KR20000015668A - Pressure balancing device of compressor - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pressure equalizer of a compressor. In the related art, the suction / discharge pressure is equilibrated to a certain degree during a time when the compressor is stopped while the refrigeration cycle is stopped (compressor stop). As a result, when the compressor restarts operation, the compressor is sucked at an equilibrium pressure that differs from the actual normal suction pressure during the initial few seconds, which overloads the starting of the induction motor. In the present invention, the pressure sensing means for detecting the pressure of the refrigerant in the low-temperature low-pressure state flowing out from the evaporator constituting the refrigeration cycle apparatus flows into the compressor, and the pressure sensing means Of the refrigerant flowing into the cylinder by opening and closing the suction pipe according to the detected pressure of the refrigerant. By providing a pressure balance device of the compressor comprising a refrigerant amount adjusting means for adjusting the amount and a control means for driving and controlling the refrigerant amount adjusting means by the detection of the pressure sensing means, the suction inside the compressor at high pressure The system forms a nozzle-type flow path resistance, which prevents the suction of refrigerant into the suction pipe at the beginning of the compressor to prevent noise and pressure escalation, and when the pressure decreases, it is reduced to the normal suction system flow path to maintain the original function and performance of the compressor. do.

Description

Pressure equalizer of the compressor

The present invention relates to a pressure equalizer of the compressor, in particular, to prevent the pressure rise in the initial starting state of the compressor by preventing the high-pressure refrigerant is sucked into the compressor when the compressor is initially started in the refrigeration cycle is stopped. A pressure equalizer of a compressor for reducing.

Generally, a refrigeration cycle is applied to a refrigerator or an air conditioner to absorb heat from the outside or release heat to the outside to keep food fresh and to cool / heat the room to keep the indoor environment comfortable.

As shown in FIG. 1, the refrigeration cycle apparatus includes a compressor (1) for converting a gaseous refrigerant of low temperature and low pressure into a gaseous state refrigerant of high temperature and high pressure, and a gaseous state of high temperature and high pressure changed in the compressor (1). A condenser (2) for dissipating heat to the outside while changing the refrigerant into a liquid at a high temperature and high pressure, and an expansion mechanism (3) for changing the liquid refrigerant of the high temperature and high pressure changed in the condenser (2) into a liquid refrigerant of low temperature and low pressure. And an evaporator 4 for absorbing external heat while changing the liquid refrigerant having a low temperature and low pressure changed in the expansion mechanism 3 into a gas state, wherein each of the components is connected to the refrigerant pipe 5. It is.

The sealed reciprocating compressor applied to the refrigeration cycle as described above, as shown in Figure 2, the upper container (11a) and the lower container (11b) is coupled to the closed container 11 having a predetermined internal volume, and It is installed on the inner lower portion of the sealed container 11 to generate a driving force by the power supplied from the outside, and is installed on the inner upper portion of the sealed container 11 to receive the driving force of the electric mechanism portion to suck the gas Compression mechanism portion for compressing, the sealed container 11 is provided with a support spring 12 for supporting the power mechanism and the compression mechanism portion.

The motor mechanism part includes a stator 14 fastened to and supported by the frame 13 and a rotor rotatably coupled to the stator 14 to form an induction motor together with the stator 14. 15 and a rotating shaft 16 press-fitted to the rotor 15 so as to penetrate the center of the frame 13 to transmit the power of the electric mechanism part to the compression mechanism part.

The rotating shaft 16 has a rotating portion 16a formed at the lower portion thereof coupled with the rotor 15, while an upper portion of the rotating shaft 16 has an eccentric portion 16b for converting the rotational movement of the electric mechanism into a linear movement of the compression mechanism. .

As shown in FIG. 3, the compression mechanism has a predetermined internal volume and is inserted into the cylinder 17 and the cylinder 17 fastened to the frame 13 by a fastening member such as a bolt (not shown). A piston 18 for compressing / discharging refrigerant gas while being linearly moved by the rotary shaft 16, and is slidably inserted into the piston 18 and slidably coupled to an eccentric portion 16a of the rotary shaft 16. A slider 19 for converting the rotational movement of the rotary shaft 16 into a linear reciprocating motion of the piston 18, a valve assembly mounted at the other end of the cylinder 17 to regulate suction / discharge of refrigerant gas, and the valve It consists of a head cover 20 for covering the assembly, the suction pipe 21 and the discharge pipe 22 is installed on the suction side and the discharge side of the valve assembly, respectively, the respective suction pipe 21 and discharge pipe ( 22) to reduce suction noise and discharge noise. The suction muffler 23 and the discharge muffler 24 for tightening are installed.

