JP2002071245A - Heat pump equipment - Google Patents

Abstract

(57) [Summary] [Problem] To prevent freezing trouble in defrosting operation. A load-adaptive operation in which an air heat exchanger (2) functions as a refrigerant evaporator (E) and a load heat exchanger (3) functions as a refrigerant condenser (C), and the liquid heat exchanger (1) operates as a refrigerant evaporator. E, and the main defrosting operation in which the air heat exchanger 2 functions as the refrigerant condenser C, and the anti-load heat exchanger 3 functions as the refrigerant evaporator E, and the air heat exchanger 2 Can be switched to an auxiliary defrosting operation in which the heat exchanger functions as a refrigerant condenser C, and when the defrosting operation for the air heat exchanger 2 is necessary, the heat source side heat medium that exchanges heat with the refrigerant R in the liquid heat exchanger 1 The temperature tb of the liquid Lb, and the temperature tf of the load-side heat transfer fluid Lf for exchanging heat with the refrigerant R in the anti-load heat exchanger 3
And a defrosting control means 14 for automatically selecting and executing the main defrosting operation and the auxiliary defrosting operation according to the conditions.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat pump device, and more particularly, to a heat pump device for exchanging heat between a refrigerant and atmospheric air, which functions as a refrigerant evaporator, and heat exchange between the refrigerant and a load side heat transfer fluid. The present invention relates to a heat pump device that generates heat for various uses by performing a load-corresponding operation in which a load heat exchanger to be operated functions as a refrigerant condenser.

[0002]

2. Description of the Related Art In this type of heat pump device, when a certain amount or more of frost is formed in an air heat exchanger in the above-described load-response operation, a defrosting operation for removing the frost is required. Regarding this defrosting, the operation in which the anti-load heat exchanger functions as the refrigerant evaporator and the anti-air heat exchanger functions as the refrigerant condenser is performed, and the generated heat of condensation in the anti-air heat exchanger is performed. In general, a method of melting frost by frost is adopted.

[0003]

However, in the above-described defrosting operation in which the load heat exchanger functions as a refrigerant evaporator,
Since heat is collected from the load side, for example, when the load device is a snow melting device or a road surface freezing prevention device, there is a possibility that a freezing trouble may be caused on the load device side, and that there is no possibility of such freezing. However, it is not preferable for the load side to collect heat from the load side that requires heat.

In order to solve this problem, a liquid-to-liquid heat exchanger for exchanging heat between the refrigerant and the heat-source-side heat transfer medium is additionally provided. By performing the operation of functioning as a heat exchanger and functioning the air heat exchanger as a refrigerant condenser, heat is collected from the heat source side heat transfer fluid side, eliminating the need for heat collection from the load side. We thought about a device that can perform defrosting, but even with this improved device, in the low-temperature season when frost is formed, heat is collected from the heat-source-side heat transfer fluid in order to remove the heat-source-side heat transfer fluid. There is a problem that a freezing trouble may be caused on the side.

[0005] In view of this situation, the main problems of the present invention are:
It is to prevent defrosting of the air heat exchanger while effectively preventing freezing trouble and effectively reducing heat collection from the load side.

[0006]

Means for Solving the Problems [1] In the invention according to claim 1, an air heat exchanger for exchanging heat between a refrigerant and atmospheric air, and a liquid heat exchange for exchanging heat between a refrigerant and a heat source side heat transfer fluid. A heat exchanger for heat exchange between the refrigerant and the load-side heat medium liquid, a heat exchanger for the load is provided, the heat exchanger for the air functions as a refrigerant evaporator, and the heat exchanger for the load as a refrigerant condenser. A load corresponding operation to function; a main defrosting operation in which the liquid heat exchanger functions as a refrigerant evaporator, and the air heat exchanger functions as a refrigerant condenser; and The frost formed on the air heat exchanger by performing the load corresponding operation is enabled to function as an evaporator and to be switched to an auxiliary defrosting operation in which the air heat exchanger functions as a refrigerant condenser. When the defrosting operation for removing heat is necessary, the heat source side heat transfer fluid Providing a defrosting control unit for automatically selecting out the said auxiliary defrosting operation and the main defrosting operation in accordance with the temperature of the temperature and the load-side heat transfer fluid.

In other words, according to this configuration, when defrosting is required for the air heat exchanger, the above main defrosting operation is performed in which the heat is removed from the heat source side heat transfer medium to perform defrosting, and the load is removed from the load side. The above-mentioned auxiliary defrosting operation for heating and defrosting is automatically selected and executed by the defrosting control means according to the temperature of the heat source side heat transfer fluid and the temperature of the load side heat transfer fluid. If properly set in advance, freezing trouble on the load side such as freezing on the load device side and freezing on the load side heat transfer fluid itself, and,
While effectively preventing freezing trouble on the heat source side heat transfer fluid side such as freezing of the heat collection source causing the heat source side heat transfer fluid to act as a heat source and freezing of the heat source side heat transfer fluid itself, the main defrosting operation is also performed. In a preferred embodiment, the defrosting of the air-to-air heat exchanger can be performed while effectively reducing the heat collection from the load side requiring the heat.

