JPH0830634B2 - Abnormality display device of constant temperature machine - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an interior of a refrigerator by alternately operating and stopping an electric compressor that rotatably drives and compresses a refrigerant circulated through a condenser and an evaporator in response to power supply. The present invention relates to a constant temperature machine such as a refrigerator or a freezer whose temperature is maintained between an upper limit temperature and a lower limit temperature, and particularly relates to an abnormality display device that displays the abnormality when an abnormality occurs in the constant temperature machine.

[0002]

2. Description of the Related Art Conventionally, this type of anomaly display device uses an electric power cut-off means provided in an electric power supply passage of an electric compressor when the load of the electric compressor becomes excessive due to various abnormalities of a thermostatic machine. The power supply to the compressor was cut off, and in response to the cutoff of the power supply, these various abnormalities were displayed by a single error code on the display.

[0003]

However, in the above-mentioned conventional apparatus, since the same error code is displayed for different abnormalities of the thermostat, it is difficult to find the location of the abnormality. Therefore, there is a problem in that it takes time to repair an abnormality of the thermostatic chamber, the repair cost increases, and the operating rate of the thermostatic chamber decreases. SUMMARY OF THE INVENTION The present invention is intended to solve the above problems, and an object of the present invention is to provide an abnormality display device for a thermostatic chamber that can easily find the cause of abnormality in the thermostatic chamber.

[0004]

In order to achieve the above-mentioned object, the structural feature of the invention according to claim 1 is that the refrigerant which is rotationally driven and compressed according to the power supply is compressed by the condenser 1a and the evaporator. An electric compressor 1c that circulates through 1b ,
Usually, the compressor 1 is provided in the power supply path of the electric compressor 1c.
c , a power cutoff means for cutting off the power supply to the compressor 1c when the load on the compressor 1c is excessive.
1d , an inside temperature detecting means 2a for detecting the temperature of the inside 2 cooled by the evaporator 1b, and an inside temperature detecting means 2a.
A constant temperature machine having an operation control means 2b for controlling the alternating operation of the operation and stop of the electric compressor 1c on the basis of the temperature detected by the above to maintain the internal cold storage temperature between a predetermined upper limit temperature and a lower limit temperature. , Electric compressor by operation control means 2b
Time measuring means 3 for measuring the time from the start of operation of 1c
Then, when the power cutoff means 1d cuts off the power supply to the electric compressor 1c , the time measuring means 3 finishes measuring the predetermined time.
Abnormality occurred in the electric compressor 1c on condition that it is not
It is determined that the time measurement means 3 has measured the predetermined time.
Condenser 1a, evaporator 1b, etc. on condition that they have been completed
Abnormality type that determines whether an abnormality has occurred in the refrigerant piping system
It was judged by the class judging means 4 and the abnormality type judging means 4.
The abnormality of the electric compressor 1c and the abnormality of the refrigerant piping system are distinguished from each other.
The display means 5 for displaying separately is provided.

The structural feature of the invention according to claim 2 is that the condenser 1a and the evaporator 1 of the invention according to claim 1 are characterized.
b, electric compressor 1c, power cutoff means 1d, internal temperature sensor
Equipped with a motor 2a and operation control means 2b
Select hot gas from downstream of compressor 1c to upstream of evaporator 1b
The electromagnetic valve 1e supplied selectively and the temperature of the evaporator 1b
Evaporator temperature detecting means 6a for detecting and operation control means 2b
The electric compressor 1c is operated by the
Operate the dynamic compressor 1c and turn on the electromagnetic valve 1e.
Temperature detected by the evaporator temperature detecting means 6a
When the temperature rises to a predetermined temperature, the solenoid valve 1e is turned off.
The evaporator 1b is removed while the electromagnetic valve 1e is turned on.
In the constant temperature machine provided with the defrosting control means 6b for frosting,
When measuring the time from the start of defrosting by the frost control means 6b
Interval measuring means 7 and power cutoff means 1d to electric compressor 1c
When the power supply to the
The same electric compressor 1c on condition that the measurement of
It is determined that an abnormality has occurred in the
Electromagnetic valve 1 on condition that time measurement has been completed
e, hot gas piping system such as evaporator 1b or evaporator temperature
Abnormality type that determines that an abnormality has occurred in the degree detection means 6a
It was judged by the class judging means 8 and the abnormality type judging means 8.
Abnormality of electric compressor 1c and hoggas piping system or evaporator temperature
Display unit 5 for distinguishing and displaying the abnormality of the degree detection unit 6a
It has been established.

