JP3148662B2 - 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 refrigeration system in which an absorption cycle is formed by using an aqueous solution having a high corrosivity such as lithium bromide as an absorption liquid, and an absorption liquid pump for circulating the absorption liquid in the absorption cycle. In particular, the present invention relates to an absorption liquid pump of an absorption refrigeration apparatus having a relatively small refrigeration capacity for use in ordinary households.

[0002]

2. Description of the Related Art In an absorption refrigeration system, a regenerator for heating an absorption liquid containing a refrigerant to separate refrigerant vapor from the absorption liquid,
A condenser for cooling and condensing the refrigerant vapor separated by the regenerator, an evaporator for evaporating the refrigerant condensed in the condenser under a low pressure, and an evaporating liquid for evaporating the refrigerant vapor in the evaporator to an absorbing liquid supplied from the regenerator. An absorber to be absorbed and an absorbent pump for returning the absorbent from the absorber to the regenerator are connected by several pipes to form an absorption cycle in which high airtightness with respect to the atmosphere is ensured.

In the above configuration, for example, when the regenerator is a double effect type comprising a high temperature regenerator and a low temperature regenerator, the high temperature regenerator heated by a burner or the like is covered with a refrigerant recovery tank, and A low-temperature regenerator is formed on the outside,
The medium-concentration absorbing liquid from which the refrigerant has been separated by the high-temperature regenerator is heated again by the heat of the high-temperature regenerator in the low-temperature regenerator, and is separated into refrigerant vapor and the high-concentration absorbing liquid. The refrigerant recovery tank for recovering the refrigerant vapor separated by the high-temperature regenerator communicates with the condenser by a refrigerant flow path having an orifice for giving a pressure difference between the refrigerant and the condenser. The absorbent storage part of the high-temperature regenerator in which the separated medium-concentration absorbent is stored communicates with the low-temperature regenerator through an absorbent flow path having an orifice that similarly applies a pressure difference to the low-temperature regenerator. I have.

In such an absorption cycle, the low-concentration absorbent is heated by a burner or the like in a regenerator while the absorbent pump is operated, and is boiled to separate the high-concentration absorbent and the refrigerant vapor to form a high-concentration absorbent. The liquid is sent to an absorber, while the refrigerant vapor is sent to a condenser where it is cooled and turned into a refrigerant liquid and sent to an evaporator. When the high-concentration absorbing liquid is sprayed on the surface of the absorbing coil in the absorber, while the refrigerant liquid is sprayed on the evaporating coil in the evaporator, on the evaporating coil surface, the refrigerant liquid evaporates from cold and hot water passing through the evaporating coil. The heat is removed and evaporated to be supplied to the absorber, where the high-concentration absorbing liquid absorbs the refrigerant and lowers the concentration. The absorbent in the absorber is returned to the regenerator by the absorbent pump.

[0005] As described above, the regenerator (high-temperature regenerator) heated by a burner or the like has the highest pressure in the absorption cycle. In order to feed the absorbent from the absorber into the high-pressure regenerator, A large discharge pressure is required for the absorbent pump. For this reason, in a conventional absorption refrigeration system for business use, a Century Hugal pump or a cascade pump is used as an absorption liquid pump, and the casing of these pumps is formed by cutting a cast product formed by cutting the shape of an impeller chamber. Have been.

In order to ensure airtightness between the inside of the pump in the absorption cycle requiring high airtightness and the outside on the atmosphere side, for example, a connecting portion between the absorption liquid pump and various pipes is provided with O. A rubber packing such as a ring is used. Although such rubber packing may deteriorate due to long-term use and deteriorate airtightness, it is common for maintenance-type absorption refrigeration equipment to perform maintenance work on equipment at predetermined intervals. Since the rubber packing is replaced during maintenance work, airtightness can be ensured for a long time.

[0007]

As described above, in the prior art, absorption refrigeration systems have been used mainly for business use and most of them have a large refrigeration capacity. When the refrigeration system is used for ordinary households, the refrigeration capacity does not need to be as large as that for commercial use. Therefore, in order to reduce the refrigeration capacity,
What is necessary is just to make the flow rate of the absorption liquid circulated in the absorption cycle significantly smaller than that of an absorption refrigeration system for business use, and to reduce the size of the pump itself.

However, even if the flow rate of the absorbing solution is reduced, the change in entropy is not different from that in the case of business use. Therefore, a higher precision is required for the shape of the impeller chamber of the pump casing than in the case of business use. However, if the accuracy is increased, it is troublesome and expensive, and the weight of the entire device including the pump is increased and the burden of the installation work is increased.

