1. Field of the Invention
The present invention relates to a compressor, and, more particularly, to a smart control valve for compressors that is capable of easily accomplishing compression and communication in a compression chamber of a cylinder, without performing the repetitive on/off operation of the compressor, to change the capacity of the compressor.
2. Description of the Related Art
Generally, a refrigerating apparatus or an air conditioning apparatus, such as a refrigerator or an air conditioner, changes the state of refrigerant according to the principle of a refrigerating cycle to consecutively perform compressing, condensing, expanding and evaporating processes to maintain the interior of the refrigerating apparatus in a refrigerated state or the interior of a room where the air conditioning apparatus is installed in an air-conditioned state. To this end, the refrigerating apparatus or the air conditioning apparatus includes a compressor, a condenser, an expansion mechanism, and an evaporator.
The compressor serves to compress low-temperature and low-pressure refrigerant gas introduced into the compressor from the evaporator to change the low-temperature and low-pressure refrigerant gas into high-temperature and high-pressure refrigerant gas. Based on the structure, compressors are classified into an open-type compressor and a sealed-type compressor. The sealed-type compressor, including a drive unit and a compression unit mounted in a hermetically sealed container, is usually used in the refrigerator or the air conditioner. Based on the compression method, sealed-type compressors are classified into a reciprocating compressor, a centrifugal compressor, a rotary compressor, and a scroll compressor.
Meanwhile, an energy-saving operation of a refrigerating apparatus or an air conditioning apparatus, such as a refrigerator or an air conditioner, is generally performed as follows. When the temperature in the refrigerator or the temperature in a room where the air conditioner is installed reaches a predetermined temperature, the operation of the compressor of the refrigerator or the air conditioner is stopped. When the temperature in the refrigerator or the temperature in the room exceeds the predetermined temperature, on the other hand, the operation of the compressor of the refrigerator or the air conditioner is initiated. In this way, the operation of the compressor is repetitively turned on and off. Generally, power consumption when the operation of the compressor is initiated is greater than power consumption when the compressor is normally operated. Furthermore, interference between the compressed gas in the compressor and the parts of the compressor is caused due to abrupt interruption of the compressor and initiation of the compressor, and therefore, the parts of the compressor are prematurely worn, which reduces the service life of the compressor.
For this reason, it is required to change the capacity of the compressor without performing repetitive on/off operation of the compressor as described above. An inverter system may be used to change the capacity of the compressor. In the inverter system, the number of rotations of the motor is controlled to change the capacity of the compressor. However, the inverter system has problems in that expensive electric circuit control devices and relevant parts are needed. Consequently, the manufacturing costs of the compressor are increased, and therefore, the competitiveness of the product is decreased.
Therefore, the present invention has been made in view of the above problems, and it is an object of the present invention to provide a smart control valve for compressors that is capable of easily accomplishing compression and communication in a compression chamber of a cylinder, without performing the repetitive on/off operation of the compressor, to change the capacity of the compressor, thereby reducing power consumption due to repetitive on/off operation of the compressor, preventing reduction in service life of the compressor due to premature wear of the parts of the compressor, and accomplishing economical efficiency of the compressor.
In accordance with the present invention, the above and other objects can be accomplished by the provision of a smart control valve for compressors, comprising: a valve body mounted on a cylinder including a refrigerant inlet port and a refrigerant outlet port; a valve inlet port formed at the valve body, the valve inlet port communicating with the refrigerant inlet port of the cylinder; a valve outlet port formed at the valve body, the valve outlet port communicating with the refrigerant outlet port of the cylinder; an actuating groove disposed under the valve inlet port and the valve outlet port of the valve body, the actuating groove being opened at one side thereof; and an actuator disposed in the actuating groove for performing a linear reciprocating movement in the actuating groove as a solenoid is operated.
Preferably, the cylinder further includes an annular space defined between an inner ring and an inner wall thereof, and the smart control valve further comprises: an orbiting vane, having a circular vane, disposed in the annular space.
Preferably, the annular space of the cylinder is divided into inner and outer compression chambers by the circular vane of the orbiting vane.