That is, the valve assembly includes a suction valve 26 and a discharge valve 27 fastened to each other by the bolt 25 with the head 25 interposed therebetween. A discharge valve 25a and a discharge port 25b are formed, and a suction valve 26 for opening and closing the suction port 25a is provided between the head 25 and the cylinder 17 and the discharge valve for opening and closing the discharge port 25b. 27 is installed between the head 25 and the head cover 20.

A packing cover 28 is installed between the discharge valve 27 and the head cover 20 to prevent leakage of the refrigerant.

Meanwhile, the head cover 20 has a structure in which the first head cover 20a and the second head cover 20b divide a predetermined space, and the head cover 20 is divided into two spaces. The space located on the formed suction port 25a side is called the suction space F1, and the space located on the discharge port 25b side formed on the head 25 is called the discharge space F2.

Referring to the operation of the hermetic reciprocating compressor having the above structure as follows.

When power is applied to the induction motor consisting of the stator 14 and the rotor 15, an induction current is generated between the stator 14 and the rotor 15 to rotate the rotor 15, As the electron 15 rotates, the rotating shaft 16 press-fitted into the rotor 15 rotates. In response to the rotation of the rotary shaft 16, the piston 18, which interlocks with the movement of the slider 19 coupled to the outer circumference of the eccentric portion 16b provided on the rotary shaft 16, inserts the slider 19 into the cylinder 17. Reciprocating in the compression chamber (R) formed in the).

As described above, when the piston 18 moves backward in the cylinder 17 (this is called a suction stroke), the refrigerant gas having a low temperature and low pressure is sealed through a suction tube (not shown) installed in the sealed container 11 ( 11) The low-temperature low-pressure refrigerant gas sucked into the sealed container 11 is sucked into the suction muffler 23 through the suction pipe 21, and then suction is formed in the first head cover 20a. After being sucked into the platen F1, it is guided to the suction port 25a formed in the head 25 to open the suction valve 26 and sucked into the compression chamber R.

The low-temperature low-pressure refrigerant gas sucked into the compression chamber R as described above is the intake valve 26 when the piston 18 finishes the backward movement and starts the forward movement (in this case, compression stroke) in the cylinder 17. ) Is compressed into a refrigerant gas of high temperature and high pressure in the compression chamber (R).

When the refrigerant gas compressed at a high temperature and high pressure in the compression chamber R reaches a predetermined pressure (compression stroke completion), the discharge valve 27 is opened to discharge through the discharge port 25b formed in the head 25. It is discharged to the platen F2.

The high temperature, high pressure refrigerant gas discharged to the discharge platen F2 is discharged into the discharge muffler 24 provided at one end of the first head cover 20a, and then the discharge pipe installed at the discharge muffler 24 ( 22 is sent to the condenser 2 of the refrigerant cycle shown in FIG. 1 through a discharge tube (not shown) installed in the sealed container 11.

As such, the refrigerant gas sent to the gaseous state of high temperature and high pressure is condensed into the liquid refrigerant of room temperature and high pressure in the condenser 2, and the liquid refrigerant of room temperature and high pressure passing through the condenser 2 passes through the expansion valve 3. It is adiabatic expansion and is converted into a low temperature low pressure liquid refrigerant, and the low temperature low pressure liquid refrigerant changed in the expansion valve (3) is changed into a gas state by the evaporator (4) to maintain the temperature by absorbing external heat. Done.

As shown in FIG. 1, the compressor 1 includes a condenser 2, an expansion valve 3, and an evaporator 4 to form a refrigeration cycle, and immediately before the compressor 1 is operated. The refrigerant is distributed at an equilibrium pressure of about several kilograms per square centimeter / cm 2, and this equilibrium pressure corresponds to a very high pressure compared to the suction pressure of the compressor (1) during actual refrigeration cycle operation.

Therefore, the related art has a high pressure when the compressor 1 is restarted in a state where the suction / discharge pressure of the compressor 1 is balanced to some extent during the time when the compressor 1 is stopped in the stopped state of the refrigeration cycle (compressor stop). When the compressor 1 restarts operation by sucking the refrigerant, the suction of the compressor 1 takes place at an equilibrium pressure that is different from the actual normal suction pressure for the first few seconds, thereby overloading the starting of the induction motor. There was a problem that caused the malfunction of the induction motor or a serious level of noise and pressure rise.

