Abstract: A substantially U-shaped traveller and a substantially V-shaped traveller for ring spinning machines equipped with a substantially frusto-conical ring, each of these travellers having a guide or guiding portion which comprises externally a quadrant arcuate segment part and internally a substantially straight section or part.

Abstract: A sliver guide has a restrictor and deflectors for imposing uniform transverse forces on a sliver immediately before the latter is supplied to a feed roller in an open-end spinning unit, thereby spreading the sliver and loosening the core thereof. The sliver guide serves to prevent grain variations and neps that are otherwise caused in the spun yarn by the hard core and twists of the sliver which naturally form as the latter is being produced.

Abstract: A yarn draw off tube for an open-end spinning unit which improves the twist transmission to a fiber ribbon in a spinning rotor. The yarn draw off tube is provided with a yarn inlet on the top wall thereof and a yarn outlet on the lower side wall thereof, and the yarn inlet is eccentric from the center in a direction opposite to the yarn outlet. In the spinning operation, a twist imparted to a yarn drawn off from the spinning rotor can smoothly be transmitted to the root portion thereof. Thereby, yarn breakage is restrained and a yarn of good appearance and strength can be obtained.

Abstract: An exhaust cleaner and burner system for use with a diesel engine has a housing with an inlet at one end for receiving exhaust gas from an engine and an exhaust outlet at its opposite end with a particulate filter positioned therein intermediate the inlet and the exhaust outlet having an inlet face axially spaced from the inlet. A fuel burner device is operatively positioned in the housing in axial spaced apart relationship to the inlet face of the filter and is adapted to be connected to an air/fuel mixture source and has an igniter for the air/fuel mixture. A rotatable flame distributor is operatively associated with the fuel burner device whereby to direct a flame discharged from the fuel burner device incrementally across the inlet face of the filter so as to sequentially effect complete burning of collected particulates.

Abstract: A pneumatic control system for machines that provides precise incremental or continuous direction, position, velocity and acceleration control of a variety of machine functions, such as rotary or linear motions, tool positioning and the like. A compressed air supply is maintained accurately at a preselected minimum pressure necessary for a particular operation, by a digitally pulsed air flow control system. Air flow and pressure to the associated actuating mechanisms is also controlled by a digital dithering technique using individual sharp pulses of air, each of which instantly breaks the static friction of the mechanism and causes a discrete precise increment of movement, with rapid consecutive pulses providing continuous motion. The direction, amount, acceleration and speed of travel are controlled by varying the pulse width and rate of air flow and pressure as necessary and for efficiency in air consumption.

Abstract: A control system for a hydraulically driven vehicle having a variable displacement hydraulic motor connected with a variable displacement hydraulic pump in a closed loop and driven thereby.A spring-applied and fluid-released brake is mounted on an output shaft of the motor. A regulator is operatively connected to the motor for controlling the displacement thereof in response to a fluid pressure at both ports thereof. When fluid pressure at either one of the ports of the motor exceeds a predetermined level, the variable displacement motor is changed over to a high displacement position thereby generating a large braking force when the vehicle is to be stopped.

Abstract: A fluid control system (10) for controlling the torque of a fluid motor (22) and varying the flow to the fluid motor (22) has a mechanism (56) to control the torque and flow in proportion to the operator's input to a pilot operated control valve (16) that controls the fluid motor (22). The mechanism (56) controls the torque and flow of the fluid motor (22) during both acceleration and deceleration of the fluid motor (22). The fluid control system eliminates the need for special, complicated control valves.

Abstract: A heat exchanger stack apparatus for use on a remotely heated Stirling engine having a variable swashplate drive mechanism, which comprises rigidly combining a regenerator, a flexible heat exchanger, a short, rigid hot connecting duct and a cylinder. A heat exchanger stack apparatus for each cylinder of the engine is mounted on a drive mechanism housing with the regenerator adjacent to a cooler located within the drive mechanism housing. The cooler, regenerator and flexible heat exchanger are axially aligned providing a linear flowpath for the engine working fluid. Bellows and flexible tubes connected to the flexible heat exchanger provide axial and transverse flexibility to reduce thermal stresses within the heat exchanger stack apparatus.

