KR100292516B1 - Linear compressor - Google Patents

Abstract

The present invention relates to a linear compressor, the present invention is a frame which is supported in a sealed container and the oil flow path is formed, a cylinder having an oil through hole is formed to communicate with the oil flow path is fixed to the frame, and is inserted into the cylinder At the same time, the piston is coupled to the linear motor and reciprocates in a straight line, and is formed in a negative manner on the sliding surface between the cylinder and the piston so as to communicate with the oil through-hole, thereby changing the volume change between the piston and the cylinder during the reciprocating movement of the piston. It is formed by a sliding portion which protrudes from the piston so as to receive a variable volume portion or a rear end face of the cylinder, which is in sliding contact with the outer circumferential surface of the cylinder, and an oil passage formed on the outer circumferential surface of the piston, In communication with the piston causing volume change It is connected to the variable volume through the variable volume, the oil flow path of the frame and the oil through hole of the cylinder, and the other end is installed to be immersed in the oil of the sealed container, and pumped by the pressure difference of the variable volume generated during the reciprocating movement of the piston. A device for supplying oil to the compression unit by including an oil guide member for guiding oil of the sealed container between the cylinder and the piston, and an oil valve mounted on the discharge side of the oil guide member to prevent backflow of the pumped oil. Simplification not only increases productivity, but also lowers the motor input for its operation, improving motor efficiency relative to the input.

Description

Linear Compressor {LINEAR COMPRESSOR}

The present invention relates to a linear compressor, and more particularly, to a linear compressor capable of supplying oil to a compression unit without using a separate oil feeder.

As is known, a linear compressor compresses a refrigerant by directly reciprocating a piston with a magnet and a coil in place of the crankshaft, an example of which is shown in FIG.

As shown in the drawing, the conventional linear compressor has a compression unit (C) installed in the transverse direction inside an airtight container (V) filled with oil on its bottom surface to suck, compress, and discharge refrigerant, and the compression unit (V). It is composed of an oil feeder (O) which is fixed to the outside and supplies oil.

The compression unit (C) includes a frame (1) installed inside the sealed container (V), a cylinder (2) inserted into a through hole formed in the center of the frame (1), and the inside of the cylinder (2). A piston 3 inserted and linearly reciprocated by driving of a linear motor (unsigned), and a discharge valve 4 for opening and closing the cylinder 2 in accordance with the reciprocating motion of the piston 3 are inserted. It comprises a discharge cover 5 is coupled to one side of the cylinder (3).

A first oil pocket 1b is formed on the inner circumferential surface of the through hole of the frame 1 and communicated with the discharge side of the oil feeder O by an oil inflow passage 1a, and a second oil is formed on the outer circumferential surface of the piston 3. The pocket 3a is formed, and the cylinder 2 has an oil through-hole 2a through which the first oil pocket 1b and the second oil pocket 3a communicate with each other. Through-holes of the outer circumferential surface and the frame 1 and the discharge cover 5 form an annular oil circulation path 1d communicating with the oil communication path 1c at the top of the first oil pocket 1b. At the lowest point of the oil circulation path 1d, an oil discharge hole 1e is formed so that the oil circulated in the oil circulation path 1d is returned to the sealed container V.

Meanwhile, the oil feeder O is inserted into the oil cylinder 21 attached to the bottom side of the compression unit C, and the oil cylinder 21 is inserted into the suction space S1 and the discharge space S2. The oil piston 22 to be partitioned, first and second oil springs 23A and 23B which elastically support both ends of the oil piston 22 from the oil cylinder 21, and the first and second oil springs ( An oil suction cover 24 and an oil discharge cover 25 for supporting the other ends of the 23A and 23B and fixing both ends of the oil cylinder 21 to the compression unit C, and the oil piston 22 The oil intake valve 26 is supported by the second oil spring 23B on the outlet side of the oil discharge valve 27, and the oil discharge valve 27 is provided on the outlet side of the oil cylinder 21.

