Hitachi, Ltd.

Michihiko Aizawa

Tomihisa Ohuchi

Akira Nishiguchi

Daisuke Hisajima

Heihatiro Midorikawa

Seiichiro Sakaguchi

Takashi Nakao

Katsumi Mabuchi

Takashi Honda

Tomoko Kikuchi

Masahiko Ito

Yasuo Koseki

Kyoji Kohno

Shigeo Sugimoto

Hiroaki Yoda

Masahiko Itoh

Yasumasa Furutani

Ryoko Sakiyama

Katsuya Ebara

Yoshifumi Kunugi

Toshio Sawa

Kenji Yokose

Yoshitaka Nishino

Yasuo Fujitani

Iwao Harada

Tamio Shimizu

Kazutoshi Itoh

Toshifumi Kunugi

Takao Naruse

Yasuo Uraki

Kouji Imura

Nobutaka Miyoshi

An absorption refrigerator includes a high temperature regenerator for heating a water solution including a halogen compound to generate steam. An oxide film having thickness of 0.02&#x2013;5.0 &#x3bc;m, one of the colors blue, purple and gray, or a hydroxyl group is formed on a surface of at least one of the high temperature regenerators and the heat exchanger.

Absorption refrigerator and production method thereof

An absorption refrigerator includes a high temperature regenerator for heating a water solution including a halogen compound to generate steam. An oxide film having thickness of 0.02-5.0 &mgr;m, one of the colors blue, purple and gray, or a hydroxyl group is formed on a surface of at least one of the high temperature regenerators and the heat exchanger.

There is disclosed an absorption refrigerating machine in which evaporators as well as absorbers are arranged in a two-stage manner. A refrigerant, heated by a regenerator, is condensed by a condenser, and then is fed to a first evaporator. The refrigerant, produced in the first evaporator, is absorbed by a first absorber, formed integrally with the first evaporator, and is formed into an intermediate solution, and then is fed to a second absorber. The second absorber comprises a spray absorber which obviates the need for providing a heat-transfer pipe therein. The condensed refrigerant is supplied to a second evaporator, formed integrally with the second absorber, from a refrigerant tank formed at a lower portion of the condenser or at a lower portion of the first evaporator. The refrigerant, fed to the second evaporator, is absorbed by the solution sprayed in a supercooled condition in the second absorber, thereby producing a dilute solution. Part of the dilute solution, raised in temperature by absorbing the refrigerant, is returned to the first evaporator, and exchanges heat with liquid refrigerant, condensed in the condenser, to be cooled. The cooled dilute solution is again sprayed in the second absorber. The dilute solution in the second absorber is kept in a supercooled condition, and therefore the chilled water or brine, flowing through a heat-transfer pipe, provided in the second evaporator, can be kept to a low temperature under 0&deg; C.

Absorption refrigerating machine

There is disclosed an absorption refrigerating machine in which evaporators as well as absorbers are arranged in a two-stage manner. A refrigerant, heated by a regenerator, is condensed by a condenser, and then is fed to a first evaporator. The refrigerant, produced in the first evaporator, is absorbed by a first absorber, formed integrally with the first evaporator, and is formed into an intermediate solution, and then is fed to a second absorber. The second absorber comprises a spray absorber which obviates the need for providing a heat-transfer pipe therein. The condensed refrigerant is supplied to a second evaporator, formed integrally with the second absorber, from a refrigerant tank formed at a lower portion of the condenser or at a lower portion of the first evaporator. The refrigerant, fed to the second evaporator, is absorbed by the solution sprayed in a supercooled condition in the second absorber, thereby producing a dilute solution. Part of the dilute solution, raised in temperature by absorbing the refrigerant, is returned to the first evaporator, and exchanges heat with liquid refrigerant, condensed in the condenser, to be cooled. The cooled dilute solution is again sprayed in the second absorber. The dilute solution in the second absorber is kept in a supercooled condition, and therefore the chilled water or brine, flowing through a heat-transfer pipe, provided in the second evaporator, can be kept to a low temperature under 0.degree. C.

An absorption refrigerator uses water as a refrigerant and a halogen compound as an absorption solution, and is characterized in that an oxide film of thickness of 0.02-5.0 .mu.m is formed on a surface of at least one of a heat exchanger and a high temperature regenerator. And a production method of the absorption refrigerator is characterized by oxidizing a surface of at least one of a heat exchanger and a high temperature regenerator at a temperature of 200-800.degree. C., and adjusting a heating temperature and a heating retaining time so that a value of parameter (P), obtained according to P=T (5+log t) is 3.5-6.0.times.10.sup.3, wherein T represents heating temperature (.degree.K), and t heating retaining time (minute).

