BACKGROUND ART In general, a reciprocating compressor compresses refrigerant gas by a linear reciprocating motion of a piston combined to a magnet and coil assembly in place of a crank shaft.

As depicted in Figure 1, a reciprocating compressor in accordance with the prior art includes a compressing unit C horizontally installed inside a casing V containing lubricant at a lower portion and sucking, compressing and discharging a refrigerant, and a lubricant supplying apparatus O fixed to the external of the compressing unit C and supplying lubricant.

As depicted in Figure 2, the lubricant supplying apparatus O includes a lubricant cylinder 21 installed at the bottom surface of the compressing unit C, a lubricant piston 22 inserted inside the lubricant cylinder 21 and dividing inward of the lubricant cylinder 21 into a suction area S1 and a discharge area S2, a first lubricant spring 23A and a second lubricant spring 23B elastically supporting both ends of the lubricant piston 22 at the end of the lubricant cylinder 22, a lubricant suction valve 24 installed at an outlet end of the lubricant piston 22 and supported by the second lubricant spring 23B, and a lubricant discharge valve 25 installed at an outlet side of the lubricant cylinder 21.

The lubricant piston 22 is slide-inserted into the lubricant cylinder 21 so as to be its outer circumference contacted to the inner circumference of the lubricant cylinder 21, and a lubricant passage 22a is formed inward of the lubricant cylinder 21 by penetrating the lubricant cylinder 21 from an inlet to an outlet.

The lubricant suction valve 24 is compressed and supported by the second lubricant spring 23B at a section of the outlet of the lubricant piston 22 so as to open and shut the lubricant passage 22a formed inward of the lubricant piston 22.

In drawings, a unexplained reference numeral 1 is a frame, 1 a is a lubricant suction channel, 3 is a cylinder, 4 is an inner stator and an outer stator, 5 is a mover, 6 is a piston, 7 is a suction valve, 8 is a discharge valve assembly, 9 is a suction pipe, 26 is a suction cover, 27 is a discharge cover, S1 is a suction area, and a S2 is a discharge area.

The operation of the lubricant supplying apparatus of the reciprocating compressor in accordance with the prior art will now be described.

In a linear reciprocating motion of the mover 5 of a reciprocating motor, the compressing unit C vibrates horizontally with the mover 5, etc., the

vibration is transmitted to the lubricant cylinder 21 fixed to the compressing unit C, accordingly the lubricant cylinder 21 performs a linear reciprocating motion. Herein, the lubricant piston 22 slide-inserted into the lubricant cylinder 21 sucks and discharges lubricant by performing a motion inside the lubricant cylinder 21 due to an inertia force opposed to the reciprocating motion of the lubricant cylinder 21.

First, as depicted in Figure 2A, when the lubricant cylinder 21 moves to a"P"direction, the lubricant piston 22 moves in a direction opposite to a motion of the lubricant cylinder 21 by surmounting the first lubricant spring 23A, a pressure of the discharge area S2 is lower than a pressure of the suction area S1, lubricant of the suction area S1 flows to the discharge area S2 through the lubricant passage 22a. Herein, the lubricant suction valve 24 is open, on the contrary the lubricant discharge valve 25 returns and shuts the discharge side of the lubricant cylinder 21, accordingly a back flow of lubricant is prevented.

In the meantime, as depicted in Figure 2B, when the lubricant cylinder 21 moves to a"Q"direction, the lubricant piston 22 moves in a direction opposite to a motion of the lubricant cylinder 21 by surmounting the second lubricant spring 23B, pushes lubricant filled inside the discharge area S2, at the same time lubricant is filled in the suction area S1 by flowing through a gap between the lubricant cylinder 21 and a lubricant suction cover 26.

Herein, the lubricant passage 22a of the lubricant piston 22 is shut by shutting the lubricant suction valve 24. On the contrary the lubricant discharge valve 25 is open, accordingly the discharge side of the lubricant cylinder 21 is open.

However, the lubricant supplying apparatus of the reciprocating compressor in accordance with the prior art has below problems, First, in the lubricant supplying apparatus of the reciprocating compressor in accordance with the prior art, a lubricant suction channel and a lubricant discharge channel are separately placed at both sides of a lubricant piston, lubricant is guided from a suction area to a discharge area through a lubricant passage formed inside the lubricant piston.

In this case, because the lubricant passage has to be formed inside the lubricant piston as small as possible, it is difficult to fabricate the lubricant passage. When a diameter of the lubricant passage increases in order to facilitate a fabrication, a size of the lubricant piston increases, accordingly a compact lubricant supplying apparatus can not be provided.

