JPH0223793B2 - - Google Patents

Description

[Detailed description of the invention] The present invention relates to a heat pump type heater.

Conventionally used air source heat pump air conditioners have an indoor unit with a fan, a fan motor, a fin-and-tube heat exchanger, a control unit, etc., and an outdoor unit with a compressor, fan, and fan. It has a motor, a fin-and-tube heat exchanger, a four-way switching valve, etc. By switching the four-way switching valve, the refrigerant circuit is switched to perform cooling operation, heating operation, or defrosting of the outdoor heat exchanger. .

However, such heat pump type heaters have the following drawbacks. In other words, (1) For applications that do not require air conditioning, such as in cold regions, extra parts such as a four-way switching valve are included, resulting in a high price.

(2) Because the heavy compressor and the heat exchanger, which require ventilation, are housed in the same box of the outdoor unit, there are installation restrictions. For example, when storing the outdoor unit under the floor, ventilation is required. When installing an outdoor unit on the outside wall of a house, the outside wall may need special reinforcement to withstand the weight.

(3) Since both the indoor and outdoor units have fans and fan motors, electrical input is required to operate them, which reduces the energy efficiency of the heat pump.

(4) Since both the indoor and outdoor units have fan motors, it is necessary to connect electric wires between the units, which requires extra electrical work.

(5) Noise is generated because both the indoor and outdoor units have fans.

(6) During heating, the indoor unit blows the indoor air indoors using a fan after heating, but when this air hits the human body, it causes discomfort.

(7) Indoor units are usually floor-standing or wall-mounted, but both occupy the floor or wall and exist as foreign objects in the room, which imposes constraints on both space and aesthetics.

(8) The refrigerant flow noise caused by switching the four-way switching valve during defrosting creates noise, making it unsuitable for use in bedrooms, etc.

The present invention was proposed in view of these circumstances, and conventional air source heat pumps use electricity as driving energy, and in addition to advantages such as safety, cleanliness, and ease of operation, they have advantages compared to simple electric heaters. Since the heating efficiency is 2 to 5 times higher, the purpose of the present invention is to provide a heat pump type heater that is inexpensive, energy-saving, and has excellent comfort, taking advantage of this advantage and eliminating the above-mentioned disadvantages. A heat pump type heating system in which an air source heat pump type heater is divided into three units: an indoor unit 3, an outdoor unit 1, and a compressor unit 2, with the indoor unit 3 being a panel type and the outdoor unit 1 being a natural convection type. In this machine, the outdoor unit 1 is configured with a natural convection heat exchanger having wire-like fins 13 that are perpendicular to the ground and have a circular cross section, and a part of the liquid refrigerant condensed in the indoor unit 3 is It is characterized by being provided with a bypass valve 24 that opens and closes depending on the temperature of the compressor discharge pipe, a throttle 27, and a bypass return circuit 204 that returns the refrigerant gas from the compressor 21 to the compressor 21 through a heat exchange section 25. do.

An embodiment of the present invention will be explained with reference to the drawings.
Figure 1 is a side view showing the installation situation in the house, Figure 2 is the system diagram in Figure 1, Figure 3 is a perspective view of the outdoor unit in Figure 1, and Figure 4 is the indoor unit in Figure 1. Fig. 5 is a perspective view showing the - of Fig. 4.
FIG. 6 is a cross-sectional view showing the frosted state of the fin in FIG. 3.

First, in Fig. 1, 1 is an outdoor unit,
It is installed on the wall 62 of the house. 2 is a compressor unit, which is housed under the floor 63. Reference numeral 3 designates an indoor unit, which is placed on the floor 63 and is used for indoor heating.
Between the indoor units 3, refrigerant pipes 51, 52,
53 and 54 are connected. Reference numeral 4 denotes a control operation box, which is connected to the compressor unit 2 through wiring 41.

Next, in FIGS. 2 to 5, the outdoor unit 1 is connected in parallel with a plurality of pipes 12 meandering between pipes 11 and 14, and is attached to a wall 62 by support legs 15, and the pipes 12 are equipped with heat exchange performance. A large number of wire-like fins 13 having a circular cross section are attached in a direction perpendicular to the gravity to perform natural convection heat exchange with the outdoor air. The compressor unit 2 includes a suction pipe 201 and a compressor 2
1. Discharge pipe 202, temperature sensing section 26 attached to discharge pipe 202, liquid pipe 203, throttle 22 inserted into liquid pipe 203, and bypass pipe 20 that bypasses this
5, bypass valve 23, compressor 21 from liquid pipe 203
It consists of a bypass return pipe 204, a bypass valve 24, a throttle 27, a heat exchanger 25 for exchanging heat between the bypass return pipe 204 and the discharge pipe 202, and the like.

The indoor unit 3 is panel-shaped, and constitutes a refrigerant circuit by an outgoing pipe 31, a return pipe 32, and many passages 33 that communicate these in parallel. Although it is formed as a space between the refrigerant and the plate 34, if the refrigerant pressure is high and there is a problem with pressure resistance, a pipe may be inserted into this space and the inside of the pipe may be used as a refrigerant passage. Reference numeral 36 denotes a top sheet made of plastic, cloth, or the like, which not only protects the heat sink 34 and improves its texture, but also has a certain degree of heat insulating and heat storage properties, thereby mitigating temperature changes in the heat sink 34. 37 is a heat insulating material that prevents heat loss and also moderates temperature changes due to its heat storage properties.

