JP2012159229A - Refrigerator and refrigerating device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a refrigerator that can independently be used as only a refrigerator and also can be used for heating hot water supply.SOLUTION: In the refrigerator 2, a refrigerant takeout part 22 which takes out a hot gas refrigerant for supplying water in a hot water tank to a hot water heat exchanger and a refrigerant return part 23 which returns the hot gas refrigerant taken out from the refrigerant takeout part to the side of a condenser 13 are arranged at refrigerant piping at the refrigerant discharge side of a compressor 12, and at the same time, the refrigerator comprises a short circuit pipe 24 which is detachably attached to the refrigerant takeout part and the return part, and connects these parts.

Description

  Embodiments described herein relate generally to a refrigerator and a refrigeration apparatus connected to a refrigeration showcase or the like.

  2. Description of the Related Art Conventionally, a hot water supply system using exhaust heat from a refrigerator that heats and supplies hot water in a hot water supply tank by exhaust heat from a refrigerator connected to a refrigeration showcase or the like (see, for example, Patent Documents 1 and 2). .

  The hot water supply system using exhaust heat of a refrigerator described in Patent Document 1 mainly heats water stored in a hot water tank by exhaust heat of the refrigerator, and further includes an electric heater as an auxiliary heat source.

JP 2009-293839 A No. 2-30692

  However, in the inventions described in Patent Documents 1 and 2, the refrigerator is a dedicated model for combined use with hot water heating and is not assumed to be used alone.

  The present invention has been made in consideration of such circumstances, and the object thereof is to provide a refrigerator that can be used alone, and can also be used for heating hot water as needed. It is to provide. Moreover, it is providing the suitable operation control in the freezing apparatus which comprised the refrigerator as the heating combined use of hot water supply.

  According to the embodiment of the present invention, the refrigerator is supplied to the heat exchanger for hot water supply for heating the water in the hot water supply tank to the refrigerant pipe between the refrigerant discharge side of the compressor and the condenser. A refrigerant take-out part that takes out the hot gas refrigerant, a refrigerant return part that returns the hot gas refrigerant taken out from the refrigerant take-out part to the condenser side, and is detachably attached to the refrigerant take-out part and the return part so as to directly connect them. And a short-circuit tube.

  According to the embodiment of the present invention, the refrigeration apparatus sequentially connects a compressor, a condenser, a load-side expansion valve, and an evaporator with refrigerant piping, and the refrigerant discharge side of the compressor, the condenser, In the refrigerant pipe between the refrigerant outlet, a refrigerant take-out portion for taking out the hot gas refrigerant and a refrigerant return portion for returning the hot gas refrigerant taken out from the refrigerant take-out portion to the condenser are provided, and the compressor connected to the refrigerant take-out portion and the return portion And a hot water supply heat exchanger through which hot gas refrigerant is passed, and a refrigeration apparatus including a hot water supply tank capable of supplying hot water for storing water to be heat exchanged with the hot water supply heat exchanger.

  In addition, the refrigeration system is set so that the high pressure side pressure sensor for detecting the pressure on the high pressure side of the compressor and the high pressure side pressure detection value detected by the high pressure side pressure sensor maintain the lower limit temperature at which the hot water tank can supply hot water. A controller having fan rotation speed control means for controlling the rotation speed of the fan motor of the condenser so as not to drop below the set pressure value on the high pressure side.

  Furthermore, according to the embodiment of the present invention, the refrigeration apparatus sequentially connects a compressor, a condenser, a load-side expansion valve and an evaporator with a refrigerant pipe, the refrigerant discharge side of the compressor, the condenser, The refrigerant pipe between the refrigerant outlet and the refrigerant take-out section for taking out the hot gas refrigerant and the refrigerant return section for returning the hot gas refrigerant taken out from the refrigerant take-out section to the condenser are provided, and connected to the refrigerant take-out section and the return section from the compressor. A hot water supply heat exchanger through which the hot gas refrigerant is passed and a refrigeration apparatus having a hot water supply tank capable of supplying hot water for storing water to be exchanged with the hot water heat exchanger.

  Further, the refrigeration apparatus includes a hot water supply temperature sensor that detects a temperature of a return refrigerant pipe through which refrigerant returned from the hot water supply heat exchanger to the refrigerant return portion side, a liquid side refrigerant pipe and a gas side refrigerant pipe to which an evaporator is connected. An auxiliary heat exchanger that exchanges heat between a bypass pipe that connects between the liquid refrigerant from the liquid side pipe that is interposed in the middle of the bypass pipe and connects to the condenser, and a refrigerant from the heat exchanger for hot water supply, A normally closed bypass valve interposed in the middle of the bypass pipe, an expansion valve interposed between the bypass valve and the auxiliary heat exchanger, a low pressure side pressure sensor for detecting the low pressure side pressure of the compressor, The low pressure side pressure detection value detected by the low pressure side pressure sensor is lower than the low pressure side pressure set value when the operation of the evaporator is stopped, and the hot water supply temperature detection value detected by the hot water supply temperature sensor is supplied. Hot water supply temperature setting that is the temperature of the stored water When the pressure is higher than the value, the compressor operation is stopped, the low pressure side pressure detection value detected by the low pressure side pressure sensor is lower than the low pressure side pressure setting value for shutdown, and the hot water supply temperature detection value is the hot water supply temperature setting. And a bypass on-off valve control means for opening the bypass on-off valve for a predetermined time and continuing the operation of the compressor when lower than the value.

The block diagram which mainly shows the refrigerating cycle of the freezing apparatus using the refrigerator which concerns on the 1st Embodiment of this invention. The graph which shows the change of a fan motor rotation speed when controlling the rotation speed of the fan motor of a condenser with the refrigerator side controller shown in FIG. The graph which shows the change of the high pressure side pressure (discharge pressure) of a compressor similarly. The graph which shows the temperature change of the hot gaseous refrigerant | coolant (hot gas) of a compressor similarly. The flowchart which shows the control method of the fan motor rotation speed control means of the refrigerator side controller shown in FIG. The flowchart which shows the determination method of the connection state determination means of the refrigerator side controller shown in FIG. The flowchart which shows the abnormality alarm output method by the abnormality alarm output means of the refrigerator side controller shown in FIG. The block diagram which mainly shows the refrigerating cycle of the freezing apparatus which concerns on the 2nd Embodiment of this invention. The flowchart which shows the control method of the bypass valve control means of the refrigerator side controller shown in FIG. The block diagram which mainly shows the refrigerating cycle of the freezing apparatus which concerns on the 3rd Embodiment of this invention. Control when continuing the operation of the compressor so that hot water can be supplied when the suction side pressure of the compressor is lowered by the load (showcase) side controller capable of bidirectional communication with the refrigerator side controller shown in FIG. The flowchart which shows a method. The flowchart which shows the control method of the load side controller which controls the load side so that hot water supply is possible when the low pressure side pressure of a compressor falls. The flowchart connected to the connector circle A shown in FIG. The flowchart connected to the connector circle | round | yen B shown in FIG. The flowchart which shows the control method of the load side controller in the case of shortening the boiling time of hot water supply. The flowchart which shows the control method in the case of performing the defrost operation of a 1st-4th showcase with a load side controller.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In addition, the same code | symbol is attached | subjected to the same or an equivalent part in several drawing.

(First embodiment)
As shown in FIG. 1, the refrigeration apparatus 1 according to the first embodiment is installed in a convenience store, for example, and the refrigerator 2 is connected to a refrigerator main body 7 by a liquid side refrigerant pipe 8 and a gas side refrigerant pipe 9. , And a plurality of refrigeration or cooling showcases 10, 10,.

  Furthermore, the hot water supply heat exchanger 4 of the hot water supply tank 3 can be connected to the extraction refrigerant pipe 5 and the return refrigerant pipe 6 for use in the refrigerator 2.

  In the refrigerator main body 7, a compressor 13 and a condenser 13, which is an outdoor heat exchanger for exchanging heat with the outside air, are connected by a refrigerant pipe 14 in a refrigerator casing 11 made of sheet metal. The refrigerant pipe 14 is divided on the way from the outlet side of the condenser 13 to the suction port of the compressor 12, and the gas refrigerant inlet 15 and the liquid refrigerant outlet 16 at both ends of the refrigerant pipe 14 slightly protrude outward from the outer surface of the housing 11. In addition, a half union, which is a pipe connector that can connect the liquid-side refrigerant pipe 8 and the gas-side refrigerant pipe 9, is provided at the ends of both protruding end portions.

  The refrigerator main body 7 is provided with one or more fans 17 in the condenser 13, and the refrigerant pipe 14 is provided with a discharge temperature sensor 18 on the discharge side of the compressor 12, and condensed on the refrigerant inlet side of the condenser 13. A vessel inlet temperature sensor 19 is provided.

  Further, the refrigerant pipe 14 is provided with a low pressure side pressure sensor 20 on the low pressure side from the gas refrigerant inlet 15 to the suction port of the compressor 12, and on the high pressure side from the condenser 13 outlet to the liquid refrigerant outlet 16b. A pressure sensor 21 is provided.

  And in the refrigerator main body 7, the middle of the refrigerant | coolant piping 14 which connects the exit (discharge) of the compressor 12 and the inlet of the condenser 13 is parted, and the refrigerant | coolant extraction part 22 is connected to the compressor 12 side one end of the parting part. And one end on the condenser 13 side is formed in the refrigerant return portion 23.

