JPH02247456A - Protection device for refrigerator - Google Patents

Abstract

PURPOSE:To prevent a rise in a temperature inside a refrigerator and cooling operation therein from becoming impossible by installing a gas restricting valve which restricts hot gas leaking in a bypass pipe during an operational failure of a hot gas control valve to said bypass pipe which connects the hot gas control valve with a vaporizer. CONSTITUTION:A relay for a gas restricting valve 15 is OFF-controlled during a full opening command of a hot gas control valve 2 so that both an in-flow port 15a and an out-flow port 15b for the gas restricting valve 15 may be connected wit each other, thereby communicating a bypass passage 10. It is ON- controlled during a full closing command of the hot gas control valve 2 so that the in-flow port 15a may be connected with a change over port 15c. Therefore, when a foreign matter gathers in upon the hot gas control valve 2 during cooling operation inside a refrigerator or adheres to the valve under a full opening state, the in-flow port 15a is connected with the change over port 15c so that hot gas which has leaked out in the bypass passage 10, flows from the change over port c into the downstream side of the hot gas control valve 2 in the refrigerant piping 6 and then into a vaporizer 3, thereby maintaining cooling operation.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a protection device for a refrigeration device, and more particularly to a protection device for a refrigeration device capable of cooling the internal temperature to a chilled region higher than -5°C to -6°C. .゛(Prior art) Conventionally, this type of refrigeration equipment has been developed, for example, in
As disclosed in Publication No. 50351, a proportional control type hot gas is installed in the gas refrigerant piping connecting the compressor and the condenser to bypass a portion of the hot gas flowing from the compressor to the condenser and to flow it to the evaporator. A device is known that is equipped with a gas control valve and adjusts the refrigerating capacity by controlling the bypass amount of the hot gas to achieve cooling to a chilled region. In addition, the above-mentioned hot gas control valve is configured with a three-way valve that opens and closes (ON-0/FF type), and turns OFF during cooling operation inside the refrigerator, allowing the entire amount of hot gas to flow to the condenser and defrosting the evaporator. It is known that the evaporator is turned on during operation to allow the entire amount of hot gas to flow directly into the evaporator, thereby performing a defrost operation of the evaporator.

(Problems to be Solved by the Invention) In the above-mentioned refrigeration system, when a proportional control type hot gas control valve is commanded to fully open or when an open/close type hot gas control valve is commanded to close (at the end of defrost operation), If a foreign object gets caught inside the valve, the entire amount of hot gas should normally flow to the condenser, but some of it leaks into the evaporator from the gap in the hot gas control valve where the foreign object gets caught. The temperature inside the refrigerator increases. On the other hand, if the hot gas control valve is stuck in the fully open state, the entire amount will flow to the evaporator, making cooling operation inside the refrigerator impossible. For this reason, it is desirable to take measures in advance to deal with abnormalities in the hot gas control valve.

The present invention has been made in view of the above, and its purpose is to restrict hot gas leaking from the hot gas control valve from flowing to the evaporator in the event of an abnormality in the hot gas control valve. Therefore, even in this abnormal situation, the temperature inside the refrigerator is prevented from rising and the cooling operation inside the refrigerator becomes impossible, and the cooling operation inside the refrigerator is maintained in a good condition.

(Means for Solving the Problem) In order to achieve the above object, the invention according to claim (1) of the present application has a compressor (1) and a condenser (3) as shown in FIG. The target is a refrigeration system in which a hot gas control valve (2) for flowing hot gas discharged from the compressor (1) to an evaporator (5) is arranged in a gas refrigerant pipe (6) that connects the compressor (1) to the evaporator (5). Then, the hot gas control valve (2) and the evaporator (
5) Bypass piping (10) that connects and flows hot gas
Further, a gas restriction valve (15) is arranged to restrict hot gas leaking into the bypass pipe (10) from flowing to the evaporator (5) when the hot gas control valve (2) is abnormal.

