RU2482402C1 - Conditioner - Google Patents

Abstract

FIELD: ventilation.

SUBSTANCE: conditioner (1) for implementation of the refrigeration cycle by comprising at least a compression mechanism (21), an internal heat exchanger (41), an internal ventilator (42), an external electric expansion valve (24), and an external heat exchanger (23). The conditioner (1) comprises a winding (68), an electromagnetic induction thermo-resistor (14) and a control unit (11). The winding (68) generates a magnetic field to heat through the tube induction (F2), made of a magnetic material, in order to heat the refrigerant flowing through the accumulation tube (F). The electromagnetic induction thermo-resistor (14) measures the temperature of the tube (F2) made of a magnetic material which generates heat by induction heating using the winding (68). The control unit (11) exercises control to increase the degree of opening of the electric expansion valve (24) when the rate of increase of the temperature measured by electromagnetic induction thermo-resistor (14) is high.

EFFECT: use of the invention enables to exercise the control, which takes into account the amount of heat added to the refrigerant which is absorbed into the compression mechanism during regulation of the degree of the refrigerant superheating, even when the refrigerant is heated on the suction side of the compression mechanism.

7 cl, 16 dwg

Description

FIELD OF THE INVENTION

The present invention relates to an air conditioner.

BACKGROUND OF THE INVENTION

Air conditioners are known in common practice in which the amount of refrigerant for circulation or the like is controlled to control the degree of overheating of the refrigerant sucked into the compressor.

For example, in an air conditioner disclosed in Patent Literature 1 (published Japanese Patent Laid-open No. 7-120083), the amount of refrigerant for circulation can increase and the degree of overheating of the refrigerant sucked into the compressor can be controlled by controlling so that the degree of opening of the electrical expansion valve increases according to the temperature of the refrigerant sucked into the compressor.

SUMMARY OF THE INVENTION

<Technical Problem>

There are known cases in which, on the compressor inlet side, the refrigerant sucked into the compressor is indirectly heated by using an external heating device to heat the refrigerant pipe or the like in thermal contact with the refrigerant.

In cases where such an external heating device is used, when, for example, a refrigerant temperature sensor at the compressor inlet is located between the section to be heated by the external heating device and the compressor inlet side, the heat applied to the section heated by the external heating device due to the heat The contact is transferred to the vicinity where the refrigerant temperature sensor is fixed at the inlet downstream, making it difficult to accurately measure the temperature of the refrigerant at the inlet. When adjusting the degree of opening of the electric expansion valve, which is based on the value measured by the refrigerant temperature sensor at the compressor inlet, located between the section heated by the external heating device and the compressor inlet side, there is a risk that the valve opening degree will be greatly increased and the amount of refrigerant for circulation will increase much, and not only will an excessive increase in the degree of overheating of the refrigerant sucked into the compress be minimized p but will also occur compressive fluid.

When, for example, a section heated by an external heating device is located so as to be downstream from the measurement position of the refrigerant temperature sensor at the compressor inlet and upstream from the compressor inlet side, it is not possible to determine the temperature of the refrigerant at the inlet that heats up as it passes through the heated section. When adjusting the degree of opening of the electrical expansion valve, which is based on the value measured by the inlet refrigerant temperature sensor located upstream of the portion heated by the external heating device, there is a risk that the degree of opening of the valve will be greatly reduced and the amount of refrigerant to be circulated will be decrease much, and the degree of overheating of the refrigerant sucked into the compressor will increase excessively.

The present invention was conceived in view of the circumstances described above, and its purpose is to provide an air conditioner capable of controlling the amount of heat applied to the refrigerant in the inlet while controlling the degree of overheating of the refrigerant sucked into the compression mechanism, even when the refrigerant is heated on the inlet side compression mechanism.

<Problem Solving>

An air conditioner in accordance with a first aspect is an air conditioner that includes at least a compression mechanism, a device for cooling a refrigerant, an expansion mechanism and a device for heating a refrigerant, the air conditioner comprising a magnetic field generator, a temperature sensor for the heat generated and a control unit. The magnetic field generator generates a magnetic field for induction heating the refrigerant pipe to circulate the refrigerant into a compression mechanism, a refrigerant cooling device, an expansion mechanism and a device for heating the refrigerant and / or an element in thermal contact with the refrigerant passing through the refrigerant pipe. The temperature sensor of the released heat measures the temperature of the portion that generates heat due to induction heating by the magnetic field generator. The control unit controls overheating protection to increase the degree of opening of the expansion mechanism, or when the temperature measured by the temperature sensor of the released heat reaches or exceeds the set temperature of the released heat, or when the rate of increase of the temperature measured by the temperature sensor of the generated heat reaches or exceeds the set increase rate .

In this air conditioner, since a temperature sensor for the released heat is provided, it is possible to determine the temperature of the area where the heat is generated by induction heating the magnetic field generator. By controlling the overheating protection provided by the control unit, the opening degree of the expansion mechanism increases and the amount of refrigerant supplied to the inlet side of the compression mechanism increases when either the temperature measured by the heat-generating temperature sensor reaches or exceeds a predetermined heat-generating temperature, or the rate of temperature increase measured by the temperature sensor of the released heat reaches or exceeds a predetermined rate of increase. Therefore, it is possible to minimize an excessive increase in the degree of overheating of the refrigerant sucked into the compression mechanism. Thus, it is possible to control the degree of overheating of the refrigerant sucked into the compression mechanism, taking into account the amount of heat applied to the sucked-in refrigerant, even when the refrigerant is heated on the inlet side of the compression mechanism.

An air conditioner in accordance with a second aspect is an air conditioner in accordance with a first aspect, wherein the magnetic field generator generates a magnetic field for induction heating the refrigerant pipe in the inlet inside the refrigerant pipe on the inlet side of the compression mechanism and / or the element in thermal contact with the refrigerant passing through the inlet refrigerant pipe.

In this air conditioner, the refrigerant immediately heats up immediately before being sucked into the compression mechanism, rather than the refrigerant passing through the refrigerant pipe a certain distance from the compression mechanism. The refrigerant passing through the inlet side of the compression mechanism is either very dry or superheated, and compared to cases in which the latent heat of a gas-liquid two-phase refrigerant changes further upstream, it is easy to cause a change in dry heat, and therefore the temperature rising fast.

In this air conditioner, since the overheating protection is controlled either when the temperature measured by the temperature sensor of the released heat reaches or exceeds a predetermined temperature of the generated heat, or when the rate of increase of the temperature measured by the temperature sensor of the generated heat exceeds a predetermined rate of increase, excessive induction heating of the refrigerant passing through the inlet side of the compression mechanism. Thus, even in the case of the heating of the refrigerant passing through the inlet side of the compression mechanism, with the rapid occurrence of a rise in temperature, it is possible to reduce the excessive heating of the area heated by induction.

An air conditioner in accordance with a third aspect is an air conditioner in accordance with the first or second aspect, wherein the control unit controls at startup and control after startup. During start-up control, a magnetic field generator generates a magnetic field, so that the temperature of the area where heat is generated by induction heating by the magnetic field generator reaches a predetermined target temperature at start-up, while the compression mechanism starts to operate from the off state of the compression mechanism. Management after startup is carried out after management is completed at startup. When controlling overheating protection, control is simultaneously carried out after start-up, the control unit increases the degree of opening of the expansion mechanism when the temperature measured by the temperature sensor of the released heat reaches or exceeds the set temperature of the generated heat after start-up. This predetermined temperature of the released heat after start-up is a temperature equal to or higher than the set target temperature at start-up. The set temperature of the heat generated after start-up can also be a temperature that is simply equal to the set target temperature at start-up.