[0006]

In the invention according to claim 1 configured as described above, when an abnormality occurs in the constant temperature machine during the cooling operation of the constant temperature machine and the load of the electric compressor 1c becomes excessive,
With power interruption means 1d cuts off the power supply to the electric compressor 1c, in response to the interruption of power supply to the electric compressor 1c, abnormal kind determination means 4 of the electric compressor 1c by the operation control means 2b The type of abnormality is determined according to the time from the start of operation . The abnormality that occurs immediately after the start of the electric compressor 1c is due to the locking of the motor of the electric compressor 1 or the like.
Therefore, the abnormality type determination means 4 is
When the time measuring means 3 for measuring the time from the start of operation is at a predetermined time
The electric compressor 1 provided that the measurement between
It is determined that an abnormality has occurred in c. Further, since the abnormality that occurs thereafter is an abnormality in the piping system of the refrigerant such as clogging of the condenser 2 and the evaporator 3 , the abnormality type determination means.
In No. 4, the time measuring means 3 has finished measuring the predetermined time.
Under this condition, it is determined that the refrigerant piping system is abnormal.
Then, the display unit 5 displays the abnormality of the electric compressor 1c and the distribution of the refrigerant.
It is displayed separately from abnormal tubing.

Thus, according to the first aspect of the invention, the user can generate the electric pressure generated during the cooling operation of the thermostatic machine.
Since it is possible to accurately grasp the abnormality of the compressor 1c and the abnormality of the piping system of the refrigerant by the display means 5, it is possible to immediately deal with the abnormality. Therefore, the repair time of the thermostatic machine can be shortened, the repair cost can be reduced, and the operation stop time due to the occurrence of an abnormality can be shortened to improve the operating rate of the thermostatic machine.

[0008] In the invention of claim 2 constructed as described above, when the defrosting of the constant temperature machine abnormality in a constant temperature machine generated load of the electric compressor 1c becomes excessive, the power shut-off with means 1d cuts off the power supply to the electric compressor 1c, in response to a power cut-off to the electric compressor 1c, abnormal kind determination means 8 or defrosting initiation by the defrosting control unit 6b
The type of abnormality is determined according to these times . Since the abnormality that occurs immediately after the start of defrosting is due to the locking of the motor of the electric compressor 1c or the like , the abnormality type determining means 8 is
The time measuring means 7 for measuring the time from the start
On the condition that the measurement is not finished, the electric compressor 1c
Determine that an abnormality has occurred. Further, the abnormality that occurs during a subsequent defrosting, the solenoid valve 1e, etc. Ri because Dzuma such evaporator 3, the abnormality of the piping system of the hot gas, or because it is abnormal for the evaporator temperature detecting means 3a, abnormal kind determination
In the means 4, the time measuring means 7 finishes measuring the predetermined time.
Hot gas piping system or evaporator temperature
It is determined that the detection means 3a is abnormal. And display hand
Stage 5 is abnormality of electric compressor 1c and hot gas piping system or
It is displayed separately from the abnormality of the evaporator temperature detecting means 6a.

Thus, according to the second aspect of the invention, the user can generate the electric power generated in the thermostat even during defrosting.
Abnormality of dynamic compressor 1c and hot gas piping system or evaporator temperature
Accurately grasp the abnormality of the degree detection means 6a by the display means 5.
It is possible to deal with abnormalities immediately.
Wear. This shortens the time required to repair the thermostat and
And the downtime due to an abnormal occurrence.
The operating rate of the thermostat can be improved by shortening.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 2 schematically shows an entire thermostatic machine such as a refrigerator and a freezer in a block diagram. This thermostat is provided with a cooling device including an electric compressor 11, a condenser 12, and a throttle 13 provided outside the refrigerator and an evaporator 14 provided inside the refrigerator, and the refrigerant pressure-fed from the electric compressor 11 is supplied in this order. It is circulated and the inside of the refrigerator is cooled by the evaporator 14. The electric compressor 11 has a relay 16 from an AC power supply 15.
Power is supplied through the normally open contacts X11, X12 and the overload relay 17. Normally open contacts X11, X
The relay 12 is turned on / off by energizing / de-energizing the coil X1 of the relay 16. The overload relay 17
The overload relay 17 is normally turned on when a thermo switch (not shown) provided in the case of the electric compressor 11 is turned on and off, and the overload relay 17 is normally turned on. When the case temperature of the machine 11 rises and the thermo switch is turned off, the thermo switch is turned off and the power supply path is cut off.