Further, in the invention according to claim (3), the gas restriction valve (15
) is arranged in a refrigerant pipe (6) that connects the compressor (1) and the hot gas control valve (2).

Therefore, if a defrost operation of the evaporator using hot gas is required when restricting the flow of hot gas to the evaporator due to an abnormality in the hot gas control valve as described above, Due to the restriction of circulation, defrosting operation of the evaporator cannot be performed. Therefore, claim (4)
In the invention according to the above, when a defrost operation of the evaporator Z+ (5) is commanded, a refrigeration system of a predetermined type is used so that the hot gas restricted by the gas restriction valve (15) can flow back to the evaporator (5). That is, as shown in FIG. 11, the hot gas flowing through the bypass pipe (10) is first passed through the evaporator (
5) After flowing into the drain pan heater (13), the evaporator (
5) By using a refrigeration system pre-installed with a three-way valve (20R4) for switching the distribution route, the bypass piping (10) on the downstream side of the three-way valve (20R4) for the drain pan heater is installed.
The gas restriction valve (60) as described above is disposed in the fuel cell.

(Function) With the above configuration, in the invention according to claim (1), in the event of an abnormality such as when a foreign object is caught in the proportional control type or opening/closing type hot gas control valve (2), the control valve (2) can be used when a fully closed command is issued. Also, some of the hot gas flows into the bypass pipe (1) from the gap between foreign objects.
0). However, that hot gas is removed by the gas restriction valve (
15) restricts the flow to the evaporator (5), so the situation is substantially the same as when the hot gas control valve (2) is normal, and cooling operation within the refrigerator is ensured.

Further, in the invention according to claim (3), the hot gas discharged from the hot gas (1) is prevented from flowing into the hot gas control valve (2) itself by the gas restriction valve (15).

In this case, if a three-way valve is used to flow the hot gas discharged from the compressor (1) to the condenser (3), cooling operation within the refrigerator can be ensured.

Further, in the invention according to claim (4), the hot gas leaking from the hot gas control valve (2) to the bypass pipe (10) flows down the bypass pipe (10) via the three-way valve (20R4), but the hot gas The restriction valve (60) closes the evaporator (5) as described above.
). On the other hand, if defrost operation of the evaporator (5) is requested in this state, the three-way valve (20R4) is closed. As a result, the hot gas leaking into the bypass pipe (10) is removed from the three-way valve (20R4).
After flowing into the drain pan heater (13) and warming it, it flows to the evaporator (5), so that the defrost operation of the evaporator (5) is ensured.

In the above case, the gas restriction valve (15).

When (60) is configured with a three-way valve, the intense hot gas can be actively returned to the upstream side of the condenser (3), even if the hot gas control valve (2) is stuck in the fully open state. It is possible to ensure cooling operation inside the building. Furthermore, in the event of an abnormality due to foreign matter being caught, the amount of hot gas leaking is small, so even if this leaked hot gas is returned to the downstream side of the condenser (3), a good cooling operation can be continued. In addition, a gas restriction valve (15), (
If 60) is configured with a two-way valve and a throttle mechanism connected in parallel to the two-way valve, the amount of hot gas leaking to the evaporator (5) can be effectively restricted.

(Effects of the Invention) As explained above, according to the present invention, in a refrigeration system equipped with a proportional control type or opening/closing type hot gas control valve, even when an abnormality occurs in the hot gas control valve, the hot gas control The gas restriction valve restricts the flow of hot gas leaking from the valve to the evaporator, which prevents the temperature inside the refrigerator from rising and the refrigerator's cooling operation becoming impossible, and maintains the refrigerator's internal cooling operation. can.

In particular, if the gas restriction valve is placed downstream of a three-way solenoid valve for a drain pan heater that is provided in advance in the refrigeration system, this can be done when commanding defrost of the evaporator.