The oil piston 22 is inserted such that its outer circumferential surface is in sliding contact with the inner circumferential surface of the oil cylinder 21, and an oil passage 22a through which the inlet and outlet of the oil cylinder 21 communicates is formed therein. .

The oil intake valve 26 is formed in a spiral type and is inserted into the oil cylinder 21 and tightly supported by the second oil spring 23B at the outlet end of the oil piston 22, while the oil discharge valve Reference numeral 27 is formed in a rectangular shape and closely adhered to the discharge side outer surface of the oil cylinder 21, and is supported by the oil discharge cover 25.

In the drawings, reference numeral 6 denotes a valve spring, and 7 denotes a suction valve.

The oil supply device of the conventional linear compressor configured as described above is operated as follows.

That is, the compression unit C vibrates in the lateral direction together with the magnet assembly (unsigned) during linear reciprocation of the magnet assembly (unsigned), which is the mover of the linear motor, and the vibration is the compression unit C. It is delivered to the oil feeder (O) fixed to the reciprocating movement, in which the oil piston (22) is inserted into the inside of the oil cylinder (21) by the inertial force against the reciprocating motion of the oil cylinder (21) The oil is absorbed and discharged.

In this way, the oil pumped by the oil feeder (O) is introduced into the first oil pocket (1b) through the oil inlet flow path (1a) to cool the heat generated in the outer peripheral surface and the linear motor of the cylinder (2) (2a) flows into the second oil pocket (3a), flows into the second oil pocket (3a) to lubricate the sliding portion between the cylinder (2) and the piston (3), and then again the first oil pocket ( 1b) and the oil communication passage 1c flow into the oil circulation passage 1d, and the oil introduced into the oil circulation passage 1d circulates while cooling the above-described cylinder 2 and the discharge cover 4, Through the oil discharge hole (1e) is returned to the sealed container (V).

Here, the operation of pumping oil by the oil feeder will be described in more detail as shown in FIGS. 2A and 2B.

First, when the oil cylinder 21 moves in the "P" direction of the drawing, the oil piston is moved in the opposite direction with respect to the oil cylinder to push out the oil filled in the discharge space while the oil cylinder Oil is introduced into the gap between the 21 and the oil suction cover 24 to fill the suction space. At this time, the oil intake valve 26 is closed while closing the oil passage 22a of the oil piston 22, while the oil discharge valve 27 is flipped to open the discharge side of the oil cylinder 21.

On the other hand, when the oil cylinder 21 is moved in the "Q" direction of the drawing, the oil piston 22 is an effect of moving in the opposite direction with respect to the oil cylinder 21, the pressure of the discharge space is before ( The oil is discharged to the compression unit (C) in the process, and the oil of the suction space (S1) is moved to the discharge space (S2) while being relatively low pressure compared to the suction space. At this time, the first oil spring 23A is compressed while the second oil spring 23B is compressed, and the oil intake valve 26 is opened while the oil discharge valve 27 is returned. The discharge side was closed to prevent backflow of oil.

However, in the oil supply apparatus of the conventional linear compressor as described above, as described above, a separate oil feeder O provided with the oil piston 22, the oil springs 23A and 23B, the oil suction valve 26, and the like. To be provided, which has a problem that the number of parts is difficult to manufacture and assembly.

In addition, the oil feeder (O) uses the vibration of the compression unit (C). In order to vibrate the oil feeder (O), the input applied to the motor is increased, thereby reducing the motor efficiency compared to the input.

Accordingly, the present invention has been made in view of the problems of the oil supply device of the conventional linear compressor as described above, and not only improves productivity by simplifying the device for supplying oil to the compression unit, but also improves the performance of the motor for its operation. An object of the present invention is to provide a linear compressor that can lower the input to improve the motor efficiency compared to the input.

1 is a longitudinal sectional view showing an example of a conventional linear compressor.