An electromagnetic valve 18 is provided between the discharge port of the electric compressor 11 and the upstream of the evaporator 14, and hot gas from the electric compressor 11 is supplied to the evaporator 14 when the valve 18 is in conduction. It is supposed to be done. Electromagnetic valve 1
Reference numeral 8 is connected to the power supply path from the AC power source 15 via the normally open contacts X21 and X22 of the relay 19, and is set to a conductive state when power is supplied and a non-conductive state when power is not supplied. It Relay 19 normally open contacts X21, X22
Is turned on / off by energizing / de-energizing the coil X2 of the relay 19.

The coils X1 and X2 of the relays 16 and 19 and the overload relay 17 are connected to a microcomputer 20. The microcomputer 2 includes a transformer 2
A DC voltage is supplied from a power supply circuit 22 connected to the AC power supply 15 through the microcomputer 1, and the microcomputer 20 operates by supplying the DC voltage. The DC voltage is also connected to a display control circuit 25, a display 26, etc. described later.

The microcomputer 20 has a bus 20a.
ROM20b, CPU20c, R respectively connected to
The AM 20d, the first timer 20e, the second timer 20f, the I / O 20g, and the like. ROM 20b
3 stores a program corresponding to the flowcharts of FIGS. 3 to 6, the CPU 20c executes the program, and the RAM 20d temporarily stores variables necessary for executing the program. The first timer 20e determines the defrost cycle, and counts up after a predetermined time (for example, 6 to 8 hours) from the start of operation. The second timer 20f is used for detecting an abnormality in the electric compressor 11, and counts up 30 seconds after the start of operation. The I / O 20g transmits / receives a signal to / from the outside. The I / O 20g includes, in addition to the coils X1 and X2 of the relays 16 and 19, an internal temperature sensor 23, a defrost thermoswitch 24, and a display control circuit 25. And a display 26 is connected.

The inside temperature sensor 23 is provided inside the refrigerator or the freezer, and detects the inside temperature T and outputs a detection signal indicating the same temperature T. The defrost thermoswitch 24 is constituted by a temperature-sensitive switch attached to the evaporator 14, and is normally turned on (during repeated operation of the operation and stop of the cooling device), and the evaporator 14 completes defrosting. It turns off for the first time when the temperature rises to a certain temperature, and outputs a signal indicating this on / off state. Display 2
6 is composed of a liquid crystal display or the like for displaying alphanumeric characters, and is controlled by the display control circuit 25 to control the temperature T in the refrigerator.
And error codes E1 to E3 indicating the type of abnormality are displayed.

Next, the operation of the embodiment configured as described above will be described. When a power switch (not shown) is turned on, a DC voltage is supplied from the power circuit 22 to the CPU 20c, the CPU 20c starts executing the program in step 100 of FIG. 3, and the cooling flag CFLG in step 101.
The variables in the RAM 30d are set to initial values including the initial setting of "0" to "0".

First, the case where no abnormality has occurred in the thermostat will be described.
The circulation process consisting of 2 to 107 is repeatedly executed. In the circulation processing, the CPU 20c first executes step 10
At step 2, the operation of the first timer 20e is started, and step 1
At 03, it is determined whether or not the first timer 20e is counting up (whether or not 6 to 8 hours have elapsed from the start of the operation). In this case, since the first timer 20e has just started to operate, it is determined to be "NO" in the step 103, and the CPU 20c determines that the step 1
At 04, it is determined to be "YES" based on the cooling flag CFLG initially set to "0", and at step 105, the process of "operation stop routine" is executed.

