JPH08266226A - Iced confectionery production machine - Google Patents

Abstract

PURPOSE: To provide an iced confectionery production machine so designed that the pressure of a chilling medium returning to a compressor is made constant by a constant pressure expansion valve, thereby enabling stable heat sterilization to be quickly operated without bringing the compressor to an overloaded state even if conditions such as ambient temperature are fluctuated. CONSTITUTION: This iced confectionery production machine has such a scheme that a vessel 1 and a cylinder 2 are heat-sterilized through such a cycle that a delivery gas chilling medium from a compressor 4 is circulated from a heat exchanger 5 for the vessel 1 and another heat exchanger 6 for the cylinder 2, via a 1st heat exchange piping 21a, a constant pressure expansion valve 24 and a 2nd heat exchange piping 21b successively in this order, to the compressor 4.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a frozen dessert making machine for producing frozen desserts such as ice cream and shakes, and more particularly to heating a container for storing raw materials for frozen desserts and a cylinder for producing frozen desserts for sterilization. The present invention relates to a frozen dessert making machine in which the discharge pressure of the compressor is properly maintained and a high-temperature and high-pressure refrigerant gas can be stably obtained without increasing the load of the compressor.

[0002]

2. Description of the Related Art Generally, a frozen dessert making machine for producing frozen desserts such as ice cream and shakes is provided with a container for storing raw materials for frozen desserts and a cylinder for producing frozen desserts by kneading the raw materials while freezing. The frozen dessert manufactured by such a frozen dessert making machine is required by law to be negative for coliform bacteria. For this reason, it is necessary to sterilize the container and the cylinder at least once a day, and the sterilization must be performed at a temperature of 68 ° C. for 30 minutes or by a method having an effect equal to or higher than this. I won't.

An apparatus for performing such heat sterilization by switching the cycle of the refrigerating apparatus is disclosed in, for example, Japanese Patent Laid-Open No. 6-906.
No. 70 publication. In the apparatus, as shown in FIG. 2, the discharge gas refrigerant from the compressor 54 passes from the four-way valve 57 through the main heat exchanger 65 and then expands for cooling as shown by a solid arrow in the figure. Vessels 68a and 68b,
A first circulation path is formed in which the four-way valve 57 returns to the compressor 54 through the container heat exchanger 55 and the cylinder heat exchanger 56 respectively provided in the container 51 and the cylinder 52. The devices are connected to each other.

In the operation of circulating the refrigerant through the first circulation path, the main heat exchanger 65 acts as a condenser, the container heat exchanger 55 and the cylinder heat exchanger 56 act as evaporators, respectively, and the container 51 And the cylinder 52 is cooled.

The device is further provided with an auxiliary heat exchanger 71 and a heating expansion device 74, and when the four-way valve 57 is switched from the above, a second circulation path shown by a broken line arrow in the drawing. The operation is switched to one in which the refrigerant circulates through. That is, in this operation, the discharge gas refrigerant from the compressor 54 flows from the four-way valve 57 into the container heat exchanger 55 and the cylinder heat exchanger 56, and then these heat exchangers 55.5.
After passing through the auxiliary heat exchanger 71 and the heating time expander 74 from 6, the flow is returned to the compressor 54.

In this operation, the gas refrigerant discharged from the compressor 54 is the heat exchanger 55 for containers and the heat exchanger 56 for cylinders.
Then, after the container 51 and the cylinder 52 are heated without being condensed, they flow into the auxiliary heat exchanger 71, and between the refrigerants that respectively flow in the first heat exchange pipe 71a and the second heat exchange pipe 71b. Condensates and evaporates due to the transfer of heat.

With this, the heat sterilization operation can be stably performed without imposing an overload on the compressor 54, and the condensation and evaporation of the refrigerant in this operation are performed by the first and second heat exchange operations. This is performed by exchanging heat between the refrigerants flowing through the pipes 71a and 71b, respectively, and it is not necessary to supply water, air or the like as a cold heat source or a heat source, so that it is possible to suppress a rise in operating costs.

