Abstract: A crawler type vehicle driving apparatus which is designed to be compact in construction and readily be disassembled and reassembled. The apparatus comprises a rotating assembly having a bore extending along its rotational axis, a motor housing fixedly supported by a stationary frame structure and accommodated in the bore of the rotating assembly through bearings for rotatably supporting the rotating assembly, a hydraulic motor accommodated in the motor housing to be removed from one side of the rotating assembly, and a reduction gear unit detachably attached to the other side of the rotating assembly in driving engagement with the hydraulic motor.

Abstract: A feed beam for a rock drill comprises a box girder (13), a saddle (10) slidable along the box girder, and two power units (20,20a) inserted into the ends of the box girder.Each power unit comprises a pair of fixed pulleys (22,24) located outside the end of the box girder, an hydraulic jack (26) carrying a pair of movable pulleys (28,30) within the box girder, and a cable coupled between the power unit and the saddle and passing over the four pulleys.

Abstract: A miniature volumetric pump for determining the thermodynamic characteristics of oil effluents comprising a hollow cylinder and a piston moving in a straight line relative to the cylinder. The pump is characterized in that the piston is stationary and secured to the pump frame and in that the cylinder can move in a straight line with respect to the frame and is adapted to receive the piston in sealing-tight manner in its bore, the pump comprising a screen device for moving the cylinder.

Abstract: A plastic air cylinder assembled by the specific combination of a plurality of metal tie rods, inside and outside nuts, a resilient and compressible member and supporting plates whereby the plastic cylinder tube is permitted to expand more than the metal tie rods.

Abstract: An improved piston structure for Diesel and like reciprocating piston engines is provided having a top and foot, a sealing section on said piston connecting said top and foot, a guide section articulatedly connected to said sealing section through trunnion means on a connecting rod, said guide section having a sliding shell in the form of a collar at its periphery surrounding a wrist pin in the region of its bearing points, and at least one rib for each bearing side in the form of a chord connected to said shell in the region of the bearing point.

Abstract: A coffee brewing and serving machine is provided with an upper housing portion from which hot water is dispensed in a downwardly flowing stream through a removably mounted, large funnel containing a large foraminous basket in which is disposed filter paper and coffee grounds. Below the outlet of the funnel is a lower housing portion containing a coffee tank having a vertical wall dividing the tank into two substantially equal sized coffee holding urns. An urn cover is supported on an upper portion of the lower housing portion over the coffee tank. The urn cover has an orifice in vertical alignment with, and below, the funnel outlet. Further there is a channel-shaped diverter trough on the underside of the cover below, and in alignment with, the cover orifice.

Abstract: A cup and cover turnover mechanism for muffin grilling griddles having a cup flight which straddle mounts spaced roller chains of a cover and hearth flight, wherein the conveying chains of each of said flights engage identical sprockets which mount for rotation about the turnover axis of the griddle and coordinate each cup thereon in fixed relation with a cover as the muffin is bottom-grilled and turned over on the pitch circles of said sprockets for top-grilling on the hearth flight of the griddle.

Abstract: A dewatering press which is particularly suited for use on a self-propelled vehicle designed to field process alfalfa for obtaining therefrom fiber and protein components and a deproteinized liquid component which is simultaneously applied on the field as the vehicle advances. The dewatering press includes a pair of conical pressure members mounted in a frame assembly which provides outward and downward pivotal movement of the conical members to afford access to the interior of the press. Material to be pressed is charged downwardly between the pressure members as they are rotated slowly by motors mounted in the frame assembly, and after having passed through a pressing zone located below the rotational axis of the conical members, the pressed material is discharged outwardly by a deflector mounted between the conical members. Expressed juices are collected in a pan which extends along the lower periphery of the pressure members.

Abstract: An apparatus for die stamping the end of battery cell containers which includes a die holder, a hollow tube for engaging and guiding the container end with the die, a hammer for impacting the end of the guided and engaged container end with the die and an air cylinder for first engaging the hollow tube with the container and for engaging the container end with the die and, when the container end is so engaged, for actuating the hammer for impacting the container end.

Abstract: This relates to an apparatus and method for marking printed circuit boards with numeric, alphabetic and/or symbolic indicia. Insertion of a printed circuit board causes a plurality of punches to come to rest on the board. Further insertion releases a striking hammer from its rest position permitting it to fall on the punches thus impressing the required markings on the board. The downward motion of the hammer causes a motor to be activated which returns the hammer to its rest position after which the motor will be turned off.