In this air conditioner, when controlled after start-up, the degree of opening of the expansion mechanism increases when the temperature of the section that generates heat due to induction heating rises and reaches or exceeds the set temperature of the generated heat after start-up, resulting in the temperature of the section that generates heat due to induction heating may be reduced. Therefore, during post-start control, it is possible to reduce the excessive temperature rise of the portion that generates heat through induction heating.

When the set temperature of the released heat after start-up is not the temperature equal to the set target temperature at start-up, but is the temperature above the set target temperature at start-up, and even when the process is carried out to stop or reduce the supply of the magnetic field by the magnetic field generator, when the temperature of the section that generates heat due to induction heating, the time interval during which the temperature of the refrigerant can be maintained by induction on roar can be further increased.

An air conditioner in accordance with a fourth aspect is an air conditioner in accordance with a third aspect, in which when controlling overheating protection, it is simultaneously controlled at start-up, the control unit increases the opening degree of the expansion mechanism when the rate of increase in temperature measured by the temperature-generating heat sensor at that moment the time when the set target temperature at startup is reached, reaches or exceeds the set increase rate.

In this air conditioner, during start-up control, the opening degree of the expansion mechanism increases when the temperature measured by the temperature sensor of the released heat increases fast enough so that the rate of temperature increase reaches or exceeds the set rate of increase. During control after start-up, the opening degree of the expansion mechanism increases when the temperature measured by the temperature sensor of the released heat reaches or exceeds the set temperature of the generated heat. Therefore, since the determination is carried out on the basis of the measured temperature during control after start-up, however, in fact, the determination is based on the rate of increase in temperature during control at start-up, the degree of opening of the expansion mechanism increases at the time when the increase speed either reaches or exceeds the set speed increases, even when a rapid increase in temperature is caused during start-up, therefore, when reaching or exceeding the set speed, After reaching the set temperature of the released heat, it is not necessary to wait for the process to increase the degree of opening of the expansion mechanism until the set temperature of the released heat is reached. Therefore, a large amount of refrigerant can be more reliably supplied to a site that generates heat by induction heating. Thus, it is possible to reduce the amount by which the temperature rises steadily in the area that generates heat due to induction heating.

An air conditioner in accordance with a fifth aspect is an air conditioner in accordance with a fourth aspect, wherein, when determining that a predetermined increase rate has been reached or exceeded, the control unit increases the opening degree of the expansion mechanism only when the rotation speed of the compression mechanism reaches or exceeds the predetermined rotation speed.

In this air conditioner, there are cases in which the temperature increase rate of the portion that generates heat due to induction heating reaches or exceeds a predetermined increase speed when a state is provided in which the rotation speed of the compression mechanism reaches or exceeds a predetermined rotation speed. Even in such cases, the amount of refrigerant for circulation can be more reliably increased by increasing the degree of opening of the compression mechanism in a state in which the state of activation of the compression mechanism is ensured.

An air conditioner in accordance with a sixth aspect is an air conditioner in accordance with any of the third to fifth aspects, further comprising a unit for determining a state of a refrigerant on a side of a cooling device for determining a state of a refrigerant passing through a device for cooling a refrigerant into an expansion mechanism. Upon completion of control at startup, the control unit starts controlling the setting of the degree of subcooling to control the degree of opening of the expansion mechanism, so that the degree of subcooling of the refrigerant, determined using the value determined by the node to determine the state of the refrigerant on the side of the cooling device, is maintained unchanged at a given target degree of subcooling. In addition, when controlling overheating protection is simultaneously controlled, the setting of the degree of subcooling is controlled, the control unit additionally increases the degree of opening of the expansion mechanism as compared to the degree of opening controlled by controlling the setting of the degree of subcooling when the temperature measured by the temperature sensor of the generated heat reaches or exceeds the temperature of the generated heat when controlling the installation of a given degree of hypothermia. The temperature of the generated heat when controlling the installation of a given degree of subcooling is a temperature equal to or higher than a predetermined target temperature at startup.

In this air conditioner, it is possible to minimize excessive temperature increases in the portion that generates heat by induction heating, even when the degree of subcooling is controlled.

<Invention Results>

In an air conditioner, in accordance with a first aspect, it is possible to control the degree of overheating of the refrigerant, the heat released into the compression mechanism by taking into account the amount of heat applied to the sucked-in refrigerant, even when the refrigerant is heated on the inlet side of the compression mechanism.

In an air conditioner in accordance with the second aspect, it is possible to minimize excessive heating of the portion heated by induction, despite heating the refrigerant passing through the inlet side of the compression mechanism, which rapidly increases the temperature.

In an air conditioner in accordance with a third aspect, an excessive increase in the temperature of a portion that generates heat by induction heating can be reduced by control after start-up.

In the air conditioner in accordance with the fourth aspect, it is possible to reduce the amount by which the temperature is steadily increasing in the area that generates heat due to induction heating.

In an air conditioner in accordance with a fifth aspect, the amount of refrigerant for circulation can be more reliably increased.

In an air conditioner in accordance with a sixth aspect, it is possible to minimize excessive temperature increases of the portion that generates heat by induction heating, even when the degree of subcooling is controlled.

Brief Description of the Drawings

1 is a diagram of a refrigerant circuit of an air conditioner in accordance with an embodiment of the present invention.

Figure 2 is an external perspective view of an electromagnetic induction device.

Figure 3 is an external perspective view showing a state in which the protective cover is removed from the electromagnetic induction device.

Figure 4 is an external perspective view of an electromagnetic induction thermistor.

5 is an external perspective view of a fuse.

6 is a schematic sectional view showing a fixed state of an electromagnetic induction thermistor and a fuse.

7 is a view in section of the design of the electromagnetic induction heating device.

Fig. 8 is a view showing details of magnetic flux.

9 is a view showing various state transitions of an overheat protection control.

10 is a view showing a flow chart of controlling an overheat protection.

11 is a view showing a flowchart of regularly controlling overheating protection.

12 is an explanatory view of a refrigerant tube of another embodiment (E).

13 is an explanatory view of a refrigerant pipe of another embodiment (F).

14 is a view showing an example of arrangement of windings and a refrigerant pipe of another embodiment (G).

Fig. 15 is a view showing an example of arrangement of coil covers of another embodiment (G).

16 is a view showing an example of the arrangement of ferrite shells of another embodiment (G).

Description of Embodiments

An air conditioner 1 comprising an electromagnetic induction heating device 6 in one embodiment of the present invention is described in the example below with reference to the drawings.

<1-1> Air conditioning 1

1 is a schematic diagram of a refrigerant circuit showing a refrigerant circuit 10 of an air conditioner 1.

In the air conditioner 1, the external unit 2 as a device on the side of the heat source and the internal unit 4 as a device on the side of use are connected by means of refrigerant pipes, and air conditioning is carried out in the space in which the device is located on the side of use, and the air conditioner 1 comprises a compressor 21, four-way switching valve 22, external heat exchanger 23, external electric expansion valve 24, accumulator 25, external fans 26, internal heat exchanger 41, internal fan 42, hot gas bypass valve 27, capillary tube 28, electromagnetic induction heating device 6 and other elements.

