CN114370385A

CN114370385A - Reciprocating compressor

Info

Publication number: CN114370385A
Application number: CN202011374084.7A
Authority: CN
Inventors: 孙映夫; 朴馥安; 朴仁范; 金敬晧
Original assignee: LG Electronics Inc
Current assignee: LG Electronics Inc
Priority date: 2020-10-15
Filing date: 2020-11-30
Publication date: 2022-04-19
Anticipated expiration: 2040-11-30
Also published as: DE102021108327A1; CN114370385B; KR102344890B1

Abstract

Disclosed is a reciprocating compressor capable of minimizing an unbalance force generated during the movement of a rotary shaft and a piston, wherein the reciprocating compressor comprises: a piston; a rotating shaft; and a balancer coupled to the rotating shaft in a penetrating manner and rotating together with the rotating shaft, the balancer including: a coupling portion formed by extending and expanding from a coupling hole in contact with an outer circumferential surface of a rotary shaft toward a radial outer side of the rotary shaft; and an eccentric mass part coupled to one side of the coupling part, and one surface of the eccentric mass part, which is opposite to the housing in a height direction of the rotation shaft, is inclined toward a direction opposite to the housing.

Description

Reciprocating compressor

Technical Field

The present invention relates to a reciprocating compressor, and more particularly, to a reciprocating compressor capable of minimizing an unbalanced force generated during the movement of a rotary shaft and a piston.

Background

The compressor is a device that discharges a high-pressure fluid by compressing the fluid, or operates a machine using energy generated when the high-pressure fluid is discharged.

A reciprocating compressor, which is a type of compressor, compresses a refrigerant by reciprocating a piston in a cylinder tube, and then discharges the refrigerant to a discharge space in a high pressure state.

Specifically, the rotational motion of the rotary shaft is transmitted to a piston connected to the rotary shaft, and the refrigerant is compressed by the reciprocating motion of the piston and then discharged to the discharge space in a high-pressure state.

At this time, an unbalanced force is generated in the compressor due to the eccentric rotation of the rotary shaft and the reciprocation of the piston. This may induce vibration of the rotary shaft and the piston, and may increase noise generated during driving of the reciprocating compressor.

Therefore, in order to reduce such unbalanced force, an additional balancer may be provided at the rotation shaft.

Here, the balancer refers to a balancing device attached to the outer circumference of the rotating body to balance the rotating body.

In the conventional reciprocating compressor, one surface of the balancer facing the housing is formed as a plane parallel to the radial direction of the rotary shaft.

However, in the conventional reciprocating compressor, there is a minimum interval between the housing and the balancer. That is, the design of the reciprocating compressor may be limited. Therefore, the balancer cannot sufficiently balance the rotating body.

Korean laid-open patent publication No. 10-2004-. Specifically disclosed is a hermetic reciprocating compressor including a weight balance member located at a boundary portion of a main shaft portion and a crank portion of a crankshaft member.

However, in this type of reciprocating compressor, the weight balancing member is formed in a rectangular parallelepiped shape. Therefore, there is a minimum value of the interval between the housing and the weight balancing member, so that the design of the reciprocating compressor may be limited.

Korean authorized utility model publication No. 20-0126118 discloses a reciprocating type compressor. Specifically, disclosed is a reciprocating compressor provided with an eccentric portion provided to a rotary shaft so as to be eccentric to the rotary shaft, and a weight balancer that cancels out imbalance of force generated by eccentric rotation of the eccentric portion.

However, in this type of reciprocating compressor, the weight balancer is also formed in a rectangular parallelepiped shape. Thus, the design of the reciprocating compressor may be limited.

Documents of the prior art

Patent document

Korean laid-open patent publication No. 10-2004-0009500 (2004.01.31)

Korean granted Utility model publication No. 20-0126118 (1998.07.03)

Disclosure of Invention

An object of the present invention is to provide a reciprocating compressor capable of minimizing an unbalanced force generated during the movement of a rotary shaft and a piston.

Another object of the present invention is to provide a reciprocating compressor capable of further reducing a space between a housing and a balancer and further increasing a balancing effect of the balancer.

Another object of the present invention is to provide a reciprocating compressor in which an interval between one end of a balancer and a housing and an interval between the other end of the balancer and the housing are manufactured at an interval ratio most suitable for a preset driving condition.

In order to achieve the object, a reciprocating compressor according to an embodiment of the present invention includes: a piston; a rotating shaft coupled to the piston so as to be rotatable relative to the piston; a balancer that is coupled to the rotating shaft and rotates together with the rotating shaft; and a housing accommodating the piston, the rotation shaft, and the balancer in an interior thereof, the rotation shaft including: a support part extending in one direction; and an eccentric portion formed to extend in the one direction from one end of the support portion, and a center axis of the eccentric portion and a center axis of the support portion are not arranged on a straight line, the balancer including: a coupling portion formed by extending and expanding from a coupling hole contacting an outer circumferential surface of the eccentric portion toward a radial outer side of the eccentric portion; and an eccentric mass portion coupled to one side of the coupling portion, extending toward a radially inner side of the support portion, and one surface of the eccentric mass portion opposite to the housing in a height direction of the rotation shaft is inclined toward a direction opposite to the housing.

In addition, the one surface of the eccentric mass portion may be formed as a curved surface.

In addition, at least a portion of the one surface of the eccentric mass portion may be formed in a shape corresponding to an inner circumferential surface of the housing.

In addition, the one surface of the eccentric mass portion may be formed as a plane.

In addition, an uppermost end of the one surface of the eccentric mass portion in the height direction of the rotating shaft may be spaced apart from the inner circumferential surface of the housing by a first interval in the height direction of the rotating shaft, a lowermost end of the one surface of the eccentric mass portion in the height direction of the rotating shaft may be spaced apart from the inner circumferential surface of the housing by a second interval in the height direction of the rotating shaft, and a value obtained by dividing the first interval by the second interval may be a predetermined prescribed interval ratio.

The predetermined interval ratio may be 0.9 or more and 1.1 or less.

