KR101463832B1 - Reciprocating compressor and refrigerating machine having the same - Google Patents

Abstract

The present invention relates to a reciprocating compressor. The ball bearing can be easily and stably installed on the thrust surface between the cylinder block and the crankshaft so that the efficiency of the compressor can be improved. Further, as the ball bearing is inserted into the thrust surface, the moment arm is shortened to reduce the frictional loss on the journal bearing surface, thereby improving the energy efficiency of the compressor and the refrigerating machine having the same. Since the oil hole is covered by the journal bearing surface of the cylinder block, the amount of oil leaking to the thrust surface can be reduced even though the ball bearing is applied, thereby effectively lubricating the cam portion and the connecting rod and effectively cooling the rolling portion So that the efficiency of the compressor and the refrigeration apparatus having the compressor can be further increased.

Reciprocating compressor, thrust, ball bearing, bearing insert groove

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reciprocating compressor,

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reciprocating compressor, and more particularly to a reciprocating compressor in which a ball bearing is installed on a thrust surface between a cylinder block and a crankshaft.

Generally, a hermetic compressor is a compressor that includes a power transmission unit that generates power in a sealed container and a compression unit that operates by receiving the power of the power transmission unit. The hermetic compressor may be classified into a reciprocating type, a rotary type, a vane type, and a scroll type depending on a method of compressing a refrigerant as a compressible fluid.

In the reciprocating compressor, a crankshaft is coupled to a rotor of a transmission portion, a connecting rod is coupled to the crankshaft, and a piston coupled to the connecting rod linearly reciprocates within the cylinder to compress the refrigerant .

In the reciprocating compressor, the shaft portion of the crankshaft is inserted into the cylinder block and radially supported, and the eccentric mass portion is also supported on the cylinder block in the axial direction. Accordingly, since the journal bearing surface and the thrust bearing surface are formed between the crankshaft and the cylinder block, it is important to reduce the friction loss in the journal bearing surface and the thrust bearing surface to the minimum, which is an important factor for improving the energy efficiency of the compressor .

To this end, an oil passage is formed in the conventional crankshaft so that oil pumped from the oil feeder is uniformly supplied to the respective bearing surfaces through the oil passage.

However, in the conventional reciprocating compressor, there is a limit in reducing the friction loss due to the surface contact of the thrust surface, and a method of installing a separate bearing such as a ball bearing so that the thrust surface can be in point contact is known.

However, in the above-described conventional reciprocating compressor, if at least a part of a bearing provided on a thrust surface between the cylinder block and the crankshaft moves in the radial direction, the assembling operation may become difficult or, There is a problem that noise or damage is caused by obstructing the operation or colliding with the crankshaft or the like.

In addition, by providing a separate bearing such as a ball bearing on the thrust surface, the gap between the thrust surfaces is increased by the height of the bearing to increase the moment, thereby reducing the compressor efficiency. Which is excessively discharged through the ball bearings, can not be lifted up to the upper end of the crankshaft, resulting in a severe frictional loss between the connecting rod and the compressor.

The present invention solves the problems of the conventional reciprocating compressor as described above, and it is an object of the present invention to provide a reciprocating compressor which can be easily assembled when the ball bearing is installed on the thrust surface, Which is an object of the present invention.

In addition, a bearing member such as a ball bearing is provided between the thrust surfaces to reduce the axial friction loss between the crankshaft and the cylinder block, reduce the moment due to the gas force in the cylinder, and smoothly supply the oil to the cam portion, It is an object of the present invention to provide an improved reciprocating compressor and a refrigerating machine having the same.

In order to solve the object of the present invention, there is provided a cylinder block in which a bearing hole is formed to form a journal bearing surface; A crankshaft formed with a plate-like extension portion wider than the bearing hole of the cylinder block and inserted in the bearing hole of the cylinder block and supported in the radial direction; And a bearing assembly installed between a thrust surface around the bearing hole of the cylinder block and a thrust surface of the crank shaft opposed thereto and axially supporting the crank shaft with respect to the cylinder block, There is provided a reciprocating compressor in which a bearing restraining portion is formed on at least one of thrust surfaces of the crankshaft so as to confine at least a part of the bearing assembly in a radial direction.