Compressor 21, four-way switching valve 22, external heat exchanger 23, external electric expansion valve 24, accumulator 25, external fans 26, hot gas bypass valve 27, capillary tube 28 and electromagnetic induction heating device 6 are located in the outdoor unit 2. Internal heat exchanger 41 and the internal fan 42 is located in the internal node 4.

The refrigerant circuit 10 comprises an exhaust pipe A, a gas pipe B on the inside, a liquid pipe C on the inside, a liquid pipe D on the outside, a gas pipe E on the outside, a storage pipe F, an inlet pipe G and an overflow circuit H for hot gas. The gas pipe B on the inside and the gas pipe E on the outside allow large amounts of gaseous refrigerant to pass through, but the passing refrigerant is not limited to the gaseous refrigerant. The liquid pipe C on the inside and the liquid pipe D on the outside allow large quantities of refrigerant to pass in the liquid state, but the passing refrigerant is not limited to the liquid refrigerant.

The exhaust pipe A connects the compressor 21 and the four-way switching valve 22. The exhaust pipe A comprises an outlet temperature sensor 29d for measuring the temperature of the passing refrigerant. The electric current supply unit 21e supplies electric current to the compressor 21. The amount of electricity supplied by the electric current supply unit 21e is measured by the compressor electricity sensor 29f. The rotational speed of the piston drive of the compressor 21 is measured by the node 29r to determine the rotational speed. A gas pipe B on the inner side connects the four-way switching valve 22 and the internal heat exchanger 41. The first pressure sensor 29a for measuring the pressure of the passing refrigerant is located at some point along the gas pipe B on the inner side. A fluid pipe C on the inner side connects the internal heat exchanger 41 and an external electrical expansion valve 24. A fluid pipe D on the outer side connects the external electric expansion valve 24 and an external heat exchanger 23. A gas pipe E on the outer side connects the outdoor heat exchanger 23 and a four-way changeover valve 22. The second pressure sensor 29g for measuring the pressure of the passing refrigerant is located at some point along the gas pipe E on the outside.

The accumulation tube F connects the four-way switching valve 22 and the accumulator 25 and extends vertically when the outdoor unit 2 is installed. An electromagnetic induction heating device 6 is fixed to the part of the accumulation tube F. A portion for generating heat of the accumulation tube F, the perimeter of which is closed at least winding 68, described below, consists of a copper tube F1 through which refrigerant passes and a magnetic tube F2 located to close the periphery of the copper tube F1. This magnetic tube F2 consists of 430 stainless steel. 430 stainless steel is a ferromagnetic material that generates eddy currents when placed in a magnetic field and which generates heat due to the Joule heat generated by its own electrical resistance. Away from the magnetic tube F2, the tubes forming the refrigerant circuit 10 are composed of copper tubes of the same material as the copper tube F1. By performing electromagnetic induction heating in this way, the storage tube F can be heated by electromagnetic induction and the refrigerant passing into the compressor 21 through the accumulator 25 can be heated. The heating ability of the air conditioner 1 can thus be improved. Even in cases in which the compressor 21, for example, is not sufficiently heated at the beginning of the air heating process, the lack of start-up ability can be compensated for by quick heating using the electromagnetic induction heating device 6. In addition, when the four-way switching valve 22 is switched to the state of the air cooling process and the defrosting process is carried out to remove hoarfrost deposited on the external heat exchanger 23 or other elements, the compressor 21 can quickly compress rety refrigerant as a target due to rapid heating by means of electromagnetic induction heating unit 6 accumulative pipe F. Consequently, the temperature of the hot gas discharged from the compressor 21 may rise rapidly. Thus, the time required to melt the frost through the defrosting process can be reduced. Thus, even when the defrosting process must be carried out at the right time during the air heating process, the air heating process can be resumed as quickly as possible and the user comfort can be improved.

The inlet pipe G connects the accumulator 25 and the inlet side of the compressor 21.

A hot gas bypass circuit H connects a branch point A1 located at some point along the outlet pipe A and a branch point D1 located at some point along the liquid pipe D on the outside. At some point in the hot gas bypass circuit H, there is a hot gas bypass valve 27 that can switch between the state of passage of refrigerant and the state of blocking of passage of refrigerant. Between the hot gas bypass valve 27 and the branch point D1, the hot gas bypass circuit H comprises a capillary tube 28 to lower the pressure of the passing refrigerant. This capillary tube 28 makes it possible to approximate the pressure that follows the decrease in refrigerant pressure caused by the external electric expansion valve 24 during the air heating process and, therefore, makes it possible to prevent the increase in the refrigerant pressure in the liquid pipe D on the outside due to the supply of hot gas through the hot gas bypass circuit H to the liquid pipe D on the outside.

The four-way switching valve 22 is capable of switching between the cycle of the air cooling process and the cycle of the air heating process. 1, the state of the connection during the process of heating the air is shown by solid lines and the state of the connection during the process of cooling the air is shown by dashed lines. During the process of heating the air, the internal heat exchanger 41 performs the function of a device for cooling the refrigerant and the external heat exchanger 23 performs the function of a device for heating the refrigerant. During the air cooling process, the external heat exchanger 23 performs the function of a device for cooling the refrigerant and the internal heat exchanger 41 performs the function of a device for heating the refrigerant.

One end of the external heat exchanger 23 is connected to the end of the gas pipe E on the outer side of the external heat exchanger 23, the other end is connected to the end of the fluid pipe D on the outer side of the external heat exchanger 23. The external heat exchanger 23 also includes an external heat exchange temperature sensor 29c for measuring the temperature of the refrigerant passing through the air conditioner 1. In addition, the upstream side of the outdoor heat exchanger 23 in the air flow direction includes an outside temperature sensor 29b for measuring temperature outdoor air atura.

An indoor temperature sensor 43 for measuring indoor temperature is located in the indoor unit 4. The internal heat exchanger 41 also includes an internal heat exchange temperature sensor 44 for measuring the temperature of the refrigerant from the side of the fluid pipe C on the inside, where the external electrical expansion valve 24 is connected.

The outdoor control unit 12 for controlling devices located in the external unit 2, and the internal control unit 13 for controlling devices located in the internal unit 4, are connected via a communication line 11a, thereby forming a control unit 11. This control unit 11 carries out various controls of the air conditioner 1.

The outdoor control unit 12 also includes a timer 95 for counting the time used during various controls.

The controller 90 for receiving installation input data from the user is connected to the control unit 11.

<1-2> Electromagnetic induction heating device 6

Figure 2 is a schematic perspective view of an electromagnetic induction device 6 mounted on the storage tube F. Figure 3 is an external perspective view in which the protective cover 75 is removed from the electromagnetic induction device 6. Figure 4 is a schematic view of the construction of an electromagnetic induction thermistor 14. Figure 5 is a schematic view of the design of the fuse 15. Figure 6 is a sectional view of the fixed state of the electromagnetic induction thermistor 14 and the fuse 15 on the storage tube F. Ig.7 is a sectional view of the structure of the electromagnetic induction heating device 6 mounted on the storage tube F. FIG. 8 is an explanatory view of the state of the magnetic field generated by the winding 68.

An electromagnetic induction heating device 6 is arranged to cover the magnetic tube F2 from the radial outer side, the magnetic tube F2 being a portion for generating heat of the storage tube F, and the magnetic tube F2 generates heat by electromagnetic induction heating. This portion for generating heat of the storage tube F has a two-layer tubular structure with a copper tube F1 on the inside and a magnetic tube F2 on the outside.