In addition, a reciprocating compressor of another embodiment of the present invention includes: a piston; a rotating shaft extending in one direction and coupled to the piston so as to be rotatable relative to the piston; a balancer coupled to an outer circumference of the rotating shaft and rotating together with the rotating shaft; and a housing accommodating the piston, the rotation shaft, and the balancer in an interior thereof, the rotation shaft including: a support portion extending in the one direction; and an eccentric portion formed to extend in the one direction from one end of the support portion, and a center axis of the eccentric portion and a center axis of the support portion are not arranged on a straight line, the balancer including: a coupling portion formed by extending and expanding from a coupling hole contacting an outer circumferential surface of the eccentric portion toward a radial outer side of the eccentric portion; and an eccentric mass portion coupled to one side of the coupling portion and extending radially inward of the support portion, wherein one surface of the eccentric mass portion facing the housing in a height direction of the rotating shaft is bent at a predetermined angle in a direction opposite to the housing.

In addition, in the one surface of the eccentric mass portion, a portion located radially outside the eccentric portion may be formed as a curved surface with reference to a bending line.

In addition, the portion of the eccentric mass portion may be formed in a shape corresponding to an inner circumferential surface of the housing.

In addition, in the one surface of the eccentric mass portion, a portion located radially outside the eccentric portion may be formed as a flat surface with reference to a bending line.

In addition, an uppermost end of the one surface of the eccentric mass portion in the height direction of the rotating shaft and the inner circumferential surface of the housing may be spaced apart by a first interval in the height direction of the rotating shaft, a lowermost end of the one surface of the eccentric mass portion in the height direction of the rotating shaft and the inner circumferential surface of the housing may be spaced apart by a second interval in the height direction of the rotating shaft, and a value obtained by dividing the first interval by the second interval may be a predetermined interval ratio.

The predetermined interval ratio may be 0.9 or more and 1.1 or less.

In addition, a reciprocating compressor according to another embodiment of the present invention includes: a piston formed in a cylindrical shape; a rotating shaft coupled to the piston so as to be rotatable relative to the piston; a balancer that is coupled to the rotating shaft and rotates together with the rotating shaft; and a housing accommodating the piston, the rotation shaft, and the balancer therein, a projection being formed at a portion of the housing, the rotation shaft including: a support part extending in one direction; and an eccentric portion formed to extend in the one direction from one end of the support portion, and a center axis of the eccentric portion and a center axis of the support portion are not arranged on a straight line, the balancer including: a coupling portion formed by extending and expanding from a coupling hole contacting an outer circumferential surface of the eccentric portion toward a radial outer side of the eccentric portion; and an eccentric mass portion coupled to one side of the coupling portion and extending toward a radially inner side of the support portion, the protrusion and the eccentric mass portion being overlapped in a height direction of the rotating shaft, the protrusion protruding in a direction opposite to the eccentric mass portion, the protrusion being formed in a shape corresponding to the eccentric mass portion.

In addition, the rotating shaft may include a balance portion disposed between the support portion and the eccentric portion and formed to be expanded from the one end of the support portion toward a radially outer side of the support portion.

Further, a connecting rod may be included, which extends in a direction different from the one direction, and one end of the connecting rod may be coupled to the piston, and the other end thereof may be coupled to the eccentric portion in a relatively rotatable manner.

Among the various effects of the present invention, the effects that can be obtained by the above-described solution are as follows.

First, one surface of the balancer opposite to the housing is inclined toward the opposite direction to the housing.

That is, one surface of the balancer opposite to the housing is formed in a shape corresponding to the inner circumferential surface of the housing.

Therefore, the balance force generated by the balancer can be sufficiently secured during the driving of the compressor, and the driving force generated during the movement of the rotary shaft and the piston and the balance force generated by the balancer can be compensated for each other, so that the total unbalance force can be minimized.

This can further reduce the vibration of the rotary shaft and the piston.

Further, it is possible to minimize noise generated by vibration of the rotary shaft and the piston.

In addition, by inclining one surface of the balancer opposite to the housing toward the opposite direction to the housing, the interval between the balancer and the housing can be further reduced.

That is, the space between the balancer and the housing can be further reduced.

Therefore, the balancing effect by the balancer can be further increased.

In addition, it is possible to adjust the interval between one end of the balancer and the housing and adjust the interval between the other end of the balancer and the housing according to preset driving conditions.

Therefore, the interval between one end of the balancer and the housing and the interval between the other end of the balancer and the housing can be manufactured at an interval ratio most suitable for the preset driving conditions.

Drawings

Fig. 1 is a sectional view showing a reciprocating compressor according to an embodiment of the present invention.

Fig. 2 is an enlarged sectional view illustrating the reciprocating compressor of fig. 1.

Fig. 3 is an enlarged sectional view showing a balancer according to an embodiment of the present invention.

Fig. 4 is an enlarged sectional view showing a balancer according to another embodiment of the present invention.

Fig. 5 is a side view showing the rotary shaft and the piston of fig. 1.

Fig. 6 is a plan view showing the rotary shaft and the piston of fig. 1.

Fig. 7 is a perspective view illustrating the balancer of fig. 1.

Fig. 8 is a plan view illustrating the balancer of fig. 1.

Fig. 9 is a sectional view illustrating the balancer of fig. 1.

Fig. 10 is a sectional view illustrating the balancer of fig. 3.

Fig. 11 is a sectional view illustrating the balancer of fig. 4.

Fig. 12 is a graph illustrating unbalanced forces generated during the movement of the rotary shaft and the piston according to an embodiment of the present invention.

Description of the reference numerals

1: the reciprocating compressor 10: shell body

110: upper case 111: projecting part

120: lower shell 11: refrigerant suction pipe

12: refrigerant discharge pipe 20: oil supply device

21: oil 30: compression part

31: the cylinder module 311: cylinder barrel

312: cylinder inner space 313: bearing assembly

314: plate portion 32: piston

321: piston pin 322: connecting rod

40: driving motor 41: stator

42: rotor 50: rotating shaft

51: support portion 52: eccentric part

53: the balance section 54: oil supply passage

60: balancer 61: joining part

611: the coupling hole 62: eccentric mass part

S1: compression space S2: suction space

S3: discharge space S4: oil storage space

g 1: first interval g 2: second interval

Detailed Description

Hereinafter, the reciprocating compressor 1 according to the embodiment of the present invention will be described in more detail with reference to the accompanying drawings.

