FR2888919A1 - Heat cycle system for vehicle, has control device executing three operating modes controlling degree of opening of valve, so that exchanger evacuates coolant heat towards exterior air or coolant evacuates heat towards air - Google Patents

Abstract

The system has a control device executing three operating modes. One of the modes controls a degree of opening of a pressure reduction valve (113), so that temperature of a coolant discharged from a compressor (111) is equal to the temperature of hot water in a water-coolant heat exchanger (112) and the exchanger evacuates the coolant heat towards exterior air. Another mode controls the degree of opening to reduce the coolant pressure, so that the coolant temperature is less than that of the hot water and the coolant absorbs heat from the water and evacuates the heat towards the air. The third operating mode of the control device is used for controlling a degree of opening of the pressure reduction valve to a preset level for leading the heat exchanger to evacuate heat from the coolant towards hot water. Independent claims are also included for the following: (1) a device for controlling a heat cycle system (2) a method for controlling a heat cycle system.

Description

HEAT CYCLE SYSTEM AND CONTROL DEVICE AND SOUND

CONTROL METHOD

  BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat cycle system suitable for use in bringing the heat of a heat pump cycle, for example, to water. hot to adjust the temperature of a vehicle engine and use it as a heat source for heating purposes and a control device and its control method. 2. Description of the Related Art In the related art, as an air conditioning system for a vehicle, there is known a vehicle heat pump type air-conditioning system, as shown in the Japanese patent. N 3 105 707. In this air conditioning system, a four-way valve arranged in the heat pump cycle is used to tilt the flow direction of a refrigerant for selective use. an indoor heat exchanger as a heat sink or as a heat sink, and thereby to allow the cooling and heating needs to be managed.

  In addition, when defrosting an outdoor heat exchanger during heating, if the vehicle's travel falls below a predetermined speed or if the vehicle is stationary or if the outdoor heat exchanger falls below a predetermined flow rate, a defrosting operation is performed to reverse the flow direction of the refrigerant to cause the outdoor heat exchanger to operate as a heat sink and the indoor heat exchanger to function as a heat absorber. This allows efficient defrosting.

  However, in the related art, defrosting (switching from heating operation to defrosting operation) requires the use of the four-way valve to tilt the refrigerant flow direction. Failover takes time. There is consequently the problem that if the time for the speed of movement, stopping state, input flow, or other conditions are satisfied is short, sufficient defrosting is not possible. . In particular, for example, if we assume a defrost when the vehicle is stopped (when waiting for a traffic light to change during normal driving), even if we switch the pump cycle In the heat operation of the heating operation in the defrosting operation, the shutdown state often ends before the cycle is stabilized, so that sufficient defrosting is not possible.

  SUMMARY OF THE INVENTION It is therefore an object of the present invention, in view of the foregoing problem, to provide a heat cycle system capable of instantaneously switching to a defrosting operation when defrosting is required during operation. heater and a control device and its control method.

  To achieve the above object, the present invention employs the following technical means: According to a first aspect of the present invention, there is provided a heat cycle system having a compressor (111) discharging compressed refrigerant at a high temperature. and a high pressure, a heat exchanger (112) exchanging heat between the refrigerant discharged from the compressor (111) and the hot water used to adjust the temperature of a heat emitting device (10) and used as a heat source of a heater (122), a pressure reducing valve (113) whose degree of opening can be varied and reducing the pressure of the refrigerant discharged from the water-coolant heat exchanger ( 112), an external heat exchanger (114) exchanging heat between the refrigerant exiting the pressure reducing valve (113) and the outside air and returning refrigerant to the side of the compressor (111) and a controller (130) for executing one of a first mode of operation controlling the degree of opening to a predetermined degree of opening to bring the water-coolant heat exchanger (112) for discharging heat from the coolant to the hot water, a second operating mode controlling the degree of opening so that the temperature of the refrigerant discharged from the compressor (111) becomes substantially equal to a temperature of the hot water at the water-coolant heat exchanger (112) to cause the outdoor heat exchanger (114) to exhaust heat from the coolant to the outside air , and a third mode of operation making the degree of opening greater than in the second mode of operation so as to reduce the pressure of the refrigerant discharged from the compressor (111) to make the temperature of the r coolant lower than the temperature of the hot water and thereby causing the water-coolant heat exchanger (112) to cause the refrigerant to absorb heat from the hot water and to cause the External heat exchanger (114) causes the refrigerant to exhaust heat to the outside air.

  Therefore, through the execution of the first mode of operation, it becomes possible to heat the hot water to make the heating at the heater t.1i (122) possible or to increase the capacity of heating. In this heating operation, the low temperature outside air can cause icing of the outdoor heat exchanger (114). Accordingly, by executing the second mode of operation for the execution of the first mode of operation, the heat of the compression work at the compressor (111) can then be exhausted to the outside air at the heat exchanger outside (114) without affecting the temperature of the hot water, so the heating of the outside air side becomes possible. That is, icing at the outdoor heat exchanger (114) can be prevented from an early stage. In addition, by performing the third mode of operation, the heat of the compressing work at the compressor (111) and the heat absorbed from the hot water can be discharged to the outside air at the heat exchanger. external heat (114), so that the amount of heat removed can be increased and the outdoor heat exchanger (114) can be defrosted. Further, the switchover to the second mode of operation and the third mode of operation can be managed simply by varying the degree of opening of the pressure reducing valve (113) to the larger side without changing the direction of flow. refrigerant, so that instant defrost becomes possible.

  Preferably, the controller (130) makes the opening degree fully open when performing the third mode of operation.

  As a result, the pressure on the high pressure side forming the discharge side of the compressor (111) can be reduced to the maximum extent and the amount of heat absorbed from the hot water can be increased, so it becomes possible to increasing the amount of heat evacuated at the outdoor heat exchanger (114), and further improving the defrosting effect.

  More preferably, the controller (130) maximizes an unloading amount of the compressor (111) when performing the third mode of operation.

  As a result, it is possible to increase the amount of heat removed at the outdoor heat exchanger (114) so that the defrost effect can be further increased.

  More preferably, the controller (130) switches from the first mode of operation to the second mode of operation or the third mode of operation and switches from the second mode of operation to the third mode of operation by varying the degree of opening in the direction of opening while implementing the compressor (111).

  As a result, it is possible to switch to the second operating mode or the third operating mode without the time required to stop and restart the compressor (111) and the time until the cycle pressure stabilizes, so that defrosting can be performed in a short time (instantly).

  More preferably, the system is mounted on a vehicle and the controller (130) executes the second mode of operation when the flow of outside air entering the outdoor heat exchanger (114) or a correlated physical quantity. the flow rate exceeds a first predetermined value or if the vehicle is in motion.

  As a result, when the flow of outside air entering the outdoor heat exchanger (114) or a physical quantity correlated to this flow exceeds a first predetermined value, the conditions become more conductive for the cooling of the heat exchanger. external heat (114) by the outside air. Accordingly, in this case, the second mode of operation, which does not affect the temperature of the hot water, is preferably performed.

  More preferably, the system is mounted on a vehicle and the controller (130) executes the third mode of operation when a flow of outside air entering the outdoor heat exchanger (114) or a physical quantity correlated to the flow rate is a second predetermined value or less or when the vehicle is stationary.

  Therefore, if the flow rate of the outside air entering the outdoor heat exchanger (114), or a physical quantity correlated to this flow rate, is a second predetermined value or less, the conditions preclude the cooling of the external heat exchanger (114) by the outside air, also defrosting by the third mode of operation is preferably performed.

  More preferably, the first predetermined value is set to a value of the second or more predetermined value. As a result, no contraction appears in the command.

  More preferably, the system is mounted on a vehicle and the controller (130) stops the operation of the compressor (111) when the vehicle traveling speed is a predetermined speed or more.