In addition, if the gas restriction valve is configured as a three-way valve, the hot gas discharged from the compressor can flow directly to the condenser without flowing to the hot gas control valve, or the hot gas leaking from the hot gas control valve can be passed upstream of the condenser. It can be returned to the side or downstream side, ensuring cooling operation inside the warehouse. Also, if the gas restriction valve is configured with a two-way valve and a throttle mechanism, the steam 5I! The amount of hot gas flowing into the vessel can be effectively restricted.

Further, if the gas restriction valve is automatically controlled, reliability of operation can be ensured, and if it is manually controlled, the device can be manufactured into a commercial product.

(Example) Embodiments of the present invention will be described below with reference to the drawings.

In Figure 1, (A) is a refrigeration system installed in a refrigerated container, etc., (1) is a compressor with an unloading mechanism that can change the capacity to 33%, 67%, and 100%, and (3) is an air cooling fan ( Condensing W with attached Fl) and motor (MFl)
, (18) is a receiver, (4) is a PID-controlled electronic expansion valve, (5) is an internal fan (F2) and a motor (MF
2) is attached to the evaporator S, (19) is an accumulator, and each device (1), (3), (18).

(4), (5), and (19) are the refrigerant pipes (
The refrigerant circulation circuit (11) is connected in series with the refrigerant circulation circuit (11).
), and by circulating the refrigerant circulation circuit (11) using the compressor (1) in the cooling region, the heat of the refrigerant gas is released to the outside of the refrigerator in the condenser (3), and the refrigerant is It is configured to liquefy the gas and vaporize the refrigerant gas in the evaporator (5), thereby absorbing the heat inside the refrigerator and thereby cooling the inside of the refrigerator.

Further, (2) is a hot gas control valve installed in a gas refrigerant pipe (6) connecting the compressor (1) and the condenser (3), and the hot gas control valve (2) is , an inflow port (2a), an outflow port (2b), and a bypass port (
The bypass port (2C) bypasses the condenser (3), the receiver (18) and the electronic expansion valve (4) via the bypass piping (10) to prevent evaporation. Refrigerant pipe (12) on the suction side of the device (5)
It is connected to the. Therefore, the hot gas control valve (2)
When fully closed, the bypass port (2C) is closed and the inflow port (2a) is connected to the outflow port (2b), while when it is open, the inflow port (2a) is connected to the bypass port (2C).
2C), and the larger the opening degree of the connection, the more hot gas discharged from the compressor (1) will be bypassed from the bypass pipe (10) to the evaporator (5). It is configured to flow.

Next, the specific configuration of the hot gas 1lal valve (2) is shown in Fig. m2. In the hot gas control valve (2) shown in the figure, an inflow port (2a) is provided inside the valve body on the right side of the figure, an outflow port (2b) is provided at the upper left side of the figure, and a bypass port is provided at the bottom. (2c) is provided. Also,
A spool (2d) is slidably disposed in a portion where the three ports (2a) to (2c) communicate with each other, and the spool (2d)
2d) moves downward in the figure as the current value that passes through the proportional solenoid (not shown) increases. ), a lower part (2r) is disposed near the communicating portion between the inflow port (2a) and the bypass port (2c).

By controlling the current value that passes through the proportional solenoid, the rise (2o) and lower part (2r) of the spool (2d) are controlled.
) and the communication area between the inflow port (2a) and the outflow port (2b) and the inflow port (2a) and the bypass port (2c).
) and the bypass port (2C
) functions to adjust the amount of hot gas bypassed to the

If the spool (2d) is stuck in the open state,
As shown in FIG. 3, when the lower part (2r) catches a foreign object (F), hot gas leaks from the gap to the bypass port (2C).

