JPS6275084A - Automatic flow control valve for compressor - Google Patents

Abstract

PURPOSE:To sufficiently cool an electric motor part and to prevent seizure in a bearing part, by mounting a shape memory alloy-made automatic flow control valve, connected with a bypass pipe communicating with the delivery side of a condenser, to a subbearing while providing said valve to be brought into contact with lubricating oil stored in a compressor case. CONSTITUTION:An automatic flow control valve 36, using a shaped memory alloy, is connected with a bypass pipe 35 communicating with the delivery side of a condenser, and the valve 36, being mounted to a subbearing 9, is provided so as to come into contact with stored lubricating oil 4 in the bottom part of a vessel 1. Said valve 36, if the temperature of a driving spring increases to a fixed value or more, injects a liquid refrigerant, condensed in the condenser, from the bypass pipe 35 to a compression chamber 6, and a compressor is cooled by cooling refrigerant gas. And the injection is ceased of the temperature of the driving spring decreases to the fixed value or less. And the temperature of the driving spring is controlled almost by the temperature of the lubricating oil 4 of large heat capacity. In this way, the automatic flow control valve 36 is controlled by the temperature of the lubricating oil 4 serving as the reference, and the compressor, being cooled,enables an electric motor part to be sufficiently cooled while seizure in a bearing part to be prevented.

Description

[Detailed description of the invention]

TECHNICAL FIELD OF THE INVENTION The present invention relates to a compressor that uses an automatic flow control valve to inject liquid refrigerant into a compression chamber. [Technical Background of the Invention and Thousand Problems] In the refrigeration cycle, in order to prevent various problems such as a decrease in efficiency due to overheating of the compressor, seizure of the bearing, and deterioration of the insulation material of the stator, The compressor was cooled by directly injecting condensed liquid refrigerant into the compression chamber of the compression mechanism. In a refrigeration cycle in which the liquid refrigerant condensed in the condenser is directly injected into the compression chamber of the compression mechanism using an automatic flow control valve using a shape memory alloy, the automatic flow control valve is shown in Figure 3. It was constructed as shown in Figure 1 and installed as shown in Figure 2. An inlet 102 and an outlet 103 for liquid refrigerant are provided on the side surface of a cylindrical case 101 forming a cylinder. This inlet is connected to the outlet side of a condenser (not shown) via a pipe 104, and the outlet is connected to a compression chamber 105 of the compression mechanism section. Inside this cylindrical case 101, there is a communication groove 10 which is cylindrical and extends in the circumferential direction on its circumferential surface.
A flow path M closing member 107 formed with a cylindrical case 101 is slidably attached to the cylindrical case 101 in the direction of its central axis. This channel opening/closing member 107 is supported at both ends of the cylindrical case 101 via two springs, namely a bias spring 108 and a drive spring 109 made of shape memory alloy. With such a configuration, when the temperature of the compressor is low, the drive spring 109 is in a contracted state and the flow path opening/closing member 107 is closed.
The inflow port 102 and the outflow port 103 are placed at appropriate locations on the outer peripheral surface of the
When the temperature of the compressor exceeds a predetermined temperature, the drive spring 109
expands, and the inlet 102 and outlet 103 communicate with the communication groove 106 of the channel opening/closing member 107.