This "shutdown routine" is shown in detail in FIG. 4, and the CPU 20c starts its execution at step 110, and at step 111 the inside temperature sensor 23.
Whether a temperature T is equal to or higher than a predetermined upper limit temperature TH (eg, −2 ° C. in a refrigerator, −17 ° C. in a freezer) by inputting a detection signal indicating the temperature T in the refrigerator. To determine. In the thermostat, since the internal temperature T is equal to or higher than the upper limit temperature TH immediately after the power switch is turned on, the CPU 20c causes “YES” in step 111.
Then, in step 112, the coil X1 of the relay 16 is determined.
Power on and the cooling flag CFLG is set to "1" in step 113.
In step 114, the operation of the second timer 20f is started, and in step 115, the process of the "operation stop routine" is ended. As a result, the normally open contacts X11, X12 of the relay 16 are set to the ON state, and the electric compressor 11
Power from the AC power supply 15 is supplied to the compressor 1
1 starts the operation, the cold refrigerant is supplied to the evaporator 14, and the inside of the refrigerator begins to be cooled.

Next, the CPU 20c returns the program to step 103 in FIG.
After the determination "O", it is determined "NO" based on the cooling flag CFLG changed to "1" in step 104,
In step 106, the process of "cooling operation routine" is executed. The details of this "cooling operation routine" are shown in FIG. 5, and the CPU 20c starts its execution in step 120, and the inside temperature T detected by the inside temperature sensor 23 in step 121 is the lower limit temperature. Less than TL (for example,
(-4 ° C in a refrigerator, -19 ° C in a freezer)
Is determined. In this case, since the inside of the refrigerator has just started to be cooled and the temperature inside the refrigerator is equal to or higher than the lower limit temperature TL, the CPU 20c causes “NO” in step 121.
It is determined to be “NO” in Step 122 based on that the overload relay 17 is turned on, and Step 1
The display data indicating the internal temperature T is displayed by the display control circuit 2
5, and the processing of this "cooling operation routine" is ended in step 124. The display control circuit 25 controls the display device 26 based on the display data, and the display device 26 numerically displays the internal temperature T (for example, "-1.5.
° C ").

After completion of the "cooling operation routine", the CP
U20c returns the program to step 103 of FIG.
After that, the circulation process including steps 103, 104 and 106 is repeatedly executed. During this circulation process, the coil X1 of the relay 16 is continuously energized, so that the inside of the cold storage is continuously cooled by the evaporator 14, and the internal cold storage temperature T gradually drops. Further, the inside temperature T continues to be displayed on the display 26.

In this way, when the internal temperature T drops and falls below the lower limit temperature TL, the CPU 20c makes a "YES" determination at step 121 of FIG. 5 and at step 125 energizes the coil X1 of the relay 16. Cancel, Step 1
At step 26, the cooling flag CFLG is changed to "0", and at step 124, the processing of this "cooling operation routine" ends. As a result, the normally open contacts X11, X12 of the relay 16 are set to the OFF state, the supply of electric power from the AC power supply 15 to the electric compressor 11 is stopped, and the compressor 11 is stopped.
The cooling of the inside of the refrigerator by the evaporator 14 is stopped, and the temperature T inside the refrigerator begins to rise.

Next, the program is step 103 in FIG.
After the determination of “NO” in step 103, it is determined to be “YES” based on the cooling flag CFLG changed to “0” in step 104. Therefore, the circulation process including steps 103 to 105 is performed. Will be executed repeatedly. In this case, in the "operation stop routine of step 105" (FIG. 4), the CPU 20c determines "NO" in step 111 until the internal temperature T becomes equal to or higher than the upper limit temperature TH, and in step 116, the internal temperature. The display data representing T is output to the display control circuit 25. As a result, in this case, the operation of the electric compressor 11 is stopped, the temperature T in the refrigerator gradually rises, and the temperature T in the refrigerator is continuously displayed as a number on the display 26.

When the internal temperature T becomes equal to or higher than the upper limit temperature TH, the CPU 20c causes the "operation stop routine" (FIG. 4).
In step 111, it is determined to be “YES”, and the process in step 112 starts cooling the inside of the refrigerator. By the circulation processing including such steps 103 to 106 (FIG. 3), the operation and stop of the cooling device are repeatedly controlled, and the internal temperature T is maintained between the lower limit temperature TL and the upper limit temperature TH.