In addition, a crankshaft for transmitting a rotational force is supported in the cylinder block in the radial direction and the axial direction, and the connecting rod is engaged with the crankshaft to convert the rotational motion into a linear motion, and the piston coupled to the connecting rod reciprocates Wherein at least one oil passage is formed in the crankshaft, at least one oil groove is formed on an outer circumferential surface of the crankshaft, and the oil passage and the oil groove are at least one An oil inlet hole is formed in the oil groove communicating with the thrust face of the cylinder block and the thrust face of the crankshaft in the oil groove, and at least a part of the oil inlet hole Lt; RTI ID = 0.0 > a < / RTI > journal bearing surface of the cylinder block There is provided a reciprocating compressor.

In addition, A condenser connected to a discharge side of the compressor; An expander connected to the condenser; And an evaporator connected to the inflator and connected to the suction side of the compressor, wherein the compressor is provided with a bearing assembly axially supporting the cylinder block and the crankshaft, and a part of the bearing assembly is connected to the crankshaft And the other is supported in a radial direction by a bearing restricting portion provided in the cylinder block and an oil inflow hole for guiding the oil from the inside to the outside of the crankshaft is formed to be covered by the journal bearing surface Is provided.

The reciprocating compressor according to the present invention and the refrigerating machine using the same can easily and stably install the ball bearing on the thrust surface between the cylinder block and the crankshaft, thereby improving the efficiency of the compressor. As the ball bearing is inserted into the thrust surface, the moment arm is shortened to reduce the frictional loss on the journal bearing surface, thereby improving the energy efficiency of the compressor and the refrigerating machine having the same. As the oil inlet hole for guiding the oil from the inside to the outside of the crankshaft is covered by the journal bearing surface of the cylinder block, the amount of leakage of the oil to the axially facing surface can be reduced even though the ball bearing is applied, It is possible to effectively lubricate the cam portion and the connecting rod and effectively cool the rolling portion, thereby further improving the efficiency of the compressor and the refrigerating machine equipped therewith.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, a reciprocating compressor according to the present invention and a refrigerator having the same will be described in detail with reference to the accompanying drawings.

1, a reciprocating compressor according to the present invention includes a transmission unit 100 installed inside a hermetically sealed container 1 and performing a rotary motion, And a compression unit 200 that receives the rotational force of the eccentric shaft 100 and compresses the refrigerant.

The constant current motor 100 may be a constant-speed motor that performs only forward rotation, a constant-speed motor that is capable of forward rotation and reverse rotation, or an inverter motor. The power transmission unit 100 includes a stator 110 which is supported by a cylinder block 210 to be described later and is installed in a hermetically sealed container 1, Electrons.

The compression unit 200 includes a cylinder block 210 having a cylinder 211 to be compressed and supported by the closed container 1 and a cylinder block 210 inserted into the cylinder block 210, A crankshaft 220 coupled to the rotor 120 of the transmission unit 100 for transmitting rotational force and a connecting rod rotatably coupled to the crankshaft 220 to convert rotational motion into linear motion A piston 240 rotatably coupled to the connecting rod 230 to compress the refrigerant while linearly reciprocating in the cylinder 211 and a piston 240 coupled to a front end of the cylinder block 210, A valve assembly 250 having a valve and a discharge valve; a suction muffler 260 coupled to a suction side of the valve assembly 250; a discharge cover 270 coupled to receive a discharge side of the valve assembly 250; And a discharge port 270 communicating with the discharge cover 270, It comprises a discharge muffler (280) for attenuating the discharge noise of the refrigerant.

The reciprocating compressor according to the present invention as described above is characterized in that when power is applied to the stator 110 of the electromotive unit 100, the rotor 120 is rotated by the interaction force between the stator 110 and the rotor 120, The connecting rod 230 coupled to the cam portion 223 of the crankshaft 220 performs a swing motion and the piston (not shown) coupled to the connecting rod 230 rotates together with the crankshaft 220, The refrigerant discharged from the discharge cover 270 is discharged to the refrigerating cycle through the discharge muffler 280. The refrigerant discharged from the discharge cover 270 flows through the discharge muffler 280, And repeats a series of processes.