In addition, in the case of business use, since the rubber packing is replaced in the maintenance work, the absorption cycle and the airtightness between the outside and the outside can be ensured for a long period of time. If it becomes necessary, the operating cost increases. Therefore, it is desired that the inside and the outside of the pump casing have an airtight structure that requires no maintenance work for a long period of time.

[0010] The present invention provides a small absorption refrigeration apparatus,
It is an object of the present invention to provide an absorbent refrigeration pump for an absorption refrigeration apparatus which is lightweight and can secure a sufficient discharge pressure, can secure airtightness over a long period of time, and can be easily used for home use.

[0011]

According to a first aspect of the present invention, there is provided a regenerator for heating an absorbing liquid containing a refrigerant to separate the refrigerant vapor from the absorbing liquid, and regenerating the refrigerant vapor separated by the regenerator. A condenser for cooling and condensing, an evaporator for evaporating the refrigerant condensed in the condenser under a low pressure, and an absorber for absorbing the refrigerant vapor evaporated in the evaporator into an absorbent supplied from the regenerator. In an absorption refrigeration apparatus in which an absorption cycle is formed, an absorption pump for returning an absorption liquid from the absorber to the regenerator, wherein a casing of the absorption pump is made of resin for forming an impeller chamber for accommodating an impeller. The technical means is a double-structured casing comprising a casing and a sheet metal casing for enclosing the resin casing and ensuring airtightness in the absorption cycle.

[0012] With the above configuration, in the first aspect of the present invention,
In the absorption cycle, the casing of the absorbing liquid pump which requires a high discharge pressure and requires airtightness to the outside is constituted by a double-structure casing in which a resin casing is disposed inside a sheet metal casing. Since the impeller chamber for accommodating the impeller rotating in the absorption liquid pump is formed by a resin casing, complicated shapes such as dimensions correlated with the impeller can be formed with high precision in detail, such as cutting. It is possible without complicated work. In addition, since the molding is made of resin, unnecessary waste portions are not generated, and the thickness can be easily reduced, so that the weight can be reduced. On the other hand, since the outside of the resin casing is formed by the sheet metal casing, the molding is easily performed by press working, and by joining by welding, it is easy to secure the airtightness with the outside. In addition, airtightness can be ensured for a long period of time without performing maintenance work. Also,
The double-structured casing is inexpensive because it is made of a casing made of a resin casing and a sheet metal casing formed by a manufacturing method suitable for mass production. Therefore, the use of the double-structure casing of the present invention facilitates mass production, is inexpensive, has good performance, and can be used for a long period of time. It becomes easier.

According to a second aspect of the present invention, in the double-structure casing according to the first aspect, the resin casing and the sheet metal casing are brought into local contact at a plurality of locations to form the resin casing and the sheet metal casing. The technical means is that a plurality of protrusions for providing an interval of a predetermined size or more on the contact surface side are provided on the resin casing or the sheet metal casing. In an absorption refrigerating apparatus, for example, an absorption cycle is formed using an aqueous solution having a high corrosiveness such as lithium bromide as an absorbent, and an absorbent pump is used to circulate the aqueous solution. Therefore, the inside of the absorbent pump is filled with a highly corrosive aqueous solution.

When the sheet metal casing outside the double-structure casing is made of, for example, stainless steel, a metal or other foreign matter is present on the surface of the stainless steel to cause a substance involved in corrosion (here, odor). Movement of a highly corrosive aqueous solution such as lithium chloride)
If the solution inside and outside the gap is not replaced, crevice corrosion is likely to occur. In the double-structure casing, since the resin casing is disposed inside the sheet metal casing, if the sheet metal casing and the resin casing are in close contact with each other, an aqueous solution is interposed between the sheet metal casing and the resin casing. Is easy to stay. When the corrosive substance in the retained aqueous solution is fixed to the surface of stainless steel, crevice corrosion proceeds in the sheet metal casing.

For this reason, in the second aspect, the resin casing and the sheet metal casing are locally brought into contact with each other by the projections, and the other portions are formed with an interval of a predetermined size or more. The predetermined size is such that the aqueous solution can be easily moved by the pressure generated internally when the impeller rotates. As described above, when the aqueous solution moves between the resin casing and the sheet metal casing and the corrosive substance is replaced, crevice corrosion does not progress in stainless steel or the like. As described above, in claim 2,
Since the resin casing and the sheet metal casing are brought into local contact with a plurality of protrusions, and an interval is provided for facilitating the replacement of the aqueous solution between the resin casing and the sheet metal casing, the movement of the aqueous solution becomes easy, Crevice corrosion does not progress, for example, when stainless steel is used.