  As a result, since, when the vehicle speed is high, the hot water temperature is increased by the heat emitted from the engine (10) itself and the heating capacity of the heater (122) is ensured. , performing the first mode of operation is not required, and the energy used for the operation of the compressor (111) can be reduced. In addition, in the second mode of operation as well, the compressor (111) can be stopped once to reduce the energy to operate the compressor (111).

  More preferably, the controller (130) executes the third mode of operation when the temperature of the hot water is a first predetermined temperature or more.

  As a result, the heat can be absorbed from the hot water, so that the defrost effect due to the execution of the third mode of operation can be reliably obtained.

  More preferably, the controller (130) stops the third mode of operation when the water temperature is below the first predetermined temperature.

  As a result, the heat can not be sufficiently absorbed from the hot water, so that the third mode of operation is stopped.

  More preferably, the controller (130) stops the operation of the compressor (111) when the temperature of the hot water is a second predetermined temperature set to a value greater than the first predetermined temperature.

  As a result, the temperature of the hot water is sufficiently increased, so that there is no problem even if the heat of the hot water is stopped by the first mode of operation and the operation of the compressor (111). stopped.

  More preferably, the heater (122) is provided with an air flow tilt flap (123a) increasing the amount of use air for heating supplied to the heater (122) by increasing its own degree of opening, and the control device (130) executes the third mode of operation when the degree of opening is a predetermined degree of opening or less, and stops the third mode of operation when one is above the predetermined degree of opening.

  Therefore, when the opening degree of the air flow tilting flap (123) is a predetermined opening degree or less, such a high temperature of the air conditioning air heated by the air conditioner Heating (122) is not required, so the third mode of operation is preferably performed. Further, when, above the predetermined opening degree, a high temperature of the air conditioning air from the heater (122) is required, also the third mode of operation is stopped so that that the heat is no longer absorbed from the hot water and the heating temperature can be ensured.

  More preferably, the controller (130) evaluates a possibility of executing the second mode of operation or the third mode of operation based on an operating time of the first mode of operation, or on the basis of a temperature difference of the outside air temperature and at least one of the refrigerant temperature at the outdoor heat exchanger (114) including the refrigerant piping portions or its surface temperature or the outside air temperature after passing through the outdoor heat exchanger (114).

  As a result, the defrosting requirement due to the execution of the second mode of operation or the third mode of operation becomes obvious and efficient defrosting becomes possible.

  More preferably, the 30U com device (1J) stops performing the second operating mode or the third operating mode when the refrigerant temperature at the outdoor heat exchanger (114), including the refrigerant piping portions, or its surface temperature is a third or more predetermined temperature.

  As a result, the state of elimination of the frosted state in the outdoor heat exchanger (114) can be clarified and the minimum required measurement of the second mode of operation or the third mode of operation can be performed.

  More preferably, the refrigerant is carbon dioxide.

  As a result, when a carbon dioxide refrigerant is available, the flow rate and the circulating mass can be increased compared with an ordinary refrigerant such as CFC, also a heat transfer by the carbon dioxide refrigerant. becomes possible. In particular, it becomes possible to manage the defrost through the second and third modes of operation in a short time.

  In addition, according to a second aspect of the present invention, there is provided a controller for a heat cycle system. The technical significance is substantially the same as that of the heat cycle system of the first aspect of the present invention.

  In addition, according to a third aspect of the present invention, there is provided a control method for a heat cycle system. The technical significance is substantially the same as that of the control device of the second aspect of the present invention.

  Note that the numerals in parentheses after the above means indicate the correspondence with the specific means described in the embodiments mentioned later.

BRIEF DESCRIPTION OF THE DRAWINGS

  These and other objects and features of the present invention will become more apparent from the following description of the preferred embodiments given with reference to the accompanying drawings, in which: FIG. 1 is a simplified view of the configuration; global y. In a first embodiment of the present invention, FIGS. 2A-2C are views for explaining the operating state at the time of a heating operation (mode of operation). Figure 3 is a first part of a flowchart of the control executed by the controller in the first embodiment of the present invention. Figure 4 is a second part of a flowchart. of the command executed by the control device in the first embodiment of the present invention, FIG. 5 is an explanatory view of the operating state at the time of a defrosting operation (defrost mode 2). Fig. 6 is a first part of a flow chart of the control executed by the controller in a second embodiment of the present invention; Fig. 7 is a first part of a flowchart of the control executed by the controller in a third embodiment of the present invention, and Fig. 8 is a simplified view of the overall configuration of a heat cycle system in a fourth embodiment of the present invention.

  DESCRIPTION OF THE PREFERRED EMBODIMENTS

  Preferred embodiments of the present invention will be described in detail below with reference to the accompanying figures.

  First Embodiment Below, a heat cycle system 100 of a first embodiment of the present invention will be explained with reference to FIGS. 1 to 5. FIG. 1 is a simplified view of the overall configuration of the system. 100, FIGS. 2A to 2C are views for explaining the operating state at the time of a heating operation (hot water heating mode), FIG. 3 and FIG. of the flowchart of the command executed by the control device 130, and Figure 5 is an explanatory view of the operating state at the time of a defrosting operation (defrosting mode 2).

  As shown in FIG. 1, the heat cycle system 100 is mounted on a vehicle having a motor 10 as a drive source for operation and can be used not only for its intrinsic heating operation, but also for a cooling operation. It consists mainly of a heat pump cycle 110, an inner device 120 comprising a central portion of the heater 122, a controller 130, etc. Here, the refrigerant used to flow through the heat pump cycle 110 is carbon dioxide (CO2). The system is sometimes used in a state where the pressure on the high pressure side is greater than a critical pressure.

  The engine (corresponding to the heat emitting device in the present invention) is provided with a cooling circuit 11. The cooling circuit 11 is provided with a radiator 11a. A not shown water pump is used to circulate the cooling water (hot water) for cooling the engine through the interior of the cooling circuit 11. The radiator 11a is used to set (control) the temperature of the the cooling water at a predetermined temperature range (e.g. 90 to 110 C). In addition, the motor 10 is provided with a hot water circuit 12. A not shown water pump is used to circulate the above cooling water (hot water) inside. The hot water circuit 12 (here the output of the engine 10) is provided with a water temperature sensor 12a for detecting the temperature of the hot water flowing therethrough. A temperature signal emitted by the water temperature sensor 12a is inputted to a control device explained later 130.

  The heat pump cycle 110 is formed by a compressor 111, a water-coolant heat exchanger 112, an expansion valve using heat (corresponding to the pressure reducing valve in the present invention) 113, an external device ( corresponding to an external heat exchanger in the present invention) 114, a channel tilting valve 115, an expansion valve 116, an inner device 117, and an accumulator 118 successively connected in a ring shape and a bypass channel 115a derived from the channel tilt valve 115 and connected to an input side of the accumulator 118.

  Further, an indoor heat exchanger 119 is provided for heat exchange between the high pressure side refrigerant flowing between the channel tilt valve 115 and the expansion valve 116 (high temperature refrigerant) and the refrigerant the low pressure side circulating between the accumulator 118 and the compressor 111 (low temperature refrigerant).

  Of the devices 111 to 119 forming the heat pump cycle 110, the expansion valve 116 and the inner device 117 are arranged as components of the indoor unit later explained 120 inside the passenger compartment interior of the dashboard), while the other devices (111 to 115, 118 and 119) are arranged inside the engine compartment of the vehicle.