Abstract: A power plant comprises a free piston gas generator having compression chambers and motor cylinders. A reciprocable assembly has drive pistons which are slidably received in the motor cylinders and compression pistons, each slidable for defining a variable volume compression chamber. A rotary compressor delivers air at above atmospheric pressure to the compressor chambers which are distributed into a first set and a second set. The outlets of the first set deliver air to the motor cylinders. The second set delivers pressurized air to the exhaust gas and the mixture is admitted into a power gas turbine. The temperature of the mixture of hot air and exhaust gas is increased before delivery to the turbine by a heat exchanger and a compression chamber.

Abstract: A turbo-supercharging system for an internal combustion engine of a vehicle having an air brake system wherein compressed air is preferentially supplied to the air brake system and surplus air is used for supercharging the engine. The system includes an air compressor driven by the engine, an air reservoir tank for storing compressed air therein and supplying it to a turbine of a turbo-supercharger when required, and a solenoid-operated valve disposed in a conduit interconnecting the air tank and the air compressor. The solenoid-operated valve is normally held in its block position and adapted to be changed over to its communication position when air pressure in the air brake system exceeds a predetermined value.

Abstract: A canopy extends over a canyon to provide an air channel with a lower entrance inlet and an upper discharge outlet. Sunlight passes through the canopy to effect heating of the air in the channel and airflow toward the upper outlet. A wind turbine may be driven by the discharging airflow.

Abstract: A system which stores and uses thermal and chemical energy to provide shaft power during either the charging or discharging cycles. The system is based upon a reversible transfer of gaseous fluid from a holding tank to a receiver. In operation, the fluid generates electricity or other mechanical power by doing work on a turbine or other device positioned between the tank and receiver. The fluid is heated by an external source and is particularly adapted for use with solar energy. The working fluid and an absorbent combine to form the chemical solution. In the charge cycle, heat is applied to the holding tank which distills the fluid. The fluid condenses in the condenser and is held in the receiver. In the discharge cycle, heat is transferred from the still warm holding tank to the receiver by means of piping. The fluid vaporizes and returns to the holding tank.

Abstract: A combined valve including in combination a stop valve for blocking heating steam introduced into a steam turbine and a control valve assembled in a valve casing in opposed relation. The stop valve is located upstream of the control valve with respect to the stream of the heating steam, and the stop valve and the control valve are each formed in the valve body of a main valve thereof with a bypass valve for allowing the heating steam to flow therethrough. The arrangement enables steam to flow in a volume necessary for starting the steam turbine and allows the limitations placed on the stop valve in opening same to be eliminated.

Abstract: In a cryogenic refrigerator, a refrigerant is circulated in a fluid flow path between first and second chambers by the movement of a displacer means. A slide is connected to the displacer means and reciprocated by a motor. The slide has an axial passage communicating the first and second chambers. The slide has a piston for varying the volume of gas in a third chamber during its reciprocation. The need for a separate compressor is eliminated.

Abstract: A support for a cryogen container, particularly adapted for use in spacecraft, provides a dual support. One portion of the structure supports the container in the absence of acceleration force, and the other portion of the structure supports the container in the presence of acceleration forces. The support includes a first connector means and second connector means. A first support extends between the first and second connector means. The first support is constructed of high-strength metal and is adapted at its ends for structural engagement and support of said first and second connector means. A second support also extends between said first and second connector means. The second support is constructed of material having low thermal conductivity, has a degree of elasticity, and provides support of said first connector means from said second connector means in the presence of normal forces imposed by the container and its contents.

Abstract: A storage container for shipping transportable materials at cryogenic temperatures including a vessel which opens to the atmosphere and contains a micro-fibrous structure for holding a liquified gas such as liquid nitrogen in adsorption and capillary suspension. The micro-fibrous structure comprises a core permeable to liquid and gaseous nitrogen and an adsorption matrix composed of a web of inorganic fibers surrounding the core in a multi-layered arrangement.

Abstract: In a process for the generation of a cold gas comprising introducing a relatively warm gas and a liquid cryogen into the upstream end of a mixing zone; permitting the gas and liquid cryogen to mix in the mixing zone, the amount of gas being sufficient to vaporize the liquid cryogen; and withdrawing the cold gas downstream in the mixing zone,the improvement comprising:(a) choking the gas prior to its entry into the mixing zone;(b) providing a linear mixing zone having, at its downstream end, a dead end; and(c) withdrawing the cold gas as a slipstream from the mixing zone at a point intermediate between its upstream end and the dead endprovided that the distance from the upstream end to the dead end is at least twice the distance from the upstream end to the point of withdrawal of the slipstream.