Further, in the above device, the first to third pressure switches 85, 86 provided on the discharge pipe 58 of the compressor 54 are provided for the purpose of performing the heating operation more smoothly.
87, a bypass pipe 84 for returning a part of the refrigerant that has passed through the first heat exchange pipe 71a to the compressor 54 without passing through the heating time expander 74 and thereafter, and a bypass pipe 84 provided in the bypass pipe 84. An electromagnetic valve 82 and an electromagnetic valve 81 provided in a bypass pipe 72 that bypasses the heating expansion device 74 are provided.

The first pressure switch 85 outputs an ON signal when the discharge pressure of the compressor 54 exceeds a first set value (for example, 20 kg / cm ² ), and this signal causes the solenoid valve 82 to output.
Opens. Further, the second pressure switch 86 is used for the compressor 5
When the discharge pressure of No. 4 is the second set value (for example, 12 kg / cm ² ) or less, the ON signal is output, and the solenoid valve 81 is opened by this signal. Further, the third pressure switch 87 outputs an ON signal when detecting that the discharge pressure of the compressor 54 has risen abnormally, whereby the operation of the compressor 54 is stopped.

In this configuration, when the operation state of the apparatus is switched from the cooling operation to the heating operation, the discharge pressure of the compressor 54 is set to the second set value (for example, 12 kg) from the start of the heating operation. / Cm ² )
The solenoid valve 81 opens. As a result, the refrigerant bypasses the heating-time expander 74, so that the discharge pressure of the compressor 54 is increased.

Thereafter, when the discharge pressure further rises and reaches the first set value (for example, 20 kg / cm ² ) in the first pressure switch 85 by continuing the heating operation, the solenoid valve 81 is closed. The refrigerant having passed through the first heat exchange pipe 71a returns to the compressor 54 through the bypass pipe 84. As a result, the discharge pressure during the heating operation is maintained below the above first set value.

As described above, the first to third pressure switches 8
5.86.87, bypass pipe 72.84, solenoid valve 8
With the configuration including 1.82, it is possible to stabilize the discharge pressure during the heating operation.

[0013]

SUMMARY OF THE INVENTION However, the inventors of the present invention have the following problems when the ambient temperature or the temperature of the refrigerant is higher or lower than room temperature in the above-mentioned conventional apparatus. I found a problem.

That is, when a capillary tube is used as the expander 74 for heating, the capillary tube has a specification in which the refrigerant flowing into the capillary tube at the discharge pressure from the compressor 54 is reduced in pressure by reducing the resistance inside the tube. Therefore, for example, when the discharge pressure from the compressor 54 becomes higher than that at normal temperature due to high ambient temperature and refrigerant temperature such as in summer, the amount of liquid refrigerant passing through the capillary tube increases. The pressure of the refrigerant after passing through the capillary tube as the expander 74 for heating also becomes higher than that at room temperature, and as a result, the suction pressure of the compressor 54 becomes higher than that at room temperature. In such a case, there is a problem that the suction pressure of the compressor 54 may exceed the limit value specified in the specifications of the compressor 54 and the compressor 54 may be overloaded. There is.

Graphs a to c shown in FIG. 3 show changes in the discharge pressure of the compressor 54 from the time when the heating operation is started. In the same figure, a graph b shown by a solid line shows a change in the discharge pressure at a normal time, and a graph a shown by a dotted line is shown by a one-dot chain line when the ambient temperature and the refrigerant temperature are higher than those at the normal time such as in summer. Graph c
Indicates changes in the discharge pressure when the ambient temperature and the refrigerant temperature are lower than those in normal times such as in winter. As is clear from the figure, when the ambient temperature and the refrigerant temperature are lower than the normal temperature, the increase rate of the discharge pressure of the compressor 54 becomes slow, and the time required until the discharge pressure becomes stable increases. Have

The present invention has been made in view of the above-mentioned conventional problems, and an object thereof is a frozen dessert making machine capable of stably performing heat sterilization even if the ambient temperature or the refrigerant temperature changes. To provide.