  Each of the refrigerant take-out portion 22 and the return portion 23 is also provided with a half union that is a pipe connector. At the time of shipment of the refrigerator 2, both ends of the detachable short-circuit tube 24 are attached to the half union as shown by a dotted line in FIG. 1, and the refrigerant take-out part 22 and the refrigerant return part 23 are directly connected. Yes.

  The refrigerant takeout unit 22 is a pipe for taking out hot gas refrigerant to be supplied to the hot water supply heat exchanger 4 for heating the water in the hot water supply tank 3, and the refrigerant return unit 23 is taken out from the refrigerant takeout unit. This is a pipe for returning the hot gas refrigerant after passing through the hot water supply heat exchanger 4 to the condenser 13 side.

  Since the refrigerant unloading section 22 and the refrigerant unloading section half union and the short-circuit tube 24 are housed in the refrigerator casing 11, they are not exposed to rainwater, and the durability is improved. Since it does not protrude out of the housing 11, the appearance is good.

  An opening that can be opened and closed is formed on a part of the side surface of the refrigerator casing 11 where the leading ends of the refrigerant unloading part 22 and the refrigerant return part 23 face each other. As shown in FIG. 1, when hot water is supplied using the exhaust heat of the refrigerator 1, the short circuit tube 24 is removed from each half union of the refrigerant take-out part 22 and the refrigerant return part 23, and instead the refrigerant take-out part The extraction refrigerant pipe 5 is connected to 22, and the return refrigerant pipe 6 is connected to the refrigerant return portion 23.

  The short-circuit tube 24 has a U-shape or a U-shape, and is formed of a copper tube having a certain thickness so that the refrigerant can flow without great resistance. When short-circuiting between the respective half unions of the refrigerant take-out section 22 and the refrigerant return section 23 using the short-circuit tube 24, if the length of the short-circuit tube 24 is short, an error in the length of the short-circuit tube 24 and the dimension between the half unions. When misalignment occurs, connection work becomes difficult. If the copper tube has a certain length, it can be slightly adjusted by plastic deformation and can be connected even if both dimensions are in error. On the other hand, if the short-circuit tube 24 is long, the heat radiation at this portion is wasted, and the opening on the side surface of the refrigerator housing 11 becomes too large, and the member to be closed becomes large. Therefore, it is desirable that the length of the short-circuit tube 24 (the U-shaped or U-shaped longitudinal portion), that is, the dimension between the half unions of the refrigerant take-out portion 22 and the return portion 23 is in the range of 10 to 25 cm. If possible, about 20 cm is preferable.

  In addition, the refrigerator main body 7 is provided with a refrigerator-side controller 25 in the casing 11, and a connection state manual setting device 26 is provided inside or on the outer surface side of the casing 11.

  The connection state manual setting device 26 is a slide switch for setting whether or not the extraction refrigerant pipe 5 and the return refrigerant pipe 6 are connected to the refrigerant extraction portion 22 and the return portion 23 after the short-circuit tube 24 is removed. Etc. In the connection state manual setting device 26, either “connected” or “not connected” is set by manually sliding the slider between the two positions “connected” and “not connected”. The This manual setting is set, for example, by a contractor who installs the refrigerator main body 7 at a required place and constructs piping work at the installation site. At the time of shipment of the refrigerator 2, the short circuit tube 24 is attached to the refrigerant take-out part 22 and the return part 23, so the connection state manual setting device 26 is set to the “non-connection” side.

  The connection state manual setting device 26 is connected to the refrigerator-side controller 25 via a signal line (not shown), and the setting state of “connected” or “not connected” of the setting state is read by the refrigerator-side controller 25. It is.

  The refrigerator main body 7 has gas-side refrigerant pipes 9 on the showcases 10, 10,..., Which are an example of a refrigeration load, via the heat exchanger 27, in each half union of the gas refrigerant inlet 15 and the liquid refrigerant outlet 16. Each is connected to the liquid side refrigerant pipe 8. The heat exchanger 27 is provided when the hot water supply heat exchanger 4 of the hot water supply tank 3 is connected to the extraction refrigerant pipe 5 and the return refrigerant pipe 6, and is connected to the extraction refrigerant pipe 5 and the return refrigerant pipe 6. Even when it is used as a general refrigerator 2 with the short tube 24 connected, it may be used when it is desired to increase the condensation temperature.

  The heat exchanger 27 is heated by heat exchange tubes 27a and 27b through which the low-temperature gas refrigerant flowing into the gas refrigerant inlet 15 of the refrigerator main body 7 and the slightly high-temperature liquid refrigerant discharged from the liquid refrigerant outlet 16 side respectively pass. To be exchanged. In the heat exchanger 27, the low-temperature gas refrigerant is heated by the high-temperature liquid refrigerant, and the temperature rises.

  Each of the plurality of showcases 10, 10,..., The unit cooler 28 and a load-side expansion valve (not shown) and an evaporator connected in series are connected in parallel to the liquid refrigerant pipe 8. ing. The opening degree of these expansion valves is adjusted to a required opening degree according to the respective cooling set temperatures by the installation contractor of the showcases 10, 10,. In addition, a stop valve 29 made of an electromagnetic valve or the like is interposed in the liquid side refrigerant pipe 8 on the upstream side of the expansion valves of the showcases 10, 10,.

  On the other hand, the hot water supply tank 3 is accommodated in the tank housing 3a. A hot water supply heat exchanger 4 is accommodated in the hot water supply tank 3 while being immersed in the water in the hot water supply tank 3. The hot water supply heat exchanger 4 is configured by a double pipe in which a stainless steel pipe is tightly fitted on the outside of an inner pipe made of copper pipe so as not to corrode and withstand long-term use in water.

  The hot water supply heat exchanger 4 has a pair of connecting refrigerant pipes 30 and 31 connected to both ends at the inlet and outlet sides. Both ends of the pair of connecting refrigerant pipes 30 and 31 protrude slightly outward from one surface of the tank housing 3a, and half unions 32 and 33, which are pipe connection parts, are provided at the protruding ends. The extraction refrigerant pipe 5 and the return refrigerant pipe 6 are detachably connected to the half unions 32 and 33, respectively.

  When the compressor 12 is operated, the high-temperature gas refrigerant discharged from the compressor 12 flows into the hot water supply heat exchanger 4 through the extraction cold pipe 5, the half union 32, and the inlet-side connection refrigerant pipe 30. Then, heat is exchanged with water in the hot water supply tank 3 to heat the water, and then flows to the condenser 13 through the outlet connection refrigerant pipe 31, the half union 33, and the return refrigerant pipe 6. In the middle of the outlet side connection refrigerant pipe 31, a hot water supply temperature sensor 34 is disposed inside the tank housing 3a. This hot water supply temperature sensor 34 detects the temperature of the outlet side connection refrigerant pipe 31 as the hot water supply temperature. The hot gaseous refrigerant passing through the outlet side connection refrigerant pipe 31 heats the water stored in the hot water supply tank 3 by the hot water supply heat exchanger 4 and then passes through the outlet side connection refrigerant pipe 31. The temperature of the side connection refrigerant pipe 31 is substantially equal to the water (hot water) temperature in the hot water supply tank 3. When the hot water supply heat exchanger 4 of the hot water supply tank 3 is not connected to the extraction refrigerant pipe 5 and the return refrigerant pipe 6, that is, the short-circuit pipe 24 is connected to the extraction refrigerant pipe 5 and the return refrigerant pipe 6. When the compressor 12 is operated, the high-temperature gas refrigerant discharged from the compressor 12 flows into the condenser 13 through the short-circuit tube 24 when the compressor 12 is used. .

  The hot water supply tank 3 includes a water supply pipe 35 and a hot water supply pipe 36. The water supply pipe 35 has a pressure reducing valve 37 and a check valve 38 connected in series on the way, and an external water supply system 40 is connected to an inlet of the water supply pipe 35 via a water supply fitting 39 with a strainer. The external water supply system 40 is generally a city water tap. The hot water supply pipe 36 has a pressure relief valve 41 and a hot water outlet fitting 42, and an external hot water supply system 43 is connected to the hot water outlet fitting 42, and hot water is supplied from the external hot water supply system 43 to a required location.

  The refrigerator-side controller 25 is constituted by, for example, a microprocessor, and has a ROM that stores a control program, a CPU that sequentially reads and executes instructions of the control program from the ROM, and a RAM that forms a data storage area at that time. In addition, it has a function of a rotational speed control means of a fan motor (FM). The solid line in FIG. 2 indicates that the fan rotation speed control means maintains hot water stored in the hot water supply tank 3 at or above a predetermined hot water temperature lower limit that allows hot water supply even when the outside air temperature is low (for example, 10 ° C. or lower). As indicated by A, the rotational speed of the drive motor of the fan 17 of the condenser 13 is controlled. In FIG. 2, the broken line B indicates that the fan 17 based on the outside air temperature when the hot water supply tank 3 is not connected, that is, when the short circuit tube 24 is connected between the half unions of the refrigerant take-out part 22 and the return part 23. Indicates the control state of the rotational speed.

  In the connection state manual setting device 26, when the setting state is set to “not connected”, that is, the hot water supply tank 3 is not connected, the fan rotation speed control means is the same as the conventional refrigerator, In order to control the pressure and temperature of the refrigerant within an appropriate range, the rotational speed of the fan 17 is uniquely determined and controlled according to the outside air temperature. Specifically, when the outside air temperature is lower than about 5 ° C., the fan speed is controlled to be low, and when the outside air temperature is in the range of about 5 ° C. to 15 ° C., the fan speed is increased in proportion to the rise in outside air temperature. When the temperature exceeds 15 ° C., the fan speed is controlled at a constant high speed.

