2098 results about "Frost" patented technology

The invention is directed to an article with a liquid-impregnated surface, the surface having a matrix of features thereupon, spaced sufficiently close to stably contain a liquid therebetween or therewithin, and preferable also a thin film thereupon. The surface provides the article with advantageous non-wetting properties. Compared to previous non-wetting surfaces, which include a gas (e.g., air) entrained within surface textures, these liquid-impregnated surfaces are resistant to impalement and frost formation, and are therefore more robust.

The invention discloses a cleaning method and device for an indoor heat exchanger of an air conditioner. The cleaning method for the indoor heat exchanger of the air conditioner comprises the steps that 1, the air conditioner is controlled to operate in a refrigerating mode, an indoor draught fan is switched off, the surface of the indoor heat exchanger is frosted, and whether frosting is completed is judged; 2, after frosting is completed, the air conditioner is controlled to operate in a heating mode, the indoor draught fan is switched on, the frost on the surface of the indoor heat exchanger is converted into water, and whether defrosting is completed is judged; 3, after defrosting is completed, the temperature T of an inner tube of the indoor heat exchanger is controlled to be a first preset temperature TS1, the temperature TS1 of the inner tube of the indoor heat exchanger is kept for a first preset time tS1, and cleaning is completed. By the adoption of the cleaning method for the indoor heat exchanger of the air conditioner, cleaning of the indoor heat exchanger of the air conditioner can be achieved, no part is additionally arranged, cost is not increased, the high-temperature sterilizing function is achieved, and the comfort and health of a user are further improved.

The invention discloses an automatic cleaning treatment method and an automatic cleaning treatment system of an air-conditioning heat exchanger. The automatic cleaning treatment method comprises the following steps: after an air-conditioner is started, judging whether the starting condition of automatic cleaning treatment of the air-conditioning heat exchanger is met; if yes, starting the refrigerating mode of the air-conditioner to enable surface of the heat exchanger to frost, and judging whether frosting is finished; after the frosting is finished, controlling the refrigerating mode of the air-conditioner to turn off, starting the air supply mode, then, starting an indoor draught fan to enable frost on the surface of the indoor heat exchanger to melt to water, and judging whether defrosting is finished; and after the defrosting is finished, controlling the heating mode of the air-conditioner to start, drying the heat exchanger, and ending cleaning. According to the invention, the inner side heat exchanger frosts after the temperature is rapidly decreased and covers and wraps dust and germs during frosting, the dust and germs on the heat exchangers are rapidly discharged along with water flow of a large quantity of defrosting water generated during the defrosting process, and automatic cleaning is realized through redrying treatment.

The invention relates to an injection device (100, 200, 300) which is capable of resisting proximal movements of a piston rod (107, 207, 307) relative to a housing (102, 202, 302), when the piston rod (107, 207, 307) is subjected to proximally directed forces below a threshold magnitude, and of allowing reversible proximal movements of the piston rod (107, 207, 307) relative to the housing (102, 202, 302), when the piston rod (107, 207, 307) is subjected to proximally directed forces of or above the threshold magnitude.

The invention discloses a cleaning control method for an indoor heat exchanger of an air conditioner. The cleaning control method includes the steps that when the air conditioner gets into the automatic cleaning mode, the refrigeration mode is started; evaporating temperature is reduced to enable water in air to be condensed into frost or thin ice on the indoor heat exchanger; after the air conditioner continuously runs in the refrigeration mode for set refrigeration time, the running mode of the air conditioner is switched to the heating mode from the refrigeration mode so that the frost or the thin ice on the heat exchanger can be thawed to clean the heat exchanger. The invention further discloses the air conditioner. By means of the cleaning control method and the air conditioner, automatic cleaning of the indoor heat exchanger of the air conditioner can be achieved, and therefore it can be avoided that the heat exchange efficiency of the heat exchanger is reduced.

A refrigerated display case having a transparent insulating glazing unit for displaying cold or frozen products. The glazing unit has an antifrosting absorbent layer that inhibits the formation of visible condensation or frost.