[7] The liquid refrigerant condensed in the condenser was directly injected into the compression chamber of the compression mechanism to cool the compressed air. Considering the operation of the automatic flow rate control valve in detail, after the start of operation, the cylindrical case 101 is heated, the drive spring 107 is heated and expanded, and when the set temperature is reached, the liquid refrigerant flows into the compression chamber. At this time, the liquid refrigerant cools the refrigerant gas and at the same time forms a compression chamber and also cools the cylinder in which the automatic flow control valve is installed. Therefore, the cylinder is cooled before the entire compressor is sufficiently cooled, and the cylindrical case 101
When the refrigerant is cooled, the drive spring 107 contracts and the liquid refrigerant stops flowing into the compression chamber. Furthermore, there is no correlation between the temperature of the electric motor section that requires the most cooling and the temperature of the cylinder 110 to which the automatic flow rate control valve is attached, and the temperature of the electric motor section is particularly low when controlling the rotation speed using an inverter or the like. Due to the large fluctuations,
There was a problem in that the motor section could not be cooled when it was really necessary. [Object of the Invention] An object of the present invention is to provide sufficient cooling of a compressor by accurately controlling an automatic flow control valve. [Summary of the Invention] The present invention is characterized in that an automatic flow control valve provided between the outflow side of the condenser and the compression chamber of the compression mechanism is attached to a sub-bearing. [Embodiment of the Invention] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a vertical sectional view of a compressor showing an embodiment of the present invention. 1 has an opening at the top [. A closed space 3 is formed by closing the upper opening of the container 1 with an upper container 2. The container 1 and the upper container 2 are integrally fixed by welding or the like. Lubricating oil 4 is stored in the lower part of the container 1. Next, let's talk about the compression mechanism trap. A cylinder 5 half immersed in lubricating oil 4 is press-fitted into the lower part of the container 1. A circular through lower portion forming a compression chamber 6 and a through groove 8 are provided in the center of the cylinder 5 . An auxiliary bearing 9 that covers the lower through-hole is fixed to the lower surface of the cylinder 5 by bolts (not shown). A countershaft portion 12 of a main shaft 10 is fixedly inserted into the counterbearing 9. A roller 13 is provided on the outer periphery of the crank portion 11 of the main shaft 10.
is inserted. A blade 14 having the same height as the roller 13 is slidably housed in the through groove 8 , one end of which contacts the peripheral wall of the roller 13 , and a spring 15 in the space within the through groove 8 between the other end and the container 1 . is accommodated and is in contact with the peripheral wall of the roller 13 by the elastic force of the spring 15. A main shaft 10 is inserted into the upper surface of the cylinder 5, and a main bearing 16, which is provided so as to cover the through lower part, is fixed by a bolt (not shown). A spiral groove for oil supply is cut in the surface of the main bearing 16 that contacts the main shaft 10. The main bearing 16 has a discharge port 1
7 is provided, and a discharge valve 18 is provided to cover this port. A discharge muffler 19 is provided over the discharge port 17 and the discharge valve 18 and is fixed to the main bearing 16 so as to cover them and forms a space for storing discharged gas. This discharge muffler 19 has a discharge valve 1 centered around the main shaft 10.
An opening side is provided on the wall surface opposite to where 8 is provided, and gas is discharged 7 into the closed space 3 through this opening side. The main shaft] 0 is hollow inside, and a vane pump n for scooping up lubricating oil 4 is installed below. Main shaft 1
A rotor which forms a part of the motorized part is press-fitted into the rotor 0 and is integrally formed with the main shaft lO, and a status press-fitted into the container 1 is provided on the outside of the rotor. Stator Ani Stator Coil! is wrapped. Further, above this, an oil disk 25 having an oil separation function using a centrifugal chamber is fixed to the main shaft 10. Upper cover 2
A discharge vibrator 32 is fixed to the holder. In the rotary compressor having such a structure, according to the present invention, the bypass pipe connected to the discharge side of the condenser is attached to the sub-bearing 9 between the flow 1 control valves and the bypass pipe connected to the discharge side of the condenser. Next, the operation based on the above configuration will be explained. When a commercial voltage or commercial frequency power is applied to the electric part from a power terminal (not shown) of the rotary compressor, the rotor begins to rotate, and the integrated main shaft also rotates. Main shaft 1
0 rotation causes the roller 13 to perform eccentric rotation within the cylinder 5. Due to this eccentric rotation, the volume of the compression chamber 6 formed by the lower passage and the roller 13 is varied and a compression action is performed. Due to this compression action, the refrigerant gas sucked in from the suction port (not shown) is compressed in the compression chamber 6, is discharged from the discharge port 17 and the discharge valve 18 into the space of the muffler 19, and exits from the closed space 3 through the opening of the muffler 19. . Then, the refrigerant gas passes upward through the gap formed by the stator part 11 and the stator part, and the stator part and the container 1, and passes through the discharge pipe 3.
It is discharged from 2. The refrigerant gas is blown around the disk 25 by the centrifugal force of the oil disk O. At that time, the lubricating oil 4 collides with the stator coil of the stator or the inner wall of the closed container 1 and is captured, separating the lubricating oil from the refrigerant gas. Then, from the upper surface of the stator, pipes are connected to container 1.
Return to Shoyu 4 at the bottom. The automatic flow control valve injects the liquid refrigerant condensed in the condenser into the compression chamber 6 through the vibrator when the temperature of the drive spring exceeds a certain temperature. Thereby, the refrigerant gas is cooled and the compressor is cooled. When the temperature of the drive spring drops below a certain temperature, injection is stopped. The temperature of the drive spring is approximately controlled by the temperature of the large lubricating oil in the thermal vessel. The temperature of the lubricating oil is the highest and returns to the lower part of the compression chamber after passing through the motor section which requires cooling, so it changes in proportion to the temperature change in the motor section I7. Therefore, based on the temperature of the lubricating oil, it is possible to protect the windings of the motor, prevent efficiency from decreasing due to overheating, and prevent seizure of the bearing. [Effects of the Invention] As described above, by providing the automatic flow control valve in contact with lubricating oil, the electric motor section can be sufficiently cooled, the windings of the electric motor section can be protected, efficiency can be prevented from decreasing due to overheating, and the bearing section can be cooled sufficiently. It is possible to prevent burn-in.

[Brief explanation of drawings]

Fig. 1 is a sectional view of a compressor showing one embodiment of the present invention;
The figure is a sectional view of the compression mechanism section of a conventional compressor, and FIG. 3 is an example of an automatic flow control valve used in the present invention and the conventional example. 4...Lubricating oil, 35...Bypass pipe, Ah...Automatic flow control valve. Agent Patent attorney Kensuke Chika (and 1 other person) ¥? 1 6 Indentation 1 (-tt+M plane drawing top'4 3 Sectional drawing Iin

Claims (1)

[Claims] In a refrigeration cycle in which liquid refrigerant condensed in a condenser is directly injected into a compression chamber of a compression mechanism section through a bypass pipe using an automatic flow control valve using a shape memory alloy, the automatic flow control valve is connected to a compressor case. An automatic flow control valve for a compressor, characterized in that it is provided so as to be in contact with lubricating oil stored therein.