to complete the heater circuit. A slug of eutectic alloy forms a fusible joint bonding the third member intermediate its ends to one of the first and second members to hold the third member against the spring bias in circuit completing contact with the first and second.

Abstract: A fuse is disclosed for protecting thick film devices. The fuse comprises two blocks of material mounted to the substrate that carries the thick film device. The blocks are mounted in close proximity to one another, in axial alignment, but in a spaced apart relationship. An electrically conductive fusible link (e.g. solder) straddles the two blocks so as to complete an electric circuit.

Abstract: Electrical resistance heating element including a number of metal strips arranged in a meander-like pattern. In the resistance metal strips, which are made from a non-expensive base sheet material like lead, there is incorporated at least one fuse which will operate if the heat transfer from a randomly placed area of critical size (a critical area) is substantially blocked. The fuse or fuses are preferably constituted by a lead/tin alloy rolled into intimate contact with the lead base material.

Abstract: An electrically heated appliance, such as a steam iron, is provided with an adjustable stacked thermostat assembly having an integrated overtemperature protection control. In the case of a steam iron, the thermostat assembly is mounted on a boss on the soleplate and includes a pair of contacts carried by spring contact blades and adapted to be actuated by a heat deformable bimetallic blade to make and break the circuit to the electric heating element of the iron. The overtemperature protection control includes an electrically conductive rivet electrically connected to one of the electrical power supply terminals of the iron and a U-shaped electrically conductive spring having a first end electrically connected to a conductive member in circuit with one of the spring contact blades and a second end soldered to the rivet by a solder joint fusible at a selected overtemperature to melt and break the circuit between the rivet and the spring.

Abstract: An adjustable stacked thermostat assembly, particularly for use in an electric appliance, such as an electric steam iron, includes a lower bimetallic heat deformable blade, an intermediate stiff conductive spring blade carrying a electrical contact and connected to a first electric terminal and an upper less stiff conductive spring blade carrying a cooperating contact and connected to a second terminal, with all of the blades being supported, secured and spaced apart at one end by interposed insulators. In operation movement of the deformable blade is transmitted to the upper blade to make and break the contacts to control heat to the appliance controlled by the thermostat.

Abstract: An overtemperature protector for an appliance having an electrical heating element includes a fixed contact, a movable contact carried by a spring blade and settable into engagement with the fixed contact to complete the energizing circuit to the heating element by stressing the spring blade, and a torsion spring having an arm engageable with the spring blade to hold the contacts in engagement against the stress bias of the spring blade. A fusible pin retains the arm of the torsion spring in engagement with the spring blade, thus locking the contacts closed. Excessive heat in the appliance causes the pin to soften, thereby allowing the torsion spring to shear the pin and release the movable contact to open the heating element energizing circuit.

Abstract: An overtemperature protector for an appliance having an electrical heating element, the overtemperature protector being formed basically of just a spring blade positionable to bring a contact on the surface of the blade into circuit-energizing engagement with a fixed contact, and an insulator-capped fusible pin retaining the blade in that position. Excessive heat in the appliance softens the pin, allowing the spring blade force on the insulator cap to shear the pin and interrupt the circuit. The overtemperature protector is preferably incorporated in a thermostatic control, the fixed contact being supported on a lateral extension projecting from one circuit element of the thermostat assembly and the spring blade being supported within the assembly with an insulating spacer separating it from the thermostat element having the lateral extension. The spring blade is preferably sickle-shaped for compactness despite having a long length for low force to minimize effects of creep of the fusible pin.

Abstract: An electric heating appliance such as a coffeemaker, has a metallic base with an upper exposed surface and an electric heater on its lower side for heating the surface by conduction. A thermostat comprising a plastic-walled packaged unit with an opening through which an internal bimetal sensor is exposed is provided for controlling the heater and is mounted in a depressed niche formed in the surface of the heater. A detachable U-shaped metallic cover covers the opening and includes a heat-conducting projection extending through the opening very closely adjacent the sensor. The thermostat is positioned so that the cover faces and abuts the surface of the niche and a flexible clamp secures the thermostat in the niche and biases the projection and sensor closely together for fast thermostat response. The base may be an aluminum casting with the heater comprising a cast-in circular sheathed electric heating element.

Abstract: In an electric flatiron with a soleplate and central upstanding boss and having a handle having a temperature adjusting lever in the front of the handle, an improvement is provided in the temperature regulating assembly that comprises a snap action thermostat which is supported on the boss with a substantially vertically movable adjusting screw to vary the thermostat settings. An insulated cap is provided on the top of the screw and the cap has an outer splined surface. A rod is connected at one end to the temperature adjusting lever forward of the screw for rotation by lever movement for setting temperature. The rod has an offset portion at its other end loosely fitting in a driving engagement over the splined surface so the offset slides vertically over the splined surface forming a universal-like connection as the rod is rotated by the lever to turn the screw and vary the thermostat setting of the iron without undue backlash.