A defogging device for a surveillance camera has a heating element, a circuit board and a power cord. The heating element is mounted over the lens of the surveillance camera. The circuit board compares ambient temperature to a preset temperature, activates the heating element and has a power input terminal, a power output terminal and a temperature sensor. The temperature sensor is mounted between the power input terminal and the power output terminal and senses ambient temperature. When the ambient temperature is above the preset temperature, the circuit board activates the heating element. The power cord is connected to the circuit board and the heating element and transmits power to the heating element from the circuit board. By activating the heating element during periods of cold ambient temperature, the defogging device removes fog and frost from or keeps fog and frost from forming on the lens of the surveillance camera.

An apparatus to refrigerate the cargo space of delivery vehicles. It provides an environmentally friendly alternative to conventional mechanical a/c and refrigeration units. Cooling is provided by controlled evaporation of a liquefied gas such as CO.sub.2 or nitrogen. Defrost and heating requirements, if needed, are provided by hot engine coolant or by electric heaters powered from the vehicle electrical system. Airflow for the evaporator and for circulation in the temperature controlled space is provided by a blower which is mechanically or electrically driven from vehicle power. This invention can also be applied to multi-temperature control applications. The apparatus is compact and is particularly suited for small inner city delivery vehicles. FIG. 1: The sketch shows an inner city delivery truck for which this invention is most suitable. Refrigerated goods are placed in roller cages that are designed to maximize cargo hauled by use of roller cages that extend to within 2 inches of the ceiling. The evaporator section of this invention is mounted at or near the front wall of the truck and is separated from the cargo by a vertical bulkhead. The conditioned air is delivered at the bottom of the truck to avoid top freeze of perishable cargo that is in close proximity to the ceiling. FIG. 2: This shows the piping schematic and is similar to the invention described in U.S. Application Serial No. 60/238,929 (the '929 application) incorporated herein by reference. FIG. 2 shows the engine coolant coil located ahead of the CO.sub.2 coil in the direction of airflow. This prevents the coldest air from coming in contact with the engine coolant--in the cooling mode the air leaving the CO.sub.2 coil can be as low as -50.degree. F. for frozen load applications and this may cause the engine coolant to start freezing. Arrangements must be made to circulate air between the two coils in defrost mode. One means to accomplish this is to place a damper at the outlet of the evaporator section and run the fans. The damper would be closed during defrost. Another method is to place the engine coolant coil on the discharge side of the CO.sub.2 coil and use a cut-out switch if the engine coolant temperature drops below a predetermined value. In this arrangement there is no need for the damper arrangement as the heat will rise to melt any frost on the CO.sub.2 coil. If electric heat is used for defrost and heating freezing of the engine coolant is not a concern and the heaters can be fastened to the discharge side of the CO.sub.2 coil. An electric stand-by mode can be provided to power the system for cooling, heating and defrost when the vehicle is parked with the engine off. A plug-in electrical cable can provide the power needed for the controls, the fans and for heating and defrost. The figure shows the electric heaters attached on the discharge side of the CO.sub.2 coil. Operation: Detailed description is in the '929 application except for the following: The evaporator section is designed for vertical installation to maximize cargo space. Air is discharged at the bottom but may be a conventional top discharge if needed for specific applications. Conventional methods can be used to provide defrost and heating. If engine coolant is used for a heat source, it is preferable to thermally isolate the CO.sub.2 coil from the engine coolant coil to avoid freezing the coolant. The evaporator blower may be located on the inlet side of the coils rather than as shown in the figures. Unique Features: 1. Absence of a conventional condensing section on the exterior of the vehicle makes this an ideal refrigeration unit for small inner city delivery vehicles. Many of the truck cabs are now almost full height (same as the truck body) and there is limited space for the condensing section. 2. Cold plates can be used and still maximize cargo cube. However, this invention has 30-40% less weight than comparable "cold plate" systems. 3. Other features are described in the '929 application.]

