JPH0424379Y2 - - Google Patents

Description

[Detailed description of the invention] Industrial application field This invention relates to an automatic ice maker, and in particular to an automatic ice maker configured so that the amount of hot gas circulated during deicing operation can be adjusted according to the ambient temperature.

Prior Art In the schematic configuration of a conventional fountain-type automatic ice maker shown in FIG. 7, reference numeral 1 indicates a downwardly opening ice making chamber disposed in the ice making section. A large number of ice-making compartments 2 are defined by partition plates. An evaporator 3 connected to the illustrated refrigeration system is closely arranged in a meandering manner on the outer upper surface of the ice-making compartment 1, and a water tray 4 is tiltably disposed below the ice-making compartment 1. That is, one end of the water tray 4 is pivotally supported by the machine frame, and the other end is connected to the actuator motor AM shown in FIG. 8 via a lever, so that the water tray 4 is held in a horizontal position during the ice making cycle. The ice making chamber 1 is closed from below.
and the actuator motor during the de-icing cycle.
The AM rotates and tilts the water tray 4 downward to open the ice making chamber 1. Also, the valve of the refrigeration system is switched, hot gas is supplied to the evaporator 3 to warm the ice making compartment 1, and the ice cubes produced in the small ice making compartment 2 are released and stored in a water storage tank (not shown). It's becoming like that.

A water fountain hole 7 is bored in the water tray 4 at a position corresponding to each of the ice-making compartments 2, and this fountain hole 7 communicates with a distribution pipe 6 arranged on the back surface of the water tray. An ice-making water tank 5 is provided below the water tray 4.
The ice-making water sent from the pump motor PM to the pressure chamber via the water pipe 8 is fed under pressure to the distribution pipe 6, and is fed into the corresponding ice-making chamber 2 from a large number of water fountain holes 7, and then the ice-making water is fed into the corresponding ice-making chamber 2 from the evaporator 3. As a result, ice cubes are gradually formed in layers on the inner surface of the ice-making chamber 2 which has been cooled to below freezing point. The ice-making residual water that has not yet frozen is returned to the tank 5 and collected through return holes 9 formed in the water tray 4 corresponding to each ice-making chamber 2.
Note that the water tank 5 is supplied with a required amount of ice-making water necessary for the ice-making cycle from an external water supply system 10 via a water supply valve WV.

The outlet side of the evaporator 3 is connected to the suction port of a compressor 20 via a suction pipe 17, and the discharge pipe 14 connected to the discharge port of the compressor 20 is connected to a condenser 11 equipped with a fan motor FM. ing. This condenser 11 is connected to a dryer 12 via a liquid pipe 15.
The outlet side of the dryer 12 is connected to a liquid pipe 16 and an expansion valve 1.
3 to the inlet side of the evaporator 3. The discharge pipe 14 is branched on the side near the inlet of the condenser 11 and connected to a hot gas pipe 18 having a hot gas valve HV, and the inlet side of the condenser 3 is connected to the hot gas pipe 18 by bypass. Further, an ice-making detection thermometer Th ₁ is disposed at an appropriate upper surface position of the ice-making chamber 1, and a de-icing detection thermometer Th ₂ is disposed at a side position of the ice-making chamber 1.

FIG. 8 shows a connection diagram of the electrical system in the automatic ice making machine described above. This changeover switch in Figure 8
SW is the actuator motor during the de-icing cycle.
It is provided to switch from the ice making side contact a to the deicing side contact b when the water tray 4 is tilted by a predetermined angle due to the rotation of the AM. In addition, S ₁ indicates a reset switch, ice making detection thermo Th ₁ detects the completion of ice making and switches its contact a to contact b, and deicing detection thermo Th ₂ detects the completion of ice making and closes the contact. It is starting to become a reality.

There is an ice-making detection thermometer at contact a of the changeover switch SW.
Th ₁ and reset switch S ₁ are connected in parallel, and a cooling fan motor FM and a pump motor PM are connected in parallel to contact a of ice-making detection thermo Th ₁ .
Furthermore, the contact b of the ice-making detection thermometer _Th1 is connected to the reset switch _S1 and the actuator motor AM. Contact b of the changeover switch SW has a de-icing detection thermometer connected to the actuator motor AM.
Th ₂ , hot gas valve HV, and water supply valve WV are connected in parallel.

The operation of the conventional fountain-type automatic ice maker having this configuration will be described next. The changeover switch SW provided on the water tray 4 is connected to the contact a side during the ice making cycle, and the ice making detection thermometer _Th1 is connected to the contact a side, and is connected to the compressor 20, the cooling fan motor FM, and the pump motor PM. Power is on. The refrigerant compressed by the compressor 20 is discharged and supplied to the condenser 11 through the discharge pipe 14, cooled by a cooling fan to become a high-pressure liquid, passed through the dryer 12 to remove moisture, and after being depressurized by the expansion valve 13. , and is fed to the evaporator 3 where it evaporates to cool the ice making compartment 1. The refrigerant gas vaporized in the evaporator 3 returns to the compressor 20 again through the suction pipe 17 and repeats the previous cooling cycle.