Abstract: A liquefied gas transfer apparatus having a recirculation passage for recirculating the liquefied gas sucked into a glandless pump back into the closed tank, and a device for changing the speed of the pump driving motor by suitable measures such as pole change, Y-.DELTA. switching, frequency control, primary voltage control or the like. In operation, the pump is driven at a high speed during the transfer of the liquefied gas from the tank to the containers or the like, whereas, in the period in which the transfer of the gas in not necessary, the pump is continuously operated at a low speed while recirculating the liquefied gas through the recirculation passage, thereby to prevent the evaporation of the liquefied gas in the pump to ensure smooth and safe intermittent operation of the pump, as well as prolonged life of the bearing.

Abstract: A tunnel refrigeration device includes frame members mounted substantially adjacent to an endless conveyor belt which is utilized to pass products to be refrigerated through the tunnel. The frame members are provided with apertures therein and fan means are mounted in one or more of the apertures so as to pass the tunnel atmosphere into the space between the upper and lower runs of the conveyor belt. Apertures are juxtaposed with each frame mounted fan to enable the tunnel atmosphere passed into this space to be removed therefrom and recirculated upwardly in the tunnel by means of the top mounted fans. Refrigeration is provided to the underside of products on the conveyor belt and the effective capacity of the tunnel may be increased by increasing the capacity of the top mounted fans.

Abstract: The invention relates to a heat pump with compressor, in the thermodynamic system of which, solution is used. This way varying temperature conditions take place on the heat intake and heat discharge side. Provided that varying temperature system appears also on the demand side, adapting the heat pump of the invention accordingly, the specific cooling capacity may be several times that of the traditional cooling machines under identical temperature parameters.The "wet compression" worked out in the invention, results in further increase of the specific cooling capacity, as well as it makes the competetiveness of the heat pump according to the invention indisputable in such field as for instance deep freezing.

Abstract: The refrigerant compressor of a motor vehicle air conditioning system in which the compressor is normally cycled on and off according to cooling demand is maintained continuously on or continuously off during idle operation according to a measure of the compressor duty cycle. During non-idle operation, a measure of the compressor duty cycle is compared to a reference duty cycle corresponding to a cooling demand above which it is desired to maintain the compressor on during idle operation and below which it is desired to maintain the compressor off during idle operation. At the onset of idle operation, the compressor is maintained on or off, and at the expiration of a time period corresponding to the duration of idle operation typically encountered in stop and go driving, normal compressor cycling is resumed.

Abstract: An adaptive demand defrost control system controls the length of an interval between defrost operations in accordance with the number and duration of compartment door-openings, the duration of a previous defrost operation as corrected by the temperature of the evaporator prior to defrost, and the length of time the compressor has been energized. A count is stored which is varied according to a decrementing schedule, with the decrementing schedule in turn being based upon a comparison of the corrected defrost duration with either a desired defrost duration or a range of desired defrost durations. A defrost operation is initiated when the count reaches a predetermined value. An alternative embodiment of the invention develops an indication of the ambient humidity and controls humidity-dependent apparatus in accordance with the indication.

Abstract: An automatic control for various domestic appliances has a ferrite core which surrounds the run winding for the drive motor of the appliance. The run winding represents the primary winding for the ferrite core, which has a secondary winding at which a brief output voltage is generated whenever the run winding current changes direction. This sensor in combination with a voltage zero detector circuit and post-connected logic circuitry generates a voltage pulse and a phase pulse which are respectively related to the voltage level of the drive motor and the motor output torque which is required to operate a movable member in the appliance. A microcomputer is utilized to generate a representative digital phase number which corresponds to the torque expended in the appliance. The phase number is utilized in various programs of the microcomputer for automatically controlling various functions of the appliance as well as other events in an operational sequence upon the attainment of selected torque levels.

Abstract: A single evaporator refrigerator-freezer is controlled for operation in three modes, wherein cooling of the refrigerator compartment is initiated in a first mode by operating only an evaporator fan to cool the compartment. During the first mode, the rate of temperature change within the refrigerator compartment is calculated at predetermined time intervals and if the calculated rate is positive for at least a minimum number of time intervals, a second mode is initiated by operating a compressor to cool the refrigerator compartment. A third mode, wherein the compressor is operated to cool the freezer compartment, is initiated only after the refrigerator compartment has been adequately cooled. Means are further provided for modulating the flow of refrigerant to the evaporator to allow the evaporator to be operated at a higher temperature and pressure during cooling of the refrigerator than during cooling of the freezer.