The invention provides an intelligent defrosting method for a frequency-conversion air conditioner. Whether the air conditioner enters a defrosting program or not is judged according to a series of comprehensive factors such as the ranges of the indoor coil temperature, the indoor environment temperature, the outdoor coil temperature and the outdoor environment temperature, differences of the corresponding temperatures and heating running duration and cumulative time, the defrosting exit condition is determined according to the factors such as the defrosting duration and the range of the outer machine coil temperature, and the technical problems that in the prior art, the defrosting condition is simply set, and consequently the phenomena that defrosting is wrongly conducted when frost does not exist, defrosting is frequently conducted when frost is thin, and defrosting is not conducted when frost is thick possibly happen, and the heating effect of the air conditioner is affected can be solved. According to the intelligent defrosting method for the frequency-conversion air conditioner, the intelligent degree of defrosting of the air conditioner can be improved, the effects that defrosting is conducted when frost exists, defrosting is not conducted when frost does not exist, defrosting begins when frosting reaches a certain degree, and defrosting of an outdoor unit is thorough and timely can be improved, the accurate defrosting efficiency of the air conditioner can be effectively improved, and the heating performance of the air conditioner is improved.

An energy recovery ventilator and method for monitoring and maintaining an environmental condition inside a structure such as a house, building, or dwelling is provided. The ventilator may include a housing having mating halves of a molded polymeric material, first and second chambers disposed within the housing to convey separate first and second streams of air, a heat exchanger configured to intersect the first and second chambers, a first fan to circulate the first air stream through the first chamber, a second fan to circulate the second air stream through the second chamber, and a fan motor driving the first and second fans. The ventilator may also be configured to prevent frost build-up in or on the energy ventilator, to provide efficient cooling, and maintain one or more desired environmental conditions.

The invention relates to the field of refrigeration defrosting of refrigerators, in particular to a defrosting system and a refrigerator with the defrosting system. The defrosting system comprises an evaporator body and a precooling evaporator, wherein the precooling evaporator is arranged at the bottom of the evaporator body and is used for cooling and dehumidifying high-temperature high-humidity air returning from a return air inlet. One end of the precooling evaporator is communicated with the return air inlet. The other end of the precooling evaporator is communicated with the evaporator body. According to the defrosting system, the precooling evaporator is arranged at the bottom of the evaporator body, after the high-temperature high-humidity air returning from the return air inlet is cooled and dehumidified through the precooling evaporator, cooling and heat exchange are conducted on the cooled and dehumidified air through the evaporator body, and therefore part of frost condenses on the precooling evaporator; in this way, the amount of frost on the evaporator body is obviously reduced, frost is even, and the heat exchange efficiency of the evaporator body is effectively improved.

A device capable of extracting heat of phase transformation of compressed steam for radiative heat transfer adopts the structure that each group of heat pipe component is composed of a heat pipe and a sleeve; each heat pipe comprises a heating section and a condensation section, one end of the condensation section is sealed, the other end of the condensation section is communicated with one end of the heating section, and an end cover is arranged at the other end of the heating section; one end of each sleeve is welded at the joint of the heating section and the condensation section of the corresponding heat pipe, and the other end is welded together with an air-in communicating pipe; a hydrops baffle, as well as a liquid discharge pipe interface, is arranged in each air-in communicating pipe; and one end of each air-in communicating pipe is connected with the corresponding end cover, and an interface connected with a compressed steam delivery pipe is arranged at the other end. In theinvention, water or other liquid transportation can be avoided, so a huge heat exchange system and a delivery pipe net for heating liquid are prevented, the power consumption during the liquid transportation is also avoided, waterway frost cracking can also be prevented, and the maintenance cost is reduced.

The invention discloses a defrosting control method for an air conditioner. The defrosting control method includes the steps that when the air conditioner enters a defrosting mode, outdoor environment temperature and outdoor environment humidity are obtained; whether the outdoor environment temperature and the outdoor environment humidity meet preset conditions is judged; if yes, an outdoor fan is controlled to rotate reversely according to the pipe temperature and defrosting time of an outdoor heat exchanger so that defrosting can be performed on an enclosure net cover of the outdoor heat exchanger. According to the control method, residual frost on the enclosure net cover of the outdoor heat exchanger can be effectively cleared away. The invention further discloses a defrosting control device for the air conditioner.