  The compressor 111 is a fluid machine driven by an electric motor not shown and discharging the compressed refrigerant at high temperature and high pressure. The refrigerant discharge rate can be varied through the speed of operation. The compressor 111 is controlled in operation and in the discharge rate of the refrigerant by the subsequently explained control device 130. In addition, the unloading side of the compressor 111 (between the compressor 111 and the water-refrigerant heat exchanger 112) is provided with a temperature sensor llla for detecting the temperature of the discharged refrigerant and a pressure sensor lllb for detecting the refrigerant pressure. The temperature signal and the pressure signal emitted by the sensors 11a and 11b are designed to be inputted to the control device explained later 130. In addition, the compressor 111 can be passed from a motor drive mode. above motor to a motor drive mode having a variable displacement mechanism and driven by the motor 10 through the clutch of a clutch mechanism.

  The water-coolant heat exchanger 112 is a heat exchanger whose interior is formed with a refrigerant channel and a hot water channel facing each other. The refrigerant channel conveys the refrigerant discharged from the compressor 111, while the hot water channel conveys hot water from the hot water circuit 12. The water-refrigerant heat exchanger 112 exchanges heat between the refrigerant and the refrigerant. 'Hot water.

  The heating expansion valve 113 is a pressure reducing means for reducing the pressure (making the temperature low and the low pressure) of the refrigerant leaving the heat exchanger and the coolant 112. The control device 130 explained later is used to vary its degree of opening and adjust the amount of pressure reduction. In addition, as the degree of opening of the valve varies from small side to large side the amount of refrigerant pressure reduction decreases. At the maximum valve opening degree, it is possible to set a function without pressure reduction.

  The external device 114 is a heat exchanger arranged at the front of the engine compartment of the vehicle (for example behind the front grille), and exchanging the heat between the refrigerant coming out of the heating use expansion valve 113 and the air outside entering the engine compartment. The refrigerant output side of the external device 114 (between the external device 113 and the channel tilt valve 115) is provided with a temperature sensor 114a for detecting the temperature of the refrigerant exiting the outdoor device 114. The temperature signal emitted by the temperature sensor 114a is designed to be inputted to the control device explained later 130.

  The channel tilt valve 115 is a three-way valve for tilting the flow of refrigerant from the outdoor device 114 to the side of the bypass channel 115a (i.e. towards the accumulator 118) or the side of the indoor heat exchanger 119 (i.e. the side of the expansion valve 116). It is controlled in channel switching operation through the control device 130 explained later.

  The expansion valve 116 is a pressure reducing means for reducing the pressure (making the temperature low and the low pressure) of the refrigerant leaving the external device 114 when the channel tilting valve 115 is tilted towards the heat exchanger 119. This expansion valve 116 has a temperature sensing portion 116a and a capillary 116b connected thereto and is a mechanical type expansion valve whose opening degree of expansion valve 116 is adjusted in accordance with the temperature of the In particular, when the refrigerant temperature at the temperature sensing portion 116a is high, the degree of opening is changed to the smaller side, so that the refrigerant pressure at the level of the temperature sensing portion 116a is high. of the outer device 114 is held at the high side, while conversely, when the refrigerant temperature at the of the temperature sensing portion 116a becomes low, the opening degree is changed to the larger side so that the refrigerant pressure at the outer device 114 is kept low.

  The inner device 117 is a heat exchanger arranged to cut through the entire channel within the air conditioning case 121 of the indoor unit 120 and exchange heat between the reduced pressure refrigerant. at the expansion valve 116 and the air conditioning air flowing through the air conditioning housing 121 so as to cool the air conditioning air. The downstream side of the air-conditioning air flow of the inner device 117 is provided with a temperature sensor 117a for detecting the temperature of the cooled air. The temperature signal detected by this temperature sensor 117a is designed to be inputted to the control device 130 explained later.

  The accumulator 118 receives the refrigerant exiting the inner device 117, separates the vapor and liquid phases from the refrigerant, stores the liquid refrigerant and sends the gaseous refrigerant and a small amount of liquid refrigerant near the bottom (where oil is dissolved) through the indoor heat exchanger 119 to the side of the compressor 111.

  In addition, the indoor heat exchanger 119 is a heat exchanger intended primarily to supercool coolant leaving the external device 114 and intended to superheat the refrigerant leaving the inner device 117 (accumulator 118) at the time of a cooling operation to to increase the enthalpy in the inner device 117 and to increase the cooling capacity.

  The air-conditioning housing 121 of the indoor unit is provided, in addition to the interior device 117 above, with a heater central portion 122 serving as a heater. The central heater portion 122 is arranged on the downstream side in the air conditioning air flow from the interior device 117. The central heater portion 122 is a heat exchanger connected to the hot water circuit. 12 to ensure that hot water circulates inside it and to use hot water as a heat source to heat the air conditioning air circulating through it. this. Further, between the heater central portion 122 and the air conditioning housing 121, a bypass duct 124 for circulating the air conditioning air bypassing the central heater portion 122 is form.

  The central heater portion 122 and the bypass duct 124 are provided with air mixing hatches (corresponding to the air flow tilt flaps in the present invention) 123a and 123b for controlling the amounts of the air conditioning air passing therethrough. The air mixing hatch 123a is a swivel type hatch which opens and closes the air conditioning air duct of the central heating unit 122, while the air mixing flap 123b is a pivoting type hatch which opens and closes the bypass duct 124. In accordance with the opening degrees of the flaps 123a and 123b, the ratio of the flow rates of the heating air flowing through the central heating element 122 and the the cooling air flowing through the bypass duct 124 is set and the temperature of the air conditioning air on the downstream side of the heater central portion 122 is set.

  For example, if the air mixing flap 123a is fully open and the air mixing flap 123b is completely closed, the result is the maximum heating mode (Maxhot) of the central heater portion 122, while conversely, if the air mixing flap 123a is completely closed and the air mixing flap 123b is fully open, the result is the maximum cooling mode (Maxcool) of the interior device 117. The opening of the two hatches 123a and 123b are, respectively. designed to be controlled by the control device 130 explained later. In addition, the two hatches 123a and 123b are not limited to pivot types and can also be rotary types or sliding types, etc. The downstream side of the central heater portion 122 in the indoor unit 120 is connected to a plurality of ports in the passenger compartment. The air conditioning air whose temperature is regulated by the air mixing flaps 123a and 123b is intended to be blown into the passenger compartment from the selected orifices.

  A control device serving as control means (below the ECU) 130 consists of a microcomputer and its peripheral circuits. It processes the various types of signals from the water temperature sensor 12a, the temperature sensor 111a, the pressure sensor 111b, the temperature sensor 114a, the temperature sensor 117a, a non-vehicle speed sensor. shown, and an external air temperature sensor not shown in accordance with a preset program and controls the operation and discharge amount of the compressor 111, controls the degree of opening of the heating expansion valve 113, flips channels of channel flip valve 115, and controls opening degrees of air mixing flaps 123a and 123b for cooling operation, heating operation, and defrosting operation at time of operation of heating explained below.

  In addition, the heat pump cycle 110 is provided with two valves for the refrigerant charge or the refrigerant discharge. That is, a high pressure valve 119a is arranged between the heat exchanger of the coolant on the high pressure side 112 and the expansion valve for heating use 113, while a low pressure valve 119b is arranged between the inner device of the low pressure side 117 and the accumulator 118. In particular, with regard to the setting position of the high pressure valve 119a, it is taken into account the fact of ensuring the reliability of the elements of the sealing for the valve (rubber elements), etc. and a position, where the refrigerant from the compressor 111 is reduced in temperature by the water-coolant heat exchanger 112 and the temperature conditions are facilitated, is selected.

  Then, the operation on the basis of the above configuration will be explained.