Preferably, the cylinder further includes: inner refrigerant inlet and outlet ports communicating the inner compression chamber; and outer refrigerant inlet and outlet ports communicating the outer compression chamber, the inner refrigerant inlet and outlet ports being opposite to the outer refrigerant inlet and outlet ports about the valve body.
Preferably, the actuator includes: a discharge side opening/closing hole formed at the other longitudinal side thereof for allowing or interrupting communication between the valve outlet port and the refrigerant outlet port of the cylinder; and a communication groove formed at the other longitudinal side thereof, the communication groove having an open side.
Preferably, the actuator includes: a discharge side opening/closing hole formed at the other longitudinal side thereof for allowing or interrupting communication between the valve outlet port and the refrigerant outlet port of the cylinder; an elongated suction hole formed at the other longitudinal side thereof for maintaining communication between the valve inlet port and the refrigerant inlet port of the cylinder; and a communication groove disposed under the elongated suction hole, the communication groove extending toward the discharge side opening/closing hole and opposite ends of the communication groove being closed.
Preferably, the actuator includes: a communication groove formed at the lower part thereof, opposite ends of the communication groove being closed; a suction side opening/closing hole disposed above the communication groove adjacent to one side of the lower communication groove, the suction side opening/closing hole communicating with the communication groove; a communication hole disposed above the communication groove adjacent to the other side of the lower communication groove, the communication hole communicating with the communication groove; and a discharge side opening/closing hole disposed adjacent to the communication hole for allowing or interrupting communication between the valve outlet port and the refrigerant outlet port of the cylinder.
Preferably, the actuator includes: a discharge side opening/closing hole formed at one longitudinal side thereof for allowing or interrupting communication between the valve outlet port and the refrigerant outlet port of the cylinder; an elongated suction hole formed at the other longitudinal side thereof for maintaining communication between the valve inlet port and the refrigerant inlet port of the cylinder; a communication groove formed at the lower part thereof between the elongated suction hole and the discharge side opening/closing hole, opposite ends of the communication groove being closed; and a suction guide disposed between the elongated suction hole and the communication groove. Also, the cylinder includes an upper open groove disposed between the refrigerant inlet port thereof and the refrigerant outlet port thereof, the upper open groove being opposite to the communication groove of the actuator.
Preferably, the actuator includes: a discharge side opening/closing hole formed at one longitudinal side thereof for allowing or interrupting communication between the valve outlet port and the refrigerant outlet port of the cylinder; a suction side opening/closing hole formed at the other longitudinal side thereof for allowing or interrupting communication between the valve inlet port and the refrigerant inlet port of the cylinder; a communication hole disposed between the suction side opening/closing hole and the discharge side opening/closing hole; a first communication groove disposed under the suction side opening/closing hole, the first communication groove communicating with the suction side opening/closing hole and opposite ends of the first communication groove being closed; a second communication groove disposed under the communication hole, the second communication groove communicating with the communication hole and opposite ends of the second communication groove being closed; and a suction guide disposed between the first communication groove and the second communication groove. Also, the cylinder includes an upper open groove disposed between the refrigerant inlet port thereof and the refrigerant outlet port thereof, the upper open groove being opposite to the second communication groove of the actuator.
Preferably, the actuator includes: first and second discharge side opening/closing holes formed at one longitudinal side thereof for allowing or interrupting communication between the valve outlet port and the refrigerant outlet port of the cylinder; an elongated suction hole formed at the other longitudinal side thereof for maintaining communication between the valve inlet port and the refrigerant inlet port of the cylinder; a communication groove formed at the lower part thereof between the elongated suction hole and the first discharge side opening/closing hole, the communication groove communicating with the second discharge side opening/closing hole and opposite ends of the communication groove being closed; and a suction guide disposed between the elongated suction hole and the communication groove. Also, the cylinder includes an upper open groove disposed between the refrigerant inlet port thereof and the refrigerant outlet port thereof, the upper open groove being opposite to the communication groove of the actuator.
The above and other objects, features and other advantages of the present invention will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings, in which:
Now, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.
As shown in
The valve body 1 has a valve inlet port 11, which corresponds to the refrigerant inlet port of the cylinder, and a valve outlet port 12, which corresponds to the refrigerant outlet port of the cylinder. Under the valve inlet port 11 and the valve outlet port 12 is disposed an actuating groove 13, which is opened at one side thereof.
