JPH08261571A - Method for actuating compression type freezer - Google Patents

Abstract

PURPOSE: To detect so-called 'sleeping state' of refrigerant, set a required minimum number of electrical energization times for a heater, and prevent surely a liquid compression of a compressor from being produced, while an inherent function of a compression type freezing device is not damaged. CONSTITUTION: There are provided a closed container 1 for a compressor, a circulating scroll 2, a fixed scroll 3, a suction pipe passage 4, a discharging pipe passage 5, a motor 6, a power supply circuit 7 for the compressor, a control device 8 and a heater 9. The heater 9 is electrically energized only in the case that a duration time in which the compressor is being stopped continues more than a specified period of time, and then it is energized in a normal rotation and set into the normal operation.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for starting a compression refrigeration system.

[0002]

2. Description of the Related Art Liquid refrigerant stagnation occurs in a suction line of a compressor, which occurs when the compressor is kept at a low temperature while the refrigeration cycle of an air conditioner or the like is stopped for a long time, so that liquid compression occurs at startup. In order to prevent excessive shaft torque and damage to the compressor, the compressor power circuit of the refrigeration system starts in reverse rotation only at the first start after switching on, and gas is discharged from the discharge port. The liquid refrigerant was discharged from the suction suction port and pushed back to stop the liquid refrigerant sunk in the suction pipe line, and then stopped again, and then the normal rotation was started again to suck the gas to prevent the liquid compression. In the start-up during the on / off operation according to the control command of the refrigerating device, the start-up is immediately started in the forward rotation to reduce the number of reverse rotating operations so as not to impair the original capacity of the compression refrigerating device.
A method of starting such a compression type refrigerating apparatus is known, for example, from Japanese Patent Laid-Open No. 61-213556.

[0003]

However, in the above-mentioned method, for example, in the case of an air conditioner, the compressor is controlled in a low temperature outside air for a long time depending on the heat load in the room being controlled and the air conditioning setting of the user. It may be stopped by a command. In this case, there is a problem in that there is a high possibility that liquid compression of the compressor will occur and the compressor will be damaged.

In view of the above-mentioned problems, the present invention relates to a starting method for surely preventing liquid compression of a compressor while keeping the original capacity of the compression type refrigerating device by minimizing the number of times the heater is energized. is there.

[0005]

In order to solve the above problems, the invention according to claim 1 is a compression type refrigerating apparatus using a positive displacement compressor in which a compressor is heated by energizing a heater. If the stop time is over a certain period of time, energize the heater and stop for a predetermined period of time, then stop at normal rotation and start normal operation.If it is less than a certain time, start immediately at forward rotation. And a method for starting a compression type refrigerating apparatus.

The invention according to claim 2 is a compression type refrigerating apparatus using a positive displacement compressor in which the compressor is warmed by energizing the heater. The method of starting the compression refrigeration system is characterized in that it is carried out when the temperature of the suction pipe line is lower than a certain temperature for a certain period of time or longer, and when starting in other states, it is immediately started in forward rotation. is there.

According to a third aspect of the present invention, in a compression type refrigerating apparatus using a positive displacement compressor in which a compressor is heated by energizing a heater, energization of the heater is carried by a compressor in a stopped state. The method for starting the compression type refrigerating apparatus is characterized in that it is performed when the state where the ambient temperature of the device is lower than a certain temperature is maintained for a certain period of time or longer, and when starting in other states, it is immediately started in forward rotation. It is a thing.

According to a fourth aspect of the present invention, in a compression type refrigerating apparatus using a positive displacement compressor in which a compressor is warmed by energizing a heater, energization of the heater is performed by a liquid provided inside the compressor. The method is performed when the amount of liquid refrigerant in the compressor is detected by the refrigerant detection means above a certain level, and when starting in any other state, it is started immediately in forward rotation and is a method for starting a compression refrigerating device. .

Further, the invention according to claim 5 is a compression type refrigerating apparatus using a positive displacement compressor in which a compressor is warmed by energizing a heater, when the compressor is started in forward rotation. When the current value exceeds a certain level, the heater is energized, and when starting in any other state, it is started immediately in forward rotation.