Figures 2a and 2b is a longitudinal sectional view showing the operation of supplying oil in a conventional linear compressor.

Figure 3 is a longitudinal sectional view showing an example of the linear compressor provided with the oil supply structure of the present invention.

Figures 4a and 4b is a longitudinal sectional view showing the operation of supplying oil in the linear compressor of the present invention.

Figure 5 is a longitudinal sectional view showing a modification to the oil supply structure of the linear compressor of the present invention.

6A and 6B are sectional views showing examples of the "A-A" part in FIG.

Figures 7a and 7b is a longitudinal sectional view showing the operation of supplying oil in the linear compressor of the present invention.

Explanation of symbols on the main parts of the drawings

110: cylinder 111: oil through hole

120: piston 121: flange

122: sliding protrusion 123a, 123b: oil passage

130: oil supply container 140: oil valve

150,160: oil suction and discharge cover 200,300: variable volume part

In order to achieve the object of the present invention, the oil frame is formed so that the oil flow path is formed to be elastically supported inside the sealed container and the oil of the sealed container is circulated, and the oil through hole is formed in communication with the oil flow path of the frame A cylinder fixed to the cylinder, a piston which is slidably inserted into the cylinder and simultaneously coupled to a linear motor to reciprocate linearly, and is formed in a negative manner on a sliding surface between the cylinder and the piston so as to communicate with the oil through hole of the cylinder When the piston is reciprocating, the variable volume portion causing volume change between the piston and the cylinder and the variable volume portion communicate with the variable volume through the oil flow path of the frame and the oil through hole of the cylinder, and the other end is installed to be immersed in the oil of the sealed container. Mill pumped by the pressure difference in the variable volume generated during the reciprocating motion of the piston And an oil guide member for guiding the fluid of the container between the cylinder and the piston, the linear compressor including an oil valve that is attached to the discharge side of the oil guide member prevents the reverse flow of the pumped oil is provided.

Alternatively, the piston is formed by a sliding protrusion protruding from the piston to receive the rear end surface of the cylinder and to be in sliding contact with the outer circumferential surface of the cylinder, and communicate with the oil through-hole of the cylinder by an oil passage formed on the outer circumferential surface of the piston. There is provided a linear compressor including a variable volume portion that causes a volume change during a reciprocating motion.

Hereinafter, the linear compressor according to the present invention will be described in detail based on the embodiment shown in the accompanying drawings.

3 is a longitudinal sectional view showing an example of a linear compressor provided with an oil supply structure of the present invention, and FIGS. 4A and 4B are longitudinal sectional views showing an operation of supplying oil in the linear compressor of the present invention.

As shown therein, the linear compressor according to the present invention comprises an airtight container V filled with oil on its bottom surface, and a compression unit C for sucking, compressing, and discharging refrigerant inside the airtight container V. The frame 1, the cylinder 110, the piston 120, the linear motor (unsigned), the discharge cover 5, and the like are provided in the transverse direction.

An oil inflow passage 1a is formed on the inner circumferential surface of the through hole of the frame 1 to communicate the discharge side of the oil supply cylinder 130, which will be described later, and communicates with an end portion of the oil inflow passage 1a. 1b) is formed between the frame 1 and the cylinder 110, the closed container (V) on the outer peripheral surface of the piston 120 by using the pressure difference according to the volume change during the linear reciprocating motion of the piston 120 A variable volume part 200 is formed to pump oil filled in the bottom surface of the cylinder, and an oil through hole 111 for communicating the first oil pocket 1b and the variable volume part 200 is formed in the cylinder 110. And the annular oil communicated by the oil communication passage 1c to the uppermost point of the first oil pocket 1b by the outer circumferential surface of the cylinder 100, the through hole of the frame 1, and the discharge cover 5. A circulation path 1d is formed, and at the lowest point of the oil circulation path 1d, the oil circulated in the oil circulation path 1d described above. Yi oil drain (1e) such that returns to the closed container (V) is formed.