  FIG. 5 is a flowchart of a control program showing a control method of the fan rotation speed control means when the connection state manual setting device 26 is set to “connected”, that is, the hot water supply tank 3 is connected. In the following flowcharts, reference numerals with numerals added to S indicate steps.

  As shown in FIG. 5, the fan rotation speed control means first determines whether or not the high pressure side pressure detection value Pd detected by the high pressure side pressure sensor 21 in the refrigeration cycle is lower than the high pressure side pressure set value Ps in S1. That is, it is determined whether Pd <Ps is satisfied.

  The high pressure side pressure detection value Pd is substantially proportional to the high temperature and high pressure gaseous refrigerant discharged from the compressor 12, that is, the discharge pressure and temperature of the hot gas. The temperature is low. When the hot gas temperature is low, the heating temperature at which the hot gas passes through the hot water supply heat exchanger 4 and heats the stored water (hot water) in the hot water tank 3 is low. It may not be possible to heat to a temperature exceeding. In this case, hot water at a temperature required by the external hot water supply system 43 cannot be supplied from the hot water storage in the hot water supply tank 3. For this reason, it is necessary to reduce the amount of heat released by the condenser 13 by decelerating the number of revolutions (rpm) of the motor of the fan 17 of the condenser 13 per unit time, thereby increasing the amount of heat held by the refrigerant.

  Therefore, the high pressure side pressure set value Ps is set to the high pressure side pressure of the refrigeration cycle corresponding to the lower limit value of the hot water temperature at which hot water can be supplied from the hot water tank 3 to the external hot water system 43.

  If the outside air temperature falls to a predetermined value, for example, 10 ° C. or less, in S1, Yes, that is, if this high pressure side pressure detection value Pd <high pressure side pressure set value Ps is established, the condenser in S2 The rotational speed R (rpm) of the motor of the 13 fans 17 per unit time is repeatedly reduced (decelerated) until the high pressure side pressure detection value Pd becomes equal to the high pressure side pressure set value Ps (Pd = Ps).

  As a result, the amount of heat released from the condenser 13 can be reduced, and the amount of heat held by the high-pressure refrigerant can be increased, so that the refrigerant returns to the compressor 12 again, where it is adiabatically compressed and discharged at a high temperature and pressure. The temperature of the refrigerant, that is, the hot gas can be increased to a value equal to or higher than the lower limit of the hot water supply temperature at which hot water can be supplied.

  For this reason, hot water can be supplied even when the outside air temperature is as low as 10 ° C. or less.

  On the other hand, if S1 is No, that is, if Pd <Ps is not established, that is, if the high-pressure side pressure detection value Pd is higher than the high-pressure side set value Ps, the rotation speed R of the fan 13 is increased in the next S3. (Acceleration) to increase the amount of heat release, thereby preventing the refrigerant from being heated.

  In the next S4, it is determined whether or not the speed R of the accelerated fan 13 is smaller than a preset speed setting value F (T0) (F (T0)> R). The rotation speed setting value F (T0) is a rotation speed setting value when the hot water supply tank 3 is not connected. This rotational speed set value F (T0) is used as the upper limit value of the rotational speed R of the fan 13 based on the outside air temperature when the hot water supply tank 3 is connected.

  If No in S4, that is, if F (T0)> R is not established, the process returns to S1 again, and the steps after S1 are repeated. On the other hand, if S4 is Yes, that is, if F (T0)> R is satisfied, in the next S5, the rotational speed R is equal to the rotational speed setting value F (T0) (R = F (T0)). Control to be. As a result, in S3 to S5, the rotational speed is increased within a range in which the rotational speed R does not exceed the rotational speed setting value F (T0).

  Therefore, in general, in a state where the outside air temperature is lower than a predetermined temperature (for example, 10 ° C.), in order to increase the temperature of the hot gas, compared with the case of the broken line B where the hot water supply tank 3 shown in FIG. The rotational speed R of the fan 13 is controlled to be low as indicated by the solid line A when the tank 3 is connected.

  On the other hand, when the outside air temperature exceeds a predetermined temperature (for example, 10 ° C.), the temperature of the hot gas is originally high, so the solid line A and the broken line B in FIG. 2 coincide and are preset in the fan motor speed control means. The rotational speed R is controlled so that the rotational speed setting value F (T0) is obtained. As a result, the rotational speed R of the fan 13 increases as the outside air temperature rises, and the amount of heat released from the condenser 13 gradually increases. Therefore, hot heat due to insufficient heat radiation in the condenser 13 under high outside air temperature conditions. Gas overheating can be prevented.

  The case where the fan is controlled based on the rotational speed setting value when the hot water supply tank 3 is not connected even though the hot water supply tank 3 is connected to FIGS. 3 and 4 is indicated by a broken line B, and the fan rotation shown in FIG. A case where the number control is applied is indicated by a solid line A, and the difference will be described. When the fan rotation speed control shown in FIG. 5 is applied, the high pressure side pressure detection value Pd does not drop below the lower limit value for hot water supply as shown by the solid line A in FIG. For this reason, as shown by the solid line A in FIG. 4, the hot gas temperature does not decrease below the lower limit value for hot water supply. On the other hand, when the fan speed is controlled only by the outside air temperature, when the outside air temperature decreases, the high pressure side pressure detection value Pd decreases as shown by the broken line B in FIG. 3, and the broken line B in FIG. As shown, the hot gas temperature falls below the lower limit of hot water supply, and hot water supply at a desired temperature cannot be performed from the hot water supply tank 3.

  In the above description, the refrigerator state controller 25 discriminates the connection state of the hot water supply tank 3 by reading the setting state in the connection state manual setting device 26, and the fan rotation speed control is switched. However, when the connection state manual setting device 26 is used, the connection state manual setting device 26 is eliminated in order to prevent the contractor from forgetting the setting or making an incorrect setting and to simplify the construction. A discharge temperature detection value Td detected by the discharge temperature sensor 18 and a condenser inlet temperature detection value Tc detected by the condenser inlet temperature sensor 19 are used for the machine-side controller 25, and the hot water supply tank 3 according to these temperatures. An example in which connection state determination means for automatically determining “connection” and “non-connection (a state in which the short circuit tube 24 is connected)” is provided will be described. Note that, similarly to the connection state manual setting device 26 described above, this connection state determination means also switches the control operation of the fan rotation speed control means and the like executed by the refrigerator controller 25 according to the determination result.

  FIG. 6 is a flowchart for explaining a connection state determination method by the connection state determination means of the refrigerator-side controller 25 described above.

  This connection state determination means first determines whether or not the power of the refrigerator 2 is turned on in S11, and when Yes, starts the compressor 12 in the next S12.

  Thereafter, in S13, it is repeatedly determined whether or not the predetermined time a has elapsed after the compressor 12 is started, or whether or not the compressor 12 is operated at the predetermined frequency bHz or more. When it is determined that the predetermined time a has elapsed after the machine 12 is started, or when it is determined that the compressor 12 is operating at the predetermined frequency Hz, it is determined that the operation of the compressor 12 is stable, and the next S14 Proceed to Note that the refrigerator-side controller 25 of the present embodiment includes an inverter device that drives the compressor 12 at a variable speed by varying the frequency supplied to the motor of the compressor 12 therein.

  In S14, the discharge temperature detection value Td detected by the discharge temperature sensor 18 and the condenser inlet temperature detection value Tc detected by the condenser inlet temperature sensor 19 are substantially equal (Td≈Tc) for a predetermined time ( In the case of Yes, that is, when Td≈Tc continues for c minutes, the hot water supply tank 3 is not connected to the refrigerator main body 7 in the next S15, that is, The refrigerator-side controller 25 determines that it is in the “not connected” state, and executes operation control as a normal refrigerator 2 to which the hot water supply tank 3 is not connected.

  That is, when the short circuit pipe 24 is attached to the refrigerant take-out part 22 and the refrigerant return part 23 of the refrigerator main body 7 and both are short-circuited (connected), the discharge temperature detection value Td and the condenser inlet temperature detection value Since Tc is equal (Td = Tc), when the state in which Td≈Tc is established continues for a predetermined time (c minutes), the hot water supply tank 3 is not connected to the refrigerator main body 7, that is, “not connected”. It is in the state of. Note that a considerably long time such as 20 minutes is set for c minutes. Since the short-circuit tube 24 is a very short pipe, it is considered that the hot water supply tank 3 is not connected to the refrigerator main body 7 if Td≈Tc is not established even once.

  On the other hand, in the case of No in S14, that is, when Td≈Tc does not continue for c minutes, for example, it is determined that the hot water supply tank 3 is connected to the refrigerator main body 7 and “connected” to a display device (not shown). Is displayed to enable control of the hot water supply tank 3 side. When the hot water supply tank 3 is connected to the refrigerator main body 7, the high-temperature (Td) hot gas refrigerant that has flowed out of the refrigerant outlet 22 exchanges heat with the water in the hot water supply tank 4 in the hot water supply heat exchanger 4. . Thereafter, the temperature of the refrigerant after heat exchange returning to the refrigerant return section 23 is generally Tc ≦ Td because its temperature (Tc) is lowered. Based on this point, it is possible to determine “connected” / “not connected”.