The energy-free refrigeration door of the present application provides a way to control condensation when the door of a refrigeration unit is opened by providing thermal insulation to the door with glass panels which have a low emissivity coating. The door includes a door frame housing and an insulating glass unit comprising inner, middle and outer sheets of glass. A first sealant assembly disposed around the periphery of the inner and middle sheets of glass forms a first chamber between the inner and middle sheets of glass. A second sealant assembly disposed around the periphery of the middle and outer sheets of glass forms a second chamber between the middle and outer sheets of glass. A gas, such as krypton, air, or argon is held in the first and second chambers. The outer sheet of glass and inner sheet of glass each have an unexposed surface that faces the middle sheet of glass. A low emissivity coating is disposed on the unexposed surfaces of the inner and outer sheets of glass so that the glass door as a whole avoids formation of condensation on the outer surface of the outer sheet of the glass door, without the application of electricity to heat the door, while also providing the desired evaporation rate of condensation from the inner side of the inner sheet of the glass door. An anti-fog or anti-frost coating is included on a surface of one of the sheets of glass.

The invention is directed to an article with a liquid-impregnated surface, the surface having a matrix of features thereupon, spaced sufficiently close to stably contain a liquid therebetween or therewithin, and preferable also a thin film thereupon. The surface provides the article with advantageous non-wetting properties. Compared to previous non-wetting surfaces, which include a gas (e.g., air) entrained within surface textures, these liquid-impregnated surfaces are resistant to impalement and frost formation, and are therefore more robust.

The invention relates to the field of laminated glass, particularly a laminated glass with high heat reflectivity and electric heating function applicable to the field of vehicles or construction, more particularly an automobile windshield glass installed on a vehicle. The electrically-heatable low-emissivity coated laminated glass comprises two glass substrates, a middle polymer sandwiched between the two glass substrates, low-emissivity film and a bus, wherein the low-emissivity film is arranged on at least one glass substrate surface in contact with the middle polymer; the bus is distributed on the low-emissivity film; and the bus is a pressure-sensitive adhesive or anisotropic conductive adhesive. According to the electrically-heatable low-emissivity coated laminated glass provided by the invention, the ACF (anisotropic conductive film) or PSA (pressure-sensitive adhesive) is used as the bus in combination with the low-emissivity film to heat the laminated glass, thereby removing frost and melting ice; and thus, compared with the adoption of other buses, the invention simplifies the production technique, is convenient to operate, lowers the material cost and enhances the production efficiency and process yield.

A construction form system for forming concrete walls for use as above grade walls, foundations, frost walls, exterior envelopes, and the like, is disclosed. The system includes a plurality of pairs of opposing vertical forming panels spaced from each other to define a forming cavity disposed to receive a hardenable material. Each pair of opposing forming panels comprises an inner panel forming part of an inner wall and an outer panel forming part of an outer wall. The system also includes an outer rail positioned between each adjacent pair of outer forming panels and an inner rail positioned between each adjacent pair of inner forming panels. The inner forming panels comprise support panels configured to be selectively addable and removable from between each adjacent pair of inner rails prior to and subsequent to a pouring of the hardenable material into the cavity.

The invention discloses a washing method of an air conditioner. The washing method comprises the steps: S1, dewing is conducted, specifically, refrigeration is conducted to form condensate water for primary washing; S2, frosting is conducted, specifically, refrigeration is conducted to form a frost layer; S3, heating is conducted, specifically, heating is conducted to defrost to washing the surface of a heat exchanger, and sterilization is conducted; and S4, ventilating is conducted, so that the heat exchanger is quickly dried and cooled. The air conditioner comprises a control device, and operations of the rotating speed of a fan and the operating frequency of a compressor of the steps are preset in the control device, wherein the preset operation in the step S3 is that the mapping relation between the pipe temperature T of the heat exchanger and the frequency of the compressor and the mapping relation between the environment temperature and the rotating speed of the fan cooperate tocontrol the pipe temperature of the heat exchanger. According to the washing method, on the one hand, two-step cleaning is achieved, and sterilization is conducted; on the other hand, a system of theair conditioner is utilized to the largest extent; and secondly, through setting of the heating stage, the problems that under the high-temperature working condition, the operating frequency is too high, the air speed is too low, the pipe temperature rises too quickly, when frequency decreasing is triggered, the pressure is too high, and compressor driving protection occurs are avoided.