According to a third aspect of the present invention, in the second aspect, the inflow port of the absorbent pump is provided at the interval formed by the projections between the resin casing and the sheet metal casing of the double-structure casing. The technical means is that a seal member for blocking the communication with the discharge port is mounted. Accordingly, even if the discharge pressure generated on the discharge portion side of the resin casing due to the rotation of the impeller in the resin casing is applied to the space formed by the projection between the resin casing and the sheet metal casing, the absorbing liquid Since the communication between the inlet and the outlet of the pump is blocked by the seal member, a short circuit does not occur due to the pressure of the discharge portion side of the resin casing reaching the inflow portion side of the resin casing. All pressure on the discharge side of the casing is applied to the discharge port of the sheet metal casing. Therefore, even if an interval is formed between the resin casing and the sheet metal casing by the projection, the discharge capacity of the absorbent pump is not reduced.

[0017]

FIG. 1 shows an air conditioner using an absorbent pump of an absorption refrigeration system according to the present invention. The air conditioner includes an absorption refrigeration system 100 as an outdoor unit and an indoor unit R.
U, and the absorption refrigeration system 100 is
01 and a cooling tower (cooling tower) CT. The air conditioner is controlled by a control device (not shown). The refrigerator main body 101 forms an absorption cycle of a refrigerant and an aqueous solution of lithium bromide as an absorbing liquid, and includes a high-temperature regenerator 1 provided with a gas burner B as a heating source below, and an outside of the high-temperature regenerator 1. A low temperature regenerator 2 disposed so as to cover the low temperature regenerator 2, an absorber 3 and an evaporator 4 double disposed toward the outer periphery of the low temperature regenerator 2, and a low temperature regenerator. A condenser 5 arranged on the outer periphery of the vessel 2 and above the absorber 3 is connected by several passages.

The high-temperature regenerator 1 is provided above the heating tank 11 heated by the gas burner B with the medium-concentration absorbent separating cylinder 1.
2, a vertical cylindrical airtight refrigerant recovery tank 10 is provided so as to cover the outer periphery of the medium-concentration absorbing liquid separation tube 12 from above. Thus, in the high-temperature regenerator 1, the low-concentration absorbing liquid contained in the heating tank 11 is heated by the gas burner B, and water as a refrigerant in the low-concentration absorbing liquid is evaporated to form refrigerant vapor (water vapor).
As a result, the intermediate-concentration absorbing liquid is separated to the outside of the medium-concentration absorbing liquid separation tube 12, the medium-concentration absorbing liquid concentrated by evaporation of the refrigerant vapor is left in the storage portion 12 a inside the medium-concentration absorption liquid separating tube 12, and the separated refrigerant vapor is collected by the refrigerant. Collected in tank 10.

The low-temperature regenerator 2 is a vertical cylindrical low-temperature regenerator case 2 installed eccentrically on the outer periphery of the refrigerant recovery tank 10.
0, a refrigerant vapor outlet 21 is provided around the ceiling of the low-temperature regenerator case 20. Low temperature regenerator case 20
The top of the ceiling is connected to the storage part 12a of the medium-concentration absorption liquid separation cylinder 12 via the heat exchanger H by the medium-concentration absorption liquid flow path L1.

The storage section 12 is provided in the medium-concentration absorption liquid flow path L1.
an orifice (not shown) for restricting the flow rate of the medium concentration absorbing liquid flowing from
The medium-concentration absorbent is supplied into the low-temperature regenerator case 20 by a pressure difference from the medium-concentration absorbent separation cylinder 12. As a result, the low-temperature regenerator 2 reheats the medium-concentration absorbent supplied into the low-temperature regenerator case 20 using the outer wall of the refrigerant recovery tank 10 as a heat source.
The high-concentration absorbent is separated into refrigerant vapor and high-concentration absorbent in a gas-liquid separation unit 22 above the high-concentration absorbent.
Is stored at

A low-temperature regenerator case 20 has a vertical cylindrical airtight evaporating / absorbing case 30 disposed concentrically below the outer peripheral lower part thereof, and a condenser case 50 concentrically disposed above the outer peripheral upper part thereof. 10, the low-temperature regenerator case 20, and the evaporating / absorbing case 30 are integrally welded at each bottom plate to form a refrigerator main body 101. The low-temperature regenerator case 20 communicates with the inside of the condenser case 50 via the refrigerant vapor outlet 21 and the gap 5A.

The absorber 3 is provided with an absorption coil 31 which is wound in a vertical cylindrical shape inside an evaporating / absorbing case 30 and through which cooling water for exhaust heat flows, and above the absorption coil 31. A high-concentration absorbent spraying device 32 for dispersing the high-concentration absorbent to the absorption coil 31 is provided. The high-concentration absorbent sprayer 32 receives the high-concentration absorbent flowing from the high-concentration absorbent flow path L2 connected to the high-concentration absorbent reception section 23 of the low-temperature regenerator 2 via the heat exchanger H. Absorption coil 3
1 during the cooling operation in the absorption coil 31
The cooling water for exhaust heat cooled in the cooling tower CT circulates.