[0017]

In order to achieve the above object, a frozen dessert making machine of the present invention comprises a container for storing ingredients of frozen dessert, a cylinder for producing the frozen dessert, and a compression for pressurizing and discharging a heat medium. Machine, a heat exchanger for a container and a heat exchanger for a cylinder that perform heat exchange between the heat medium and each of the container and the cylinder, and mutually so that heat exchange occurs between the heat mediums flowing inside. First and second arranged
A medium heat exchanger having a heat exchange pipe, and pressure adjusting means for decompressing the heat medium to a predetermined pressure within the set suction pressure range of the compressor and performing adiabatic expansion. The discharged heat medium is supplied from each of the container heat exchanger and the cylinder heat exchanger to the first heat exchange pipe of the medium heat exchanger, the pressure adjusting means, and the second heat exchange pipe of the medium heat exchanger. A frozen dessert making machine characterized in that the frozen dessert making machine is connected to each other by a pipe forming a medium circulation path for sequentially returning to the compressor after passing through.

[0018]

In the frozen dessert making machine having the above structure, the heat medium pressurized by the compressor and discharged as high-temperature gas heats the container heat exchanger and the cylinder heat exchanger, and It is condensed in the first heat exchange pipe, reduced in pressure to a predetermined pressure by the pressure adjusting means, adiabatically expanded, and further evaporated in the second heat exchange pipe of the medium heat exchanger and then returned to the compressor. In other words, the pressure of the heat medium returned to the compressor is set by the pressure adjusting means as an appropriate suction pressure range that does not overload the compressor, regardless of the pressure of the liquid medium at the time of inflow. The pressure is reduced to a predetermined pressure within the set suction pressure range set in. Therefore, it is possible to prevent the suction pressure of the compressor from fluctuating due to fluctuations in the ambient temperature and the temperature of the liquid medium itself, and it is possible to operate the compressor while always keeping the suction pressure appropriately. As a result, during heating operation to heat the container or cylinder above the sterilization temperature, even if conditions such as ambient temperature change, it is possible to prevent the load on the compressor from increasing and stabilize the suction pressure of the compressor. By doing so, the discharge pressure is also stabilized, so that the temperature of the container or the cylinder can be stably raised. In addition, for example, another heat exchanger may be added between the first heat exchange pipe and the pressure adjusting means in order to completely condense the heat medium.

Further, a bypass pipe for adjusting the suction pressure of the compressor, a switch for detecting the discharge pressure from the compressor and opening / closing a solenoid valve or the like provided on the bypass pipe according to the discharge pressure, etc. In comparison with the conventional configuration in which the heating element is provided, the control during heating operation can be simplified and the number of parts can be reduced, so that the apparatus can be downsized and the increase in manufacturing cost can be suppressed.

[0020]

EXAMPLE A frozen dessert making machine according to an example of the present invention will be described with reference to FIG. First, the basic circuit configuration of the freezing device provided in the frozen dessert making machine will be described with reference to FIG. This frozen dessert making machine is provided with a container 1 for storing frozen dessert raw materials, and a cylinder 2 for producing frozen desserts by kneading the raw materials supplied from the container 1 and freezing them. Therefore, the refrigeration system 3 is equipped.

The refrigerating apparatus 3 includes a compressor 4, a container heat exchanger 5 for exchanging heat between the container 1 and the refrigerant (heat medium), and a cylinder for exchanging heat between the cylinder 2 and the refrigerant. A four-way valve 7 for switching the flow direction of the discharged gas refrigerant from the heat exchanger 6 and the compressor 4 is provided.

The four-way valve 7 has an inflow port 9 to which a discharge pipe 8 of the compressor 4 is connected, an outflow port 11 to which a suction pipe 10 of the compressor 4 is connected, and a pair of first and second pairs. Switching ports 12 and 13 are provided. First switching port 1
The first gas pipe 14, the main heat exchanger 15, and the liquid pipe 16 are sequentially connected to 2, and the tip side of the liquid pipe 16 is the first liquid branch pipe 16
a, the second liquid branch pipe 16b, and the third liquid branch pipe 16c. The tip of the first liquid branch pipe 16a is connected to the container heat exchanger 5, and the tip of the second liquid branch pipe 16b is connected to the cylinder heat exchanger 6.

In the first liquid branch pipe 16a, the first solenoid valve 17a and the first capillary tube 18 are sequentially arranged from the liquid pipe 16 side.
a and the second solenoid valve 17 is installed in the second liquid branch pipe 16b.
b and the second capillary tube 18b are interposed in the same manner as above. The fifth solenoid valve 1 is attached to the third liquid branch pipe 16c.
7c and a constant pressure expansion valve 24, which will be described later, are provided in the same manner as above.