Abstract: Method and apparatus for use in numbering a series of successively fed documents with consecutive serial numbers and corresponding check digits, including weighted, non-sequential check digits. The check digits are independently applied by a single, engraved wheel mounted on the periphery of a rotating sleeve and positioned by an eccentrically-mounted electronically-controlled stepping motor, with the consecutive serial numbers being applied by a conventional consecutive decimal numbering head mounted to a separate, rotating shaft. Multiple check digit wheels and/or multiple consecutive decimal numbering heads may be employed.

Abstract: A multiple-color, offset rotary press is disclosed wherein each plate cylinder carries two printing plates, with one of them wrapped around a larger diameter portion of the plate cylinder and the other around a tube slidably fitted over a smaller diameter portion of the cylinder. A shaft secured to the tube and extending coaxially from one end of the plate cylinder, and an axle extending coaxially from the other cylinder end, are mounted on frame means for independent rotary and axial motion. A pair of driven helical gears are mounted respectively on the shaft and the axle for simultaneous rotation therewith but for axial motion relative to same and are meshed respectively with a pair of driving helical gears fixedly mounted on the opposite axles of a corresponding blanket cylinder. The positions of the printing plates are separately adjusted in the circumferential direction by causing axial motion of the driven helical gears, and in the axial direction by causing axial motion of the shaft and the axle.

Abstract: A constant printing pressure mechanism for a label printing machine: in one embodiment, a pressure applying roller is attached to the free ends of the yokes or printing levers that support the printing head; a resilient pressure receiving member which is pivotally supported on the machine frame and is abutted by the pressure roller; when the hand lever is squeezed, the pressure roller is pressed to the pressure receiving member; when the force of the pressure roller both pivots the receiving member a permitted maximum distance and overcomes the compressive stress in the resilient pressure receiving member and deflects the member, then the printing stroke is effected; in another embodiment, the pressure applying roller is on the frame and the resilient pressure receiving means is on the hand lever; the pressure receiving means comprises: a supporting member attached to a hand lever; a pressure controlling member which is pivotally secured to the hand lever; a pressure receiving piece having a cam surface on th

Abstract: An inking wheel having a ring formed of firm inking material, said ring being mounted upon a hub by means of a concentric, radially yieldable support comprising a concentrically disposed coil spring, said concentric spring having a pair of outer coils supporting the ring and an inner lesser diameter coil adapted to be frictionally seated on the hub, the inner and outer coils joined integrally by a pair of bridging coils at opposite ends of the inner coil with the resilience being provided thereby.

Abstract: There is disclosed an ink roller adapted to be used in a printing apparatus. The ink roller includes a hub having a roll-mounting section, a flange section, a first stub shaft adjacent the first flange section and a second stub shaft disposed opposite the first stub shaft and joined to the roll-mounting section. A second flange section telescopically receives and is axially aligned with the roll-mounting section. The second flange section is joined to the hub preferably by ultrasonic welding. There is also disclosed method of making the ink roller.

Abstract: 1. A helicopter destructor comprising in combination,a hydrophone channel,a microphone channel,a barometer channel,an AND gate connected to the outputs of said hydrophone, microphone, and ometer channels,an explosive means, andmeans connected to the outputs of said hydrophone channel and said AND gate for detonating said explosive means when a trio of signals are simultaneously applied to the respective inputs of said AND gate.

Abstract: There is described a mobile apparatus for laying of railway tracks. The apparatus includes a working tool carrying chassis capable of laying of new ties, a wagon for transporting and handling of material necessary for the track laying and a carrying bridge structure having one end carried by a rolling support and the other end comprising a rolling support and at least one supplementary retractable rolling support which is adapted to bear on the track bed. The carrying chassis is suspended above a working zone from the carrying bridge structure. The device is characterized in that the carrying bridge structure includes a wagon having only a single rolling support disposed at its end and provided with the aforementioned retractable supplementary rolling support and a longitudinally extending raised chassis which is pivoted at its other end to an overhanging bracket extending from the wagon which transports and handles the material.