When ice cubes are generated in the ice making compartment 2 and ice making is completed, the ice making detection thermo _Th1 detects this and switches its contact to the "b" side to enter the deicing cycle.
This allows the fan motor FM and pump motor PM to
While the current is cut off, the actuator motor AM is energized and the water tray 4 is tilted. And a changeover switch SW arranged on the support frame of the water tray 4
contacts the arm of the motor AM and switches to the contact b side, and the hot gas valve HV and water supply valve WV are energized and opened. As a result, the refrigerant compressed by the compressor 20 is directly introduced into the evaporator 3 via the pipe 18 as a high-temperature hot gas before being cooled by the condenser 11, heating the ice-making compartment 1 and increasing its temperature. Promote de-icing.

Problems to be Solved by the Invention In the conventional automatic ice maker mentioned above, the time required for the ice cubes to leave the ice maker 1 after entering the deicing cycle (deicing time) generally depends on the outside temperature, etc. of the ice maker. depends on the ambient temperature, e.g. becomes shorter in summer,
It has been confirmed that it takes longer in winter. In other words, the refrigerant pressure in the pipes of the refrigeration system increases when the ambient temperature is high, such as in the summer, and the amount of hot gas circulated increases, and conversely, when the ambient temperature is low, such as in the winter, the amount of hot gas circulated decreases. . Therefore, if the pressure on the low pressure side (suction side) of the compressor 20 is set according to the temperature conditions in the summer, the pressure on the low pressure side of the compressor will further decrease in the winter, and the amount of hot gas circulating through the evaporator 3 will decrease. becomes less. For this reason, there are problems in that the heating time of the ice making chamber 1 becomes longer, the time for deicing becomes longer, the ice making capacity is significantly reduced, and the power consumption increases.

Further, the amount of refrigerant circulated is greater during the deicing cycle than during the ice making cycle because the refrigerant does not go through the pressure reducing means 13, and the load on the compressor 20 increases during the deicing cycle. Even during the same deicing cycle, during high temperatures such as summer when the amount of hot gas circulating increases,
The load on the compressor 20 further increases. Therefore, if the low pressure side pressure of the compressor 20 is set according to the winter season,
In the summer, there is a problem in that the compressor becomes overloaded during the deicing cycle, leading to failures such as motor burnout. Moreover, if the ice maker is actually used for a long time, dust and the like will adhere to the surface of the condenser 11, impeding heat transfer and reducing heat exchange efficiency. This further causes an increase in the amount of refrigerant circulation, which promotes overloading of the compressor 20. Therefore, the amount of refrigerant circulation cannot be set in advance to be unnecessarily large.

However, when the amount of refrigerant circulation is reduced, the following problems are pointed out. In other words, the hot gas having a small amount of circulation cannot uniformly heat the tube from the inlet side to the outlet side of the evaporator 3 because its heat capacity is small. For this reason, even if the inlet side can be heated to a high temperature, the closer you get to the outlet side, the higher the temperature cannot be ensured, making it difficult to remove the ice cubes from each ice making compartment 2 all at once, and deicing time becomes longer. become longer.

Therefore, in order to remove all the ice at once without any time delay, a gap is generally formed in advance between the lower end of the ice-making compartment 1 and the surface of the water tray 4, and each ice cube is connected to this gap. It is designed so that rib-shaped ice is generated. Therefore, if the deicing time is long, the amount of ice cubes melted in the ice making chamber 2 near the inlet of the evaporator 3 will be larger than the amount of ice cubes melting in the ice making chamber 2 near the outlet of the evaporator 3. When all the ice cubes are separated by their own weight, a large amount of ice cubes with non-uniform shapes are produced.

The above-mentioned problems with automatic ice makers are not limited to fountain type ice makers, but can also occur with other types of ice makers, such as falling type ice makers. These problems can be solved by adjusting the amount of hot gas circulation depending on the ambient temperature because the system uses only one hot gas valve, which is opened during the deicing cycle regardless of the ambient temperature, as shown in Figure 9. This is due to the inability to do so.

Purpose of the Invention The object of the present invention is to provide an automatic ice maker that can adjust the hot gas circulation amount depending on the ambient temperature, in order to solve the above-mentioned problems inherent in the conventional automatic ice maker. shall be.