An absorption refrigerator uses water as a refrigerant and a halogen compound as an absorption solution, and is characterized in that an oxide film of thickness of 0.02-5.0 .mu.m is formed on a surface of at least one of a heat exchanger and a high temperature regenerator. And a production method of the absorption refrigerator is characterized by oxidizing a surface of at least one of a heat exchanger and a high temperature regenerator at a temperature of 200.degree.-800.degree. C., and adjusting a heating temperature and a heating retaining time so that a value of parameter(P), obtained according to P=T (5+log t) is 3.5-6.0.times.10.sup.3, wherein T represents heating temperature (.degree.K), and t heating retaining time (minute).

The capacity control range of an interior unit of a multiple type absorption air conditioning system is increased, and turning on and off of cooling/heating and switch over between the cooling and heating can be readily and safely performed. The capacity control range is increased by reserving a liquid refrigerant in an absorption cool/warm water unit. An interior unit is connected to the absorption cool/warm water unit by a communication device. The operation of the cool/warm water unit caused by turning on and off the system and switch over between cooling and heating are automatically controlled by an operation control device. Consequently, the operation is simplified, and safety is improved.

Multiple type absorption air conditioning system

An absorption refrigerator is characterized by an absorber which has a tube bank of heat-conductive tubes in the absorber, a vapor flow passage between the tube bank and a side wall of the absorber which is opposite to and separated from the tube bank in a radial direction of the heat-conductive tubes by a distance equal to or larger than a maximum pitch of the heat-conductive tubes, at least a baffle plate disposed in the vapor flow passage, and a gas extraction port disposed outside the tube bank. A further arrangement is characterized by an absorber having a tube bank in the absorber, a vapor flow passage between the tube bank and a side wall of the absorber, and a gas extraction port disposed around a central portion of the tube bank.

Absorption refrigerator

The capacity control range of an interior unit of a multiple type absorption air conditioning system is enlarged, and turning on and off of cooling/heating and switch over between the cooling and heating can be readily and safely performed. The capacity control range is increased by reserving a liquid refrigerant in an absorption cool/warm water unit. An interior unit is connected to the absorption cool/warm water unit by a communication device. The operation of the cool/warm water unit caused by turning on and off the system and switch over between cooling and heating are automatically controlled by an operation control device. Consequently, the operation is simplified, and safety is improved.

A high temperature regenerator of an absorption type hot and cold water generator and an absorption type hot and cold water generator capable of preventing corrosion from occurring by preventing local overheating at the heat transfer surface of the high temperature regenerator and capable of being miniaturized. The high temperature regenerator includes an outer case, an inner case, a plurality of solution pipes, a burner, a solution flow-in pipe, and a gas/liquid separation plate. The inner case is inside the outer case, and a solution is kept between the cases, with the inner case being submerged within this solution. The burner is mounted on the side of the outer case in such a way that heat can be supplied through the inner case, with the inside of the inner case serving as a combustion chamber. A plurality of solution pipes, through which the upper and lower portions of the inner case are connected, are disposed downstream of the combustion chamber, and the inside of each of the solution pipes is filled with the solution. The horizontal cross section of each of the solution pipes is elliptical, and two or more of the solution pipes are disposed so that the straight line portions in the elliptical shape become parallel to each other. The sections between the solution pipes serve as a combustion gas passage.

High temperature regenerator of an absorption type hot and cold water

An individual air conditioning system with an absorption chiller heater having a controllable capacity, with thermal input to a burner of a high temperature regenerator being controlled by on-off control or the like even if the load is low. The temperature of cooling water is controlled in accordance with a concentration of refrigerant in an absorber, so that the refrigerating capacity of the absorption chiller heater can be freely varied from 0% to 100% without the refrigerant being frozen.

Control method and apparatus of absorption chiller heater

In an absorption air-conditioning system, in order to immediately stop indoor air-conditions by a stop signal of the indoor air-conditioners and improve characteristics for activating the system , such as, by effecting re-activation at a relatively short time interval after stopping the operation of the system, when the last one of the operating indoor air-conditioners is stopped, a stop signal is sent to a control device from a controller for the indoor air-conditioner, and in response to this signal, the control device effects the control of stopping a burner, a cooling medium circulating pump, a cooling water pump and a cold/hot water, pump. A solution circulating pump, however, continues operating and the solution, while kept at a high concentration, is circulated through an absorber, a high-temperature regenerator and a low-temperature regenerator. During this time, an indicated value of a temperature sensor gradually decreases, and when this value reaches a predetermined temperature, the control device switches a control valve from its open condition to its closed condition and another control valve from its closed condition to its open condition, and also activates the cooling medium circulating pump again to feed a cooling medium to a solution reservoir at a lower portion of the absorber, thereby diluting the solution.

Absorption air-conditioning system

An absorption heat pump apparatus is so formed that solution which has absorbed coolant vapor in absorber to increase in temperature, liquid coolant into which coolant vapor heat been condensed in a condenser, and coolant which has decreased in temperature through flash evaporation of coolant vapor in an evaporator are delivered directly to heat exchangers so as to exchange heat with the outdoor air, respectively. This arrangement makes the use of cold water and cooling water as well as equipment therefor and maintenance thereof unnecessary.

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Ushiku, Japan

Michihiko Aizawa