In the absorber 3, the high-concentration absorbent flowing from the high-concentration absorbent flow path L 2 due to the pressure difference from the low-temperature regenerator 2 is sprayed on the upper end of the absorption coil 31 by the high-concentration absorbent sprayer 32. It adheres to the surface of the absorption coil 31 to form a thin film, flows downward by the action of gravity, absorbs water vapor, and becomes a low-concentration absorbent. When absorbing the water vapor, heat is generated on the surface of the absorption coil 31, but is cooled by cooling water for exhaust heat circulating through the absorption coil 31. Note that the water vapor absorbed by the high-concentration absorbent is generated as refrigerant vapor in an evaporator 4 described later. The bottom 33 of the absorber 3 is connected to the bottom of the heating tank 11 via a low-concentration absorbent flow path L3 to which a heat exchanger H and an absorbent pump 210 are mounted. The low-concentration absorbing liquid in the tank is supplied into the heating tank 11.

The evaporator 4 has a vertical cylindrical wall provided with a communication port K provided on the outer periphery of an absorption coil 31 in an evaporator / absorber case 30. A cylindrical evaporator coil 41 is provided, and a refrigerant liquid sprayer 42 is mounted above the evaporator coil 41. The bottom portion 43 of the evaporator 4 is provided with a heating absorbing liquid flow path L having a heating electromagnetic valve 6.
4 communicates with the storage portion 12a of the medium-concentration absorption liquid separation cylinder 12.

In the evaporator 4, when the refrigerant liquid (water) is dropped on the evaporation coil 41 from the refrigerant liquid dispersing tool 42 during the cooling operation, the dropped refrigerant liquid is subjected to the surface tension of the evaporation coil 41.
Of the vaporizing coil 41 in the evaporating / absorbing case 30 at a low pressure (for example, 6.5 mmHg) while evaporating by evaporating and evaporating. The air-conditioning cold / hot water flowing in the coil 41 is cooled.

The condenser 5 is provided with a cooling coil 51 in which cooling water for exhaust heat cooled by the cooling tower CT circulates inside a condenser case 50. Condenser case 50
The bottom portion 14 of the refrigerant recovery tank 10 is provided by a refrigerant flow path L5 provided with an orifice (not shown) for restricting the flow rate of the refrigerant from the refrigerant recovery tank 10 to the condenser case 50.
And the refrigerant vapor outlet 21 and the gap 5A
And the refrigerant is supplied by a pressure difference (about 70 mmHg in the condenser case).

In the condenser 5, the refrigerant vapor supplied into the condenser case 50 is cooled by the cooling coil 51 and liquefied. The lower part of the condenser 5 and the refrigerant liquid disperser 42 disposed above the evaporator coil 41 of the evaporator 4 communicate with each other through a refrigerant liquid supply path L6. The liquefied refrigerant liquid passes through the refrigerant cooler 52 provided in the refrigerant liquid supply passage L6, and is supplied to the refrigerant liquid sprayer 4.
2 is supplied.

With the above structure, the absorbing liquid is supplied to the high-temperature regenerator 1 → the medium-concentration absorbing liquid channel L1 → the low-temperature regenerator 2 → the high-concentration absorbing liquid channel L2 → the absorber 3 → the absorbing liquid pump 210 → the low-concentration absorbing liquid. The liquid circulates in the order of the liquid flow path L3 and the high temperature regenerator 1. The refrigerant is a high-temperature regenerator 1 (refrigerant vapor) → refrigerant flow path L5 (refrigerant vapor) or a low-temperature regenerator (refrigerant vapor) → condenser 5 (refrigerant liquid) → refrigerant supply path L6 (refrigerant liquid) → refrigerant cooling Device 52 (refrigerant liquid) → refrigerant liquid disperser 42 (refrigerant liquid) → evaporator 4 (refrigerant vapor) → absorber 3 (absorbent liquid) → absorbent liquid pump 210 → low concentration absorbent liquid flow path L3 → high temperature regenerator 1 Circulate in order.

The above-described absorption coil 31 of the absorber 3 that exchanges heat with the absorption liquid and the cooling coil 51 of the condenser 5 are connected to form a continuous coil. The cooling water circulation path is formed by being connected to the CT. In this cooling water circuit, the absorption coil 3
A cooling water pump P2 for sending cooling water into the continuous coil is provided in a cooling water flow path 34 between the inlet of the cooling tower CT and the cooling tower CT.
The cooling water which passes through the continuous coil by the operation of the cooling water pump P2 absorbs the heat of absorption by the absorption coil 31 and the heat of condensation by the cooling coil 51, and becomes relatively high in temperature. Supplied to CT.