[0010]

The operation of the above means is as follows. In the invention according to claim 1, when the compressor of the refrigeration system is stopped by the control device, the control device measures the time during which the compressor is stopped. The control device determines whether the time the compressor has been stopped when the compressor is started is equal to or longer than a preset time. When it is determined that the compressor has been stopped for more than the preset time, the control device energizes the heater, and the heat generated by the heater causes the liquefied liquid refrigerant to return to the gas. After that, the control device starts the normal rotation after stopping the energization of the heater.
In cases other than the above, the compressor is started immediately after normal rotation.

Further, in the invention according to claim 2, when the control device tries to start the compressor, whether the temperature of the portion representative of the compressor is equal to or lower than a preset temperature for a preset time or longer. Make a decision. If it is determined that the temperature of the part that represents the compressor is below the preset temperature for more than the set time,
The control device energizes the heater and returns the liquefied liquid refrigerant to gas by the heat generated by the heater. After that, the control device starts the normal rotation after stopping the energization of the heater. In cases other than the above, the compressor is started immediately after normal rotation.

Further, in the invention according to claim 3, when the control device attempts to start the compressor, a state in which the ambient temperature of the device equipped with the compressor is equal to or lower than a preset temperature is equal to or longer than a set time. Determine if it was continued. If the controller determines that the ambient temperature of the equipment in which the compressor is installed is below the preset temperature for more than the set time, the controller energizes the heater and sleeps due to the heat generated by the heater. Return the saliva refrigerant to gas. After that, the control device starts the normal rotation after stopping the energization of the heater. In cases other than the above, the compressor is started immediately after normal rotation.

Further, in the invention according to claim 4, the control device determines whether or not the liquid refrigerant detecting means provided inside the compressor or the suction pipe detects the liquid refrigerant when the compressor is started. To do. When it is determined that the liquid refrigerant has been detected, the control device energizes the heater, and the heat generated by the heater causes the liquefied liquid refrigerant to return to the gas. After that, the control device starts the normal rotation after stopping the energization of the heater. In cases other than the above, the compressor is started immediately after normal rotation.

Further, in the invention according to claim 5, the control device determines whether or not the compressor starting current immediately after the compressor is started in the normal rotation is equal to or higher than a certain level. When it is determined that the compressor starting current is above a certain level, the controller immediately stops the compressor and then energizes the heater, and the heat generated by the heater causes the liquefied liquid refrigerant to return to the gas. After that, the control device starts the normal rotation after stopping the energization of the heater.
In cases other than the above, the compressor is started immediately after normal rotation.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

(Embodiment 1) First, Embodiment 1 of the present invention will be described with reference to FIG. FIG. 1 shows a compression type refrigerator of the present invention. Reference numeral 1 is a compressor closed container, 2 is an orbiting scroll, 3 is a fixed scroll, 4 is a suction pipeline, 5 is a discharge pipeline, 6 is a motor, 7 is a compressor power supply circuit, 8 is a controller, and 9 is a heater. .

The control operation in the above configuration will be described. When the compressor is stopped by the controller 8 of the refrigeration system, the controller 8 measures the time T while the compressor is stopped. The control device 8 sets the preset time T1 to the time T when the compressor is stopped when the compressor is started.
Determine if it is above. When it is determined that the time T during which the compressor has been stopped is equal to or longer than the preset time T1, the control device 8 energizes the heater 9, and the heat generated by the heater 9 causes the liquefied liquid refrigerant to fall. Return to gas. After that, the controller 8 stops the energization of the heater 9 and then starts the normal rotation. In cases other than the above, for example, the compressor is started by turning on / off the compressor in a short time immediately after the normal rotation.

As is clear from the above operation, the stagnation of the refrigerant is detected by always detecting the stop time of the compressor, and the number of times the heater is energized is reduced to the necessary minimum so that the original capacity of the compression refrigeration system is not impaired. In addition, it is possible to reliably prevent liquid compression at a relatively low cost.

(Second Embodiment) Next, a second embodiment of the present invention will be described with reference to FIG. FIG. 2 shows a compression refrigerator according to the present invention. The same parts as those in FIG. 1 are designated by the same reference numerals and the description thereof will be omitted.

In FIG. 2, reference numeral 10 is a temperature detecting means provided in the suction pipe line. The control operation in the above configuration will be described.

When the control device 8 attempts to start the compressor, the temperature H of the suction pipe temperature detecting means 10 provided in the suction pipe 4 remains below the preset temperature H2 for a set time T2 or longer. Determine if it was done. When it is determined that the temperature H of the suction line temperature detecting means 10 is equal to or lower than the preset temperature H2 for the set time T2 or longer, the control device 8 energizes the heater 9 and heats the heater 9. The heat causes the liquid refrigerant that has fallen asleep to be returned to gas. After that, the controller 8 stops the energization of the heater 9 and then starts the normal rotation. In cases other than the above, the compressor is started immediately after normal rotation.