The electromagnetic induction heating device 6 comprises a first hex nut 61, a second hex nut 66, a first coil cover 63, a second coil cover 64, a coil main body 65, a first ferrite casing 71, a second ferrite casing 72, a third ferrite casing 73, and a fourth ferrite casing 74 , a first magnetodielectric 98, a second magnetodielectric 99, a winding 68, a protective cover 75, an electromagnetic induction thermistor 14, a fuse 15, and other elements.

The first hex nut 61 and the second hex nut 66 are made of resin and are used to ensure the stability of the fixed state between the electromagnetic induction heating device 6 and the storage tube F using the ring C (not shown). The first coil cover 63 and the second coil cover 64 are made of resin and are used to close the storage tube F from the radial outer side in the upper end position and the lower end position, respectively. The first coil cover 63 and the second coil cover 64 contain four screw holes for screws 69 for securing the first to fourth ferrite housings 71-74, described below, with screws 69. In addition, the second coil cover 64 includes a hole 64f for inserting an electromagnetic induction thermistor for inserting the electromagnetic induction thermistor 14 and fixing it to the outer surface of the magnetic tube F2. The second coil cover 64 comprises a hole 64e for inserting a fuse for inserting a fuse 15 and securing it to the outer surface of the magnetic tube F2. The electromagnetic induction thermistor 14 comprises an electromagnetic induction thermistor sensor 14a, an external protrusion 14b, a side protrusion 14c, and an electromagnetic induction thermistor wire 14d for converting a measurement result of the electromagnetic induction thermistor sensor 14a into a signal and directing it to the control unit 11, as shown in FIG. 4. The electromagnetic induction thermistor sensor 14a has a shape that corresponds to the curved shape of the outer surface of the storage tube F, and has a large contact surface area. The fuse 15 comprises a sensor 15a, an asymmetric shape 15b and fuse wires 15d for converting the measurement result of the fuse sensor 15a into a signal and directing it to the control unit 11, as shown in FIG. 5. Upon receiving a notification from the fuse 15 that the temperature exceeding the predetermined limit temperature has been measured, the control unit 11 controls to cut off the supply of electricity to the winding 68, preventing heat damage to the equipment. The main body 65 of the coil is made of resin, and the winding 68 is wound on the main body 65 of the coil. The coil 68 is wound in a spiral shape on the outside of the coil main body 65, the axial direction being the direction in which the storage tube F. passes. The coil 68 is connected to a control circuit board (not shown) and a high frequency electric current is supplied to the coil. The output signal of the control circuit board is controlled by the control unit 11. The electromagnetic induction thermistor 14 and the fuse 15 are fixed in a state in which the main coil body 65 and the second coil cover 64 are connected together, as shown in FIG. 6. When fixing the electromagnetic induction thermistor 14, a satisfactory state of contact under pressure with the outer surface of the magnetic tube F2 is maintained by pressing radially inward the leaf spring 16 to the magnetic tube F2. Similarly, when the fuse 15 is fixed, a satisfactory contact state under pressure with the outer surface of the magnetic tube F2 is maintained by pressing radially inward the leaf spring 17 to the magnetic tube F2. Thus, since the electromagnetic induction thermistor 14 and the fuse 15 are satisfactorily held in firm contact with the outer surface of the storage tube F, the sensitivity is increased and sudden temperature changes caused by electromagnetic induction heating can be quickly detected. In the first ferrite casing 71, the first coil cover 63 and the second coil cover 64 are held in the direction in which the storage tube F passes and secured in place by screws 69. The first ferrite casing 71 and the fourth ferrite casing 74 accommodate the first magnetodielectric 98 and the second magnetodielectric 99, which are made of highly magnetically permeable material. The first magnetodielectric 98 and the second magnetodielectric 99 absorb the magnetic field created by the winding 68 and form a magnetic flux channel, thereby delaying the leakage of the magnetic field to the outside, as shown in sectional view of the storage tube F and the electromagnetic induction heating device 6 in FIG. 7, as well as in an explanatory view of the magnetic flux in FIG. The protective cover 75 is located around the outer periphery of the electromagnetic induction heating device 6 and collects a magnetic flux that cannot be held only by the first magnetodielectric 98 and the second magnetodielectric 99. The magnetic flux is mainly not scattered on the outer side of the protective cap 75, and the location where the magnetic flux is generated , can be determined arbitrarily.

<1-3> Control of electromagnetic induction heating

The electromagnetic induction heating device 6 described above controls the forced generation of heat by the magnetic tube F2 of the storage tube F during start-up, during which the heating of the air begins when the refrigeration cycle forces the heating of the air while providing the ability to heat the air and during the process defrosting.

The description below, in particular, refers to the start time. Fig.9 is a view showing the features of the transition to various states.

(Initial process during startup)

The initial process during start-up is the process carried out after the heating of the air begins until the pressure measured by the first pressure sensor 29a reaches the target high pressure.

When you enter a command for the process of heating the air in the controller 90 by the user, the control unit 11 starts the process of heating the air. When the heating process begins, the control unit 11 waits until the compressor 21 starts up and the pressure measured by the first pressure sensor 29a reaches a predetermined target high pressure of 39 kg / cm ² (shown by point h in FIG. 9), and causes the internal fan 42 to be driven. This prevents discomfort for the user due to unheated air passing into the room at a stage in which the refrigerant passing through the internal heat exchanger 41 has not yet been heated.

Electromagnetic induction heating using an electromagnetic induction heating device 6 is carried out here, while the degree of opening of the external electric expansion valve 24 is maintained at a fixed degree of opening to shorten the time interval for starting the compressor 21 and reaching the pressure measured by the first pressure sensor 29a, 39 kg / cm ² . The control unit 11 starts the process of rapidly increasing pressure after confirming that a sufficient flow of refrigerant is provided in the storage tube F after starting compressor 21. During the process of rapidly increasing pressure to reduce the time required to reach the temperature measured by the electromagnetic induction thermistor 14, the target temperature is 80 ° C the storage tube at startup, the control unit 11 starts supplying electric current to the coil 68 of the electromagnetic induction heating device 6 when the maximum power supplied (2 kW). This output state of the electromagnetic induction heating device 6 at a given maximum supplied electric power continues until the temperature measured by the electromagnetic induction thermistor 14 reaches the target temperature of 80 ° C of the storage tube at startup.

Thus, the control is carried out to maintain the degree of opening of the external electric expansion valve 24 at a fixed degree of opening to reduce the time required to achieve a given target high pressure at startup or to bring the output signal of the electromagnetic induction heating device 6 to the maximum supplied electric power to reduce the time required to achieve the temperature measured by the electromagnetic induction thermistor 14, to temperature of the storage tube at start-up, but there is a danger that this induction heating causes an excessive increase in the degree of overheating of the refrigerant sucked into the compressor 21. Therefore, to prevent such excessive increases in the degree of overheating of the sucked-in refrigerant, overheating protection at start-up is controlled (described below) control unit 11 at startup.

(Helper process during startup)

The auxiliary process during start-up is the process during start-up, which is carried out after the pressure measured by the first pressure sensor 29a reaches the target high pressure.

In the auxiliary process during start-up, after the pressure measured by the first pressure sensor 29a has reached the target high pressure of 39 kg / cm ² , a steady output process is carried out to increase the amount of refrigerant to circulate in the refrigeration cycle and increase productivity by increasing the compressor rotation speed 21 and increasing the degree of opening of the external electrical expansion valve 24.

