Abstract: A temperature controller for use with a fryer of the type comprising a vat containing cooking oil and heater, such as a gas burner or electrical heating element, for heating cooking oil comprises a temperature probe for sensing the temperature of the cooking oil, a temperature selector switch producing a signal corresponding to the selected temperature for the cooking oil and also producing a signal corresponding to a normal temperature approximately 25.degree. below the selected temperature. A heat demand comparator produces a heat demand signal when the temperature of the cooking oil is below the selected temperature. A normal temperature comparator compares the temperature of the cooking oil with the normal temperature and provides a signal when the cooking oil is in the normal temperature range, and a cooking gate inhibits this signal if cooking is taking place in the fryer. A heating element control oscillator provides pulses.

Abstract: A control circuit for electrically heatable windshields of automotive vehicles which controls the quantity of heat supplied by the vehicle alternator to the windshield heating element to be adequate for deicing the windshield yet limited to avoid windshield damage and to minimize decoupling time of the alternator from the vehicle battery. The control circuit, which employs an inexpensively installed temperature sensor element that senses ambient temperature, responds to the temperature difference between the ambient and a reference deicing temperature and to the supplied heating power for controlling the duration of the heating period.

Abstract: A system comprising a heat generating load such as a heater, a power control element for directly or indirectly supplying current to the heat generating load, a temperature detecting circuit for producing an ON signal when the temperature of the heat generating load is lower than a set temperature and an OFF signal when the temperature is higher than the setting, and a control circuit for feeding an ON or OFF signal to the power control element in response to the ON or OFF signal from the temperature detecting circuit. The control circuit includes a failure detecting circuit for logically comparing the signal from the temperature detecting circuit with the terminal voltage across the power control element to produce output when the power control element is in conduction although the signal from the temperature detecting circuit is an OFF signal.

Abstract: A plasma torch includes an annular cathode having an annular peripheral edge from which an arc is discharged. A pair of annular nozzle elements are coaxially disposed on the opposite sides of the cathode. Each nozzle element has an annular edge hanging over the annular peripheral edge of the cathode, and the annular edges of the nozzle elements define therebetween an annular outlet opening for the torch. Gas is introduced between the cathode and the nozzle elements and emitted through the annular outlet opening in a plasma jet. A magnetic field is developed across the annular outlet opening to cause the plasma jet to rotate along the annular peripheral edge of the cathode for its uniform emission from the entire perimeter of the annular outlet opening.

Abstract: A temperature control system for electric surface heater of piled layers of a heating element across which a commercial AC source current is fed and a thermosensitive electrode opposing the element through thermosensitive element showing negative impedance characteristics with temperature rise. In the system, an AC signal voltage different from the source current is applied between the heating element and the thermosensitive electrode, and excessive variations in the signal voltage responsive to the negative impedance of the thermosensitive element is detected to disconnect or connect the heating element and the source.

Abstract: In the method and apparatus disclosed herein, heat processing pulsing current is passed, on command, through the conductive backing of an exposed record sheet of heat-processable photosensitive material. The sheet resistance is included as one arm of a bridge which contains a settable comparison resistance in another arm. The cold sheet resistance is sensed and is used by a sample and hold arrangement to set the comparison resistance to a corresponding comparison value which represents the cold sheet resistance multiplied by a preselected percentage. That percentage is one which is known to correspond to the desired processing temperature to which the sheet temperature is to be raised in order to effect the processing of the sheet.

Abstract: A control circuit for supplying power to the heater of an electrically heatable windshield of an automotive vehicle while simultaneously providing the requisite current for the standard electrical system of the vehicle includes a resistive heating element connected in series between the vehicle alternator output and the high voltage terminal of the vehicle battery, so that current conducted through the heating element is supplied to both the battery and the load circuit. A control circuit, responsive to the alternator output voltage and the battery voltage, controls a voltage regulator to regulate the alternator output voltage within a first narrow band corresponding to the rated battery voltage and within a second narrow band corresponding to a given power rating for the heater.

Abstract: Precise concentric alignment of the coolant, plasma and sample gas tubes d in conventional ICPs is an operationally important factor often achieved by fused arrangements which effectively preclude dismountability for maintenance and repair. Spacer rings slip-fitted into the coolant and plasma passages provide support for the concentric arrangement and also permit dismountability. Each ring is slotted to direct coolant and plasma gases and improve their intended functions. One ring spans the plasma tube and has a number of vertically-directed peripheral slots producing a laminar plasma gas flow. The other ring spans the coolant passage and has a pair of threads cut at spaced intervals to spiral the coolant gas and improve its heat transfer function. A separable base member supports the concentric lower ends of the tubes.

Abstract: Disclosed herein is a method and a digital electronic steam humidifier control for use with a humidifier system including an electrode boiler to provide a normally repetitive fill, boil, fill-on-drain cycle. The humidifier control includes circuitry for providing an analog signal proportional to the electrode current, and a comparator network which receives the analog signal and a reference voltage and scaled voltages provided by additional circuitry to establish predetermined levels of electrode current at which the control responds.

Abstract: The materials to be chem-milled are coated with a maskant material, a template having a specific hole pattern is then placed over the masked surface of the material. A laser beam is then directed towards the template and is scanned either manually or by numerical control means along the hole pattern. The laser is maintained at each hole for a sufficient length of time to enable the maskant to be burned from the material. The material is then chem-milled by any conventional means thereby forming holes through the material at the maskant free areas. The remaining maskant is then removed from the surface of the material.