Accordingly, the present invention has been made in order to solve the above-mentioned conventional problems, by preventing the intake of high-pressure refrigerant inside the compressor when the compressor is initially started in the refrigeration cycle stop state by the inside of the compressor in the initial starting state of the compressor It is an object of the present invention to provide a pressure equalizer of a compressor for reducing the increase in pressure.

1 is a schematic view showing a typical refrigeration cycle device.

Figure 2 is a longitudinal sectional view showing a typical hermetic reciprocating compressor.

Figure 3 is a longitudinal sectional view showing a compression mechanism of the conventional compressor.

4 and 5 show a pressure equalizer of the compressor according to the present invention,

4 is a schematic view showing a pressure equalizer when the compressor is stopped.

5 is a schematic view showing a pressure equalizer during operation of the compressor.

** Explanation of symbols for main parts of drawings **

110; Refrigerant amount adjusting means 111; Fixture

112; Opening and closing portion 112a; Refrigerant suction hole

113; Ring 120; Pressure sensing means

131; Heater 132; Bimetal switch

133; Electromagnet

Therefore, the present invention is a pressure sensing means for detecting the pressure of the refrigerant in the low-temperature low-pressure state flowing out from the evaporator constituting the refrigeration cycle apparatus in order to achieve the object of the present invention as described above, and the pressure sensing means Refrigerant amount adjusting means for controlling the amount of refrigerant flowing into the cylinder by opening and closing the suction pipe in accordance with the pressure of the refrigerant detected by the refrigerant, and control means for driving and controlling the refrigerant amount adjusting means by the detection of the pressure sensing means. It provides a pressure equalizer of the compressor, characterized in that.

Hereinafter, an embodiment of a pressure balancing device of a compressor according to the present invention will be described with reference to the accompanying drawings.

The pressure balancing device of the compressor according to the present invention, as shown in Figure 4, by opening and closing the inlet of the suction pipe 21, the refrigerant amount adjusting means 110 for adjusting the amount of refrigerant flowing into the suction pipe 21, Pressure sensing means 120 for detecting the pressure of the low-temperature low-pressure refrigerant flowing out of the evaporator which is one of the components constituting the refrigeration cycle device flows into the sealed container of the compressor through a suction pipe (not shown), and the pressure sensing means It consists of a control means for driving the refrigerant amount adjusting means 110 by the detection of (120).

The refrigerant amount adjusting means 110 is connected to the fixing portion 111 is inserted and coupled to the outer diameter of the end of the suction pipe 21 and the connecting ring 113 having a predetermined elastic force on the upper side of the fixing portion 111 and the suction The opening and closing portion 112 is formed with a refrigerant suction hole 112a smaller than the inner diameter of the pipe 21.

That is, the fixing portion 111 of the refrigerant amount adjusting means 110 is inserted into the outer diameter of the end of the suction pipe 21 to maintain the inner diameter of the suction pipe 21, and the opening and closing portion 112 has a small hole in the center. As a form, the opening and closing portion 112 and the fixing portion 111 is connected to each other by a connection ring 113 having a predetermined elastic force so that the external medium does not act to the extent that does not interfere with the refrigerant flowing into the suction pipe 21 The opening and closing portion 112 is maintained at an angle of about 45 ° with respect to the fixing portion 111.

The pressure sensing means 120 is composed of a piezoelectric element for sensing the pressure of the refrigerant gas sucked into the sealed container through the suction pipe.

The control means includes a heater 131 connected to the piezoelectric element 120 to generate heat by receiving a current from the piezoelectric element 120, a bimetal switch 132 expanded and contracted by the heat of the heater 131, and It consists of an electromagnet 133 which generates a magnetic force by the operation of this bimetal switch 132.

The electromagnet 133 is wound around the conductor 133a attached to the end of the fixing portion 110 of the refrigerant amount adjusting means 110 is wound coil 133b is to act as an electromagnet when passing the power.

Reference numerals 132a and 132b denote the fixed contact point and the movable contact point, respectively.

Referring to the operation of the pressure equalizer of the compressor according to the present invention configured as described above are as follows.