After the start of the process of heating the air and when the target temperature of the storage tube is reached at 80 ° C start-up and the initial action is completed at start-up, the control unit 11 maintains the output signal at a stably supplied electric power (1.4 kW), which is less than the set maximum supplied electric power (2 kW) , and controls the output signal of the electromagnetic induction heating device 6, so that the temperature measured by the electromagnetic induction thermistor 14 is maintained at a temperature close to Coy to the target temperature of 80 ° C, the same as the target temperature at start accumulative tube. With this control, maintaining a temperature close to 80 ° C, the control unit 11 carries out a process in which induction heating using an electromagnetic induction heating device 6 begins with a stably supplied electric power (1.4 kW) at the output when the temperature measured by an electromagnetic induction thermistor 14 is equal to or less than 60 ° C, and the induction heating by the electromagnetic induction heating device 6 is stopped when the temperature measured by the electromagnetic ind ktsionnym thermistor 14, reaches 80 ° C.

(Regular process after completion of the process during startup)

Due to the continued stable output control, increased rotation speed of the compressor 21, increased degree of opening of the external electric expansion valve 24, and increased amount of refrigerant for circulation in the refrigeration cycle, the process during startup is completed when the amount for circulation corresponding to the operating state is reached, and then regular process. In this regular process, the setting of the degree of subcooling is controlled, as a result of which the control unit 11 controls the degree of opening of the external electric expansion valve 24, so that the degree of subcooling of the refrigerant passing through the outlet side of the internal heat exchanger 41 in the circuit during the air heating process is kept constant at a given value . This degree of subcooling is obtained using the control unit 11, which calculates the difference between the saturation temperature corresponding to the pressure measured by the second pressure sensor 29g and the temperature measured by the internal heat transfer temperature sensor 44.

(Management of protection against overheating at startup)

The control of overheating protection at start-up is control to provide an increase in the degree of opening of the external electric expansion valve 24 in order to prevent an excessive increase in the degree of overheating of the refrigerant sucked into the compressor 21 due to induction heating using an electromagnetic induction heating device 6 at the initial maximum supplied electric power (2 kW) during startup.

10 is a flowchart of a control of protection against overheating at startup.

In step S11, the control unit 11 confirms that the temperature measured by the electromagnetic induction thermistor 14 has decreased after the start of the compressor 21 has started (shown by point a in FIG. 9), and then proceeds to step S12.

In step S12, the control unit 11 switches the output signal of the electromagnetic induction heating device 6 from state 0 to the maximum supplied electric energy (2 kW) (shown in FIG. 9 as a change from point b to point c) and at the same time starts to use the time using timer 95 .

In step S13, the control unit 11 determines whether or not the temperature measured by the electromagnetic induction thermistor 14 has reached the target temperature of the storage tube at 80 ° C at startup. When the target temperature of the storage tube is reached at startup of 80 ° C (shown as point d in FIG. 9), the process proceeds to step S14.

In step S14, the control unit 11 temporarily stops the induction heating by means of the electromagnetic induction heating device 6 (shown as point e in FIG. 9) and ends the countdown of the timer 95 started in step S12.

In step S15, the control unit 11 determines whether or not the rotation speed measured by the node 29r is greater to determine the rotation speed, the estimated rotation speed to minimize overheating of 82 rpm (82 rpm). This estimated rotational speed to minimize overheating is the rotational speed set in advance as the rotational speed at which the degree of superheat of the refrigerant sucked into the compressor 21 is unlikely to increase excessively based on the conditions set for the refrigeration cycle. Since the inlet pressure is unlikely to decrease much when this estimated rotation speed is not fulfilled to minimize overheating, it has been found that there is a danger of an excessive increase in the degree of overheating of the refrigerant sucked into the compressor 21, and the overheating protection control at startup is completed. If the estimated rotation speed is exceeded to minimize overheating, the process proceeds to step S16.

In step S16, the control unit 11 determines whether or not the value of the timer 95 at the end of the count in step S14 is less than the time of estimating the rate of temperature increase of 20 seconds. This time for estimating the rate of increase in temperature is the time interval set in advance as the time interval corresponding to the rate of increase in temperature at which the degree of overheating of the refrigerant sucked into the compressor 21 is unlikely to increase excessively based on the conditions set for the refrigeration cycle. Specifically, when the time required to reach the target temperature of the storage tube when starting 80 ° C after the start of induction heating using the electromagnetic induction heating device 6 is less than the time (20 seconds) for estimating the rate of increase in temperature, the rate of increase in temperature measured by the electromagnetic induction thermistor 14, is too large, and proceeds to step S17, and the protection procedure is carried out on the basis that there is a danger of excessive step increase audio superheat of the refrigerant sucked into the compressor 21. In contrast, when the necessary time reaches or exceeds the time of the rate of temperature increase, it is found that there is a danger of an excessive increase in the degree of superheat of the refrigerant sucked into the compressor 21, and completes control overheating protection upon startup.

In step S17, the control unit 11 carries out a process of increasing the degree of opening of the valve to increase the degree of opening of the external electric expansion valve 24 to increase the amount of refrigerant to circulate through the storage tube F, thereby preventing the temperature in the storage tube F from growing too quickly due to induction heating by electromagnetic induction heating device 6. In this process of increasing the degree of opening of the valve, the degree of opening of the external electron Cesky expansion valve 24 is increased by 20 pulses every 20 seconds. This process of increasing by 20 pulses every 20 seconds is repeated until the rate of temperature increase measured by the electromagnetic induction thermistor 14 due to induction heating is equal to or less than the set speed. Specifically, simultaneously with the action of increasing the degree of opening of the external electric expansion valve 24, it is carrying out a process for determining whether or not the rate of increase in the temperature measured by the electromagnetic induction thermistor 14 has ceased to exceed a predetermined speed, and when the degree of opening of the external electric expansion valve 24 has increased to a point greater not exceeding a predetermined speed, it is determined that there is no longer a danger of an excessively large increase in storage temperature tube F, and the process of increasing the valve opening degree is completed.

The control of overheating protection at startup is completed by the aforementioned method.

After the pressure measured by the first pressure sensor 29a has reached the target high pressure, stable output control is performed as described above, as a result of which the frequency of the compressor 21 increases, the degree of opening of the external electric expansion valve 24 is further increased, the amount of refrigerant circulating in the refrigeration cycle , increases further and the refrigeration cycle productivity rises.

(Regular control of overheating protection)

Regular control of the overheat protection is control to prevent an excessive increase in the degree of overheating due to induction heating when the opening degree of the external electric expansion valve 24 is increased, a temporary decrease in the temperature measured by the electromagnetic induction thermistor 14 is determined, and the induction heating is carried out using an electromagnetic induction heating device 6, when the degree of subcooling is controlled Niya.

11 is a flowchart of regular control of overheating protection.

In step S21, when the temperature measured by the electromagnetic induction thermistor 14 is 80 ° C or less, the control unit 11 increases the output of the electromagnetic induction heating device 6 from state 0 to the output signal (stable level) due to the steady supply of electricity (1.4 kW; steady level).

In step S22, the control unit 11 determines whether or not the temperature measured by the electromagnetic induction thermistor 14, 80 ° C, has reached. If it reaches 80 ° C, the process proceeds to step S23.

In step S23, the control unit 11 temporarily stops the induction heating by the electromagnetic induction heating device 6.

