JPH0268458A - Freezer - Google Patents

Abstract

PURPOSE:To reduce a starting load of a compressor by a method wherein a balancing valve and a controller device for operating the balancing valve are provided, pressures at a discharging side and an intake side of the compressor are kept at their balanced state when the compressor starts to operate. CONSTITUTION:When a temperature within a freezing box reaches a predetermined value, a controller device 2 may stop an energization of a refrigerant valve 12 and at the same time an electromagnetic clutch 81 is turned off and a compressor 91 is stopped. At this time, a balancing valve 11 is energized by the controller device 2, passages of the nozzles A and C are opened and a space between the A and B is closed, gas coolant discharged from the compressor 91 enters directly an evaporator 95 without passing a condensor 92 and a metering device 94. That is, a discharging side 912 and an intake side 911 of the compressor 91 communicate to each other. Since a releasing of the nozzles A and C is carried out for several seconds to several ten seconds, the discharging side 912 and the intake side 911 are balanced at their pressures. After the space between the nozzles A and C is closed, the space between the nozzles A and B is opened again and the apparatus is ready for a subsequent starting of the compressor. In this way, the load at the beginning of operation can be substantially reduced.

Description

[Detailed description of the invention] [Industrial application field] Ru.

[Prior art]

Conventionally, the basic configuration of a refrigerator includes a compressor 91. Condenser92. Squeezing device 94. It consists of an evaporator 95. In this cooling system, the throttle device 9
4, the refrigerant that has been adiabatically expanded and cooled is sent to the evaporator 95, and the fan 951 sends cold air from the evaporator 95 to the freezer to freeze it. In the cooling system described in item 1, 93 is a receiver, 96 is an accumulator, and 921 is a condenser fan. Furthermore, the compressor 91 is connected to a drive source such as an engine 85 of an automobile via an electromagnetic clutch 81 , a pulley 82 , a V heald 83 , and a pulley 84 .

Further, although the above example shows that the compressor 91 is connected to the engine 85 via the electromagnetic clutch 81, the compressor 81
may be directly connected to a drive source such as an engine or an electric motor.

In this way, the compressor is driven directly by the engine or electric motor, or via an electromagnetic clutch or the like as shown in FIG. 3 above.

(Problem to be solved) However, when starting a compressor, in addition to the rotational load of the compressor itself, the starting torque of the compressor is affected by the inertia of various parts such as the engine, electric mower, electromagnetic clutch, pulley, heald, etc. becomes large.

Therefore, in the case of a direct drive method using an engine or an electric motor, engine startability deteriorates and electric morph inrush current increases. Further, even in the case of a transmission method using an electromagnetic flanch or the like, there is a risk that excessive force is applied to various parts such as the clutch, causing damage to these devices.

As described above, conventional refrigerators have poor startability and problems with the durability of related equipment.

However, the time when the compressor starts is the cooling cycle (
cooling operation). The start of this operation is when the temperature inside the freezer reaches a predetermined temperature while the cooling system is in operation, the compressor temporarily stops, and then the temperature rises and the compressor starts operating again. There is also a point in time when the cooling system is activated, for example when the vehicle starts driving.

In view of these problems, the present invention aims to provide a refrigerator with excellent startability and durability.

[Means for solving problems]

The present invention connects a compressor, a condenser, a throttle device, and an evaporator, and also provides a refrigerant valve between the condenser and the throttle device, and a check valve on the discharge side of the compressor. a cooling system configured to circulate refrigerant between the two; a balance valve that balances the pressure between the discharge side and the suction side of the compressor for a predetermined period of time when the compressor is stopped or started; and a control device that opens and closes the balance valve.

What should be noted in the present invention is that the balance valve and the control device that operates the balance valve are installed so that the pressures on the discharge side and suction side of the compressor are balanced (
This is because the load on the compressor at start-up is reduced by ensuring that the compressor is in an equilibrium state.