In the following description, some descriptions of the constituent elements may be omitted to clarify the features of the present invention.

In the present specification, the same components are given the same reference numerals and the repetitive description thereof will be omitted even in the embodiments different from each other.

The drawings are only for convenience of understanding the embodiments disclosed in the specification and do not limit the technical ideas disclosed in the specification.

Unless the context clearly dictates otherwise, expressions in the singular include expressions in the plural.

Hereinafter, a reciprocating compressor 1 according to an embodiment of the present invention will be described with reference to fig. 1 to 4.

The reciprocating compressor 1 of the present invention includes a casing 10, a refrigerant suction pipe 11, a refrigerant discharge pipe 12, an oil supply device 20, a driving motor 40, a compression part 30, and a rotary shaft 50.

The housing 10 forms an external appearance of the reciprocating compressor 1.

A space for accommodating the oil supply device 20, the compression part 30, the driving motor 40, and the rotation shaft 50 is formed inside the housing 10. That is, the oil supply device 20, the compression part 30, the drive motor 40, and the rotary shaft 50 are accommodated inside the casing 10.

The housing 10 may include an upper case 110 and a lower case 120.

In the illustrated embodiment, the upper and

lower cases

110 and 120 are formed in a dome (dome) shape. Specifically, the upper case 110 is formed in a dome shape that is raised toward the upper side, and the lower case 120 is formed in a dome shape that is depressed toward the lower side.

A protrusion 111 may be formed at a portion of the upper case 110. This will be described later in detail (refer to fig. 4).

The lower end of the upper case 110 is combined with the upper end of the lower case 120. In one embodiment, the upper case 110 and the lower case 120 are combined by welding.

The combined upper case 110 and lower case 120 form an inner space of the case 10. At this time, the internal space is sealed.

The internal space of the casing 10 includes a compression space S1, a suction space S2, a discharge space S3, and an oil storage space S4.

The compression space S1 is a space where the refrigerant is compressed into a high-pressure state by the piston 32.

The compression space S1 is formed between one end of the piston 32 and the inner periphery of the cylinder 311.

The suction space S2 is a space through which the refrigerant flowing from the refrigerant suction pipe 11 passes before flowing into the compression space S1.

The suction space S2 is combined with the opened side of the refrigerant suction pipe 11. Therefore, the refrigerant discharged from the one side of the refrigerant suction pipe 11 flows into the suction space S2.

The discharge space S3 is a space through which the refrigerant discharged from the compression space S1 in a high-pressure state passes before being discharged from the refrigerant discharge tube 12.

The discharge space S3 is connected to the open side of the refrigerant discharge pipe 12. Therefore, the refrigerant existing in the discharge space S3 can be discharged to the outside of the casing 10 through the one side of the refrigerant discharge pipe 12.

In short, the refrigerant flowing into the casing 10 through the refrigerant suction pipe 11 passes through the suction space S2, the compression space S1, and the discharge space S3 in this order, and is then discharged to the outside of the casing 10 through the refrigerant discharge pipe 12.

The oil storage space S4 is a space for storing the oil 21, and the oil 21 assists the compression part 30 and the rotation shaft 50 to move smoothly.

The oil storage space S4 is formed in the lower portion of the internal space of the casing 10.

The oil 21 in the oil storage space S4 is collected in the oil storage space S4 by gravity.

The oil storage space S4 will be described in more detail later together with the description of the oil supply device 20.

The refrigerant suction pipe 11 and the refrigerant discharge pipe 12 penetrate the upper shell 110 or the lower shell 120. In the illustrated embodiment, the refrigerant suction pipe 11 and the refrigerant discharge pipe 12 are penetratingly coupled to the lower casing 120.

One side of the refrigerant suction pipe 11 is connected to the case 10. The other side of the refrigerant suction pipe 11 is disposed outside the reciprocating compressor 1, and a refrigerant suction port is formed.

In an embodiment, a suction valve (not shown) may be provided at the refrigerant suction pipe 11.

The suction valve adjusts the inflow amount of the refrigerant flowing into the refrigerant suction pipe 11.

When the refrigerant flows into the suction space S2, the suction valve is opened, and when the refrigerant is discharged from the discharge space S3 to the outside, the suction valve is closed. That is, when the compression space S1 increases, the suction valve is opened, and when the compression space S1 decreases, the suction valve is closed.

One side of the refrigerant discharge pipe 12 is connected to the casing 10 and is spaced apart from the refrigerant suction pipe 11. The other side of the refrigerant discharge pipe 12 is disposed outside the reciprocating compressor 1, and a refrigerant discharge port is formed.

In one embodiment, a discharge valve (not shown) may be provided in the refrigerant discharge pipe 12.

The discharge valve adjusts the discharge amount of the refrigerant discharged from the refrigerant discharge pipe 12.

When the refrigerant is discharged from the discharge space S3 to the outside, the discharge valve is opened, and when the refrigerant flows into the suction space S2, the discharge valve is closed. That is, when the compression space S1 decreases, the discharge valve opens, and when the compression space S1 increases, the discharge valve closes.

On the other hand, the oil 21 is also supplied to the reciprocating compressor 1 in addition to the refrigerant. Specifically, the components are smoothly moved by supplying the oil 21 between the components moving inside the reciprocating compressor 1.

For this purpose, an oil storage space S4 for supplying the oil 21 is provided in a lower space of the internal space of the casing 10.

The oil 21 in the oil storage space S4 is supplied to each component of the reciprocating compressor 1 by the oil supply device 20.

The oil supply device 20 sucks the oil 21 stored in the oil storage space S4 to move the oil 21 into the rotary shaft 50, which will be described later.

The oil supply device 20 is coupled to a lower side of the rotary shaft 50. At this time, the oil supply device 20 communicates with the oil supply passage 54 inside the rotary shaft 50. This will be described in detail later together with the description of the rotation shaft 50.