Means for Solving the Problems In order to suitably solve the above problems, the present invention has the following features:
It consists of an evaporator disposed in the ice making section, a condenser that supplies liquefied refrigerant to the evaporator via a pressure reducing means, and a compressor that compresses the vaporized refrigerant from the evaporator and sends it to the condenser. In an automatic ice maker equipped with a refrigeration circuit, the first piping directly bypasses the compressed vaporized refrigerant before flowing into the condenser to the inlet side of the evaporator, and the first hot gas valve opens and closes the first piping. a second piping that directly bypasses the refrigerant flowing out of the condenser to the inlet side of the evaporator; a second hot gas valve that opens and closes the second piping; A timer for opening a valve to introduce the liquefied refrigerant in the condenser into the hot gas circulation system is provided, and the predetermined time set in the timer is variable.

Function The automatic ice maker of the present invention having the above-mentioned configuration has the following features:
During deicing operation, the liquefied refrigerant in the condenser is introduced into the hot gas circulation path, increasing the amount of hot gas circulation. Since this amount of increase depends on the predetermined time of the timer, when the outside temperature is high and the refrigerant pressure in the refrigeration circuit is high, the predetermined time is set to zero, and when the outside temperature is low, the predetermined time is set appropriately.

Embodiments Next, preferred embodiments of the automatic ice maker according to the present invention will be described with reference to FIGS. 1 to 6. FIG. 1 is a schematic diagram of the ice making section of a fountain-type automatic ice maker according to an embodiment of the present invention, and FIG. 2 is a refrigeration circuit diagram thereof. In addition, in Figure 1, the seventh
Components that are the same as those explained in the figures are given the same reference numerals and their explanations will be omitted.

In the refrigeration circuit of this embodiment, the conventional hot gas piping and hot gas valve are shown as first piping 18 and first hot gas valve _HV1 , respectively. In addition to this configuration, this embodiment newly includes:
A second pipe 19 that directly bypasses the liquefied refrigerant flowing out of the condenser 11 to the inlet side of the evaporator 3, and a second hot gas valve _HV2 that opens and closes the second pipe 19 are provided.

In the embodiment shown in FIGS. 1 and 2, the sides where the first pipe 18 and the second pipe 19 connect to the evaporator 3 are combined into one pipe, but the sides of the evaporator 3 are connected separately. It may be configured to be connected to the entrance side. Further, as shown in FIGS. 3 and 4, a liquid receiver 30
In the case of a refrigeration circuit having
9 may be led out from either the front or rear side of the liquid receiver 30.

FIG. 5 shows a connection diagram of the electrical system of the automatic ice maker according to this embodiment. According to the electrical connection of this embodiment, in addition to the conventional connection configuration shown in FIG.
HV ₂ is arranged in parallel with the first hot gas valve HV ₁ ,
Furthermore, a timer T is provided which counts a set time from the start of energization and opens the on/off switch when the count is up.

The operation of the automatic ice maker according to this configuration will be explained next. Note that the operation during the ice making operation is the same as the operation in the conventional example described with reference to FIGS. 7 and 8, so only the example of the operation during the deicing operation will be described. When ice making is completed, the ice making completion detection thermo _Th1 detects this and switches the contact from the "a" side to the "b" side, driving the actuator motor AM to tilt the water tray 4. As a result, the changeover switch SW switches to contact b, and the first
Hot gas valve HV ₁ and second hot gas valve HV ₂
is energized, both valves HV ₁ and HV ₂ open, and timer T starts counting the set time.
As a result, the high temperature hot gas discharged from the compressor 20 is branched and supplied to the first piping 18 and the condenser 11 in FIG.
The hot gas branched into the first pipe 18 via the HV ₁ flows into the evaporator 3. On the other hand, the liquefied refrigerant stored in the condenser 11 (conventionally, this liquefied refrigerant remained in the condenser during deicing operation and was not circulated in the refrigeration circuit) is transferred from the liquid pipe 15 to the second hot gas. flows into the second pipe 19 via the valve HV ₂ ,
It flows into the evaporator 3. This makes it possible to remove ice in a short time.

When timer T counts up the set time,
The second hot gas valve HV ₂ is closed. If this set time is long, all of the liquefied refrigerant stored in the condenser 11 becomes gas-phase refrigerant while repeating circulation, and if it is short, the liquefied refrigerant corresponding to the length of the set time is transferred to the condenser 11. It will flow from within.
After the set time has expired, the hot gas is circulated only through the first pipe 18, but since the liquefied refrigerant that has flowed out from the condenser 11 during the set time is circulated as hot gas, the amount of hot gas circulation is reduced accordingly. increases. Therefore, when the outside temperature is low, the set time of the timer T is lengthened to increase the hot gas circulation amount and shorten the time until deicing. Furthermore, when the outside temperature is high, the set time of the timer T is set to zero to prevent the second hot gas valve _HV2 from opening, thereby avoiding overload of the compressor 20 due to an increase in the amount of hot gas circulation.