In addition, in FIG. 1, the drain pan heater pipe (13) of the evaporator (5) is connected in parallel to the bypass pipe (10), and the upstream parallel section of the drain pan heater pipe (13) is connected in parallel to the drain pan heater pipe (13) of the evaporator (5). A three-way valve (20R4) consisting of a three-way solenoid valve for the drain pan heater piping is installed. A gas restriction valve (15) is arranged in the bypass passage (10) upstream of the three-way solenoid valve (20R4). The gas restriction valve (15) is composed of a three-way solenoid valve, and an inflow port (15a) and an outflow port (15b) are connected to its bypass passage (10), and the remaining switching port (15c) is connected to a pipe (16). The above compressor (1
) and the condenser (3) on the downstream side of the hot gas control valve (2) of the gas refrigerant pipe (6). Therefore, the gas restriction valve (15) has both inflow and outflow ports (
15a).

(15b) to communicate with the bypass passage (10), connect the inflow port (15a) to the switching port (15c), and connect the outflow port (15b) to the switching port (15c).
) is turned on to close.

In addition, in FIG. 1, (Thl) and (Th2) are refrigerant temperature sensors that detect the inlet refrigerant temperature and outlet refrigerant temperature of the evaporator (5), and (Th3) and (Th4) are refrigerant temperature sensors that detect the inlet refrigerant temperature and outlet refrigerant temperature of the evaporator (5). 5) is an air temperature sensor that detects the intake air temperature and the outlet air temperature (temperature inside the refrigerator). And each of the temperature sensors (Thl), (Th2), (Th3),
As shown in FIG. 4, the detection signal of (Th4) is configured to be input to a controller (21), and the controller (21) includes an A/D converter (23),
I10 port (24), RAM (25), ROM
(26) and a CPU (27). The controller (21) is equipped with an opening detection means (8) for detecting the opening of the electronic expansion valve (4), and
During refrigeration operation, each refrigerant temperature sensor (Thl), (T
Based on the detection signal of h2), PID the electronic expansion valve (4) (7)%-verter (MEV) so that it reaches a predetermined degree of superheating.
On the other hand, during refrigeration operation, the temperature of the discharged air is controlled to be within a predetermined temperature range (within ±5°C of the set temperature) based on the detection signal of the discharged air temperature sensor (Th4) of the evaporator (5). includes an expansion valve control means (14) that performs PID control on the motor (MEV) of the electronic expansion valve (4). The controller (21) also controls the hot gas bypass amount by PID controlling the electronic expansion valve (4) and the motor (MV) of the hot gas control valve (2) during refrigeration operation. The motor (MV) controls the air temperature within a predetermined temperature range (within ±0.5°C of the set temperature) and fully opens the hot gas control valve (2) during defrost operation of the evaporator (5). Hot gas control means (17) are included for controlling the hot gas control means (17).

Furthermore, the controller (21) is equipped with a compressor capacity control means (7) for controlling the capacity of the compressor (1) to increase in response to an increase in heat load.

Furthermore, in FIG. 4, (Tr) is a transformer, (S)
is the run/stop switch, (31) is the high pressure switch, (
32) is a low pressure switch, (33) is a hydraulic protection pressure switch, (34) is a lamp switch, (35) is a hydraulic reset switch, (36) is a compressor protection thermoswitch, (
37) is a manual switching switch for switching the connection of the transformer (Tr), (38) is for voltage switching, and (39) and (40) are manual switching switches for the compressor motor. ~(40
) are all linked.

In addition, (MC) is a compressor motor, and (10c) is a condenser (3) that simultaneously operates the compressor motor (MC).
compressor relay (IOF) with a normally open contact (IOC-1) that allows energization of the blower fan motor (MFI
) is an evaporator fan relay with a normally open contact (IOF-1) that operates the blower fan motor (MF2) of the evaporator (5).

Further, (2OR?) is a relay for the gas restriction valve (15), and this relay (20R7) is used when the hot gas control valve (2) is commanded to fully open (in other words, the hot gas to the bypass passage (10) is When the gas limit valve (15
) both inflow and outflow ports (15a), (15b
) to communicate the bypass passage (10),
When the hot gas control valve (2) is commanded to fully close (that is, when the bypass amount of hot gas to the bypass passage (10) is commanded to be zero)
In this case, the inflow port (15a) of the gas restriction valve (15) is connected to the switching port (15c) by being controlled to be ON.

