JP2004347266A - Protection device of auger type ice making machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a protection device of an auger type ice making machine capable of coping with an abnormality with a simple structure. <P>SOLUTION: The protection device 30 comprises a delay timer which starts to count simultaneously with the start of an auger motor AM. A compressor CM is started by the count up of the delay timer to start ice making operation. Current carrying to a shock relay is started simultaneously, and a current-voltage converter contained therein detects a current change from the auger motor AM, and converts it to a voltage change followed by outputting. If no overload is applied to the auger motor AM, and the output voltage from the current-voltage converter does not reach an overload output voltage according to the overload current of the motor AM, a steady operation is continued as it is. When the output voltage from the current-voltage converter corresponds to the overload output voltage, the operation of the auger motor AM and the compressor CM is stopped. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a protection device for an auger type ice machine, and more particularly, to a protection device for an auger type ice machine that transfers ice frozen on an inner wall surface of a freezing casing while shaving off the ice by an auger screw driven by an auger motor. It is about.
[0002]
[Prior art]
Conventionally, in a kitchen such as a coffee shop or a restaurant, an ice maker for producing ice blocks of a required shape has been suitably used according to its use and purpose, and among them, small pieces such as chip ice and flake ice are included. There is an auger-type ice machine that continuously produces ice blocks. In this auger type ice making machine, when an ice making operation is started in a state where ice making water is stored at a predetermined level inside a cylindrical refrigeration casing, the casing is forcibly cooled by a refrigerant circulating through an evaporating pipe connected to the refrigeration system. As a result, ice-making water gradually starts to freeze from the inner wall surface of the casing, and layered thin ice is formed. An auger screw is inserted in the inside of the freezing casing, and by rotating the auger screw by the auger motor, the thin ice frozen on the inner wall surface of the freezing casing is transferred upward while being scraped off by the auger screw. Then, the flake ice transferred by the auger screw is compressed in the process of passing through the pressing head disposed inside the upper portion of the freezing casing to remove water, thereby producing compressed ice. Compressed ice is released and stored in a stocker.
[0003]
In the auger-type ice making machine, flake ice transferred by the auger screw may not easily pass through the pressing head due to various causes during the ice making operation. If the ice making operation is continued in this state, all the ice making water inside the freezing casing is frozen, or an excessive load is applied because the auger motor attempts to continue rotation, and eventually the auger motor itself is burned, damaged or damaged. The ice making mechanism may be damaged.
[0004]
In view of the above, there is a device that copes with the above-described abnormality by providing a protection device that detects an overload current of the auger motor and controls stop of the motor (for example, Patent Document 1).
[0005]
[Patent Document 1]
Japanese Patent Publication No. Hei 4-24625
[Problems to be solved by the invention]
Generally, when the motor is started, an excessive current (starting current) flows after the shift to the steady operation. However, even if a starting current that is larger than the current during the steady operation flows, each time the motor is started. Shutting down is not practical. Therefore, in Patent Document 1, an operation signal to the auger motor is continuously output with respect to the starting current, and the motor is controlled to stop based on an overload current generated in the operation after the start of the auger motor. are doing.
[0007]
That is, in Patent Document 1, a circuit must be provided to determine the starting current of the auger motor and the overload current during steady operation, which complicates the configuration of the protection device and reduces the risk of failure of the device. Get higher. It is also pointed out that the manufacturing cost is high.
[0008]
[Object of the invention]
SUMMARY OF THE INVENTION The present invention has been proposed in view of the above-mentioned drawbacks inherent in the conventional auger-type ice maker protection device according to the related art, and has been proposed in order to preferably solve the problem. It is an object of the present invention to provide an auger-type ice maker protection device that can be dealt with.
[0009]
[Means for Solving the Problems]
In order to solve the above problems and achieve the intended purpose, a protective device for an auger ice maker according to the present invention includes:
An evaporator connected to a refrigeration system having a compressor is provided on the outer surface, and a freezing casing for freezing the ice making water supplied to the inner wall surface is provided inside the casing so as to be rotatable. An auger screw for transferring the ice frozen to the wall while shaving off the ice, and an auger motor for rotating the auger screw. In the auger-type ice machine configured as above,
An abnormality monitor is started at the same time when the compressor is started, and a protection means for controlling stop of the auger motor when the abnormality is detected during a steady operation of the auger motor is provided.