With the above configuration, during the cooling operation, the cooling water in the cooling tower CT is operated by the operation of the cooling water pump P2 so that the cooling tower CT → the cooling water pump P2 → the absorption coil 31 → the cooling coil 51 → the cooling tower CT. Circulate. In the cooling tower CT, self-cooling is performed in which the falling cooling water is partially evaporated into the atmosphere to cool the remaining cooling water.
An exhaust heat cycle is formed in which the heat is released into the atmosphere to lower the temperature. Note that the air from the blower S promotes the evaporation of water.

The indoor unit R is provided in the evaporator coil 41 of the evaporator 4.
U is connected by a cold / hot water flow path 45 formed of a rubber hose or the like.
5 is provided with a cold / hot water pump 260. The indoor unit RU is provided with a blower 46 that allows indoor air to pass through the air-conditioning heat exchanger 44 and blows out indoors again. With the above configuration, the cold / hot water whose temperature has become low in the evaporating coil 41 is circulated in the order of the evaporating coil 41 → the cold / hot water channel 45 → the air conditioning heat exchanger 44 → the cold / hot water channel 45 → the cold / hot water pump 260 → the evaporating coil 41. I do.

The absorbing liquid flow path L4 and the heating electromagnetic valve 6 are provided for a heating operation. During the heating operation, the heating electromagnetic valve 6 is opened and the absorbing liquid pump 210 is operated. As a result, the high-temperature medium-concentration absorbing liquid in the medium-concentration absorbing liquid separation tube 12 flows into the evaporator 4 from the bottom 43 of the evaporator 4 via the absorbing liquid flow path L4, and the evaporating coil 41
The cold and hot water in the inside is heated, and the heated cold and hot water in the evaporating coil 41 is supplied from the cold and hot water channel 45 to the air conditioning heat exchanger 44 by the operation of the cold and hot water pump 260, and becomes a heat source for heating. The medium concentration absorbent in the evaporator 4 enters the absorber 3 through the communication port K of the partition wall 40, and is returned to the heating tank 11 by the absorbent pump 210 via the low concentration absorbent flow path L3.

Next, in the refrigerator main body 101 of the absorption refrigeration apparatus 100 having the above configuration, the absorption liquid pump 21
The tandem pump 200 used as the zero and cold / hot water pump 260 will be described. FIG. 2 shows a cross section of the tandem pump 200 in the present embodiment. The tandem pump 200 has an absorption liquid pump 210 and a cold / hot water pump 260 arranged at both ends of a drive shaft 202 of a DC motor 201. Each of the pumps 210 and 260 is an end of the drive shaft 202 of the DC motor 201. This is a magnet pump driven by annular driving magnets 205 and 206 provided in couplings 203 and 204 fixed to the motor.

The absorbent pump 210 is formed by welding two sheet metal casings to ensure the airtight outer casing 22.
0, 230, and an inner casing 240 made of two resin casings that are arranged in combination inside the outer casings 220, 230 to form a high-precision impeller chamber;
A rotatable impeller 211 is housed in a double-structured casing composed of 250. As shown in FIG. 3, the lid-shaped outer casing 220
A disk-shaped stainless steel plate having a zero inflow port 221 formed at the center is pressed so as to form a plurality of steps toward the inflow port 221.

The other pot-like outer casing 230 is
As shown in FIG. 4, a stainless steel plate is pressed into a substantially pot-like shape.
A concave portion 231 for supporting one end of a shaft 212 for supporting the rotation of the shaft 11 is formed. A discharge port 232 of the absorbent pump 210 is formed on the peripheral wall of the pot-shaped outer casing 230, and a joining edge 233 for welding with the lid-shaped outer casing 220 is opened outward on the periphery. Is formed. 234 is a stud bolt used when assembling to the DC motor 201.

The dish-shaped inner casing 240 is disposed on the side of the lid-shaped outer casing 220, and has a substantially dish-like shape as shown in FIG. Dish-shaped inner casing 240
An inflow portion 241 for communicating the inside of the dish-shaped inner casing 240 with the inflow port 221 is formed at a central portion of the substantially dish-shaped portion, and the center of the inflow portion 241 is for supporting the other end of the shaft 212. The shaft receiving portion 242 is connected to the inflow portion 241.
Are provided continuously with three legs 243 extending from the periphery. Around the dish-shaped inner casing 240,
An outer edge wall 244 that separates the inner side and the outer side of the dish-shaped inner casing 240 is formed.
In order to obtain a large discharge pressure during one rotation, the outer edge wall 24
A spiral groove 245 having a spiral shape whose depth with respect to 4 is increased.