At the same time, the crankshaft 220 rotates while the oil feeder O provided at the lower end of the crankshaft 220 pumps the oil stored in the low-oil portion of the closed vessel 1, And is supplied to each sliding surface while a part thereof is scattered at the upper end of the crankshaft 220 to cool the transmission portion 100. [

Here, the configuration of the crankshaft for absorbing the oil stored in the low oil portion of the hermetically sealed container is as follows.

2, the crankshaft 220 is coupled to the rotor 120 and inserted into the bearing hole 212 of the cylinder block 210 to radially move the cylinder block 210 An eccentric mass portion 222 which is eccentrically formed in the shape of a fan or eccentrically circular flange on the upper end of the shaft portion 221 to form a plate-like extension portion; And a cam portion 223 which is formed eccentrically with respect to the shaft portion 221 and into which the connecting rod 230 is rotatably inserted.

The shaft portion 221 is formed with a first journal bearing surface 229a and a second journal bearing surface 229b at a predetermined interval on the outer circumferential surface corresponding to the journal bearing surface 215 of the bearing hole 212. [ The first oil passage 225a is formed to extend from the lower end to the upper end of the shaft portion 221 so as to be slightly inclined in the axial direction or the axial direction and to have a predetermined depth from the upper end of the cam portion 223 to the upper portion of the shaft portion 221 And the second oil passage 225b is formed in the axial direction. The first oil passage 225a and the second oil passage 225b are formed so as not to communicate with each other.

Oil is guided to the second journal bearing surface 229b of the crankshaft 220 in the middle of the first oil passage 225a, that is, at a portion corresponding to the lower half of the journal bearing surface 215 of the bearing hole 212 And a first oil groove 226a having a predetermined inclination angle from the first oil outflow hole 226a to a predetermined height, that is, substantially the end of the water hole 212, Is formed in a spiral shape. An oil inflow hole 226c communicating with the second oil passage 225b is formed at an end of the first oil groove 226b and a middle portion of the second oil passage 225b, A second oil outlet hole 226d for guiding the oil, which is sucked through the second oil passage 225b, to the outer circumferential surface is formed. A second oil groove 226e having a predetermined inclination angle from the second oil outlet hole 226d to the upper end of the cam portion 223 is formed in a spiral shape.

The oil pumped by the oil feeder O is sucked through the first oil passage 225a and a part of the oil is pumped through the first oil outlet hole 226a into the first oil groove 226b. The oil guided to the first oil groove 226b is lifted up on the first oil groove 226b and the second journal bearing surface 229b and the first journal bearing surface 229a of the crankshaft 220 Lubrication in sequence.

Then, the oil lubricated with the journal bearing surfaces 229a and 229b flows into the second oil passage 225b through the oil inlet hole 226c and is again picked up. And then flows into the second oil groove 226e through the second oil groove 226d to lubricate the cam portion 223 of the crankshaft 220. [

Here, the crankshaft is inserted into the bearing hole provided in the cylinder block and is supported in the radial direction while being rotated, and is also supported in the axial direction. However, since the crankshaft is coupled with the rotor as described above, the axial load is increased due to the self weight of the crankshaft and the self weight of the rotor, and the friction loss with the cylinder block can be increased by the axial load . In view of this, a bearing which is in point contact with a ball bearing such as a ball bearing is provided between the thrust surface of the cylinder block and the thrust surface of the crankshaft, thereby reducing the axial friction loss.

1 to 5, a bearing hole 212 constituting a journal bearing surface 215 is formed at the center of the cylinder block 210 so that the crank shaft 220 is inserted and radially supported. And a thrust surface 213 is formed around the upper end of the bearing hole 212 so that a ball bearing assembly 300 for supporting the crank shaft 220 in an axial direction is placed . A bearing restraining portion 214 is formed at an edge of the thrust surface 213 at a predetermined height so that a lower washer (or a second washer) 332 to be described later can be radially supported. In this case, the thrust surface 227 of the crankshaft 220 opposed to the thrust surface 213 of the cylinder block 210 may be formed flat.