Abstract: An overhead monorail conveyor whose inverted U-shaped rail has flanges provided with inwardly extending lower marginal portions to provide tracks for the wheels of a vehicle having an inverted U-shaped frame which surrounds a portion of the rail. The wheels are mounted on brackets which extend at a level below the marginal portions of the flanges and thereupon upwardly into the interior of the vehicle frame. The motor which drives the vehicle is mounted in the frame in the interior of the rail, the same as the conductors which supply electrical energy and the toothed rack or racks which mate with several gears driven by the motor. The interior of the rail further confines and shields other sensitive components of the conveyor, such as electric switches, proximity detectors, contacts which slide along bus bars, centering rolls for the frame of the vehicle, and devices for biasing the motor-driven gears against the toothed racks.

Abstract: In accordance with the present invention a railway hopper car unloading arrangement is provided, including at least one hopper having hopper slope sheets extending downwardly and inwardly. A standard outlet frame is attached to the inner ends of the hopper slope sheets. A removable adapter is attached to the outlet frame. The adapter includes an adapter mounting flange and a divider extending longitudinally of the car, which divides the adapter into a pair of transversely spaced adapter outlets or chutes. The adapter further includes adapter side walls and end walls, the lower ends of which define transversely spaced adapter chutes. A generally horizontally extending gate is movable between open and closed positions relative to each adapter chute. In addition, the adapter includes boot attachment means located below each adapter outlet for attachment of an unloading boot for each adapter outlet.

Abstract: A compact agricultural planter unit is provided for narrow row crops. The unit includes a pair of double disk furrow openers in combination with adjustable depth gauge wheels. The disks and wheels are carried by frame structure positioned between the wheels and are rotatably mounted on pivots located radially inwardly of the wheel peripheries. Manually adjustable structure for selecting the furrow depth or position of the gauge wheels relative to the disks extends slightly radially outwardly beyond the wheels.

Abstract: The invention comprises a method of and machine for stitching a thong to an upper in a machine for the manufacture of footwear in which the vamp is sewn to the upper by leather thongs, in which a barbed needle on a ram reciprocating in a fluid operated cylinder is passed through preformed pairs of shaped holes in the material to be thonged, applying a thonging thread to the needle and applying fluid to one end of the cylinder to draw the needle and the thonging thread through the vamp and the upper, withdrawing the needle and moving the material to receive the needle through a succeeding pair of holes on the material and applying fluid to the opposite end side of the ram and re-passing the needle and thonging thread through the vamp and upper for succeeding stitches, an air line being connected to each end of the cylinder with a control valve to regulate the air flow.

Abstract: A knife assembly for a fine gauge tufting machine comprises a rectangular clamping bar and a series of knife blocks mounted side by side on the knife bar. Each knife block carries a number of knives mounted in parallel grooves in the knife block machined in a direction to present the knives to loopers of the machine at the desired cutting angle. The knives are retained in each knife block by a plate and clamping screws which extend through the plate to engage the edges of the knives. Each knife block has a rearwardly extending peg which is clamped in a hole in the knife bar with the knife block orientated to present the knives to the loopers at the desired pressing angle.

Abstract: A throat plate having a anti-haloing member attached thereto to separate the work limb of a loop of needle thread from the take-up limb during the setting of a stitch thereby preventing the work limb from being drawn up through the material being sewn by frictional interengagement with the take-up limb.

Abstract: Prefabricated rigid insulating panels of great length, made of a fiberglass reinforced prestressed foam enclosed in a gas tight envelope and covered on their inner face by a folded metal membrane are glued directly to the cavity walls of the load bearing structure of a cryogenic tank by means of variable thickness adhesive mastic strips, which also separate channels for a gas circulation against the panels' back face. The beveled edge surfaces of adjacent panels are rigidly bonded under pressure. Panel handling, gluing operations, and membrane welding inside the closed space of a tank are done using telescopic towers fitted with four mobile arms, one of them supporting a worker-carrying bucket. Complete self standing inner tanks may also be assembled outside and inserted into the cavity of a vessel before it is covered over.

Abstract: A stabilizing system for a crane vessel of the twin hull semi-submersible type having a working platform supported above sea level by columns on submersible hulls. Water ballast compartments above sea level on the corner columns are discharged selectively in order to stabilize the vessel during handling of heavy outboard loads by cranes. The water is discharged through controlled valves of special construction. This control is regulated in dependence of measured values of the moment of force applied on the vessel by the crane load, and effects the operation with the help of a computer.Lower water ballast compartments in the columns have an additional "passive" function and the water can be discharged therefrom by pressurized air or by pumping it into the upper ballast compartments.