When this deicing is completed and the cooling load on the ice making compartment 2 is removed, the temperature of the ice making compartment 1 rises rapidly due to hot gas circulation, and the deicing detection thermo _Th2 detects this and closes its contact. As a result, the actuator motor AM is reversely energized, the water tray 4 is returned to the original horizontal position, the ice making chamber 1 is closed, and the changeover switch SW is switched to contact a to proceed to the next ice making operation.

FIG. 6 shows a connection diagram of an electrical system of an automatic ice maker according to a second embodiment of the present invention. In this embodiment, _a switch SW1 that switches and connects the first hot gas valve _HV1 and the second hot gas valve _HV2 , which are arranged in parallel, to the power bus line is configured to be controllable by a timer T. Then, until the timer T times out the time limit, switch _SW1 is connected to contact a.
Connect to the side and open the second hot gas valve HV ₂ ,
When the timer T times out, the switch is set to the contact b side to open the first hot gas valve _HV1 . and a changeover switch
When the SW is switched to contact b and deicing operation is started, the timer T starts counting the time limit, and the second hot gas valve HV ₂ opens to drain the liquefied refrigerant in the condenser 11. Some of it circulates and becomes hot gas. Also, when timer T times out,
The second hot gas valve HV ₂ is closed and the first hot gas valve HV ₁ is opened, so that the hot gas is circulated through the first hot gas valve HV ₁ .

In the first and second embodiments described above, the amount of the liquefied refrigerant stored in the condenser 11 that is vaporized and circulated as hot gas is controlled by adjusting the set time of the timer T. I can,
Moreover, since an outside temperature detection thermometer is not required, the ice making machine has the advantage of being able to be manufactured at a low cost. Note that the timer T
The set time may be automatically corrected according to changes in outside temperature.

In each of the above embodiments, a configuration in which the present invention is applied to a fountain-type automatic ice maker equipped with an ice maker that opens downward has been described. Whether it is a plate method that freezes sheet ice, an open cell method that has an independent ice-making chamber that opens downward, or a block method that freezes water in a water tank, hot gas is pumped into the evaporator during deicing. As long as it circulates to melt the ice formed between the ice making section and the ice produced, it can be suitably used in all ice making methods. Further, the condenser is not limited to an air-cooled type, but may be a water-cooled type.

Effects of the invention According to the invention, the amount of hot gas circulation can be controlled based on the ambient temperature of the ice maker, resulting in the following effects.

(1) Since the deicing time can be set short even at low temperatures, ice making capacity is improved.

(2) Reduces power consumption and saves energy.

(3) Compressor overload at high temperatures is prevented.

(4) Even at low temperatures, the amount of hot gas circulated is large and the heat capacity is large, so the heating of the ice making chamber during the deicing cycle is uniform, and therefore ice of good quality and stable shape can be obtained.

(5) Since the structure is simple, it can be manufactured at low cost and maintenance is easy.

[Brief explanation of the drawing]

The drawings show an embodiment of the automatic ice maker according to the present invention, in which FIG. The refrigeration circuit diagram of the automatic ice maker shown in the figure, FIGS. 3 and 4 are refrigeration circuit diagrams according to different embodiments, respectively.
Fig. 5 is a connection diagram of the electrical system of the first embodiment, Fig. 6 is a connection diagram of the electrical system of the second embodiment, Fig. 7 is a schematic configuration diagram of a conventional fountain ice maker, and Fig. 8 is a conventional FIG. 9 is a diagram illustrating the operation of a conventional hot gas valve. 1... Ice making room, 3... Evaporator, 11... Condenser, 13... Expansion valve, 18... First piping, 19...
...Second piping, 20...Compressor, HV ₁ ...First hot gas valve, HV ₂ ...Second hot gas valve, T...
...Timer.

Claims (1)

[Claims for Utility Model Registration] [1] An evaporator 3 disposed in the ice making section 1, a condenser 11 that supplies liquefied refrigerant to the evaporator 3 via a pressure reducing means 13, and a a compressor 2 that compresses vaporized refrigerant and sends it to the condenser 11;
0, a first pipe 18 that directly bypasses the compressed vaporized refrigerant before flowing into the condenser 11 to the inlet side of the evaporator 3; a first hot gas valve HV ₁ that opens and closes 18; a second pipe 19 that bypasses the refrigerant flowing out from the condenser 11 directly to the inlet side of the evaporator 3; and a second hot gas valve that opens and closes the second pipe 19. HV ₂ , and a timer T that opens the second hot gas valve HV ₂ for a predetermined time from the start of deicing operation to introduce the liquefied refrigerant in the condenser 11 into the hot gas circulation system, and the timer T An automatic ice maker characterized in that the predetermined time set for the ice maker is variable. [2] The automatic ice maker according to claim 1, wherein the set time of the timer T can be automatically corrected according to changes in outside temperature.