JPH0331514A - Operation of refrigerator - Google Patents

Abstract

PURPOSE:To shorten the operation time of a subengine by stopping the subengine when the operation in the same operation mode to that on the start on the operation of a refrigerator is stopped after the completion of the charge for a battery, in the constitution in which the refrigerator is driven by the subengine. CONSTITUTION:In an endothermic operation, cooling operation is instructed at the upper limit temperature T1 on a thermostat, in a controller 14, and an engine 1 is started, and a battery 16 is charged by a power generator 15, and at the same time, a refrigerator is cooling-operated. When the temperature T lowers, and reaches a set temperature Ts, an instruction for selecting the heating operation is generated, and the temperature in a cooling box is raised by the heating operation of the refrigerator, and when the upper limit temperature T1 of a thermostat TH1 is reached, an instruction for selecting cooling operation is generated. When the charging for the battery is completed in such the refrigerator, operation mode on the start of operation is controlled so that the engine 1 is stopped on the completion of the cooling operation.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method of operating a refrigeration apparatus such as a refrigeration unit for land transportation driven by a sub-engine.

(Prior Art) An example of a refrigerant circuit of this type of refrigeration system is shown in FIG.

In FIG. 6, 1 is an engine, 2 is a compressor driven by the engine 1, and 3 is a three-way valve, which is driven by a solenoid 4 to switch between cooling operation and heating operation.

5 is a capacitor, and 6 is a fan for blowing outside air to the capacitor 5, which is driven by a motor 7. 8 is an expansion valve, 9 is an evaporator installed in the freezer/refrigerator, 1
0 is a fan for blowing air inside the refrigerator to the evaporator 9, and is driven by a motor 11. 12 is a check valve;
13 is a thermosensor that detects the temperature inside the freezer/refrigerator;
14 is a control device, 15 is a generator driven by the engine 1, 16 is a battery charged by the generator 15, and 17 is a sensor that detects the amount of charge of the battery 16.

During cooling operation, the high-temperature, high-pressure refrigerant gas discharged from the compressor 2 passes through the three-way pulp 3 and enters the condenser 5, as shown by the solid arrow, where it undergoes heat exchange with the outside air sent by the fan 6. 'a Condensation liquefies and becomes a low temperature, high pressure liquid refrigerant. This liquid refrigerant enters the expansion valve 8, where it is throttled and expands adiabatically to become a gas-liquid two-phase at low temperature and low pressure. Next, this gas-liquid two-phase refrigerant enters the evaporator 9, where it evaporates and vaporizes by cooling the indoor air sent by the fan 1O, becoming a low-temperature, low-pressure refrigerant gas. This refrigerant gas is then sucked into the compressor 2 and compressed again.

During heating operation, the refrigerant returns to the compressor 2 through the compressor 2, three-way valve 3, check valve 12, expansion valve 8, and evaporator 9 in this order, as shown by the broken line arrow.

The outputs of the thermosensor 13 and the sensor 17 are sent to the control device 14.
The engine 1, solenoid 4, motor 7, and motor 11 are controlled by commands from the control device 14.

Fig. 7 (A) shows an operation switching diagram of this refrigeration system, and Fig. 7 (B) shows a switching diagram of THI and TH2 (thermo sensors built into the control device 14). As shown in Figure 7 (B), THI is
It turns OFF when the internal temperature T reaches the set temperature T, and turns ON when it reaches the upper limit temperature T1. Further, the thermostat TH2 is turned OFF when the internal temperature T reaches the set temperature T, and is turned ON when the temperature T reaches the lower limit temperature T.

Therefore, when the load is a cooling load, heat absorption operation shown by the solid line in FIG. 7(A) is performed, and when the load is a heating load, the heat radiation operation shown by the broken line in FIG. 7(A) is performed. .

During endothermic operation, the internal temperature T of the refrigerator is at point A in FIG. 7(A), that is,
When the upper limit temperature T of thermostat T) II is reached,
The engine 1 is started by a command from the control device 14, and the generator 15 starts charging the battery 16, and at the same time, the refrigeration system starts cooling operation.

