JP2005090947A - Auger ice maker - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an auger ice maker which maintains a stable freezing cycle without a compressor being superheated, while controlling ice making capability so that no excessive load occurs in a geared motor. <P>SOLUTION: In a freezing circuit of the auger ice maker, a bypass passage 8 connected to an inlet side 7 of an expansion valve 5 is provided on an outlet side 6 of the compressor 3. This bypass passage 8 is provided with an solenoid valve 9 which opens the bypass passage 8 for temporarily reducing ice making capability by inputting a hot gas to the expansion valve 5. The numbers of the bypass passage and solenoid valve provided, respectively, may be two or more. The ice maker may be separately provided with a refrigerant amount adjusting circuit which adjusts the amount of a refrigerant supplied which is condensed by a condenser 4 and supplied to the expansion valve 5. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an auger type ice making machine.

In an auger type ice making machine, when the ambient temperature or ice making water temperature decreases and the ice making capacity increases, ice clogging at the fixed blade portion and freezing of the ice making cylinder are likely to occur, and an excessive load is generated on the geared motor. When the geared motor is in such a state, there is a possibility that the motor or the gear is damaged due to a motor lock. For this reason, Patent Document 1 proposes a method of temporarily reducing the ice making capacity of an auger type ice making machine to avoid overloading of the geared motor.
In FIG. 1 of Patent Document 1, an overcurrent value corresponding to an overload of a geared motor is detected, and in an overload state, an auger type in which hot gas in a discharge pipe of the compressor is injected into a suction pipe of the compressor. An ice making machine is disclosed. A method of injecting hot gas into the inlet of an evaporator is known.

JP 2003-42610 A

However, if hot gas is injected into the suction pipe of the compressor, the compressor is overheated, causing a compressor failure, and energy efficiency is also reduced.
On the other hand, when hot gas is injected into the inlet of the evaporator, the temperature in the evaporator rises rapidly, the expansion valve becomes uncontrollable, and the refrigeration cycle operation of the auger type ice making machine becomes unstable.
The present invention has been made to solve such problems, and has an ice-making ability so as not to generate an excessive load on the geared motor while maintaining a stable refrigeration cycle without overheating the compressor. An object is to provide an auger type ice making machine that can be controlled.

An auger type ice making machine according to the present invention is an auger type ice making machine having a refrigeration circuit for circulating a refrigerant in the order of a compressor, a condenser, an expansion valve and an evaporator, the upstream end of which is connected to the outlet side of the compressor. A bypass passage whose downstream end is connected to the inlet side of the expansion valve, and an opening / closing means for opening and closing the bypass passage. By opening the opening / closing means, the high-temperature and high-pressure refrigerant gas on the outlet side of the compressor It is sent to the inlet side of an expansion valve via.
A plurality of bypass passages and opening / closing means may be provided.
Furthermore, you may provide the refrigerant | coolant amount adjustment circuit which adjusts the supply amount of the refrigerant | coolant condensed with a condenser and supplied to an expansion valve.

  According to this invention, the ice making capacity of the auger type ice making machine can be controlled so that an excessive load is not generated on the geared motor while maintaining a stable refrigeration cycle without overheating the compressor.

Embodiments of the present invention will be described below with reference to the accompanying drawings.
Embodiment 1 FIG.
FIG. 1 shows a configuration of an auger type ice making machine according to an embodiment of the present invention.
The auger type ice making machine has a refrigeration casing 1 which is a vertically long ice maker, and a cooling pipe 2 constituting an evaporator of a refrigeration circuit is wound around the outer peripheral surface thereof.
The cooling pipe 2 is connected with a compressor 3, a condenser 4 and an expansion valve 5 in series by pipes A, B, C, and D, which are connected to a refrigeration circuit that circulates a refrigerant in the direction of the arrow shown in the figure. Constitute. Further, a bypass passage 8 connected to the inlet side 7 of the expansion valve 5 is provided on the outlet side 6 of the compressor 3. The bypass passage 8 is provided with an electromagnetic valve 9 that opens and closes the bypass passage 8.
An auger 11 that is rotationally driven by a geared motor 10 is provided inside the refrigeration casing 1. The discharge cylinder 12 connected at the top of the refrigeration casing 1 is provided with a fixed blade portion (not shown) that compresses and shapes the ice scraped off by the auger 11.

