JP2656213B2 - Absorption liquid pump of absorption refrigeration system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an absorption liquid pump for returning an absorption liquid to a regenerator in an absorption refrigeration system.

[0002]

2. Description of the Related Art In an absorption refrigeration system, a low-concentration absorbing solution such as an aqueous solution of lithium bromide is heated and boiled by a regenerator to form a solution (refrigerant) and a high-concentration absorbing solution (aqueous lithium aqueous solution of high concentration). Are separated. The refrigerant is liquefied in a condenser provided with a cooling coil and supplied to the evaporator, and takes heat of evaporation from the evaporation coil disposed in the evaporator. The evaporated refrigerant is
Absorbed by the high-concentration absorbing liquid sprayed on the cooling coil of the absorber. The absorbing liquid having a low concentration after absorbing the refrigerant is returned to the regenerator by the absorbing liquid pump. In the heating operation, the flow of the absorbing liquid is such that the absorbing liquid heated by the regenerator is supplied to the evaporator, and is returned from the evaporator to the regenerator by the absorbing liquid pump.

[0003]

Since the absorbing liquid is hot and corrosive, a casing made of a corrosion-resistant metal such as stainless steel is used for the liquid pump portion of the absorbing liquid pump. As a result, the heat of the absorbing liquid is transmitted to the motor that drives the pump, and the control circuit built into the motor is damaged by the heat, and the insulation of the drive coil of the motor part is deteriorated, resulting in durability problems. . An object of the present invention is to provide an absorbent pump having excellent durability by preventing the heat of the absorbent pump from being conducted to the motor, protecting the control circuit and the drive coil incorporated in the motor from high temperatures. is there.

[0004]

SUMMARY OF THE INVENTION The present invention provides a motor, a coupling case connected to one end of a housing of the motor, a liquid pump connected to the other end of the coupling case, and an output of the motor. An absorption liquid pump for an absorption refrigerating apparatus comprising a magnet attached to a shaft and a magnet attached to an impeller shaft of the liquid pump, and a magnet coupling disposed with a gap in the coupling case. The pump casing of the liquid pump is formed of a corrosion-resistant metal, and the coupling case is formed of an engineering plastic such as polyphenylene sulfide, polybutylene terephthalate, or polyamide, which is hardly thermally deformed even at 120 ° C. or more and has poor heat conduction. And

[0005]

According to the present invention, since the pump casing is made of a corrosion-resistant metal, in the absorption refrigeration apparatus requiring strict airtightness, outside air enters the absorption liquid flow path for a long time. And has excellent corrosion resistance and durability against a corrosive absorbent at a high temperature of about 120 ° C. flowing through a liquid pump. A large amount of heat transmitted through the pump casing due to good thermal conductivity, which is a drawback of the corrosion-resistant metal, is blocked by a resin-made coupling case having poor heat conduction, and is prevented from being transmitted to the motor housing. At this time, the coupling case is made of an engineering plastic, such as polyphenylene sulfide, polybutylene terephthalate, or polyamide, which hardly undergoes thermal deformation even at 120 ° C. or higher and has poor heat conduction, so that practically sufficient durability can be obtained. Further, since the magnet coupling has a gap for blocking heat conduction, heat transmitted to the motor rotor via the output shaft is also prevented. As a result, the motor is prevented from being overheated, and thus has excellent durability.

[0006]

FIG. 1 shows an absorption refrigeration system including a high temperature regenerator 100 and a low temperature regenerator 3. High temperature regenerator 100
Comprises a gas-liquid separation unit 2 having an airtight medium-concentration absorbent partition 22 above the absorbent boiling unit 1 for heating and boiling the low-concentration absorbent. The low-temperature regenerator 3 is provided on the outer periphery of the gas-liquid separation unit 2 and includes a ceiling 3B having a gap 3A.
An absorber 4 is provided on the outer periphery of the low-temperature regenerator 3.
An evaporator 5 is installed on the outer periphery of the, and a condenser 6 is mounted above the absorber 4.

