Abstract: An electrical switch construction and method of making the same are provided, the switch construction having a support carrying a pair of spaced apart first and second fixed contacts and a movable switch blade unit carrying a contact unit for being disposed in contact with the first fixed contact and out of contact with the second fixed contact when the switch blade unit is in a first position thereof and for being disposed in contact with the second fixed contact and out of contact with the first fixed contact when the switch blade unit is in a second position thereof.

Abstract: A system for monitoring a level of material held in a confining means, a device therefor and methods of making the same are provided, the system comprising a rotatable reel, an electrically operated motor operatively interconnected to the reel for causing rotation of the reel in either direction of rotation thereof, a flexible support wound on the reel and having a free end, a probe operatively interconnected to the free end of the support to be carried thereby, a brake operatively interconnected to the reel for holding the reel stationary when the brake is in one condition thereof, and a control unit operatively interconnected to the motor and to the brake for causing the brake and the motor to raise and lower the probe by winding up the support on the reel and unwinding the support from the reel, the motor comprising an electrically operated stepper motor.

Abstract: An oscillating crystal force transducer and method of making the same are provided, the transducer comprising support structure, a plate-shaped piezo-electric crystal having opposed sides and a peripheral edge extending between the opposed sides, and two seating members carried by the support structure and respectively engaging the peripheral edge of the crystal and arranged to apply a force to the crystal along a line extending through the crystal from one of the seating members to the other of the seating members, the support structure comprising a looped spring member having opposed ends spaced from each other to define the mouth of the looped spring member and respectively carrying the seating members whereby the crystal is disposed in the mouth of the looped spring member between the seating members thereof.

Abstract: A temperature regulating control unit and method of making the same are provided, the unit comprising a RTD temperature sensor, a unit for applying electrical signals to the sensor, and a microcomputer for receiving digital signals from the sensor in relation to the temperature being sensed by the sensor, the unit for applying electrical signals to the sensor applying a varying voltage to the sensor.

Abstract: The combination of a heating element and a control unit therefor and methods of making and of operating the same are provided, the heating element normally being adapted to be operated by the continuous full wave pulses of a certain high voltage alternating current source and the control unit being operatively interconnected to the heating element for operatively interconnecting the heating element to a high voltage alternating current source, the control unit having an arrangement for operating the heating element with a certain repeating pattern of skipped full half-wave pulses of the source when the source has a higher voltage than the certain source.

Abstract: A control device, switch unit therefor and methods of making the same are provided, the electrical switch unit comprising a switch having a movable actuator, a lever pivotally carried by the switch unit and having one end adapted to be operatively interconnected to a movable part of a control device so as to be pivoted by the movement thereof, the lever being operatively interconnected to the actuator to operate the switch between the different conditions thereof in relation to the pivoted position of the lever, and a pair of mounting plates respectively having holding structure that hold the switch between the plates and respectively having pivot structure that pivotally mount the lever between the plates whereby the plates, the switch and the lever form a self-supporting switch unit.

Abstract: A differential pressure transmitter, a pneumatically operated square root extracting device therefor and methods of making the same are provided, the transmitter having a rod operatively interconnecting a movable wall with a cam roller to cause the roller to roll on a flat surface as the value of the pressure in an output chamber defined by the movable wall changes, the rod and the movable wall respectively having universal joint units snap-fitted together to provide for universal movement therebetween while movement of the wall causes the roller to roll.

Abstract: A cooking apparatus, a door latching construction therefor and methods of making the same are provided, the cooking apparatus including a frame, a cooking chamber carried by the frame, a heating unit carried by the frame and being adapted to be actuated to heat clean the chamber, a switch for permitting the heating unit to heat clean the chamber only when the switch is actuated, a movable door carried by the frame for opening and closing the cooking chamber, a movable latch member carried by the frame and being movable between a non-latching position thereof that permits the door to be opened and closed and a latching position thereof that locks the door in its closed position if the door is in its closed position at the time the latch member is moved to the latching position thereof, and a drive unit carried by the frame and being operatively interconnected to the latch member to move the latch member between the positions thereof, the latch member being movable from the non-latching position thereof to a th

Abstract: A differential pressure transmitter, a pneumatically operated square root extracting device therefor and methods of making the same are provided, the transmitter comprising a unit for producing an output pneumatic signal from a pneumatic source in relation to the air velocity pressure of air flowing in a passage, a unit that senses the difference between the total pressure and the static pressure of the air flowing in the passage, and a unit for extracting the square root of the air velocity pressure of the air from the pneumatic output signal as the peneumatic output signal is being produced so that the pneumatic output signal is substantially linear with respect to the air velocity of the air flow in the passage whereby the transmitter comprises a linear air velocity transmitter, the unit for extracting the square root comprising a cam having a cam face that defines at least part of the involute of a circle.

Abstract: A control system and method of operating the control system are provided, the system having a supervisory circuit for detecting failure of the system and disabling a high energy control circuit of the system, the supervisory circuit having a capacitor therein for sustaining an on condition of a supervisory transistor that is in series with an output relay driver transistor of the high energy control circuit, and a temperature sensing unit that is disposed intermediate a microcomputer of the system and the supervisory circuit for continuing the charging of the capacitor only as long as the temperature sensing unit is sensing an output temperature effect of a heating unit of the system that is below a predetermined high temperature limit for the system and that terminates the charging of the capacitor when the sensed temperature is above the predetermined high temperature limit.