As is clear from the above operation, the suction pipe temperature detecting means 10 detects the time during which the suction pipe 4 is below the set temperature while the compressor is stopped to detect the stagnation of the refrigerant, It is possible to reliably prevent the liquid compression while keeping the original capacity of the compression type refrigerating device by reducing the number of energization of the heater 9 to the necessary minimum.

(Third Embodiment) Next, a third embodiment of the present invention will be described with reference to FIG. 3 shows a compression type refrigerator according to the present invention. The same parts as those in FIG. 1 are designated by the same reference numerals and the description thereof will be omitted.

Reference numeral 11 is an outer box of an apparatus in which the compressor of the present invention is mounted, and 12 is an ambient temperature detecting means of the outer box 11.

The control operation in the above configuration will be described. The controller 8 detects the ambient temperature of the ambient temperature of the outer casing 11 when the compressor is stopped when the compressor is about to start.
It is determined whether or not the temperature H is lower than the preset temperature H3 for a set time T3 or longer. When it is determined that the temperature H of the ambient temperature detecting means 12 is equal to or lower than the preset temperature H3 for the set time T3 or longer, the control device 8 energizes the heater 9 to generate heat by the heater 9. , Return the lying liquid refrigerant to gas. After that, the controller 8 stops the energization of the heater 9 and then starts the normal rotation. In cases other than the above, the compressor is started immediately after normal rotation.

As is clear from the above operation, the ambient temperature detecting means 12 detects the time during which the ambient temperature of the outer casing 11 when the compressor is stopped is below the set temperature, thereby detecting the stagnation of the refrigerant, It is possible to reliably prevent the liquid compression while keeping the original capacity of the compression type refrigerating device by reducing the number of energization of the heater 9 to the necessary minimum.

(Fourth Embodiment) Next, a fourth embodiment of the present invention will be described with reference to FIG. FIG. 4 shows the compression refrigerator of the present invention, and the same parts as those shown in FIG.

Reference numeral 13 is a float switch provided in the suction pipe line 4 as a liquid refrigerant surface detecting means for detecting the liquid refrigerant surface.

The control operation in the above configuration will be described. When the control device 8 attempts to start the compressor, it determines whether the float switch 13 provided in the suction pipe line 4 detects the liquid refrigerant surface. When it is determined that the float switch 13 detects the liquid refrigerant surface, the control device 8 energizes the heater 9 to return the liquefied liquid refrigerant to gas by the heat generated by the heater 9. Then the control device 8
Starts the normal rotation after stopping the energization of the heater 9. In cases other than the above, the compressor is started immediately after normal rotation.

As is clear from the above operation, the suction pipe line 4
By directly detecting the stagnation of the refrigerant by the float switch 13 provided as the liquid refrigerant surface detecting means,
It is possible to reliably prevent the liquid compression while keeping the original capacity of the compression type refrigerating device by reducing the number of energization of the heater 9 to the necessary minimum.

(Fifth Embodiment) Next, a fifth embodiment of the present invention will be described with reference to FIG. FIG. 5 shows a compression refrigerator according to the present invention. The same parts as those in FIG. 1 are designated by the same reference numerals and the description thereof will be omitted.

Reference numeral 14 is a compressor current detecting means for detecting the current value of the electric power supplied to the compressor motor 6.

The control operation in the above configuration will be described. The controller 8 determines whether the compressor starting current C immediately after starting the compressor in the normal rotation is equal to or higher than a constant level C1. When it is determined that the compressor starting current C is equal to or higher than the constant level C1, the compressor current detection means 14 detects it and the controller 8
Immediately stops the compressor and then energizes the heater 9 to return the liquefied liquid refrigerant to gas by the heat generated by the heater 9. After that, the controller 8 stops the energization of the heater 9 and then starts the normal rotation. In cases other than the above, the compressor is started immediately after normal rotation.

As is apparent from the above operation, paying attention to the fact that the compressor current increases during liquid compression, the compressor current at the time of normal rotation start is detected by the compressor current detecting means 14 and the stagnation is detected. It is possible to reliably prevent the liquid compression while minimizing the number of energization of the heater 9 so as not to impair the original capacity of the compression type refrigerating apparatus.

