JPH02298761A - Refrigerating cycle for heat pump - Google Patents

Abstract

PURPOSE:To obtain a refrigerating cycle of a heat pump having excellent comfortability and efficiency by providing solenoid valves at an inlet tube connected to a pipe between an indoor heat exchanger and a throttle unit and opened within an accumulator, and an outlet tube opened within the accumulator and connected to a suction pipe to a compressor. CONSTITUTION:Solenoid valves 14, 15 are respectively provided at an inlet tube 16 connected to a pipe 18 between an indoor heat exchanger 3 and a capillary tube 5 and opened within an accumulator 9, and an outlet tube 17 opened within the accumulator 9 and connected to a suction pipe 19 to a compressor 1. As a result, when the compressor 1 is started, refrigerant stored in the lower part of the accumulator 9 is guided to a heat exchanger 13 of a bypass pipe 11 for high temperature refrigerant gas to be discharged from the compressor 11, overheated, and extracted from the accumulator 9 via the tube 17. The refrigerant gas is guided to the suction side of the compressor 1, recovered to the accumulator 9 as liquid refrigerant from the tube 16 after a refrigerating cycle is started, and high pressure of the refrigerant gas from the compressor 1 can be abruptly raised.

Description

[Detailed description of the invention] [Industrial use valve W! ]

The present invention relates to a refrigeration cycle for a heat pump used in an air conditioner.

[Conventional technology]

FIG. 3 is a refrigerant system diagram of a refrigeration cycle of a heat pump used in a conventional air conditioner disclosed in, for example, Japanese Utility Model Application No. 63-150258, and FIG. 4 is a block diagram showing the control configuration of FIG. 3. . In Figure 3, 1 is a pressure of 11am,
2 is a four-way valve, 3 is an indoor heat exchanger, 4 is a check valve, 5 is a capillary tube installed in parallel with the check valve 4, 6 is a check valve, 7 is a capillary tube installed in parallel with the reverse ratio valve 6, 8 is an outdoor heat exchanger, 9 is an accumulator, and these are connected in a ring by piping to constitute a refrigeration cycle. Next, the operation of this refrigeration cycle will be explained. The housing temperature of the compressor 1 is detected, and the outside air temperature is also detected, and the stagnation status of the liquid refrigerant is determined from these detected values. Based on this judgment, the frequency pattern when the compressor 1 is started is determined. This is to avoid that if the frequency at the time of starting the compressor 1 is accelerated when a large amount of liquid refrigerant is lying in the housing before starting the compressor 1, low pressure will be drawn in and the start-up speed will be delayed. It's for a reason.

[Problem to be solved by the invention]

The refrigeration cycle of the conventional air-conditioning P1-pump is configured as described above, so the frequency of the compressor cannot be rapidly increased during rapid heating. There was a problem that the hot air blowing time was delayed. This invention was made in order to solve the above-mentioned problems. It is possible to operate the compressor even if it suddenly accelerates to the maximum frequency at once when starting up the compressor, and it does not reduce the drawdown of low pressure, and can maintain high pressure. The objective is to obtain a heat pump refrigeration system that can quickly raise the pressure, quickly blow out hot air, and is highly comfortable and efficient.

[Means to solve the problem]

In the heat pump refrigeration cycle according to the present invention, one end is connected to the discharge pipe between the discharge port of the compressor and the four-way valve via the three-way valve, and the three-way valve and the four-way valve of the discharge pipe are connected to each other. A heat exchanger is installed in the bypass pipe whose end is connected, and this heat exchanger is installed in the 7 accumulator, and one end is connected to the piping between the indoor heat exchanger and the throttling device, and the other end opens into the accumulator. A solenoid valve is provided in each of the inflow pipe and the outflow pipe, which opens into the accumulator at one end and connects to the suction pipe to the compressor at the other end.

[Effect]