  1. Cooling operation The ECU 130 fully opens the heating use expansion valve 113 and opens the channel tilt valve 115 to the side of the indoor heat exchanger 119 to operate the compressor 111. That being so, the refrigerant discharged from the compressor 111 flows through the route: water-coolant heat exchanger 112 -> heating-use expansion valve 113 --k external device 114 - * channel 115 tilting valve - -Inner heat exchanger 119 --- expansion valve 116 - + inner device 117, accumulator 118 - * indoor heat exchanger 119 - * compressor 111.

  Here, since the heating duty expansion valve 113 is fully open in the state, the pressure reduction function of the heating duty expansion valve 113 does not occur, and the high temperature, high pressure refrigerant discharged from the compressor 111 discharges heat to the hot water of the hot water circuit 12 at the indoor heat exchanger 119 to thereby be cooled. Further, the cooled refrigerant, whose pressure is reduced at the expansion valve 116 whose opening degree is set by the temperature sensing portion 116a, and the capillary 116b, enters the inner device 117, is evaporated by air conditioning air, and cools the air conditioning air through the latent heat of vaporization at this time. The ECU unit 130 controls the unloading amount of the compressor 111 and the opening degrees of the air mixing hatches 123a and 123b (mainly by ensuring that the hatch 123a is completely closed and the hatch 123b completely open), so that the temperature of the air conditioning air detected by the temperature sensor 117a becomes the set temperature set by the passenger.

  2. Heating Operation The ECU 130 opens channel flip valve 115 to branch channel 115a, drives compressor 111, and controls the degree of opening of heating expansion valve 113 to a degree. predetermined opening (small degree of opening). That being so, the refrigerant discharged from the compressor 111 flows through the route: heat exchanger and coolant 112 - * expansion valve for heating use 113> external device 114 -> channel 115 tilting valve -> channel branch 115a> accumulator 118, indoor heat exchanger 119 - + compressor 111.

  Here, the high temperature, high pressure refrigerant discharged from the compressor 111 discharges heat to the hot water of the hot water circuit 12 at the water-cooler heat exchanger 112 and heats the hot water. In addition, the heated hot water vents heat to the air conditioning air at the central heater portion 122 to heat the air conditioning air. The ECU unit 130 controls the unloading amount of the compressor 111 and the opening degrees of the air mixing hatches 123a and 123b (mainly by making the hatch 123e completely open and the hatch 123b completely closed) to adjust the temperature of the air conditioning air.

  In addition, the refrigerant exiting the heat exchanger and the coolant 112 has its reduced pressure through the heating expansion valve 113 and enters the external device 114. In this case, as shown in FIG. 2A, if at a stage where the temperature of the hot water is low, for example at the initial starting period of the engine 10 (for example -20 C), a large amount of heat evacuated is obtained at the level of the water-heat exchanger. refrigerant 112, the pressure is reduced to the two-phase vapor-liquid region and the refrigerant absorbs heat from the outside air into the outdoor device 114 and returns to the compressor 111. In addition, as shown in FIG. 2B at the same time as increasing the temperature of the hot water at the same time as the flow of time (eg 35 C), the amount of heat discharged at the water-coolant heat exchanger 112 and the amount of The heat absorbed at the outer device 114 decreases. As indicated in FIG. 2C, when a sufficient temperature of the hot water is obtained (for example 70 ° C.), the refrigerant after evacuating heat at the water-refrigerant heat exchanger 112 has its reduced pressure. at the superheated gas region and the heat is emitted from the refrigerant to the outside air in the outdoor device 114. In addition, the mode of operation of Figs. 2A to 2C corresponds to the first mode of operation of the present invention. In particular, the mode of operation of Figure 2C after the hot water temperature increases, will be referred to hereinafter as the "hot water heating mode".

  3. Defrosting Operation In the initial stage, at the time of the above heating operation (FIGS. 2A and 2B), the absorption of heat by the refrigerant from the outside air at the outer device 114 brings the surface of the external device 114 to frost, also a defrosting operation becomes necessary. Based on the control flowchart shown in Fig. 3 and Fig. 4, the ECU 130 performs defrosting operation (steps S160 and S180) in accordance with various conditions by executing a heating operation (step S190).

  First, in step S50, the ECU 130 starts counting a timer for counting the operating time of the heat pump cycle 110 (heating operation time). Then, in step S100, it reads the outdoor air temperature TAM from the outdoor air sensor, the refrigerant temperature Tgcout at the outlet side of the outdoor device 114 (hereinafter referred to as the "refrigerant temperature"). of the external device ") from the temperature sensor 114a, the vehicle speed from the vehicle speed sensor, the hot water temperature TW from the hot water sensor 12a, and the refrigerant temperature TD from level of the discharge side of the compressor 111 (hereinafter referred to as the "refrigerant temperature discharged") from the temperature sensor llla.

  In step S110, it is evaluated, as the first evaluation of icing by the timer, whether frost is or is not formed on the external device 113. That is, when the elapsed operating time of the Heat pump cycle 110 is not a preset predetermined time or more (for example 2 hours), it is judged that there is no icing and the program goes to step S120, whereas when the predetermined time or more has elapsed, it is judged that there is icing and the program proceeds to step S130.

  Then, in step S120, a second evaluation of the icing is evaluated. In this case, it is evaluated whether a temperature difference equal to the outdoor air temperature TAM minus the external device coolant temperature Tgcout is a predetermined value or more. That is, icing occurs when the external device coolant temperature Tgcout is lower than the outside air temperature TAM. If the icing progresses, the external device coolant temperature Tgcout drops gradually, so that when the temperature difference with the outside air temperature TAM becomes larger than a predetermined value, it is judged that there is icing . When evaluating icing, the program proceeds to step S130. When it is judged that there is no icing, the program proceeds to step S170.

  Next, in step S130, it is evaluated whether to proceed to a defrosting operation (defrosting capability evaluation). Here, when the hot water temperature TW increases to a first predetermined temperature (for example 60 C) or more, that is to say, as explained later, when heat is absorbed by the refrigerant from the water When the heat is vented to the outside air at the outdoor device 114, it is judged that the defrosting operation is possible and the program proceeds to step S150.

  In addition, when the hot water temperature TW has not increased to the first predetermined temperature, it can not be absorbed heat from the hot water or, if heat is absorbed from the hot water, this would lead to insufficient capacity at the time of a heating operation (heating capacity at the central heating element 122), so that defrosting would not be possible in the heating system. Accordingly, in step 5140, the compressor 111 is stopped once to stop the heat pump cycle 110 itself and eliminate the heat-absorbing action by the refrigerant at the device outside 114 so as to avoid icing. In addition, after that, the program returns to step 5100 where the command is repeated.

  After evaluating in step 5130 that one should switch to deicing operation, it is evaluated based on the vehicle speed (defrost mode evaluation) in step S150, which of two defrost modes explained later one should use to handle that. That is, it is judged whether the vehicle speed is a predetermined vehicle speed (corresponding to a predetermined value when a first predetermined value is equal to a second predetermined value in the present invention). When the vehicle speed is not higher than the predetermined speed, the program switches to the defrost mode 2 control of step S160, whereas, when the vehicle speed exceeds the predetermined speed, the program proceeds to control of defrost mode 1 of step S180.

  Here, the speed of the vehicle used for the evaluation is determined as a physical quantity correlated to the flow of outside air entering the external device 114. If the vehicle speed is high and the outside air flow is high , icing at the outer device 114 is aggravated, while, if the vehicle speed is low and the flow of outside air is low, the defrosting at the outer device 114 becomes easier. Consequently, the defrosting mode is selected taking into account the speed of the vehicle, that is to say the flow rate of the outside air.

  In the defrost mode 2 of step S160 (corresponding to the third mode of operation of the present invention) in the same manner as at the time of the above heating operation, the channel tilt valve 115 is left open to the bypass channel side 115a or the compressor 111 is left in operation and the opening degree of the heating use expansion valve 113 is increased to the fully open side or is fully open in the control (degree of important opening).