The invention discloses throat nourishing health-care type electronic cigarette liquid, which is used for producing electronic cigarettes, can meet the requirement of smoking addiction, contributes to smoke absorbing and throat nourishing, protects the throat of a human body and maintains health. The electronic cigarette liquid mainly comprises the following components in percentage by weight: 2 to 6 percent of plant cigarette substituting agent, 48 to 55 percent of propylene glycol, 25 to 35 percent of pure water, 4 to 6 percent of tobacco flavor, 0.25 to 1.2 percent of stabilizer, 4 to 9 percent of thickening agent and 3 to 6 percent of Chinese medicinal component, wherein the Chinese medicinal component comprises 3 to 5 types of watermelon frost, peppermint oil, menthol, blumea aromatria, eucalyptus oil and star anise oil according to an equal proportion. The electronic cigarette liquid has the effects of promoting secretion and nourishing throat, clearing sound and eliminating phlegm, and reducing swelling and relieving pain during the enjoyment of smoking, can prevent and treat throat sore, hoarseness, canker sore, stomatitis and gum swelling and pain, and has good curative effect on throat diseases such as dryness, swelling and pain of the throat accompanied by the hoarseness.

Sill seal and termite shield (SSTS) devices are disclosed. The SSTS devices for residential housing are shown for poured concrete, masonry block, and frost protected shallow foundations. The polymeric foam pad of the SSTS device seals the rough surface atop the foundation wall. For the termite shield function, the SSTS devices use a metallic web—either of foil or of an impenetrable screen—or a nonmetallic web—either of plastic sheet or of impenetrable scrim. The termite shield or barrier layer is shown as adjacent to a weatherproofing membrane or as an interior layer of an polymeric laminate weatherproofing membrane. Hot melt adhesives attach the foam pad to the weatherproofing membrane and, where applicable, the barrier layer to the weatherproofing membrane. Pressure-activated, hot melt adhesives attach the SSTS device to the sill plate. A release sheet is applied forming a peel-and-stick device.

The invention discloses a multifunctional road soil roadbed freezing and thawing circulating test device. During a freezing and thawing circulating test, six samples are placed among six top plate heat exchangers and six bottom plate heat exchangers of a constant temperature system; the six top plate heat exchangers and the six bottom plate heat exchangers are respectively connected in parallel with a refrigeration circulating machine set; a moisture replenishment system is connected with the bottoms of six roadbed soil samples; a temperature sensor and a soil moisture sensor of a test systemare respectively buried in the six roadbed soil samples of the samples; a displacement sensor of the test system is in contact with the top of the top plate heat exchanger of a temperature control system; and the temperature sensor, the displacement sensor and the soil moisture sensor are connected with an acquisition channel of a data acquisition instrument of a data acquisition system. The multifunctional road soil roadbed freezing and thawing circulating test device has the advantages of simple structure, convenient use, high test precision and reliable result, can better complete the parallel test measurement of the engineering design parameters of roadbed soil modulus of resilience, CBR (Constants Bit Rate) intensity, and the like in a seasonal frost region under a least favorable state, which cannot be achieved by the traditional devices, and can directly provide necessary design parameters for engineering design.