The bearing restraining portion 214 may have a height lower than an axial height of the ball bearing 300 so that the bearing restraining portion 214 may be positioned between the end surface of the bearing restraining portion 214 and the thrust surface 227 of the crankshaft 220. [ Is formed to be lower than the axial height of the ball bearing (300). The height of the bearing restricting portion 214 may be not greater than the thickness of the lower washer 332 to be described later.

4A, the bearing restricting portion 214 may be formed in an annular shape as shown in FIG. 4A, but may have a shape capable of restraining the lower washer 332 in the radial direction as shown in FIG. 4B, For example, at least three arc-shaped protrusions along the circumferential direction. Although not shown in the drawings, the bearing restricting portion may be formed to contact the inner circumferential surface of the lower washer.

In another embodiment, the bearing restraining portion may be formed on the thrust surface of the crankshaft, that is, on the thrust surface of the eccentric mass portion, although not shown in the drawings.

1 to 5, the ball bearing 300 includes an annular ball cage 310, at least three balls 320 rotatably coupled to the ball cage 310, And washers 331 and 332 installed to contact both sides of the balls 320 in the axial direction. The washer is not necessarily required, but may be provided on either side.

The diameter of the balls 320 is greater than the thickness of the ball cage 310. The balls 320 may be fixedly coupled to the ball cage 310.

The washers 331 and 332 may be divided into an upper washer 331 and a lower washer 332 with a ball 320 as a center, It is preferable that the lower washer 331 and the lower washer 332 are installed so as to be radially supported on the cylinder block 210 and the crank shaft 220, That is, the upper washer is inserted into the outer circumferential surface of the crankshaft together with the ball cage to be supported in the radial direction, while the lower washer 332 is supported by the bearing restraint (not shown) provided on the thrust surface 213 of the cylinder block 210 So that it can be brought into close contact with the inner circumferential surface of the portion 214 and restrained in the radial direction. The bearing restricting portion 214 may be formed around the throttling hole 212 in the thrust surface 213 of the cylinder block 210 so that the inner circumferential surface of the lower washer 332 is brought into contact with the outer circumferential surface thereof.

As described above, since the ball bearing 300 is installed between the cylinder block 210 and the crankshaft 220, the axial friction loss between the cylinder block 210 and the crankshaft 220 is significantly reduced The energy efficiency of the compressor can be improved. The lower washer 332 can be always maintained in its position as the ball bearing 300, particularly the lower washer 332, is constrained radially to the bearing restraining portion 214 of the cylinder block 210, 300) can be stably operated.

Other embodiments of the reciprocating compressor according to the present invention are as follows. That is, when the ball bearing is installed between the thrust surfaces as described above, due to the characteristics of the ball bearings, the oil leakage in the thrust direction is caused and the oil guided to the outside of the crankshaft from the middle of the crankshaft can no longer be picked up, , More precisely the oil can not be supplied to the sliding contact surface with the sleeve, or the upper end can not be worn. In addition, the length of the moment arm is increased by the height of the ball bearing, and the compressor efficiency may be reduced.

Accordingly, the ball bearing is inserted into the cylinder block or the crankshaft so that the interval between the crankshaft and the cylinder block is reduced so that the oil outlet hole of the crankshaft is covered with the journal bearing surface to minimize leakage of oil from the center of the crankshaft, The length of the arm can be reduced to improve the compressor efficiency.

For this purpose, as shown in FIGS. 6 and 7, a bearing insertion groove 228 may be formed to allow the ball bearing 300 to be inserted. The axial height d of the bearing insertion groove 228 is not higher than the axial height h of the ball bearing 300. For example, Is formed so as not to be lower than 1/2 of the axial height h of the ball bearing 300 so that the oil does not leak between the cylinder block 210 and the thrust surfaces 213 and 227 of the crankshaft 220 And may be desirable. In other words, the axial height (i.e., depth) d of the bearing insertion groove 228 is set such that the axial distance between the cylinder block 210 and the crankshaft 220 T) is not greater than the axial height (h) of the ball bearing (300).