Therefore, in the above embodiment, when a foreign object gets caught in the hot gas RArIJ valve (2) during cooling operation inside the refrigerator, or in an abnormal situation where the hot gas RArIJ valve (2) is stuck in the fully open state, the gas restriction valve (15) is turned ON. controlled, its inlet port (15
a) communicates with the switching port (15c). As a result, the hot gas leaking into the bypass passage (10) flows to the gas restriction valve (15), and then flows to the switching port (15c).
) flows to the downstream side of the hot gas control valve (2) of the gas refrigerant pipe (6) and flows into the condenser (3), thereby substantially ensuring cooling operation within the refrigerator.

FIG. 16 shows an embodiment in which the hot gas control valve (2) is modified and the arrangement position of the gas restriction valve (15) is changed. In the above embodiment, the hot gas control valve (2) is of a proportional control type. Instead of configuring with , it is configured with an open/close type (2"), and during cooling operation inside the warehouse, the inflow port (2al and outflow port (2b) are connected and the bypass port =) (2c
-), while when defrosting operation of the evaporator (5) is required, the inlet port (2a '') is set to the bypass port).
(2cm) and closes the outflow port (2b-). Further, instead of disposing the gas restriction valve (15) in the bypass passage (10), the gas restriction valve (15) is arranged in the bypass passage (10).
') is installed in the refrigerant pipe (6) between the compressor (1) and the hot gas control valve (2), and its inlet port (15a-) and outlet port (15b=) are connected to the Connect to the refrigerant pipe (6), and connect the switching port (156-) to the refrigerant pipe (6) on the downstream side of the hot gas control valve (2'), so that when the hot gas control valve (2') is abnormal, the inflow port (15a
-) is connected to the switching port (15 cm).

Therefore, in this embodiment, the hot gas control valve (
2'), the hot gas discharged from the compressor (1) will not flow to the hot gas control valve (2') and will flow from the switching port (150'') of the gas restriction valve (15->) to the condenser (
3), so good cooling operation inside the refrigerator can be ensured.

In addition, Figure 5 shows the above gas restriction valve (three-way solenoid valve) (15).
An electric circuit diagram of an embodiment in which the is manually controlled by switch operation is shown. In other words, in the same figure, there are two sets of 0N1 operated by the operator.
A 0FF switch (50) is placed, and this 0N10FF
By closing the switch (50), the relay (20R7) for the gas control valve (15) is controlled to ON, and the gas control valve (15) is turned ON.
5) is switched to connect the inlet port (15a) to the switching bow (15c). In addition, the above two series of 0N10
The other two normally closed contacts of the P[' switch (50) are each
It is interposed between the signal input circuit of the thermistor (T11) for detecting young frost of the evaporator (5) and the command circuit of the manual defrost command switch (3D), and automatic defrost is activated by operating the 0N10FF switch (50). Driving and manual defrost operation are prohibited.

Furthermore, Figure 6 shows the above gas control valve (three-way solenoid valve) (15).
An example is shown in which the is configured with a manual three-way closing valve (51),
During the closing operation, the inflow port (51a) is switched
1b).

In addition, in FIG. 7, the gas restriction valve (15) is composed of a three-way solenoid valve (52) and a throttling mechanism (53) made of a capillary tube connected in parallel to the three-way solenoid valve (52). In this case, the electric circuits when the three-way solenoid valve (52) is automatically controlled by the controller (21) or manually controlled by the 0N10FF switch are the same as those shown in FIGS. 4 and 5 above, and will therefore be omitted. Furthermore, the three-way solenoid valve (52) may be constructed as a three-way closing valve (54) as shown in FIG. In this case, as shown in the electric circuit of Fig. 9, a three-way closing valve (
An interlocking switch (9) that turns ON in conjunction with the closing of (54)
0), and the opening operation of the normally closed two contacts of the interlocking switch (90) connects the signal input circuit of the thermistor (Th) for frost detection of the evaporator (5) and the manual defrost command switch (3D). The defrost operation is prohibited regardless of whether it is automatic or manual.