An ultrasonic method for removing and/or avoiding unwanted build-up on structures is provided, wherein the term build-up refers to, but is not limited to, ice, dirt, mud, or other wanted debris or contamination. Deicing or anti-icing structures of interest can include, but are not limited to, helicopter rotor blades, other helicopter blade components, fixed wing aircraft components, windshields in aircraft, automobiles, and other vehicles, ship hulls or other ship components, heat exchangers and other tubing where frost or ice could form, air-conditioning components, head lamp and other light coverings, bridge structures and components, and any structure where anti-icing or deicing would be beneficial. One or more ultrasonic actuators permanently embedded or coupled to the structure may be used accomplish the removal. The technique presented herein could also be utilized for non-destructive evaluation and structural health monitoring applications.

The invention discloses a defrosting control method for an intelligent air cooling heat pump, belonging to the field of refrigeration and air conditioning. The method comprises the following steps: when an air conditioner is started for heating, a controller detects the outdoor ambient temperature and the temperature of a coiled tube of an outdoor heat exchanger; when the temperature of the coiled tube of the outdoor heat exchanger is lower than the preset frosting temperature of the coiled tube, the coiled tube is judged to be frosted, and the difference between the outdoor ambient temperature and the temperature of the coiled tube of the outdoor heat exchanger at the moment is recorded as the initial frosting temperature difference of the coiled tube; and then the difference between the outdoor ambient temperature and the temperature of the coiled tube of the outdoor heat exchanger is dynamically recorded and judged, and when the difference between the difference and the initial frosting temperature difference of the coiled tube recorded previously is greater than the temperature difference of a preset allowable frosting thickness, and the operation time of a compressor is longer than the preset unstable operation time of the compressor, the air conditioner enters a defrosting mode. The invention has the beneficial effects that: defrosting is carried out only when frost is formed, the defrosting frequency of the compressor and time for defrosting every time are reduced, an unnecessary defrosting period is reduced, and the effects of saving electricity and prolonging the service life of equipment are achieved.

The invention provides a heat tower heat pump, mainly consisting of a cold/heat source absorption device closed heat tower and a low-temperature heat tower elevating device low-temperature heat source heat pump. The invention can be used as an efficient water evaporation cooling device in summer and an efficient broadband frost-free air source heat pump in winter, realizing cooling in summer and heating in winter, capable of supplying hot water for households; thereby the invention can be used for the three purposes.

The invention belongs to the technical field of air conditioners, and aims at solving the problems that when an existing air conditioner conducts defrosting, the optimal defrosting mode cannot be selected according to the outside temperature condition and the thickness of a frost layer on an air conditioner outdoor unit. Accordingly, the invention provides an air conditioner and a defrosting control method thereof. The method comprises the following steps that the outdoor environment temperature and the first preset temperature are compared; if the outdoor environment temperature is larger than or equal to the first preset temperature, the air conditioner is controlled for bypass defrosting; if the outdoor environment temperature is smaller than the first preset temperature, whether the thickness of the frost layer on the air conditioner outdoor unit meets the preset condition or not is judged; if the thickness of the frost layer meets the preset condition, the air conditioner is controlled for bypass defrosting; and if the thickness of the frost layer does not meet the preset condition, the air conditioner is controlled for refrigerating defrosting. By means of the air conditioner and the defrosting control method thereof, the optimal defrosting mode can be adopted under the situation that the outdoor environment temperature is high or low or the frost layer on the air conditioner outdoor unit is relatively thick or thin, the comfort of the indoor environment is guaranteed, and the air conditioner heating effect is improved.

The invention discloses an air conditioner cleaning device and cleaning method, and belongs to the technical field of air conditioner cleaning. An air conditioner comprises a heat exchanger and a water receiving disk. The cleaning device comprises a water storage which communicates with the water receiving disk, atomizers and an actuator, wherein the water storage is used for storing condensed water in the water receiving disk, the atomizers are located above the heat exchanger, and the actuator is connected with the water storage and the atomizers, and used for conveying the condensed water in the water storage to the atomizers. The air conditioner cleaning device can store part of the condensed water in the original water receiving disk, when the air conditioner needs frost condensation for cleaning, the moisture content inside an indoor unit is increased with condensed water, then, the thickness of the ice layer of frost condensation of the air conditioner is increased, and therefore, the cleaning effect of the air conditioner is improved; and meanwhile, condensed water can be recycled, and the product ideas of economization and environmental protection are met.