Further, on the outer side of the outer edge wall 244, there is formed a predetermined distance between the pot-shaped outer casing 230 and a portion other than the local contact with the pot-shaped outer casing 230. A plurality of ribs 246 (corresponding to protrusions of the present invention) are provided, and ribs 2 for the same purpose are provided.
47 is also provided on the outer surface of the inner casing 240 on the inflow portion 241 side. These ribs 246, 24
7 shows that when the highly corrosive absorbent stays near the surface of stainless steel, crevice corrosion occurs as abnormal corrosion, so that the outer casings 220 and 230 and the inner casing 2
This is to prevent crevice corrosion of the outer casings 220 and 230 made of stainless steel by reliably providing an interval between the outer casings 40 and 250 so that the absorbing liquid can easily move. Crevice corrosion, 0.1m spacing
m, the height of the ribs 246 and 247 is set to 0.5 mm and the height of the rib 24 is set to 0.5 mm.
The outer casings 220 and 230 and the inner casings 240 and 250 are brought into local contact at the points 6 and 247, and in other parts, corrosion is prevented by reliably providing an interval where the absorbing liquid can easily move. ing. In addition,
The thin wall portion 248 at the end of the outer edge wall 244 is a fitting portion for fitting with the annular inner casing 250.

The annular inner casing 250 is combined with the dish-shaped inner casing 240 to form a helical water passage, and has an annular shape as shown in FIG. A spiral groove 245 and a spiral groove 251 having a target shape are formed. The spiral groove 25
Reference numeral 1 denotes a portion that has circulated together with the spiral groove 245,
The discharge hole 252 penetrates through 44.

The impeller 211 disposed inside the inner casings 240 and 250 is
The shaft 212 is supported rotatably between two recesses 231 and the shaft receiving portion 242 of the dish-shaped inner casing 240 via two bushes 213 and 214. The impeller 211 is provided with a driven magnet 207 for receiving the magnetic force of the driving magnet 205 on the pot-shaped outer casing 230 side. Note that 215, 2 on both sides of the bushes 213, 214
Reference numeral 16 denotes a washer for smooth rotation of the bushes 213 and 214, and the impeller 211
2 and washers 215 and 216
13 and 214 rotate together.

The absorbing liquid pump 210 having the above configuration
Is welded in advance to the discharge port 232 of the pot-like outer casing 230,
The impeller 211 in which the bushes 213 and 214 are fitted in advance is inserted into the shaft 212 and the washers 215 and 216.
And the combined inner casings 240 and 250 are assembled, the O-ring 217 is attached to the dish-shaped inner casing 240, and the inlet-side pipe 221 is covered with the lid-shaped outer casing 220 to which the inlet pipe 222 has been welded in advance. The assembly is completed by welding the joining edge 233 of the outer casing 230 to the outer edge of the outer casing 220.

In the absorbent pump 210 assembled as described above, inside the welded portion between the pot-shaped outer casing 230 and the lid-shaped outer casing 220, heat during welding is prevented from being transmitted to the dish-shaped inner casing 240. So that the space for the dishing is formed.
Is provided with a heat-releasing depression 249 in the outer shape. Also, when the impeller 211 rotates, the high pressure absorbing liquid that has passed through the discharge holes 252 formed by the inner casings 240 and 250 causes the O-ring 217 to move to the outer casing 22.
0, 230 and the inner casings 240, 250, so that the discharge holes 252 and the inflow portions 241 at the intervals do not short-circuit into the inflow portion 241 of the dish-shaped inner casing 240. This is a seal member for cutting off the communication with the member. Here, a seal member made of fluoro rubber is used.

Further, in order to facilitate the movement of the solution,
A small hole A inside the rib 247 of the dish-shaped inner casing 240
(For example, about three places, see FIG. 5). In this case, some short circuit occurs only in the discharge port 252 side,
Since the pressure inside the dish-shaped inner casing 240 near the small hole A is large and does not short-circuit from the discharge hole 252 of the dish-shaped inner casing 240 into the inflow portion 241, there is no problem in the discharge capacity. Note that the arrangement position of the O-ring 217 is within a range where the communication between the discharge hole 252 and the inflow portion 241 can be cut off.
It may be on the outer peripheral side. Accordingly, a high discharge pressure can be secured without reducing the discharge capacity of the absorbent pump 210.

On the other hand, since the cold / hot water pump 260 does not need to secure high airtightness and does not need to secure a large discharge pressure unlike the absorbent pump 210, the front casing 261 made of resin is made of sheet metal. In the casing covered by the back casing 262 of the
An impeller 263 having a driven magnet 208 facing the motor 6 is rotatably arranged with respect to a shaft 264. The shaft 264 is fixed to a sheet metal back casing 262, and the impeller 263 is rotatably supported by the shaft 264 via bushes 265 and 266.