Abstract: A water heating system comprising an outdoor heat exchanger including a heat collection chamber, solar collector panels, collector fins, an evaporator for passing refrigerant therethrough to perform the heat exchange between the refrigerant and the heat transferred from the panels and fins to evaporate the refrigerant. The panels, fins and evaporator are incorporated integrally in the heat collection chamber. A variable rotational speed compressor is connected to the outdoor heat exchanger for compressing the vaporized refrigerant from the evaporator. A heat exchanger disposed on the bottom side in the water storage tank passes the refrigerant vapor from the compressor to perform the heat exchange between the water in the tank and the refrigerant vapor to condense the refrigerant vapor.

Abstract: An air conditioner for vehicles in which the temperature of an evaporator is detected and an ON-OFF control of the compressor is achieved to maintain the evaporator temperature at a pre-set temperature. The air conditioner has means for detecting the temperature of air flowing into the evaporator, and means for varying the pre-set temperature in such a manner that the pre-set temperature is increased as the detected air temperature is decreased and is decreased as the detected air temperature is increased.

Abstract: The cooling system employs a refrigeration machine having two condensers and an evaporator. The evaporator is connected in heat exchange relation with a low-temperature cooling circuit having a water accumulator. A cooling tower circuit for a higher temperature is connected with one condenser in order to cool a second load unit at a higher temperature than the first load unit.The cooling tower circuit may also be employed to cool both load units when the outside ambient temperature is below a certain value.The water accumulator may also be used as a heat source while the refrigeration machine is used as a heat pump in order to supply heat to a building heating system, for example during non-cooling periods.

Abstract: An insulated cooler for beer kegs which is specifically constructed to enclose both half-barrel and quarter-barrel kegs by inverting the top cover. The cooler has insulated bottom, top and side walls and encloses the keg with ice surrounding the same and provides an access opening through which the pump and tap assembly extends. Suitable handles are provided for carrying the keg and ice pack unit.

Abstract: A cheap, compact container for cold-storing beverage or food cans and/or bottles, comprising: (a) a pair of symmetrical, heat-insulating solid blocks with a plurality of semicylindrical indentations therein, spaced at a distance from each other and the boundaries of the blocks; (b) at least one heat-conducting solid foil continuously lining a part of the indentations in either block; (c) at least one heat-absorbing can within an indentation of either block; and (d) fastening means for connecting both blocks so that cylindrical chambers are maintained therein.

Abstract: A knitting machine includes a needle bed having a groove formed therein, a needle housed in the groove and reciprocatingly slidable therein, a needle cam, a needle cam follower mounted on the needle and engageable with the needle cam, a needle stitch selector and a needle cam disengager responsive to the stitch selector for controllably disengaging the needle cam follower from the needle cam. The stitch selector includes an electromagnetic selection station and at least one selector member which is slidably mounted on the needle bed. The selector member is responsive to the selection station and positioned thereby in one of at least two distinct positions in respect to the needle bed. The needle cam disengager includes a two-arm lever which is pivotally mounted on the bed. The first arm of the lever cooperates with the selector member and its second arm is in communication with the needle cam follower via the needle and acts operatively thereon to disengage the needle cam follower from the needle cam.

Abstract: Self actuating yarn feeding apparatus to feed yarn to a circular knitting machine when the machine makes a demand for the yarn and to cease feeding the yarn when the machine ceases demand for the yarn. The yarn is in variable circumferentially extending drive contact with the periphery of a frictionally surfaced rotating yarn feed wheel to feed the yarn to the machine. The arrangement being such that when there is a lack of demand for the yarn the degree of contact between wheel and yarn is not sufficient to feed the yarn and when there is demand for the yarn the degree of contact between wheel and yarn is sufficient to feed the yarn to the machine. The yarn extending through a yarn eyelet movable back and forth along a circular pathway in response to demand and lack of demand for the yarn by the machine to vary the degree of contact between wheel and yarn.

Abstract: For the purpose of taking down shaped knitted products from a flat knitting machine the take-down mechanism comprises an auxiliary take-down roller (18) disposed in advance of the take-down roller (16), and this can have a superimposed take-down motion intermittently imparted thereto by means of an auxiliary driving device. To increase the effectiveness of the auxiliary take-down roller (18), the last course of separating stitches formed on one needle bed can be pressed off between two successive shaped knitted pieces (43) before the taking down of a double-sided separating knitting section (45).