The lower end of the oil supply device 20 is disposed in the oil storage space S4. Specifically, the lower end portion of the oil supply device 20 extends downward so as to be immersed in the oil 21 in the oil storage space S4.

Therefore, the oil supply device 20 can supply the oil 21 from the oil storage space S4 to the compression section 30 and the rotation section.

In the illustrated embodiment, the oil supply device 20 is formed in a cylindrical shape extending toward the same direction as the extending direction of the rotation shaft 50.

However, the oil supply device 20 is not limited to the illustrated form, and may be formed in various forms. In an embodiment, the oil supply device 20 may be formed in the form of a centrifugal pump. In another embodiment, the oil supply device 20 may be formed in the form of a viscous pump.

The oil 21 sucked by the oil supply device 20 is supplied to the compression part 30 and the rotation shaft 50. After that, the oil 21 sucked into the compression section 30 and the rotary shaft 50 falls down to the oil storage space S4 by the action of gravity.

As a result, the oil 21 of the oil storage space S4 repeats the following process: the oil is supplied to the compression unit 30 and the rotary shaft 50 by the oil supply device 20, and then recovered to the oil storage space S4, so that the oil 21 circulates inside the reciprocating compressor.

At this time, the compression portion 30 is composed of a cylinder block 31 and a piston 32.

The compression unit 30 compresses the refrigerant in the compression space S1 and discharges the compressed refrigerant to the discharge space S3.

The cylinder block 31 includes a cylinder 311, a cylinder inner space 312, a bearing 313, and a plate portion 314.

The cylinder 311 is formed in a cylindrical shape.

In the illustrated embodiment, the cylinder 311 is formed in a cylindrical shape extending in the lateral direction.

However, the cylinder 311 is not limited to the illustrated form, and may be formed in various forms. For example, the cylinder 311 may be formed as a V-shaped cylinder 311.

A hollow is formed inside the cylinder 311. Hereinafter, the hollow space is referred to as a "cylinder inner space 312".

The cylinder inner space 312 accommodates a piston 32 described later.

The inner wall of the cylinder inner space 312 is ground. Therefore, the reciprocating motion of the piston 32 inserted into the cylinder inner space 312 can be made smoother.

The bearing 313 supports a rotational movement of the rotary shaft 50 described later.

The bearing 313 is combined with the outer circumference of the rotating shaft 50. Specifically, the bearing 313 is coupled to the outer circumference of the support portion 51 of the rotating shaft 50.

The bearing 313 is formed to surround the rotation shaft 50.

Plate portion 314 is coupled to one side of bearing 313.

The plate portion 314 is formed as a part of the outer periphery of the cylinder 311.

In the illustrated embodiment, the plate portion 314 is formed in a plate shape extending from one side of the bearing 313 toward the lateral direction.

However, the plate portion 314 is not limited to the illustrated form, and may be formed in various forms.

A piston 32 is inserted into the cylinder block 31. Specifically, the piston 32 is inserted into the cylinder tube inner space 312.

The piston 32 reciprocates in the cylinder bore inner space 312 and compresses the refrigerant in the compression space S1. Specifically, the piston 32 reciprocates in a state of being in close contact with the inner wall of the cylinder internal space 312.

The reciprocating compressor 1 is classified into a vertical compressor or a horizontal compressor according to the reciprocating direction of the piston 32.

In the illustrated embodiment, the piston 32 reciprocates in the lateral direction. Therefore, the reciprocating compressor 1 corresponds to a horizontal type compressor.

However, the piston 32 is not limited to the illustrated reciprocating direction, and may reciprocate in a variety of directions.

In addition, in the illustrated embodiment, the piston 32 is formed in a cylindrical shape.

However, the piston 32 is not limited to the illustrated form, and may be formed in various forms. For example, the piston 32 may be formed in a disk shape.

An end of the piston 32 opposite to the rotary shaft 50 and one surface of the cylinder 311 are in an opposing relationship to each other.

When the one end of the piston 32 and the one surface of the cylinder 311 are closest, a gap is formed between the one end of the piston 32 and the one surface of the cylinder 311.

That is, when the volume of the compression space S1 is minimized, the one end of the piston 32 and the one surface of the cylinder 311 are spaced apart from each other.

Further, a gap is also formed between the outer periphery of the piston 32 and the inner periphery of the cylinder 311.

Therefore, the one end of the piston 32 and the one surface of the cylinder 311 can be prevented from colliding with each other. This also prevents damage to the piston 32 and the cylinder 311.

However, if the gap is excessively increased, the refrigerant compression efficiency may be lowered.

Specifically, if the clearance is excessively increased, the temperature of the cylinder tube 311 and the discharged refrigerant may be increased. This may cause deterioration and carbonization of the oil 21, and may increase the amount of residue of the oil 21 adhering to the cylinder tube 311 and the piston 32. As a result, volumetric efficiency of the cylinder tube 311 may be reduced, and performance of the reciprocating compressor 1 may be reduced.

Therefore, the smaller the gap, the more advantageous in terms of the performance of the reciprocating compressor 1. Thereby, the gap should be appropriately adjusted according to the preset driving condition of the reciprocating compressor 1.

In one embodiment, an inner liner (liner) (not shown) of the cylinder 311 may be provided between the outer periphery of the piston 32 and the inner periphery of the cylinder 311.

The inner liner of the cylinder 311 prevents the outer periphery of the piston 32 and the inner wall of the cylinder 311 from being worn.

The inner periphery of the inner tube of the cylinder tube 311 is formed in a shape corresponding to the outer periphery of the piston 32. The outer periphery of the inner tube of the cylinder tube 311 is formed in a shape corresponding to the inner wall of the cylinder tube 311.

In one embodiment, the inner container of the cylinder 311 may be formed to have a hollow cylindrical shape formed therein.

The inner bladder of the cylinder 311 reduces the contact surface between the piston 32 and the cylinder 311, and guides the reciprocation of the piston 32.

Therefore, damage to the piston 32 and the cylinder 311 caused by friction between the piston 32 and the cylinder 311 can be prevented.