  Furthermore, this auger type ice making machine is provided with a control device 13 for controlling the opening and closing of the electromagnetic valve 9. The control device 13 is provided with a current sensor 14 as overload detection means for detecting an overload state of the geared motor 10. The current sensor 14 detects a current flowing through the geared motor 10, and the control device 13 determines whether or not the geared motor 10 is in an overload state based on this current value. For example, the control device 13 determines that the geared motor 10 is in an overload state when the current value of the current sensor 14 is equal to or greater than a predetermined current value for a predetermined time.

Next, the operation of the auger type ice making machine according to the embodiment of the invention will be described.
First, the case where the ice making capacity is in a normal state will be described.
The refrigerant flowing through the refrigeration circuit is compressed by the compressor 3 to become hot gas, which is a high-temperature and high-pressure gas refrigerant, and is cooled and condensed by the condenser 4. The high-pressure liquid refrigerant that has become slightly cooler by the condenser 4 is expanded by the expansion valve 5 and is evaporated by the cooling pipe 2 to take the heat of the refrigeration casing 1. Thereby, ice making is performed in the freezing casing 1.
The auger 11 driven by the geared motor 10 scrapes off the ice formed on the inner peripheral surface of the refrigeration casing 1, and the scraped ice is compressed and molded by the fixed blade portion and sent to the discharge cylinder 12.

On the other hand, when the ambient temperature of the auger type ice making machine or the temperature of the ice making water is lowered, the ice making capacity is increased more than necessary. In this case, since the load of the geared motor 10 increases and the current value increases, the control device 13 determines that the geared motor 10 is in an overload state based on the current value of the current sensor 14, and the electromagnetic valve 9 open.
When the electromagnetic valve 9 is opened, hot gas is introduced into the inlet side 7 of the expansion valve 5, mixed with the liquid refrigerant cooled by the condenser 4, and the refrigerant in a flash gas state is sent to the expansion valve 5. Become. When hot gas is mixed with the liquid refrigerant, the amount of liquid refrigerant passing through the expansion valve 5 is reduced, so that the amount of refrigerant evaporated in the cooling pipe 2 is reduced and the amount of ice making is reduced. As described above, since the ice making capacity is reduced when an overload of the auger type ice making machine is detected, an excessive load is not applied to the geared motor 10. Accordingly, it is possible to prevent ice clogging, freezing of the refrigeration casing 1, damage to the auger 11, wear of a bearing supporting the auger 11, and damage to the geared motor 10.
Further, since the amount of the superheated refrigerant supplied from the cooling pipe 2 to the compressor 3 is suppressed to a small amount, the compressor 3 is prevented from being overheated. Therefore, the internal parts of the compressor 3 are not abnormally worn, and damage to the compressor 3 and reduction in energy efficiency due to overheating operation can be prevented.

The control device 13 determines that the geared motor 10 is in an overload state when the current value of the current sensor 14 is equal to or greater than the predetermined current value for a predetermined time, but is not limited thereto. Focusing on the appearance of a hunting phenomenon in which the current value increases or decreases due to fluctuations in the load on the geared motor 10 at the start of freezing of the refrigeration casing 1, the geared motor 10 exceeds the hunting current value. You may determine with being in a load state.
The ambient temperature and ice making water temperature of the auger type ice making machine are detected using a temperature sensor, and when these temperatures are lower than a predetermined value, the control device 13 determines that the auger type ice making machine is in an overload state. You may do it.
Moreover, the pressure and temperature of the refrigerant | coolant in the cooling pipe 2 may be detected, and the control apparatus 13 may determine with the auger type ice making machine being an overload state based on these.
Further, the ambient temperature and ice making water temperature of the auger type ice making machine are detected using temperature sensors, and when these temperatures are lower than a predetermined value, the control device 13 determines that the auger type ice making machine is in an overload state. You may make it determine.
In the above-described embodiment, the refrigeration circuit applied to the auger type ice making machine has been described. However, as long as the refrigeration circuit has such a configuration, the device to be applied is not limited to the auger ice making machine.
In the following embodiments, the same reference numerals as those in FIG. 1 are the same or similar components, and thus detailed description thereof is omitted.

Embodiment 2. FIG.
FIG. 2 shows the configuration of an auger type ice making machine according to Embodiment 2 of the present invention. In the first embodiment, the bypass passage 8 connecting the outlet side 6 of the compressor 3 and the inlet side 7 of the expansion valve 5 is provided with the electromagnetic valve 9 for switching between two operations of opening and closing the passage. Instead of this, as shown in FIG. 2, a second expansion valve 21 may be provided.
The second expansion valve 21 is controlled by the control device 22 so that the valve opening is variable, and functions as an adjustment valve that adjusts the amount of hot gas that flows to the expansion valve 5 via the bypass passage 8. The control device 22 detects the ambient temperature of the auger type ice making machine, the ice making water temperature, the high pressure side pressure of the refrigeration circuit, the low pressure side pressure, the condensation temperature, the evaporation temperature, and the geared, which are detected using the sensor 24 that detects temperature and pressure. The opening degree of the second expansion valve 21 is determined based on the temperature of the machine room in which the motor 10 is accommodated.
Thereby, the mixing ratio of the hot gas to the liquid refrigerant can be changed, and the ice making capacity can be controlled to be constant even if the ambient temperature of the auger type ice making machine changes.