[0007] The absorption liquid boiling section 1 has an absorption liquid heating tank 11 heated by a gas burner B.
A pumping pipe 12 projects vertically from the top of 1. The gas-liquid separation section 2 includes a refrigerant partition 21 and the medium-concentration absorbing liquid partition 22 arranged on the outer periphery of the refrigerant partition 21.
The absorber 4 has a vertically-shaped cylindrically wound cooling coil 41 disposed inside an annular airtight container 40 provided on the outer periphery of the low-temperature regenerator 3. A high-concentration absorbing solution spraying device 42 for spraying the concentration absorbing solution is mounted. The bottom of the absorber 4 and the absorbing liquid boiling section 1 are connected by an absorbing liquid supply passage L4 in which an absorbing liquid pump P is interposed. The condenser 6 has a cooling coil 61 disposed inside an annular airtight container 60.

The upper portion of the absorbing liquid boiling section 1 is provided with an ascending flow path L1.
(The pumping pipe 12) and supplies the boiling absorbing liquid (absorbing liquid having a medium concentration due to evaporation of the refrigerant vapor and the refrigerant) into the gas-liquid separation unit 2. The upper part of the low-temperature regenerator 3 serves as a gas-liquid separator 31.
And a gap 6A. The lower part of the condenser 6 and the refrigerant liquid dispersing tool 52 installed above the evaporator coil 51 of the evaporator 5 are communicated with each other by a refrigerant liquid supply passage L6 in which a solenoid valve V3 with an orifice is interposed. The bottom inside the refrigerant partitioning cylinder 21 communicates with the top or bottom (the top in the figure) of the low-temperature regenerator 3 through the medium-concentration absorption liquid supply passage L2. A high-temperature heat exchanger H2 and a solenoid valve V1 are mounted on the medium-concentration absorbent supply path L2. Refrigerant partition 21 and medium concentration absorbent partition 2
2 is a refrigerant liquid receiving portion 26, and the refrigerant flow path L
5 communicates with the condenser 6.

The high-concentration absorbent receiving section 36 of the low-temperature regenerator 3
Is connected to a high-concentration absorbent sprayer 42 by a high-concentration absorbent supply passage L3 provided with a low-temperature heat exchanger H1. The cooling coil 41 is connected to the cooling coil 61, and further connected to the cooling tower 43 via a circulation path L7.
The cooling coil 61 circulates in the order of the cooling tower 43. The absorption liquid is the absorption liquid boiling section 1 → gas-liquid separation section 2 → low temperature regenerator 3 →
It circulates in the order of absorber 4 → absorbent pump P → absorbent boiling section 1.

As shown in FIG. 2, the absorption liquid pump P includes a motor 7, a coupling case 8 fastened to a tip of a housing 71 of the motor 7, and a liquid pump fastened to a tip of the coupling case 8. 9 The motor 7 has an electromagnetic induction coil 7 on the inner wall of the housing 71.
2 and a rotor 73 is disposed in the coil 72. An output shaft 74 protrudes from the front end of the housing 71, and a control mechanism 75 including a control circuit is incorporated at the rear end of the housing 71. The coupling case 8 has a cylindrical shape, and is made of engineering plastic such as polyphenylene sulfide, polybutylene terephthalate, or polyamide, which is hardly thermally deformed even at 120 ° C. or more and has poor heat conduction.

The liquid pump 9 has a suction port 9 at the center on the tip side.
1, a pump casing 94 made of stainless steel provided with a discharge port 92 on the outer periphery and a magnet ring chamber 93 in a cylindrical partition wall A protruding into the coupling case 8 on the rear end side. A stainless steel impeller 95 is rotatably provided in the casing 94. The outer periphery of the rear end of a shaft 96 of the impeller 95 is integrated with the impeller 95 near the inner peripheral wall of the magnet ring chamber 93. The inside rotating magnet ring 81 is attached. An outer magnet ring 82 disposed so as to surround the outer periphery of the magnet ring chamber 93 is connected to the output shaft 74 of the motor, and rotates integrally with the output shaft 74.
Inner magnet ring 81 and outer magnet ring 82
Constitutes a magnetic coupling 80, and the impeller 95 is rotationally driven via the magnetic coupling 80 as the motor 7 rotates.