On the other hand, during the circulation process consisting of the steps 103 to 106, after 6 to 8 hours have passed, the first timer 20e
Is counted up, the CPU 20c proceeds to step 10
It is determined to be "YES" in step 3, and the processing of the "defrosting routine" is executed in step 107. The details of this "defrosting routine" are shown in FIG.
The execution is started at 40, the operation of the second timer 20f is started at step 141, and the coil X1 of the relay 16 is energized at step 142. As a result, even if the constant temperature machine is at rest and the electric compressor 11 is stopped,
The compressor 11 starts operating.

Next, the CPU 20c determines "NO" based on the overload relay 17 being in the ON state in step 143, and displays the display data for displaying that the defrosting is in progress in step 144. It is output to the display control circuit 25, and in step 145, the coil X2 of the relay 19 is energized. As a result, the display control circuit 25 controls the display device 26 based on the display data, and the display device displays the fact that defrosting is in progress (for example, "dF"). Further, since the normally-open contacts X21, X22 of the relay 19 are set to the ON state, electric power is supplied to the electromagnetic valve 18 from the AC power supply 15, the valve 18 is turned on, and the hot gas from the compressor 11 is electromagnetized. It is supplied upstream of the evaporator 14 via a valve 18. As a result, the temperature of the evaporator 14 starts to rise, and the frost attached to the evaporator 14 is removed.

After the processing of step 145, the CPU 20
In step 146, c determines whether or not the defrost thermoswitch 24 is in the off state. In this case, since the temperature of the evaporator 14 is low immediately after the defrosting is started and the defrosting thermoswitch 24 is in the ON state, the step 146 is performed.
Is determined to be “NO”, and the circulation process including steps 143 to 146 is repeatedly executed until the temperature rises to such an extent that defrosting is completed and the defrosting thermoswitch 24 is turned off. During the circulation process, the display device 26 displays the fact that defrosting is being performed, as described above.

When the defrost thermoswitch 24 is turned off during the circulation process consisting of the steps 143 to 146, the CPU 20c determines "YES" in step 146, and energizes the coil X2 of the relay 19 in step 147. This is released, and the processing of this "defrosting routine" is ended in step 148. As a result, the normally open contacts X21, X22 of the relay 19 are turned off and the electromagnetic valve 18 is turned off, so that the supply of hot gas to the upstream of the evaporator 14 is stopped.

After the end of this "defrosting routine", the CPU2
0c returns the program to step 102 of FIG. 3, starts the operation of the first timer 20e for the next defrost in step 102, and operates and stops the cooling device by the circulation process including steps 103 to 106 described above. The alternate operation of is restarted and the operation as described above is continuously controlled.

Next, a case where an abnormality occurs in the thermostat will be described. First, a case where an abnormality occurs during the cooling operation of the thermostat will be described. Immediately after the electric compressor 11 starts up, a mechanical abnormality occurs in the electric compressor 11 itself such that the motor of the electric compressor 11 locks.
When the case temperature rises, the overload relay 17 shuts off the power supply path to stop the power supply to the electric compressor 11. In this case, since the overload relay 17 reacts immediately after the electric current flows into the electric compressor 11 (within at least 30 seconds after the start of activation), during the alternating operation of operating and stopping the cooling device, that is, step 103 to FIG. During the circulation processing of 106, step 112 of the "operation stop routine" of FIG.
The coil X1 of the relay 16 is energized, and the abnormality is detected in the "cooling operation routine" of FIG. 5 immediately after the second timer 20f is started in step 114. That is, "N" in step 121 of FIG.
After the determination "O", it is determined "YES" in step 122, that is, the overload relay 17 is off, and "NO" in step 127, that is, the second timer 2
0f is judged not to count up yet, and CP
The U20c outputs the display data representing "E1" to the display control circuit 25 in step 128, and stops energizing the relay X1 in step 130. As a result, the display control circuit 25 controls the display device 26 based on the display data, and the display device 26 displays “E” indicating an abnormality of the electric compressor 11.
The character "1" is displayed. Further, the operation of the cooling device is stopped by stopping the energization of the coil X1.