In addition, when the inner liner of the cylinder 311 is worn, the inner liner of the cylinder 311 is replaced only to repair the cylinder, and the piston 32 and the cylinder 311 do not need to be replaced.

When the piston 32 moves toward the rotary shaft 50, the volume of the compression space S1 formed by the piston 32 and the cylinder tube 311 increases and the pressure decreases. Therefore, the refrigerant flows into the compression space S1 through the refrigerant suction pipe 11 and the suction space S2 in this order.

In contrast, when the piston 32 moves in the direction opposite to the rotational shaft 50, the volume of the compression space S1 decreases and the pressure increases. Therefore, the pressure of the refrigerant in the compression space S1 increases, and the refrigerant passes through the discharge space S3 and the refrigerant discharge pipe 12 in this order and is discharged to the outside of the reciprocating compressor 1.

In the illustrated embodiment, as the piston 32 moves toward the right, the volume of the compression space S1 increases and the pressure decreases. In contrast, when the piston 32 moves toward the left side, the volume of the compression space S1 decreases and the pressure increases.

On the other hand, the piston 32 includes a piston pin 321 and a connecting rod 322.

The piston pin 321 is a means for connecting the piston 32 and the connecting rod 322.

The piston pin 321 is provided inside the piston 32.

The piston pin 321 is formed in a cylindrical shape.

In one embodiment, a hollow is formed inside the piston pin 321. Therefore, the weight of the piston 32 can be further reduced. Further, the weight of the reciprocating compressor 1 can be further reduced.

Oil 21 is supplied to the piston pin 321. Therefore, during the reciprocating motion of the piston 32, the piston pin 321 can be smoothly moved.

The piston pin 321 is combined with the connecting rod 322. Specifically, the piston pin 321 and one end of the connecting rod 322 are combined.

Therefore, the connecting rod 322 is coupled to the piston 32 in a relatively movable manner.

The connecting rod 322 converts the rotational motion of the rotary shaft 50 into the reciprocating motion of the piston 32.

The links 322 extend in one direction.

The link 322 is not limited to the illustrated form, and may be formed in various forms. For example, the link 322 may have an H-shaped cross section extending in a predetermined direction.

One end of the connecting rod 322 is coupled to the piston 32. Specifically, one end of the connecting rod 322 is coupled to the piston pin 321.

The other end of the link 322 is coupled to the rotary shaft 50 so as to be relatively rotatable.

In short, the connecting rod 322 is coupled to the piston 32 and the rotary shaft 50 by the piston pin 321 and the rotary shaft 50, respectively.

In one embodiment, a supply portion (not shown) of the oil 21 may be formed inside the connecting rod 322. At this time, the oil 21 supply portion forms a flow path for supplying the oil 21 to the interior of the piston 32.

Hereinafter, the driving motor 40 for supplying mechanical energy to the compression unit 30 will be described.

The driving motor 40 receives electric energy from the outside, converts it into mechanical energy, and transmits it to the compression part 30.

The drive motor 40 includes a stator 41 and a rotor 42.

The stator 41 is inserted into and fixed to the inner space of the housing 10.

The stator 41 is formed in a cylindrical shape.

The stator 41 includes a core and a coil wound around the core. At this time, the coil is electrically connected to an external power source of the reciprocating compressor 1.

The rotor 42 is rotatably provided inside the stator 41. Specifically, the rotor 42 is rotatably provided in a hollow portion formed in the center of the core of the stator 41.

A predetermined gap is formed between the outer periphery of the rotor 42 and the inner periphery of the stator 41. Therefore, the rotor 42 and the stator 41 do not collide during the rotation of the rotor 42.

The rotor 42 is formed in a cylindrical shape.

A permanent magnet is embedded in the rotor 42. At this time, the permanent magnets extend in the same direction as the extending direction of the rotor 42.

A rotation shaft 50 is coupled to the center of the rotor 42.

The rotary shaft 50 transmits the energy received from the driving motor 40 to the connecting rod 322 and the piston 32. Specifically, during driving of the driving motor 40, the rotary shaft 50 performs a rotational motion, and transmits mechanical energy to the connecting rod 322 and the piston 32. At this time, the piston 32 receiving the energy performs a reciprocating motion.

The rotation shaft 50 extends in a predetermined direction. The predetermined direction is a direction different from the extending direction of the links 322.

The rotary shaft 50 is coupled to the piston 32 via a connecting rod 322 so as to be relatively rotatable. Specifically, one end of the connecting rod 322 is coupled to the rotating shaft 50 so as to be relatively rotatable, and the other end of the connecting rod 322 is coupled to the piston 32.

The rotating shaft 50 includes a support portion 51, an eccentric portion 52, a balance portion 53, and an oil supply passage 54.

The support portion 51 is inserted into the rotor 42 and guides the rotational movement of the rotary shaft 50.

The support portion 51 is formed in a cylindrical shape extending in a predetermined direction.

The support portion 51 is rotatably inserted into the center portion of the bearing 313 of the cylinder block 31. At this time, the support portion 51 is radially supported by the bearing 313.

An eccentric portion 52 is formed at one end of the support portion 51. Specifically, the eccentric portion 52 is formed to be eccentric in the radial direction with respect to the support portion 51. That is, the center axis of the eccentric portion 52 and the center axis of the support portion 51 are not arranged on a straight line.

Therefore, during the rotation of the support portion 51, the eccentric portion 52 and the support portion 51 may rotate together.

The eccentric portion 52 is formed in a cylindrical shape extending in the same direction as the extending direction of the support portion 51. At this time, the eccentric portion 52 extends from the one end of the support portion 51 toward the opposite direction to the support portion 51.

A connecting rod 322 and a balancer 60 are coupled to an outer circumference of the eccentric portion 52.

The eccentric portion 52 is rotatable relative to the connecting rod 322. Conversely, during rotation of the eccentric portion 52, the balancer 60 and the eccentric portion 52 may rotate together.

In summary, during the rotation of the eccentric portion 52, although the balancer 60 rotates together with the eccentric portion 52, the connecting rod 322 does not rotate together with the eccentric portion 52 but performs an eccentric rotational motion.