An automated storage and retrieval system stores containers, typically containing biological or chemical samples, at ultra-low temperatures, i.e., from about −50° C. to about −90° C., preferably about −80° C. under normal operating conditions. Dry gas air flows are used to reduce moisture and the consequential frost within the freezer compartment. A custom insulated door is provided with an access module and a tube picking compartment as well as servo motors for controlling a robot within the ultra-low temperature freezer compartment. The robot automatically places sample storage containers in stationary storage racks within the freezer compartment. Magnetic couplings are used to transmit mechanical power from outside of the freezer compartment to the robot inside of the freezer compartment. The robot has a simplified mechanical configuration. The custom door can be readily attached to standard freezer bodies.

The invention discloses an air conditioner. The air conditioner comprises an outdoor unit, an indoor unit, a four-way valve and a compressor which are connected through connecting pipes, and further comprises a first temperature sensor, a second temperature sensor and a controller. The first temperature sensor is arranged on the air inlet side of a heat exchanger of the outdoor unit. The second temperature sensor is arranged on the air outlet side of the heat exchanger of the outdoor unit. The input end of the controller is electrically connected with the first temperature sensor and the second temperature sensor. The output end of the controller is electrically connected with the four-way valve. When the time spent by the air conditioner on heating circulation is longer than a preset first time threshold value and the time duration during which the temperature difference between the air inlet temperature and the air outlet temperature is smaller than or equal to a preset temperature threshold value is larger than a second preset time threshold value, the controller controls valve openings of the four-way valve to be switched, and the air conditioner is switched into defrosting circulation from heating circulation. The invention further discloses a defrosting control method of the air conditioner. By means of the air conditioner and the defrosting control method of the air conditioner, defrosting can be effectively conducted in time, and the situation that defrosting is conducted when no frost exists is avoided.

A protective arrangement for preventing parts of the body from being trapped between at least two mutually relatively moveable parts including at least one strip which is associated with at least one part. There are provided in the strip at least two mutually spaced conductive elements extending in the longitudinal direction of the strip. An electronic sensor system serves to produce an output signal for a capacitance that is adapted to vary as a result of external influences. Due to the fact that at least one first conductive element sends out a signal which is received by at least one second conductive element due to the capacitive effect of the first conductive element and that the second conductive element is at substantially the same electrical potential as the first conductive element and likewise sends out the received signal, there is provided a capacitive crush protection arrangement which does not react to splashes of water or the formation of dew or frost.

The invention relates to a hyper-branched polycarboxylate high-efficiency water reducing agent and a preparation method thereof. The water reducing agent is prepared by polymerizing one of tert-butyl acrylate and methyl tert-butyl acrylate with sodium methyl-acryl sulfonate and allyl polyethenoxy ether to form a copolymer main chain, and then performing condensation polymerization on one of acrylic acid and methacrylic acid with ethylene diamine to form a hyper-branched polyamide structure which is grafted to two ends of the main chain. The preparation method comprises the following steps: (1) preparing the sodium methyl-acryl sulfonate into solution with DMF, and heating the solution in a nitrogen atmosphere; (2) dissolving the other two monomers and an initiating agent into the DMF to prepare mixed solution, and dripping the mixed solution into the step (1) to react for 1 to 20 hours; (3) adding a condensating agent CDI after the reaction and performing condensation reaction by using N-methyl morpholine as an organic base, the ethylene diamine and the acrylic acid as the monomers and the DMF as a solvent; and (4) performing vacuum distillation to remove the residual monomers and the solvent, and refluxing for 2 to 5 hours by using methylene chloride solution of trifluoroacetic acid to obtain the water reducing agent. The hyper-branched polycarboxylate water reducing agent has the advantages of low admixture, high water reducing rate, small slump loss, good compatibility with cement, no corrosivity to steel bars, strong frost resistance and the like.