In step S24, after the induction heating is stopped by the electromagnetic induction heating device 6, the control unit 11 continues to determine a method in which the temperature measured by the electromagnetic induction thermistor 14 increases and determines whether or not the temperature is excessively elevated at 110 ° C. Specifically, the control unit determines whether or not an excessive rise occurs at which the temperature measured by the electromagnetic induction thermistor 14 continues to rise above 80 ° C regardless of the completion of the induction heating by the electromagnetic induction heating device 6. The temperature is excessively high, 110 ° C set in advance on the basis of the calculated conditions of the refrigeration cycle, as the temperature at which, after exceeding its value, the degree of overheating x adagenta sucked into the compressor 21 rises excessively. If it is determined that the excessively high temperature has been exceeded, the process proceeds to step S25. If it is determined that the excessively elevated temperature has not been exceeded, it is determined that there is no danger of excessively increasing the degree of overheating of the refrigerant sucked into the compressor 21, and the overheating protection control at startup is completed.

In step S25, the control unit 11 makes adjustments to increase the degree of opening (the process of adjusting the degree of opening of the valve), in which the degree of opening of the external electrical expansion valve 24, controlled by controlling the setting of the degree of subcooling, increases by another 50 pulses from its value. Here the increase is equal to 50 pulses, which is more than a single increase of 20 pulses in the degree of opening of the external electric expansion valve 24 when controlling the overheating protection at startup described above. Thus, it is possible to quickly prevent an excessive increase in temperature in the collection tube F, even when it turns out that an abnormal condition will occur when the overheating protection is regularly controlled.

Regular control of overheating protection is completed by the aforementioned method.

With regular control of the overheat protection, since the rotation speed at which the compressor 21 is driven already exceeds 82 rpm, the determination of the control of the overheat protection at startup is unnecessary.

<Characteristics of the air conditioning 1 of the present embodiment>

(one)

When induction heating using an electromagnetic induction heating device 6, the temperature increases rapidly not in the refrigerant passing through the sections in the refrigeration cycle located at a certain distance from the compressor 21, but in the refrigerant passing through the storage tube F immediately before being sucked into the compressor 21. The refrigerant, passing through the inlet side of compressor 21 is either very dry or superheated, and this refrigerant is more likely to have a change in physical heat lots or an increase in temperature compared with cases of changes in latent heat in a gas-liquid biphasic refrigerant passing further upstream. Since the refrigerant sucked into the compressor 21 is heated, the heat generated in the magnetic tube F2 is affected by heat transfer or the like, and therefore it is difficult to determine the temperature of the refrigerant actually sucked into the compressor 21.

When controlled by the air conditioner 1 of the present embodiment in such a situation, this is not the temperature of the refrigerant actually sucked into the compressor 21, which is determined by the electromagnetic induction thermistor 14, but rather the temperature of the magnetic tube F2 of the storage tube F, in which heat is generated by induction heating . Based on the temperature measured by the electromagnetic induction thermistor 14, the opening degree of the external electric expansion valve 24 can be increased and the amount of refrigerant supplied to the inlet side of the compressor 21 can increase, so that there is no excessive increase in the degree of overheating of the refrigerant sucked into the compressor 21. Thus Thus, in cases of heating of the refrigerant on the inlet side of the compressor 21, the amount of heat applied to the sucked-in refrigerant can be calculated using temperatures Measured electromagnetic induction thermistor 14 and minimize any excessive increase in the degree of superheat of the refrigerant sucked into the compressor 21, even in cases in which it is difficult to determine the actual temperature of the sucked refrigerant.

(2)

By controlling the overheating protection at startup of the present embodiment, in situations in which the temperature of the magnetic tube F2 of the storage tube F suddenly rises due to induction heating during startup, it is possible to minimize excessive increases in the degree of overheating of the refrigerant sucked into the compressor 21 by increasing the degree of opening of the external electric expansion valve 24 and supplying more refrigerant. This start-up overheating protection control takes into account the rotation speed at which the compressor 21 is driven and increases the degree of opening of the external electrical expansion valve 24 only when the temperature of the magnetic tube F2 suddenly rises even under circumstances in which the actuation state of the compressor 21 is ensured. by selecting a preset estimated rotational speed to minimize overheating as the rotational speed at which normally does not occur measured increase in temperature. Therefore, increases in the degree of opening of the external electrical expansion valve 24 can be prevented during startup at a stage where the rotational speed at which the compressor 21 is driven has not yet increased much. Thus, it is unlikely that there will be a difference between the high and lower pressures due to a larger increase than is necessary with the degree of opening of the external electrical expansion valve 24, and it is possible to prevent the increase in the time interval necessary for the pressure measured by the first pressure sensor 29a to reach a predetermined target high pressure 39 kg / cm ² and also to provide high-temperature refrigerant to the internal heat exchanger 41.

The point in time at which the opening degree of the external electrical expansion valve 24 increases when controlling the overheating protection at start-up does not have a control point for determining whether or not the temperature measured by the electromagnetic induction thermistor 14 has exceeded a specific temperature, and instead uses the rate of temperature increase as control point. Therefore, it is not necessary to set another new evaluation temperature that is higher than the target storage tube temperature at startup, or to determine whether or not this evaluation temperature has been exceeded. Moreover, when it was determined that a certain rate of temperature increase was exceeded than when it was determined that the evaluation temperature was exceeded, because the subsequent temperature of the storage tube F increases faster. Therefore, the reliability of the device can be improved in the aforementioned embodiment, in which cases in which such excessive temperature increases often occur can be determined.

For example, given the case in which control is performed to increase the degree of opening of the external electrical expansion valve 24 when the evaluation temperature has been exceeded, with 90 ° C being set as the temperature above the target temperature of the storage tube at startup, it takes several minutes for the temperature measured electromagnetic induction thermistor 14, increased from 89 ° C to exceed 90 ° C, and the degree of opening of the external electrical expansion valve 24 increases, even when Neno, after that the temperature will not increase by more than a few degrees, even with the passage of time. In contrast, when controlling the overheating protection when starting the aforementioned embodiment, the opening degree of the external electric expansion valve 24 increases only when the temperature increasing rate is determined at which 80 ° C are exceeded after 20 seconds, and therefore, it is possible to prevent a decrease in the refrigerant outlet temperature, caused by an unnecessary increase in the degree of opening of the external electrical expansion valve 24.

(3)

In addition, with regular control of the overheating protection, when the temperature measured by the electromagnetic induction thermistor 14 has exceeded an excessively elevated temperature of 110 ° C due to the induction heating carried out while controlling the setting of the degree of subcooling, the opening degree is further increased relative to the degree of opening of the external electric expansion valve 24 controlled by controlling the setting of the degree of subcooling. Therefore, compared with the control in which only the degree of opening is controlled to a certain extent, when an excessively elevated temperature of 110 ° C is exceeded, the amount of refrigerant passing through the storage tube F can reliably increase and, therefore, any excessive increase in the degree of overheating of the refrigerant sucked in into compressor 21, can be minimized more reliably.

This regular control of the overheating protection is carried out in a state in which the amount of refrigerant for circulation in the refrigeration cycle is more constant than during start-up and sudden increases in temperature of the storage tube F are unlikely, therefore, no determination is necessary based on the rate of increase in temperature, and reliability can be provided in sufficient quantities by using a simple determination method to determine whether or not excessively elevated temperatures have been exceeded 110 ° C.