Further, after the electric compressor 11 is started, a rattling abnormality occurs in the condenser 12, the throttle 13, the evaporator 14 and their piping system, that is, the refrigerant piping system, and the electric compressor 11 When the case temperature abnormally increases, the overload relay 17 shuts off the power supply path to protect the compressor 11 and stops the supply to the electric compressor 11. In this case, even if the electric compressor 11 operates, the case temperature does not suddenly increase due to the increase in the refrigerant gas pressure. Therefore, during the alternate operation of operating and stopping the cooling device, that is, step 1 in FIG.
During the circulation process of 03 to 106, at least 30 seconds have passed since the coil X1 of the relay 16 was energized in step 112 of the "operation stop routine" of FIG. 4 and the second timer 20f was started in step 114. The abnormality is detected in the "cooling operation routine" of FIG. That is, after the determination of “NO” in step 121 of FIG. 5, it is determined in step 122 that “YES”, that is, the overload relay 17 is off, and step 1
In step 27, “YES”, that is, when it is determined that the second timer 20f is counting up, the CPU 20c outputs the display data representing “E2” to the display control circuit 25 in step 129, and the relay 16 in step 130. Stop energizing coil X1 of. As a result, the display control circuit 25
Controls the display 26 based on the display data, and the display 36 displays the letter "E2" indicating an abnormality in the refrigerant piping system. Further, the operation of the cooling device is stopped by stopping the energization of the coil X1.

On the other hand, during the defrosting operation of the cooling device,
When the electric compressor 11 itself has an abnormality, the CPU 20c
6 starts the operation of the second timer 20f in step 141 of FIG. 6 and immediately after energizing the coil X1 of the relay 16 in step 142 (within at least 30 seconds after starting the electric compressor), the abnormality of the electric compressor 11 occurs. Is detected. That is, in step 143, it is determined that the overload relay 17 is off, and in step 149, it is determined that “NO”, that is, the second timer 20f has not yet counted up, and the CPU 20c determines in step 15.
The display unit 26 is based on the display data indicating "E1" at 0.
The display 26 displays the character "E1" indicating the abnormality of the electric compressor 11. Further, the operation of the cooling device is stopped by stopping the energization of the coil X1.

When a malfunction occurs in the electromagnetic valve 18, the evaporator 14, and their piping system, that is, the piping system of the hot gas, or the defrosting thermoswitch 24 malfunctions, the gas pressure on the high pressure side is increased. Ascend and electric compressor 11
Case temperature rises abnormally, so the overload relay 17
Operates to stop the operation of the electric compressor 11. In this case, even if the electric compressor 11 operates, the case temperature does not suddenly rise, so during the defrosting operation of the cooling device, that is, steps 143 to 146 and 149 to 152 in FIG.
During the circulation process, the second timer 30f is started in step 141 before the circulation process, and at least 30 seconds after the coil X1 of the relay 16 is energized in step 142, the abnormality is detected. To be detected. That is, in step 143, "YES", that is, it is determined that the overload relay 17 is off, and in step 149, "YES", that is, it is determined that the second timer 20f is counting up, and the CPU 20c determines that the step 151. At step 152, display data representing "E3" is output to the display control circuit 25, and at step 152, the energization of the coil X1 of the relay 16 is stopped. As a result, the display control circuit 25
Controls the display unit 26 based on the display data, and the display unit 26 displays the character "E3" indicating an abnormality in the hot gas piping or a failure of the defrosting thermoswitch 24.
Further, the operation of the cooling device is stopped by stopping the energization of the coil X1.

As can be understood from the above description, according to the above embodiment, the overload relay 17 for detecting various abnormalities of the constant temperature machine is provided in the electric power supply path of the electric compressor 11, and various kinds of constant temperature machines are provided. The overload relay 17 is turned off in response to the abnormal increase in the case temperature of the compressor caused by the occurrence of the abnormality, and the power supply to the compressor 11 is cut off, and a signal indicating the occurrence of the abnormality is sent to the microcomputer 20. I am trying to output. Since the timing of occurrence of various abnormalities varies depending on the operating state of the cooling device as described above, the type of abnormality can be determined by considering the operating state, and the types are displayed as error codes E1 to E3. Therefore, even if an abnormality occurs in the thermostat, the user and the repairer can take appropriate measures. Therefore, the repair time of the thermostatic machine can be shortened, the repair cost can be reduced, and the operation stop time due to the occurrence of an abnormality can be shortened to improve the operating rate of the thermostatic machine.