Therefore, as the above-mentioned balance valve, Embodiment 1
As shown in Section 1), a three-way valve is provided on the discharge side of the compressor, and the refrigerant is switched so that it flows in the direction of the condenser during the cooling cycle, and on the other hand, so that the refrigerant flows directly into the generator during the above-mentioned pressure suspension. There is. This three-way valve switching means can also be used when defrosting (or warming) a freezer (see the first embodiment).

In addition, as another means for the 5 balance valve, as shown in the second embodiment, an on-off valve such as a solenoid valve is provided between the discharge side and the suction side of the compressor, and the on-off valve is closed during the cooling cycle. On the other hand, there is also a means to open the refrigerant and bypass the compressed refrigerant directly to the suction side of the compressor during the pressure halrance.

Therefore, the timing to open the balance valve, that is, the timing to balance the pressure between the discharge side and the suction side of the compressor, is as follows:
As mentioned above, there is a time when the inside of the freezer is cooled to the set temperature and the compressor is stopped. Alternatively, this may occur after the refrigerator itself has been stopped. Further, this pressure balance timing can also be performed before starting the refrigerator. In the first two cases, the balance valve is opened for several seconds to several tens of seconds after the compressor stops operating. In the latter case, the balance valve is first opened for several seconds to several tens of seconds when the refrigerator is started, and after the refrigerator is stopped, the compressor is operated.

The opening and closing operations of the balance valve as described above are performed by the control device in conjunction with the operation of the compressor. That is, for example, the control device inputs a stop signal for the compressor 1, opens the balance valve for the predetermined period of time based on this signal, and then stops the compressor. Alternatively, the control device generates a starting start signal 3 for the refrigerator.
For example, a signal to turn on the refrigerator is input, and based on this signal, the balance valve is opened for the predetermined period of time, then the balance valve is stopped, and then the compressor is started. Further, the control device inputs a start signal for the compressor, opens the balance valve for a certain period of time, and then closes the balance valve.

Further, the refrigerant valve is a valve that closes the passage when the compressor is stopped and prevents refrigerant from flowing from the high pressure side to the low pressure side.

Further, the check valve on the discharge side of the compressor is a valve that prevents refrigerant discharged from the compressor from flowing back into the compressor.

[For production]

In the refrigerator of the present invention, when the temperature inside the freezer reaches a predetermined value (for example, -20°C) during cooling, the refrigerant valve closes and the compressor stops. At this time, the balance valve opens for several seconds to several tens of seconds due to the stop signal from the compressor.
The discharge side and suction side of the compressor are in communication, and the pressures on both sides are equalized. The operation of this balance valve is performed by a control device.

Therefore, while the compressor is stopped as described above, the refrigerant valve is in a closed state, 2 and the check valves are set i, l.
Therefore, refrigerant is prevented from flowing from the high pressure side (condenser side) to the low pressure side (evaporator and compressor suction side).

Although the above example shows the case where the balance valve is opened after the compressor is stopped, the balance valve can also be opened after the compressor is stopped and immediately before the next restart. The effect in this case is also the same as above.

〔effect〕

<2 According to the present invention, the pressures on the discharge side and the suction side of the compressor become balanced until the compressor is restarted, and a liquid hack in which liquid refrigerant accumulates in the evaporator is prevented. Does not occur.

When starting the compressor, the pressure on the discharge side is low and no liquid refrigerant flows into the suction side, so the load at startup is significantly reduced compared to conventional methods. Ru.

Furthermore, it is possible to improve the lifespan and reliability of the refrigerator.

As described above, according to the present invention, it is possible to provide a refrigerator with excellent startability and durability.

Further, when a three-way valve is used as the balance valve and the refrigerant passage can be switched to the condenser side or the evaporator side, in addition to the above effects, the three-way valve can also be used for defrosting.

〔Example〕

First Embodiment The refrigerator of this embodiment will be explained with reference to FIGS. 1 and 2.

The refrigerator is used for automobile freezers.