Thus, it is also possible to increase the time interval during which heat is supplied to the magnetic tube F2 due to induction heating by means of an electromagnetic induction heating device 6, since the amount of refrigerant sucked into the compressor 21 increases.

Until the electromagnetic induction thermistor 14 measures an excessively elevated temperature of 110 ° C, which is a higher temperature than 80 ° C, at which the induction heating is stopped by the electromagnetic induction heating device 6, the degree of opening of the external electric expansion valve 24 is maintained at the degree of opening during the control of the installation, the degree of subcooling, and the degree of opening of the external electrical expansion valve 24 does not increase, trace Therefore, the time interval during which the high temperature of the refrigerant can be maintained by induction heating can be further increased.

<Other Embodiments>

An embodiment of the present invention has been described above based on the drawings, but the specific configuration is not limited to this embodiment, and modifications are possible within a range that does not deviate from the scope of the present invention.

(A)

In the embodiment described above, an example of a case has been described in which 430 stainless steel is used as the material of the magnetic tube F2.

However, the present invention is not limited to this example. The magnetic tube can be made, for example, of iron, copper, aluminum, chromium, nickel, other conductors and alloys containing at least two or more metals selected from this list.

An example of the magnetic material presented here contains, for example, ferrite, martensite, or a combination of these two materials, but it is preferable to use a ferromagnetic material that has a relatively high electrical resistance and which has a higher Curie temperature than its temperature range of use.

The storage tube F here requires more electricity, but it optionally contains a magnetic substance and a material containing a magnetic substance, or it may include a material that will be a target for induction heating.

The magnetic material can, for example, constitute the entire storage tube F, can only be formed on the inner surface of the storage tube F, or can only be present due to inclusion in the material constituting, for example, the storage tube F.

(B)

In the embodiment described above, an example of a case has been described in which the condition for increasing the degree of opening of the external electric expansion valve 24 differs between overheating protection control at startup and regular overheating protection control.

However, the present invention is not limited to this example. The condition for increasing the degree of opening of the external electrical expansion valve 24 may, for example, be the same for controlling overheating protection at startup, and regularly controlling overheating protection.

(C)

In the embodiment described above, an example of a case has been described in which control is performed to maintain the degree of subcooling set after completion of control during startup.

However, the present invention is not limited to this example. For example, control can be performed to maintain the degree of change in the state of distribution of the refrigerant in the refrigeration cycle for a given time interval or for a given distribution state or within a given distribution range. To determine this state of distribution of the refrigerant, the state of distribution of the refrigerant can be determined by providing a sight glass in the condenser of the refrigeration cycle or using another method to determine the liquid surface of the refrigerant, and stability control can be performed so that the distribution state reaches a predetermined distribution state or is within a predetermined distribution state distribution range.

(D)

In the embodiment described above, an example of a case has been described in which, in the refrigerant circuit 10, the electromagnetic induction heating device 6 is fixed to the storage tube F.

However, the present invention is not limited to this example.

For example, the electromagnetic induction heating device 6 may be mounted on a refrigerant pipe other than the storage tube F. In this case, the magnetic tube F2 or another magnetic element is located on the portion of the refrigerant pipe where the electromagnetic induction heating device 6 is fixed.

(E)

In the embodiment described above, a case has been described in which the storage tube F is made in the form of a two-layer tube comprising a copper tube F1 and a magnetic tube F2.

However, the present invention is not limited to this example.

The magnetic element F2a and two stops F1a, F1b may be located inside the storage tube F and the refrigerant tube as a heated object, for example, as shown in FIG. The magnetic element F2a is an element containing magnetic material, whereby heat is generated due to electromagnetic induction heating in the embodiment described above. The limiters F1a, F1b are located at two locations inside the copper tube F1, usually allowing the passage of refrigerant, but not allowing the passage of the magnetic element F2a. Thus, the magnetic element F2a does not move despite the flow of refrigerant. Therefore, the predetermined heating position in the collecting tube F, for example, can be heated. In addition, since the magnetic element F2a for generating heat and the refrigerant are in direct contact, the heat transfer efficiency can be improved.

(F)

The magnetic element F2a described in another embodiment (L) may be located in the tube without the use of stops F1a, F1b.

As shown in FIG. 13, for example, curved portions FW may be formed at two locations in a copper tube F1, and a magnetic element F2a may be located inside the copper tube F1 between curved portions FW formed at two locations. The movement of the magnetic element F2a in this way can also be limited while allowing the passage of refrigerant.

(G)

In the embodiment described above, an example of a case has been described in which a winding 68 has been wound around a storage tube F in a spiral shape.

However, the present invention is not limited to this example.

For example, a coil 168 wound around a coil main body 165 may be located around the periphery of the storage tube F without being wound around the storage tube F, as shown in FIG. The main body 165 of the coil is arranged so that its axial direction is essentially perpendicular to the axial direction of the storage tube F. The two main body 165 of the coil and winding 168 are located separately in order to center the storage tube F.

In this case, the first coil cover 163 and the second coil cover 164, which pass through the collection tube F, can be located in the installation state above the main body 165, as shown, for example, in FIG.

In addition, the first coil cover 163 and the second coil cover 164 can be fixed in place by midway between the first ferrite casing 171 and the second ferrite casing 172, as shown in FIG. 16. FIG. 16 shows an example of a case in which two ferrite shells are arranged in order to center the storage tube F, but they can be arranged in four directions, similar to the embodiment described above. The magnetodielectric may also be placed, similar to the embodiment described above.

(H)

In the embodiment described above, an example of a case in which the rate of temperature increase is large or not is described is determined by reference to whether or not a time interval shorter than the time (20 seconds) of estimating the rate of temperature increase is necessary to reach the target temperature 80 ° C of the storage tube when starting after the start of induction heating using an electromagnetic induction heating device 6.

However, the method for determining the rate of temperature increase is not limited to this determination method.

For example, instead of actually determining the rate of temperature increase, the information table may be stored in advance in the controller 90, and the control unit 11 may perform control, such as estimating the rate of temperature increase by referring to this information table, and then increase the degree of opening of the external electrical expansion valve 24.

An example of such an information table is data that correlates the current temperature measured by the electromagnetic induction thermistor 14, the degree to which the storage tube F is heated by the electromagnetic induction heating device 6, the amount of refrigerant for circulation passing through the storage tube F, the density of the refrigerant passing through storage tube F, outdoor temperature and other parameters, as well as values calculated in advance as temperature variations corresponding to these parameters. When the temperature increasing rates are calculated in advance in this way, they are preferably calculated based on the thermal conductivity of the magnetic tube F2 and the copper tube F1, the thermal conductivity between the magnetic tube F2 and the copper tube F1, the thermal conductivity between the copper tube F1 and the refrigerant, and other factors.

The extent to which the storage tube F is heated by the electromagnetic induction heating device 6 can be converted from the amount of electricity supplied by the electric current supply unit 21e, which is measured by the compressor electricity sensor 29f. The amount of refrigerant for circulation passing through the accumulating tube F, or the density of the refrigerant passing through the accumulating tube F, can be converted from the rotational speed of the piston of the compressor 21, which is determined by the node 29r to determine the rotation speed, high pressure detected by the first pressure sensor 29a, low pressure detected by the second pressure sensor, or the like. The outdoor temperature can be determined as the temperature measured by the outdoor temperature sensor 29b. By preliminary storing the information table in the controller 90 in this way, the processing load of the control unit 11 can be reduced.