The refrigeration cycle in this invention (when starting the compressor,
The liquid refrigerant stored in the lower part of the accumulator is expelled from the accumulator through the outflow pipe by superheating the high-temperature refrigerant gas discharged from the compressor by guiding it to the heat exchanger in the bypass pipe. After the refrigerant gas is guided to the suction side of the compressor and the refrigeration cycle is started up, the refrigerant is collected as a liquid from the inflow pipe into the accumulator, and the high pressure of the refrigerant gas discharged from the compressor can be rapidly raised. [Embodiment] An embodiment of the present invention will be described below with reference to FIG. In Figure 1, 1 is a compressor, 2 is a four-way valve, 3 is an indoor heat exchanger, 5 is a capillary tube which is a throttling device, and 8 is an indoor heat exchanger, and each of the above parts is connected in a ring by piping. has been done. 9 is an accumulator, 10 is a three-way valve, and 11 is a bypass pipe. One end of the bypass pipe 11 is connected to the discharge pipe 12 between the discharge port of pressure ma1 and the four-way valve 2 via the three-way valve 10, and the bypass pipe Heat exchanger installed in the middle of 11 @13
is arranged at the lower part of the accumulator 9, and the bypass pipe 1
The other end of the discharge pipe 12 is connected between the three-way valve 10 and the four-way valve 2 of the discharge pipe 12. Further, 14 and 15 are inflow pipes 16. The first pipes provided in the middle of the outflow pipes 17, respectively. It is a second solenoid valve, and one end of the inflow w16 is connected to the pipe 18 between the indoor heat exchange @3 and the capillary tube 5, the other end is opened to the upper part of the accumulator 9, and the outflow 'll' 17 has one end opened in the upper part of the accumulator 9, and the other end is the suction pipe 1 between the four-way valve 2 and the suction port of the compressor 1.
9 is connected. 20 is a pressure sensor, 21 is a temperature sensor, and these sensors 20 and 21 are indoor heat exchangers y!
, is disposed closer to the connection part of the inlet pipe 16 of the pipe 18 between the vessel 3 and the capillary tube 5, and closer to the indoor heat exchanger 3 than this. Next, the operation of this embodiment will be explained. During heating operation, the three-way valve 10 closes the bypass pipe 1 when the compressor 1 starts.
1, the high-temperature, high-pressure refrigerant gas discharged from the compressor [1 is sent from the upstream section 11a of the bypass pipe 11 to the heat exchanger 13, where it exchanges heat with the refrigerant liquid stored in the lower part of the accumulator 9, This is gasified by heating. The refrigerant gas leaving the heat exchanger 13 has its enthalpy slightly lowered and the downstream portion 11bG of the bypass pipe 11! After that, it passes through the four-way valve 2 and is sent to the indoor heat exchanger N3, where it exchanges heat and heats the room (
ζ Provided, condensed and liquefied. The condensed and liquefied refrigerant is
The pressure is reduced in the capillary tube 5 and sent to the outdoor heat exchanger Wj8, where it is evaporated and vaporized, passes through the four-way valve 2, and is sucked into the compressor 1. On the other hand, the first solenoid valve 14 provided in the inflow pipe 16 is closed, the second solenoid valve 15 provided in the outflow pipe 17 is opened, and the refrigerant gas in the accumulator 9 is compressed through the outflow w17.
11, and the pressure inside the accumulator 9 is made low. For this reason, the gasification of the refrigerant liquid in the accumulator 9 is promoted, and as described above, it is heated by the high temperature and high pressure refrigerant gas passing through the heat exchanger 13 in the accumulator 9, and further gasification progresses partially. An excessive amount of refrigerant gas is sucked into the pressure wI machine 1 and supplied into the refrigeration cycle. After the compressor 1 is started, the refrigeration cycle starts up and becomes stable, and the second solenoid valve 15 is closed.
Switch the three-way valve 10 to the four-way valve 2 side. by this,
The release of refrigerant gas by the outflow W17 from inside the accumulator 9 is stopped, and the high temperature and high pressure refrigerant gas discharged from the compressor 1 stops flowing into the heat exchanger 13 installed in the bypass pipe 1, and the inside of the accumulator 9 is stopped. Gasification of the refrigerant liquid is also stopped. In addition, in the state B, the refrigerant gas discharged from the compressor 1 is sent directly to the four-way valve 2, and is then guided to the indoor heat exchanger 3. Furthermore, when the refrigeration cycle starts up sufficiently, there is an excess of refrigerant in this cycle, so supercooling progresses at the outlet of the indoor heat exchanger 3. Detect and
A detection signal from a control device (not shown) is input, the first electromagnetic valve 14 is opened in response to a command from the control device, and a part of the refrigerant condensed in the indoor heat exchanger 3 is recovered into the accumulator 9 through the inflow pipe 16. and maintain the appropriate amount of refrigerant in the refrigeration cycle. Furthermore, Fig. 2 shows experimental data representing the results of measuring the transient distribution of refrigerant at the start of the refrigeration cycle in a conventional refrigeration cycle without an accumulator according to the present invention in order to arrive at this invention. This invention was then made. In this invention, instead of the capillary tube in the above-described embodiment, the throttling device has two sets of throttling devices in which a check valve and a capillary tube are arranged in parallel, as shown in the conventional example shown in FIG. It may also be provided in the piping between the exchanger and the exchanger. [Effects of the Invention] As explained above, according to the present invention, when there is a shortage of refrigerant circulating in the system, such as when starting a refrigeration cycle, refrigerant gas is actively replenished, and the refrigerant circulating in the system is It is equipped with an accumulator that collects the excess refrigerant when there is excess, and a control function 611 for this accumulator.
Optimum refrigerant distribution can be achieved even during the startup transition during heating operation, and the effect is that a top pump refrigeration cycle with excellent comfort and efficiency can be obtained.

[Brief explanation of the drawing]

Fig. 1 is a refrigerant system diagram showing a refrigeration cycle of a heat pump according to an embodiment of the present invention, Fig. 2 is a diagram of experimental data showing the transient distribution of refrigerant from startup, and Fig. 3 is a refrigeration cycle of a conventional heat pump. Fig. 4 is a refrigerant system diagram showing f! of the refrigeration cycle shown in Fig. 3. FIG. 2 is a block diagram showing the configuration of ilJ. 1. - Compressor, 2. Four-way valve, 3. Indoor heat exchanger, 5.
Capillary tube (throttle device), 8... Outdoor heat exchanger, 9 Accumulator, 10... Three-way valve, 11 ・Bypass piping, 1
2 Discharge piping, 13... Heat exchanger, 14゜15 g4 magnetic valve, 16... Inflow piping, 17 - Outflow piping, 18 - Piping, 19... Suction piping, 20 Pressure sensor, 21 Temperature sensor. Note that the same reference numerals in the figures indicate the same or equivalent parts.

Claims (1)

[Claims] In a heat pump refrigeration cycle in which a compressor, a four-way valve, an indoor heat exchanger, a throttle device, and an outdoor heat exchanger are connected in a ring through piping, one end of the discharge piping between the compressor discharge port and the four-way valve is A heat exchanger is provided in a bypass pipe connected via a valve and whose other end is connected between the three-way valve and the four-way valve of the discharge pipe, and this heat exchanger is installed in an accumulator, and the indoor heat exchanger an inflow pipe having one end connected to a pipe between the and the throttle device and the other end opening into the accumulator; and an outflow pipe having one end opening into the accumulator and the other end connecting to the suction pipe to the compressor. A heat pump refrigeration cycle characterized by each having a solenoid valve.