The suction pipe 10 is provided with an accumulator 19 for separating gas and liquid of the refrigerant. Further, a strainer 40 for removing dust and foreign matter mixed in the refrigerant is provided on the suction pipe 10 on the compressor 4 side of the accumulator 19. Further, a check valve 43 for preventing the reverse flow of the refrigerant to the four-way valve 7 is provided in the first gas pipe 14 described above.

On the other hand, the second switching port 13 of the four-way valve 7
A second gas pipe 20 is connected to. The tip end side of the second gas pipe 20 has a first gas branch pipe 20a and a second gas branch pipe 20a.
b, the tip of the first gas branch pipe 20a is connected to the container heat exchanger 5, and the second gas branch pipe 2
The end of 0b is connected to the cylinder heat exchanger 6.

The above refrigeration system 3 has an auxiliary heat exchanger 21.
(Medium heat exchanger) is further provided. In this auxiliary heat exchanger 21, two first and second heat exchange pipes 2 are provided.
1a and 21b are arranged side by side so that heat can be transferred between the refrigerants flowing in both pipes 21a and 21b.

At one end of the first heat exchange pipe 21a,
The first bypass pipe 22 is connected. The tip side of the first bypass pipe 22 has a third solenoid valve 23a and a fourth solenoid valve 2
3b is branched into a first bypass branch pipe 22a and a second bypass branch pipe 22b which are respectively interposed,
The tip of a is connected to a portion of the first liquid branch pipe 16a between the first capillary tube 18a and the container heat exchanger 5. The tip of the second bypass branch pipe 22b is connected to a portion of the second liquid branch pipe 16b between the second capillary tube 18b and the cylinder heat exchanger 6.

On the other hand, the other end of the first heat exchange pipe 21a is connected to the second bypass pipe 25.
Are connected to the first gas pipe 14. Also, this second
A check valve 44 for preventing the reverse flow of the refrigerant from the first gas pipe 14 is provided in the bypass pipe 25. Also,
One end of the second heat exchange pipe 21b has the third liquid branch pipe 16c.
The other end of the second heat exchange pipe 21b is connected to a portion of the suction pipe 10 between the four-way valve 7 and the accumulator 19 by the third bypass pipe 26.

In the above structure, the four-way valve 7 is positioned so that the inflow port 9 of the four-way valve 7 communicates with the first switching port 12 and the outflow port 11 of the four-way valve 7 communicates with the second switching port 13, respectively. 1 ・ Second solenoid valve 17a ・ 1
7b are opened, and the third and fourth solenoid valves 23a and 23a are opened.
By cooling the valves b and operating the compressor 4, the refrigerant circulates along the first circulation path indicated by the solid arrow in the drawing, and the container 1 and the cylinder 2 are cooled by the refrigerating device 3. Driving is performed. During this cooling operation, the first and second solenoid valves 17a and 17b are controlled to be opened and closed independently of each other, and the refrigerant flow through the respective liquid branch pipes 16a and 16b is intermittently controlled, so that the container 1 and the cylinder 2 are closed. Each set temperature is cooled and held. Further, during this cooling operation, the fifth solenoid valve 17c is closed.

In the above cooling operation, the high-temperature and high-pressure gas refrigerant discharged from the compressor 4 is guided to the main heat exchanger 15 through the discharge pipe 8, the four-way valve 7 and the first gas pipe 14. The main heat exchanger 15 has a heat exchange refrigerant pipe 1 inside.
The water heat exchanger 5a and the heat exchange water pipe 15b are arranged side by side. The heat exchange water pipe 15b is connected to a water pipe 38, and an on-off valve 39 that detects the pressure in the first gas pipe 14 and opens when the detected pressure exceeds a set pressure is provided in the water pipe 38. Has been done. As a result, heat is exchanged between the refrigerant and water flowing through both pipes 15a and 15b of the main heat exchanger 15, and the heat exchange refrigerant pipe 15a.
The refrigerant radiates heat to the heat exchange water pipe 15b and is condensed.