The actuator 3 is disposed in the actuating groove 13. The actuator 3 is linearly reciprocated, as the solenoid 2 is operated, to allow or interrupt communication between the refrigerant inlet port of the cylinder and the valve inlet port 11 and between the refrigerant outlet port of the cylinder and the valve outlet port 12. When the communication is interrupted between the refrigerant inlet port of the cylinder and the valve inlet port 11 and between the refrigerant outlet port of the cylinder and the valve outlet port 12, compression is performed in the cylinder. When the communication is allowed between the refrigerant inlet port of the cylinder and the valve inlet port 11 and between the refrigerant outlet port of the cylinder and the valve outlet port 12, on the other hand, compression is not performed in the cylinder.
According to the present invention, the actuator 3 may take various shapes, which will be described hereinafter in detail with reference to the accompanying drawings.
When the actuator 3 is moved forward by the solenoid 2, as shown in
Consequently, refrigerant gas introduced into the valve body 1 through the valve inlet port 11 flows along the actuating groove 13 and the communication groove 32, and then flows backward into the cylinder 100 through a refrigerant inlet port 100a of the cylinder 100. The refrigerant gas introduced into the cylinder 100 through the refrigerant inlet port 100a of the cylinder 100 is compressed in the cylinder 100, and is then discharged out of the cylinder 100 through the refrigerant outlet port 100b of the cylinder 100, the discharge side opening/closing hole 31 of the actuator 3, and the valve outlet port 12. In this way, compression in the compression chamber of the cylinder 100 is accomplished.
When the actuator 3 is moved rearward by the solenoid 2, as shown in
Consequently, refrigerant gas introduced into the cylinder 100 through the valve inlet port 11 and the refrigerant inlet port 100a of the cylinder 100 is compressed in the cylinder 100. However, the compressed refrigerant is not discharged out of the cylinder 100. Specifically, the compressed refrigerant is circulated along the actuating groove 13 of the valve body 1 through the communication groove 32. As a result, the refrigerant inlet port 100a of the cylinder 100 communicates with the refrigerant outlet port 100b of the cylinder 100.
When the actuator 4 is moved rearward by the solenoid 2, as shown in
Consequently, refrigerant gas introduced into the communication groove 43 of the actuator 4 through the valve inlet port 11 flows along the communication groove 43, and then flows backward into the cylinder 100 through the refrigerant inlet port 100a of the cylinder 100. The refrigerant gas introduced into the cylinder 100 through the refrigerant inlet port 100a of the cylinder 100 is compressed in the cylinder 100, and is then discharged out of the cylinder 100 through the refrigerant outlet port 100b of the cylinder 100, the discharge side opening/closing hole 41 of the actuator 4, and the valve outlet port 12. In this way, compression in the compression chamber of the cylinder 100 is accomplished.
When the actuator 4 is moved forward by the solenoid 2, as shown in
The refrigerant gas introduced into the cylinder 100 is compressed in the cylinder 100. However, the compressed refrigerant is not discharged out of the cylinder 100. Specifically, the compressed refrigerant is circulated along the communication groove 43 of the actuator 4. As a result, the refrigerant inlet port 100a of the cylinder 100 communicates with the refrigerant outlet port 100b of the cylinder 100.
When the actuator 5 is moved forward by the solenoid 2, as shown in
Consequently, refrigerant gas introduced into the communication groove 51 of the actuator 5 through the valve inlet port 11 and the suction side opening/closing hole 52 flows along the communication groove 51, and then flows backward into the cylinder 100 through the refrigerant inlet port 100a of the cylinder 100. The refrigerant gas introduced into the cylinder 100 through the refrigerant inlet port 100a of the cylinder 100 is compressed, and is then discharged out of the cylinder 100 through the refrigerant outlet port 100b of the cylinder 100, the discharge side opening/closing hole 54 of the actuator 5, and the valve outlet port 12. In this way, compression in the compression chamber of the cylinder 100 is accomplished.