  The determination of Td≈Tc is theoretically possible with Tc ≦ Td, but in reality, the difference between Td and Tc is within a range of about ± 1 ° C. in consideration of the reading error of each temperature sensor. In other words, it is desirable to satisfy the condition that Td-1 ° C <Tc <Td + 1 ° C.

  According to this connection state determination means, the connection state can be automatically determined without the connection state manual setting device 26.

  Note that during the period in which the determination in S14 is being performed (maximum c minutes), the refrigerator-side controller 25 treats the hot water supply tank 3 as a disconnected state, and controls as a normal refrigerator without the hot water supply tank 3 connected thereto. Execute. Further, when a state where Td≈Tc is not established is detected in the middle of the determination period in S14, it is determined that the hot water supply tank 3 is connected to the refrigerator main body 7 at that time (No in S12). The refrigerator side controller 25 executes hot water supply side connection control when the hot water supply tank 3 is connected.

  Subsequently, both the connection state manual setting unit 26 and the connection state determining unit are provided, and the matching state between the connection state set by the connection state manual setting unit 26 and the determination result of the connection state by the connection state determining unit is checked. A case will be described in which an abnormal alarm is output to prompt the contractor to confirm the construction status. The abnormality alarm output means for performing the abnormality alarm output is a function provided in the refrigerator-side controller 25 as in the connection state determination means.

  FIG. 7 is a flowchart for explaining an abnormality alarm output method of the abnormality alarm output means of the refrigerator-side controller 25.

  This abnormality alarm output means executes the same steps from S11 to S14 of the connection state determination means shown in FIG. 6, and in S14, in the case of Yes, that is, when Td≈Tc continues for a predetermined time (c minutes). In the next S17, the setting of the connection state manual setting device 26 is read, and it is determined whether or not the setting is set to the “not connected” side. In the case of Yes, “not connected” is illustrated in the next S18. It is displayed on the display device that does not, and only the refrigerator 2 can be controlled.

  However, in the case of No in S17, that is, when the automatic determination result of “not connected” and the manual setting result of “connected” by the connection state manual setting unit 26 do not match, either of the automatic determination or manual setting Is determined to be an error, an abnormal alarm is displayed on the display device in S19, etc., and the construction contractor is urged to confirm.

  Further, in the case of No in S14, that is, when Td≈Tc has not continued for c minutes, it is read in S20 whether or not the connection state manual setting device 26 is manually set to the “connection” side, and “connection”. If it is manually set to the side (Yes), “connection” is displayed on the display device in the next S21 to enable control of hot water supply operation, for example, fan rotation speed control shown in FIG.

  On the other hand, if No in S20, that is, if the read result read from the connection state manual setting device 26 is manually set to the “connected” side, an abnormality alarm is displayed on the display device in S22, etc. To issue a report.

  Therefore, according to the refrigeration apparatus 1, whether or not the hot water supply tank 3 is connected to the refrigerator main body 7 is automatically determined, and the automatic determination result matches the manual setting result of the connection state manual setting device 26. In this case, the state “connected” or “not connected” is displayed, and if the automatic determination result and the manual setting result of the connection state manual setting device 26 do not match, an abnormality alarm is output, so such connection The status can be checked twice.

  Next, the operation of the refrigeration apparatus 1 will be described.

  When the refrigerator main body 7 is shipped from the factory, a short-circuit tube 24 is attached to the refrigerant take-out part 22 and the refrigerant return part 23, and the two are directly connected. In this state, since the refrigerant extraction section 22 and the refrigerant return section 23 are not connected to the extraction refrigerant pipe 5 and the return refrigerant pipe 6 on the hot water tank 3 side, the connection state manual setting device When 26 is provided, it is set to the “not connected” side at the factory.

  On the other hand, the installation contractor of the refrigerator main body 7 connects the gas side heat exchange pipe 27 b of the heat exchanger 27 to the half union 32 of the gas refrigerant inlet 15 of the refrigerator main body 7.

  Further, the liquid side heat exchange tube 27 a of the heat exchanger 27 is connected to the half union 33 of the liquid refrigerant outlet 16 of the refrigerator main body 7.

  Further, the liquid side refrigerant pipe 8 and the gas side refrigerant pipe 9 are respectively connected to the liquid and gas side heat exchange pipes 27a and 27b of the heat exchanger 27 to constitute the refrigerator 2.

  On the other hand, the refrigerant supply section 5 and the return refrigerant pipe 6 on the hot water supply side are connected to the refrigerant unloading section 22 and the half return of the refrigerant return section 23 after the short-circuit tube 24 of the refrigerator body 7 is removed, thereby The machine 2 can be configured as a refrigeration apparatus 1 that also serves as a heat source for a water heater. Moreover, if the short circuit tube 24 is still attached to the refrigerator main body 7, the refrigeration apparatus 1 can be used exclusively for freezing. When the hot water supply tank 3 is connected to the refrigerator main body 7, the connection state manual setting device 26 is manually set to the “connected” side by the contractor.

  Next, an operation when the refrigeration apparatus 1 is used for both freezing and hot water supply will be described.

  First, hot gas, which is a high-temperature and high-pressure gas refrigerant discharged from the compressor 12, passes through the hot water supply heat exchanger 4 in the hot water supply tank 3 through the refrigerant extraction portion 22 and the hot water supply side extraction refrigerant pipe 5, Water storage (hot water storage) in the hot water supply tank 3 is heated.

  The hot gas that has passed through the hot water supply heat exchanger 4 is returned again to the refrigerant return portion 23 of the refrigerator main body 7 through the return refrigerant pipe 6 and flows into the condenser 13.

  In the condenser 13, the heat of the hot gas is dissipated to the outside air, and is condensed and liquefied. This amount of heat radiation is controlled by the rotational speed of the fan 17.

  The refrigerant liquefied in the condenser 13 passes through the liquid body heat exchange pipe 27a of the heat exchanger 27, the liquid side refrigerant pipe 8 and the stop valve 29 in order from the refrigerator body 7 to a plurality of showcases 10, 10,. .., And the decompression valves (not shown) in the unit cooler 28, and then evaporates in each evaporator, absorbs heat from the outside air by the latent heat of vaporization of the liquid refrigerant, and surrounds the surroundings. .., And the unit cooler 28, while flowing out to the gas side refrigerant pipe 9 as a gas refrigerant. The opening degree of each expansion valve is set in advance by a contractor so that the required cooling temperature of the showcases 10, 10,.

  The low-temperature gas refrigerant flowing out to the gas-side refrigerant pipe 9 is heated by the high-temperature liquid refrigerant passing through the liquid-side heat exchange pipe 27a when passing through the gas-side heat exchange pipe 27b of the heat exchanger 27, and again the compressor. 12 is sucked into the suction side of 12 and is adiabatically compressed again by the compressor 12, and the above-described operation is repeated. As a result, the showcases 10, 10,... And the unit cooler 28 are cooled to a required set temperature, and the stored water (hot water) in the hot water supply tank 3 is heated. Hot water can be supplied, and hot water is supplied at any time.

  When the high pressure side pressure detection value Pd of the high pressure side pressure sensor 21 of the refrigerator main body 7 becomes lower than the set value Ps (Pd <Ps) due to a decrease in the outside air temperature or the like, the fan rotation of the refrigerator side controller 25 is performed. The number control means controls the rotational speed (rpm) of the fan 17 of the condenser 13 to decrease (decelerate).

  Since this high pressure side pressure set value Ps is set to a high pressure side pressure corresponding to the lower limit value of the hot water supply temperature at which hot water can be supplied, the hot water supply temperature is maintained above the lower limit value.

  For this reason, even when the outside air temperature is low (for example, 10 ° C. or less), the refrigerator 2 can be operated and hot water having a hot water supply temperature equal to or higher than the lower limit value can be supplied.

  Further, when the high pressure side pressure detection value Pd is higher than the set value Ps, control is performed so that the rotation speed of the fan 17 is not set to be equal to or higher than the rotation speed setting value F (T0) set in advance based on the outside air temperature. Therefore, it is possible to prevent overheating of the hot gas and thus overheating of the hot water supply temperature.

  Further, the heat exchanger 27 heats the gas refrigerant from the showcases 10, 10,... And the unit cooler 28 with the high-temperature liquid refrigerant from the condenser 13, and then returns the refrigerant to the compressor 12. The suction temperature can be increased. For this reason, since the temperature of the hot gas discharged from the compressor 12 can be raised, the hot water supply temperature in the hot water supply tank 3 can be raised accordingly. That is, the heating efficiency can be increased.

  Furthermore, since the heat exchanger 4 for hot water supply is composed of a double pipe in which a stainless outer pipe is in close contact with a copper inner pipe, corrosion can be reduced with the stainless steel pipe and heat conduction efficiency is improved with the copper pipe. it can. Further, when the connection state determination means of the refrigerator side controller 25 is provided, it can be automatically determined whether or not the hot water supply tank 3 is connected to the refrigerator main body 7, and the automatic determination result and the manual setting can be made. When the manual setting by the device 26 is different, a warning can be given.

(Second Embodiment)
FIG. 8 is an overall configuration diagram mainly showing a refrigeration cycle of the refrigeration apparatus 1A according to the second embodiment of the present invention. As shown in FIG. 8, the refrigeration apparatus 1 </ b> A is characterized in that an auxiliary heat exchanger 50 is interposed downstream of the heat exchanger 27 in the refrigeration apparatus 1 shown in FIG. 1.