A balance portion 53 is disposed between the eccentric portion 52 and the support portion 51.

The balancing portion 53 cancels a part of the unbalanced force generated during the movement of the piston 32 and the rotating shaft 50.

The balance part 53 is formed at the one end of the support part 51.

The balance portion 53 is formed to expand from the one end of the support portion 51 toward the radially outer side of the support portion 51.

An oil supply passage 54 is formed inside the support portion 51, the eccentric portion 52, and the balance portion 53.

The oil supply passage 54 supplies the oil 21 to the rotary shaft 50 to smoothly rotate the rotary shaft 50.

The oil supply passage 54 communicates with the inside of the oil supply device 20. Thereby, a movement passage of the oil 21 supplied from the oil storage space S4 to the rotary shaft 50 and the piston 32 through the oil supply device 20 is formed.

In an embodiment, the oil supply passage 54 may be connected with the connecting rod 322 and the oil 21 supply of the piston 32.

The rotating shaft 50 and the piston 32 may generate unbalanced forces during movement.

In order to reduce such unbalanced force, an additional balancer 60 is provided at the rotational shaft 50.

The balancer 60 is coupled to the rotating shaft 50 to rotate together with the rotating shaft 50.

The balancer 60 will be described in more detail later (refer to fig. 7 to 11).

Hereinafter, the coupling relationship between the piston 32, the rotary shaft 50, and the balancer 60 will be described in more detail with reference to fig. 2 to 6.

As described above, the piston 32 is coupled to the rotary shaft 50 via the connecting rod 322.

Specifically, one end of the connecting rod 322 is coupled to the piston 32, and the other end is coupled to the rotary shaft 50 so as to be relatively rotatable.

Further, a balancer 60 is coupled to the outer periphery of the rotary shaft 50. Specifically, the balancer 60 is coupled to the outer periphery of the eccentric portion 52.

The balancer 60 penetrates the eccentric portion 52 coupled to the rotating shaft 50 and rotates together with the rotating shaft 50.

At this time, the outer periphery of the rotary shaft 50 and the inner periphery of the coupling hole 611 of the balancer 60, which will be described later, are disposed adjacent to each other.

In one embodiment, the balancer 60 may be coupled to the outer circumference of the eccentric portion 52 by a thermal compression method.

In another embodiment, the balancer 60 can be coupled to the outer circumference of the eccentric portion 52 by inserting the eccentric portion 52 into the coupling hole 611.

The balancer 60 is not limited to the illustrated embodiment and may be formed in various forms.

In the illustrated embodiment, the balancer 60 is disposed above the links 322.

In an embodiment not shown, the balancer 60 may be disposed below the link 322.

Hereinafter, the balancer 60 will be described in more detail with reference to fig. 2 to 11.

The balancer 60 includes a coupling portion 61 and an eccentric mass portion 62.

The coupling portion 61 is a member directly coupled to the eccentric portion 52 of the rotary shaft 50.

The coupling portion 61 is formed in a plate shape having a predetermined cross section extending in the height direction of the rotary shaft 50.

The coupling portion 61 is formed to extend and expand toward the radially outer side of the eccentric portion 52.

The coupling portion 61 is coupled to an outer periphery of the eccentric portion 52.

A coupling hole 611 is formed through the center of the coupling portion 61.

The coupling hole 611 is a hollow hole having a predetermined cross section and extending in the height direction of the rotary shaft 50.

The inner circumferential surface of the coupling hole 611 is in contact with the outer circumferential surface of the eccentric portion 52. At this time, the inner circumference of the coupling hole 611 is formed in a shape corresponding to the outer circumference of the eccentric portion 52.

Therefore, the coupling portion 61 can be firmly coupled to the outer periphery of the eccentric portion 52.

In the illustrated embodiment, a protrusion formed to protrude toward the eccentric portion 52 is provided at the coupling hole 611. At this time, a plurality of the protrusions are provided at one coupling hole 611.

The protrusion is formed in a shape corresponding to a recess formed in the outer circumferential surface of the eccentric portion 52. Thus, the protrusion and the recess of the eccentric portion 52 can be engaged and coupled with each other.

That is, the coupling portion 61 and the eccentric portion 52 may be coupled in a concavo-convex manner. This prevents the balancer 60 from rotating relative to the eccentric portion 52 while the rotary shaft 50 is rotating.

The coupling hole 611 is not limited to the illustrated form and may be formed in various forms. For example, the coupling hole 611 may be a hollow hole having a circular cross section and extending in the height direction of the rotary shaft 50. At this time, the eccentric portion 52 is inserted into the coupling hole 611, whereby the coupling hole 611 can be coupled to the eccentric portion 52.

An eccentric mass portion 62 is coupled to one side of the coupling portion 61.

The eccentric mass portion 62 extends from the one side of the coupling portion 61 toward the radially inner side of the support portion 51.

In the illustrated embodiment, the eccentric mass portion 62 and the coupling hole 611 are spaced apart from each other. However, the eccentric mass portion 62 is not limited to the illustrated form, and may be formed in various forms. For example, the eccentric mass portion 62 may be disposed adjacent to the coupling hole 611.

In an embodiment of the present invention, one surface of the eccentric mass portion 62 opposite to the upper case 110 in the height direction of the rotation shaft 50 is inclined toward the opposite direction to the upper case 110. That is, the eccentric mass portion 62 is formed obliquely when viewed from the side (refer to fig. 2 and 7 to 9).

The one surface may be formed as a plane or a curved surface.

In the case where the one surface is formed in a curved surface, at least a portion of the one surface may be formed in a shape corresponding to the inner circumference of the upper case 110. Preferably, the entirety of the one surface may be formed in a shape corresponding to the inner circumference of the upper case 110.

In another embodiment of the present invention, one surface of the eccentric mass portion 62, which is opposite to the upper case 110 in the height direction of the rotating shaft 50, is bent toward the opposite direction to the upper case 110 by a prescribed angle. That is, when the eccentric mass portion 62 is viewed from the side, a part of the one surface is formed obliquely (refer to fig. 3 and 10).