Therefore, in this embodiment, the bypass pipe (10) is closed by the closing operation of the three-way solenoid valve (52) or the three-way closing valve (54), and most of the leaked hot gas is absorbed by the throttling mechanism (54).
3), the flow is restricted and only a very small amount flows from the throttling mechanism (53) to the evaporator (5), so the rise in temperature inside the refrigerator is effectively suppressed, and the bypass piping (1, 0
) is prevented from abnormally increasing refrigerant pressure.

Moreover, FIG. 10 shows an embodiment in which the connection point of the switching port (15c) of the gas restriction valve (15) in FIG. 1 is changed,
In the above embodiment, the gas refrigerant pipe (6) is connected to the hot gas control valve (2) downstream, whereas the condenser (3) is connected downstream to the receiver (18) upstream to the refrigerant pipe (57). The leaked hot gas is stored in the receiver (18). Therefore, in this embodiment, although the refrigerating capacity is reduced due to the fact that the leaked hot gas does not flow to the condenser (3), it can be sufficiently coped with when the amount of leaked hot gas is small.

Furthermore, FIG. 11 shows an embodiment of the invention according to claim (4), and FIG. 1 shows a gas restriction valve (
15) is placed upstream of the drain pan heater piping three-way solenoid valve (20R4) in the bypass passage (10),
arranging a gas restriction valve (60) in the bypass piping (10) in the parallel section of the drain pan heater piping (13);
Relay (20R7) for gas restriction valve (15) in Figure 2 above
Similarly, when the hot gas control valve (2) is outputted with a fully open command signal, it is turned on and automatically controlled to connect the inflow port (60a) of the gas restriction valve (60) to the switching port (60c). .

In addition, the three-way solenoid valve (2) for the drain pan heater piping (13)
0R4) is always in the OFF state and the bypass passage (
10), while at the time of ON operation, the three sides f1
The bypass passage (10) on the upstream side of the 1ra valve (20R4) is connected to the drain pan heater piping (13) side, and the hot gas is passed through the drain pan heater piping (13) to the evaporator (5).
It has the function of flowing to

Therefore, in this embodiment, during the cooling operation in the refrigerator, the drain pan heater piping three-way solenoid valve (20R4) is turned off and communicates with the bypass passage 10.

Therefore, when the hot gas control valve (2) is commanded to fully close, the gas restriction valve (60) is controlled to be ON by the controller (21), and the inflow port (60a) is switched to the switching port (60c).
). This allows the hot gas control valve (
Although some hot gas leaks into the bypass passage (10) when foreign matter gets caught in step 2), this leaked hot gas flows through the three-way solenoid valve (20R4) for the drain pan heater piping.
After flowing through the gas restriction valve (60), the gas flows from the switching port (60c) through the piping (16) to the condenser (3), thereby effectively ensuring good cooling operation within the refrigerator.

Moreover, when defrost operation of the evaporator (5) is requested in the above condition, the three-way solenoid valve (20R4) for the drain pan heater piping is turned on, and the entire amount of leaked hot gas is transferred to the drain pan heater piping (13). ) to the evaporator (5)
Therefore, the defrost operation of the evaporator (5) can be ensured.

In addition, Fig. 12 shows the gas restriction valve (three-way solenoid valve) (60
) is manually controlled by the 0N10FF' switch, and the relay (20R7) for the gas control valve (60) is turned ON by closing the 0N10r'P switch (61) operated by the operator. The inflow port (60a) of the gas control valve (60) is switched to be connected to the switching port (60C). Furthermore, Fig. 13 shows an embodiment in which the gas control valve (three-way solenoid valve) (60) is configured with a manual three-way closing valve (61), and when the valve is opened, the inflow port (61a) is connected to the outflow port (61b). At the same time, during the closing operation, the inflow bow (61a) is switched and connected to the switching port (61c).