When the internal temperature T gradually decreases due to the cooling operation of the refrigeration system and reaches the set temperature T, that is, at the mouth point,
A command to switch from cooling operation to heating operation is output. When the internal temperature T rises due to the heating operation of the refrigeration equipment and reaches the upper limit temperature T of the thermosensor THI,
A command to switch from heating operation to cooling operation is output. In this way, unless there is a signal indicating that the battery 16 is sufficiently charged, the refrigeration system maintains the internal hot water temperature T near the set temperature T while alternately operating the cooling operation and the heating operation.

While the engine 1 is running, the generator 15 continues to charge the battery 16, and when a signal indicating that the battery 16 is sufficiently charged is output from the sensor 17, for example at point C, the engine 1 immediately stops. . After the refrigeration system is stopped, the internal temperature T gradually rises due to heat intrusion into the refrigerator from the outside, heat generated by the frozen object, etc., and reaches the upper limit temperature T of the thermostat THI. Operation of engine 1 is resumed at point °.

When the load is a heating load, the heat dissipation operation shown by the broken line in Fig. 7 (A) is performed, and when the internal temperature T reaches the lower limit temperature T of thermostat TI (2), the heating operation is commanded, and the set temperature T When reaching , the heating operation is switched to the cooling operation.The other operations are the same as in the endothermic operation.

(Problems to be Solved by the Invention) In the conventional method described above, when the sensor 17 outputs a signal indicating that the battery 16 is sufficiently charged, the engine 1 is immediately stopped, and the refrigeration system is And the generator 15 also stops.

Therefore, as shown in FIG. 7(A), when the engine 1 is stopped at point C during heating operation of the refrigeration system, the temperature difference between the internal temperature T and the upper limit temperature T at this point is small, and The internal temperature T due to overshoot due to heating operation
When the internal temperature T rises and reaches the upper limit temperature T1, the cooling operation is restarted at point A. As a result, the stop time of engine 1 is the time from point E to point I, and the operating time of engine I is from point A to point E. As a result, the operating rate (operating time/stopping time) of the engine 1 increases, resulting in a problem of high fuel consumption.

(Means for Solving the Problems) The present invention was invented to solve the above problems, and the gist thereof is to cool a refrigeration system driven by an engine together with a generator for battery charging. In an operating method in which the temperature of the frozen object is controlled by alternately repeating operation and heating operation, and the engine is stopped after the charging of the battery is completed, after the charging of the battery is completed, the refrigeration system is in the same operating mode as when the operation is started. A method of operating a refrigeration system is characterized in that the engine is stopped when the operation of the refrigeration system is completed.

(Function) Since the present invention has the above configuration, the engine continues to operate while the battery is insufficiently charged, and the refrigeration system alternately repeats cooling operation and heating operation to cool the frozen object. Maintain temperature near set point.

The engine does not stop immediately when a signal indicating that battery charging is completed is output, but the engine stops when the refrigeration system finishes operating in the same operating mode as when it started operating.

(Embodiment) An embodiment of the present invention is shown in FIGS. 1 and 2, where FIG. The figure is a flowchart.

The refrigerant circuit of the refrigeration system is similar to the conventional one shown in FIG.
I and TI (2) are built in, and this switching diagram is shown in Figure 1 (B
), it is similar to the conventional one. And the first
In the operation switching diagram in Figure (A), the solid line is during endothermic operation;
The broken line shows the line during the heat dissipation operation, but since the line during the heat dissipation operation is the same as that during the heat absorption operation, the heat absorption operation will be specifically explained below.

During the endothermic operation, the control device 14 commands the cooling operation at point A, that is, at the upper limit temperature T of the thermocouple THI.

Then, the engine 1 starts, the engine T1m15 starts charging the battery 16, and at the same time, the refrigeration system starts cooling operation.

The internal temperature T gradually decreases due to the cooling operation of the refrigeration system, and when it reaches the set temperature T, that is, at point 0,
A command to switch from cooling operation to heating operation is output.

When the internal temperature T rises due to the heating operation of the refrigeration system and reaches the upper limit temperature T of the thermostat TI, a command to switch from the heating operation to the cooling operation is output.