In this case, the predetermined angle is greater than 0 degrees and less than 90 degrees.

In the one surface, a portion located radially outside the eccentric portion 52 with respect to the bending line may be formed as a flat surface or a curved surface.

In the case where the portion of the one surface is formed as a curved surface, the portion may be formed in a shape corresponding to an inner circumference of the upper case 110.

In the one surface, the remaining portion located radially inward of the eccentric portion 52 with respect to the bend line is formed as a flat surface.

At this time, the remaining portion of the one surface may be formed as a plane parallel to the radial direction of the eccentric portion 52.

In another embodiment of the present invention, the eccentric mass portion 62 and the protrusion portion 111 of the upper case 110 overlap in the height direction of the rotating shaft 50 (refer to fig. 4 and 11).

In the other embodiment, a protrusion 111 is formed at a portion of the upper case 110.

The projection 111 projects toward the opposite direction to the eccentric mass portion 62.

The projection 111 is formed in a shape corresponding to the eccentric mass portion 62.

In the embodiment shown in fig. 4 and 11, the upper surface and the lower surface of the eccentric mass portion 62 are formed as planes parallel to the radial direction of the eccentric portion 52. At this time, the projection 111 is formed in a shape corresponding to the eccentric mass portion 62.

However, the eccentric mass portion 62 and the projection 111 are not limited to the illustrated embodiment and may be formed in various forms.

In an embodiment not shown, one surface of the eccentric mass portion 62 opposite to the housing 10 in the height direction of the rotation shaft 50 may be bent toward the opposite direction to the housing 10, and the protrusion 111 may be formed in a shape corresponding to the eccentric mass portion 62.

As a result, in the embodiment of the present invention, the interval between the eccentric mass portion 62 and the inner periphery of the upper shell 110 can be further reduced.

In particular, when one surface of the eccentric mass portion 62 opposing the housing 10 in the height direction of the rotary shaft 50 is formed in a shape corresponding to the inner circumference of the housing 10, the interval between the eccentric mass portion 62 and the inner circumference of the upper shell 110 can be minimized.

Further, the weight center of the eccentric mass portion 62 can move toward the center axis of the support portion 51.

Therefore, when the rotating shaft 50 rotates, the absolute value of the balancing force generated by the balancer 60 can be further increased. That is, the balance force generated by the balancer 60 can be sufficiently secured when the reciprocating compressor 1 is driven.

Thereby, the driving force generated during the movement of the rotary shaft 50 and the piston 32 and the balancing force generated by the balancer 60 may be compensated for each other, enabling the total unbalance force to be further reduced.

Further, the vibration of the rotary shaft 50 and the piston 32 can be further reduced.

Further, noise caused by vibration can be further reduced.

As a result, the space between the balancer 60 and the upper housing 110 can be reduced, and the vibration of the rotary shaft 50 can be reduced while overcoming the design limitation of the balancer 60.

On the other hand, the interval of the eccentric mass part 62 from the inner circumference of the upper shell 110 may be adjusted according to a preset driving condition of the reciprocating compressor 1.

One surface of the eccentric mass portion 62, which is opposed to the upper case 110 in the height direction of the rotary shaft 50, is spaced apart from the inner circumference of the upper case 110.

The uppermost end of the one surface of the eccentric mass portion 62 in the height direction of the rotating shaft 50 is spaced apart from the inner circumference of the upper shell 110 in the height direction of the rotating shaft 50 by a first interval g 1.

That is, the first interval g1 is a distance between the uppermost end of the one surface and the inner circumference of the upper shell 110 in the height direction of the rotating shaft 50.

In addition, the lowermost end of the one surface of the eccentric mass portion 62 in the height direction of the rotating shaft 50 is spaced apart from the inner periphery of the upper shell 110 in the height direction of the rotating shaft 50 by a second gap g 2.

That is, the second interval g2 is a distance in the height direction of the rotary shaft 50 between the lowermost end of the one surface and the inner circumference of the upper shell 110.

At this time, a value obtained by dividing the first interval g1 by the second interval g2 is a preset prescribed interval ratio.

The prescribed interval ratio may be adjusted according to preset driving conditions of the reciprocating compressor 1.

Accordingly, the first and second intervals g1 and g2 may be formed as an interval ratio most suitable for a preset driving condition. That is, the predetermined interval ratio may be set to an interval ratio that is most suitable for a preset driving condition.

In one embodiment, the predetermined interval ratio is 0.9 or more and 1.1 or less.

In another embodiment, the one surface of the eccentric mass portion 62 is formed in a shape corresponding to the inner circumference of the upper case 110, and the prescribed space ratio is 1.

Hereinafter, a balancing process of the balancer 60 during the rotational movement of the rotational shaft 50 will be described in more detail with reference to fig. 12.

In the graph shown in fig. 12, a chain line indicates an unbalanced force Fun generated during the movement of the rotary shaft 50 and the piston 32, a broken line indicates a balanced force Fbw for canceling the unbalanced force, and a solid line indicates a resultant force of the unbalanced force Fun generated during the movement of the rotary shaft 50 and the piston 32 and the balanced force Fbw for canceling the unbalanced force, that is, a final unbalanced force Fun + Fbw.

As described above, the rotation shaft 50 performs a rotational motion by receiving mechanical energy from the driving motor 40.

Since the eccentric portion 52 is provided in the rotary shaft 50 and the piston 32 is coupled to one side of the rotary shaft 50, the rotary shaft 50 is unbalanced in weight.

Therefore, during the rotational movement of the rotary shaft 50, the rotary shaft 50 and the piston 32 rotate in an eccentric state. Thus, the rotary shaft 50 and the piston 32 may be vibrated by the centrifugal force. That is, during the rotational movement of the rotary shaft 50, an unbalanced force may be generated at the rotary shaft 50 and the piston 32.

In the graph shown in fig. 12, the unbalanced force Fun generated during the movement of the rotary shaft 50 and the piston 32 is an elliptical shape that is eccentric in a specific direction.