The bearing insertion groove 228 may be formed in the thrust surface 213 of the cylinder block 210 and the thrust surface 213 of the cylinder block 210 and the crankshaft 220, As shown in FIG.

7, the ball bearing 300 is inserted into a bearing insertion groove 228 formed in the crankshaft 220, so that the distance t between the cylinder block 210 and the crankshaft 220 Is smaller than the height h of the ball bearing 300 so that the length of the moment arm is shortened so that the force F2 applied to the first journal bearing surface 229a and the second journal bearing surface 229b, (F3) is reduced, so that the friction loss at the journal bearing surfaces 229a and 229b can be reduced so that the energy efficiency of the compressor can be improved. For example, the distance from the center of the cam portion 223 to the center of the cam portion 223 from the first journal bearing surface 229a that supports the journal bearing surface, that is, the repulsive force against the gas force applied to the cam portion 223 L1 is shortened while the distance L2 from the first journal bearing surface 229a to the second journal bearing surface 229b acting as a force against the first journal bearing surface 229a becomes longer to form the first journal bearing surface 229a and the second journal bearing surface 229b, 2 forces F2 (F3) applied to the two journal bearing surfaces 229b can be reduced. In the figure, F1 is the gas force applied to the cam portion, and the gas force is determined by the internal pressure and cross-sectional area of the cylinder.

FIG. 8 is a view showing a state in which a ball bearing is installed between the cylinder block and the crankshaft, and the ball bearing is inserted into the crankshaft to reduce the distance from the cam portion to the first journal bearing surface by about 5 mm, This graph shows the change in force applied to each journal bearing surface when the gap to the journal bearing surface is increased by about 5 mm.

That is, when the ball bearing is simply installed on the opposite surface between the cylinder block and the crankshaft so as to have a predetermined height, as shown in Fig. 8 (a), the ball bearing acts on the cam portion corresponding to the gas force The force F1 is about 600N. In this case, the force F2 acting on the first journal bearing surface is about 1000N and the force F3 acting on the second journal bearing surface is about 300N. However, when the ball bearing is inserted into the cylinder block 210 or the crankshaft 220 as in the present invention, the force F1 acting on the cam portion as shown in FIG. 8 (b) The force F2 acting on the first journal bearing surface is about 850N and the force F3 acting on the second journal bearing surface is about 150N.

As described above, when the bearing insertion groove is formed in the thrust surface of the crankshaft and a part of the ball bearing is inserted into the bearing insertion groove, the force acting on the first journal bearing surface is reduced by about 20% The force acting on the second journal bearing surface is reduced by about 50%, so that the torque required for the motor as a whole is reduced, and the energy efficiency (EER) of the compressor is improved.

The oil inflow hole 226c is formed at a position at least partially covered with the journal bearing surface 215 of the cylinder block 210 so that the oil guided through the first oil groove 226b Leakage from the cylinder block 210 to the crankshaft 220 can be minimized and the lubricating performance in the cam portion can be improved to further improve the efficiency of the compression device.

For example, as shown in FIG. 9, the first oil groove 226b of the crankshaft 220 is formed in a spiral shape so as to have a predetermined inclination angle, and its winding angle is in the range of about 60 DEG to about 90 DEG . This is so that the oil inflow hole 226c is formed at a position that is less than the conventional normal winding angle. Although not shown in the drawings, the length of the first oil groove may be reduced while keeping the inclination angle of the first oil groove the same as in the prior art, so that at least a part of the oil outlet hole may be formed so as to be covered by the upper half of the journal bearing surface.

The first oil groove 226b may be formed at one inclination angle, but may be formed at a plurality of inclination angles. This is to allow a large amount of oil to be stored in the concentrated region where the load is concentrated on the journal bearing surface, that is, the first journal bearing surface 229a close to the cam portion 223.