By alternately repeating the cooling operation and heating operation described above, the refrigeration system maintains the internal temperature T in the vicinity of the set temperature T.

While the engine 1 is running, the power generation atS continues to charge the battery 16, and if a signal indicating that the battery 16 is sufficiently charged is output from the sensor 17 at point C, for example, the engine 1 will start heating operation without stopping immediately. Continue. As a result of this heating operation, the temperature T in the refrigerator reaches the upper limit temperature T of the thermostat T) 11, and at two points the engine 1 switches to the cooling operation. will be stopped. That is, during the endothermic operation, the engine 1 is started in the cooling operation, so the engine 1 is stopped at the end of the cooling operation. After the engine 1 is stopped, the temperature T in the refrigerator gradually rises due to the heat entering the refrigerator and the heat generated by the frozen object, and when it reaches a point 1, the engine 1 is started again and cooling operation is started.

In this way, even after the command to complete charging is output to the pantry 16, the engine 1 does not stop immediately, and the operating mode of the refrigeration system becomes the operating mode at the start of operation, that is, cooling operation, and at the end of this cooling operation. Since the engine 1 is stopped, the operating time of the engine 1 is from point A to point H, and the stopping time of the engine 1 is from point H to point I.

As a result, the operating rate of engine 1 (operating time/stopping time)
is smaller, so fuel consumption is reduced.

FIG. 3 shows an operation switching diagram of a refrigeration system according to a second embodiment of the present invention.

In this second embodiment, as shown in the figure, when a signal indicating that charging of the battery 16 is completed is output at a point during the heating operation, the operation is immediately switched to the cooling operation.

Then, the engine 1 is stopped at the point where the internal temperature T reaches the set temperature T.

In this second embodiment, the operating time of the engine 1 is from point A to point H, and the operating time of the engine I is even shorter than that of the first embodiment. Furthermore, since the stop time of the engine 1 is the same as in the first embodiment, the operating rate of the engine 1 is even smaller than in the first embodiment. Other configurations and operations are the same as in the first embodiment.

A third embodiment of the invention is shown in FIG.

Figure 4 (A) is an operation switching diagram of the refrigeration system, Figure 4 (B)
is a switching diagram of a thermostat.

As shown in FIG. 4(B), the control device 14 includes, in addition to the thermostats Tl1l and TI+2, a third thermostat TH3 having an upper limit temperature T and a lower limit temperature T4.

During the endothermic operation, the refrigeration system starts cooling operation at point A, and switches to heating operation at point B when the internal temperature T reaches the lower limit temperature T4 of Thermostough TI+3.

Then, by this heating operation, the temperature T inside the refrigerator rises, and at a point when the temperature T reaches the upper limit temperature T of the thermostat TH3, the operation is switched to the cooling operation. In this way, the refrigeration system maintains the internal temperature T near the set temperature T by alternately repeating the cooling operation and the heating operation between the lower limit temperature T4 and the upper limit temperature T3 of the thermostat TH3.

Now, if a command indicating that charging of the battery 16 is completed is output at point C during heating operation, the refrigeration system continues heating operation, switches to cooling operation at point T, and ends this cooling operation. At 1,000 points, engine 1
stops.

In this third embodiment, the operating time of the engine 1 is from point A to the child, and the stop time of the engine I is from the 1,000 point to the point A, so the operating rate of the engine 1 is further reduced. Other configurations and operations are the same as in the first embodiment.

FIG. 5 shows a fourth embodiment of the invention.

In this fourth embodiment, when a command to the effect that charging of the battery 16 is completed is output at point C during heating operation, the cooling operation is immediately switched to 1, and at the end of this cooling operation, At this point, the operation of the engine 1 is stopped.

In the fourth embodiment, the operating time of the engine l is from point A to the child, which is even shorter than that of the third embodiment, so that the operating rate of the engine l is further reduced.

Other configurations and operations are similar to those of the third embodiment.

The case where the present invention is used to control the temperature of a refrigerator has been described above, but when the present invention is used to control the temperature of a freezer, the heat dissipation operation becomes unnecessary, and therefore, the thermostat T112 is also unnecessary.