During use of the absorbent pump P, the absorbent at about 120 ° C. flows through the liquid pump 9 and the temperature of the pump casing 94 rises to the same extent. In the present invention, since the coupling case 8 is formed of a resin, the heat of the liquid pump 9 is transferred to the resin coupling case 8 having poor heat conduction.
And transmission to the housing 71 is suppressed. Further, since the magnet coupling 80 has the gap G that blocks heat conduction, heat transmitted to the rotor 73 via the output shaft 74 is also prevented. Accordingly, the motor 7 is prevented from being excessively heated, and the control mechanism 75 including the control circuit mounted on the rear end of the housing 71 is prevented from being exposed to a high temperature.
In the present invention, the motor housing 71 and the coupling case 8 may be integrally formed of resin.

Next, the operation of the absorption refrigeration system will be described. In this absorption refrigerator, a low-concentration absorbent (aqueous lithium bromide) containing a large amount of refrigerant (water) is supplied to a high-temperature regenerator 1
00, the refrigerant contained in the absorbing liquid is boiled, the refrigerant is partially separated, and the absorbing liquid having a medium concentration flows into the ascending flow path L1.
Gas-liquid separating unit 2A provided by the gas-liquid separating umbrella 2A
Accumulates in the medium concentration absorbent receiving portion 2B.

Since the inside of the gas-liquid separation section 2 is almost at atmospheric pressure and the inside of the low-temperature regenerator 3 is maintained at a low pressure of 70 mmHg, a medium-concentration absorbent is supplied through a supply passage L2 to a solenoid valve with an orifice. The top 32 of the low-temperature regenerator 3 via V1
Supplied to At this time, the medium-concentration absorbent is liquid-liquid heat-exchanged by the low-temperature low-concentration absorbent in the high-temperature heat exchanger H2 and cooled. A medium-concentration absorbing liquid partition 22 that separates the gas-liquid separating section 2 from the low-temperature regenerator 3 is a heat transfer wall for heating the absorbing liquid in the low-temperature regenerator 3 with the refrigerant vapor in the gas-liquid separating section 2. The refrigerant liquid generated by the condensation on the inner surface of the intermediate-concentration absorbing liquid partition 22 is caused to flow down to the refrigerant liquid receiving portion 26 between the intermediate-concentration absorbing liquid partition 22 and the refrigerant partition 21.

The medium-concentration absorbent in the low-temperature regenerator 3 entering from the top portion 32 is reheated by the heat of the gas-liquid separation unit 2 through the medium-concentration absorbent partition 22 and boils again, so that the low-temperature regenerator 3 The refrigerant evaporated in step 3 is completely separated and the high-concentration absorbing liquid receiving section 3
Run down to 6. As a result, the absorbing liquid having a high concentration is supplied to the absorbing liquid spraying device 42 above the absorber 4 via the supply path L3. At this time, the high-concentration absorbing liquid is cooled by being exchanged heat in the low-temperature heat exchanger H1 provided in the supply passage L3, and heats the low-concentration absorbing liquid in the supply passage L4. Further, the refrigerant vapor separated in the gas-liquid separation unit 31 is connected to the communication passage 3.
It enters the condenser 6 through A and 6A and is cooled and liquefied by the cooling coil 61.

The liquefied refrigerant in the condenser 6 is supplied to a supply passage L6.
Is supplied to the evaporator 5 while the flow rate is controlled by the solenoid valve V3 according to the required refrigerating capacity. 5m inside the evaporator 5
In a substantially vacuum state of about mHg, the refrigerant sprayed from the coolant sprayer 52 to the surface of the evaporating coil 51 evaporates and takes heat of evaporation from the evaporating coil 51. Thereby, the working fluid of the evaporating coil 51 is cooled, and the cooled working fluid flows to the indoor unit 53 of the air conditioner to perform cooling. Since the evaporated refrigerant is absorbed by the high-concentration absorbing liquid dropped from the absorbing liquid sprayer 42, the inside of the evaporator 5 (absorber 4) is maintained at a low pressure.