During normal operation of the compressor, since the open circuit is shown in FIG.

Then, when the compressor is stopped with the refrigeration cycle stopped, the refrigeration cycle tries to maintain the equilibrium pressure state through diffusion by the pressure difference, and the suction side and the discharge side gradually achieve pressure equilibrium.

As a result, when the pressure inside the compressor increases, the piezoelectric element 120 installed inside the sealed container senses the pressure to generate charge.

The electric current generated by this charge activates the heater 131 connected through the conductive wires, and the generated heat is operated by operating the bimetal switch 132, that is, the two contacts in the separated state, that is, the movable contact 132b and the fixed contact. 132a are brought into contact with each other.

In this way, the main circuit connected by the bimetal switch 132 is connected to the compressor power and current flows, and the conductor 133a connected to one lower end of the fixing part 113 operates as the electromagnet 133 by the coil 133b. do.

At this time, the rotational speed of the coil 133b wound on the conductor 133a overcomes the spring repulsion force of the connecting ring 113 connecting the opening and closing portion 112 and the fixing portion 111 to fix the opening and closing portion 112 to the fixed portion ( 111) It should be sufficient to generate magnetic force that can be attached to it.

As described above, after a predetermined time after the compressor stops, the compressor suction pipe 21 is blocked except for the refrigerant suction hole 112a formed in the opening and closing portion 112 by the refrigerant amount adjusting means 110.

Thereafter, when the compressor is restarted, the refrigerant is sucked through the refrigerant suction hole 112a of the opening and closing portion 112, and the suction pressure is a pressure drop due to the flow path blocking effect and the throttling action of the refrigerant suction hole 112a. The pressure is almost the same as the suction pressure during normal operation, which can reduce the initial pressure rise, which is a problem of the existing compressor.

On the other hand, after a few seconds after the operation of the compressor, the piezoelectric element 120 no longer generates electric charge due to a drop in pressure in the sealed container, so that the heat generation of the heater 131 is stopped, which causes the bimetal switch 132 to be in a state before operation. It is reduced to cut off the switch of main circuit.

In this way, when the main circuit is opened again and the magnetic force of the electromagnet 133 is lost, the opening and closing portion 112 covering the suction pipe 21 is opened in the initial state of 45 ° by the elastic force of the connecting ring 113 and the suction flow path. It will not interfere with the compressor and will maintain normal compressor performance.

As described above, the pressure balancing device of the compressor according to the present invention prevents the suction of refrigerant from the suction pipe at the initial stage of the compressor by preventing the suction system inside the compressor from forming a nozzle-type flow path resistance at high pressure. By preventing the pressure surge and reducing the pressure to the normal suction flow path to maintain the original function and performance of the compressor, it is possible to reduce the starting load of the induction motor, thereby increasing the efficiency of the induction motor, thereby improving the performance of the compressor Will improve.

Claims (4)

Pressure sensing means for detecting the pressure of the refrigerant in the low temperature low pressure state flowing out from the evaporator constituting the refrigeration cycle device and the inside of the cylinder by opening and closing the suction pipe in accordance with the pressure of the refrigerant detected by the pressure sensing means Compressor amount adjusting means for adjusting the amount of refrigerant flowing into the pressure balancing device of the compressor, characterized in that it comprises a control means for driving and controlling the refrigerant amount adjusting means by the detection of the pressure sensing means. The pressure balancing device of claim 1, wherein the pressure sensing means is a piezoelectric element for sensing a pressure of refrigerant gas sucked into the compressor. According to claim 1, wherein the refrigerant amount adjusting means has a fixed portion inserted into the outer diameter of the suction pipe end, and a refrigerant suction hole smaller than the inner diameter of the suction pipe is formed and the amount of the refrigerant flowing into the suction pipe by opening and closing the suction pipe. Pressure adjusting device of the compressor, characterized in that the opening and closing portion for adjusting and the connecting ring for connecting the opening and closing portion and the fixed portion so as to have a certain elastic force relative to the fixed portion. 2. The heater of claim 1, wherein the control means is connected to the piezoelectric element to generate heat by receiving a current from the piezoelectric element, a bimetal switch operated by the heat of the heater, and generates a magnetic force by the operation of the bimetal switch. The pressure balancing device of the compressor, characterized in that consisting of an electromagnet for opening and closing the inlet of the suction pipe by the refrigerant amount adjusting means.