JPS58205059A - 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 The present invention relates to an air conditioner, and particularly to a heat pump type air conditioner having a liquid injection controller suitable for cooling the motor of a compressor having a high-pressure container.

The cycle of a conventional air conditioner is as shown in Figure 1.
, four-way valve 2, indoor heat exchanger 3, check valves 4a, 4b, and cabin') 5a + ``bs'' A circuit in which a pair of parallel circuits and an outdoor heat exchanger 6 are connected in series. The operation is shown by the solid line in the figure, and the heating operation is performed by circulating the refrigerant along the path shown by the broken line to form a cycle. The machine has a scroll type compression mechanism 11 and a motor 2 in a closed container 10.The scroll type compression mechanism 11 has an orbiting scroll 15 and a fixed scroll 1.
4. Frame 15 and crankshaft 16. The orbiting scroll 15 and fixed scroll 14 are made of plywood (mirror plate) 13
a, a scroll-shaped wrap 13 standing upright on 14a;
b, 14b, and are combined with each other with the wraps facing inward. An orbiting bearing 13C is installed on the back surface of the end plate 13a of the orbiting scroll 13. frame 1
5 and the fixed scroll 14Vi orbiting scroll are housed and fastened together. The frame 15 also supports a crankshaft 16, and the crank portion 16b of the crankshaft 16 is supported by a swing bearing i3.
inserted into c, ・1′.

The rotor 12a of the motor 2 is fixed to the other side.

The back surface of the end plate 13a of the orbiting scroll 15 and the 7 frames 15
A turning mechanism 13d is installed between the two. The back surface of the end plate 13a of the orbiting scroll 13 is separated from the inside of the closed container 10 by the frame 15. An oil supply hole 16a is provided in the crankshaft 16, and oil is supplied to each bearing portion from this oil supply hole 16a. The fixed scroll 14 is provided with a suction hole 14C and a discharge hole 14d, the suction hole 14C is provided with a suction pipe 17, and the closed container 10 is provided with a discharge pipe 18. 19 is an oil reservoir. 20 is a discharge gas passage, and 21 is an oil supply mechanism formed at the lower end of the crankshaft 16. When the motor 2 rotates, the orbiting scroll 13 and the fixed scroll 14 are rotated relative to each other by the crank of the crankshaft 16 and the rotation mechanism 13d, and the end plate 13a
, 14a and wrap 1. As the space formed in sb and 14b moves to the center, its volume decreases, compressing the gas inhaled from the suction hole 14C, and
Discharge from d. The discharged gas flows into space 2 inside the sealed container.
2. After the motor 2 is cooled through the discharge gas passage 20, it is discharged through the space 25 and into the discharge pipe 18. Since the motor 12 is cooled by the discharged gas, the load on the compressor increases, and if the temperature of the discharged gas rises, the cooling effect decreases, causing the motor to overheat and burn out. In order to prevent this burnout, it is necessary to lower the temperature of Ct discharged gas, and one possible method for this is to inject liquid refrigerant into the suction gas of the compressor or into the compression process.

In this method, for example, as shown in FIG. 3, part of the liquid refrigerant is supplied by injection from the liquid line 9 of the cycle to the compressor 1 via the solenoid valve 7.

The method described above requires a solenoid valve and a magnetic switch 8 for actuating the solenoid valve, which has disadvantages such as increased cost. In addition, in a method that does not use a solenoid valve, liquid refrigerant is constantly supplied to the compressor, so liquid refrigerant is supplied even when cooling is not required, resulting in an abnormal decrease in the company gas source, a decrease in heating capacity, and a decrease in the compressor. This causes problems such as liquid pooling inside, reduced cooling capacity, and increased compressor input. Furthermore, even in a structure using a solenoid valve, the resistance of the liquid injection piping is constant, so the amount of liquid injection is determined by the pressure difference between the high-pressure liquid refrigerant section and the injection section, so the compressor operation Acted by the pressure of the state,
It has the disadvantage that the amount does not necessarily correspond to the amount necessary for cooling the motor.

SUMMARY OF THE INVENTION An object of the present invention is to provide an air conditioner having means for controlling the amount of liquid injection necessary for cooling a compressor motor.

In order to achieve the above object, the present invention provides a liquid volume control valve with a built-in heat-responsive shaped memory element at a location in the yarn path where liquid refrigerant is injected into the compressor, where the heat generation of the compressor can be detected. The present invention is characterized by a configuration in which the resistance of the liquid injection piping is changed according to the amount of cooling required for the motor, and an appropriate amount of liquid refrigerant is supplied.

An embodiment of the present invention will be described in detail with reference to one embodiment shown in FIGS. 4 to 8.

In the figure, parts that are the same or similar to those in FIGS. 1 to 3 are denoted by the same reference numerals, and the explanation thereof will be omitted.

In FIG. 4, 24 is an injection pipe which connects the liquid line 9 of the cycle and the suction pipe 17 of the compressor 1. Reference numeral 25 denotes a liquid volume regulator using a shape memory element, which is provided in the middle of the injection pipe 24 and in contact with the compressor 1. The 771 liquid volume regulator 25Vi uses a shape memory element that expands and deforms depending on the temperature, and when the temperature of the compressor gets high, the dimensions expand, and when the temperature gets low, the dimensions shrink, increasing or decreasing the valve opening degree. have. The temperature of the motor is primarily governed by the temperature of the discharged gas.