  That is, between the heat exchanger 27 and the showcase 10, 10,..., The refrigerant inlet side of the bypass pipe 51 to which the auxiliary heat exchanger 50 is connected is connected to the liquid side refrigerant pipe 8 on the other hand. The refrigerant outlet side of the bypass pipe 51 is connected to the gas side refrigerant pipe 9. That is, the auxiliary heat exchanger 50 is connected between the liquid side refrigerant pipe 8 and the gas side refrigerant pipe 9 in the same manner as the showcases 10, 10,.

  The bypass pipe 51 is provided with an auxiliary heat exchanger 50 in the middle, and a normally closed bypass valve including an expansion valve 52 and an electromagnetic valve on the upstream side (liquid side refrigerant pipe 8) side of the auxiliary heat exchanger 50. 53 are interposed in this order.

  The auxiliary heat exchanger 50 is composed of, for example, a plate heat exchanger, and is configured to contact and fix the remaining heat side heat exchanging part 50a and the heat receiving side heat exchanging part 50b to each other, and the refrigerant flowing in the heat exchanging parts 50a and 50b. Heat exchange. The remaining heat side heat exchanging part 50 a is interposed in the middle of the return refrigerant pipe 6 connected to the outlet side connection refrigerant pipe 31 of the hot water supply tank 3. The heat receiving side heat exchanging part 50 b is interposed on the upstream side of the expansion valve 52 of the bypass pipe 51.

  In the present embodiment, the refrigerator-side controller 25 functions to control the opening degree of the expansion valve 52 and the opening / closing of the bypass valve 53 upstream of the auxiliary heat exchanger 50 in addition to the control function in the first embodiment. The bypass control means is provided.

  The bypass control means assists the liquid refrigerant discharged from the refrigerator main body 7 when the operation on the showcase 10, 10,..., Unit cooler 28 side is stopped during the defrosting operation or to prevent overcooling. By detouring to the heat exchanger 50, heating with hot gas from the hot water supply tank 3 and then returning to the suction side of the compressor 12 again enables hot water supply. When the refrigerator 2 is used alone without connecting the hot water supply tank 3, when all the showcases 10, 10,... And the unit cooler 28 are stopped for defrosting operation or for preventing overcooling, etc. Since it is not necessary to operate any more, the compressor 12 is stopped. On the other hand, when the hot water supply tank 3 is connected and all the showcases 10, 10,..., The unit cooler 28 are stopped, the bypass control means operates using the auxiliary heat exchanger 50 in order to continue the hot water supply. Take control.

  FIG. 9 is a flowchart showing a control method of the bypass control means. As shown in FIG. 9, in S31, the bypass control means first detects the low-pressure side pressure detection value Pcs detected by the low-pressure side pressure sensor 20 on the refrigerator body 7 side lower than the low-pressure side pressure set value Pst (Pcs <Pst ) Or not.

  The low pressure side pressure set value Pst is such that the refrigeration load side such as the showcase 10, 10,... The pressure is set to a low low pressure side that occurs when operating. In the independent operation of the refrigerator 2 not connected to the hot water supply tank 3, the compressor 12 is stopped when this pressure drop is detected. In the defrosting operation on the refrigeration load side of the showcase 10, etc., the stop valve 29 is closed and the cooling operation is stopped, and the defrosting operation is heated by the room temperature in the room where the showcases 10, 10,. Defrosted.

  Since the low pressure side pressure detection value Pcs is the same and higher than the set value Pst (Pcs> Pst), if Pcs <Pst does not hold in S31, the result is No, and one of the showcases 10, 10,. Since 28 and the like are operating, the operation of the compressor 12 of the refrigerator main body 7 is continued in the next S32.

  On the other hand, in the case of Yes in S31, that is, when Pcs <Pst is established, the operation on the refrigeration load side of the showcases 10, 10,... It is determined that the flow rate of the gas refrigerant returning to the side has decreased and the low-pressure side pressure detection value Pcs has decreased below the set value Pst, and the process proceeds to the next S33. In the independent operation of the refrigerator 2 that does not connect the hot water supply tank 3 as described above, the compressor 12 is stopped when this state is detected, but the bypass control means is the hot water supply temperature on the hot water supply tank 3 side in the next S33. It is determined whether or not the hot water temperature detection value Tk of the sensor 34 exceeds the set value Ts (for example, 65 ° C.) (Tk> Ts).

  Since the hot water supply temperature setting value Ts is set to a hot water supply possible temperature, when Tk> Ts is established, hot water can be supplied by hot water storage in the hot water supply tank 3 even if the operation of the compressor 12 is stopped. In S34, the operation of the compressor 12 is stopped. Thereafter, the process returns to S31 again, and the steps after S31 are repeated.

  On the other hand, in the case of No in S33, that is, when the hot water supply temperature detection value Tk does not exceed the set value Ts, since the hot water in the hot water supply tank 3 is low temperature, sufficient hot water supply cannot be performed, so the compressor 12 is stopped. Instead, in the next S35, the bypass valve 53 of the normally closed solenoid valve is opened.

  Then, the liquid refrigerant from the refrigerator main body 7 is guided to the bypass valve 53 being opened, and flows into the bypass pipe 51. On the other hand, the flow into the showcase 10, 10,..., The unit cooler 28 is still blocked by the stop valve 29 being closed.

  The liquid refrigerant branched into the bypass pipe 51 is decompressed by the expansion valve 52 and then passes through the heat receiving side heat exchanging part 50b of the auxiliary heat exchanger 50. At this time, since the hot gas from the outlet connection refrigerant pipe 31 of the hot water supply tank 3 passes through the remaining heat side heat exchanging part 50a of the auxiliary heat exchanger 50, the heat receiving side heat exchanging part 50b is caused by this hot gas. It is heated and absorbs heat (receives heat) as if it was evaporated by an evaporator such as the showcase 10 and returned to the suction side of the compressor 12 again.

  For this reason, the refrigerant does not stay and circulates in the refrigeration cycle using the auxiliary heat exchanger 50 as an evaporator and the operation of the compressor 12 continues without stopping, so that hot gas is continuously supplied to the hot water supply tank 3 side. In addition, heating of the stored water (hot water storage) can be continued.

  Thereafter, the time Tm when the bypass valve 53 is opened in the next S36 is measured by a clock (not shown) built in the refrigerator-side controller 25, and the valve opening time exceeds a predetermined set value Ts (for example, 10 minutes). It is repeatedly determined whether or not (Tm> Ts). This is because the refrigerator-side controller 25 detects whether or not the operation on the refrigeration load side of the showcase 10, 10,. That is, in a state where the bypass valve 53 is opened, the low pressure side pressure detection value Pcs is such that the refrigerant flows through the bypass valve 53 and the auxiliary heat exchanger 50, so that the refrigeration load side such as the showcase 10, 10,. That is, in order to cope with the problem that the low pressure does not change even if any one of the stop valves 29 is opened. The valve opening time set value Ts may be an arbitrary time, and may be shorter or longer than 10 minutes, for example.

  In S36, if Yes, that is, if Tm> Ts is established, the bypass valve 53 is closed in S37, and the flow of the refrigerant to the bypass valve 53 and the auxiliary heat exchanger 50 is stopped. Thereafter, the process returns to S31 again. Here, when the refrigeration load side of the showcases 10, 10,... Is still stopped, the low-pressure-side pressure detection value Pcs on the refrigerator body 7 side is lower than the set value Pst (Pcs). <Pst), so the control from S31 is repeated again. Since the refrigerant pressure does not change immediately, it is necessary to provide a slight time interval (about 30 seconds) in order to shift from the closing of the bypass valve 53 in S37 to the pressure determination in S31.

  On the other hand, when the refrigeration load side such as the showcase 10, 10,... Resumes operation, Pcs <Pst in S31 is not established, and the normal compressor 12 in the state where the bypass valve 53 is closed in S32 again. Driving continues.

  Thus, even when the cooling operation on the refrigeration load side of the showcase 10 or the like is stopped, the auxiliary heat exchanger 50 heats and evaporates the liquid refrigerant instead of the refrigeration load side evaporator of the showcase 10 or the like. Therefore, the compressor 12 can be continuously operated. For this reason, hot gas can be continuously supplied from the compressor 12 to the hot water supply tank 3 side. Therefore, even when the cooling operation on the refrigeration load side of the showcase 10 or the like is stopped, the hot water supply range can be expanded.

(Third embodiment)
FIG. 10 is a configuration diagram mainly showing a refrigeration cycle of a refrigeration apparatus 1B according to the third embodiment of the present invention.

  As shown in FIG. 10, the refrigeration apparatus 1B performs bidirectional communication with a refrigerator-side controller 25B in the refrigerator 2B via a signal line 60 on the load-side controller 61 on the refrigeration load side such as the showcase 10 or the like. The two controllers 25B and 61 are connected to each other and communicate with each other to operate the refrigerator main body 7 side and, for example, four showcases 10a, 10b, 10c, and 10d, which are refrigeration and cooling loads, respectively. Control. That is, in the first and second embodiments, the refrigeration load side of the showcase 10 and the like and the refrigerator are operated independently, but in this embodiment, the refrigerator side controller and the load side controller 61 are operated. In cooperation with each other, by controlling the entire system including the refrigeration load side, the hot water supply operation can be carried out efficiently while achieving both the operation on the refrigeration load side and the hot water supply operation. Hereinafter, the cooling or refrigeration load includes the unit cooler 28 shown in FIGS. 1 and 8 and other cooling loads.