As shown in FIG. 1, compressor 91. Condenser 92 Throttle device 94. In addition to connecting the evaporator 95, a refrigerant valve 12 is also connected between the condenser 92 and the throttle device 94 on the discharge side 9 of the compressor.
12 has a check valve 13. These constitute a cooling system. Further, a balance valve 11 is provided on the outlet side of the check valve 13. The balance valve 11 is an electromagnetic three-way valve having a nozzle A opening into the check valve 13, a nozzle B connected to the condenser 92 side, and a nozzle C connected to the evaporator 95 side.

Although the balance valve 11 is originally intended to balance the pressure between the discharge side and the suction side when the compressor is stopped, it can also be used when defrosting the evaporator 95, as will be described later.

Thus, the compressor 91 is connected to the electromagnetic clutch 81 pulley 82 . ■Held 83. It is connected to an automobile engine 85 via a pulley 84 . In addition, the balance valve 11. Refrigerant valve 12. The electromagnetic clutch 81 and the engine 85 are each electrically connected to the control device 2.

Next, the functions and effects of the above-mentioned refrigerator will be explained.

That is, during the cooling cycle, the gaseous refrigerant discharged from the compressor 4191 passes through the check valve 13. Condenser 92 via nozzle AB of balance valve 11
It becomes thick and liquid. Further, the liquid refrigerant passes through the refrigerant valve 12 and is adiabatically expanded and cooled in the expansion device 94. The cooled refrigerant enters the evaporator 95 where it discharges cold air to the freezer and then to the suction side 9 of the compressor 91.
Enter 11. Note that the compressor 91 is driven by the engine 85 with the electromagnetic clutch 8I turned on.

Next, when the temperature inside the freezer reaches a set value (eg -20'C), this is detected, and the control device 2 stops energizing the refrigerant valve 12, thereby closing the refrigerant valve 12.

At the same time, the electromagnetic clutch 81 is turned off, and the compressor 91
stops.

At this time, the balance valve 11 is energized by the control device 2, the path between the nozzles A and C is opened, and the space between the nozzles A and B is closed, and the gaseous refrigerant discharged from the compressor 91 flows as shown by the dotted arrow. Without passing through the condenser 92 and throttle device 94,
It directly enters the evaporator 95.

In other words, the discharge side 912 of the compressor 91. The suction side 9]1 is in communication. The path opening of the nozzles A and C is performed for several seconds to several tens of seconds. Therefore, during this time, the pressures on the discharge side 912 and the suction side 911 are balanced.

After the path between the nozzles A and C is closed,
The space between nozzles A and B is opened again. Then, prepare for the second compressor startup. Note that until the next startup, the 2 high pressure side (condenser 92 side) is isolated from the low pressure side (evaporator 95 side) by closing the check valve 13 and refrigerant valve 12. Therefore, the liquid refrigerant on the high pressure side does not flow into the low pressure side.

Further, in the refrigerator of this example, when the evaporator 95 is defrosted (or heated), the balance valve 11 is switched in the direction of the nozzles A and C while the compressor 91 remains in operation. As a result, the refrigerant discharged from the compressor 91 is directly sent to the evaporator 95 as shown by the two-dot arrow. Since this refrigerant does not pass through the expansion device 94, it is not cooled and defrosts (or warms) the evaporator 95 by heating it.

Next, in the above refrigerator, the control flow when the freezer temperature (1) is cooled to the set temperature (td), the compressor 91 is stopped, and the pressure balance is performed will be explained using the flowchart in FIG. do. In addition, the control flow (831-537) at the time of defrosting is also shown in the same figure.

That is, 2. First, the desired set temperature td in the freezer is set (S
2), 31. A signal n-〇 indicating that S2 has been passed is set (S3), and then the internal temperature t of the freezer is detected (S4) L
, proceed to S5. Next, if it is determined in S5 that the temperature inside the refrigerator is also higher than the set temperature td, the refrigerant valve 12 is turned on (energized by the control device 2) to open the valve (S6
). Note that when t>td is not satisfied, the process returns to 34 and temperature detection is continued.