[2] In the invention according to claim 2, claim 1
In the implementation of the invention according to the present invention, a plurality of heat collecting heat exchangers for exchanging the heat source side heat transfer fluid with water are provided, the liquid heat exchanger functions as a refrigerant evaporator, and the heat load In the liquid heat source operation in which the exchanger or the air-to-air heat exchanger functions as a refrigerant condenser, the heat source-side heat medium of the plurality of heat-collecting heat exchangers is passed through the heat source-side heat exchanger. An anti-freezing control means is provided which automatically switches according to the heat exchange state between the medium and the water or at set time intervals.

In other words, in this configuration, in the above-mentioned liquid heat source operation, when the heat source side heat transfer medium exchanges heat with water to take heat from water, there is a possibility that the water is frozen particularly in a low temperature season. In contrast, as described above, a plurality of heat collecting heat exchangers for exchanging the heat source side heat medium liquid with water are provided, and the heat source side heat medium liquid among the plurality of heat collecting heat exchangers passes through the chamber. In the switching use, by automatically switching what is to be performed (that is, what is actually functioning as a heat exchanger) according to the heat exchange state between the heat source side heat transfer fluid and water or at set time intervals, Stop the heat exchange between the heat source side heat transfer fluid and water in each heat collection heat exchanger at the stage before freezing the water, and also stop the heat source side heat transfer fluid from passing through the vessel During the period, to recover the temperature of each heat exchanger for heat collection,
This prevents freezing of the water when collecting heat from the water.

That is, with the above-described configuration in which the freezing of water is prevented by the automatic switching use of the heat-exchanging heat exchanger, the collection of heat from water is completely cut off to prevent the freezing of water. Can be avoided, or such a situation can hardly be reached, and it is possible to stably collect heat from water over a long period of time even in the low temperature season, and in this regard, the heat collecting property is more excellent. Device.

[3] In the invention according to claim 3, claim 1
In the embodiment of the present invention, water is used as the heat source side heat transfer fluid, a plurality of the liquid heat exchangers are provided, the liquid heat exchanger functions as a refrigerant evaporator, and the load heat exchange is performed. In the liquid heat source operation in which the heat exchanger for air or the air heat exchanger functions as a refrigerant condenser, one of the plurality of heat exchangers for liquid passing the refrigerant in the chamber, depending on the heat exchange state between the refrigerant and water. Alternatively, there is provided an anti-freezing control means for automatically switching every set time.

In other words, in this configuration, when the liquid heat source is operated, and water is used as the heat source side heat transfer medium and heat is taken from the water, the water may be frozen particularly in a low temperature season. In contrast, as described above, a plurality of liquid heat exchangers (in this case, heat exchangers for exchanging heat between a refrigerant and water) are provided, and among the plurality of liquid heat exchangers, the refrigerant passes through the inside of the apparatus ( That is, by automatically switching the heat exchanger between the refrigerant and the water according to the heat exchange state between the refrigerant and the water or at set time intervals, each of the liquid heat exchangers is used in the switching use. The heat exchange between the refrigerant and the water in the process is stopped at the stage before the water freezes, and the temperature of each of the liquid heat exchangers is restored during the suspension period in which the passage of the refrigerant through the vessel is stopped. , Thereby obtaining heat from the water, To prevent binding.

That is, according to the above-described structure in which the freezing of water is prevented by the automatic switching use of the liquid heat exchanger, the water is collected from the water in order to prevent the freezing of water. It is possible to avoid a situation in which heat is completely turned off, or to make such a situation hard to occur, and to stably collect heat from water over a long period of time even in a low temperature season. In this respect, it is possible to make the apparatus more excellent in heat collecting property.

The above-mentioned effects of the invention according to claim 2 and the invention according to claim 3 can be obtained also in a heat pump apparatus having no air heat exchanger. In the liquid heat source operation (that is, the main defrosting operation) in which the freezing of water is prevented as described above in the liquid heat source operation that causes the air heat exchanger to function as the refrigerant condenser, the invention according to claim 1. In conjunction with this, freezing trouble on the heat source side heat transfer fluid side during defrosting of the air heat exchanger can be more reliably prevented, and the water can be stably collected for a long period of time even in the low temperature season. In terms of being able to heat, the heat collection from the load side can be more effectively reduced in the defrosting of the air heat exchanger.

In the second aspect of the present invention, the water for heat exchange with the heat source side heat transfer fluid and the water used as the heat source side heat transfer fluid in the third aspect of the invention are river water,
Use as a heat source, such as natural water such as lake water, groundwater, or spring water, or circulating water that circulates to other devices such as a ground heat exchanger, a sewage heat exchanger, or a waste heat recovery heat exchanger. Various water can be used as long as the water is possible.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS [First Embodiment] FIG. 1 shows a snow melting facility using a heat pump, 1 is a liquid heat exchanger for exchanging heat of a refrigerant R with a heat source side heat medium liquid Lb, and 2 is a refrigerant R A heat exchanger for exchanging heat with the atmospheric air A, 2a is a fan for passing air A to be heat-exchanged to the air heat exchanger 2,
Reference numeral 3 denotes a load heat exchanger for exchanging the refrigerant R with the load side heat transfer fluid Lf.

In the first embodiment, each of the heat source side heat transfer fluid Lb and the load side heat transfer liquid Lf is provided with brine (antifreeze).
Is used.