For example, when the first oil groove 226b is formed at a plurality of inclined angles, as shown in FIG. 9, the first oil groove 226a is inclined at an inclination angle? 1 of, for example, The upper groove g2 may be formed at an inclination angle? 2 of, for example, 30 ° from the oil groove 226c to the oil groove 226c at a predetermined height or more.

A portion of the oil that rides on the first oil groove 226b is discharged to the upper end of the first oil groove 226b, The edges between the bearing surface and the thrust surface may be cut to form a chamfer or rounded oil pocket 216. 10, the lowermost point of the oil inflow hole 226c may be formed at least at a predetermined height (for example, a height of the oil pocket 216) rather than the lowermost point of the oil pocket 216 so that at least a part of the oil inflow hole 226c is covered by the journal bearing surface of the cylinder block. The longest distance L3 from the bottom surface of the eccentric mass portion 222 of the crankshaft 220 is smaller than the longest distance L3 between the cylinder block 210 and the cylinder block 210, Is not shorter than the shortest distance (L4) to the journal bearing surface (215) of the cylinder block (210) and the crankshaft (220).

As described above, since the oil inflow hole 226c is formed so as to be at least partially obscured by the journal bearing surface 215 of the cylinder block 210, the ball bearing 300 through which the oil can be discharged is installed on the thrust surface The amount of oil that is guided through the first oil groove 226b may be reduced to lean between the cylinder block 210 and the crankshaft 220. The oil guided through the first oil groove 226b is guided to the second oil passage 225b through the oil inflow hole 226c so that the gap between the cam portion 223 and the connecting rod 230 The lubricating oil can be smoothly taken up to the upper end of the crankshaft 220 to effectively cool the transmission portion 200, thereby further improving the efficiency of the compressor.

Meanwhile, another embodiment of the structure for supporting the ball bearing of the reciprocating compressor according to the present invention is as follows.

That is, in the above-described embodiment, the ball bearings 300 are inserted into the bearing insertion grooves 228 provided on the bottom surface of the eccentric mass portion 222 of the crankshaft. However, The thrust surface of the crankshaft and the thrust surface of the cylinder block, respectively.

11 and 12, a thrust surface 213 of the cylinder block 210 and a thrust surface 217 of a crankshaft 220 opposed to the thrust surface 213 of the cylinder block 210 are formed with a part of the ball 320 of the ball bearing 300 The bearing insertion grooves 217 and 228 are formed. The bearing insertion recesses 217 and 228 are formed in an annular shape so that the balls 320 of the ball bearing 300 are slidable in the circumferential direction and the depth of the bearing insertion recesses 217 and 228 is smaller than that of the ball cage 310 The diameter of the balls 320 is preferably at most 50% of the diameter of the balls 320. [

The ball bearings 300 may be formed to have the same curvature as that of the balls 320 so that the outer circumferential surfaces of the balls 320 are linearly in contact with the radial direction.

Here, washers 331 and 332 having an arc-shaped cross-sectional shape as shown in FIG. 13 may be installed on the inner circumferential surface of the bearing insertion grooves 217 and 228. The washers 331 and 332 are preferably made of a material having better wear resistance than the cylinder block 210 or the crankshaft 220.

As shown in FIG. 14, the bearing insertion grooves 217 and 228 are formed in a rectangular shape as in the above-described embodiment. The bearing insertion grooves 217 and 228 have a rectangular outer peripheral surface and an inner peripheral surface, The washer 331 and the washer 332 having an arc-shaped sectional shape such as a curvature may be inserted and installed, respectively. In this case, the washer can be easily assembled. 15, the bearing insertion grooves 217 and 228 are formed in a rectangular shape as in the above-described embodiment, and annular plate washers 331 and 332 are inserted into the bearing insertion grooves 217 and 228, respectively. May be inserted and installed. In this case, the washer can be easily manufactured.

When the bearing insertion grooves 217 and 228 are respectively formed between the cylinder block 210 and the crankshaft 20 so that a part of the ball 320 of the ball bearing 300 is inserted, The height of the ball bearings 300 is lowered to a certain extent so that the amount of oil leaked to the cylinder block 210 and the crankshaft 20 can be reduced and the friction loss due to the gas force can be reduced. Energy efficiency can be improved.

