Abstract: A variable air volume heating, ventilation and air conditioning (HVAC) system controller with adaptive control architecture adjusts control parameters to provide for increased direct expansion coil air flow and reduced compressor cycling. The supply air temperature set point is adjusted as a function of the return air temperature and compressor cycling is time limited.

Abstract: A method for controlling a heating of a heater in a heating-type humidifier in which both a heating amount and a heating ON/OFF period is controlled on the basis of a present room temperature, is disclosed. A sensed present humidity is compared with an objective humidity which is set by a user. When the present humidity is greater than or equal to the objective humidity, whether or not water exists in a water tank of the humidifier is determined. When the water does not exist in the water tank, an alarm is generated. When the water exists, a humidifying operation stops. When the present humidity is less than the objective humidity, the humidifying operation is executed while increasing both a heating amount and a heating ON period of the heater in proportion to the present room temperature. As a result, the arrival times at the states of objective humidity are shortened.

Abstract: The invention shows an improvement in the lubrication of bearings and shaft seals of screw compressors for refrigerants with oils soluble in refrigerants. A typical application results, for example, for ammonia with polyalkylene glycol soluble therein. Due to the fact that a partial oil flow is taken out of the oil flow returned to the screw compressor at an intermediate pressure prior to a pressure reduction to nearly suction pressure of the compressor and conveyed via a vapor separation container, substantial proportions of the dissolved refrigerant can be fed in at an intermediate pressure connection on the compression path of the screw compressor. Correspondingly more advantageous are the lubrication properties of the remaining partial oil flow at the lubrication connection, and the disadvantages of pressure collapse or foam conveyance at an oil pump are absent, since no oil pump is required with a suitable intermediate pressure.

Abstract: In an automobile air-conditioner comprising a compressor with variable discharge capacity for compressing a refrigerant, an outlet temperature sensor for sensing an outlet temperature at an outlet of at least one of a heat sink and a radiator, a room temperature sensor for sensing a room temperature inside the automobile, an outside air temperature sensor for sensing an outside air temperature outside the automobile, and a room temperature setting unit for setting the room temperature to a desired temperature, a first arithmetic operating unit carries out an arithmetic operation according to at least the room temperature, the outside air temperature, and the desired temperature, to obtain a target temperature. A second arithmetic operating unit predicts the rotation speed of the compressor with a predetermined feed-forward arithmetic expression to obtain a predicted rotation speed.

Abstract: An Integrated controller for a commercial vehicle air conditioning system according to the present invention includes a central control unit in communication with a high-pressure switch or sensor, a low-pressure switch or sensor, and an evaporator thermostat. The central control unit includes outputs that control the air conditioning system compressor and fan according to the conditions detected by the high pressure switcher sensor, the low pressure switch or sensor, and the evaporator thermostat.

Abstract: An improvement for a refrigeration system that includes a refrigerant circuit and a compressor with condenser assembly. The improvement is a pre-cooling device connected to the output of the condenser and includes an inlet and two outlets. The inlet is connected to a serpentine at one end and the other end is connected to one of the outlets. The other outlet is connected to the device housing above the bottom concavity where the liquid refrigerant is collected. The serpentine comes in at least partial contact with the refrigerant and in that manner pre-cooling the refrigerant going through the serpentine.

Abstract: A highly reliable air conditioning system which can be operated by commonly available compressors and produce a higher energy utilization efficiency in desiccant assisted air conditioning process while offering an economical cost of purchase as well as operation is disclosed. The air conditioning system is made by combining a desiccant assisted air conditioner with a plurality of vapor compression refrigeration circulation units, each unit having a compressor, an evaporator and a condenser. The circulation units are arranged so that the evaporators and the condensers are disposed in a last-come-first manner in relation to an order between a process air passage and a regeneration air passage.