On the other hand, since the temperature of the compressor is also proportional to the temperature of the discharged gas, the temperature of the motor can be controlled via the temperature of the compressor to perform appropriate cooling.

5 to 7 show examples in which this liquid volume regulator 25 is provided inside the compressor 1.

In this case, the liquid part of the cycle and the inside of the compressor are connected by an injection pipe 24. As shown in FIG. 6, the liquid volume regulator 25 is installed in contact with the end plate 14a of the fixed scroll, and opens into a compression chamber 26 formed by the end plate 14a1 of the fixed scroll, the lug 14b1, the end plate 13a1 of the orbiting scroll, and the wrap 13b. The liquid amount regulator 25□ adjusts the injection amount by changing its opening degree depending on the temperature of the end plate 14a of the fixed scroll.

Furthermore, as shown in FIG.
Another method is to install it in contact with the motor coil and change the opening degree directly depending on the motor temperature.

As shown in FIG. 8, an example of the liquid volume regulator 25 has a structure in which the opening degree is changed directly or indirectly by a shape memory element that expands upon receiving heat. 28
A valve 30 is inserted into the valve body 29 having a diameter corresponding to the valve seat 28, and a number of passages 31 are cut into the valve 30. 32 is a valve cover. Reference numeral 33 denotes a thermally responsive shape memory element, which is formed into a cylindrical shape and is inserted into an annular groove 34 formed in the valve body 29. The upper surface of the heat-responsive shape memory element 33 supports the lower surface of the flange portion 35 of the valve 30. 36 is a passageway opening.

Although the cross section of the heat-responsive shape memory element 33 is shown to be rectangular, by arbitrarily changing the cross-sectional shape, the amount of deformation due to heat can be varied and the characteristics can be changed.

Although this embodiment shows only the case where a scroll compressor is used, it is of course applicable to other types of high-pressure container compressors such as rotary compressors and even reciprocating compressors. .

r1 Since the present invention is configured as described above, parts such as a stain magnetic valve and a magnetic switch are used in the liquid volume regulator whose opening degree changes directly or indirectly in response to the temperature of the compressor or motor. Since it is possible to inject as much liquid refrigerant as necessary to cool the motor, motor burnout can be prevented without unnecessarily reducing the performance of the compressor and air conditioner.

[Brief explanation of drawings]

Figures 1 and 3 are block diagrams showing the cycle of a conventional air conditioner, Figure 2 is a structural sectional view of a conventional scroll compressor,
Figures 4 and 5 are block diagrams showing the cycles of the air conditioner of the present invention, Figures 6 and 7 are structural sectional views of the scroll compressor of the present invention, and Figure 8 is the liquid volume regulator of the present invention. FIG. 1... Compressor, 2... Four-way valve, 5... Indoor heat exchanger, 4a, 4b... Check valve, 5a, 5t)...
Capillary, 6... Outdoor heat exchanger, 7... Solenoid valve,
8...Magnetic switch, 9...Liquid line, 10
... Airtight container, 11 ... Scroll type compression mechanism, 1
2...Motor, 13...Orbiting scroll, 13a.
...End plate, 15b...Wrap, 13C...Swivel bearing, 13d...0c1 turning mechanism, 14...Fixed scroll, 14a...End plate, 14b...Wrap, 14C...Suction hole , 14d
... Company hole, 15... Frame, 16... Crankshaft, 16a... Oil supply hole, 17... Suction pipe, 18...
...Discharge pipe, 19...Oil reservoir section, 20...Discharge gas passage, 21...Oil supply mechanism, 22.25...Space, 24
...injection piping, 25...liquid volume regulator,
26... Compression chamber, 27... Passage opening, 28... Valve seat, 29... Valve body, 30... Valve, 31... Passage,
32... Valve lid, 33... Thermal response shape memory element, 3
4... Annular groove agent Patent attorney Tadashi Akimoto 4Q Figure 5 Figure 6 Diagram l District 7 1 Continuation of page 1 Figure 8; ti 272B34 Muramatsu 3, Shimizu City
90 Hitachi, Ltd. Mechanical Research Laboratory

Claims (1)

[Claims] 1. A cycle is formed in which a compressor, a condenser, an expansion valve, and an evaporator are connected in series, and a portion of liquid refrigerant is injected into the compressor from the liquid line. The air conditioner is characterized in that a liquid volume control valve having a built-in heat-responsive shape memory element is provided at a location in the path where liquid refrigerant is injected into the compressor at a location where heat generation from the compressor can be detected. Air conditioner. 2. The air conditioner according to claim 1, wherein a liquid volume control valve incorporating a heat-responsive shape memory element is provided in contact with the surface of the compressor. 3. The air conditioner according to claim 1, wherein a liquid volume control valve incorporating a heat-responsive shape memory element is provided at a location within the compressor where discharged gas can be detected. 4. The air conditioner according to claim 3, wherein the location where discharged gas can be detected is an end plate of a fixed scroll of a scroll compressor. 2. 5. The air conditioner according to claim 1, wherein a liquid i control valve incorporating a heat-responsive shape memory resistor is attached to a coil portion of a motor inside a compressor. 6. A liquid volume control valve with a built-in heat-responsive shape memory element includes a valve body having a valve seat opening into a passage opening, a valve cover opening the passage opening inside the valve, and a passage corresponding to the valve seat. and a heat-responsive shape memory element disposed between the valve body and the valve and expanded by heating to move the valve and change the opening degree of the passage. Air conditioner.