On the other hand, when the reciprocating compressor according to the present invention is applied to a refrigerating machine, the performance of the refrigerating machine can be improved.

For example, as shown in FIG. 16, in a refrigerating machine 700 having a refrigerant compression refrigeration cycle including a compressor, a condenser, an expander and an evaporator, a main board 710 Is provided with a reciprocating compressor (C) in which a bearing, which is in point contact with a thrust surface, such as a ball bearing, is inserted into a bearing insertion groove provided in the thrust surface. The reciprocating compressor (C) is formed at a position where an oil hole communicating the oil groove of the crankshaft and the oil passage is obscured on the journal bearing surface. As a result, the refrigerating machine can obtain the effect described above in the reciprocating compressor, and the performance of the refrigerating machine to which the reciprocating compressor is applied can be improved.

The reciprocating compressor according to the present invention and the refrigeration apparatus using the same have been described in the context of a single reciprocating compressor having one cylinder, but in some cases, the reciprocating compressor having a plurality of cylinders and the refrigeration apparatus using the same can be applied.

1 is a longitudinal sectional view showing an example of a reciprocating compressor of the present invention,

Fig. 2 is a front view showing the crankshaft according to Fig. 1,

3 is a perspective view showing the cylinder block according to FIG. 1,

Fig. 4 is a perspective view showing the bearing restraining portion of the cylinder block according to Fig. 3, wherein Fig. 4 (a) is an annular shape, Fig. 4 (b)

5 is a longitudinal sectional view showing a state where a ball bearing is installed between the cylinder block and the crankshaft shown in FIG.

FIG. 6 is a perspective view of the cylinder block, the crankshaft and the ball bearing according to FIG. 1,

FIG. 7 is a vertical sectional view of the cylinder block, the crankshaft and the ball bearing shown in FIG. 1,

FIG. 8 is a cross-sectional view of a reciprocating compressor according to the present invention. FIG. 8 is a cross-sectional view of the reciprocating compressor shown in FIG. A graph showing the change of the force,

Figure 9 is a schematic view of a first oil groove deployed in the crankshaft according to Figure 1,

Fig. 10 is a schematic view for explaining the position of the oil outlet hole according to Fig. 1,

Fig. 11 is a longitudinal sectional view showing a thrust surface of a crankshaft and a cylinder block to which another embodiment of the support structure of the ball bearing according to Fig. 1 is applied; Fig.

12 is a sectional view taken along the line "II-II" in Fig. 11,

FIGS. 13 to 15 are longitudinal sectional views showing other embodiments of the support structure of the ball bearing according to FIG.

16 is a schematic view showing an example of a refrigerator to which the reciprocating compressor of the present invention is applied.

DESCRIPTION OF REFERENCE NUMERALS

1: sealed container 100:

200: compression section 210: cylinder block

212: bearing hole 213: thrust face (cylinder block)

214: Bearing restricting portion 215: Cylinder block journal bearing surface

216: Oil pocket 217: Bearing insertion groove (cylinder block)

220: crank shaft 221: shaft portion

222: eccentric mass portion 223: cam portion

225a: first oil passage 225b: second oil passage

226a: first oil outlet hole 226b: first oil groove

226c: Oil inflow hole 226d: Third oil inflow hole

226e: second oil groove 227: thrust face (crankshaft)

228: bearing insertion grooves 229a, 229b: crankshaft journal bearing surface

300: bearing assembly (ball bearing) 310: ball cage

320: ball 331,332: washer

Claims (21)

