JPS59150263A - Multi-chanber type heat pump system air conditioner - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a load detection arrangement for determining compressor frequency operation of a multi-chamber heat pump air conditioner.

Conventional configuration and its problems Conventionally, in multi-room air conditioners in which multiple indoor units are connected to one outdoor unit, a compressor is installed in the outdoor unit, and this compressor operates at a constant speed. It is operated at a rotation speed of 1, but a pole conversion method is used. The former constant speed type does not change the compressor capacity itself, so the input does not change depending on the number of units in multi-room operation, and when operating with a small number of indoor units, it changes due to bypassing excess refrigerant circulation, etc. , it has the disadvantage of poor EER (consumption efficiency). In addition, the latter method by changing the number of poles is a two-step switching method from 4-pole operation to 2-pole operation, and is better than the constant speed method because it can reduce the input to about half when a small number of machines are operated.
ER is getting better.

As shown in Figures 1 and 2, this pole number conversion method uses a pressure switch to detect the discharge pressure during heating (Figure 1) and the suction pressure during cooling (Figure 2), and then , from 2 poles to 4 poles, from 4 poles to 2 poles, and so on.

However, in this system, the capacity change is about twice that between 2-pole and 4-pole, and when the load is in between, for example, 75%, it will be operated with either 2-pole or 4-pole. They either lacked capacity or had excessive capacity, and had the disadvantage that they could not respond accurately to the load no matter which way they were operated.

OBJECTS OF THE INVENTION The present invention solves the above-mentioned conventional drawbacks, and provides a more accurate load detection configuration for determining the compressor operating frequency in a compressor that performs inverter control such as frequency change. With the goal.

Structure of the Invention The compressor is controlled via an electric signal converter that electrically converts pressure by a permanent magnet attached to the bellows and a magnetoresistive conversion element provided near the permanent magnet. is connected to the refrigeration cycle through a thin tube to detect the discharge pressure during heating and to detect the suction pipe pressure during cooling.

DESCRIPTION OF THE EMBODIMENTS One embodiment of the present invention will be described below with reference to FIGS. 3 to 6.

In one outdoor unit, 1 is a compressor, 2 is a four-way valve, and 3 is a compressor.
is an outdoor heat exchanger, 4 is an expansion valve for heating, 5 is a check valve for cooling, 6 is a liquid receiver, 7 is a three-way valve on the source side, 8 and 9 are solenoid valves on the source side, and 10.11 is a cooling valve. 12.13 is the check valve for heating, 14.16 is the indoor heat exchanger, 16.17 is the gas side solenoid valve, 18 is the gas side three-way valve, 19I′i accumulator, 20 is the bellows A bellows 21 is provided in the housing, and a heating thin tube 22 is installed on one side of the connecting tube 22.
a, and in the middle there is a solenoid valve 23 that opens during heating.

The end thereof is connected to a pipe 24 which becomes high pressure during heating. Further, on the other side of the connecting pipe 22, a cooling thin pipe 22b and a solenoid valve 25 which is opened during cooling are provided in the middle thereof, and the end thereof is connected to the suction pipe 26 whose pressure is low during cooling (same as during heating). ing. In bellows 21, 27 is bellows 2
1 is a permanent magnet attached, 28 is a magnetoresistance conversion element,
A permanent magnet 27 is installed on a printed circuit board 29 equipped with electronic control, and when the bellows 21 expands and contracts due to pressure, the permanent magnet 27
simultaneously moves left and right, and at that time, the magnetoresistive conversion element 28
, the resistance value changes, is calculated on the printed circuit board 29, and converted into an electrical signal.

A lead wire 30 is connected to an electric signal converter 31, and the electric signal converter 31 controls the frequency conversion of the compressor 1 (FIG. 1) using an inverter.

In the above configuration, during heating operation, when the heating load increases, the discharge pressure tends to decrease, and when the heating load decreases, the discharge pressure tends to increase; during cooling operation, when the cooling load increases, the suction pressure increases, and the cooling load As the value decreases, the suction pressure tends to decrease. Therefore, during heating, solenoid valve 2
3 is left open, and the heating thin tube 22a is connected to the piping 24 which becomes a discharge pipe during heating, so the bellows 21 is opened by continuously detecting the pressure depending on the magnitude of the load during heating.
As the permanent magnet 27 moves, the resistance value of the magnetoresistive conversion element 28 changes, and the electric signal converter 31 causes the pressure to fall within a certain range as shown in FIG. 4 during heating. In order to control the compression function, 1. It is possible to extract the compression function force corresponding to the valve load. This also applies during cooling; the solenoid valve 26 is opened during cooling, and the cooling thin tube 22b is connected to the suction pipe 26, so the suction pipe changes depending on the load during cooling. By continuously detecting the pressure, the bellows 21 expands and contracts, and the movement of the permanent magnet 27 changes the resistance value of the magnetoresistive conversion element 28, and the electric signal converter 31 converts the resistance value as shown in FIG. 6 during cooling. In addition, it is possible to control the compression force so that the pressure falls within a certain range, and extract the compression force corresponding to the load. That is, bellows 21, permanent magnet 2
7. The magnetoresistive conversion element 28 is a pressure sensor that converts changes in discharge pressure during heating and changes in suction pressure during cooling into continuous electrical signal changes. As shown in FIGS. 4 and 6, the compressor is controlled over a wide range to achieve optimum load operation.

Effects of the Invention As described above, the present invention provides a bellows that detects discharge pressure during heating and detects suction pipe pressure during cooling, a permanent magnet attached to this bellows, and a magnetoresistive conversion element near the permanent magnet. is installed to continuously detect the discharge pressure during heating and the suction pipe pressure during cooling, and use an electric signal converter to control the compressor over a wide range of frequency conversion using an inverter. , takes full advantage of the continuously variable capacity of the invar, and is capable of refrigerating the refrigeration cycle (cooling).
The cycle that corresponds to the load can be operated stably, monthly, and economically during both the heat pump cycle (heating) and the heat pump cycle (heating).

[Brief explanation of the drawing]

Figures 1 and 2 are explanatory diagrams for switching the number of poles during heating and cooling in a conventional multi-chamber heat pump type air conditioner, and Figure 3 is a multi-chamber heat pump type air conditioner that is an embodiment of the present invention. The schematic diagram of the configuration of the air conditioner, FIGS. 4 and 5, are explanatory diagrams of changes in the inverter frequency during heating and cooling of the air conditioner. 21... Bellows, 27... Permanent magnet, 28... Magnetoresistive conversion element. Figure 1 Figure 2 Figure 4 Figure 5

Claims (1)

[Claims] A bellows detects discharge pressure during heating and suction pipe pressure during cooling, and a permanent magnet is attached to this bellows, and when the bellows expands and contracts due to pressure, the permanent magnet also moves at the same time to calculate the resistance value. Equipped with a resistance conversion element,
The multi-chamber heat pump air conditioner continuously detects the discharge pressure during heating and the suction pressure during cooling, and controls the compressor by inverter frequency conversion using an electric signal converter.