  That being the -as, C ,, - ,,. indicated by the figure in step S160 or FIG. 5, the pressure on the discharge side of the compressor 111 is reduced. At the same time, the temperature of the discharged refrigerant TD is maintained at a lower value than the hot water temperature TW and at the water-refrigerant heat exchanger 112 the refrigerant absorbs heat from hot water. The heat-absorbing refrigerant from the hot water is reduced in pressure by the heating-use expansion valve 113, but the degree of valve opening is important, so that the amount of pressure reduction is also and the refrigerant enters the outdoor device 114 to be defrosted at a relatively high temperature.

  In addition, since the degree of valve opening is large, the pressure of the low pressure side also increases, the density of the refrigerant entering the compressor 111 increases, and the flow rate of the refrigerant in circulation also increases. As a result, the high temperature refrigerant can enter the external device 114 at a high rate. The heat is vented to the outside air in a manner increasing the amount of heat removed compared to the hot water heating mode at the time of heating operation, so the defrosting operation is performed immediately.

  In the defrost mode 1 of step S180 (corresponding to the second mode of operation of the present invention), in the same manner as the above heating operation, the channel tilt valve 115 is left open to the side 115a of the bypass channel or the compressor 111 is left in operation, and the opening degree of the heating use expansion valve 113 is adjusted (degree of intermediate opening) to control the pressure of the refrigerant discharged from the compressor 111 (temperature sensor value 111b) and thereby control the temperature of the discharged refrigerant TD to maintain it substantially at the same temperature as the hot water temperature TW. As a result, the amount of heat exchanged between the hot water and the coolant at the water-coolant heat exchanger 112 is kept small so as to maintain the temperature of the hot water TW at to ensure the heating capacity at the central portion of heater 122 by the hot water temperature TW, and to maintain comfort in the passenger compartment. In addition, the compressor work of the compressor 111 is maintained to the minimum extent necessary.

  In addition, the refrigerant, whose pressure has been reduced by the heating expansion valve 113, enters the external device 114 in a state greater than the outside air temperature TAM, the heating-use expansion valve. 113 itself, the refrigerant piping connecting the heating-use expansion valve 113 to the outdoor device 114 and the portions near the refrigerant inlet of the outdoor device 114 are kept at a warm temperature, and the frost deposited near the The refrigerant inlet of the external device 114 is melted in advance as a defrost mode 1.

  Accordingly, by increasing the temperature of the gap between the heating-use expansion valve 113 and the refrigerant inlet of the outdoor device 114 in advance, when a large capacity of the heater is used. step 5160 to defrost, it is no longer necessary to heat these locations. In addition, the frost near the refrigerant inlet of the external device 114 is already melted. As a result, defrosting becomes possible in a short time.

  On the other hand, when the evaluation in step S120 is negative, in step S170, it is evaluated whether a heating operation is necessary according to the hot water temperature TW and either the execution or the suspension hot water heating mode is selected. That is, when the hot water temperature TW has increased to a second predetermined temperature (temperature set to the higher side than the first predetermined temperature, for example 80 C) or more, in step S140, the compressor 111 is stopped and the heat pump cycle 110 itself is stopped. Further, when the hot water temperature TW does not reach the second predetermined temperature, the program proceeds to control the hot water heating mode of step S190 (already explained in the operation section). heating above).

  That is, if the hot water temperature TW has sufficiently increased and has become the second predetermined temperature or more, the heating of the air conditioning air at the central portion of heating 122 can be satisfied by the amount of heat from the engine 10. The heating of the hot water by the hot water heating mode is not necessary. As a result, the problem proceeds to step S140, where the compressor 111 is brought to a stop. Conversely, if the hot water temperature TW has not increased sufficiently and has not reached the second predetermined temperature, the heating of the hot water in the hot water heating mode is favored and the heating capacity air conditioning air at the central heater portion 122 is provided by controlling the hot water heating mode of step S190. After the command of step S190, the program returns to step S50.

  Further, after step S160 and step S180, in step S200, it is judged whether defrosting is complete. Here, when the external device coolant temperature Tgcout has become the predetermined temperature (corresponding to the third predetermined temperature in the present invention) or more, it is judged that the defrost is complete. If the defrost is judged to be completed, in step S210, the operating time (timer) of the heat pump cycle 110 is reset and the program proceeds to step S50. In addition, if the evaluation in step S200 is negative, the program proceeds to step S100 where the above command is repeated.

  As explained above, in the present embodiment, the tilting of the refrigerant flow through the channel tilt valve 115 enables cooling operation in addition to heating operation. In the cooling operation by the compressor 111, the water-coolant heat exchanger 112, the external device 114, the expansion valve 116 and the inner device 117, at the initial stage of the engine start 10, the hot water is positively heated by the water-coolant heat exchanger 112, the reheating of the engine 10 is accelerated, and an effect of improving fuel efficiency is obtained. Further, by evacuating heat in the hot water through the water-coolant heat exchanger 112 before the refrigerant enters the outdoor device 114, a heat removal action combined with the device external 114 is obtained and the coolant temperature at the outlet of the external device 114 can be decreased, so that, as a result, the cooling performance can be improved.

  In addition, in the heating operation by the compressor 111, the water-coolant heat exchanger 112, the heating-use expansion valve 113, the outdoor device 114 and the heater central portion 122 (heating mode Also, by heating the hot water at the initial stage of starting the engine 10, the heating is accelerated and an effect of improving the fuel efficiency is obtained. In addition, the earlier increase of the hot water temperature allows the heat removal performance at the central heater portion 122 to be improved as well and allows the heating performance to be improved.

  Further, in the present embodiment, in the above heating operation (hot water heating mode), a defrosting operation for defrosting the outdoor device 114 (defrost mode 1 and defrost mode 2) by the compressor 111, the water-coolant heat exchanger 112, the heating-use expansion valve 113, and the exterior device 114 are made possible.

  By executing the defrost mode 1 for executing the hot water heating mode, the heat of the compressor work at the compressor 111 can be exhausted to the outside air at the outdoor device 114 without affecting the temperature of the hot water heating mode. hot water, so the heating of the outside air side becomes possible. That is, icing can be prevented at the outer device 114 from an early stage. Further, by executing the defrost mode 2, the heat of the compressing work at the compressor 111 and the heat absorbed from the hot water can be exhausted to the outside air at the outer device 114, so that the amount of heat evacuated can be increased, and that the external device 114 can be defrosted. In addition, the changeover to the defrost mode 1 and defrost mode 2 can be managed simply by changing the opening degree of the heating use expansion valve 113 to the larger side without changing the flow direction of the heater. refrigerant, so that instant defrost becomes possible.

  Further, by executing the defrost mode 2, by causing the opening degree of the heating duty expansion valve 113 to be fully open, it becomes possible to reduce the pressure on the high pressure side which becomes the unloading side at the the level of the compressor 111 to the maximum extent and to increase the amount of heat absorbed from the hot water, so that it is possible to increase the amount of heat evacuated at the outer device 114 and improve the defrost effect.

  In addition, switching from the hot water heating mode to defrost mode 1 or defrost mode 2 or switching from defrost mode 1 to defrost mode 2 can be managed simply by changing the degree of opening of the expansion valve for heating purposes 113 in the opening direction while still using the compressor 111, so that the transition to the defrost mode 1 or the defrost mode 2 does not require the time required for stopping and restarting the compressor 111, and the time until the pressure in the heat pump cycle 110 is stabilized and accordingly the defrost becomes possible in a short time (instantaneously).