The liquid refrigerant condensed in the main heat exchanger 15 as described above is then split from the liquid pipe 16 into the first liquid branch pipe 16a and the second liquid branch pipe 16b. The liquid pipe 16 is provided with a dryer 41 for removing water in the refrigerant.
The liquid refrigerant split into the first and second liquid branch pipes 16a and 16b is
When passing through the first capillary tube 18a and the second capillary tube 18b, they undergo adiabatic expansion and change into a low-temperature low-pressure liquid refrigerant. Thereafter, the liquid refrigerant flows into the container heat exchanger 5 and the cylinder heat exchanger 6, respectively, and while passing through the heat exchangers 5 and 6, absorbs heat from the surroundings and evaporates. As a result, the container 1 and the cylinder 2 are cooled.

The low-temperature low-pressure gas refrigerant evaporated in the container heat exchanger 5 and the cylinder heat exchanger 6 is then passed through the first gas branch pipe 20a and the second gas branch pipe 20b to the second gas pipe 2.
It joins at 0, and is returned to the compressor 4 through the second gas pipe 20, the four-way valve 7 and the suction pipe 10. Then, it is repressurized by the compressor 4 and discharged as a high-temperature and high-pressure gas refrigerant to the main heat exchanger 15, and circulates through the above path.

Next, the four-way valve 7 is switched to a position where the inflow port 9 communicates with the second switching port 13 and the outflow port 11 communicates with the first switching port 12, respectively, and the first and second electromagnetic valves are connected. By operating the compressor 4 by closing the valves 17a and 17b respectively and opening the third, fourth and fifth electromagnetic valves 23a, 23b and 17c respectively, the second arrow indicated by the broken line arrow in the drawing is drawn. The refrigerant circulates along the circulation path, and the container 1 and the cylinder 2 are switched to a heating operation in which they are heated by the refrigerating device 3.

In this heating operation, the high-temperature and high-pressure gas refrigerant discharged from the compressor 4 is discharged from the discharge pipe 8 and the four-way valve 7.
-First gas branch pipe 20a and second via the second gas pipe 20
After branching into the gas branch pipe 20b, it flows into the container heat exchanger 5 and the cylinder heat exchanger 6. Then, after the container 1 and the cylinder 2 are heated by heat radiation to the surroundings, they are joined at the first bypass pipe 22 via the first bypass branch pipe 22a and the second bypass branch pipe 22b. After that, when passing through the first heat exchange pipe 21a of the auxiliary heat exchanger 21, it radiates heat to the refrigerant flowing in the second heat exchange pipe 21b described later to be condensed.

The condensed liquid refrigerant flows into the main heat exchanger 15 through the second bypass pipe 25 and the first gas pipe 14, and exchanges heat when passing through the heat exchange refrigerant pipe 15a of the main heat exchanger 15. After further radiating heat to the water pipe 15b to completely condense and remove water when passing through the dryer 41,
When it flows into the third liquid branch pipe 16c and passes through the constant pressure expansion valve 24 provided in the third liquid branch pipe 16c, it adiabatically expands to become a low-temperature low-pressure liquid refrigerant.

The liquid refrigerant after passing through the constant pressure expansion valve 24 has a predetermined pressure (for example, about 5 kg / min.) Regardless of the pressure when flowing into the constant pressure expansion valve 24. cm ² ). Therefore, by selecting, as the constant pressure expansion valve 24, a constant pressure expansion valve having a specification that allows the liquid refrigerant to flow out at a pressure suitable for the suction pressure in the compressor 4, so that the compressor is not affected by external factors such as ambient temperature. It is possible to return the refrigerant to 4 at an appropriate pressure.

The liquid refrigerant is then added to the auxiliary heat exchanger 21.
While flowing into the second heat exchange pipe 21b and flowing through the pipe 21b, it absorbs heat from the high-temperature refrigerant flowing through the first heat exchange pipe 21a and evaporates to become a gas refrigerant. afterwards,
This gas refrigerant is returned to the compressor 4 through the third bypass pipe 26, the accumulator 19, and the suction pipe 10, becomes a high temperature and high pressure gas refrigerant again, and circulates in the above path.

