JPS58123063A - Air conditioner for automobile - 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] This invention relates to an air conditioner for automobiles.

Especially when the heat load inside the vehicle is small, the air conditioning system for automobiles uses a slide valve to close the intake port of one cylinder of the compressor, thereby lowering the cooling capacity and reducing the compressor input. It is about improvement.

Conventionally, a refrigeration cycle of an automobile air conditioner is configured as shown in FIG. That is, in Figure 1,
(1) is a compressor, and (2) is a condenser.

(3) is the receiver dryer, (4) is the expansion valve, (5
) is an evaporator. In a closed-loop refrigeration cycle in which these are connected in series, the refrigerant is brought to high temperature and still pressure in the compressor (1), then sent to the condenser (2) to room temperature and high pressure, and then expanded in the receiver dryer (3) after eliminating pulsating flow. Inflate with valve (4),
The temperature is set to low temperature and pressure, and heat is absorbed in the evaporator (5).

However, with this configuration, during continuous high-speed operation or after the temperature inside the vehicle suddenly drops, cooling overload occurs, and the thermistor (not shown) detects the origin of cold air from the evaporator and compresses it. The machine turns ON and OFF frequently. At the same time, the blowing temperature goes up and down, but the air volume of the blower inside the car is more constant than #1. The temperature inside the vehicle is also controlled by turning the compressor on and off.
The temperature rose and fell depending on the cycle, causing uneven temperature. Furthermore, frequent ON-0vv shortens the life of the compressor, and the large shock caused by fluctuations in the engine speed at that time is also unpleasant for the driver.

This invention was made to eliminate such drawbacks, and has a coaxial two-cylinder structure with an intake valve and its two cylinders.
A slide valve that moves by pressure is provided between the suction ports of two cylinders, and the position of the slide valve changes the
A refrigeration cycle is constructed using a rolling piston type variable capacity compressor that can control the opening and closing of the inlets of two cylinders. When the heat load inside the vehicle is large, the slide valve is placed in a position where the intake ports of the two cylinders are open, allowing refrigerant to flow into both cylinders and exerting its original cooling capacity.

During continuous high-speed operation or when the heat load inside the vehicle is small, by blocking the intake port of one cylinder with a slide valve, the refrigerant will no longer flow into that cylinder and the cylinder will recycle. The object of the present invention is to provide an air conditioner for an automobile that can lower the cooling capacity and reduce the input to the compressor, thereby reducing the load on the compressor and allowing continuous operation.

The present invention will be explained below with reference to one illustrated embodiment.

Figure 2 shows the refrigeration cycle of the automobile air conditioner based on this invention. (1) has a coaxial, two-cylinder structure, and capacity can be controlled by controlling a built-in slide valve. A rolling piston type variable capacity compressor.

(2) is the condenser, (3) is the receiver dryer, (4
) is an expansion valve, (5) is an Fi evaporator, (6) is a pilot valve, (7) is a pilot tube, and (8) is a high pressure part of the refrigerant pipe. The compressor (l), condenser (2), receiver dryer (3), expansion valve (4), and evaporator (5) are connected in series, and the high pressure section (8) and the compressor (1) are connected in series. A pilot tube (7) is connected to the slide valve I that has been removed via a pilot valve (6). (9) is a controller.

The pilot valve (6) is controlled by receiving a temperature signal from a thermistor provided in a single chamber in front of the evaporator (5).

In the refrigeration cycle configured as described above, immediately after the start of cooling or when the heat load in a single room is high, such as when driving under the scorching sun, the pilot valve (6) is closed by the controller (9) K based on the temperature signal from the thermistor. Since high pressure is no longer applied to the slide valve ■, the suction ports of the two cylinders are operated in an open state, and the original cooling capacity of the two cylinders is exerted.