Reference numeral 4 denotes a compressor, 5 denotes an expansion valve, 6 denotes a refrigerant guide circuit in which four check valves 6a to 6d are combined in a bridge circuit, 7 denotes a receiver, and V1 to V3 denote first to third refrigerant paths. The third four-way valves V4 and V5 are first and second on-off valves for switching the refrigerant path, and the heat pump circuit (refrigeration circuit) includes these and the three heat exchangers 1, 2, and 3 as main constituent devices. ) H is formed.

Reference numerals 8A and 8B denote first and second heat-exchanging heat exchangers for exchanging the heat source side heat transfer fluid Lb with water W as a heat-extracting source, and 9 denotes these first and second heat-exchanging heat exchangers. Vessels 8A, 8B
Is a heat source side circulation path in which the heat source side heat transfer fluid Lb is circulated by the circulation pump 10 between each of the liquid heat exchangers 1 and 2.
Reference numeral 6 denotes a liquid-side three-way valve for switching between a state in which the heat source side heat transfer medium Lb is circulated through the first heat-exchange heat exchanger 8A and a state in which the heat-source-side heat medium liquid Lb is circulated through the second heat-exchange heat exchanger 8B. V8 is a water-side on-off valve for switching between a state in which water W as a heat collection source flows through the first heat collection heat exchanger 8A and a state in which water W flows through the second heat collection heat exchanger 8B. is there.

Reference numeral 11 denotes a snow melting heat exchanger as a load device for melting snow accretion at a snow melting target location using the load side heat transfer fluid Lf as a heat source, and 12 denotes the snow melting heat exchanger 11 and the load heat exchanger 3. And a load-side circulation path for circulating the load-side heat transfer fluid Lf by the circulation pump 13.

In the snow melting facility, the four-way valve V
The following operations (a) to (e) are selectively performed by switching the refrigerant paths by 1 to V3 and the on-off valves V4 and V5.

(A) Operation corresponding to load of air heat source In this operation, as shown in FIG. 2, in the heat pump circuit H, the refrigerant R is supplied to the compressor 4-first four-way valve V1-pair load heat exchanger 3-refrigerant guide circuit 6 -Receiver 7-Expansion valve 5-Refrigerant guide circuit 6-Second four-way valve V2-Air heat exchanger 2- First
The four-way valve V1-the third four-way valve V3-the compressor 4 are circulated in this order.

That is, the refrigerant circulation allows the heat exchanger for air 2 to function as the refrigerant evaporator E and the heat exchanger for load 3 to operate as the refrigerant condenser under the circulation operation of the load side heat transfer fluid Lf. In this manner, the load-side heat transfer fluid Lf sent to the snow melting heat exchanger 11 is heated in the form of collecting heat from the air A to melt snow.

(B) Operation corresponding to load of two heat sources (air → water) In this operation, in the heat pump circuit H, the refrigerant R is supplied to the compressor 4-first four-way valve V1-to-load heat exchanger 3 as shown in FIG. -Refrigerant guide circuit 6-receiver 7-expansion valve 5-refrigerant guide circuit 6-second four-way valve V2-air heat exchanger 2-first
The on-off valve V4-the liquid heat exchanger 1-the third four-way valve V3-the compressor 4 are circulated in this order.

That is, due to the circulation of the refrigerant, the air-to-air heat exchanger 2 and the liquid-to-liquid heat exchanger 1 are arranged in series in this order under the circulation operation of the heat source side heat transfer fluid Lb and the load side heat transfer liquid Lf. Both are made to function as the refrigerant evaporator E and the load heat exchanger 3 is made to function as the refrigerant condenser C, whereby the heat is taken from the air A and the water W, and the load side to be sent to the snow melting heat exchanger 11 The heating medium Lf is heated to melt snow.

(C) Operation corresponding to load of water heat source In this operation, as shown in FIG. 4, in the heat pump circuit H, the refrigerant R is supplied to the compressor 4-first four-way valve V1-to-load heat exchanger 3-refrigerant guide circuit 6 -Receiver 7-Expansion valve 5-Refrigerant guide circuit 6-Second four-way valve V2-Liquid heat exchanger 1-Third four-way valve V3-Compressor 4

That is, due to the circulation of the refrigerant, the liquid heat exchanger 1 functions as the refrigerant evaporator E under the circulation operation of the heat source side heat transfer fluid Lb and the load side heat transfer liquid Lf. The exchanger 3 functions as a refrigerant condenser C, and thereby heats the load-side heat medium liquid Lf sent to the snow melting heat exchanger 11 in a form of collecting heat from the water W to melt snow.

(D) Main defrosting operation In this operation, as shown in FIG. 5, in the heat pump circuit H, the refrigerant R is supplied to the compressor 4-first four-way valve V1-air heat exchanger 2-second on-off valve V5- The receiver 7-expansion valve 5-refrigerant guide circuit 6-second four-way valve V2-liquid heat exchanger 1-third four-way valve V3-compressor 4 is circulated in this order.

That is, by the circulation of the refrigerant, the liquid heat exchanger 1 functions as the refrigerant evaporator E and the air heat exchanger 2 functions as the refrigerant condenser under the circulation operation of the heat source side heat transfer fluid Lb. C, thereby performing defrosting of the air heat exchanger 2 in a form of collecting heat from the water W.