As described above, in the heating operation in the above configuration, after passing through the container heat exchanger 5 and the cylinder heat exchanger 6, the first heat exchange pipe 21a of the auxiliary heat exchanger 21 and the main heat exchanger 15 are provided. The refrigerant is condensed in the heat exchange refrigerant pipe 15a, and the constant pressure expansion valve 24 of the third liquid branch pipe 16c
In step 1, the pressure is reduced to a predetermined pressure (about 5 kg / cm ² ). As described above, the constant pressure expansion valve 24 reduces the pressure so that the outflow pressure becomes constant regardless of the inflow pressure.
For example, even when the discharge pressure from the compressor 4 rises with the rise in ambient temperature in the summer, the refrigerant pressure after passing through the constant pressure expansion valve 24 can be made constant and returned to the compressor 4. . As a result, the compressor 4 is operated in an operating state within the normal working pressure range, so that even if the ambient temperature rises, the compressor 4 is not overloaded and the suction pressure is stable. As a result, the discharge pressure also rises steadily, so that it is possible to stably supply the high temperature gas refrigerant to the container 1 and the cylinder 2.

Further, in comparison with the above-mentioned conventional structure,
In the above-mentioned conventional configuration, shortly after the start of the heating operation, as shown in the graphs a to c of FIG. 3, the discharge pressure dropped for a moment with the opening of the bypass pipe. In the above configuration, as is clear from the graph d indicated by the two-dot chain line in the figure, the discharge pressure of the compressor 4 continues to rise without dropping from the start of the heating operation, and
It is possible to stably reduce the time required for the discharge pressure to stabilize.

During the above heating operation, the first gas pipe 1
4 is connected to the suction side of the compressor 4, and as a result, the opening / closing valve 39 provided in the water pipe 38 is automatically controlled to open / close. Therefore, the unnecessary water circulation to the main heat exchanger 15 is stopped, so that the operating cost can be reduced.

Further, instead of using the above-mentioned constant pressure expansion valve 24 as the pressure adjusting means, for example, a bypass pipe connected from the first heat exchange pipe 21a of the auxiliary heat exchanger 21 to the second heat exchange pipe 21b is used. Further, the bypass pipe is branched into a plurality of pipes, and each of the branch pipes is provided with a capillary tube having a different pressure reducing ratio, and the pressure of the refrigerant flowing into the bypass pipe is detected. By providing a switch and a solenoid valve or the like for controlling the flow of the refrigerant so as to pass through a capillary tube having a large ratio, it is also possible to make the refrigerant pressure constant after passing through the bypass pipe, but in this configuration, While many parts such as a plurality of capillary tubes, the above-mentioned switches and solenoid valves are required, the constant pressure described in this embodiment is required. Configuration using the expansion valve 24, since fewer parts, along with the size of the apparatus can be achieved, there is an advantage that it is possible to suppress the rise in production costs of the device.

For example, when R-502 is used as the refrigerant, the conditions are set so that condensation occurs in the first heat exchange pipe 21a at a temperature of about 45 ° C. corresponding to a condensation pressure of about 18 kg / cm ^2. Then, from the compressor 4, 1
A high temperature gas refrigerant of about 00 to 120 ° C. can be discharged. As a result, it is possible to supply a sufficiently high temperature gas refrigerant to the container heat exchanger 5 and the cylinder heat exchanger 6 to heat the container 1 and the cylinder 2 to a temperature exceeding the sterilization temperature described above. . And the compressor 4
Is maintained in the operating condition within the normal working pressure range,
By rapidly raising the temperature of the container 1 and the cylinder 2 that have been cooled until then, the time required for the sterilization treatment can be shortened, and the container 1 and the cylinder 2 are stably supplied with the high-temperature gas refrigerant for heating over the required time. can do.

Moreover, in the above description, the condensation and evaporation in the auxiliary heat exchanger 21 are caused by the transfer of heat between the refrigerants flowing through the first heat exchange pipe 21a and the second heat exchange pipe 21b, respectively. Therefore, it is not necessary to provide, for example, a blower fan, water piping, water circulation equipment, etc. compared to the case where the air heat exchanger and the water heat exchanger are configured as separate condensers and evaporators. Therefore, the structure is simplified and can be downsized, and the operating cost can be reduced.
Further, since the influence on the heat exchange capacity by the air temperature or the water temperature changing with the air temperature is reduced, the heating operation can be made more stable. Furthermore, there is no noise associated with the driving of the fan in the case of the air heat exchanger, for example, so that the device has lower noise.