In addition, FIG. 14 shows a configuration in which the gas restriction valve (three-way solenoid valve) (60) shown in FIG. be. The electric circuit for automatically controlling the three-way solenoid valve (63) is the same as shown in Figure 4 above, and is 0N10.
The electric circuit for manual control using the FF switch is the same as that shown in FIG. 12, so its explanation will be omitted. Further, FIG. 15 shows an arrangement in which a three-way closing valve (65) is used in place of the three-way solenoid valve (63).

[Brief explanation of drawings]

The drawings show an embodiment of the present invention. Fig. 1 is a refrigerant piping system diagram showing the overall configuration, Fig. 2 is a sectional view showing the internal structure of the hot gas control valve, and Fig. FIG. 4, which is an explanatory diagram of the closed state, is an electric circuit diagram. Also, Figure 5 is an electric circuit diagram when the gas restriction valve is manually controlled, Figure 6 is a main piping system diagram when the gas restriction valve is configured as a three-way closing valve, and Figure 7 is a diagram of the main part piping system when the gas restriction valve is configured as a three-way closing valve. Figure 8 is a diagram of the main piping system when the gas restriction valve is configured with a three-way closing valve and throttle mechanism. Main part electric circuit diagram when a three-way closing valve forms part of a gas restriction valve, No. 10
The figure is a main part piping system diagram showing another embodiment of the return point for the leaked hot gas. Furthermore, Fig. 11 is a refrigerant piping system diagram showing an example in which a gas restriction valve is disposed in the bypass passage downstream of the solenoid valve for drain pan heater piping, and Fig. 12 is an electrical diagram showing an example in which the gas restriction valve shown in Fig. 11 is manually controlled. The circuit diagram, Fig. 13 is a main piping system diagram showing an example in which the gas restriction valve shown in Fig. 11 is configured with a three-way closing valve, and Fig. 14 is a circuit diagram showing an example in which the gas restriction valve shown in Fig. 11 is configured with a three-way solenoid valve and a throttle mechanism. Fig. 15 is a piping system diagram of the main parts when the gas restriction valve is configured with a three-way closing valve and a throttling mechanism, and Fig. 16 is another example of the configuration of the hot gas control valve. and FIG. 7 is a diagram showing another example of the arrangement position of the gas restriction valve. (1)... Compressor, (2), (2-)... Hot gas control valve, (3)... Condenser, (5)... Evaporator,
(6)...Gas refrigerant piping, (10)...Bypass passage, (15), (15-), (60)...Gas restriction valve, (15a)...Inflow port, (15b) ...Outflow port, (15e)...Switching port, (13)...
・Drain pan heater, (20R4)...Three-way valve for drain pan heater piping, (20R7)...Relay for gas restriction valve (50), (61)...0N10FF switch', (51)...Three-way closure Valve, (52), (63
)...Two-way valve, (53), (64)... Throttle mechanism, (54), (65)... Three-way closing valve. zuLπ-5 (1)... Compressor (2)... Hot gas control valve (3), Condenser (5)... Evaporator (6), Gas refrigerant piping (10)... Bypass passage (15), (60)...Gas restriction valve (158)...
・Inflow port (15b)...Outflow port (15c)...Switching port (13)...Drain pan heater (20R4)...Drain pan hill Yuzuki three-way valve (20R
7)...Gas limit valve relay (50), (61)...0N10FF switch (5)
1)... Three-way closing valve (52), (63)... Two-way valve (53), (64)... Throttle mechanism (54),
(65)...Two-way closing valve Fig. 10

Claims (10)