(E) Auxiliary defrosting operation In this operation, as shown in FIG. 6, in the heat pump circuit H, the refrigerant R is supplied to the compressor 4-first four-way valve V1-air heat exchanger 2-second four-way valve V2- Refrigerant guide circuit 6-receiver 7
-Expansion valve 5-refrigerant guide circuit 6-load heat exchanger 3-first
The four-way valve V1-the third four-way valve V3-the compressor 4 are circulated in this order.

That is, due to the circulation of the refrigerant, the load-side heat exchanger 3 functions as the refrigerant evaporator E and the air-side heat exchanger 2 condenses the refrigerant under the circulation operation of the load-side heat medium liquid Lf. The air heat exchanger 2 is defrosted in such a manner that the air heat exchanger 2 is functioned as a device C and heat is taken from the load side.

S1 is a sensor for detecting the temperature tw of the water W supplied to the heat collecting heat exchangers 8A and 8B, S2 is a sensor for detecting the temperature ta of the air A passing through the air heat exchanger 2,
S3 is a sensor for detecting the temperature tb of the heat-source-side heat transfer fluid Lb passed through the heat-exchanging heat exchangers 8A and 8B, and S4 is detecting the temperature tf of the load-side heat transfer fluid Lf passed through the snow-melting heat exchanger 11. The sensors S5 and S6 are the temperatures t1 and t of the water W sent from each of the first and second heat sampling heat exchangers 8A and 8B.
2 is a sensor for detecting

A controller 14 automatically selects and executes each of the above-mentioned operations based on the detected temperatures of the sensors S1 to S6. This controller 14 automatically controls the operations corresponding to the loads (a) to (c). As a selection, a state point P (tw, ta) using the water temperature tw and the air temperature ta detected by the sensors S1 and S2 as parameters is in a region K1 on a preset selection criterion D1 as shown in FIG. In the situation, the load corresponding operation of (a) in which heat is taken only from the air A is selected and executed, and in the situation where the state point P (tw, ta) is in the region K2, the air A
And the load corresponding operation of (b) in which heat is collected from both the water W and the state point P (tw, ta) is in the region K3, the load of (c) in which heat is collected only from the water W Select and execute the corresponding operation.

The controller 14 determines that a certain amount or more of frost has occurred in the air heat exchanger 2 during the load corresponding operation (a) or (b) involving heat collection from the air A. When it is detected by the frost detection means, the operation is automatically switched to the defrosting operation of (d) or (e), and the automatic selection of the defrosting operation of (d) or (e) is performed as (d)
The temperature tb of the heat source side heat transfer fluid Lb detected by the sensor S3 when the main defrosting operation is performed, and the temperature of the load side heat transfer fluid Lf detected by the sensor S4 during the execution of the auxiliary defrosting operation (e). State point Q (tb, tf) using tf as a parameter
However, in a situation where the temperature is in the region M1 on the preset selection criterion D2 as shown in FIG. 8, the main defrosting operation of (d) collecting heat from the water W is selected and executed, and the same state points Q (tb, tf) are obtained. ) Is in the region M2, the auxiliary defrosting operation of (e) for collecting heat from the load side is selectively executed.

When the state point Q (tb, tf) shifts to the area M2 during the execution of the main defrosting operation (d), the operation is switched to the auxiliary defrosting operation (e) accordingly. During the auxiliary defrosting operation (e), the state point Q (tb,
When the time tf) shifts to the area M1, the operation is switched to the main defrosting operation (d). Then, when the defrosting is completed, the defrosting operation of (d) or (e) is automatically terminated, and thereafter, the operation returns to the selection execution of the load corresponding operation of (a) to (c).

Further, the controller 14 detects the sensors S5 and S6 in the load corresponding operation (b) or (c) accompanied by heat extraction from the water W or in the main defrosting operation (d). The switching operation of the liquid-side two-way valve V6 and the water-side on-off valves V7 and V8 based on the temperatures t1 and t2 causes the heat source side heat transfer fluid Lb and the water W in the first and second heat-collecting heat exchangers 8A and 8B. Is passed through the inside of the vessel (that is, the one that actually functions as a heat exchanger) is changed to the water temperature t sent from the heat-collecting heat exchangers 8A and 8B in a state where the heat source side heat transfer fluid Lb and the water W pass.
Each time the temperature t1 or t2 decreases to the set lower limit temperature tx (temperature near freezing of water), the switching is automatically performed.

In FIG. 7, tas is a set threshold air temperature for determining whether or not to take heat from water W in a load corresponding operation.

In FIG. 8, tb1 and tb2 are the freezing dangerous temperature and freezing caution temperature set for the heat source side heat transfer fluid Lb, and tf1 and tf2 are the freezing dangerous temperature and freezing caution temperature set for the load side. In the automatic selection of the defrosting operation, the detected heat medium liquid temperatures tb and tf on the heat source side and the load side by the sensors S3 and S4 are both between the freezing dangerous temperature and the freezing caution temperature, and are both higher than the freezing caution temperature. In the situation described in (2), the main defrosting operation of (d) is selected and performed, and as a whole, the main defrosting operation of (d) and the auxiliary defrosting operation of (e) are performed. Driving is prioritized.