Abstract: A fuel control valve construction, parts therefor and methods of making the same are provided, the construction comprising a housing having an inlet adapted to be interconnected to a fuel source and an outlet adapted to be interconnected to a main burner, the housing having a pilot outlet adapted to be interconnected to a pilot burner for the main burner, the housing having a pilot valve seat and a main valve seat for interconnecting the inlet respectively with the pilot outlet and the main outlet, the housing having a movable pilot valve member for opening and closing the pilot valve seat and a movable main valve member for opening and closing the main valve seat, the housing having a movable lever carrying the pilot valve member and the main valve member and having a manually operable actuator for controlling the operating positions of the lever.

Abstract: A fuel control system, throttle valve unit therefor and methods of making the same are provided, the system comprising a burner, a source of fuel for the burner, and a throttle valve unit for interconnecting the source to the burner, the throttle valve unit having a movable valve member and a valve seat controlled by the valve member, the throttle valve unit having an electrically operated unit operatively associated with the valve member to control the position of the valve member relative to the valve seat so as to control the flame height at the burner, the electrically operated unit comprising a fixed magnet unit and a movable magnet unit each of which is adapted to provide a magnetic field that will react with the other magnetic field, one of the magnet units having an electrical conductor that is adapted to vary the force of its magnetic field in relation to the magnitude of an electrical current passing therethrough whereby the valve member is adapted to be positioned relative to the valve seat in rela

Abstract: A fuel control device, system using the device and method of making the same are provided, the device comprising a housing having an inlet for being interconnected with a fuel source and an outlet for being interconnected to a main burner, the housing having a main valve seat between the inlet and the outlet and a thermostatically operated valve member for opening and closing the main valve seat, the housing having an annular heater pilot valve seat surrounding the main valve seat and being opened and closed by the thermostatically operated valve member at the same time that the thermostatically operated valve member is opening and closing the main valve seat, the housing having an annular auxiliary fuel supply valve seat surrounding the heater pilot valve seat and being adapted to be opened and closed by the thermostatically operated valve member at the same time that the thermostatically operated valve member is opening and closing the main valve seat and the heater pilot valve seat, the housing having a pa

Abstract: Electrically operated appliance controls and methods of making the same are provided, one control comprising an electrically operated device for providing two different functions of the device, an electrically operated visual display unit, and a manually operated selector unit electrically interconnected to the device and the display unit for selecting a desired function of the device and for setting the device to provide that selected function in a desired set manner thereof as being indicated on the display unit by such operation of the selector unit. The selector unit has a manually operated start actuator which when actuated will cause the device to begin to produce the selected function thereof and in that selected set manner thereof.

Abstract: An exhaust gas recirculation valve construction and method of making the same are provided, the valve construction comprising a housing provided with an inlet and an outlet separated by a valve seat, a movable valve member carried by the housing for opening and closing the valve seat and an electrically operated stepper motor carried by the housing and being operatively interconnected to the valve member for positioning the valve member relative to the valve seat. The valve member and the valve seat are arranged so as to be reverse acting and a spring is operatively interconnected to the valve member to tend to move the valve member to its closed position with the valve seat upon loss of electrical current to the motor.

Abstract: An apparatus for automatically brazing the opposed ends of a capillary tube respectively to connecting parts of a bulb and a diaphragm unit and a method of making the apparatus are provided, the apparatus comprising a rotatable table and a plurality of work stations disposed in spaced apart relation about the table and each having an operating device, the table having a plurality of fixtures each being adapted to hold an assembly of the bulb and diaphragm unit in a fixed relation relative to each other with the capillary tube assembled to the connecting parts thereof, the table being adapted to index through the work stations so that the devices at the work stations can each perform its specific operation on the respective assembly disposed at that particular station during a predetermined dwell time in the movement of the table, the device of one of the station comprising a movable arm for applying a flux to the assembly, the device of another of the stations comprising a movable arm for preheating each asse

Abstract: A primary gas furnace control including a thermostatically controlled intermittent ignition system, the control being effective to monitor and control main gas valve action through use of flame rectification. The control features a slight delay on main valve dropout with flame failure and an extension of the ignition source into the main burner cycle to prevent nuisance recycling. If desired, the control may also include time pilot valve, thermostat resettable, lockout as well as prepurge capability for use in applications requiring a furnace combustion chamber purge prior to an ignition cycle.

Abstract: A control device, switch unit therefor and methods of making the same are provided, the electrical switch unit comprising a switch having a movable actuator, a lever pivotally carried by the switch unit and having one end adapted to be operatively interconnected to a movable part of a control device so as to be pivoted by the movement thereof, the lever being operatively interconnected to the actuator to operate the switch between the different conditions thereof in relation to the pivoted position of the lever, and a pair of mounting plates respectively having holding structure that hold the switch between the plates and respectively having pivot structure that pivotally mount the lever between the plates whereby the plates, the switch and the lever form a self-supporting switch unit.

Abstract: A vehicle cooling system subassembly, parts therefor and methods of making the same are provided, the subassembly comprising an outlet housing having an opening therein, and a vehicle type thermostat disposed in the opening of the outlet housing and having a housing provided with a valve seat that is controlled by a movable valve member which is interconnected to a temperature responsive device that is carried by the thermostat housing, the outlet housing having a positioning device thereon, the thermostat housing having a positioning device thereon engaging the positioning device of the outlet housing to rotationally orient the thermostat in the opening of the outlet housing in a desired rotational position thereof, the outlet housing having a slot therein, the thermostat housing having a tab extending outwardly therefrom and wedgingly disposed in the slot to hold the thermostat in the opening of the outlet housing in the desired rotational position thereof.

Abstract: A sheet of mulch material and method of making the same are provided, the sheet of mulch material comprising a sheet of polymeric material having openings passing therethrough and opposed sides one of which is to face the ground on which the sheet of mulch material is to be disposed, and a sheet of fabric material being coextensive with and being secured to the one side of the sheet of polymeric material and overlapping the openings thereof to tend to prevent plant growth through the openings.