Next, when the heat load inside the vehicle is smaller than the rated cooling capacity of the compressor, such as during continuous high-speed operation, the temperature signal from the thermistor AL causes the controller (9) to open the pilot valve (6) and open the pilot tube (7). When high-pressure gas is passed through the slide valve aD built in the compressor 0), the spring (2) is compressed by the high pressure and moves in the direction of blocking the suction port of one cylinder, so that the cylinder is filled with refrigerant. The inflow is gone and it is running idle. As a result, cooling operation is performed using only one other cylinder, so the cooling capacity is reduced, and the input to the compressor +11 is also reduced, making it possible to reduce the load on the compressor and enable continuous operation. As a result, as shown in Figure 3, conventionally, as time passes and the temperature inside the vehicle becomes stable, a thermistor senses the temperature of cold air blown from the evaporator, and frequently turns ON -01PF.
However, according to the present invention, when the temperature inside the vehicle becomes stable, the pilot valve (6) is opened and the cooling capacity corresponding to the heat load in the vehicle interior is exerted, thereby keeping the temperature inside the vehicle constant. In addition, the load on the compressor is reduced and it operates continuously, eliminating the severe shock associated with fluctuations in engine speed when the compressor is ON - 0iFF. Furthermore, FIGS. 4 and 5 show the characteristics of the cooling capacity and compressor input depending on the engine speed, and show that opening the pilot valve (6) causes both the cooling capacity input to drop over the entire engine speed.

By the way, in the above example, a refrigeration cycle using a rolling piston type compressor was shown, but a multi-vane type compressor or a Wankel type compressor can also have a coaxial two-cylinder structure to create a similar refrigeration cycle and increase the cooling capacity. and control of compressor input is possible. Also, instead of the pilot valve, a solenoid valve or a nine-way switching valve using the negative pressure of the engine may be used. Also, the connection point between the pilot tube and the high pressure part of the refrigerant pipe is
Any location may be used as long as it is built into the compressor and has enough pressure to move the nine-slide valve.

As explained above, this invention uses a coaxial, two-cylinder rolling piston type variable capacity compressor with a built-in slide valve that moves based on the pressure difference between the high pressure gas sent from the pilot tube and the low pressure gas flowing from the suction valve. When a refrigeration cycle is formed, the slide valve moves according to the opening and closing of the pilot valve, closing the intake ports of the two cylinders, and controlling the flow of refrigerant by opening and closing the intake ports of the two cylinders. When it is small, it is possible to reduce the cooling capacity, operate the compressor continuously, and reduce the input.
The shock caused by JC movement is drastically reduced, and the temperature inside the vehicle is -
This has great effects, such as reducing driver discomfort.

[Brief explanation of the drawing]

Fig. 1 is a refrigerant circuit diagram in a conventional automobile air conditioner, Fig. 2 is a refrigerant circuit diagram showing an automobile air conditioner according to an embodiment of the present invention, and Fig. 3 is a time period for the vehicle interior temperature after cooling starts. Figure 4 is a characteristic curve diagram between engine speed and cooling capacity, Figure 5 is a characteristic curve diagram between engine speed and compressor input, and Figure 6 is a characteristic curve diagram showing changes due to rolling piston. FIG. 7 is a detailed view of the variable capacity compressor, with the pilot valve (6) closed, and FIG. 7 showing the same compressor with the pilot valve (6) open. (1) is a compressor, (2) is a condenser, (3) is a receiver dryer, (4) is an expansion valve, (5) is an evaporator, (61i
is the pilot valve, (force is the pilot tube, (8) is the connection point between the pilot tube and the high pressure part of the refrigerant pipe, (9)
) Jd controller, θ is the thermistor, 0υ is the slide valve, 02 is the spring, and al is the intermediate partition plate. (14a), (14t)) are cylinders, (15!
L), (15tl) is a rolling piston, aS
is a shell. Note that the same reference numerals in each figure indicate the same or corresponding parts. Agent Makoto Kuzuno - A few engineering steps > Circulation welcome @ 6 Figure 1 iq diagram

Claims (1)

[Claims] A coaxial two-cylinder structure with an intake valve. A variable-capacity compressor and condenser that has a slide valve that is moved by pressure between the two cylinders' suction ports, and the opening and closing of the two cylinders' suction ports can be controlled by the position of the slide valve. , receiver dryer, expansion valve. The evaporator is connected in series with piping to form a refrigeration cycle, and when the heat load in the cabin of a round car is large and the main engine of the car is the power source, the pilot valve is closed and the slide valve is moved to create a refrigeration cycle. The rated cooling capacity is achieved by fully opening the intake port of the second cylinder and allowing refrigerant to flow into the second cylinder. By blocking the intake port and eliminating the flow of refrigerant into the cylinder, the cylinder is emptied. An air conditioner for an automobile characterized by C lowering cooling capacity and lowering compressor input.