The variable volume part 200 is formed to be intaglio so that the inner circumferential surface of the cylinder 110 and the outer circumferential surface of the piston 120 are engaged with each other.

The oil supply container 130 is formed in a hollow cylinder to be fixed to the lower portion of the frame 1 so as to be immersed in the oil of the sealed container (V), the discharge side of the conventional rectangular oil valve 140 is It is mounted between the oil discharge cover 150 to open and close the oil supply container 130.

In the drawings, the same reference numerals are given to the same parts as in the prior art.

In the drawings, reference numeral 4 denotes a discharge valve, 6 a valve spring, 7 a suction valve, and 160 a oil suction cover.

The linear compressor equipped with the oil supply structure according to the present invention configured as described above is operated as follows.

That is, when the magnet assembly (unsigned), which is the mover of the linear motor, performs a linear reciprocating motion, the piston 120 integrated in the magnet assembly also reciprocates in a straight line in the cylinder 110 and sucks in refrigerant gas. To repeat the compression discharge process.

At this time, the variable volume portion 200 provided between the outer peripheral surface and the inner peripheral surface of the cylinder 110 during the reciprocating motion of the piston 120 causes a pressure change while causing a pressure change, the closed by the pressure difference The oil filled in the bottom surface of the container V is sucked along the oil inflow passage 1a and filled in the variable volume part 200 between the cylinder 110 and the piston 120, and the variable volume part 200 The oil filled in lubricates the sliding portion between the cylinder 110 and the piston 120 and then cools the compression unit C, and then returns to the sealed container V again.

Here, the process of pumping the oil of the closed container in more detail as follows.

First, as shown in FIG. 4A, when the piston 120 moves backward, the volume of the variable volume part 200 is increased and the pressure is relatively lower than that of the oil supply container 130. 140 is opened, which causes the oil to be sucked from the oil supply barrel 130 submerged in the oil so that the variable volume portion is provided through the oil inflow passage 1a and the first oil pocket 1b and the inflow side oil through hole 111. Flows into 200. At this time, the oil in the first oil pocket (1b) cools the heat generated in the compression unit (C) while flowing through the outer peripheral surface of the cylinder 110, the first oil pocket (1b) is not provided as necessary It may be.

Next, as shown in FIG. 4b, when the piston 120 moves forward, the volume of the variable volume 200 decreases and the pressure is relatively higher than that of the oil supply container 130. 140 is closed, and the oil of the variable volume part 200 is prevented from flowing back into the oil supply container 130 by the closed oil valve 140, while the oil discharge hole 1e is opened. The oil of the variable volume part 200 is introduced into the oil circulation path 1d through the first oil pocket 1b and the oil communication path 1c through the outflow side oil through hole 111 of the cylinder 110. The oil introduced into the oil circulation path 1d is cooled to the compression unit C again and then returned to the sealed container V through the oil discharge hole 1e.

The valve of the oil guide means may be replaced with a fluid diode (not shown).

On the other hand, when there is a modification of the oil supply structure according to the present invention is as follows.

In the above-described example, the variable volume part 200 was formed between the cylinder 110 and the piston 120. However, in the present modified example, the rear end of the cylinder 110 is opposed to the piston 110 as shown in FIG. The annular sliding portion 122 having the variable volume part 300 is formed on the flange portion 121 of the cylinder 120 together with the rear end surface of the cylinder 110. During the reciprocating motion, the rear end of the cylinder 110 enters into the sliding portion 122 and causes volume change.

Here, the oil through-hole 111 of the cylinder 110 is formed in the intermediate position of the cylinder 110 in the structure of the compression unit (C), in order to communicate the oil through-hole 110 and the variable volume portion 300. Oil passages 123a and 123b as shown in FIGS. 6a and 6b should be formed on the outer circumferential surface of the piston 120.