When the actuator 5 is moved rearward by the solenoid 2, as shown in
Consequently, refrigerant gas introduced into the cylinder 100 through the refrigerant inlet port 100a of the cylinder 100 is compressed, and is then discharged out of the cylinder 100 through the refrigerant outlet port 100b of the cylinder 100, the communication hole 53 of the actuator 5, and the valve outlet port 12. While introduction of the refrigerant gas through the valve inlet port 11 is interrupted, the refrigerant gas in the cylinder 100 is repetitively circulated and discharged through the communication groove 51 of the actuator 5. In this way, the refrigerant inlet port 100a of the cylinder 100 communicates with the refrigerant outlet port 100b of the cylinder 100 through the communication groove 51 of the actuator 5.
When the actuator 6 is moved rearward by the solenoid 2, as shown in
Consequently, refrigerant gas is introduced into the cylinder 100 through the valve inlet port 11, the elongated suction hole 62, and the refrigerant inlet port 100a of the cylinder 100. The refrigerant gas introduced into the cylinder 100 is compressed, and is then discharged out of the cylinder 100 through the refrigerant outlet port 100b of the cylinder 100, the discharge side opening/closing hole 61 of the actuator 6, and the valve outlet port 12. In this way, compression in the compression chamber of the cylinder 100 is accomplished.
When the actuator 6 is moved forward by the solenoid 2, as shown in
Also, the suction guide 65 of the actuator 6 is placed in the upper open groove 64 of the cylinder 100. As a result, the communication groove 63 communicates with the elongated suction hole 62 through the upper open groove 64 of the cylinder 100. Consequently, the refrigerant gas introduced into the communication groove 63 is introduced into the elongated suction hole 62 through the upper open groove 64. In this way, the refrigerant inlet port 100a of the cylinder 100 communicates with the refrigerant outlet port 100b of the cylinder 100.
When the compression is performed as shown in
At the actuator 7, under the suction side opening/closing hole 72, is formed a first communication groove 74, which communicates with the suction side opening/closing hole 72. Opposite ends of the first communication groove 74 are closed. At the actuator 7, under the communication hole 73, is formed a second communication groove 75, which communicates with the communication hole 73. Opposite ends of the second communication groove 75 are also closed. Between the first communication groove 74 and the second communication groove 75 is disposed a suction guide 77. Correspondingly, the cylinder 100 has an upper open groove 76, which is disposed between the refrigerant inlet port 100a of the cylinder 100 and the refrigerant outlet port 100b of the cylinder 100. The upper open groove 76 of the cylinder 100 is opposite to the first communication groove 74 and the second communication groove 75.
When the actuator 7 is moved rearward by the solenoid 2, as shown in
At this time, the suction guide 77 of the actuator 7 serves to prevent low-temperature refrigerant gas introduced through the suction side opening/closing hole 72 from flowing to the refrigerant outlet port 100b of the cylinder 100, through which compressed high-temperature refrigerant gas is discharged. The second communication groove 75, which is disposed between the suction side opening/closing hole 72 and the discharge side opening/closing hole 71, does not communicate with the refrigerant inlet port 100a of the cylinder 100 as well as the refrigerant outlet port 100b of the cylinder 100.
Consequently, refrigerant gas is introduced into the cylinder 5 through the valve inlet port 11, the suction side opening/closing hole 72 and the first communication groove 74 of the actuator 7, and the refrigerant inlet port 100a of the cylinder 100, and is then compressed in the cylinder 100. The compressed refrigerant gas is discharged out of the cylinder 100 through the refrigerant outlet port 100b of the cylinder 100, the discharge side opening/closing hole 71 of the actuator 7, and the valve outlet port 12. In this way, compression in the compression chamber of the cylinder 100 is accomplished.
When the actuator 7 is moved forward by the solenoid 2, as shown in
Also, the discharge side opening/closing hole 71 of the actuator 7 is not aligned with the valve outlet port 12 and the refrigerant outlet port 100b of the cylinder 100. However, the communication hole 73 and the second communication groove 75 communicate with the valve outlet port 12 and the refrigerant outlet port 100b of the cylinder 100. Also, the suction guide 77, which is disposed between the first communication groove 74 and the second communication groove 75, is placed in the middle of the upper open groove 76 of the cylinder 100. As a result, the first communication groove 74 communicates with the second communication groove 75.