A cylinder block in which a bearing hole is formed so as to form a journal bearing surface; A crankshaft formed with a plate-like extension portion wider than the bearing hole of the cylinder block and inserted in the bearing hole of the cylinder block and supported in the radial direction; And And a bearing assembly installed between the thrust surface around the bearing hole of the cylinder block and the thrust surface of the crankshaft facing thereto, and axially supporting the crankshaft with respect to the cylinder block, The bearing restraining portion is formed on at least one of the thrust surfaces of the cylinder block and the crankshaft so as to confine at least a part of the bearing assembly in the radial direction, Wherein an axial gap between a thrust surface of the crankshaft or a thrust surface of the cylinder block and the corresponding bearing restraining portion is formed to be smaller than or equal to an axial height of the bearing assembly. The method according to claim 1, Wherein the bearing restraining portion is formed of at least three protrusions along an annular projection or a circumferential direction so that the outer circumferential surface or the inner circumferential surface of the bearing assembly abuts. delete The method according to claim 1, Wherein a thrust surface of the cylinder block on which the bearing restraining portion is not formed is flattened from a thrust surface of the cylinder block or a thrust surface of the crankshaft facing the thrust surface of the cylinder block. The method according to claim 1, Wherein a bearing insertion groove is formed in a thrust surface of the cylinder block, or a thrust surface of the crankshaft facing the thrust surface of the cylinder block, on a side of the thrust surface on which the bearing restraining portion is not formed, so that at least a part of the bearing assembly is inserted. 6. The method of claim 5, Wherein the axial height of the bearing insertion groove is formed such that a minimum axial spacing between a thrust surface of the cylinder block and a thrust surface of the crankshaft is less than or equal to an axial height of the bearing assembly. delete 6. The method of claim 5, The bearing assembly includes a ball cage formed in an annular shape having a predetermined thickness, at least three balls formed in a diameter larger than the thickness of the ball cage and coupled to the ball cage, And at least one washer provided on at least one of both sides in the axial direction of the balls, Wherein the washer comprises a first washer and a second washer respectively installed on both sides in the axial direction of the balls, the first washer is inserted into the bearing insertion groove, and the second washer is provided on the outer side of the bearing insertion groove Installed reciprocating compressor. delete delete delete delete delete The method according to claim 1, At least one oil passage is formed in the crankshaft, at least one oil groove is formed on the outer circumferential surface of the crankshaft, and the oil passage and the oil groove are connected to each other through at least one oil outlet hole and the oil inlet hole Respectively, Wherein an oil inflow hole is formed in an oil groove communicating with a thrust surface of the cylinder block and a thrust surface of the crankshaft in the oil groove and at least a part of the oil inflow hole is formed to be covered with a journal bearing surface of the cylinder block, compressor. delete 15. The method of claim 14, Wherein the oil groove is formed to have a plurality of inclination angles and an inclination angle of a portion adjacent to the oil inlet hole among the plurality of inclination angles is formed to be smaller than an inclination angle of a portion far from the oil inlet hole. 15. The method of claim 14, Wherein a corner between the journal bearing surface and the thrust surface of the cylinder block is chamfered or rounded. A crankshaft for transmitting a rotational force is supported in the cylinder block in a radial direction and an axial direction and a connecting rod is coupled to the crankshaft to convert the rotational motion into a linear motion and a piston coupled to the connecting rod reciprocates in the cylinder, In the reciprocating compressor, At least one oil passage is formed in the crankshaft, at least one oil groove is formed on the outer circumferential surface of the crankshaft, and the oil passage and the oil groove are connected to each other through at least one oil outlet hole and the oil inlet hole Respectively, Wherein an oil inflow hole is formed in an oil groove communicating with the thrust surface of the cylinder block and the thrust surface of the crankshaft among the oil grooves and at least a portion of the oil inflow hole is formed to be covered with the journal bearing surface of the cylinder block, Wherein the oil groove is formed to have at least one inclination angle. delete 19. The method of claim 18, Wherein the oil groove is formed to have a plurality of inclination angles and an inclination angle of a portion adjacent to the oil inlet hole among the plurality of inclination angles is formed to be smaller than an inclination angle of a portion far from the oil inlet hole. compressor; A condenser connected to a discharge side of the compressor; An expander connected to the condenser; And And an evaporator connected to the inflator and connected to the suction side of the compressor, Wherein the compressor comprises the compressor according to any one of claims 1, 2, 4, 6, 8, 14, 16 to 18, and 20.

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