  Further, when the vehicle speed (i.e., the value correlated with the flow of outside air entering the outdoor device 114) exceeds a predetermined speed, the defrost mode 1 is executed. As a result, when the flow of outside air entering the outdoor device 114 exceeds a predetermined value, the conditions become more favorable for cooling the outdoor device 114 through the outside air. Accordingly, in this case, the defrost mode 1, which does not affect the temperature of the hot water, is preferably performed.

  On the other hand, when the vehicle speed is the predetermined speed or less, the defrost mode 2 is executed. Therefore, if the flow of outside air entering the outdoor device 114 has a predetermined value or less, the conditions become detrimental to the cooling of the outdoor device 114 by the outside air, also defrosting by the defrost mode 2 is preferably executed.

  In addition, when the hot water temperature TW is a first predetermined temperature (for example 60 C) or more, the defrost mode 2 is executed, so that heat can be absorbed from the hot water, the absorbed heat can be discharged at the external device 114, and the defrosting effect can be reliably ensured.

  Conversely, when the hot water temperature TW is lower than the first predetermined temperature, the heat can not be sufficiently absorbed from the hot water, so that the defrost mode 2 is preferably stopped (the compressor It is stopped in step S140).

  Further, when the hot water temperature TW is a second predetermined temperature set higher than the first predetermined temperature, or more, the hot water temperature TW is sufficiently increased, so that There is no problem even if the stopping of the heating of the hot water by the hot water heating mode and the compressor 111 is preferably stopped.

  Further, as a defrost evaluation, it is evaluated whether the defrost mode 1 or the defrost mode 2 can be executed based on the operating time in the hot water heating mode (pump cycle 110) or on the basis of the temperature difference between the outside air temperature TAM and the external device coolant temperature Tgcout, also the need for defrosting by the execution of the defrost mode 1 or the defrost mode 2 becomes obvious and effective defrost becomes possible.

  In addition, when the external device coolant temperature (Tgcout temperature) is a predetermined temperature (third predetermined temperature) or more, the execution of defrost mode 1 or defrost mode 2 is stopped, so that the state The frost-state removal in the outdoor device 114 can be clarified and the minimum required measurement of defrost mode 1 or defrost mode 2 can be performed.

  In addition, carbon dioxide is used as a refrigerant in the heat pump cycle 110. When carbon dioxide is adopted as a refrigerant, the temperature and the circulating mass can be increased as compared to an ordinary refrigerant such as that CFC, also an efficient heat transfer by the carbon dioxide refrigerant becomes possible. In particular, it becomes possible to perform defrosting through defrost mode 1 and defrost mode 2 in a short time.

  Second Embodiment A second embodiment of the present invention is shown in FIG. 6. The second embodiment differs from the first embodiment in that, before evaluating the defrosting operation possibility of the step S130, step S130 is added as the first defrost operation possibility evaluation (step S130 becomes the second defrost operation possibility evaluation), step S150 becomes an evaluation of the first defrost mode, and a next step S150A is provided as an evaluation of the second defrost mode.

  That is, after step S110, the ECU 130 executes, as the first de-icing operation possibility evaluation at step S130A, an evaluation that the degree of openness of the air mixing flap 123a on the heating central portion 122 side is a first predetermined opening degree or less. If it is the first or predetermined opening degree, it proceeds to step S130, where it performs the second defrost operation possibility evaluation based on the hot water temperature TW. In this case, the degree of opening of the air mixing flap 12.3a, which is the first predetermined opening degree or less, indicates the case where the temperature of the air conditioning air heated by the Central portion of heater 122 should not be so high. Further, if the evaluation in step S130A is negative, the ECU 130 proceeds to step S140, where it causes the compressor 111 to stop.

  Further, when the evaluation at the evaluation of the first deicing mode of step S150 is affirmative, the ECU 130 evaluates as an evaluation of the second defrost mode at step S150A if the degree of opening of the air mixing flap 123a on the side of the heater central portion 122 is a second or greater predetermined opening degree. If it evaluates that it is not, it goes to step S160, where it executes the defrost mode 2. If it evaluates that it is the case in step S150A, it goes to step S180, where it executes the defrost mode 1. Here again, in the same manner as above, the fact that the opening degree of the air mixing flap 123a does not reach the second degree of opening predetermined indicates the case where the temperature of the air conditioning air heated by the heater central portion 122 need not necessarily be so high (however, the first predetermined degree of opening the second predetermined degree of opening).

  Therefore, when the temperature of the air conditioning air required at the time of heating is not so high, the defrost mode 2 is executed, also an effective defrosting using the heat of the hot water becomes possible . Conversely, when the temperature of the air conditioning air required at the time of heating is high, the compressor 111 is stopped (step S140) or the defrost mode 1 is executed, so that the heating temperature can be ensured. without absorbing heat from hot water.

  Third Embodiment A third embodiment of the present invention is shown in Fig. 7. The third embodiment differs from the first embodiment in that step S145 for reading the hot water temperature TWs to time of defrost start is added after step S130. In addition, step S150 becomes an evaluation of the first defrost mode and a next step S150B is provided as an evaluation of the second defrost mode.

  The ECU 130 evaluates, as an evaluation of the second defrost mode in step S150B, whether ATW is a predetermined value or more. Here, ATW is the hot water temperature TWs at the start of the defrost read in step 5145 minus the hot water temperature TWn at the present time. The larger the ATW, the greater the drop in the indicated TW hot water temperature. Accordingly, if ATW does not exceed a predetermined value, the fall of the hot water temperature TW is "t; t and the ECU 130 proceeds to step S1GO where it executes the defrost mode 2. In addition, if ATW has the predetermined value or more, the fall of the hot water temperature TW is important.To avoid the absorption of heat from hot water, the ECU 130 proceeds to step S180 where it executes the defrost mode 1.

  As a result, it is possible to reliably prevent the hot water temperature TW from dropping significantly during the execution of the defrost mode 2, so that it is possible to prevent an effect. harmful to the heating performance.

  Fourth Embodiment A fourth embodiment of the present invention is shown in FIG. 8. The fourth embodiment differs from the first embodiment in that the configuration of the heat pump cycle 110 is changed to the pump cycle. 110A heat. That is, the coolant heat exchanger 112 is arranged on the downstream side of the heater central portion 122 and the channel swing valve 115 is arranged between the indoor heat exchanger 1.19 and the valve. 116A. In addition, the expansion valve 116A becomes a fixed opening valve requiring no temperature sensing portion 116a and capillary 116b. In addition, the low pressure pump 119 is arranged between the accumulator 118 and the indoor heat exchanger 119.

  As a result, the heat pump cycle 110A has similar actions and effects to those of the first embodiment.

  Note that the indoor heat exchanger 119 can be removed depending on the cooling capacity of the outdoor device 117 in the cooling operation. In addition, the channel tilt valve can be made to be a solenoid valve instead of a three way valve. Other Embodiments During the execution of the defrost mode 2 of step 5160 of the first embodiment, the unloading amount of the compressor 111 can be made equal to the maximum amount. By this means, it is possible to increase the amount of heat evacuated at the external device 114, so that it is possible to further improve the defrosting effect.

  In addition, in the evaluation at step 5150, the vehicle speed was used, but the vehicle speed can be replaced by the engine speed 10, the number of vehicle tire revolutions, the air flow rate external entering the external device 114 directly, a stop signal of the vehicle (or a start signal of the vehicle), etc. Further, in step S150, for evaluating the value of the vehicle speed, it is also possible to provide a first predetermined speed (corresponding to a first predetermined value in the present invention) and a second predetermined speed plus smaller than the first predetermined speed (corresponding to a second predetermined value of the present invention), to evaluate negatively when the speed of the vehicle exceeds the first predetermined speed, and to evaluate affirmatively when it is equal to the second predetermined speed or lower.