Abstract: A towable, swimmer-controlled, aquatic plane device includes an elongated wing element having sections symmetrical about a transverse center line and a fin element also having sections symmetrical about a transverse center line, the fin element being removably attached at its transverse center line to the wing element at its transverse center line with the fin element sections extending vertically above and below the wing element. Openings are provided in each fin element section adjacent its leading edge and adjacent the wing element for attaching a tow rope. Openings are provided in each fin element adjacent its trailing edge which form hand grip portions by which a swimmer can steer the device in any one or more of four directions, i.e., down for diving, up to plane on the surface of the water, or banking for turning left or right.

Abstract: A sliding boat having supporting members respectively connected to opposite sides of the hull and projecting therefrom in cantilever fashion while carrying a plurality of water sliding foils at the free end of said supporting members. Each of the sliding foils comprises a plurality of relatively long and narrow strips extending in the longitudinal direction of the boat and being spaced from each other in the transverse direction of the strips so as to form a gap there between.

Abstract: Improved apparatus for the continuous coating of one side only of a metal strip with molten coating metal, more particularly, one side galvanizing of a ferrous metal strip. Characteristics of the invention are (1) an atmosphere controlled entry chute through which said metal strip passes into the molten coating metal, (2) a deflector roll which guides said strip into and out of said molten coating metal, where the width of said deflector roll is less than the width of said strip and said strip is only slightly immersed below the surface of said molten coating metal, (3) movable guide means adapted to shift laterally with corresponding movement of said strip, and (4) gas jets secured to said guide means and directed towards edges of the uncoated surface of said strip projecting beyond said deflector roll to prevent molten metal from contacting said uncoated surface.

Abstract: The present invention is an improvement in a machine described in U.S. Pat. No. 4,046,106 for applying a daub of liquid resin to the threads of a bolt-like fastener. In the unimproved machine the daub was applied by moving the fasteners tangentially to a disc-like applicator wheel. The improvement includes a number of notches in the circumferential edge of the applicator wheel. The fasteners engage the notches with the result that the patch of resin applied extends around the threaded fastener farther in the circumferential direction.

Abstract: A protected conveyor for a spray chamber or spray booth is provided with a pressurized housing and an air curtain means which substantially isolates the conveyor from the deleterious fluids within the spray booth and substantially isolates the articles from droppings from the conveyor. More specifically, a blower supplies air under pressure to a plenum connected to a nozzle means which discharges a thin curtain of air transversely across a slot in the housing wall and transversely across depending conveyor hangers extending downwardly through the slot. The blower also supplies air under pressure to the housing to provide air discharge out of the housing slot. The transverse air discharge combines with and redirects the air discharge through the slot as common continued air movement transversely away from the conveyed articles and toward an external air exhaust from the booth. The housing, conveyor and air curtain means are formed in an inexpensive manner.

Abstract: An apparatus for producing preforms for the production of optical fibers by plasma coating and drawing. A plasma stream produced with the aid of a radio frequency generator is caused to successively pass through three zones in the first of which a mixture of fluidized powders of two materials of appropriate composition is injected and completely vaporized. In the second zone an oxidizing gas having a mixing action is introduced into the deeply cooled stream. The materials and gas react with each other to form microseeds. The powders contain high purity silicon and at least one doping element of the group comprising Al, Ge, B. Ti and Zr. In the third zone an inert gas is introduced and deposition of substance is effected on substrates suitably arranged with respect to the path followed by the plasma stream.

Abstract: An arrangement and photometer for measuring and controlling the thickness of optically active thin layers wherein the axis of the measurement light beam coming from the measurement light source is directed to the measurement object and a referenced light receiver, independent of the optical properties of the measurement object, is associated with the measurement light beam. The output signal of the referenced light receiver is mixed with a trigger stage for a phase sensitive photometer amplifier and is fed to a compensation circuit for the equilization of brightness variations in the measurement light source.