(Effects of the Invention) In the present invention, the engine is stopped when the refrigeration system finishes operating in the same operating mode as when it started operating after the battery is charged, so the temperature of the frozen object when the engine is stopped is The difference between the temperature of the refrigerated object and the temperature of the frozen object at the time of resumption of operation becomes large (and the engine stop time becomes long).As a result, the operating rate of the engine decreases, so fuel consumption can be reduced.

[Brief explanation of drawings]

FIG. 1 and FIG. 2 show a first embodiment of the present invention.
Figure (A) is an operation switching diagram of the refrigeration system, Figure 1 (CB) is a switching diagram of the thermostat, and Figure 2 is a control flowchart. FIG. 3 is an operation switching diagram of a refrigeration system showing a second embodiment of the present invention. FIG. 4 shows a third embodiment of the present invention, and FIG. 4(A) is an operation switching diagram of the refrigeration system.
Figure (B) is a switching diagram of the thermostat. FIG. 5 is an operation switching diagram of a refrigeration system showing a fourth embodiment of the present invention. Figures 6 and 7 show an example of a conventional refrigeration system, where Figure 6 is a system diagram, Figure 7 (A) is a diagram of operation switching of the refrigeration equipment, and Figure 7 (B) is a diagram of switching of a thermostat. It is. Engine--1, Battery-16, Generator--
] 5, Capacitor - 5, Expansion valve - 8, Evaporator - 9, Control device - 14, Thermo sensor - 13, Charge amount detection sensor - 17, Thermostat - THI, T112, TH3 Fig. 2 , Indication of the case 1999 Patent Application No. 166413 2 Name of the invention Operating method of refrigeration equipment 3 Person making the amendment Relationship to the case Patent applicant address 2-5-1 Marunouchi, Chiyoda-ku, Tokyo Name (
620) Mitsubishi Heavy Industries, Ltd. 4, Agent address ■105 Nishi-Shinbashi-chome 18-15-6, Minato-ku, Tokyo
, Description and drawing 7 subject to amendment, Contents of amendment ■) "2 Detailed description of the invention" in the 3rd line of page 1 of the specification is amended to read "2 claims." 2) Amend "3 claims" on page 1, line 13 of the specification to "3 detailed description of the invention." 4) On page 3, line 6 of the specification, “Gas is compressor 2.
Correct j to ``Gas passes through suction pressure adjustment valve 12 to compressor 2''. 5) "Three-way valve 3, check valve 12, expansion valve 8, evaporator 9" on page 3, line 9 to line 10 of the specification
"in this order" to "correct the three-way valve 3, evaporator 9, and suction pressure adjustment valve 12 to j in this order. 6) Specification, page 6, line 17, and page 1O, lines 13 to 14 Correct "(operating time/I! i stop time)" J to "(operating time)". 7) Correct "Heat penetrating into the refrigerator" on the second line of the statement No. 1 to "Heat penetrating into the refrigerator." 8) In the fourth line of page 13 of the specification, "at my son" is amended to "at my son." 9) Please make the following corrections from line 11 to line 14 on page 13 of the specification. In the above embodiment, the sensor 17 detects the completion of charging of the battery 16 and outputs a charging completion signal, but this may be replaced with a signal based on the time-up of the charging timer, that is, the set time of the charging timer. The time required to charge the battery is set to a value determined in advance through tests, and the charging timer starts counting at the same time as the engine starts, and the charging timer's time amplifier assumes that charging is complete and outputs a charging completion signal. 10) Correct Figure 6 as shown in the attached sheet. 8. Attached document drawings (Fig. 6) 1 copy Fig. 6

Claims (1)

[Claims] In the operating method, the temperature of the frozen object is controlled by alternately repeating cooling operation and heating operation of a refrigeration system driven by an engine together with a generator for charging the battery, and the engine is stopped after charging of the battery is completed. 1. A method of operating a refrigeration system, comprising: stopping the engine when the refrigeration system finishes operating in the same operating mode as when it started operating after completion of charging.