Next, the fans 921.95 of the condenser 92 and evaporator 95
1 is turned on (37), and when the passing signal n is determined to be n-0 (33 above) in S8, the electromagnetic clutch 81 for the compressor is turned on to drive the compressor 91 (s9). Further, in S8, if the signal n is n-1 (that is, the passing signal of 336 in the defrosting cycle described later), the clutch of the compressor 91 remains on, so the process proceeds to the first step 310.

Next, in S10, a defrosting cycle (83
1 to 537), the timer setting for the removal time is made,
When it is determined in S11 that it is not the defrosting time, the process proceeds to S12. Then, the temperature inside the refrigerator is also detected in step S], 2, and the temperature is set as the set temperature t in step S13.
If it has not decreased to d, the process returns to step 311 above.

Further, when the temperature inside the refrigerator reaches the set temperature td, the electromagnetic clutch 81 of the compressor 91 is turned off by the thermosknoto (314), the operation of the compressor 91 is stopped, and the condenser 92. 77792] and 951 of the evaporator 95 are also turned off (S15).

Further, the power to the refrigerant valve 12 is turned off and the valve is closed (316), and the balance valve 11 is powered for a certain period of time (for example, 10 seconds) to communicate with the nozzle AC side. Thereby, the discharge side 912 of the compressor 91 and the evaporator 95 are connected, and the pressures on the discharge side 912 and the suction side 911 of the pressure III compressor 91 are balanced.

Thus, the energization of the balance valve in S17 is completed,
That is, after the balance valve 11 communicates with the nozzles A and B, the defrost timer is reset at 818, and the process returns to S3. Then, the cooling cycle is performed again.

Next, in S11, when it is determined that the defrosting time has been reached, the process proceeds to S31, and the balance valve 11 is energized to connect the nozzle AC side with the condenser 92 and the evaporator while the compressor 91 is operating. The fans 921 and 951 of the device 95 are turned off (S32). Then, it is discharged from the compressor 91. The warm refrigerant is sent to the evaporator 95 for defrosting. In S33, the defrosting state is detected, and when it is determined in S34 that the defrosting has been completed, the process proceeds to S35, where the energization to the balance valve 11 is stopped and the nozzles A and B are communicated. Then, in step 536, the passage signal n-1 is set, and then the defrosting timer is reset (S37), and the process returns to S7. Then, the cooling cycle is performed again.

According to the refrigerator of this example, the discharge side and the suction side are communicated via the evaporator 95 for a predetermined time after the compressor is stopped, and the pressure between the two is balanced. During this time, communication between the high pressure side and the low pressure side is blocked by the refrigerant valve 12 and the check valve 13, so the liquid refrigerant on the high pressure side flows into the evaporator 95 and the suction side 91 of the compressor 91. Never.

Therefore, when the 10i pressure machine is started for the second time, the load on the compressor is significantly reduced, and the life reliability of the refrigerator is also improved.

Further, according to the two examples, the balance valve 11 can be used not only for pressure balance of the compressor but also for the defrosting cycle.

Second Embodiment The refrigerator of this embodiment will be explained with reference to FIGS. 3 and 4.

In this refrigerator, as shown in FIG. 3, first, a balance valve 31 for pressure balance is disposed between a discharge side 912 and a suction side 911 of the compressor.

A three-way valve 32 and an expansion bypass valve 34 are also provided for the defrost cycle.

The three-way valve 32 connects the nozzle E on the inlet side to the check valve 13 on the discharge side of the compression m91, one nozzle F on the outlet side connects to the inlet side of the condenser 92, and the other nozzle G connects to the inlet side of the condenser 92. It is connected after the check valve 33 provided on the outlet side of the. Further, the expansion bypass valve 34 is arranged to bypass the refrigerant valve 12 and the throttle device 94. Therefore, 1 the balance valve 31. The expansion bypass valve 34 is a solenoid valve and is electrically connected to the control device 2 . The rest is the same as the refrigerator of the first embodiment.