In the above embodiment, the overload relay 17 is turned on / off by turning on / off a thermoswitch (not shown) provided in the case of the electric compressor 11.
Although the type that turns off is used, a type that turns off and shuts off the circuit when an excessive current flows due to the occurrence of an abnormality may be used.

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration of the invention described in the claims of the present invention.

FIG. 2 is an overall schematic block diagram of a thermostatic machine showing an embodiment of the present invention.

FIG. 3 is a flowchart of a program executed by the microcomputer of FIG. 2;

FIG. 4 is a detailed flowchart of the operation stop routine of FIG.

5 is a detailed flowchart of the cooling operation routine of FIG.

FIG. 6 is a detailed flowchart of the defrosting routine of FIG.

[Explanation of symbols]

11 ... electric compressor, 12 ... condenser, 13 ... throttle, 14 ...
Evaporator, 16, 19 ... Relay, 17 ... Overload relay, 1
8 ... Electromagnetic valve, 20 ... Microcomputer, 23 ...
Internal temperature sensor, 24 ... Defrosting thermoswitch, 26 ... Indicator.

Claims (2)

[Claims] 1. An electric compressor that rotatably drives according to electric power supply and circulates a compressed refrigerant through a condenser and an evaporator; and an electric compressor that is provided in a power supply path of the electric compressor and normally supplies electric power to the compressor. And a power cutoff means for cutting off the power supply to the compressor when the load on the compressor is excessive.
Inside temperature control means for detecting the temperature inside the refrigerator cooled by the evaporator, and by controlling the alternating operation of operating and stopping the electric compressor based on the temperature detected by the inside temperature detection means. In a thermostatic machine having an operation control means for maintaining the temperature between a predetermined upper limit temperature and a lower limit temperature, a time meter for measuring the time from the start of operation of the electric compressor.
When the measuring means and the power cut-off means cut off the power supply to the electric compressor , the time measuring means finishes measuring the predetermined time.
If there is a problem with the electric compressor,
And the time measuring means measures the predetermined time.
Cooling of the condenser, evaporator, etc. on condition that it has been completed
Abnormality type judgment to judge that an abnormality has occurred in the piping system of the medium
A constant section, the abnormality type determining more determined to be the electric compressor means
And an abnormality display device for displaying the abnormality and the abnormality of the refrigerant piping system separately . 2. An electric compressor that circulates a compressed refrigerant that is rotatably driven according to electric power supply through a condenser and an evaporator, and a hot gas is selected from a downstream of the electric compressor to an upstream of the evaporator. Power supply to the electric compressor, which is provided in the electric power supply path of the electric compressor and supplies electric power to the compressor, and cuts off the electric power supply to the compressor when the load of the compressor is excessive. Means, and an in-compartment temperature detecting means for detecting a temperature in the interior cooled by the evaporator,
An evaporator temperature detecting means for detecting the temperature of the evaporator, and an upper limit of the inside temperature which is predetermined by controlling the alternating operation of the operation and stop of the electric compressor based on the temperature detected by the inside temperature detecting means. Driving control maintained between temperature and lower limit temperature
Control means and the operation and operation of the electric compressor by the operation control means.
When the electric compressor is operated during alternate operation of
Turn on the electromagnetic valve and detect the evaporator temperature.
When the temperature detected by the stage rises to a predetermined temperature
While turning off the solenoid valve and turning on the solenoid valve
In a thermostat equipped with a defrost control means for defrosting the evaporator, the time from the defrost start by the defrost control means is measured.
When the time measuring means and the electric power cutoff means cut off the electric power supply to the electric compressor , the time measuring means ends the measurement of a predetermined time.
If there is a problem with the electric compressor,
And the time measuring means measures the predetermined time.
The electromagnetic valve, evaporator, etc. provided that it has been completed.
There is something wrong with the hot gas piping system or the evaporator temperature detection means.
And abnormal kind determination means for determining that it has occurred, the abnormality type determining more determined to be the electric compressor means
Abnormality and the hot gas piping system or evaporator temperature detection
An abnormality display device for a thermostatic machine, comprising: a display means for distinguishing and displaying a step abnormality .