  Further, in the evaluation of the vehicle speed in step 5150, it is also possible to stop the compressor 111 if the rated vehicle speed is a predetermined speed or more. Therefore, as when the vehicle speed is high, the hot water temperature TW is increased by the heat removed from the engine itself and the heating capacity of the heater central portion 122 is ensured. , the execution of the hot water heating mode is not required and the energy used for the operation of the compressor 111 can be reduced. In addition, in the defrost mode 1 also, the compressor 111 can be stopped once to reduce the energy to operate the compressor 111.

  In the control for stopping the compressor 111 through the above evaluation of the vehicle speed, the evaluation can be performed on the basis of the engine speed and the operating time. That is, it is also possible to stop the operation of the compressor 111 in the control when the speed of the motor 10 exceeds a predetermined speed for a predetermined time.

  Further, with respect to the second icing evaluation of step 5120, the evaluation is performed using the calculated temperature difference through the outside air temperature TAM the outside device refrigerant temperature Tgcout, but the external device coolant temperature Tgcout can be replaced by the surface temperature of the outer device 114 having the piping portions or the outside air temperature after it has passed through the external device 114.

  Further, with respect to the evaluation of the defrost completion of step S200, the evaluation is performed using the value of the external device coolant temperature Tgcout, but it is also possible to use the surface temperature of the outer device 114 including the pipe portions.

  In addition, the refrigerant used for the heat pump cycle 110 is not limited to CO2. A standard CFC-based refrigerant can also be used.

  In addition, the central heater portion 122 has been explained as being a portion utilizing hot water circulated from the engine 10 as a heat source, but the invention is not limited thereto. It is also possible to use hot water from a fuel cell in a fuel cell vehicle as a source of heat. In addition, the heat cycle system 100 is not limited to use on a vehicle and may also be for home use.

  Although the invention has been described with reference to specific embodiments chosen for illustrative purposes, it should be obvious that many modifications could be made to it by those skilled in the art without departing from the basic concept and scope of the invention.

Claims (45)