[0010]
BEST MODE FOR CARRYING OUT THE INVENTION
Next, a protection device for an auger type ice making machine according to the present invention will be described below with reference to the accompanying drawings by taking a preferred embodiment.
[0011]
FIG. 1 shows a schematic configuration of an auger type ice making machine according to an embodiment, in which an evaporating tube 12 as an evaporating unit communicating with a refrigeration system is tightly wound around a cylindrical refrigeration casing 10. Then, the cooling casing 10 is forcibly cooled by circulating the refrigerant through the evaporating pipe 12 during the ice making operation. Further, ice making water is supplied at a predetermined level from an ice making water tank (not shown) to the freezing casing 10, and the ice making operation is started to forcibly cool the freezing casing 10, so that the ice making water gradually freezes from the inner wall surface of the casing. Initially, layered thin ice is being formed.
[0012]
An auger screw 14 is inserted into the inside of the freezing casing 10, a lower shaft portion 14a is rotatably supported by a lower bearing 16 disposed at a lower portion of the freezing casing 10, and an upper shaft portion 14b is An auger screw 14 is rotatably supported by a pressing head 18 disposed inside the upper portion of the freezing casing 10 and is rotated by an auger motor AM disposed below the ice making machine. The auger screw 14 is formed with a helical cutting edge 14 c having an outer diameter slightly smaller than the inner diameter of the freezing casing 10. It is configured to be transported upward while being scraped off by the 14 cutting blades 14c.
[0013]
Then, the flake ice that is transported upward while being scraped off by the auger screw 14 is compressed in the process of passing through the pressing head 18 to remove water, thereby producing compressed ice. The ice is released and stored in a stocker (not shown) arranged on the upper portion of the freezing casing 10.
[0014]
As shown in FIG. 1, the refrigeration system includes a compressor CM and a condenser 20, and a high-temperature vaporized refrigerant (hot gas) compressed by the compressor CM is supplied to the condenser 20 via a pipe 22. It is configured to flow in. The liquefied refrigerant condensed in the condenser 20 flows into the evaporating tube 12 through a capillary tube (not shown), and takes the heat of vaporization from the refrigeration casing 10 by evaporative vaporization to bring the refrigeration casing 10 to zero degree. It is configured to cool below. Further, the vaporized refrigerant after cooling the refrigeration casing 10 returns from the evaporating pipe 12 to the compressor CM via the pipe line 24, and the cycle is repeated thereafter.
[0015]
A pipe line 22 connecting the compressor CM and the condenser 20 includes a bypass pipe 26 that bypasses the condenser 20 and directly communicates with the evaporating pipe 12, and a vaporized refrigerant (hot gas) from the compressor CM. The hot gas valve HV is configured to be supplied to the evaporating tube 12 by switching. That is, for example, when the ice overgrown due to the supercooling of the freezing casing 10 locks the rotation of the auger screw 14, the hot gas valve HV is switched to supply the hot gas to the evaporating pipe 12, and the heat causes The lock can be released.
[0016]
The auger-type ice maker includes a controller 28 that controls the entire electric control, and a protection device 30 that protects the auger motor AM and the auger screw 14 that is driven to rotate by the auger motor AM. FIG. 2 shows a main part of a protection circuit using the protection device 30 of the embodiment. A main board 32 connected to a power supply bus and a control board 34 driven at a low voltage include a transformer TR. Is electrically separated by A main power switch SW is inserted between a power supply line R connected to the power supply of the main board 32 and a connection point D, and a compressor CM and a relay X are connected between the connection point D and the power supply line T. ₂ of the normally open contact _X 2 -a are connected in series. Also between the auger motor AM and the power supply line T connecting to the connection point D, the normally closed contact of the relay _{X 4 X 4} -b, shock relay MS and the normally open contact _X 1 -a relay _{X 1} as a protection means Are connected in series. Between the normally closed contact X ₄ -b connection point D and the relay X _4, the relay X ₃ are interposed in parallel relation between the auger motor AM.