In the first embodiment, the first and second
In the alternate use of the heat collecting heat exchangers 8A and 8B, the passage of the water W to the inactive side heat collecting heat exchangers 8A and 8B is not completely blocked, and the inactive side heat collecting heat exchanger 8A is not used. , 8B
Also, by passing a small amount of water W, the recovery of the temperature of the heat-exchange heat exchangers 8A and 8B on the rest side is promoted.

As described above, in the first embodiment, the controller 1
4 indicates the temperature tb of the heat source side heat transfer fluid Lb and the load side when the defrosting operation for removing the frost formed on the air heat exchanger 2 in the execution of the load corresponding operation (a) or (b) is required. Heat medium liquid Lf
A defrost control unit that automatically selects and executes the main defrosting operation (d) and the auxiliary defrosting operation (e) according to the temperature tf of (i).

The controller 14 controls the liquid heat exchanger 1
(B), (c), and (d) (liquid heat source operation) in which the heat exchanger 3 functions as the refrigerant evaporator E and the heat exchanger 3 or the heat exchanger 2 for air functions as the refrigerant condenser C. In the plurality of heat collecting heat exchangers 8A and 8B for exchanging the heat source side heat medium liquid Lb with water W, the heat source side heat medium liquid Lb that passes through the heat source side heat medium liquid Lb and the water The antifreezing control means automatically switches according to the state of heat exchange with W.

In the snow melting facility of the first embodiment, in addition to the above-described operations (a) to (e), the following operations (f) to (h) can be selectively executed as necessary.

(F) Operation corresponding to load of two reverse heat sources (water → air) In this operation, in the heat pump circuit H, the refrigerant R is supplied to the compressor 4-first four-way valve V1-to-load heat exchanger 3-refrigerant guide circuit. 6-Receiver 7-Expansion valve 5-Refrigerant guide circuit 6-Second four-way valve V2-Liquid heat exchanger 1-Third four-way valve V3-Second
Four-way valve V2-to air heat exchanger 2-first four-way valve V1-third
Circulate in the order of the four-way valve V3-compressor 4.

That is, by this refrigerant circulation, the liquid heat exchanger 1 and the air heat exchanger 2 are arranged in series in this order under the circulation operation of the heat source side heat transfer fluid Lb and the load side heat transfer liquid Lf. Both function as a refrigerant evaporator E and the load heat exchanger 3 functions as a refrigerant condenser C.
In addition, the load-side heat transfer fluid Lf sent to the snow-melting heat exchanger 11 is heated in the form of collecting heat from the air A to melt snow.

(G) Combined operation for defrosting / loading In this operation, in the heat pump circuit H, the refrigerant R is supplied to the compressor 4-first four-way valve V1-air heat exchanger 2-second four-way valve V2-third. Four-way valve V3-first four-way valve V1-load heat exchanger 3-refrigerant guide circuit 6-receiver 7-expansion valve 5-refrigerant guide circuit 6-second four-way valve V2-liquid heat exchanger 1-third
Circulate in the order of the four-way valve V3-compressor 4.

That is, due to the circulation of the refrigerant, the liquid heat exchanger 1 functions as the refrigerant evaporator E under the circulation operation of the heat source side heat medium liquid Lb and the load side heat medium liquid Lf. The heat exchanger 3 and the heat exchanger 3 are arranged together in this order to function as a refrigerant condenser C.
In this mode, the load-side heat transfer fluid Lf sent to the snow melting heat exchanger 11 is heated to melt snow, and in parallel with this, defrosting of the air heat exchanger 2 is performed.

(H) Two heat source defrosting operation In this operation, in the heat pump circuit H, the refrigerant R is supplied to the compressor 4-first four-way valve V1-air heat exchanger 2-second four-way valve V2-refrigerant guide circuit 6 -Receiver 7-Expansion valve 5-Refrigerant guide circuit 6-Load heat exchanger 3-First four-way valve V1-Third four-way valve V3-Second four-way valve V2-Liquid heat exchanger 1-Third
Circulate in the order of the four-way valve V3-compressor 4.

That is, by the circulation of the refrigerant, the load heat exchanger 3 and the liquid heat exchanger 1 are arranged in series in this order under the circulation operation of the heat source side heat medium liquid Lb and the load side heat medium liquid Lf. Both function as a refrigerant evaporator E, and the air heat exchanger 2 functions as a refrigerant condenser C. Thereby, the defrosting of the air heat exchanger 2 is performed in a mode of collecting heat from the load side and the water W. Do.

Also, in the operations of (h) to (h), the control unit 14
Is the sensor S in the same manner as in (b), (c) and (d).
5 based on the detected temperatures t1 and t2 of S6.
Then, the automatic alternate use of the second heat collection heat exchangers 8A and 8B is performed.

[Second Embodiment] FIG. 9 shows another snow melting facility using a heat pump. The difference between the second embodiment and the first embodiment is that the liquid heat exchanger 1 has the first and second heat exchangers. A plurality of liquid heat exchangers 1A and 1B are provided, and water W as a heat source is directly used as a heat source side heat transfer fluid to be exchanged with the refrigerant R in the liquid heat exchanger 1 (1A, 1B). It is.