  A heat cycle system comprising: a compressor (111) discharging a compressed refrigerant at a high temperature and a high pressure, a water-coolant heat exchanger (112) exchanging heat between the refrigerant discharged from said compressor ( 111) and the hot water used to adjust the temperature of a heat-emitting device (10) and used as a heat source of a heater (122), a pressure-reducing valve (113) whose degree of opening can be varied and capable of reducing the pressure of the refrigerant discharged from said heat exchanger (112), an external heat exchanger (114) exchanging heat between the refrigerant exiting from said heat reduction valve; pressure (113) and the outside air and returning 1.y said refrigerant to the side of said compressor (111), and a control device (130) for executing one of a the first mode of operation controlling said degree of opening to a predetermined degree of opening to cause said water-coolant heat exchanger (112) to discharge heat from said coolant to said hot water, a second mode of operation controlling said degree of opening such that the temperature of said refrigerant discharged from said compressor (111) becomes substantially equal to a temperature of said hot water at said water-coolant heat exchanger (112) to cause said outdoor heat exchanger (114) to discharging heat from said coolant to said outside air, and a third mode of operation rendering said degree of opening larger than in said second mode of operation so as to decrease the pressure of said refrigerant discharged from said compressor (111) in order to causing the temperature of said refrigerant to be lower than said temperature of said e in the hot state, and thereby causing said coolant heat exchanger (112) to cause said coolant to absorb heat from said hot water and to cause said external heat exchanger (114) to cause said coolant to exhaust heat to said outside air.   The heat cycle system of claim 1, wherein said controller (130) causes said degree of aperture to be fully open when performing said third mode of operation.   The heat cycle system of claim 1 or claim 2, wherein said controller (130) makes the unloading amount of said maximum compressor (111) during execution of said third mode of operation.   A heat cycle system according to any one of claims 1 to 3, wherein said controller (130) switches from said first mode of operation to said second mode of operation or said third mode of operation and switches from said second mode operating in said third mode of operation by varying said opening degree in the opening direction while operating said compressor (111).   A heat cycle system according to any one of claims 1 to 4, wherein said system is mounted on a vehicle and said controller (130) controls said second mode of operation when a flow of said incoming outside air in said outdoor heat exchanger (114) or a physical quantity correlated to the flow rate exceeds a first predetermined value or when said vehicle is in motion.   A heat cycle system according to any one of claims 1 to 5, wherein said system is mounted on a vehicle and said controller (130) performs said third mode of operation when a flow of said outside air entering said external heat exchanger (114) or a physical quantity correlated to the flow rate is a second predetermined value or less or said vehicle is stationary.   The heat cycle system of claim 6, wherein said first predetermined value is set to a value of said second or more predetermined value.   The heat cycle system of any one of claims 1 to 7, wherein said system is mounted on a vehicle and said controller (130) stops operation of said compressor (111) when a traveling speed said vehicle is a predetermined speed or more.   The heat cycle system of any one of claims 1 to 8, wherein said controller (130) performs said third mode of operation when the temperature of said hot water is a first predetermined temperature or more.   The heat cycle system of claim 9, wherein said controller (130) stops said third mode of operation when the temperature of said hot water is lower than said first predetermined temperature.   The heat cycle system of claim 9 or 10, wherein said controller (130) stops operation of said compressor (111) when the temperature of said hot water is a second predetermined temperature set to be greater than said first predetermined temperature.   The heat cycle system of any one of claims 1 to 11, wherein said heater (122) is provided with an air flow tilt flap (123a) increasing the amount of air for heating use supplied to said heater (122) by increasing its degree of opening, and said controller (130) executes said third mode of operation when said degree of opening is a predetermined opening degree or less and stopping said third mode of operation when it is above said predetermined degree of opening.   The heat cycle system of any one of claims 1 to 12, wherein said controller (130) evaluates a possibility of performing said second mode of operation or said third mode of operation on the basis of a the operating time of said first operating mode or on the basis of a temperature difference of the temperature of said outside air and at least one of said refrigerant temperature at said outdoor heat exchanger (114) including the piping portions of said refrigerant or its surface temperature or the temperature of said outside air after it has passed through said outdoor heat exchanger (114).   14. A heat cycle system according to any of claims 1 to 13, wherein said control (130) stops said second mode of operation or said third mode of operation when said refrigerant temperature at said outdoor heat exchanger (114), including the piping portions of said refrigerant, or its exterior surface temperature is a third or more predetermined temperature.   The heat cycle system of any one of claims 1 to 14, wherein said refrigerant is carbon dioxide.   16. Control device of a heat cycle system comprising a compressor (111) discharging a compressed refrigerant at a high temperature and a high pressure, a heat exchanger heat exchanger (112) exchanging heat between the refrigerant discharged from said compressor (111) and hot water used to adjust the temperature of a heat-emitting device (10) and used as a heat source of a heater (122), a pressure-reducing valve (113) whose degree of opening can be modified and reducing the pressure of the refrigerant discharged from said water-coolant heat exchanger (112), and an external heat exchanger (114) exchanging heat between the refrigerant exiting said valve for reducing the pressure (113) and the outside air and returning said refrigerant to the side of said compressor (111), said controller (130) executing a one of a first mode of operation controlling said degree of opening to a predetermined degree of opening to cause said water-coolant heat exchanger (112) to discharge heat from said refrigerant to said hot water, a second mode of operation controlling said degree of opening such that a temperature of said refrigerant discharged from said compressor (111) becomes substantially equal to a temperature of said hot water at said water-coolant heat exchanger (112) for bringing said outdoor heat exchanger (114) evacuating heat from said refrigerant to said outside air, and a third operating mode rendering said opening degree greater than in said second operating mode so as to decrease the pressure of said refrigerant discharged from said compressor (111). ) to make the temperature of said coolant lower than the temperature of the lad ite hot water and thereby to cause said water-refrigerant heat exchanger (112) to cause said refrigerant to absorb heat from said hot water and to cause said outdoor heat exchanger (114) to ensure that said refrigerant discharges heat to said outside air.   17. A control device of a heat cycle system according to claim 16, which causes said degree of opening to be fully open during the execution of said third mode of operation.   The control device of a heat cycle system according to claim 16 or 17, which renders an unloading amount of said maximum compressor (111) during the execution of said third mode of operation.   A control device of a heat cycle system according to any of claims 16 to 18, which switches from said first mode of operation to said second mode of operation or said third mode of operation and passes from said second mode of operation. operating in said third mode of operation by changing said degree of opening in the opening direction while operating said compressor (111).   The control device of a heat cycle system according to any one of claims 16 to 19, wherein said system is mounted on a vehicle and performs said second mode of operation when a flow rate of said outside air entering said external heat exchanger (114) or a physical quantity correlated to the flow rate exceeds a first predetermined value or when said vehicle is in motion.   A control device of a heat cycle system according to any of claims 16 to 20, wherein said system is mounted on a vehicle and performs said third mode of operation when a flow rate of said outside air entering said outdoor heat exchanger (114) or a physical quantity correlated to the flow rate is a second predetermined value or less or when said vehicle is stationary.   The control device of a heat cycle system according to claim 21, wherein said first predetermined value is set to a value of said second predetermined value or more.   The control device of a heat cycle system according to any one of claims 16 to 22, wherein said system is mounted on a vehicle and stops the operation of said compressor (111) when a speed of movement of said vehicle is a predetermined speed or more.   The control device of a heat cycle system according to any one of claims 16 to 23, which executes said third mode of operation when the temperature of said hot water is a first predetermined temperature or more.   The control device of a heat cycle system according to claim 24, which stops said third mode of operation when the temperature of said hot water is lower than said first predetermined temperature.   A control device of a heat cycle system according to claim 24 or 25, which stops the operation of said compressor (111) when the temperature of said hot water is a second predetermined temperature, set to be higher than said first temperature predetermined.   The control device of a heat cycle system according to any one of claims 16 to 26, wherein said heater (122) is provided with an increasing airflow tilt hatch (123a). the amount of heating air supplied to said heater (122) by increasing its own degree of opening, and said controller (130) executes said third mode of operation when said degree of opening is a degree of predetermined opening or less and stops said third mode of operation when it is above said predetermined degree of opening.   The control device of a heat cycle system according to any one of claims 16 to 27, which evaluates a possibility of executing said second mode of operation or said third mode of operation on the basis of a time of operating said first mode of operation or on the basis of a temperature difference of the temperature of said outside air and at least one of said refrigerant temperature of said outdoor heat exchanger (114), including parts of piping said refrigerant or its surface temperature or the temperature of said outside air after it has passed through said outdoor heat exchanger (114).   29. Control device of a heat cycle system according to any one of claims 16 to 28, which stops the execution of said second mode of operation or said third mode of operation when said refrigerant temperature at said heat exchanger external heat (114), including the piping portions of said refrigerant, or its surface temperature is a third or more predetermined temperature.   The control device of a heat cycle system according to any one of claims 16 to 29, wherein said refrigerant is carbon dioxide.   31. A method of controlling a heat cycle system comprising a compressor (111) discharging a compressed refrigerant at a high temperature and a high pressure, a heat exchanger heat exchanger (112) exchanging heat between the refrigerant discharged from said compressor (111) and the hot water used to regulate the temperature of a heat-emitting device (10) and used as a heat source of a heater (122), a pressure-reducing valve ( 113) whose degree of opening can vary, and reducing the pressure of the refrigerant discharged from said water-coolant heat exchanger (112), and an external heat exchanger (114) exchanging heat between the refrigerant exiting said valve for reducing the pressure (113) and the outside air and returning said refrigerant to the side of said compressor (111), said controller comprising executing a p-mode a first mode of operation controlling said degree of opening to a predetermined degree of opening to cause said water-coolant heat exchanger (112) to exhaust heat from said coolant to said hot water, a second mode of operation controlling said degree of opening so that a temperature of said refrigerant discharged from said compressor (111) becomes substantially equal to a temperature of said hot water at said water-coolant heat exchanger (112) to bring said outdoor heat exchanger (114) evacuating heat from said refrigerant to said outside air, and a third operating mode rendering said opening degree greater than in said second operating mode so as to decrease the pressure of said refrigerant discharged from said compressor (111). ) to bring the temperature of said coolant lower than the temperature of said hot water and thereby to cause said water-coolant heat exchanger (112) to cause said refrigerant to absorb heat from said hot water and to cause said outdoor heat exchanger (114) to cause said refrigerant to discharge. heat to said outside air.   A method of controlling a heat cycle system according to claim 31, which causes said degree of opening to be fully open when performing said third mode of operation.   A method of controlling a heat cycle system according to claim 31 or 32, which makes an unloading amount of said compressor (111) to be maximum when performing said third mode of operation.   A method of controlling a heat cycle system according to any one of claims 31 to 33, which passes from said first mode of operation to said second mode of operation or said third mode of operation and passes from said second mode of operation to said second mode of operation. third mode of operation by varying said degree of opening in the opening direction while implementing said compressor (111).   A method of controlling a heat cycle system according to any one of claims 31 to 34, wherein said method is used in a vehicle and executes said second mode of operation when a flow rate of said outside air entering said external heat exchanger (114) or a physical quantity correlated to the flow rate exceeds a first predetermined value or when said vehicle is in motion.   A method of controlling a heat cycle system according to any one of claims 31 to 35, wherein said method is used in a vehicle and performs said third mode of operation when a flow rate of said outside air entering said outdoor heat exchanger (114) or a physical quantity correlated to the flow rate is a second predetermined value or less or when said vehicle is stationary.   37. The method of controlling a heat cycle system according to claim 36, wherein said first predetermined value is set to a value of said second predetermined value or more.   A method of controlling a heat cycle system according to any one of claims 31 to 37, wherein said method is used on a vehicle and stops operation of said compressor (111) when the traveling speed of said vehicle is a predetermined speed or more.   A method of controlling a heat cycle system according to any one of claims 31 to 38, which performs said third mode of operation when the temperature of said hot water is a first predetermined temperature or more.   40. A method of controlling a heat cycle system according to claim 39, which stops said third mode of operation when the temperature of said hot water is lower than said first predetermined temperature.   A method of controlling a heat cycle system according to claim 39 or 40, which stops the operation of said compressor (111) when the temperature of said hot water is a second predetermined temperature, set at a value greater than said first predetermined temperature.   42. A method of controlling a heat cycle system according to any one of claims 31 to 41, wherein said heater (122) is provided with an increasing airflow tilt hatch (123a). the amount of heating air supplied to said heater (122) by increasing its own degree of opening, and said method executes said third mode of operation when said degree of opening is a predetermined opening degree or less and stops said third mode of operation when it is above said predetermined degree of opening.   43. A method of controlling a heat cycle system according to any one of claims 31 to 42, which evaluates a possibility of executing said second mode of operation or said third mode of operation on the basis of a period of time. operating said first mode of operation or on the basis of a temperature difference of the temperature of said outside air and at least one of said refrigerant temperature of said outdoor heat exchanger (114), including parts of piping said refrigerant or its surface temperature or the temperature of said outside air after it has passed through said outdoor heat exchanger (114).   44. A method of controlling a heat cycle system according to any one of claims 31 to 43, which stops the execution of said second mode of operation or said third mode of operation when said refrigerant temperature at said heat exchanger. external heat (114), including the piping portions of said refrigerant, or its surface temperature is a third or more predetermined temperature.   45. A method of controlling a heat cycle system according to any one of claims 31 to 44, wherein said refrigerant is carbon dioxide.