In such a device, (1) First, to explain the normal heating cycle, refrigerant gas compressed by the compressor 21 enters the indoor unit 3 through the discharge pipe 202 and piping 53, as shown by the solid arrow. , enters the passage 33 from the outbound pipe 31, radiates heat into the room from the heat sink 34,
By heating the room, it condenses and becomes a liquid refrigerant, which flows from the return pipe 32 to the pipe 54 and the liquid pipe 203.
, the pressure is reduced by the restrictor 22, the flow becomes a low-pressure liquid-gas mixed flow, passes through the piping 52, enters the outdoor unit 1, and then enters the piping 1 inside the outdoor unit 1.
1, enters the pipe 12, exchanges heat with outdoor air and evaporates to become a low-pressure refrigerant gas, passes from the pipe 14 to the pipe 51, returns to the compressor unit 2, is sucked into the compressor 21 through the suction pipe 201, and starts the heating cycle. Do this.

(2) In this process, for example, when the outdoor temperature is high and the indoor unit 3 is also relatively high temperature, and you want to perform heating, the refrigerant pressure increases, the discharge gas temperature rises, and the surface sheet 3
6. The temperature of the upper surface may rise above the allowable value, causing discomfort to the human body that comes into direct contact with it, or causing distortion of the furniture placed above it. In such a case, the temperature sensor 26 may cause the discharge pipe 2 to
02 temperature is detected and the bypass valve 24 is opened based on the signal, the liquid refrigerant in the liquid pipe 203 passes through the bypass return pipe 204, is depressurized by the throttle 27, becomes low temperature, and is transferred to the discharge pipe 202 by the heat exchanger 25.
After cooling the refrigerant gas inside, it returns to the compressor 21 or suction pipe 201 (only the case of returning to the compressor is shown in Figure 2). In the case of a reciprocating compressor, the air returns directly to the dome, and in the case of a rotary type compressor, where the pressure inside the dome is high, a hole is made in the internal low-pressure piping or cylinder so that the air returns directly to the cylinder. Therefore, the discharge pipe 20
In addition to being directly cooled, the refrigerant mixed with liquid gas returns to the compressor to lower the compressor temperature and the discharge gas temperature, thereby lowering the refrigerant gas temperature in the going pipe 31.

(3) During the heating process, if the outdoor temperature is relatively low and the humidity is high, frost 16 will form on the fins 13 of the outdoor unit 1 as shown in FIG.
Since frost 16 has a lower thermal conductivity than metal, it becomes a thermal resistor, and the surface temperature of the frost is higher than the surface temperature of the fins, and the relationship is as follows: fin surface temperature < frost surface temperature < outdoor air temperature.

Generally, the rate of frost deposition increases as the temperature difference between the frost and the air temperature increases, so the rate of frost deposition slows down as frost progresses. On the other hand, Finn 13
is wire-shaped and has a circular or near-circular cross section, so the surface area of the frost during frost formation as shown in the figure increases greatly compared to the surface area of the fins, and the amount of heat exchange = heat Since the equation is transmissibility x surface area x temperature difference between frost and air, the decrease in temperature difference is compensated for by increase in surface area, and even if frost forms, the amount of heat exchange does not necessarily decrease.

(4) In this way, frosting progresses slowly in the outdoor unit and there is little deterioration in performance, but in the case of adverse conditions such as sleet or snow, frosting progresses until each fin is no longer independent. Performance decreases significantly.
In this case, by opening the bypass valve 23 in FIG. 2, the high temperature refrigerant in the liquid pipe 203 is
As shown by the dashed arrow, bypass 203
→23→205→203→52→11→12→
14 to melt the frost. Since the fins 13 are wires extending perpendicularly to the ground as described above, the frost and ice slide down due to some heating, and the frost melting ends in a short time.

According to such a device, the following effects can be achieved.

(1) Since the compressor unit 2 is separated and does not contain a fan or electrical components, both the indoor unit 3 and the outdoor unit 1 are extremely thin, requiring less installation space, looking good, and requiring less wiring between them. construction is easy.

(2) Since the compressor unit 2 does not require special ventilation, it can be installed under the floor, underground, inside walls, etc., making it easy to obtain installation space. It is possible to tightly enclose it to prevent noise, and it can be installed in a location such as under the floor where it will not be a problem even if noise occurs, resulting in an extremely low-noise heater as a whole.

(3) Since no fan power is required, a heater with low energy consumption can be obtained.

(4) Since the indoor unit 3 not only heats the air, but also exerts a heating effect on the human body through contact or radiation, extremely comfortable heating can be obtained.

(5) Since it is an air source type heat pump heating that takes heat from outdoor air, it has a heating capacity of 2 to 5 times the electric input, and in combination with the above item (3), a heating system with extremely low operating costs can be obtained. .