The present invention is not limited to the above embodiment. For example, in the above embodiment, an example in which the main heat exchanger 15 is a water heat exchanger has been described. It is also possible to configure the vessel with an air heat exchanger that exchanges heat with the air. In this case, by controlling the operation of the fan in the main heat exchanger by pressure or temperature according to the discharge pressure of the compressor 4, stable cycle operation can be maintained and power consumption of the fan can be reduced. be able to. Further, the gas refrigerant is used as the auxiliary heat exchanger 2 during the heating operation.
The configuration in which the first heat exchange pipe 21a and the heat exchange refrigerant pipe 15a of the main heat exchanger 15 condense and flow into the constant pressure expansion valve 24 has been described. Without passing through the first heat exchange pipe 21a
It may be configured such that it is condensed only by itself and then flows into the constant pressure expansion valve 24. Further, instead of the capillary tubes 18a and 18b described in the above embodiment, an expansion valve such as a manual expansion valve, a temperature expansion valve, a constant pressure expansion valve, or a float expansion valve can be used.

[0045]

As described above, the frozen dessert making machine of the present invention is
Container for storing frozen dessert raw material and cylinder for manufacturing frozen dessert, compressor for pressurizing and discharging heat medium, heat exchange for container for exchanging heat between the heat medium and each of the container and cylinder Heat exchanger for a heat exchanger and a cylinder, a medium heat exchanger having first and second heat exchange pipes arranged so that heat exchange occurs between the heat mediums flowing inside, and a heat medium compression And a pressure adjusting means for reducing the pressure to a predetermined pressure within the set suction pressure range of the machine to adiabatically expand the heat medium discharged from the compressor for heat exchange for the container and heat exchange for the cylinder. Forming a medium circulation path for returning from each of the reactors to the compressor by sequentially passing through the first heat exchange pipe of the medium heat exchanger, the pressure adjusting means, and the second heat exchange pipe of the medium heat exchanger. Connected to each other by piping It is formed.

Therefore, it is possible to suppress the influence of the fluctuation of the ambient temperature and the like, and to stably perform the operation of heating the container or the cylinder above the sterilization temperature without increasing the load of the compressor. In addition, since the number of parts can be reduced, the control during heating operation can be simplified and
This has the effect of making it possible to reduce the size of the device and suppress the rise in manufacturing costs.

[Brief description of drawings]

FIG. 1 is a heat medium circuit diagram in a frozen dessert making machine according to an embodiment of the present invention.

FIG. 2 is a heat medium circuit diagram in a conventional frozen dessert making machine.

FIG. 3 shows changes in discharge pressure of the compressor during heating operation in the conventional frozen dessert making machine and changes in discharge pressure of the compressor during heating operation in the frozen dessert making machine according to one embodiment of the present invention. It is a graph which contrasts and shows.

[Explanation of symbols]

 1 Container 2 Cylinder 4 Compressor 5 Container Heat Exchanger 6 Cylinder Heat Exchanger 21 Auxiliary Heat Exchanger (Medium Heat Exchanger) 21a First Heat Exchange Pipe 21b Second Heat Exchange Pipe 24 Constant Pressure Expansion Valve (Pressure) Adjustment means)

Claims (1)

[Claims] 1. A container for storing raw materials for frozen desserts, a cylinder for manufacturing frozen desserts, a compressor for pressurizing and discharging a heat medium, and heat exchange between the heat medium and each of the containers and cylinders. A heat exchanger for containers and a heat exchanger for cylinders, and a medium heat exchanger having first and second heat exchange pipes arranged so that heat exchange occurs between the heat mediums respectively flowing inside. And a pressure adjusting means for decompressing the heat medium to a predetermined pressure within the set suction pressure range of the compressor and adiabatically expanding the heat medium. And the medium to be returned to the compressor from each of the cylinder heat exchanger and the first heat exchange pipe of the medium heat exchanger, the pressure adjusting means, and the second heat exchange pipe of the medium heat exchanger in order. Connected to each other by piping that forms a circulation path Ice confection producing device which is characterized in that it is.