  The refrigerator main body 7 is provided in the suction side gas temperature sensor 62 attached to the suction pipe of the compressor 12 and the refrigerant pipe 14 on the high pressure side between the condenser 13 and the compressor 12, and the high pressure side pressure has reached a predetermined value. A high pressure switch 63 that sometimes stops the operation of the compressor 12, a receiver tank 64 that is provided in the suction side piping of the compressor 12, stores liquid refrigerant, and an accumulator 65 that is provided on the suction side of the compressor 12. Yes.

  The cooling (freezing) load side has a plurality of, for example, first (# 1) to fourth (# 4) four showcases 10a, 10b, 10c, and 10d. In each housing 66a, 66b, 66c, 66d, evaporators 67a, 67b, 67c, 67d, for example, load side expansion valves 68a, 68b, 68c, 68d made of PMV, stop valves 29a, 29b, 29c which are on-off valves. , 29d and one or a plurality of evaporator fans 69a, 69b, 69c, 69d for blowing air to the evaporators 67a to 67d, and a load for detecting the temperature in the showcases 10a to 10d cooled by the evaporators 67a to 67d Side suction temperature sensors 70a, 70b, 70c, and 70d are incorporated.

  In the showcases 10a to 10d, liquid refrigerant inlet pipes 71a, 71b, 71c, and 71d are connected to the liquid refrigerant inlet sides of the evaporators 67a to 67d, respectively, and in the middle of the liquid refrigerant inlet pipes 71a to 71d. The first to fourth stop valves 29a to 29d and the load expansion valves 68a to 68d including the PMV (pulse step motor valve) are respectively interposed.

  These liquid refrigerant inlet pipes 71a to 71d are connected to each other by a liquid side collecting pipe 72 and are connected to a liquid side refrigerant pipe 8 extending from the refrigerator 2B.

  Further, each of the evaporators 67a to 67d is connected to the gas refrigerant outlet pipes 73a, 73b, 73c, and 73d on the gas refrigerant outlet side, and the gas refrigerant outlet pipes 73a to 73d are connected to the gas side collecting pipe 74, respectively. After being connected so as to gather together, the gas side refrigerant pipe 9 is connected. Accordingly, the evaporators 67a to 67d of the showcases 10a to 10d are connected in parallel to the liquid side refrigerant pipe 8 and the gas side refrigerant pipe 9.

  The refrigerator-side controller 25B has the same function as the refrigerator-side controller 25 shown in FIGS. 1 and 8, and also has a communication function capable of bidirectional data communication with the load-side controller 61. The load-side controller 61 is composed of, for example, a microprocessor, as with the refrigerator-side controller 25B, and stores a control program indicating various control methods, a CPU that sequentially reads and executes control program instructions from the ROM, It has a RAM that forms a work area for execution, and has a function of performing bidirectional data communication with the refrigerator-side controller 25B. The load-side controller 61 is connected to each showcase 10a to 10d, and controls the operation of each showcase 10a to 10d in cooperation with the refrigerator side controller 25B. The load side controller 61 also receives the inlet temperature and outlet temperature of the evaporators 67a to 67d of the showcases 10a to 10d (not shown).

  The load-side controller 61 receives various data from the refrigerator-side controller 25B and controls the hot water supply to be continued by continuing the operation of the compressor 12 as much as possible when hot water supply is started. It has various control means. Next, these control methods will be described with reference to FIGS. 11 to 16, the loads # 1 to # 4 indicate the first to fourth showcases 10a to 10d.

  As shown in FIG. 11, first in S61, the load-side controller 61 receives a signal indicating that the refrigerator 2 is in operation from the refrigerator controller 25B via the signal line 60, and further receives the next S62. In the same manner, a signal indicating that the hot water supply operation has started is received.

  Thereafter, in S63, the load-side controller 61 allows the intake gas temperature detection value Tcin of the compressor 12 to be hot water supply after the required time (for example, a minute) during which the pressure of each part is stabilized from the start of the operation of the refrigerator 2. It is determined whether or not threshold A (Tcin> A) is established. When the suction gas temperature of the compressor 12 is lowered, the discharge hot gas temperature is also lowered, and there is a case where the hot gas temperature at which hot water can be supplied cannot be secured. The suction gas temperature detection value Tcin is detected by the suction side gas temperature sensor 62 and is given to the load side controller 61 through communication with the refrigerator side controller 25B. The threshold A for hot water supply is set to a lower limit value that can secure a hot gas temperature capable of heating the stored water (hot water storage) in the hot water tank 3.

  If Tcin> A is established in S63, that is, if Yes, in the next S64, the load-side controller 61 sets the opening degree of the load expansion valves 68a to 68d of the showcases 10a to 10d to the current opening. Hold it every time and continue driving.

  Then, in the next S65, when the hot water supply operation is completed, the process returns to S61 again, and a loop process is repeated to repeat the processes of the steps after S61. In the second and subsequent S63, the time delay of the refrigeration cycle state change with respect to the operation change is taken into consideration, and each time this step is executed, the determination is executed after the required time has elapsed.

  On the other hand, if No in S63, that is, if Tcin> A is not established, the process branches to the next S66 to S69, and the targets of the first to fourth (# 1 to # 4) showcases 10a to 10d are obtained. The degree of heating is increased by a predetermined value (n ° C.). The target heating degree indicates a difference (° C.) between the inlet temperature and the outlet temperature of the evaporators 67a to 67d of each showcase 10a to 10d.

  Thereafter, in S70 to S73, control is performed to reduce the opening degree of the first to fourth (# 1 to # 4) load expansion valves 68a to 68d so as to reach the respective target heating degrees. Thereafter, the process returns to S63 again, and a loop process for repeating the processes after S63 is performed.

  As a result of this loop processing, the suction gas temperature Tcin on the refrigerator 2 side increases. As a result of the increase in the suction gas temperature Tcin, when Tcin> A is established exceeding the threshold A which is a lower limit value capable of securing a hot gas temperature capable of supplying hot water, the process proceeds to S64 and the load for each showcase 10a to 10d is reached. The opening degree of the expansion valves 68a to 68d is maintained in the state at that time.

  As a result, the hot gas supplied to the hot water supply heat exchanger 4 in the hot water supply tank 3 is maintained at or above the lower limit of the hot water supply temperature at which hot water can be supplied, so that the hot water supply operation can be continued.

  Subsequently, while the operation of the compressor 12 is stopped according to the operation of the low pressure switch that operates at a low pressure determined based on the set temperature of the showcase on the load side, the pressure setting value at which the low pressure switch operates A control method for continuing the hot water supply operation by continuing the operation without stopping the compressor 12 as much as possible will be described.

  In the flowchart shown in FIG. 12, the low pressure switch is operated at the set pressure PLS set based on the set temperature of the load-side showcase to stop the operation of the compressor 12, but up to the set pressure at which the low pressure switch operates. Even when the low-pressure side pressure of the compressor 12 is lowered, if there is a margin in the safe operation range of the refrigeration cycle equipment, a control method for reducing the set pressure PLS at which the low-pressure switch operates to its set lower limit value is added. . In addition, the setting lower limit value of the low pressure switch means a minimum pressure at which the operation can be continued without failure of the refrigeration cycle components, mainly the compressor.

  In FIG. 12, circles A and B indicate connectors in the flowchart, circle A is connected to circle A in the flowchart shown in FIG. 13, and circle B is connected to circle B in the flowchart shown in FIG.

  That is, generally, when the temperature of the showcases 10a to 10d drops below the set temperature, the stop valves 29a to 29d on the showcases 10a to 10d side are closed, and the operation on the load side is stopped. When all of the stop valves 29a to 29d are closed, the return flow rate of the refrigerant returning from the showcases 10a to 10d to the compressor 12 decreases, so the pressure on the low pressure side decreases, and the low pressure switch of the refrigerator main body 7 The operation of the compressor 12 is stopped. When the operation of the compressor 12 is stopped, the hot gas supplied from the compressor 12 to the hot water supply tank 3 is stopped, so that hot water cannot be supplied. Accordingly, a control method for reducing the set value at which the low pressure switch operates to the set lower limit value and continuing the operation of the showcases 10a to 10d, but making it difficult for the internal temperature to greatly decrease from the set temperature is shown in FIG. Adding to the method.

  First, in S81, the load-side controller 61 receives a signal indicating that the refrigerator 2 is in operation from the refrigerator-side controller 25B via the signal line 60, and further starts hot water supply in the next S82. The signal which shows having carried out is received from the refrigerator side controller 25B. Here, the start of hot water supply means that the hot water supply tank 3 is connected to the refrigerator 2B, and “connection” is set by the connection state manual setting device 26 or the connection state determination means described above. Alternatively, when it is determined as “connected”, the refrigerator-side controller 25B notifies the fact. When the hot water supply tank 3 is not connected, a signal indicating that hot water supply is started is not output from the refrigerator-side controller 25B, and hence the subsequent control is not executed.

  Thereafter, in S83, it is repeatedly determined whether or not the low pressure side pressure detection value PL detected by the low pressure side pressure sensor 20 on the refrigerator 2B side is lower than the set value PLS (PL <PLS). That is, when PL <PLS is established, the low pressure side pressure set value PLS is forcibly lowered to the set lower limit value.