Embodiment 3 FIG.
FIG. 3 shows the configuration of an auger type ice making machine according to Embodiment 3 of the present invention. This auger type ice making machine is the same as the auger type ice making machine of the first embodiment shown in FIG. 1 except for the configuration of the piping between the condenser 4 and the connection point 31 of the bypass passage 8 on the inlet side 7 of the expansion valve 5. Is a change.
On the outlet side of the condenser 4, a main pipe 32 and a sub pipe 33 are provided in parallel, through which a high-pressure liquid refrigerant that has been condensed at the condenser 4 and slightly cooled down flows. The sub-pipe 33 has a narrow pipe diameter as compared with the main pipe 32 and has a large flow resistance so that the flow rate flowing per unit time becomes small. The main pipe 32 is provided with an electromagnetic valve 34 that opens and closes the main pipe 32 and is electrically connected to the control device 35.
The main pipe 32, the sub pipe 33, and the electromagnetic valve 34 constitute a refrigerant amount adjusting circuit that adjusts the supply amount of the refrigerant that is condensed by the condenser 4 and supplied to the expansion valve 5.

Next, the operation of the auger type ice making machine according to this embodiment will be described.
When the ice making capacity is in the normal state, the control device 35 opens the electromagnetic valve 34 and closes the electromagnetic valve 9. For this reason, as in the first embodiment, the refrigerant flowing through the refrigeration circuit is compressed by the compressor 3 to become hot gas, cooled by the condenser 4 and condensed to become liquid refrigerant. Thereafter, the liquid refrigerant is sent to the expansion valve 5 through both the main pipe 32 and the sub pipe 33. After that, as in the first embodiment, the refrigerant is expanded by the expansion valve 5 and evaporated by the cooling pipe 2, and the ice of the refrigeration casing 1 is taken away by taking heat from the refrigeration casing 1.

On the other hand, when the outside air temperature around the auger type ice maker decreases, the control device 35 closes the electromagnetic valve 34 when determining that the auger type ice maker is overloaded as in the first embodiment. Open the solenoid valve 9.
When the electromagnetic valve 34 is closed, the liquid refrigerant condensed by the condenser 4 passes only through the sub-pipe 33 having a large flow path resistance, so that the liquid refrigerant hardly flows through the expansion valve 5. Accordingly, the amount of liquid refrigerant flowing through the expansion valve 5 per unit time itself is reduced.
In addition, since the electromagnetic valve 9 of the bypass passage 8 is opened, hot gas is supplied to the inlet side 7 of the expansion valve 5, and at the connection point 31, the ratio of hot gas to the liquid refrigerant flowing from the condenser 4 is The amount of refrigerant passing through the expansion valve 5 further decreases.
Thus, when introducing the hot gas into the inlet side 7 of the expansion valve 5, the liquid refrigerant is allowed to pass only through the sub-pipe 33, and the amount of liquid refrigerant supplied from the condenser 4 to the expansion valve 5 is reduced. Compared to the first embodiment, the ice making ability can be reduced more effectively.

Embodiment 4 FIG.
FIG. 4 shows the configuration of an auger type ice making machine according to Embodiment 4 of the present invention. This auger type ice making machine is the auger type ice making machine of the first embodiment shown in FIG. 1 and is provided with two bypass passages for sending hot gas discharged from the compressor 3 to the inlet side 7 of the expansion valve 5. is there.
A first bypass passage 41 and a second bypass passage 43 connected to the inlet side 7 of the expansion valve 5 are provided on the outlet side 6 of the compressor 3. The bypass passages 41 and 43 are provided with electromagnetic valves 42 and 44, respectively. Each solenoid valve 42 and 44 is electrically connected to the control device 45.
Here, the first bypass passage 41 and the second bypass passage 43 are two-system hot gas bypass circuits provided to adjust the amount of hot gas sent to the expansion valve 5 without going through the condenser 4 in two stages. Configure. The first bypass passage 41 is used for adjusting the ice making capacity to limit the ice making capacity of the auger type ice making machine so as not to exceed a predetermined level, and the second bypass passage 43 further restricts the ice making capacity of the auger type ice making machine. It is used for overload prevention.