Since absorption heat is generated at the time of absorption, a cooling coil 41 is arranged in the absorber 4, the absorbed heat is absorbed by the cooling water in the cooling coil 41, and then discharged to the outside in the cooling tower 43. The absorption capacity is maintained. The low-concentration absorbing liquid that has absorbed the refrigerant is heated by the low-temperature heat exchanger H1 and the high-temperature heat exchanger H2 provided in the absorbing liquid supply path L4 by the absorbing liquid pump P and circulated to the high-temperature regenerator 100. . At this time, an electromagnetic proportional control valve V2 provided between the absorbent pump P and the high-temperature regenerator 100 adjusts the flow rate of the low-concentration absorbent to be returned according to the set operating conditions such as the required refrigerating capacity. Is done.

That is, in this absorption refrigeration apparatus, the refrigerant vapor generated from the absorption liquid in the high-temperature regenerator 100 is condensed on the inner surface of the medium-concentration absorption liquid partition 22 by heat exchange with the low-temperature regenerator 3, The refrigerant liquid to In addition, low temperature regenerator 3
Sends the refrigerant vapor generated from the absorbing liquid to the condenser 6. Then, in the condenser 6, the refrigerant vapor is condensed by the action of the cooling water in the cooling coil 61, and the refrigerant liquid sent from the condenser 6 to the evaporator 5 is evaporated by the action of the evaporator coil 51. The refrigerant vapor sent to 4 is absorbed by the absorbing liquid, the absorbed heat is taken out by the action of the cooling water in the cooling coil 41, and the cooling water is circulated with the cooling tower 43. As a result, the heat input from the air-conditioning indoor unit (cooling target) 53 is sent from the evaporator 5 to the absorber 4, is applied to the cooling water by the action of the cooling coil 41, and is discharged from the cooling tower 43 to the outside. You.

When the absorption refrigeration system is operated for heating, the cooling / heating switching solenoid valve V4 provided in the communication path L7 for connecting the medium-concentration absorption liquid receiving portion 2B in the refrigerant partition 21 and the evaporator 5 is operated. The valve is opened and the absorbent heated by the high-temperature regenerator 100 is supplied to the evaporator 5. The water in the evaporating coil 51 is heated by the high-temperature absorbing liquid, supplied to the indoor unit 53 of the air conditioner, and acts as a heating heat source. The absorbent in the evaporator 5 is circulated to the absorbent boiler 1 by the absorbent pump P via the absorbent supply path L4. At this time, the absorbing liquid heated to about 120 ° C. flows into the absorbing liquid pump P. However, similarly to the cooling operation, the heat insulation of the resin coupling case 8 causes the control circuit of the motor 7 and the trouble of the driving coil. Can be effectively prevented.

[Brief description of the drawings]

FIG. 1 is a conceptual diagram of an absorption refrigeration apparatus.

FIG. 2 is a sectional view of the absorbent pump according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 100 High temperature regenerator 1 Absorption liquid boiling part 2 Gas-liquid separation part 3 Low temperature regenerator 4 Absorber 5 Evaporator 6 Condenser 7 Motor 8 Coupling case 9 Liquid pump 80 Magnet coupling P Absorbing liquid pump

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Toru Fukuchi 4-1-2 Hirano-cho, Chuo-ku, Osaka-shi Inside Osaka Gas Co., Ltd. (72) Inventor Kaoru Kawamoto 4-1-2, Hirano-cho, Chuo-ku, Osaka-shi No. Osaka Gas Co., Ltd. (56) References JP-A-1-294990 (JP, A) JP-A-60-252200 (JP, A) JP-A-59-1880099 (JP, A) 10993 (JP, U)

Claims (1)

(57) [Claims] A motor; a coupling case connected to one end of a housing of the motor; a liquid pump connected to the other end of the coupling case; a magnet mounted on an output shaft of the motor; In an absorption liquid pump of an absorption refrigeration apparatus comprising a magnet attached to an impeller shaft of a liquid pump and a magnet coupling disposed with a gap in the coupling case, a pump casing of the liquid pump is provided. Made of corrosion resistant metal
And the coupling case is made of polyphenylene
Sulfide, polybutylene terephthalate, polyamide
Even at 120 ° C or higher, thermal deformation is unlikely to occur and heat conduction is poor.
An absorption liquid pump for an absorption refrigeration system, which is formed of engineering plastic .