The parts having the same functions as those of the first embodiment are denoted by the same reference numerals as those used in the first embodiment.

V6 'transfers the refrigerant R to the first liquid heat exchanger 1A.
, V7 ′, V that switches between a state of passing through the second liquid heat exchanger 8B and a state of passing through the second liquid heat exchanger 8B
Reference numeral 8 'denotes a water-side opening / closing valve for switching between a state in which water W as a heat source is passed through the first liquid heat exchanger 1A and a state in which water W is passed through the second liquid heat exchanger 1B. .

S1 'is a sensor for detecting the temperature tw of the water W supplied to the liquid heat exchangers 1A and 1B, S5' and S5 '
Reference numeral 6 'denotes a sensor for detecting the temperatures t1' and t2 'of the water W sent from the first and second liquid heat exchangers 1A and 1B.

Reference numeral 14 'denotes a controller for automatically selecting and executing each of the above-mentioned operations (a) to (e) based on the temperature detected by each sensor. (C)
As in the first embodiment, the state point P (tw, t) using the water temperature tw and the air temperature ta detected by the sensors S1 'and S2 as parameters, as in the first embodiment.
a) is a region K1 to K1 on a selection criterion D1 as shown in FIG.
3, the operation corresponding to the load of (a) to (c) is selectively performed selectively.

The controller 14 'detects that a certain amount or more of frost has formed in the air heat exchanger 2 during the operation corresponding to the load (a) or (b) accompanied by heat collection from the air A. Is detected by the frost detection means, the operation is automatically switched to the defrosting operation of (d) or (e), and the sensor S1 is automatically selected as the defrosting operation of (d) or (e). And the state point Q ′ using the temperature tf of the load-side heat transfer fluid Lb detected by the sensor S4 in the execution of the auxiliary defrosting operation (e) as a parameter.
In a situation where (tw, tf) is in the region M1 'on the preset selection criterion D2' as shown in FIG. 10, the main defrosting operation of (d) for collecting heat from the water W is selected and executed. In a situation where the state point Q '(tw, tf) is in the region M2', the auxiliary defrosting operation of (e) for collecting heat from the load side is selectively executed.

As in the first embodiment, if the state point Q '(tw, tf) shifts to the area M2 during the execution of the main defrosting operation of (d), the auxiliary defrosting of (e) is accordingly performed. When the state point Q '(tw, tf) shifts to the area M1 during the auxiliary defrosting operation (e), the operation is switched to the main defrosting operation (d). Switch. Then, when the defrosting is completed, the defrosting operation of (d) or (e) is automatically terminated, and thereafter, the operation returns to the selection execution of the load corresponding operation of (a) to (c).

Further, in the controller 14 'for the load corresponding operation (b) or (c) involving the heat collection from the water W or the main defrosting operation (d), the sensors S5' and S6 are used. ′
Refrigerant two-way valve V6 'based on the detected temperatures t1' and t2 '
And the switching operation of the water-side on-off valves V7 'and V8'
Of the first and second liquid heat exchangers 1A and 1B, the one that allows the refrigerant R and the water W to pass through the inside of the chamber (that is, the one that actually functions as a heat exchanger) is set to the state where the refrigerant R and the water W pass. Outgoing water temperature t1 'from a certain liquid heat exchanger 1A, 1B,
Each time t2 'falls to the set lower limit temperature tx (temperature near freezing of water), the switching is automatically performed.

In FIG. 10, tw1 and tw2 are the freezing dangerous temperature and the freezing caution temperature set for the water W side, and tf.
1 and tf2 are the freezing dangerous temperature and the freezing caution temperature set for the load side.
Similarly to the embodiment, the detection temperature tw of the water W and the detection temperature tf of the load side heat transfer fluid Lf detected by the sensors S1 'and S4 are both between the freezing dangerous temperature and the freezing caution temperature, and both are the freezing caution temperature. In the situation described above, the main defrosting operation of (d) is selected and executed, so that the main defrosting operation of (d) and the auxiliary defrosting operation of (e) are performed as a whole. The frost operation is preferentially performed.

Also in the second embodiment, as in the first embodiment, in the alternate use of the first and second liquid heat exchangers 1A and 1B, the inactive liquid heat exchangers 1A and 1B are used.
The passage of the water W to B is not completely shut off, but a small amount of water W is also passed to the non-liquid heat exchangers 1A and 1B on the non-operating side, so that the non-liquid heat exchangers 1A and 1B on the non-operating side are cooled. It promotes temperature recovery.

As described above, the water W as a heat source is added to the heat source side heat transfer fluid to be exchanged with the refrigerant R in the liquid heat exchanger 1 (1A, 1B).
In the second embodiment in which the controller 14 'is used directly, the controller 14'
When the defrosting operation for removing the frost formed on the air heat exchanger 2 in the execution of the load corresponding operation (a) or (b) is necessary,
The main defrosting operation (d) and the auxiliary defrosting operation (e) are automatically selected and executed according to the temperature tw of the water W as the heat source side heat medium liquid and the temperature tf of the load side heat medium liquid Lf. It constitutes a defrost control means.