[0035]

As is apparent from the above embodiment, according to the invention as set forth in claim 1, the stagnation of the refrigerant is detected by constantly detecting the stop time of the compressor, and the number of times of energizing the heater is required. It is possible to reliably prevent liquid compression at a relatively low cost while minimizing the original capacity of the compression type refrigerating device without impairing it.

Further, in the invention according to claim 2, the stagnation of the refrigerant is detected by detecting the time during which the suction pipe line during the stop of the compressor is below the set temperature, and the number of times the heater is energized is required. It is possible to surely prevent liquid compression while minimizing the original capacity of the compression type refrigeration system as much as possible.

In the invention according to claim 3, the stagnation of the refrigerant is detected by detecting the time when the ambient temperature of the outer case while the compressor is stopped is below the set temperature, and the number of times the heater is energized is detected. It is possible to surely prevent liquid compression while minimizing the above so as not to impair the original capability of the compression type refrigeration system.

Further, in the invention according to claim 4, the liquid refrigerant surface detection means provided in the suction pipe directly detects the stagnation of the refrigerant so that the number of times of energization of the heater is reduced to the necessary minimum and the compression type refrigerating apparatus is provided. Liquid compression can be reliably prevented while not impairing the original ability.

Further, in the invention according to claim 5, paying attention to the fact that the compressor current increases at the time of liquid compression, the compressor current at the time of the normal rotation start is detected by the current detecting means to detect the stagnation. It is possible to reliably prevent the liquid compression while minimizing the number of times the heater is energized so as not to impair the original capability of the compression type refrigeration system.

[Brief description of drawings]

FIG. 1 is an explanatory block diagram of a compression type refrigerator according to a first embodiment of the present invention.

FIG. 2 is an explanatory block diagram of a compression type refrigerator according to the second embodiment.

FIG. 3 is an explanatory block diagram of a compression refrigerator according to the third embodiment.

FIG. 4 is an explanatory block diagram of a compression refrigerator according to the fourth embodiment.

FIG. 5 is an explanatory block diagram of a compression refrigerator according to the fifth embodiment.

[Explanation of symbols]

 1 Compressor Airtight Container 2 Orbiting Scroll 3 Fixed Scroll 4 Suction Pipeline 5 Discharge Pipeline 6 Motor 7 Compressor Power Supply Circuit 8 Control Device 9 Heater 10 Suction Pipeline Temperature Detecting Device 11 Outer Box 12 Ambient Temperature Detecting Device 13 Liquid Refrigerant Surface detecting means 14 Compressor current detecting means

Claims (5)

[Claims] 1. A compression type refrigerating apparatus using a positive displacement compressor in which a compressor is heated by energizing a heater, and when the compressor is stopped for a certain time or longer, the heater is energized for a predetermined time. A method for starting a compression refrigerating device, which is characterized by stopping after operation, starting at normal rotation to start normal operation, and immediately starting at normal rotation if it is less than a certain time. 2. In a compression type refrigeration system using a positive displacement compressor in which a compressor is warmed by energizing a heater, energizing the heater is such that the temperature of the compressor and the suction pipe line when the compressor is stopped are higher than a constant temperature. A method for starting a compression type refrigerating apparatus, which is performed when a low state is maintained for a certain period of time or longer, and when starting in other states, immediately starting in forward rotation. 3. In a compression type refrigerating apparatus using a positive displacement compressor in which a compressor is warmed by energizing a heater, energization of the heater is carried out when the ambient temperature of the apparatus in which the compressor is stopped is mounted. A method for starting a compression refrigeration apparatus, which is performed when a temperature lower than a certain temperature is maintained for a certain period of time or longer, and when starting in other states, immediately starting in normal rotation. 4. In a compression type refrigerating apparatus using a positive displacement compressor in which a compressor is heated by energizing a heater, the heater is energized by a liquid refrigerant detecting means provided inside the compressor. A method for starting a compression refrigerating device, which is performed when the amount of refrigerant is detected above a certain level, and is immediately started in normal rotation when starting in other states. 5. A compression type refrigerating apparatus using a positive displacement compressor in which a compressor is warmed by energizing a heater, when the compressor current value when the compressor is started in a normal rotation exceeds a certain level. The method for starting a compression refrigerating device is characterized in that the heater is energized, and when starting in other states, the heater is immediately started in forward rotation.