[0017]
The shock relay MS has a built-in current / voltage converter 36 (see FIG. 3) for generating an output voltage corresponding to a change in current of the auger motor AM, and controls the auger motor AM based on the output voltage from the current / voltage converter 36. It has a function to control stop. That is, when an overload equal to or greater than a preset threshold is applied to the auger motor AM during the ice making operation, the overload current flowing through the motor AM is detected as an overload output voltage by the current-voltage converter 36 of the shock relay MS. . When the duration of the overload output voltage exceeds the shock time set in advance for the shock relay MS, the shock relay MS is excited, and the normally open contact MS-a cooperating therewith is turned on (closed). Accordingly, the setting is made such that the energization to the auger motor AM is stopped. When the overload output voltage (overload current) disappears after the shock relay MS operates at the overload output voltage, the shock relay MS automatically returns to the initial state (the normally open contact MS-a is turned off (open)). It is configured to
[0018]
Wherein between the connection point D and the power supply line T, a normally open contact X ₄ -a and the lamp L of the relay X ₄ are connected in series. Also between the normally open contact X ₄ -a and power supply line T of the relay X _4, and recovery timer TM, the Lely X ₄ which are connected in series to the normally closed contact TM-b of the recovery timer TM is parallel Connected in a relationship. Between the normally closed contact TM-b of the connection point D and the recovery timer TM, the normally open contact MS-a of the shock relay MS is in parallel relationship with the normally open contact X ₄ -a relay X ₄ interposed Have been. The return timer TM functions as restart means for restarting the ice maker after an abnormal stop of the ice maker described later, and a predetermined restart time (for example, 30 minutes) is set.
[0019]
Wherein the control board 34, a relay X ₂ for operation control of the relay X ₁ and the compressor CM for operating controls auger motor AM is provided, the relay X ₁ is on the main power switch SW After that, when a predetermined condition (for example, the float switch FS is turned on) is satisfied, the power is supplied to excite the magnet. This control board 34 is connected to the normally open contact X ₃ -a of the relay X _3, in a state capable of energization of the relay X ₂ by the normally open contact X ₃ -a is turned on (closed) It is set as follows. Note that the control board 34 is equipped with a delay timer DTM, the delay timer DTM, the starts counting simultaneously with the start of the auger motor AM, after a predetermined time (e.g. 60 seconds), normally open of the relay X ₃ and closing the contacts (not shown) which interposed between the contact point X ₃ -a relay X _2, it is configured to excite the relay X ₂ (see FIG. 3). In other words, the delay timer DTM during from said relay X ₁ is energized until the relay X ₂ is energized, between the period from the other words auger motor AM is started until the compressor CM is started, predetermined Functions to set a delay time. Further, the delay time set in the delay timer DTM is set to a time sufficient for the auger motor AM to start and then shift to a steady operation, and the starting current of the motor AM is not detected by the current-voltage converter 36. It is like that.
[0020]
The auger-type ice making machine is provided with a water supply valve WV (see FIG. 4) that is turned on and off by a float switch FS built in the ice making water tank, and stores ice making water at a predetermined level in the ice making water tank. Thereby, the ice making water is always supplied to the inside of the freezing casing 10 at a predetermined level.
[0021]
Operation of the embodiment
Next, the operation of the protective device for an auger ice maker according to the embodiment will be described below with reference to FIGS.
[0022]
When the main power switch SW is turned on (ON) in step S1 of FIG. 4 to start the auger type ice making machine, the process proceeds to step S2, where the water supply valve WV is turned on, and water supply to the ice making water tank is started. In step S3, it is determined whether or not the float switch FS is turned on when the water level in the ice making water tank reaches a predetermined level. If the float switch FS is turned on (step S3 is affirmative (YES)), then in step S4. After the water supply valve WV is turned off, the process proceeds to step S5 to start (turn on) the auger motor AM. That is, at the same time the float switch FS is turned in the embodiment, the relay X ₁ is energized in the control board 34 shown in FIG. 2, the normally open contact X ₁ -a is turned on (closed) cooperating therewith, the auger motor Power supply to the AM is started. The energized relay X _3, by the normally open contact X ₃ -a is turned on (closed) for cooperating with this, is also started energization of the delay timer DTM control board 34 at the same time, for example, a delay of 60 seconds Start counting time. However, the relay X ₂ in the control board 34 in this case is not excited, the compressor CM is made remains stopped.
[0023]
After the energization of the auger motor AM is started, when the delay timer DTM counts up in step S6, the process proceeds to step S7, and the compressor CM is started (turned on). That is energized relay X ₂ provided on the control board 34 by the count-up of the delay timer DTM, the normally open contact X ₂ -a which cooperates with this is on (closed), the energization start to the compressor CM Then, the ice making operation is started (step S8). At the same time, energization of the shock relay MS is started, and the built-in current-voltage converter 36 detects a change in the current from the auger motor AM to be monitored, converts this into a voltage change, and outputs it (step). S9). Then, in step S10, it is determined whether or not the overload is applied to the auger motor AM, and whether or not the output voltage from the current-voltage converter 36 is an overload output voltage corresponding to the overload current of the motor AM. If (NO), the steady operation is continued as it is.