Abstract: A vacuum vapor-deposition apparatus comprising a turntable for holding some substrates subjected to vapor-deposition, on its circumferential portions; a plurality of evaporating boats disposed opposite to the circumferential portions of the turntable; a plurality of SCR boat power sources for respectively heating the plural evaporating boats; and at least one quartz deposition monitor provided on the turntable, wherein the turntable is rotated for vacuum vapor-deposition so that the evaporated materials from the respective boats are periodically deposited on some substrates to form the start of the successively evaporated materials.

Abstract: An apparatus used in a dairy barn that facilitates access to the dairy animals for milking, which comprises a fixed platform on which the animals stand during milking, a fixed support surface adjacent and lower than the platform, a floor adjacent the platform and above the support surface that is selectively elevatable between a raised position and a lowered position, means for raising and lowering the floor, and means for restraining the animals on the platform so that they may be milked by the operator. The platform has a configuration that, when the floor is in its lowered position, allows the operator to milk the animals while he is standing substantially upright. The animals are able to approach or leave the platform when the floor is in its raised position.

Abstract: In a fowl-feeding machine of the cable and spaced disk type, the improvement consisting in that pressing and positioning spacers urge from the top the disks as they travel on the trough bottom wall so as to maintain such disks in position. By so doing, no fodder build up can be experienced locally and it is possible to prevent fodder spillage.

Abstract: A bird feeder having an opened topped hemispherical bird feed container suspended below a hemispherical cover which extends laterally beyond the perimeter of the container, the suspension for the container being pivotally mounted closely adjacent the innermost central portion of the hemispherical cover whereby upon tilting of the cover, at least the lowermost portion of the cover will overlap the adjacent portion of the container.

Abstract: A boiler comprising a pressure vessel containing a volume of oil, a heat exchanger adapted to heat the oil within the pressure vessel and a water injection unit for injecting water into the oil volume and the pressure vessel for generation of steam.

Abstract: 1. In combination with a bomb or similar projectile intended to move rapi through the air and having aerodynamic characteristics such that the longitudinal axis of said projectile will be substantially coincident with its trajectory, a dipole antenna mounted on a cylindrical projection which extends from the nose of said projectile, said antenna comprising a pair of extending arms normal to said longitudinal axis and on opposite sides thereof, a proximity fuse carried by said projectile, and means connecting said antenna to said fuse.

Abstract: A mixed-flow feedwater heater having a regulating device is disclosed including a feedwater tank having a deaerating dome. Steam is conveyed from a low pressure steam drum to a feedwater tank to heat and deaerate the feedwater. Feedwater is supplied from the feedwater tank either to the low pressure steam drum or to an evaporator. The water level in the low pressure steam drum is regulated to a desired level. The feedwater tank is connected to the steam drum by a steam pipe having a pressure-regulating valve which is subjected to the pressure in the mixed flow feedwater tank. The valve controls the pressure in the feedwater tank so that the pressure does not exceed a pre-determined value.

Abstract: A compression ignition direct injection internal combustion engine comprising at least each one cylinder, a piston and an injection nozzle, the cylinder having an inlet port for inducing rotation of the incoming air about the axis of the cylinder and a combustion chamber or cavity in the form of a body of rotation disposed in the piston, said chamber having, below the crown of the piston, a constriction which divides the chamber into an upper and a lower part.

Abstract: A piston having an uncooled annular insert adjoining a main combustion chamber between piston and cylinder cover, combustion cavities arranged in the crown of the piston and an injection passage opening into the combustion cavities wherein, in the zones covered by the annular insert (5), laterally of the injection passage (8), outside the combustion cavities (6), the distance between the lower edge of the annular insert (5) and the crown surface of the piston (1) is increased by 0.15 to 0.7% of the piston diameter in comparison with the distance between the main surfaces of piston (1) and the cover of the cylinder (2).

Abstract: Apparatus for controlling fuel supply to an internal combustion engine includes means for interrupting the fuel supply, which means includes two devices operable independently of engine operating conditions. One of the devices is operated when a given engine speed and/or a given vehicle speed is exceeded with engine fuel supply regulating means in a no supply condition. The other of the devices is operated when a predetermined vehicle speed is exceeded.