In this modified example, as shown in Figure 7a and 7b, the oil inlet flow path (1a) and the first oil pocket (1b) and the inlet oil from the oil supply cylinder 130 at the time of retraction of the piston 120 The oil flowing into the second oil pocket 124 through the through hole 111 flows into the variable volume part 300 along the oil passages 123a and 123b of the piston 120 and then moves forward of the piston 120. The second oil pocket 124 and the outflow side oil through-hole 111 and the first oil pocket 1b and the oil communication passage 1c through the oil passages 123a and 123b from the variable volume unit 300 again. After entering the oil circulation path (1d) to cool the compression unit (C), a series of processes to return back to the sealed container (V) through the oil discharge hole (1e) is repeated.

In this way, the oil supply structure for supplying oil to the compression unit is conventionally composed of an oil cylinder, an oil piston, a first and a second oil spring and an oil intake valve, an oil discharge valve, and the like. Since the size of the valve is difficult to manufacture and assemble, and the compression unit is heavy with a plurality of parts, the input of the motor increases, but in the present invention, the oil piston, the first and second oil springs, and the oil suction valve are Instead of removing it, a kind of oil pump is formed between the cylinder and the piston of the compression unit, thereby reducing the number of parts for the oil supply device, making it easier to manufacture and assemble, and improving the motor efficiency compared to the input by reducing the input of the motor. do.

As described above, the oil supply structure of the linear compressor according to the present invention includes a cylinder and a cylinder for supplying the oil of the sealed container to the compression unit by using the pressure difference according to the volume change of the oil pumping space during the linear reciprocating motion of the piston. A variable volume for pumping oil is formed between the pistons inserted in the cylinder and linearly reciprocating, and one end communicates with the variable volume, while the other end is immersed in oil filled in the bottom of the sealed container. By forming and configuring, it is possible to simplify the device for supplying oil to the compression unit to improve productivity, and to lower the input of the motor for its operation, thereby improving the motor efficiency compared to the input.

Claims (2)

A frame which is elastically supported in the sealed container and is formed with an oil flow path for circulating oil in the sealed container, an oil through hole is formed to communicate with the oil flow path of the frame, and is fixed to the frame; A piston which is inserted and coupled to a linear motor to reciprocate linearly, A variable volume part which is formed in an inclined correspondence with each other on the sliding surface between the cylinder and the piston so as to communicate with the oil through hole of the cylinder, causing a volume change between the piston and the cylinder during the reciprocating movement of the piston; The oil in the sealed container which is connected to the variable volume through the oil flow path of the frame and the oil through hole of the cylinder, and the other end is installed to be immersed in the oil of the sealed container and pumped by the pressure difference of the variable volume generated during the reciprocating motion of the piston. And an oil guide member for guiding the oil between the cylinder and the piston, and an oil valve mounted on the discharge side of the oil guide member to prevent backflow of the pumped oil. A frame which is elastically supported in the sealed container and is formed with an oil flow path for circulating oil in the sealed container, an oil through hole is formed to communicate with the oil flow path of the frame, and is fixed to the frame; A piston which is inserted and coupled to a linear motor to reciprocate linearly, It is formed by a sliding protrusion protruding from the piston to receive the rear end surface of the cylinder and to make sliding contact with the outer peripheral surface of the cylinder, and is also communicated with the oil through hole of the cylinder by an oil passage formed on the outer peripheral surface of the piston to reciprocate the piston. Variable volume part which causes volume change during exercise, The oil in the sealed container which is connected to the variable volume through the oil flow path of the frame and the oil through hole of the cylinder, and the other end is installed to be immersed in the oil of the sealed container and pumped by the pressure difference of the variable volume generated during the reciprocating motion of the piston. And an oil guide member for guiding the oil between the cylinder and the piston, and an oil valve mounted on the discharge side of the oil guide member to prevent backflow of the pumped oil.