Abstract: A firestat for providing an output for controlling an opening and closing of a fire/smoke damper. The firestat includes a fire/smoke damper test switch and an actuator configured to depress the fire/smoke damper test switch. The firestat is further configured to release the fire/smoke damper test switch in response to a depressing force applied to the actuator, wherein melting or other damage to the actuator causes a release of the test switch.

Abstract: The invention relates to a thermo-pneumatic actuator having a cavity defined by walls and being hermetically sealed, which is inflated with a working medium that alters the gas pressure thereof when a temperature change occurs. A wall region of the cavity is constructed as a ductile membrane, which can be deflected in at least two working positions located on both sides of a neutral position, in which the membrane is curved in opposite directions to one another. In order to alter the gas pressure in the cavity, and to adjust the membrane from one working position to the other working position, a tempering device is heat-conductively connected to the working medium. In the neutral position, the membrane is compressively loaded such that respectively, it maintains its position in both working positions if no outside force impacts the membrane.

Abstract: A nail feeding mechanism is provided with a front feed claw (9) and a rear feed claw (10). The rear feed claw (10) is provided with a contact portion (10b) on a front side of a claw portion (10a) . A face of the contact portion (10b) to be brought into contact with connected nails is wider than a gap between nails in a width thereof and cannot enter between nails. When the front feed claw (9) is moved rearward and catches a final nail (TN1) of a first row, the contact portion (10b) and the claw portion (10a) move into a nail path, the contact portion (10b) enters between the final nail (TN1) of the first row and a front nail (FN2) of a second row and the claw portion (10a) enters a rear side of the front nail (FN2) of the second row.

Abstract: An electronic device integrally formed with an automatic switching-off structure for protecting the device from overheating. At least one conducting lead of the electronic device is mechanically and electrically connected to its corresponding electrode by means of a solder column having desired melting point, with an appropriate spacing being kept between the conducting lead and the electrode. The coating layer of the electronic device is formed by a material such as epoxy resin which will soften and release a gaseous substance when heated to a temperature near its ignition point. When the temperature of the device exceeds the melting point of the solder, the solder column melts to break the electrical circuit and prevent overheating of the device. If the electronic device per se has higher working temperature, the coating layer is formed by a material having a higher ignition point such as silicon resin or silicon rubber which will not soften and expand when heated to a temperature near its ignition point.

Abstract: An electric relay has a casing enclosing a thermally expandable mass associated with a thermistor (PTC) as a heat source, connected to an electric excitation circuit. A rod projects from said casing to come in contact with a rocker lever which, in conjunction with the reaction of a spring, causes a second spring to bend. The bending second spring moves an armature comprising a contact point, so that the contact point comes in contact with a second fixed contact point, thus closing an electric circuit. The elastic reaction of the springs and a tooth on the rocker lever bring the relay back to the resting position when power to the thermistor is interrupted.

Abstract: A heater for heating liquids such as water in an aquarium comprises a water-impermeable housing including a heating section for immersion in the water. Within the heating section of the housing is a flexible, distributed planar heating element. The housing is resistant to breakage from mechanical and operating abuse and has a high heat transfer coefficient and high heat distortion temperature. To prevent the housing from melting when a control element of the heater malfunctions, preferably the aquarium heater includes temperature limiting means such as a circuit protection element comprising a material having a positive temperature coefficient of resistance. Preferably, the heating section of the housing is fabricated with large surface area walls to accommodate the planar heating element, and is provided with coupling means for maintaining the heating element thermally coupled to the walls of the heating section.

Abstract: A heater for heating liquids such as water in an aquarium comprises a water-impermeable housing including a heating section for immersion in the water. Within the heating section of the housing is a flexible, distributed planar heating element. The housing is resistant to breakage from mechanical and operating abuse and has a high heat transfer coefficient and high heat distortion temperature. To prevent the housing from melting when a control element of the heater malfunctions, preferably the aquarium heater includes temperature limiting means such as a circuit protection element comprising a material having a positive temperature coefficient of resistance. Preferably, the heating section of the housing is fabricated with large surface area walls to accommodate the planar heating element, and is provided with coupling means for maintaining the heating element thermally coupled to the walls of the heating section.

Abstract: A device for filling a pneumatic tire and sensing the air pressure therein has a check valve disposed within a valve stem and a pressure sensing switch which is temperature compensated to adjust for air pressure changes within the tire due to changes in ambient temperature. Substantially perfect compensation can be achieved, within a limited range of operation, whereby the set point pressure versus temperature characteristic will track with the related tire pressure versus temperature characteristic. A manual set point adjustment feature is provided whereby the switch can be calibrated after it is assembled within a wheel and pneumatic tire. The switch can also be employed independently of, as well as in conjunction with, the check valve.

Abstract: A thermostatically controlled safety heater for upright immersion in an aquarium includes a housing with an axially extending, heat-transmitting tube forming a chamber in which an electric heating element is disposed in radially spaced relation from the tube. The radial space between the tube and element, over substantially the axial length of the element, is filled with a heat conducting, thermally expansible liquid. An actuator device including a linearly movable plunger reactive to thermal expansion of the liquid is provided for opening and closing a switch in circuit with the heating element for maintaining the heater at a desired temperature. A hunting tendency of the switch contacts is overcome by providing a damping medium in the form of an air space having a volume less than about ten per cent of the volume of liquid between the plunger and the liquid. An expansible sealing diaphragm supports the plunger and isolates the liquid to the portion of the tube in which the heating element is disposed.