Abstract: A mortise lock having both a latch and a bolt which are capable of being simultaneously retracted or engaged by either a door handle or a key, and which are able to be maintained in a retracted or engaged mode as desired by the user.

Abstract: The tank fill locking system includes a special coupling adapted to fit upon the top of the tank fill pipe within the manhole. A flat top cap is removably attached to the coupling and includes aligned lock receiving openings when the handle is moved to the closed position. An upper, first, hardened steel plate overfits the fill cap within the manhole and is provided with suitable brackets to engage both the handle and the locks. Preferably, straight shackle locks are employed. A second or inner locking plate secures within the coupling below the flat cap and is also provided with a lock to lock the second plate within the coupling and thereby prevent access to the tank through the fill pipe.

Abstract: A door lock comprises, a casing; means rotatably mounted in the casing for actuating a lock bolt between the locking position and release position of the lock; means for locking said rotatable means against rotation when the lock is in its locking position, the locking means capable of relieving the rotatable means from locking when the key is inserted and the rotatable means is turned by an external action that does not route through the key.

Abstract: An arrangement for regulating a rolling mill for metal rolling, the work rolls of which are supported by guided roll shells of a lower controlled deflection roll and an upper controlled deflection roll, the roll shells being supported by means of hydrostatic pressure or support elements upon a related roll support or beam. First regulation circuits are provided for regulating the pressure of the pressure or support elements of the controlled deflection rolls. A second regulation circuit for the position of the roll shells overrides the first regulation circuits, so that adjustment output magnitudes of the second regulation circuit can be impressed as reference or set values or adjustment magnitudes upon the first regulation circuits.

Abstract: A rolling mill system for the continuous rolling of metal strip or strand into a strip of predetermined thickness and straightness is disclosed. The system includes a frame in which two metal working rolls are mounted in such a way that both the distance or nip between the rolls and the tilt of one roll with respect to the other may be regulated by two gap adjusting devices mounted in the roll frame on opposite sides of the centerline of the metal strip. At least one of the gap adjusting devices is operated responsive to a signal representing a measurement of the straightness of the strip product. The gap adjusting devices are hydraulic assemblies wherein each piston is affixed to a piston rod and each piston rod is affixed at its opposite end to a chock block in which the movable roll is carried. A position indicating rod which constitutes part of a position transducer is affixed to the opposite face of each piston to allow for monitoring of the actual distance between the two rolls at each end thereof.

Abstract: The invention contemplates a prestressed rolling mill incorporating a system of hydraulically operated load-transfer blocks, wherein the blocks are of unitary construction and bodily interposed between vertically opposed regions of upper and lower back-up roll chocks, at the respective inlet and exit sides of each axial end of the mill. Each load-transfer block is inherently self-adapting (at each of a plurality of force-application regions) to such small locally different deformations in the mill frame as result from the block's modulating contribution to net prestressing force; further, each load-transfer block includes its own hydraulic-control system with minimum-displacement actuators whereby a fast time constant of hydraulic response is achieved.

Abstract: A method for peening a portion of the inside of a small diameter heat exchanger tube by inserting a rotating shaft having a peening strip affixed thereto, orbiting and reciprocating the shaft as it rotates, and maintaining this operation for a predetermined length of time to relieve residual tensile stresses in a portion of a tube installed in a heat exchanger.

Abstract: A tube is bent a desired angle by locating it over a mandrel, clamping the tube between a clamp die and bend die, rotating the clamp and bend dies through the desired angle, where extraction of the mandrel from the tube is initiated before rotation of the dies is completed.

Abstract: Calibration of sensors of the type used for the cutaneous determination of blood oxygen and carbon dioxide levels is facilitated by providing separate sensor units, alternatively and removably connectable to a calibration device and to the measuring devices with which they are used for such determinations. The sensor units contain, in addition to a sensor electrode, a data memory in which is stored calibration data generated when the sensor unit is connected to the calibration device. The calibration device can provide a plurality of calibration stations, each capable of supplying a standard gas to a connected sensor and, in response to signals from the sensor exposed to the standard gas, generating data signals representing the calibration of the sensor, which signals are transmitted to the data memory of the sensor unit. Upon connection of the sensor unit to the measuring device, the calibration data from the data memory of the sensor unit are used as a calibration base for measurements by the sensor.