Abstract: Disclosed herein is an improvement of a welding process for welding a steel pipe, wherein a gas metal arc welding is performed to form the first welding layer and a submerged arc welding is performed to form the last welding layer. According to the conventional gas metal arc welding process, i.e. the MIG or CO.sub.2 welding processes, the combined use of a high welding current and a welding wire having a small diameter is known to bring about the rotation of the welding arc and the formation of an undercut along the toe of the weld metal. The purpose of the present invention is to weld a steel pipe having either a large thickness or an excellent ductility at a temperature of less than -40.degree. C., or both. According to the present invention, the combined use of a high welding current and a wire having a small diameter is possible, by employing a gas mixture containing an inert gas as a major part thereof and CO.sub.2 as an additional part thereof as a shielding gas.

Abstract: A control circuit is disclosed suitable for use with a toaster or other food browning device which utilizes a radiant energy source to brown food. A light sensitive variable resistor, or photocell, is optically coupled to light reflected from the food being browned in the device. A voltage generated by a voltage divider including the light sensitive resistor therein is compared with a preselectable voltage generated by a second voltage divider to determine whether the heat source should be turned on or off. Suitable solid state control circuitry is provided to ensure that a start-up delay is provided at the beginning of each browning cycle and to reset the circuit for future operation when the desired browning of the food is achieved.

Abstract: In electron beam apparatus having a souce of electrons and a target area toward which the electrons are directed, electron beam forming means are provided along the path from the source to the target. These forming means include a first beam shaping member having a first spot shaping aperture therein, a second beam shaping member having a second spot shaping aperture therein, and means focusing the image of the first aperture in the plane of the second aperture to thereby form a composite spot shape defined by the image of the first aperture and the second aperture. Further means are provided for focusing the image of the composite spot in the target area.Preferably, the apertures are square shaped. Thus, by varying the position of the superimposed image of the first aperture with respect to the second aperture, a wide variety of rectangular shaped composite spots with different dimensions is obtainable. This permits the exposure of rectilinear patterns, e.g.

Abstract: In the body of a plasma arc torch head coolant inlet ducts extend normally to the portions of the nozzle surface subject to maximum heating. The rate of cooling and a permissible power of the plasma arc torch are markedly increased by directing the flow of incoming coolant directly against the surface being cooled. Where the nozzle lateral surface is exposed to the effect of a plasma-forming arc, the coolant inlet ducts are arranged so as to open radially into said lateral surfaces. If electromagnetic coils are provided to allow control over the plasma jet, a coolant is supplied to effect intensive cooling of the nozzle end face.

Abstract: One or more pairs of vertically-spaced-apart sidewardly-aimable plasma arc cutting torches, the upper one angled upward and the bottom one downward, on the end of a horizontal boom movable longitudinally fore and aft and angularly sideward, are used to double-cut the tube bundle of a steam generator progressively in a manner clearing a path that accommodates torch assembly advancement.

Abstract: Temperature responsive power supply apparatus for electrical resistance heating, e.g. for weld stress relief, has a power supply transformer comprising first and second secondary windings in series with one another and first, second and third conductors for connecting the secondary windings to heating elements. A pair of temperature sensors provide temperature signals corresponding to the temperatures of heated zones heated by the apparatus, and a pair of control units responsive to the temperature signals control the current flow through the conductors. A switch enables one or both control units to regulate saturable reactors or the like in series with the conductors, whereby the control unit can regulate two respective heating circuits each including one of the secondary windings or one of the control units can regulate a heating circuit including one or both of the secondary windings. The apparatus provided improved versatility for heating one or more large or small pipe welds.

Abstract: In a temperature control having a heating element and a temperature sensor for sensing the temperature of an object being heated by the heating element and providing signals effective to control electric energy to be supplied to the heating element, there is provided compensator means for compensating for a variation in the temperature of the object which may be caused by heat resistance and other factors while transmitting heat from the heating element to the object. The temperature of the object is equivalent to a desired one without any influences of the heat resistance. In one preferred form, an operational amplifier having two input terminals is provided one connected to the temperature sensor such as a thermistor and the other connected to a reference potential representative of the desired temperature. An output terminal of the operational amplifier is connected to the heating element.

Abstract: Plasma-MIG welding in which a thermally ionizable gas stream is flowed through a nozzle non-consumable electrode having a central orifice and a surrounding annular opening toward a workpiece and is thereby split into a central gas column enveloped by an annular gas shield. A consumable electrode is fed through the central gas column toward the workpiece, with the establishment of a MIG-arc therebetween. A plasma arc is then spontaneously established by means of the MIG-arc between the nozzle non-consumable electrode and the workpiece. The central plasma gas column is accelerated by constriction of the annular gas shield downstream of the nozzle non-consumable electrode.

Abstract: Plasma-MIG welding in which a thermally ionizable inert gas stream is flowed through a nozzle non-consumable electrode having a central aperture and a surrounding annular aperture toward a workpiece and is thereby split into a central gas column enveloped by an annular gas shield. A consumable electrode is fed through the central gas column toward the workpiece, with the establishment of a MIG-arc therebetween. A plasma arc is spontaneously established by means of the MIG-arc between the nozzle non-consumable electrode and the workpiece.

Abstract: A control system having a thermostatically operated control device for operatively interconnecting a heater to a source of energy when the output effect of the heater is below a predetermined setting of the control device and to disconnect the heater from the source of energy when the output effect of the heater is above the predetermined setting of the control device, the control device operating an indicating light to indicate that the output effect of the heater is still above a certain value when the control means is in an "off" setting thereof.