[Claims] (1) A hot gas disposed in the gas refrigerant pipe (6) connecting the compressor (1) and the condenser (3) to flow the hot gas discharged from the compressor (1) to the evaporator (5). In a refrigeration system equipped with a control valve (2), the hot gas control valve (2) is connected to a bypass pipe (10) that connects the hot gas control valve (2) and the evaporator (5) and allows hot gas to flow therethrough.
a gas restriction valve (15) that restricts hot gas leaking into the bypass pipe (10) from flowing to the evaporator (5) in the event of an abnormality;
) is arranged. (2) A hot gas disposed in the gas refrigerant pipe (6) connecting the compressor (1) and the condenser (3) to flow the hot gas discharged from the compressor (1) to the evaporator (5). In a refrigeration system equipped with a control valve (2), the hot gas control valve (2) is connected to a bypass pipe (10) that connects the hot gas control valve (2) and the evaporator (5) and allows hot gas to flow therethrough.
a gas restriction valve () that restricts hot gas leaking into the bypass pipe (10) from flowing into the evaporator (5) when a fully closed command is issued;
15) A protection device for a refrigeration device, characterized in that: (3) A hot gas disposed in the gas refrigerant pipe (6) connecting the compressor (1) and the condenser (3) to flow the hot gas discharged from the compressor (1) to the evaporator (5). In a refrigeration system equipped with a control valve (2), the compressor (1)
Refrigerant piping (6) connecting the and hot gas control valve (2)
A gas restriction valve (15') is disposed in the hot gas control valve (15') for restricting hot gas flowing into the refrigerant pipe (6) from flowing to the evaporator (5) when the hot gas control valve (2) is abnormal. Protection device for refrigeration equipment. (4) A hot gas disposed in the gas refrigerant pipe (6) connecting the compressor (1) and the condenser (3) to flow the hot gas discharged from the compressor (1) to the evaporator (5). A control valve (2) is provided, and the hot gas control valve (2) is provided with the hot gas control valve (2).
The hot gas flowing into the bypass pipe (10) is connected to the evaporator (5) and passed through the drain pan heater (13) of the evaporator (5) to the bypass pipe (10) through which the hot gas flows. ) In a refrigeration system equipped with a three-way valve (20R4) that allows flow to the hot gas control valve (20), a valve (20R4) is provided downstream of the three-way valve (20R4) of the bypass piping (10), and when there is an abnormality in the hot gas control valve (2), the bypass piping (10) is Gas restriction valve (60) restricting the flow of escaping hot gas to the evaporator (5)
A protection device for a refrigeration device, characterized in that: (5) The hot gas control valve (2) is a proportional control type that allows a portion of the hot gas discharged from the compressor (1) to flow into the evaporator (5) in larger amounts as the opening degree increases, or Claims (1), (2), (3) or (4) A protection device for a refrigeration device as described above. (6) Claims (1), (2), (3), (4) wherein the gas restriction valve (15, 15', 60) is a three-way valve.
Or the protection device for the refrigeration equipment described in (5). (7) The gas restriction valve (15, 60) is connected to the switching port (1
5c, 60c) is connected to the gas refrigerant pipe (6) on the downstream side of the hot gas control valve (2) or on the downstream side of the condenser (3). , (5) or (
6) The protection device for the refrigeration equipment described above. (8) The gas restriction valve (15') is composed of a three-way valve,
And the switching port (15c') is the hot gas control valve (2).
The protection device for a refrigeration system according to claim 3 or 5, wherein the protection device is connected to a refrigerant pipe (6) between the and the condenser (3). (9) The gas restriction valve (15, 60) is a two-way valve (52,
63) and a throttle mechanism (53, 64) connected in parallel to the two-way valve (52, 63),
(2), (4) or (5) protection device for a refrigeration equipment. (10) The gas restriction valves (15, 15', 60) are operated by the controller (21) when the hot gas control valve (2) is fully closed.
) Claims (1), (2), (3), (4), (5) whose operation is automatically controlled or manually controlled by
, (6), (7), (8) or (9).