[0024]
By the start of the ice making operation, the freezing casing 10 is forcibly cooled by exchanging heat with the refrigerant circulating in the evaporating pipe 12, and the ice making water supplied to the freezing casing 10 from the ice making water tank is removed from the casing inner wall surface. Freezing gradually starts, and layered thin ice is formed. This thin ice is transported upward while being shaved by the cutting blade 14c of the auger screw 14 which is rotationally driven by the auger motor AM prior to the start of the compressor CM. The flake ice transferred by the auger screw 14 is compressed when passing through the pressing head 18 disposed inside the upper portion of the freezing casing 10, and the obtained compressed ice is discharged and stored in a stocker.
[0025]
The ice making water in the ice making water tank decreases due to the continuation of the ice making operation, and it is determined in a step S11 whether or not the float switch FS is turned off. If the step S11 is affirmed (YES), the process proceeds to a step S12. Then, the water supply valve WV is turned on to restart water supply. Then, when it is affirmed (YES) that the float switch FS has been turned on in step S13, the process proceeds to step S14, and the water supply valve WV is turned off.
[0026]
During the operation of the auger-type ice making machine, for example, when flake ice does not pass through the pressing head 18 or when a large mechanical load is applied to the auger motor AM due to ice biting or the like, the current flowing through the motor AM becomes The overload current exceeds the allowable value. This overload current is converted into an overload voltage by the current-voltage converter 36, and the result is affirmative (YES) in step S10. At this time, the process proceeds to step S15 and the machine is completely stopped. That is, when the duration of the output voltage converted into the overload voltage in the current-voltage converter 36 exceeds a predetermined shock time, the shock relay MS is excited. Then the normally open contact MS-a cooperating shock relay MS is turned on (closed), the relay X ₄ is excited, the normally closed contact X ₄ -b cooperating therewith is turned off (opened), the The power supply to the auger motor AM is cut off and the operation is stopped. Further, the relay X ₃ is demagnetized, since the normally open contact X ₃ -a also off cooperating with this, cut off the power supply to the relay X ₂ by the normally closed contact X ₄ -b off, the normally open contact X ₂ -b to this city cooperate is turned off, operation of the compressor CM is stopped. That is, it is possible to prevent the ice making water in the freezing casing 10 from being completely frozen or from being damaged or burnt due to an overload applied to the auger screw 14 or the auger motor AM.
[0027]
Incidentally, the excitation of the relay X _4, normally open contacts X ₄ -a cooperating therewith is turned on (closed), the lamp L is lit, an alarm occurrence of abnormality visually. However, the relay X ₁ this time maintains the energized state, the normally open contact X ₁ -a which cooperates therewith is ON.
[0028]
With the ON operation of the normally open contact MS-a of the shock relay MS, energization of the return timer TM is started, and counting of a set time of, for example, 30 minutes is started. And said recovery timer TM is counted up (after 30 min), the said relay X ₄ are normally closed contact TM-b is opened is deenergized, the normally closed contact X ₄ -b is turned on again for cooperating therewith. Be accompanied no mechanical full stop abnormality as described above, the normally open contact X ₁ -a which the relay X ₁ cooperates with the because they kept on, the normally closed contact X ₄ -b When turned on, the power supply to the auger motor AM is restarted, and the motor AM starts. Then, to start counting the same delay timer DTM and described above, the relay X ₂ and normally open contact X ₂ -a is turned on thereby exciting after 60 seconds, ice-making operation the compressor CM is started automatically Will be resumed. In other words, if the cause of the abnormality is eliminated until the return timer TM counts up, the operation of the auger-type ice maker can be automatically restarted. It is possible to prevent ice from being produced at the start of business due to no ice being produced.
[0029]
In the protection device 30 according to the above-described embodiment, the protection device 30 is operated at the same time as the compressor CM that starts after the auger motor AM starts, and the overload current (overload output voltage) of the auger motor AM is monitored (abnormality monitoring). With this configuration, it is not necessary to use means for determining the starting current of the auger motor AM and the overload current during steady operation, and the device 30 can be simplified and the risk of occurrence of a failure can be reduced. In addition, since the configuration is simplified, the manufacturing cost can be reduced.