(6) Since the fins of the outdoor unit are wire-shaped,
As mentioned above, since there is little deterioration in heat exchange performance due to frost formation and the progress of frost formation is slow, the time interval between frost melting becomes very long, and overall there is little decrease in heating capacity due to frost formation.

(7) When defrosting is required, it is done by opening the bypass valve 23, so compared to the usual method of circulating the refrigerant in the opposite direction using a four-way switching valve and performing cooling operation to defrost, it is possible to defrost from all directions. There is no need for a valve, so cold refrigerant flows through the indoor unit without causing discomfort or condensation, and the four-way switching valve does not generate noise, and the fins are vertical and wire-shaped, making it easy to defrost. .

(8) If the temperature of the discharged gas becomes too high, the valve 24 is opened and the temperature is lowered by cooling in the heat exchanger 25 and returning the liquid to the compressor, thereby reducing discomfort, burns, and There is no risk of deforming indoor items.

(9) Conventionally, both indoor and outdoor units do not have forced ventilation through their heat exchangers, so the heat transfer coefficient on the surface is low.
As the area of the heat exchanger increases, the amount of refrigerant in the pipes increases, exceeding the allowable capacity of the compressor and causing malfunctions. However, in the device of the present invention, the refrigerant passages are multi-circuit both indoors and outdoors, so one circuit Each circuit is shorter than the previous one, and even if the cross-sectional area of the refrigerant passage is made smaller, the refrigerant pressure drop will not increase.
Therefore, the volume of the refrigerant passage becomes small, and the required amount of refrigerant is reduced.

In the above embodiment, the indoor unit was installed on the floor, but it is also possible to attach legs to the indoor unit and stand it vertically on the floor, or to install it with a gap in the wall. Since it does not come into direct contact with the human body, furniture, floors, etc., the top sheet 36 and the heat insulating material 3
7, or the bypass return pipe 204, heat exchanger 25, temperature sensing section 26, etc. are not necessarily required. In addition, the bypass pipe 205 for defrosting can be used not only when only the throttle 22 is bypassed, but also when the discharge pipe 205 is configured to bypass both the throttle 22 and the indoor unit 3.
02 can also be connected downstream of the aperture 22.

In short, according to the present invention, the air source heat pump type heater is connected to the indoor unit 3, the outdoor unit 1,
In a heat pump type heater which is divided into three units including a compressor unit 2, the indoor unit 3 is a panel type, and the outdoor unit 1 is a natural convection type, the outdoor unit 1 is arranged in a direction perpendicular to the ground. , and a wire-like fin 1 with a circular cross section.
3, and a bypass valve 2 that opens and closes a portion of the liquid refrigerant condensed in the indoor unit 3 according to the temperature of the compressor discharge pipe.
4. By providing a bypass return circuit 204 that returns to the compressor 21 through the aperture 27 and the heat exchange section 25 with the refrigerant gas discharged from the compressor 21, an inexpensive, energy-saving, and high-performance heat pump type heater is obtained. Therefore, the present invention is extremely useful industrially.

[Brief explanation of drawings]

Fig. 1 is a side view showing an installation situation in a house showing one embodiment of the present invention, Fig. 2 is a system diagram of Fig. 1, Fig. 3 is a perspective view showing the outdoor unit of Fig. 1, and Fig. 4 1 is a perspective view showing the indoor unit of FIG. 1, FIG. 5 is a sectional view taken along the line - in FIG. 4, and FIG. 6 is a sectional view showing the frosted state of the fins of FIG. 3. 1...Outdoor unit, 2...Compressor unit, 3...
Indoor unit, 4...Control operation box, 11...Piping, 1
2... Pipe, 13... Fin, 14... Piping, 15... Support leg, 16... Frost, 21... Compressor, 22... Throttle, 23
... bypass valve, 24 ... bypass valve, 25 ... heat exchanger, 26 ... temperature sensing section, 27 ... throttle, 31 ... going pipe,
32... Return pipe, 33... Refrigerant passage, 34... Heat sink,
35...Back plate, 36...Top sheet, 37...Insulating material,
41... Wiring, 51, 52, 53, 54... Piping, 6
2... Wall, 63... Floor, 201... Suction pipe, 202... Discharge pipe, 203... Liquid pipe, 204... Bypass return pipe,
205...Bypass pipe.

Claims (1)

[Claims] 1 An air source heat pump type heater is divided into three units: an indoor unit 3, an outdoor unit 1, and a compressor unit 2. The indoor unit 3 is a panel type, and the outdoor unit 1 is a natural convection type heat pump type. In the heater, the outdoor unit 1 is configured with a natural convection heat exchanger having wire-like fins 13 that are perpendicular to the ground and have a circular cross section, and a part of the liquid refrigerant condensed in the indoor unit 3 is used. A bypass valve 24 that opens and closes the refrigerant gas according to the temperature of the compressor discharge pipe, a throttle 27, and a bypass return circuit 204 that returns the refrigerant gas to the compressor 21 through a heat exchange section 25 with the refrigerant gas discharged from the compressor 21. A heat pump type heater.