The balancer 60 may be coupled to the rotation shaft 50, or a balancing part 53 may be formed on the rotation shaft 50 by itself to offset an unbalanced force Fun generated during the movement of the rotation shaft 50 and the piston 32.

In the graph shown in fig. 12, the balancing force Fbw for canceling the unbalance force is a circle centered on the coordinates (0, 0).

As described above, in the embodiment of the present invention, the interval between the balancer 60 and the upper case 110 can be further reduced, and the weight center can be moved toward the central axis of the support 51.

Therefore, the mass point of the balancer 60 can be moved toward the center axis of the support 51.

This can further reduce the distance from the center axis of the support 51 to the mass point of the balancer 60.

As a result, the size of Fbw can be increased.

In the graph shown in fig. 12, the magnitude of the final unbalanced force Fun + Fbw does not greatly deviate when compared with the conventional balancer.

That is, when compared with the existing balancer, the unbalance force Fun generated during the movement of the rotary shaft 50 and the piston 32 is sufficiently compensated by the balance force Fbw for canceling the unbalance force.

At this time, the final unbalanced force Fun + Fbw cannot be 0, and the design is performed in a direction to minimize this.

As described above, in the reciprocating compressor 1 of the present invention, the absolute values of Fbwx and Fbwy can be further increased.

Therefore, the absolute value of Funx + Fbwx can be increased, and the absolute value of funny + Fbwy can be decreased. That is, the variation in the magnitude of the final unbalance force Fun + Fbw can be further reduced.

Thereby, the vibration and noise generated by the rotary shaft 50 and the piston 32 during the rotary motion of the rotary shaft 50 can be further reduced.

The present invention has been described above with reference to preferred embodiments thereof, but the present invention is not limited to the configurations of the above-described embodiments.

In addition, those skilled in the art can make various modifications and alterations to the present invention without departing from the scope and spirit of the present invention as set forth in the appended claims.

Further, a plurality of the embodiments may be configured by selectively combining all or a part of the respective embodiments to realize various modifications.

Claims

1. A reciprocating compressor, comprising:

a piston;

a rotating shaft coupled to the piston so as to be rotatable relative to the piston;

a balancer that is coupled to the rotating shaft and rotates together with the rotating shaft; and

a housing accommodating the piston, the rotary shaft, and the balancer therein,

the rotating shaft includes:

a support part extending in one direction; and

an eccentric portion formed to extend in the one direction from one end of the support portion, and a central axis of the eccentric portion and a central axis of the support portion are not arranged on a straight line,

the balancer includes:

a coupling portion formed by extending and expanding from a coupling hole contacting an outer circumferential surface of the eccentric portion toward a radial outer side of the eccentric portion; and

an eccentric mass part coupled to one side of the coupling part, extending toward a radially inner side of the support part, and one surface of the eccentric mass part opposite to the housing in a height direction of the rotation shaft is inclined toward a direction opposite to the housing.

2. The reciprocating compressor of claim 1, wherein,

the one surface of the eccentric mass portion is formed as a curved surface.

3. The reciprocating compressor of claim 2, wherein,

at least a portion of the one surface of the eccentric mass portion is formed in a shape corresponding to an inner circumferential surface of the housing.

4. The reciprocating compressor of claim 1, wherein,

the one surface of the eccentric mass portion is formed as a plane.

5. The reciprocating compressor of claim 1, wherein,

an uppermost end of the one surface of the eccentric mass portion in a height direction of the rotating shaft is spaced apart from an inner circumferential surface of the housing by a first interval in the height direction of the rotating shaft,

a lowermost end of the one surface of the eccentric mass portion in a height direction of the rotating shaft is spaced apart from an inner circumferential surface of the housing by a second interval in the height direction of the rotating shaft,

a value obtained by dividing the first interval by the second interval is a preset predetermined interval ratio.

6. The reciprocating compressor of claim 5,

the predetermined spacing ratio is 0.9 or more and 1.1 or less.

7. A reciprocating compressor, comprising:

a piston;

a rotating shaft extending in one direction and coupled to the piston so as to be rotatable relative to the piston;

a balancer coupled to an outer circumference of the rotating shaft and rotating together with the rotating shaft; and

a housing accommodating the piston, the rotary shaft, and the balancer therein,

the rotating shaft includes:

a support portion extending in the one direction; and

the balancer includes:

an eccentric mass part coupled to one side of the coupling part and extending toward a radial inner side of the support part,

one surface of the eccentric mass portion facing the housing in a height direction of the rotating shaft is bent at a predetermined angle in a direction opposite to the housing.

8. The reciprocating compressor of claim 7,

in the one surface of the eccentric mass portion, a portion located radially outside the eccentric portion is formed as a curved surface with reference to a bending line.

9. The reciprocating compressor of claim 8,

the portion of the eccentric mass portion is formed in a shape corresponding to an inner circumferential surface of the housing.

10. The reciprocating compressor of claim 7,

in the one surface of the eccentric mass portion, a portion located radially outside the eccentric portion is formed as a flat surface with reference to a bending line.

11. The reciprocating compressor of claim 7,

12. The reciprocating compressor of claim 11, wherein,

the predetermined spacing ratio is 0.9 or more and 1.1 or less.

13. A reciprocating compressor, comprising:

a piston formed in a cylindrical shape;

a housing accommodating the piston, the rotating shaft, and the balancer therein, a protrusion being formed at a portion of the housing,

the rotating shaft includes:

a support part extending in one direction; and

the balancer includes:

the protrusion portion and the eccentric mass portion are overlapped in a height direction of the rotating shaft, the protrusion portion protrudes toward a direction opposite to the eccentric mass portion, and the protrusion portion is formed in a shape corresponding to the eccentric mass portion.

14. The reciprocating compressor of claim 13,

the rotating shaft includes a balance portion disposed between the support portion and the eccentric portion and formed to be expanded from the one end of the support portion toward a radially outer side of the support portion.

15. The reciprocating compressor of claim 14, wherein,

the piston includes a connecting rod extending in a direction different from the one direction, one end of the connecting rod is coupled to the piston, and the other end thereof is coupled to the eccentric portion so as to be rotatable with respect to the eccentric portion.