Consequently, the refrigerant gas introduced into the cylinder 100 is compressed while further introduction of refrigerant gas is interrupted, and is then discharged out of the cylinder 100 through the refrigerant outlet port 100b of the cylinder 100, the communication hole 73 of the actuator 7, and the valve outlet port 12. At this time, some of the compressed refrigerant gas is introduced into the refrigerant inlet port 100a of the cylinder 100 through the second communication groove 75 of the actuator 7, the upper open groove 76 of the cylinder 100, and the first communication groove 74 of the actuator 7. Consequently, the refrigerant inlet port 100a of the cylinder 100 communicates with the refrigerant outlet port 100b of the cylinder 100.
When the actuator 8 is moved rearward by the solenoid 2, as shown in
Consequently, refrigerant gas is introduced into the cylinder 100 through the valve inlet port 11, the elongated suction hole 82, and the refrigerant inlet port 100a of the cylinder 100. The refrigerant gas introduced into the cylinder 100 is compressed, and is then discharged out of the cylinder 100 through the refrigerant outlet port 100b of the cylinder 100, the first discharge side opening/closing hole 81 of the actuator 8, and the valve outlet port 12. In this way, compression in the compression chamber of the cylinder 100 is accomplished.
When the actuator 8 is moved forward by the solenoid 2, as shown in
Also, the suction guide 85 of the actuator 8 is placed in the upper open groove 84 of the cylinder 100. As a result, the communication groove 83 communicates with the elongated suction hole 82 through the upper open groove 84 of the cylinder 100.
Consequently, the refrigerant gas discharged through the refrigerant outlet port 100b of the cylinder 100 is introduced into the second discharge side opening/closing hole 86 and the communication groove 83 of the actuator 8, and is then introduced into the elongated suction hole 82 through the upper open groove 84 of the cylinder 100. In this way, the refrigerant inlet port 100a of the cylinder 100 communicates with the refrigerant outlet port 100b of the cylinder 100.
When the compression is performed as shown in
The smart control valve for compressors according to the sixth preferred embodiment of the present invention is characterized in that the suction pressure is applied to the discharge reed valve 14 through the second discharge side opening/closing hole when no-load operation of the compressor is performed, and therefore, operability of the valve is improved, and in that the discharge reed valve 14 is operated by the difference between the suction pressure applied to the discharge reed valve 14 and the discharge pressure from the discharge reed valve 14, and therefore, the sealing of the discharge reed valve 14 is improved.
As shown in
The drive unit 130 comprises: a rotor 131, through the center of which the crankshaft 140 longitudinally extends; and a stator 132 disposed around the rotor 131.
The compression unit 120 comprises: an orbiting scroll 121 connected to the crankshaft 140 at the lower part thereof and having an involute-shaped orbiting wrap 121a formed at the upper part thereof; and a stationary scroll 122 disposed on the orbiting scroll 121 and having a stationary wrap 122a formed at the lower part thereof. The orbiting wrap 121a of the orbiting scroll 121 is engaged with the stationary wrap 122a of the stationary scroll 122. As the orbiting scroll 121 performs an orbiting movement according to rotation of the crankshaft 140, refrigerant gas is compressed in a compression chamber defined between the orbiting wrap 121a and the stationary wrap 122a.
A smart control valve S according to the present invention is mounted on the upper surface of the stationary scroll 122 of the scroll compressor for opening or closing a refrigerant inlet port 122b and a refrigerant outlet port 122c of the stationary scroll 122. By the opening or closing operation of the smart control valve S, communication or compression is accomplished in the compression chamber defined between the orbiting wrap 121a and the stationary wrap 122a. The refrigerant inlet port 122b and the refrigerant outlet port 122c are formed at the upper part of the stationary scroll 122. Specifically, the refrigerant outlet port 122c is formed at the center of the upper part of the stationary scroll 122. The refrigerant inlet tube 111 is vertically connected to the refrigerant inlet port 122b of the stationary scroll 122.
The compression and communication process in the scroll compressor having the smart control valve mounted therein is identical to the processes described above in connection with the smart control valves according to first to sixth preferred embodiments of the present invention. Therefore, a detailed description of the compression and communication process in the scroll compressor will not be given.