Abstract: A geothermal heating and/or cooling system includes one or more of a plurality of features that enhance the efficiency of the system. Preferably, the system includes a subterranean heat exchanger having tubes disposed against a conductive sheet. The system also preferably includes a reservoir vessel for holding a supply of heat transfer fluid in a liquid phase. Also, the system preferably includes heat exchange means for exchanging heat between the heat transfer fluid and the outdoor air. In addition, the system preferably has an automatically adjusting cooling expansion valve controlled by a sensor disposed to detect the pressure or temperature of heat transfer fluid exiting an indoor air handler in a cooling mode, the system also preferably has an automatically adjusting heating expansion valve controlled by a sensor that is preferably located so as to detect the temperature or pressure of heat transfer fluid flowing from the subterranean heat exchanger to a gas compressor.

Abstract: A highly efficient motor driver circuit of an electronic controller for linear cryogenic coolers operates directly from a variable power supply, such as a battery, without the need for the voltage regulator control circuit of the prior art. Elimination of the prior art voltage regulator ensures a higher efficiency motor driver circuit of the electronic controller. Both open-loop and closed-loop controllers electronically control the motor driver circuit. The open-loop controller protects against temperature sensor failure, and will limit maximum motor power as a function of system ambient temperature. The closed-loop controller regulates the temperature of the cold finger accurately to a preset value, using feedback from a temperature sensor along with a novel pulse-width modulation concept for modifying motor drive waveforms.

Abstract: Conventional vapor-compression refrigeration systems modified for greater efficiencies by installation of a liquid refrigerant level sensor in the drain line after the condenser, the sensor activating a valve in the high pressure vapor line in communication with the refrigerant receiver or reservoir, and the drain line being trapped to prevent vapor in the reservoir from backing up into the condenser.

Abstract: A humidifier for use with a hot air furnace has an upper and lower housing removably connected to one another. The upper housing has a heating element and sensor, water refill inlet, and a control circuit connected to the heat sensor and inlet. The lower housing contains a water vessel and a water level sensor secured the lower housing to receive the water vessel. The water sensor registers the minimum and maximum water weight and is connected to the control circuit. A bacteria resistant, semi-flexible removable liner fits within the vessel for the removal of built up mineral residue. Preferably the water sensor is an elliptical beam load cell with an open center surrounded by a rim and a pair of tab ends opposite one another. At least one bridge is machined within the rim to increase sensitivity. A strain gage registers strain changes and an electronic connector transfers the changes to the control circuit where they are converted to the current weight.

Abstract: An air conditioner is made to follow up a change in load in an efficient manner by utilizing the fact that the components of a three-component mixed medium serving as a substitute for Freon have different boiling points. The mixed medium, which consists of R-32, R-125 and R-134a, is sealed within the circuit of the air conditioner, and a supercooled heat exchanger and liquid-gas tank are interposed between an outdoor heat exchanger and an expansion valve. The liquid-gas tank is connected to an accumulator via a liquid injection valve.

Abstract: The invention entails the use of a positive displacement pump (4) magnetically coupled to an drive motor (42) located in a conduit arrangement (60) this is parallel to the liquid line of the refrigeration system as in FIG. 5. This parallel conduit arrangement also includes a pressure regulating valve that will regulate the amount of pressure added to the liquid line by the parallel pump and piping arrangement. In addition, a check valve (47) is located in the liquid line to maintain the pressure differential added to the liquid line. This parallel piping arrangement (60) is desirable in order to allow a constant, pre-determined pressure to be added to the liquid line regardless of variations in flow rate of the liquid refrigerant. In addition, the parallel piping arrangement allows the system to operate without liquid line obstruction in the event of pump failure.

Abstract: A commercial refrigeration network including refrigeration system units constructed and arranged for placement in strategic proximity to corresponding product cooling zones within the shopping arena of a food store, each refrigeration unit having a condensing unit rack configured to accommodate the maximum refrigeration loads of its associated zone with an optimum floor space footprint in the shopping arena, and the condensing unit rack including a plurality of multiplexed compressors, condenser and associated high side and low side refrigerant delivery and suction conduits operatively connected to evaporators for cooling the corresponding zone, and the network also including another cooling source remote from said modular refrigeration units and constructed and arranged for circulating a fluid coolant in heat exchange relationship with the condenser to obtain optimum condensing and efficiency of said evaporators in cooling the corresponding zone.