The tandem pump 200 having the above configuration
Is arranged at the lowermost part of the refrigerator main body 101 as shown in FIG. 7. For example, during the cooling operation, when the temperature in the high-temperature regenerator 1 is low, the rotation speed is low, and Control is performed such that the higher the temperature, the higher the rotation speed. Here, when the rotation speed of the tandem pump 200 is controlled to be low, the flow rate of the absorbent circulating in the absorption cycle decreases, but the heating tank 1 of the high-temperature regenerator 1
A high discharge pressure is required in order to feed the absorbing liquid into the liquid. Thus, even when the flow rate of the absorbing solution is small, the absorbing solution pump 210 of the tandem pump 200
Each spiral groove 2 of each resin inner casing 240, 250
Since the nozzles 45 and 251 are formed with high accuracy, a large discharge pressure can be secured, and the absorbing liquid can be reliably sent to the high-temperature regenerator 1 even at a low rotation speed. During the heating operation, the tandem pump 200 is controlled so that the rotation speed increases as the required heat amount in the air conditioning heat exchanger 44 for heating increases.

As described above, according to the present invention, in the absorption cycle, the casing of the absorbent pump that requires a high discharge pressure and requires airtightness to the outside is provided inside the outer casings 220 and 230 made of sheet metal and made of resin. The impeller chamber for accommodating the impeller 211 is constituted by a double-structured casing in which the inner casings 240 and 250 are arranged, and the resin inner casings 240 and 250 are used to form a complicated shape such as a dimension correlated with the impeller. With regard to (1), since high-precision molding can be performed in detail, a high-performance absorbent pump can be obtained. Also,
The outer sides of the resin inner casings 240 and 250 are formed by sheet metal outer casings 220 and 230 and can be joined by welding. Therefore, it is easy to ensure airtightness with the outside, and maintenance work is performed. Airtightness can be ensured for a long period of time without any problem.

Further, the double-structure casing is made of a resin-made inner casing 240, 250 and a sheet-metal outer casing 220, 230, which are formed by a manufacturing method suitable for mass production, so that the forming is easy. In addition, it is inexpensive. Further, in the resin inner casings 240 and 250, unnecessary waste portions are not generated, and it is easy to reduce the thickness without complicated work such as cutting, so that the weight is reduced. be able to. Therefore, mass production is easy, inexpensive, good in performance, and maintenance work for maintaining airtightness is unnecessary, so that it can be used for a long period of time, and the absorption refrigeration system is popularized as a household device. It becomes easier.

In the present invention, in the double-structure casing, the inner casings 240 and 250 made of resin and the outer casings 220 and 230 made of sheet metal are connected to the ribs 246 and 246.
By making local contact at a plurality of places by 47,
Inner casing 240, 250 and outer casing 22
The outer casing is formed in an absorption liquid pump in which an absorption cycle is formed by using a highly corrosive aqueous solution such as lithium bromide as an absorption liquid because an interval of a predetermined size or more is provided on a contact surface side with 0, 230. A substance that participates in corrosion (for example, a highly corrosive aqueous solution such as lithium bromide) does not stay on the surface of the stainless steel, and the aqueous solution can easily move.
Since the aqueous solution moves between the metal casings 0 and 250 and the outer casings 220 and 230 made of sheet metal to exchange corrosive substances, crevice corrosion does not progress in stainless steel or the like.

Further, resin inner casings 240 and 250 of a double-structure casing and sheet metal outer casing 2
20 and 230, an O-ring 217 for blocking communication between the inlet 221 and the outlet 232 of the absorbing liquid pump was attached to the space formed by the ribs 246 and 247. The discharge pressure generated on the discharge hole side of the inner casings 240 and 250 by rotation causes the inner casings 240 and 250 and the outer casing 220,
Even when the pressure is applied to the gap formed between the inner casing 240 and the inner casing 240, there is no short circuit caused by the pressure of the discharge holes of the inner casings 240 and 250 reaching the inflow portion 241 of the inner casings 240 and 250. , 250
Pressure on the discharge hole 252 side of the outer casing 22
0, 230 are added to the discharge port 232. Therefore, the discharge capacity of the absorbent pump 210 does not decrease.

In the above embodiment, in the absorbent pump,
Although the inner casing made of resin is divided into two parts in order to prevent undercut during molding, it may be formed by integral molding. Since crevice corrosion is likely to occur at 0.1 mm or less, in the above embodiment, the interval provided between the outer casing and the inner casing by the rib was set to 0.5 mm. Is also good. In the above embodiment, the rib is formed on the inner casing, but the rib may be formed on the outer casing 220, 230 side. In the above embodiment, the area of the contact portion at the tip of the rib is relatively large.
Since it is more advantageous for the area of the contact portion to be small, a convex protrusion may be formed so as to be a point-like contact portion as long as the accuracy of the molded shape is ensured.