The controller 14 'causes the liquid heat exchanger 1 to function as a refrigerant evaporator E, and causes the load heat exchanger 3 or the air heat exchanger 2 to function as a refrigerant condenser C. In the operations (b), (c), and (d) (liquid heat source operation), one of the plurality of liquid heat exchangers 1A and 1B for exchanging the refrigerant R with the water W, the refrigerant R passing through the inside of the heat exchangers. The anti-freezing control means automatically switches according to the heat exchange state between the refrigerant R and the water W.

In the snow melting equipment of the second embodiment, similarly to the snow melting equipment of the first embodiment, in addition to the above-mentioned operations (a) to (e), if necessary, the above-mentioned (f) to (h) are used. ) Operation can be selected and performed, and the operations of (h) to (h) also involve the controller 1
Reference numeral 4 'denotes the first and second liquid heat exchangers 1A based on the detected temperatures t1' and t2 'of the sensors S5' and S6 'as in (b), (c) and (d). , 1B.

[Another Embodiment] Next, another embodiment will be described.

In the first embodiment, the detected temperature t of the heat-source-side heat transfer fluid Lb passed through the heat-exchanger heat exchangers 8A and 8B.
b, the automatic selection between the main defrosting operation and the auxiliary defrosting operation is performed based on the detected temperature tf of the load-side heat medium liquid Lf passed through the snow melting heat exchanger 11 as a load device. The temperature of the heat-source-side heat medium liquid Lb used to determine the automatic selection between the main defrosting operation and the auxiliary defrosting operation is the temperature of the heat-source-side heat medium liquid Lb sent from the heat collecting heat exchangers 8A and 8B. May be
Similarly, the temperature of the load-side heat transfer fluid Lf used for determining the automatic selection between the main defrosting operation and the auxiliary defrosting operation may be the temperature of the load-side heat transfer liquid Lf sent from the load device. .

In the second embodiment, the detected temperature tw of the water W passed through the liquid heat exchanger 1 (1A, 1B) as the heat source side heat transfer fluid, and the snow melting heat exchanger 11 as the load device Automatic selection between the main defrosting operation and the auxiliary defrosting operation is performed based on the detected temperature tf of the load-side heat transfer fluid Lf passed through the heat exchanger. In a mode in which water W is used as the heat-source-side heat transfer medium to be heated, the temperature of water W used to determine the automatic selection between the main defrosting operation and the auxiliary defrosting operation is sent from the liquid heat exchangers 1A and 1B. The temperature of the water W may be the same, and similarly, the temperature of the load-side heat transfer fluid Lf used to determine the automatic selection between the main defrosting operation and the auxiliary defrosting operation is also the load-side heat medium liquid Lf sent from the load device. The temperature of the medium Lf may be used.

The temperature of the heat-source-side heat transfer fluid Lb, W (including the case where water W is used directly as the heat-source-side heat transfer fluid) and the load-side heat transfer fluid L
The selection criterion used in the automatic selection between the main defrosting operation and the auxiliary defrosting operation based on the temperature of f prevents freezing trouble on the heat source side heat transfer fluids Lb and W and freezing trouble on the load side. Specifically, any type of selection criterion may be used as long as the selection function is provided.

When the selection criteria D2, D2 'as shown in FIGS. 8 and 10 are used, the heat source side heat transfer fluids Lb, W
The freezing dangerous temperatures tb1 and tw1 and the caution freezing temperatures tb2 and tw2 set for the side and the freezing dangerous temperature tf1 and the caution freezing temperature tf2 set for the load side are respectively used for the heat source side heat transfer fluids Lb and W, Load side heat transfer fluid Lf
Or the detection positions of the temperatures of the heat source side heat transfer fluids Lb and W and the load side heat transfer fluid Lf used to determine the automatic selection between the main defrosting operation and the auxiliary defrosting operation, and furthermore, the heat collection source type An appropriate value may be selected according to the design conditions of the device, such as the application of the load device and the like.

In the first embodiment, one of the first and second heat-exchanging heat exchangers 8A and 8B that allows the heat-source-side heat transfer fluid Lb to pass through the inside of the heat-exchanger is replaced with the heat-source-side heat transfer fluid Lb and water. In order to automatically switch in accordance with the state of heat exchange with W, the heat-collecting heat exchangers 8A, 8 in a state in which the heat source side heat transfer fluid Lb and the water W pass.
The switching is performed each time the temperature t1, t2 of the water discharged from B decreases to the set lower limit temperature tx. However, the heat source side heat transfer fluid Lb of the two or more heat collecting heat exchangers is used. As the specific state information of the heat exchange state between the heat source side heat transfer fluid Lb and the water W used for the determination of the automatic switching of the one that passes through the inside of the vessel, various kinds of information can be adopted.
The temperature difference between the heat-source-side heat transfer liquid Lb after passing through the heat-collecting heat exchangers 8A and 8B and the water W after passing through the inside of the heat-collecting heat exchangers 8A and 8B in a state where the heat-source-side heat transfer liquid Lb and water W pass. The switching may be performed every time it becomes smaller.