Abstract: A temperature program pattern PP for desired change of surface temperature TC1 of a work 11 with time is set by a temperature setter 31. Work temperature-difference .DELTA.t.sub.pv between the surface temperature TC1 and inside temperature TC2 of the work 11 is determined by a difference detector 34. Set value of the above temperature-difference .DELTA.t.sub.sp is given by a difference setter 35 in the form of a difference pattern DP of its change with the above surface temperature TC1. For each actual surface temperature TC1, the work temperature-difference .DELTA.t.sub.pv is compared against its set value on the difference pattern DP by a comparator 36. A slope operator 37 responds to the output from the comparator 36 and modifies slope of the temperature program pattern PP so as to cause the work temperature-difference .DELTA.t.sub.pv to follow the difference pattern DP.

Abstract: A device for monitoring and modulating the admission of fresh air into a building. The device comprises a housing; a sensor associated with the housing and operable to measure airflow through the housing; and a damper including at least two damper blades. Each damper blade includes a shaft rotatably attached to the housing at least at a first shaft end. The shaft is located on the surface of the damper blade so as to divide the surface into first and second substantially equal areas.

Abstract: A refrigerant circulating system using non-azeothropic mixture as refrigerant, which comprises: a main refrigerant circuit connected by a compressor, a fore-way valve, an outdoor heat-exchanger, a first throttling device, a plurality of indoor heat-exchangers, and a low-pressure receiver; a bypass circuit diverging from the discharge portion of the compressor, and extending through a composition detecting heat-exchanger and a second throttling device to a low-pressure portion; an outdoor fun attendant of the outdoor heat-exchanger; first temperature detector to detect a refrigerant temperature at the upstream of the second throttling device; second temperature detector to detect a refrigerant temperature at the downstream of the second throttling device; first pressure detector to detect a pressure at the downstream of the second throttling device; third temperature detector to detect temperature in the main circuit between the first throttling device and the indoor heat-exchanger; forth temperature detector

Abstract: A controller for a climate control system has a relative humidity sensor as well as a dry-bulb temperature sensor within the enclosure. The humidity value is used in conjunction with the dry-bulb temperature to generate an apparent temperature error signal which is a function of both the dry-bulb temperature and the relative humidity values. This permits robust control of both enclosure temperature and enclosure moisture content without abnormal cycling of the climate control system. Instead of using a sensor which directly measures the apparent temperature, the apparent temperature can be synthesized from the relative humidity and dry-bulb temperature within the enclosure. Alternately, the sensed and set point apparent temperature values can be synthesized from any two thermodynamic properties of the moist air within the enclosure.

Abstract: In a heating mode, the fluid in the air conditioning circuit flows in a bypass branch avoiding the condenser. The evaporator then receives the fluid in the gaseous state and acts as a heat exchanger for dissipating the heat produced in the compressor. The heat dissipated by the evaporator may be employed to heat the cabin when that produced by the drive motor of the vehicle is insufficient. In addition, special configurations of the circuit enable the mass of fluid flowing in the heating loop to be increased or reduced with a view to regulating the calorific power produced.

Abstract: An actuator has a drive gear set to interact with a driven lug to rotate the lug and whatever the lug is fixed to. The actuator must be separately anchored to interact with the lug. The drive gear and the lug have cams that are spaced apart, so that when the lug is fixed to an object which is off its linear axis, there is play in the gear relationship to allow rotation to function. In a system with an actuator, such as a thermostat, temperature can be controlled by turning a valve on a radiator on and off. End of travel is sensed by a current surge stopping the acutation. The system is ideal to operate radiators in a steam heat system.