In the above embodiment, in the absorbent pump,
The pot-shaped outer casing 230 is provided on the DC motor 201 side because it is unlikely to be an obstacle to assemblability with the DC motor 201.
, And the welded portions of the outer casings 220 and 230 are provided on the dish-shaped inner casing 240 side. However, the shape and the welded portions of the outer casing are not necessarily limited to the above-described shapes. In the above-described embodiment, the tandem pump in which the absorbent pump is provided integrally with the cold / hot water pump is shown. However, the tandem pump is not necessarily required, and the absorbent pump and the cold / hot water pump may be provided separately.

In the above embodiment, the cooling tower CT of the cooling water flow path 34 is of the open type in which a part of the cooling water is evaporated to self-cool the cooling water. However, a water cooling device that forms a closed circuit that is not open to the atmosphere may be used. In the above embodiment, only the air conditioner heat exchanger 44 is provided in the indoor unit RU. However, in order to perform the dehumidifying operation without lowering the room temperature, the air once cooled by the air conditioner heat exchanger 44 is heated. The heating heat exchanger may be provided in parallel with the air conditioning heat exchanger 44. Although the air conditioner using the absorption refrigeration apparatus has been described in the above embodiment, the air conditioning apparatus may be used for other refrigeration apparatuses such as a refrigerator and a freezer. In addition,
In the above embodiment, the double effect type is described, but a single effect type may be used.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of an air conditioner showing an embodiment of the present invention.

FIG. 2 is a sectional view showing a tandem pump according to the embodiment of the present invention.

FIG. 3 is a view showing a lid-shaped outer casing of the absorbent pump of the tandem pump of the embodiment, wherein (a) is a sectional view,
(B) is a front view.

FIG. 4 is a view showing a pot-like outer casing of the absorbent pump of the tandem pump according to the embodiment, wherein (a) is a cross-sectional view,
(B) is a front view.

FIG. 5 is a view showing a dish-shaped inner casing of the absorbent pump of the tandem pump of the embodiment, (a) is a front view,
(B) is a sectional view, and (c) is a rear view.

FIG. 6 is a view showing an annular inner casing of the absorbent pump of the tandem pump according to the embodiment, (a) is a front view,
(B) is a sectional view, and (c) is a rear view.

FIG. 7 is a perspective view showing the appearance of the refrigerator main body showing the arrangement of the tandem pump of the embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 High temperature regenerator (regenerator) 2 Low temperature regenerator (regenerator) 3 Absorber 4 Evaporator 5 Condenser 100 Absorption refrigeration apparatus 210 Absorbent pump 211 Impeller 217 O-ring (seal member) 220 Lid outer casing (sheet metal) 221 Inlet (inlet of absorbent pump) 230 Pot-shaped outer casing (sheet metal casing) 232 Discharge port (discharge port of absorbent pump) 240 Dish-shaped inner casing (resin casing) 246 247 Rib 250 Ring Inner casing (resin casing)

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) F25B 41/00 F04D 29/42 F25B 15/00

Claims (3)

(57) [Claims] 1. A regenerator that heats an absorbent containing a refrigerant to separate refrigerant vapor from the absorbent, a condenser that cools and condenses the refrigerant vapor separated by the regenerator, An evaporator for evaporating the condensed refrigerant under a low pressure, and an absorber for forming an absorption cycle from an evaporator for evaporating the refrigerant vapor evaporated by the evaporator into an absorbent supplied from the regenerator, An absorbent pump for returning an absorbent from the absorber to the regenerator, wherein a casing of the absorbent pump is formed of a resin casing for forming an impeller chamber for accommodating an impeller; and the absorption cycle includes the resin casing. An absorbent pump for an absorption refrigeration system, characterized in that the casing has a double-structured casing comprising a sheet metal casing for ensuring airtightness in the apparatus. 2. In the double-structured casing, the resin casing and the sheet metal casing are brought into local contact at a plurality of locations, and the contact surface side between the resin casing and the sheet metal casing is spaced apart by a predetermined distance or more. The absorption liquid pump for an absorption refrigeration system according to claim 1, wherein a plurality of protrusions for providing the chiller are provided on the resin casing or the sheet metal casing. 3. The communication between the inlet and the outlet of the absorbent pump is provided in the space formed by the protrusion between the resin casing and the sheet metal casing of the double-structure casing. 3. The absorption liquid pump for an absorption refrigeration system according to claim 2, further comprising a sealing member for blocking.