Instead of storing such an information table in the controller 90, the predetermined relationship equation can be stored in the controller 90, and the control unit 11 can calculate the estimated temperature increase rates based on the values determined by the sensors described above.

The information table and calculation can be simplified by first determining the amount of electricity supplied to the electromagnetic induction heating device 6 using the electric current supply unit 21e in two forms consisting of a given output signal (e.g., 2 kW) and another predetermined output signal (e.g. 1.4 kW), based on, for example, the outdoor temperature.

Thus, when the control unit 11 does not actually determine the rate of increase in temperature, but instead determines it by calculating from the information table or the given relationship equation or using another method, the time interval for the actual measurement of the rate of increase in temperature is not needed and, therefore, can faster process to be implemented.

(I)

In the embodiment described above, an example of a case has been described in which, during the stable output control after the start of start, a process is carried out in which the induction heating by the electromagnetic induction heating device 6 starts when the output of the stably supplied electric power (1.4 kW) is when the temperature measured by the electromagnetic induction thermistor 14 is 60 ° C or less, and the induction heating by the electromagnetic induction heating device 6 is terminated when the temperature measured by the electromagnetic induction thermistor 14, reaches 80 ° C, so that the temperature measured by the electromagnetic induction thermistor 14, supported close to the target temperature of 80 ° C accumulative tube at startup.

However, the control for maintaining the temperature measured by the electromagnetic induction thermistor 14 close to 80 ° C during a stable output control is not limited to such control.

For example, the control unit 11 can maintain the temperature measured by the electromagnetic induction thermistor 14 close to 80 ° C due to the proportional-integral control of the frequency of supply of electric current to the electromagnetic induction heating device 6 based on the temperature measured by the electromagnetic induction thermistor 14. integral regulation, in which one installation is the supply of electric current to an electromagnetic induction heating device 6 with a continuously fixed output signal of stably supplied electric energy (1.4 kW) for 30 seconds, the control unit 11 can adjust the frequency at which this setting is repeated, based on the time taken from the end of the most recent supply of electric current to the electromagnetic induction heating device 6 until the temperature measured by the electromagnetic induction thermistor 14 drops again below 80 ° C. Specifically, control can be carried out in such a way that the longer this time is used, the higher the frequency at which the above setting is repeated.

<Other>

Embodiments of the present invention have been described above in several examples, but the present invention is not limited to these embodiments. For example, the present invention also includes combined embodiments obtained by a suitable combination of various parts of the above embodiments within a range that can be made based on descriptions by those skilled in the art.

Industrial applicability

According to the present invention, even when the refrigerant on the inlet side of the compression mechanism is heated, it is possible to carry out a control that takes into account the amount of heat applied to the sucked-in refrigerant while controlling the degree of overheating of the refrigerant sucked into the compression mechanism, and therefore the present invention is especially used in An air conditioner that heats the refrigerant by induction heating.

List of Reference Items

1 - air conditioning

11 - control unit (unit for determining the state of the refrigerant on the side of the cooling device)

14 - electromagnetic induction thermistor (temperature sensor of released heat)

21 - compressor (compression mechanism)

23 - external heat exchanger (device for heating the refrigerant)

24 - external electrical expansion valve (expansion mechanism)

29a is the first pressure sensor (unit for determining the state of the refrigerant on the side of the cooling device)

29g - second pressure sensor

41 - internal heat exchanger (device for cooling the refrigerant)

44 - internal heat transfer temperature sensor (unit for determining the state of the refrigerant on the side of the cooling device)

68 - winding (magnetic field generator)

F - storage tube (refrigerant pipe, inlet refrigerant pipe)

List of patent literature

<Patent Literature 1> Published Japanese Patent Laid-Open No. 7-120083.

Claims (6)

1. Air conditioning (1), which includes at least a compression mechanism (21), a device (41) for cooling the refrigerant, an expansion mechanism (24) and a device (23) for heating the refrigerant, the conditioner (1) comprising :
a magnetic field generator (68) for generating a magnetic field for induction heating of the refrigerant pipe (F) for circulating the refrigerant into the compression mechanism (21), a device (41) for cooling the refrigerant, an expansion mechanism (24) and a device (23) for heating the refrigerant and / or an element in thermal contact with the refrigerant passing through the refrigerant pipe (F);
a sensor (14) for the temperature of the released heat to measure the temperature of the portion that generates heat by induction heating using a magnetic field generator (68); and a control unit (11) for controlling overheating protection to increase the degree of opening of the expansion mechanism (24), or when the temperature measured by the temperature sensor (14) of the generated heat reaches or exceeds a predetermined temperature of the generated heat, or when the rate of increase of the temperature measured the sensor (14) of the temperature of the released heat reaches or exceeds a predetermined rate of increase. 2. The air conditioner (1) according to claim 1, in which the magnetic field generator (68) generates a magnetic field for induction heating of the refrigerant pipe (F) in the inlet inside the refrigerant pipe on the inlet side of the compression mechanism (21) and / or element thermal contact with the refrigerant passing through the inlet refrigerant pipe (F). 3. The air conditioner (1) according to claim 1, in which the control unit (11) controls at start-up to force the magnetic field to be generated by the magnetic field generator (68), so that the temperature of the area where the heat is generated by induction heating using the generator ( 68) of the magnetic field, reaches a predetermined target temperature at startup, while the actuation of the compression mechanism (21) starts from the off state of the compression mechanism (21), and also controls after starting after completion at board at startup; and
when controlling overheating protection, control is also performed after start-up, the control unit (11) increases the degree of opening of the expansion mechanism (24) when the temperature measured by the temperature sensor (14) of the generated heat reaches or exceeds the set temperature of the released heat after start-up, which is a temperature equal to or greater than the specified target temperature at startup. 4. The air conditioner (1) according to claim 3, in which when controlling the overheating protection, control at the same time is carried out at startup, the control unit (11) increases the degree of opening of the expansion mechanism (24) when the rate of temperature increase measured by the temperature sensor (14) heat released at the moment when the specified target temperature at startup is reached, reaches or exceeds the specified increase rate. 5. The air conditioner (1) according to claim 4, wherein, when determining a predetermined increase rate that has been reached or exceeded, the control unit (11) increases the degree of opening of the expansion mechanism (24) only when the rotation speed of the compression mechanism (21) reaches or exceeds the set rotation speed. 6. Air conditioning (1) according to any one of claims 3 to 5, further comprising a unit (44, 29a, 11) for determining the state of the refrigerant on the side of the cooling device for determining the state of the refrigerant passing from the device (41) for cooling the refrigerant into an expansion mechanism (24);
at the same time, upon completion of control at startup, the control unit (11) starts controlling the setting of the degree of subcooling to control the degree of opening of the expansion mechanism (24), so that the degree of subcooling, determined using the value determined by the unit (44, 29a, 11) to determine the state of the refrigerant on the side of the cooling device, remains unchanged at a given target degree of subcooling; and
when controlling overheating protection, it is also possible to control the setting of the degree of subcooling, the control unit (11) additionally increases the degree of opening of the expansion mechanism (24) beyond the limits of the degree of opening regulated by controlling the setting of the degree of subcooling when the temperature measured by the temperature sensor (14) stands out heat, reaches or exceeds the set temperature of the released heat when controlling the installation of the degree of subcooling, which is the temperature Q, equal to or greater than the predetermined target temperature when running.

Images