Next, the effects of the two examples will be explained.

First, when the compressor 91 stops as shown in the first embodiment, the control device 2 inputting the signal energizes the refrigerant valve 12 and the balance valve 31, closes the refrigerant valve 12, and closes the balance valve 31. open for a few seconds. Thereby, the discharge side 912 and the suction side 911 of the compressor 91 are communicated with each other, and the pressures therebetween are balanced. Further, at this time, the high pressure side and the low pressure side are separated by the closing of the refrigerant valve 12 and the check valve 13, so the liquid refrigerant on the high pressure side does not flow into the low pressure side.

On the other hand, when performing a defrosting cycle, while the 2 compressor 91 is operating, the 5 control device 2 opens the three-way valve to the nozzle E and G side, and at the same time, the expansion bypass valve 34 is opened so that the compressor discharges as shown by the dotted line arrow 9. Warm refrigerant to evaporator 95
send to After the defrost cycle is completed, turn the three-way valve 32 to nozzle E.
, return to the F side, close the expansion bypass valve 34, and continue the cooling cycle as shown by the solid arrow.

Next, the control flow in the refrigerator of this example will be explained using the flowchart of FIG. 4.

In this example refrigerator. Pressure balance operation (S1-518
) is the same except that the balance valve 31 that is energized and opened in S17 is an off-on valve, unlike the three-way switching system of the first embodiment, so a description thereof will be omitted.

On the other hand, regarding the defrosting cycle, if it is determined in Sll that it is time to defrost, the process proceeds to S41. Then, the expansion bypass valve 34 is energized to open the valve 341).
Also, the three-way valve 32 is energized to open the nozzles E and G sides (S42), and the fans 921 and 951 of the condenser 92 and evaporator 95 are turned off (S43). This results in
A defrost cycle is performed.

Then, defrosting detection is performed in S44, and when it is determined that defrosting has ended in S45, the energization to the three-way valve 32 is stopped, the nozzles E and F sides are opened (S46), and the expansion bypass valve 34 is Please stop energizing and close it.547
), the defrosting timer is reset (548), and the n=1 signal is set (349), returning to step 37. Then, the cooling cycle is performed again.

According to the refrigerator of this example, in addition to obtaining the same effects as in the first embodiment, the liquid refrigerant in the receiver 13 can be used for defrosting at the time of defrosting, compared to the first embodiment.

In addition, although the pressure balance operation 2 was performed after the compressor was stopped in the upper case, this operation can also be performed before starting the compressor as described above.

[Brief explanation of the drawing]

1 and 2 show a refrigerator of a first embodiment. Fig. 1 is an overall explanatory diagram, Fig. 2 is a flowchart, Figs. 3 and 4 show a refrigerator of the second embodiment, Fig. 3 is an overall explanatory diagram, Fig. 4 is a flowchart, and Fig. 5 is an explanatory diagram of the entire refrigerator. The figure is an overall explanatory diagram of a conventional refrigerator. 32. 34. 81. 9 I ・ ・ ・ 92, . 95. : One-way valve expansion bypass valve electromagnetic clutch compressor. Condenser Evaporator Applicant Japanese Employed

Claims (2)

[Claims] (1) In addition to connecting the compressor, condenser, throttle device, and evaporator, a refrigerant valve is installed between the condenser and the throttle device, and a check valve is installed on the discharge side of the compressor. a cooling system configured to circulate refrigerant; a balance valve that balances the pressure between the discharge side and the suction side of the compressor for a predetermined time when the compressor is stopped or started; and a balance valve that is linked to the operation of the compressor. A refrigerator comprising a control device that opens and closes the balance valve. (2) The refrigerator according to claim 1 is characterized in that the balance valve is a three-way valve and is configured to switch the refrigerant passage to the condenser side or the evaporator side in conjunction with the operation of the compressor. Freezer.