  Then, after the required time a minutes when the pressure in each part of the refrigerator 2 is stabilized, the process branches to S85 to S88 shown in FIGS. 13 and 14 connected by the connector circles A and B, respectively. The load side suction temperature detection values Tin detected by the load side suction temperature sensors 70a to 70d of the first to fourth (# 1 to # 4) showcases 10a to 10d are stored in the respective showcases 10a to 10d. It is determined whether or not the temperature is equal to or higher than the internal set temperature Tins (Tin ≧ Tins).

  No in S85 to S88, that is, when Tin ≧ Tins is not established, each target heating degree is increased by a predetermined value (+ n ° C.) in the next S89 to S92, and further, in the next S93 to S96, the target heating degree The degree of opening of each of the load side expansion valves 68a to 68d is controlled so that Conventionally, when Tin <Tins, the stop valves 29a to 29d on the showcase 10a to 10d side were immediately closed, but in this control, the stop valves 29a to 29d are not closed and the load side is closed. The opening degree of the expansion valves 68a to 68d is narrowed down, and the cooling capacity is reduced by reducing the amount of refrigerant flowing through the evaporators in the showcases 10a to 10d. Driving can be continued. However, as a result of continuing to throttle the opening of the load side expansion valves 68a to 68d, when the low pressure decreases to the lower limit value of the pressure switch, the pressure switch operates to compress the refrigeration cycle equipment to protect it. The machine 12 will be stopped.

  Thereafter, in S85 to S88, whether the suction temperature Tin on the load side of the first to fourth (# 1 to # 4) has reached the interior set temperature Tins of the showcases 10a to 10d (Tin ≧ Tins) or not. It is judged again, and when Tin ≧ Tins is established, the operation of the load side expansion valves 68a to 68d is continued at the current opening degree in S97 to S100. Returning to the first S81 again, the steps after S81 are repeated. The expansion valve control shown in FIGS. 11, 13, and 14 has been described with an example of four showcases 10 a to 10 d connected to the load side, but in other cases, the number of showcases to be connected is It is necessary to add or delete steps according to the increase or decrease.

  The control by the load-side controller 61 shown in FIG. 15 shows a control method for continuing the operation of the compressor 12 while increasing the operation frequency of the compressor 12 in order to shorten the boiling time of the hot water supply. In FIG. 15, connector circles A and B are connected to the flowcharts of connector circles A and B shown in FIGS.

  That is, when the operating frequency of the compressor 12 is increased in order to shorten the boiling time of the hot water supply, the rotational speed of the compressor 12 is increased, the refrigerant flow rate circulating in the refrigeration apparatus 1B is increased, and the hot water supply tank 3 side is increased. Since the flow rate of the hot gas supplied increases, the boiling time of hot water supply can be shortened.

  On the other hand, on the showcases 10a to 10d side, the evaporation temperature of the evaporators 67a to 67d is lowered and the cooling temperature is lowered, so that the internal temperature is lowered. For this reason, since the low-pressure side pressure on the refrigerator main body 7 side decreases, when the low-pressure side pressure decreases to the operating pressure of the low-pressure switch, the operation of the compressor 12 is forcibly stopped and hot water supply is also stopped. As in the above description, the operating pressure of the low pressure switch is set to a low value in accordance with the cooling set temperature (for example, −5 ° C. to −20 ° C.) of the showcases 10a to 10d.

  For this purpose, the load-side controller 61 is controlled by the control method shown in FIG. That is, the load-side controller 61 first sets the operation frequency of the compressor 12 accompanying the refrigerator operation signal, the hot water supply operation start signal, and the hot water supply operation from the refrigerator side controller 25B to the required Hz (+ DHz) in S111, S112, and S113. A signal indicating that the signal has been raised is received. S111 and S112 are the same as S81 and S82 described above.

  Since the operating frequency of the compressor 12 is increasing, the boiling time of the hot water supply is shortened as described above, while the cooling effect on the refrigeration load side of the showcases 10a to 10d is increased and the internal temperature is gradually cooled. Approaches the set value. For this reason, the opening degree of the load side expansion valves 68a to 68d is reduced. For this reason, since the refrigerant | coolant flow rate which returns to the suction side of the compressor 12 decreases, the low-pressure side pressure on the suction side decreases.

  Therefore, in the next S114, a loop process for repeatedly determining whether or not the low pressure side pressure detection value PL detected by the low pressure side pressure sensor 20 on the refrigerator body 7 side is lower than the set value PLS (PL <PLS). In the case of Yes, that is, when PL <PLS is established, in the next S115, the low pressure side pressure set value PLS is forcibly lowered to the set lower limit value. Accordingly, it is possible to prevent the operation of the compressor 12 from being stopped as much as possible by the operation of the low pressure switch, and to continue the operation. Since the steps after S115 control the opening degree of the load side expansion valves 68a to 68d of the showcases 10a to 10d in the same manner as the steps S85 to S101 of the steps shown in FIG. 13 and FIG. A description thereof will be omitted.

  In the flowchart shown in FIG. 16, the operation of the compressor 12 is continued without stopping as much as possible even when the first to fourth (# 1 to # 4) showcases 10a to 10d are defrosted. The control method by the load side controller 61 is shown.

  That is, when a request for a defrosting operation is issued from all of the connected showcases 10a to 10d, the load-side controller 61, first, in S121 and S122, as shown in FIG. After sequentially receiving the operation start signal from the refrigeration side controller 25B, a signal for permitting the defrosting operation of the first (# 1) and second (# 2) showcases 10a and 10b in the next S123 and S124. Are sequentially output, the stop valves 29a and 29b of the first (# 1) and second (# 2) showcases 10a and 10b are sequentially closed, and the defrosting operation is sequentially started. For this reason, since the refrigerant | coolant flow rate returned to the compressor 12 side of the refrigerator main body 7 from the showcases 10a-10d side reduces, the pressure of the low pressure side of the compressor 12 falls.

  Therefore, in the next S125, the low pressure side detected by the low pressure side pressure sensor 20 on the refrigerator main body 7 side after the required time (a second) during which the pressure in each part of the refrigeration cycle is stabilized after the operation of the refrigerator 2 is started. It is determined whether or not the pressure detection value PL is higher than the low-pressure side pressure set value PLS (PL> PLS), No, that is, the low-pressure side pressure detection value PL is lower than the set value PLS (PL <PLS). When it is determined that the operation of the compressor 12 may be stopped by the operation of the low pressure switch, the defrosting operation of the first and second showcases 10a and 10b is shifted without simultaneously. That is, in S126, the showcase 10b, which is the load of the second (# 2) showcase 10b, is continuously cooled without starting the defrosting operation until the defrosting operation of the first showcase 10a is completed. In order to continue the operation, the stop valve 29b of the second showcase 10b is opened to return to the cooling operation. Therefore, only the showcase 10a which is the first (# 1) load starts the defrosting operation, and the other showcases 10b to 10d continue the cooling operation. In the defrosting operation, the cooling operation is stopped, the defrosting is performed by the temperature (room temperature) in the room where the showcases 10a to 10d are installed, and the defrosting time is set by a timer.

  When the defrosting operation of the first (# 1) showcase 10a is ended by the timer in S127, the process returns to S124 again, the defrosting operation permission of the second showcase 10b is output, and the stop valve 29b is closed. And start the defrosting operation. Next, in S125, it is determined again whether PL> PLS is satisfied. In this case, since the defrosting operation is performed for only one of the second showcases 10b, the low pressure side pressure detection value PL is low. The pressure is higher than the side pressure set value PLS (PL> PLS). Therefore, when the determination in S125 is established (YES), the low-pressure-side pressure detection value PL is the same and higher than the set value PLS, and the operation of the compressor 12 is not stopped. The defrosting operation start of the (# 3) showcase 10c is permitted, the stop valve 29c of the third (# 3) showcase 10c is closed, and the defrosting operation of the third (# 3) showcase 10c is closed. To start.

  On the other hand, even if the simultaneous defrosting operation is performed on both the first (# 1) showcase 10a and the second (# 2) showcase 10b in S123 and S124, the low pressure side pressure detection value PL is low on the low pressure side in S125. Also when the pressure is higher than the pressure set value PLS (PL> PLS), the process proceeds to S128, the stop valve 29c of the third (# 3) showcase 10c is closed, and the third (# 3) showcase 10c. The defrosting operation is started.

  Since the simultaneous defrosting operation of the first to third showcases 10a to 10c or the simultaneous defrosting operation of the second and third showcases 10b and 10c reduces the low pressure side pressure PL on the compressor 12 side, In S129, it is determined whether or not PL> PLS is satisfied again after the required time (a seconds) has elapsed since the start of the defrosting operation of the third (# 3) showcase 10c. In S129, in the case of No, that is, when it is determined that PL> PLS is not established, the defrosting of the showcase currently in the defrosting operation or the first or second showcase 10a, 10b is performed. Since the defrosting operation of the third (# 3) showcase 10c is interrupted until the operation is completed, the stop valve 29c of the third (# 3) showcase 10c is opened in S130 to perform the cooling operation. return.

  Thereafter, in S131, when the defrosting operation of one of the defrosting showcases, for example, the second (# 2) showcase 10b is completed, the process returns to S128 again, where the third showcase is displayed. The defrosting operation of 10c is permitted, and the stop valve 29c is closed.

  In S129 again, after starting the defrosting operation of the third showcase 10c, it is determined whether or not PL> PLS is satisfied after a required a seconds have elapsed. Here, in the case of Yes, that is, when PL> PLS is established, until one of the first to third showcases 10a to 10c during the defrosting operation ends the defrosting operation in the next S132, The fourth showcase 10d continues the cooling operation. In addition, when it transfers to S129 via S131, since at least 1 unit | set of the showcase which was performing the defrost operation has transferred to cooling operation, PL> PLS is materialized in S129.