[0030]
Here, many of the causes of the overload applied to the auger motor AM are such that the flake ice conveyed by the auger screw 14 does not pass through the pressing head 18 or overgrown due to the overcooling of the freezing casing 10 as described above. The ice is generated after the compressor CM is started and the ice making operation is started, for example, the ice locks the rotation of the auger screw 14. In the embodiment, the overload current (overload output voltage) of the auger motor AM is monitored only during the time when these abnormalities may occur. By avoiding unnecessary monitoring, the apparatus configuration can be simplified.
[0031]
[Modification example]
In the embodiment, the configuration in which the current / voltage converter is incorporated in the shock relay as the protection means has been described. However, the configuration may be such that the converter is provided independently. The protection means is not limited to the shock relay of the embodiment, but may be any other type as long as it can detect the overload output voltage output from the current-voltage converter and stop and control the auger motor. Things can be adopted. Further, the time set in the return timer or the delay timer is not limited to the numerical value of the embodiment, but can be changed to an optimum value according to a use condition or the like. The evaporating section is not limited to the evaporating tube as in the embodiment, but may employ a type in which a refrigerating casing is covered with a cylindrical body and a refrigerant is supplied therebetween, or other various configurations.
[0032]
The monitoring target of the protection means is not limited to the output voltage from the current-voltage converter, but may be a detection value (rotation speed) from a rotation detector that detects the rotation speed of the auger motor. When the ambient temperature at which the auger ice machine is installed is high, when the temperature of the refrigeration casing drops to a predetermined value after the compressor is started, the protection means monitors the abnormality (from the current-voltage converter). Output voltage monitoring, etc.) may be started. That is, when the ambient temperature is high, ice is not produced immediately after the compressor is started, so that there is no problem even if the abnormality monitoring is started after the start of the compressor.
[0033]
【The invention's effect】
As described above, the protection device for an auger-type ice making machine according to the first aspect of the present invention is configured to monitor the abnormality at the same time as the start of the compressor. In addition, there is no need to provide a means for discriminating an overload current, a change in the number of revolutions, and the like during a steady operation, and the apparatus can be simplified to reduce the risk of occurrence of a failure. Further, since the configuration is simplified, there is an advantage that the manufacturing cost can be reduced.
[0034]
In the protection device for an auger-type ice making machine according to the second aspect of the present invention, since the overload current of the auger motor is monitored together with the start of the compressor that starts after the auger motor is started, the starting current of the auger motor and the steady-state operation during steady operation There is no need to provide a means for determining an overload current, and the device can be simplified and the risk of occurrence of a failure can be reduced. Further, since the configuration is simplified, there is an advantage that the manufacturing cost can be reduced.
[Brief description of the drawings]
FIG. 1 is a schematic view showing an auger type ice making machine employing a protection device according to a preferred embodiment of the present invention.
FIG. 2 is an electric circuit diagram of the protection device according to the embodiment.
FIG. 3 is a timing chart when the auger ice maker according to the embodiment is operated.
FIG. 4 is a flow chart when the auger ice maker according to the embodiment is operated.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 Refrigeration casing, 12 Evaporation tube (evaporation part), 14 Auger screw 36 Current-voltage converter, AM auger motor, CM compressor MS Shock relay (Protection means)

Claims (2)

An evaporator (12) connected to a refrigeration system having a compressor (CM) is provided on the outer surface, and a freezing casing (10) for freezing the ice making water supplied inside to an inner wall surface; An auger screw (14) rotatably disposed in the inside of the housing and transferring the ice frozen on the inner wall surface of the casing while shaving off the auger screw; and an auger motor (AM) for rotating and driving the auger screw (14). An auger-type ice maker configured to start the ice making operation by starting the compressor (CM) after rotating the auger screw (14) by (AM).
An abnormality monitor is started when the compressor (CM) is started, and a protection means (MS) for controlling stop of the auger motor (AM) when the abnormality is detected during steady operation of the auger motor (AM) is detected. An auger-type ice maker protection device. A current-voltage converter (36) for generating an output voltage corresponding to a change in current of the auger motor (AM); ) Is started, and when the output voltage corresponding to the overload current generated during the steady operation of the auger motor (AM) is detected, the motor (AM) is set to stop control. The protection device for an auger ice maker according to claim 1.

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