As shown in
The compression unit 220 comprises: a cylinder 221 having a compression chamber defined therein; and a roller 222 slidably and rotatably disposed in the cylinder 221. The roller 222 is connected to an eccentric part 240a formed at the rotary shaft 240 such that the roller 222 performs an eccentric rotation as the rotary shaft 240 is operated. Refrigerant introduced into the cylinder 221 through a refrigerant inlet port 224a is compressed by the eccentric rotation of the roller 222.
The drive unit 230 comprises: a rotor 231, through the center of which the rotary shaft 240 longitudinally extends; and a stator 232 disposed around the rotor 231 for generating a magnetic field. The rotary shaft 240 is supported by an upper flange 223, which is disposed above the cylinder 221, and a lower flange 224, which is disposed below the cylinder 221.
A smart control valve S according to the present invention is mounted on the lower surface of the lower frame 224 of the rotary compressor for opening or closing a refrigerant inlet port 224a and a refrigerant outlet port 224b formed at the lower flange 224. By the opening or closing operation of the smart control valve S, communication or compression is accomplished in the compression chamber of the cylinder 221.
The refrigerant inlet port 224a and the refrigerant outlet port 224b are formed at the lower part of the lower flange 224. Refrigerant gas discharged through the refrigerant outlet port 224b and the smart control valve S during compression is guided into the hermetically sealed container 210 through a discharge channel 221a vertically extending through the cylinder 221, and is then discharged out of the hermetically sealed container 210 through the refrigerant outlet tube 212.
The operation of the smart control valve S for opening and closing the refrigerant inlet port 224a and the refrigerant outlet port 224b of the lower flange 224 is identical to those described above in connection with the smart control valves according to first to sixth preferred embodiments of the present invention. Therefore, a detailed description of the operation of the smart control valve in the rotary compressor will not be given.
Meanwhile, the above-specified scroll compressor and rotary compressor are merely examples given to describe the present invention, and therefore, the present invention is limited to the above-specified scroll compressor and rotary compressor. Consequently, the present invention is applicable to any kinds of compressors so long as the refrigerant inlet port and the refrigerant outlet port are opened and closed to accomplish communication and compression in the compression chamber. Especially when the compressor has a plurality of compression chambers, i.e., inner and outer compression chambers, a pair of smart control valves may be mounted at the inner and outer compression chambers, respectively. For a twin compressor, i.e., a compressor having a plurality of compression units, which are vertically disposed, smart control valves may be mounted at the respective compression units.
According to the present invention, the capacity of the compressor is changed based on a pulse width modulation (hereinafter, referred to as “PWM”) control system. The PWM control serves to adjust a duty ratio of a pulse signal. Here, the duty ratio is a ratio of time (T(h)) for “High” signal to a period (T).
For example, a DC motor is operated when electric current is supplied to the DC motor, and stopped when electric current is not supplied to the DC motor. When the on and off operation of the DC motor is repetitively performed at short intervals, it seems that the DC motor is slowly operated.
When the compression and communication process in the compression chamber is periodically repeated using the smart control valve according to the present invention based on the above-mentioned control system, the capacity of the compressor is changed. If the duty ratio is 95%, compression is accomplished in the compression chamber approximately with the maximum compression efficiency of the compression unit. If the duty ratio is 50%, on the other hand, compression is accomplished in the compression chamber at approximately half the maximum compression efficiency of the compression unit.
As apparent from the above description, the present invention provides a smart control valve for compressors that is capable of easily accomplishing compression and communication in a compression chamber of a cylinder, without performing the repetitive on/off operation of the compressor, to change the capacity of the compressor. Consequently, the present invention has the effect of accomplishing economical efficiency of the compressor, reducing power consumption due to repetitive on/off operation of the compressor, preventing reduction in service life of the compressor due to premature wear of the parts of the compressor, and therefore, improving the performance and reliability of the compressor.
Although the preferred embodiments of the present invention have been disclosed for illustrative purposes, those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims.
Number | Date | Country | Kind |
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10-2004-0105659 | Dec 2004 | KR | national |
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Number | Date | Country | |
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20060127236 A1 | Jun 2006 | US |