  After that, in S133, it is repeatedly determined whether or not the defrosting operation of any of the first to third showcases 10a to 10c has been completed. When the answer is Yes, in the next S134, the fourth (# 4 The defrosting operation permission of the showcase 10d is output, and the stop valve 29d of the fourth showcase 10d is closed.

  Subsequently, in S135, after the required time (for example, several seconds) elapses, whether or not the low pressure side pressure detection value PL detected by the low pressure side pressure sensor 20 of the compressor 12 is higher than the set value PLS (PL> PLS). If NO is determined, that is, if PL> PLS is not established, the low pressure side pressure detection value PL may be lower than the operating pressure of the low pressure switch, and the operation of the compressor 12 may be forcibly stopped.

  Therefore, in order to avoid the operation stop of the compressor 12, in the next S136, the stop valve 29d of the fourth showcase 10d is opened again, the defrosting operation is interrupted, and the cooling operation is returned to. Thereby, the low pressure side pressure PL rises.

  Next, in S137, the defrosting operation is terminated when the defrosting time of one of the showcases in the defrosting operation so far, for example, the third showcase 10c, is up. Thereafter, again in S134, the stop valve 29d of the fourth showcase 10d is closed to start the defrosting operation.

  Thereafter, again in S135, after the required time (a second) has elapsed since the start of the defrosting operation, it is determined whether or not PL> PLS is satisfied. If YES, that is, if PL> PLS is satisfied, the process proceeds to S138. .

  In this S138, the first to the second showcase 10b to 10d, excluding the first showcase 10a that has already finished the defrosting operation, is returned to the cooling operation from the one that has completed the defrosting operation. All the showcases 10b to 10d complete the defrosting operation.

  As described above, in the flowchart shown in FIG. 16, a maximum of three showcases are simultaneously defrosted in a range where the low pressure side pressure PL does not fall below the set value PLS. Moreover, even if the request | requirement of a defrost operation comes out from all the showcases 10a-10d, at least 1 showcase always performs a cooling operation. As a result, since the operation of the refrigerator 2B can be continued within a range where the low pressure side pressure PL does not fall below the set value PLS, the hot water supply operation can be continued.

  Therefore, according to this defrosting operation method, the defrosting operation of the showcases 10a to 10d, which are a plurality of loads, can be sequentially performed while avoiding the operation stop of the compressor 12 as much as possible. For this reason, hot water can be supplied even during the defrosting operation of the showcases 10a to 10d.

  According to this refrigeration apparatus, when the short-circuit tube 24 is attached to the pair of refrigerant take-out parts 22 and the refrigerant return part 23 of the refrigerator main body 7, the refrigeration apparatus can be used exclusively for the refrigerator 2. it can.

  As described above, the refrigerator 2 of the present embodiment is used as a normal refrigerator by operating with the short-circuit tube 24 attached from the pair of refrigerant take-out portions 22 and the refrigerant return portions 23 of the refrigerator main body 7. In addition, by removing the short-circuit tube 24 and connecting the refrigerant supply section 5 and the return refrigerant pipe 6 on the hot water supply side to the refrigerant extraction section 22 and the refrigerant return section 23, the refrigerator 2 is used for hot water supply. Can also be used.

  As mentioned above, although several embodiment of this invention was described, these embodiment is shown as an example and is not intending limiting the range of invention. These novel embodiments can be implemented in various other forms, and various omissions, substitutions, and changes can be made without departing from the scope of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalents thereof.

  DESCRIPTION OF SYMBOLS 1,1A, 1B ... Refrigeration apparatus, 2, 2B ... Refrigerator, 3 ... Hot water supply tank, 4 ... Heat exchanger for hot water supply, 5 ... Refrigerant piping for extraction, 6 ... Refrigerant piping for return, 7 ... Refrigerator main body, 8 DESCRIPTION OF SYMBOLS ... Liquid side refrigerant | coolant piping, 9 ... Gas side refrigerant | coolant piping, 10 ... Showcase, 10a-10d ... 1st-4th showcase, 12 ... Compressor, 13 ... Condenser, 14 ... Refrigerant piping, 15 ... Gas refrigerant Inlet, 16 ... liquid refrigerant outlet, 17 ... fan, 18 ... discharge temperature sensor, 19 ... condenser inlet temperature sensor, 20 ... low pressure side pressure sensor, 22 ... refrigerant outlet, 23 ... refrigerant return, 24 ... short circuit, 25, 25B ... refrigerator side controller, 26 ... connection state manual setting device, 27 ... heat exchanger, 29 ... stop valve, 32, 33 ... half union, 34 ... temperature sensor for hot water supply, 50 ... auxiliary heat exchanger, 51 ... Bypass piping, 52 ... Expansion valve, 5 ... Bypass valve, 60 ... Signal line, 61 ... Load side controller, 62 ... Suction side gas temperature sensor, 67a, 67b, 67c, 67d ... Evaporator, 68a, 68b, 68c, 68d ... Expansion valve for load, 70a, 70b, 70c, 70d... Load side suction temperature sensor.

Claims (5)

The compressor and the condenser are connected by a refrigerant pipe, the load side expansion valve and the evaporator can be connected by a refrigerant pipe, and the refrigerant pipe between the refrigerant discharge side of the compressor and the condenser, Refrigerant take-out section for taking out hot gas refrigerant to be supplied to a hot water supply heat exchanger for heating water in the hot water supply tank, and refrigerant return section for returning hot gas refrigerant taken out from the refrigerant take-out section to the condenser side And a short-circuit tube that is detachably attached to the refrigerant take-out part and the return part and directly connects them. A refrigerant take-out unit that sequentially connects a compressor, a condenser, a load-side expansion valve, and an evaporator with a refrigerant pipe, and takes out hot gas refrigerant into a refrigerant pipe between the refrigerant discharge side of the compressor and the condenser; A hot water supply heat exchanger that is connected to the refrigerant take-out part and the return part and passes the hot gas refrigerant from the compressor, while providing a refrigerant return part that returns the hot gas refrigerant taken out from the refrigerant take-out part to the condenser, In the refrigeration apparatus provided with a hot water supply tank capable of supplying hot water for storing water to be heat exchanged with this hot water heat exchanger,
A high pressure side pressure sensor for detecting the pressure on the high pressure side of the compressor;
The high pressure side pressure detection value detected by the high pressure side pressure sensor is not reduced below the high pressure side pressure set value set to maintain the lower limit temperature at which the hot water supply tank can supply hot water. Fan rotation speed control means for controlling the rotation speed;
A refrigeration apparatus comprising: A refrigerant that sequentially connects a compressor, a condenser, a load-side expansion valve, and a load-side evaporator through a refrigerant pipe, and extracts hot gas refrigerant into a refrigerant pipe between the refrigerant discharge side of the compressor and the condenser. A hot water supply heat that is connected to the refrigerant take-out part and the return part and passes the hot gas refrigerant from the compressor while providing a take-out part and a refrigerant return part that returns the hot gas refrigerant taken out from the refrigerant take-out part to the condenser In the refrigeration apparatus including a hot water supply tank capable of supplying hot water for storing water to be heat exchanged with the exchanger and the heat exchanger for hot water supply,
A hot water supply temperature sensor that detects the temperature of a return refrigerant pipe through which the refrigerant returned from the hot water supply heat exchanger to the refrigerant return portion side passes;
A bypass pipe connecting between the liquid side refrigerant pipe and the gas side refrigerant pipe to which the evaporator is connected;
An auxiliary heat exchanger for exchanging heat between the liquid refrigerant from the liquid side pipe that is interposed in the middle of the bypass pipe and connected to the condenser, and the refrigerant from the heat exchanger for hot water supply,
A normally closed bypass valve interposed in the middle of the bypass pipe;
An expansion valve interposed between the bypass valve and the auxiliary heat exchanger;
A low-pressure side pressure sensor for detecting a low-pressure side pressure of the compressor;
The low pressure side pressure detection value detected by the low pressure side pressure sensor is lower than the low pressure side pressure set value when the operation of the evaporator is stopped, and the hot water supply temperature detection value detected by the hot water supply temperature sensor is the hot water supply temperature. When the temperature of the stored water is higher than the hot water supply temperature set value, the operation of the compressor is stopped, and the low pressure side pressure detection value detected by the low pressure side pressure sensor is the low pressure side pressure set value for operation stop. And a bypass on-off valve control means for opening the bypass on-off valve for a predetermined time and continuing the operation of the compressor when the hot water supply temperature detection value is lower than the hot water supply temperature set value,
A refrigeration apparatus comprising the refrigeration apparatus. The refrigerator according to claim 1, wherein the short-circuit tube has a length of 10 to 25 cm. A discharge temperature sensor for detecting a discharge temperature of the compressor;
A condenser inlet temperature sensor for detecting the inlet temperature of the condenser;
Depending on the discharge temperature detection value detected by the discharge temperature sensor and the condenser inlet temperature detection value detected by the condenser inlet temperature sensor, the short-circuit tube or the hot water supply is connected to the refrigerant take-out portion and the return portion, respectively. A connection state determining means for determining which of the heat exchangers is connected,
The refrigerator according to claim 1 or 4, wherein the refrigerator is provided.

Images