The operation of the auger type ice making machine according to this embodiment will be described.
When the outside air temperature around the auger type ice maker decreases and the ice making capacity increases, the control device 45 opens the electromagnetic valve 42 and the first bypass passage 41 is hot so that the ice making capacity of the auger type ice maker does not exceed a predetermined level. Adjust the gas volume.
When the ice making capacity further increases, the control device 45 opens both the electromagnetic valves 42 and 44 and supplies hot gas from both the first bypass passage 41 and the second bypass passage 43 to the inlet side 7 of the expansion valve 5. Prevents an auger ice machine from becoming overloaded.
As described above, the opening and closing of the first bypass passage 41 and the second bypass passage 43 are adjusted so that the ratio of the hot gas to the liquid refrigerant flowing from the condenser 4 is increased in two stages.

Next, the state of the refrigerant flowing through the refrigeration circuit of this auger type ice making machine will be described using the Mollier diagram of FIG.
First, the refrigerant of the auger type ice making machine in a certain state changes from a1 → b1 → c1 → d1 → a1 in FIG. 5, and the refrigeration effect is r1. From this state, when the outside air temperature decreases, the pressure of the high-pressure side refrigerant decreases. At this time, the refrigerant changes from a2.fwdarw.b2.fwdarw.c2.fwdarw.d2.fwdarw.a2. The refrigeration effect is increased from r1 to r2, and the ice making capacity is increased. In such a state, since the load applied to the geared motor 10 increases, the control device 45 opens the electromagnetic valve 42 and closes the electromagnetic valve 44. The hot gas supplied to the expansion valve 5 via the first bypass passage 41 is mixed with the supercooled liquid refrigerant from the condenser 4 to increase the dryness of the liquid refrigerant. The refrigerant moves from c2 to c21, and the refrigerant changes from a2 → b2 → c21 → d21 → a2. As a result, the ice making capacity is controlled so that the refrigeration effect is reduced from r2 to r3 substantially equal to r1.
Even in this state, when the ice making capacity is too high and the auger type ice making machine is overloaded, the control device 45 opens both the electromagnetic valve 42 and the electromagnetic valve 44, and the first bypass passage 41 and the second bypass passage 43. Hot gas is supplied to the expansion valve 5 via As a result, the point on the high pressure side of the liquid refrigerant moves from c21 to c22, and the refrigerant changes from a2 → b2 → c22 → d22 → a2. As a result, the ice making capacity is controlled so that the refrigeration effect is further reduced from r3 to r4, and overload of the auger type ice making machine is prevented.

It is the schematic which shows the structure of the freezing circuit of the auger type ice making machine which concerns on Embodiment 1 of this invention. It is the schematic which shows the structure of the freezing circuit of the auger type ice making machine which concerns on Embodiment 2 of this invention. It is the schematic which shows the structure of the freezing circuit of the auger type ice making machine which concerns on Embodiment 3 of this invention. It is the schematic which shows the structure of the freezing circuit of the auger type ice making machine which concerns on Embodiment 4 of this invention. It is the Mollier diagram explaining the condition of the refrigerant | coolant of the refrigerating circuit of the auger type ice making machine which concerns on Embodiment 4 of this invention.

Explanation of symbols

  1 Refrigeration casing, 2 Cooling pipe (evaporator), 3 Compressor, 4 Condenser, 5 Expansion valve, 8, 41, 43 Bypass passage, 9, 42, 44 Solenoid valve (opening / closing means), 32 Main piping (refrigerant amount) Adjustment circuit), 33 sub piping (refrigerant amount adjustment circuit), 34 solenoid valve (refrigerant amount adjustment circuit).

Claims (3)

In an auger type ice making machine equipped with a refrigeration circuit for circulating a refrigerant in the order of a compressor, a condenser, an expansion valve and an evaporator,
A bypass passage having an upstream end connected to an outlet side of the compressor and a downstream end connected to an inlet side of the expansion valve;
Opening and closing means for opening and closing the bypass passage,
An auger type ice making machine characterized in that the high-temperature and high-pressure refrigerant gas on the outlet side of the compressor is sent to the inlet side of the expansion valve through the bypass passage by opening the opening / closing means.   The auger type ice making machine according to claim 1, comprising a plurality of said bypass passages and said opening / closing means.   The auger type ice making machine according to claim 1, further comprising a refrigerant amount adjusting circuit that adjusts a supply amount of the refrigerant that is condensed by the condenser and supplied to the expansion valve.

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