Abstract: According to the invention, fluid is adapted to flow through a piston and cylinder disposed in the housing of a meter prover. The cylinder is telescopingly received within the piston. The fluid is permitted to flow into the piston and cylinder through an upstream inlet and leave through exit ports in the cylinder. A poppet valve is provided for closing the exit ports whereupon the piston becomes a fluid barrier and is adapted to move in synchrony with the fluid flow from the upstream fluid inlet. A single detector is provided which is activated at the start of the proving run and at the end of the proving run. A rack is mounted on the piston for turning a gear. The gear rotates a disc having a plurality of markings indicating the incremental displacement of the piston. A photopulser transmits a pulse to a counter for each marking detected upon rotation of the disc. Sufficient piston displacement is permitted to generate a minimum of 10,000 pulses.

Abstract: A prover detector comprising a barrel having a longitudinal bore formed therethrough to receive a proximity switch mounted in one end thereof and a piston mounted in the other end thereof to extend from the barrel bore into the prover. The proximity switch is of the type that is responsive to the proximity of an unmagnetized, ferromagnetic mass near the end thereof disposed within the barrel bore for closing a set of contacts in the proximity switch and the piston has a cylindrically symmetric portion at the end thereof nearest the proximity switch, such portion centered on an axis of movement of the piston relative to the proximity switch defined by the barrel bore, so that the position of the piston for which the contacts in the proximity switch close depends only upon the distance between the proximity switch and the piston.

Abstract: In an externally ignited internal combustion engine with a knocking sensor which comprises a membrane to absorb the vibrations of the engine housing during knocking of the internal combustion engine, cooperating with a vibration absorber, whereby the membrane is formed by a thin walled location of the engine housing or by an opening in the wall of the engine housing which is closed by a membrane plate. The knocking sensor can be mounted at an easily accessible location and it is also assured that the resonance characteristic of all internal combustion engines of a series are the same at the location scanned by the knocking sensor.

Abstract: Method and apparatus for determination of the concentration of a component in a solution, such as ethyl alcohol in gasohol, acetic acid in hexane-acetic acid solution, or the like. Such determination is made with ease and accuracy based on a rate of pressure change caused in a closed container due to mass transfer occurring between two liquids through porous material.

Abstract: A method and apparatus are disclosed for monitoring the condition of the stirring block and solid plug therein as incorporated in the normal refractory brick lining of a molten metal ladle to provide a structure through which gas can be introduced into the molten metal, the method utilizes heat sensors and/or Hall Effect transducers embedded in the stirring block and/or solid plug therein in connection with apparatus providing a warning of critical wear and/or erosion in the gas stirring devices by the molten metal in the ladle. An appropriately shaped stirring block provides for the positioning of some of the normal refractory brick lining of the ladle partially thereover so as to eliminate loosening or cracking of the stirring block and the undesirable escaping of molten metal from the ladle.

Abstract: This invention sets forth a wind tracking device particularly useful on sailing vessels for determining the best sailing direction relative to the wind. The reference card is provided with color panels which cooperate with lines on the dome to indicate best direction. Further, the card has circular lines about the axis which cooperate with a dot on the axis of the dome to indicate a 360.degree. level condition around a horizontal plane.

Abstract: The invention provides ultrasonic apparatus 64 for measuring the amplitude of oscillation of a fluid. The apparatus 64 combines an ultrasonic flowmeter 60, 62, 65 which gives an indication of velocity of the fluid, with an integrating circuit 74. The integration is carried out over successive half-cycles of the oscillation, and may be arranged to give an average value of the amplitude.

Abstract: An internal gate rotary vane fluid meter which has markedly improved performance as a result of precise control over the geometry and dimensions of the rotating elements and the fluid flow path. In particular, the vanes are dimensioned to each have a length no greater than 1.5 times their width.

Abstract: A dew sensor of direct current type and resistance-lowering type with increasing humidity for quick and sharp detection of dewing is provided, which comprises a pair of counterposed electrodes, humidity-sensitive layer of insulating porous metal oxide with a porosity of 20 to 60% provided on and between the counterposed electrodes, and an organic polymer coating layer having a thickness of 0.05 to 2 .mu.m provided on the humidity-sensitive layer.