In the above-described second embodiment, one of the first and second liquid-to-liquid heat exchangers 1A and 1B that allows the refrigerant R to pass through the inside of the heat exchanger 1A and 1B is set in a heat exchange state between the refrigerant R and the water W. Automatically switched according to the temperature T1 ′, t1 of the water sent from the liquid heat exchangers 1A, 1B in the passing state of the refrigerant R and the water W.
The switching is performed every time 2 ′ falls to the set lower limit temperature tx. However, even in the case where water W is used as the heat source side heat transfer fluid for exchanging heat with the refrigerant R in the liquid heat exchangers 1A and 1B. Similarly, specific state information of the heat exchange state between the refrigerant R and the water W used for the determination of automatic switching of the two or more plural liquid heat exchangers that pass the refrigerant R inside the liquid heat exchanger is as follows. The temperature difference between the refrigerant R after passing through the inside of the liquid heat exchangers 1A and 1B and the water W after passing through the inside of the liquid heat exchangers 1A and 1B in a state where the refrigerant R and water W pass is larger than the set value. The switching may be performed each time is smaller.

Further, as described above, the heat collecting heat exchanger 8A,
8B is switched according to the heat exchange state between the heat source side heat transfer fluid Lb and the water W, or the liquid heat exchangers 1A and 1B are switched according to the heat exchange state between the refrigerant R and the water W. Alternatively, the switching of the heat exchanger for heat collection and the switching of the liquid heat exchanger may be performed at set time intervals.

Further, in implementing the invention according to claim 1, depending on the case, a mode may be adopted in which the automatic switching of the heat exchanger for heat collection and the automatic switching of the liquid heat exchanger are not performed as described above. .

The load-side heat transfer fluid Lf includes a heat-source-side heat transfer fluid Lb,
Like W, various liquids such as brine and water can be used,
Further, the application of the generated heat in the anti-load heat exchanger 3 is not limited to snow melting as described above, but may be any application such as prevention of freezing, heating or heating of articles.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing a first embodiment.

FIG. 2 is a diagram showing a flow of a refrigerant in a load operation of an air heat source.

FIG. 3 is a diagram illustrating a flow of a refrigerant in a load corresponding operation of two heat sources.

FIG. 4 is a diagram showing a flow of a refrigerant in a load operation of a water heat source.

FIG. 5 is a diagram showing a flow of a refrigerant in a main defrosting operation.

FIG. 6 is a diagram showing a flow of a refrigerant in an auxiliary defrosting operation.

FIG. 7 is a diagram showing selection criteria for load-adaptive operation.

FIG. 8 is a diagram showing selection criteria for a defrosting operation in the first embodiment.

FIG. 9 is a diagram illustrating a configuration of a second embodiment.

FIG. 10 is a diagram showing selection criteria for a defrosting operation in the second embodiment.

[Explanation of symbols]

 1, 1A, 1B Heat exchanger for liquid 2 Heat exchanger for air 3 Heat exchanger for load 8A, 8B Heat exchanger for heat collection 14, 14 'Defrosting control means, antifreezing control means A Air C refrigerant condenser E Refrigerant evaporator Lb Heat source side heat medium liquid Lf Load side heat medium liquid R Refrigerant tb, tw Heat source side heat medium liquid temperature tf Load side heat medium liquid temperature W Water, heat source side heat medium liquid

Claims (3)

[Claims] An air heat exchanger for exchanging heat between a refrigerant and atmospheric air, a liquid heat exchanger for exchanging heat between a refrigerant and a heat source liquid, and a pair for exchanging heat between the refrigerant and a load heat liquid. A load heat exchanger, wherein the air-to-air heat exchanger functions as a refrigerant evaporator, and the load-to-load heat exchanger functions as a refrigerant condenser. Function as an evaporator, and
A main defrosting operation in which the air heat exchanger functions as a refrigerant condenser; and an auxiliary defrosting function in which the load heat exchanger functions as a refrigerant evaporator, and the air heat exchanger functions as a refrigerant condenser. When the defrosting operation for removing the frost formed on the air heat exchanger by performing the load corresponding operation is necessary, the temperature of the heat source side heat transfer fluid and the load side heat can be switched. A heat pump device provided with defrost control means for automatically selecting and executing the main defrost operation and the auxiliary defrost operation according to the temperature of the medium. 2. A plurality of heat collecting heat exchangers for exchanging the heat source side heat transfer medium with water, wherein the liquid heat exchanger functions as a refrigerant evaporator, and
In the liquid heat source operation in which the heat-to-load heat exchanger or the air-to-air heat exchanger functions as a refrigerant condenser, one of the plurality of heat-collecting heat exchangers that allows the heat-source-side heat transfer medium to pass therethrough, The heat pump device according to claim 1, further comprising a freeze prevention control unit that automatically switches according to a heat exchange state between the heat source side heat transfer fluid and water or at set time intervals. 3. Using water as the heat source side heat transfer fluid, providing a plurality of the liquid heat exchangers, making the liquid heat exchanger function as a refrigerant evaporator, and
In the liquid heat source operation in which the load-to-load heat exchanger or the air-to-air heat exchanger functions as a refrigerant condenser, one of the plurality of liquid-to-liquid heat exchangers that allows the refrigerant to pass through the inside of the heat exchanger is used for heat transfer between the refrigerant and water. 2. The heat pump device according to claim 1, further comprising a freeze prevention control unit that automatically switches according to a replacement state or at set time intervals.