Abstract: To control the ignition timing in a multicylinder engine, the computer output signal which controls the current flow through the ignition coil for generating the spark in the first cylinder is delayed and then applied to the ignition coil controlling the spark in a subsequent cylinder. The computer output signal is delayed by passing through a shift register whose clock input is derived from a pulse generator generating a pulse for each predetermined incremental angular rotation of the crankshaft. If a single ignition coil and a distributor are used, the computer output signal and the delayed computer output signal are applied to an OR gate whose output controls a switch controlling the current through the ignition coil. When more than one ignition coil is used, the computer output signal is applied to a switch controlling the current through the first coil, the delayed computer output signal to a switch controlling the current to a second coil.

Abstract: In an electronic ignition control apparatus for an engine, an actual optimum spark advance angle for activation of a spark plug is determined as a value defined by a linear equation representing a relationship between an optimum spark advance angle and an amount of air sucked into the engine in consideration with an actual rotation speed by using a stored optimum spark advance angle defined by a reference linear equation representing a relationship between the stored optimum spark advance angle and an amount of the sucked air in consideration with a predetermined rotation speed.

Abstract: A heat-exchanger system for the charging-air of a low-compression reciprocating piston internal combustion engine operating with exhaust gas turbo-supercharging, which is equipped with a first charging-air-water heat-exchanger that during the starting and partial load operation supplies the heat energy of a heater device to the charging air and which can be connected to the cooling water circulation of the internal combustion engine, and with a second charging-air-water heat-exchanger which is connected to the cooling water circulation external to the engine; the two charging-air-water heat-exchangers are thereby adapted to be traversed in parallel by the charging-air while a control system enables a stepless control of the charging air flow through the individual heat-exchangers as a function of the temperature of the charging air upstream of the cylinders and of the operating condition of the internal combustion engine.

Abstract: An air-fuel ratio control apparatus for an internal combustion engine has an air valve disposed in an intake passage downstream of a throttle valve to cooperate therewith to define an air pressure chamber and operative to maintain a substantially constant pressure therein. A fuel circuit includes a fuel discharge port open to the intake passage and a fuel-metering orifice operatively associated with the air valve such that the fuel-flowing section of the orifice is varied in proportion to the air-flowing section of the air valve. A constant differential fuel pressure valve is disposed in the fuel circuit to maintain a substantially constant fuel pressure difference across the fuel metering orifice during normal engine operation. The differential fuel pressure valve is mechanically operatively connected to a piston-cylinder assembly into which the fuel pressure upstream of the fuel-metering orifice is introduced.

Abstract: An inexpensive anti-theft control device for an ignition fired internal combustion engine comprising a resistor and settable switch connected in series between the interruptor circuit from the ignition coil and ground whereby, when the switch is closed, a portion of the current normally necessary to induce sufficient voltage in the coil to properly fire the spark plugs is drained off.

Abstract: A portable emergency ignition unit which will enable a person to get a vehicle to a service shop when the electronic ignition, or the points, condenser or coil has failed, or when the ignition key has been broken or lost. This portable ignition unit has solid state integrated circuit and transistor which give the unit a more reliable and hotter spark. The circuitry comprises a simple hookup of one lead wire going to the ground terminal of the battery, another lead wire going to the positive terminal, a third lead wire going to the starter solenoid and lead wires going to the distributor. To start the engine, the starter button on the emergency unit is depressed so that 60,000 volts is applied by the ignition unit to the rotor inside the distributor cap, which voltage the rotor will distribute to the spark plugs in firing order sequence. Then when the starter button is released, a voltage of 30,000 volts is continued to the rotor and thereby to the spark plugs.

Abstract: The present invention discloses a system which utilizes the storage action of capacitors and the characteristic of the turn-off operation due to a potential difference between the base and emitter of a transistor, and immediately after a primary short-circuit current flowing through a primary winding of an ignition coil has reached a maximum, that is, immediately after a forward induced voltage in the primary winding has reached a maximum, the primary short-circuit current is cut off in accordance with information in which the forward induced voltage in the primary winding is at its maximum to always effect the ignition operation immediately after the primary short-circuit current is at its maximum.

Abstract: A starting system for an internal combustion engine includes an automatic temperature dependent delay timer which includes an output transistor and a thyristor connected across the base-emitter of the transistor so that the transistor is turned off when the thyristor is conducting. Firing pulses for the thyristor are derived from a programmable unijunction transistor which has associated with it a timing capacitor and a thermistor such that the charging time constant of the capacitor decreases with increasing temperature. The length of time for which the transistor remains on after the circuit is energized decreases with increasing temperature.