In addition, because a size of a lubricant suction valve controlling suction and discharge of lubricant is small, a manual operation is not easy in assembly and a productivity lowers, because an opening and shutting portion (not shown) of the lubricant suction valve is bridged in a compression coil spring supporting a lubricant piston, suction and discharge of lubricant can not be controlled appropriately or a smooth operation can not be performed by impurities stuck to the lubricant suction valve, accordingly a reliability of parts lowers.

In addition, because lots of parts are required in order to construct a lubricant supplying apparatus, the number of assembly process is increased, accordingly its productivity is decreased.

TECHNICAL GIST OF THE PESENT INVENTION Accordingly, in order to solve above-mentioned problems, it is an object of the present invention to provide a lubricant supplying apparatus of a reciprocating compressor which is capable of supplying lubricant smoothly without forming a lubricant passage in a lubricant piston in order to maintain compact structure.

In addition, it is another object of the present invention to provide a lubricant supplying apparatus of a reciprocating compressor which is capable of supplying lubricant appropriately by simplifying an assembly and preventing parts from being interfered by other parts.

It is still another object of the present invention to provide a lubricant supplying apparatus of a reciprocating compressor which is capable of improving a productivity by simplifying an assembly by decreasing the number of parts.

In order to achieve the above-mentioned objects, in a lubricant supplying apparatus of a reciprocating compressor including a reciprocating motor having a mover coming and going between an inner stator and an outer stator, a compressing unit having a cylinder and a lubricant guide passage guiding lubricant inside the cylinder, and a piston connected to the mover and compressing a refrigerant while sliding inside the cylinder, there is provided a lubricant supplying apparatus of a reciprocating compressor comprising a hollow lubricant cylinder having an inward space, a lubricant piston installed inside the lubricant cylinder and sliding inside, a lubricant suction channel

connected to the inward space of the lubricant cylinder so as to suck lubricant stored in a container of a reciprocating compressor, a lubricant discharge channel connected to the inward space of the lubricant cylinder so as to discharge lubricant, and wherein the lubricant suction passage and the lubricant discharge passage are placed at a side of the lubricant cylinder centering around the lubricant piston.

In addition, in a lubricant supplying apparatus of a reciprocating compressor including a reciprocating motor having a mover coming and going between an inner stator and an outer stator, a compressing unit having a cylinder and a lubricant guide passage guiding lubricant inside the cylinder, and a piston connected to the mover and compressing a refrigerant while sliding inside the cylinder, there is provided a lubricant supplying apparatus of a reciprocating compressor comprising a hollow lubricant cylinder having an inward space, a lubricant piston placed inside the lubricant cylinder and sliding inside, a lubricant suction channel connected to the inward space of the lubricant cylinder so as to suck lubricant stored in a container of a reciprocating compressor, a lubricant discharge channel connected to the inward space of the lubricant cylinder so as to discharge lubricant, a lubricant valve unit having a lubricant suction valve and a discharge valve, a lubricant suction passage and a lubricant discharge passage and a valve cover, and wherein the lubricant suction passage and the lubricant discharge passage are placed at a side of the lubricant cylinder centering around the lubricant piston and the lubricant valve unit is placed at the outward of the lubricant cylinder.

BRIEF DESCRIPTION OF DRAWINGS Figure 1 is a longitudinal sectional view illustrating a reciprocating compressor in accordance with the prior art.

Figure 2A is a longitudinal sectional view illustrating the operation of the lubricant supplying apparatus of the reciprocating compressor in accordance with the prior art.

Figure 2B is a longitudinal sectional view illustrating the operation of the lubricant supplying apparatus of the reciprocating compressor in accordance with the prior art.

Figure 3 is a longitudinal sectional view illustrating embodiment of a reciprocating compressor including a lubricant supplying apparatus in accordance with the present invention.

Figure 4 is a disassembled-perspective view illustrating a lubricant supplying apparatus of a reciprocating compressor in accordance with a first embodiment of the present invention.

Figure 5 is a perspective view illustrating another embodiment of a lubricant valve in accordance with the first embodiment of the present invention.

Figure 6 is a perspective view illustrating another embodiment of a lubricant discharge channel formed at a passage member in accordance with the first embodiment of the present invention.

Figure 7 is a perspective view illustrating another embodiment of a

valve cover in accordance with the first embodiment of the present invention.

Figure 8 is a partial sectional view illustrating a lubricant supplying apparatus of a reciprocating compressor in accordance with a second embodiment of the present invention.

Figure 9 is a partial sectional view illustrating another embodiment of a lubricant supplying apparatus of a reciprocating compressor in accordance with the second embodiment of the present invention.

Figure 10 is a longitudinal sectional view illustrating a lubricant supplying apparatus of a reciprocating compressor in accordance with a third embodiment of the present invention.

Figure 11 A is a longitudinal sectional view illustrating the operation of the lubricant supplying apparatus of the reciprocating compressor in accordance with the present invention.

Figure 11 B is a longitudinal sectional view illustrating the operation of the lubricant supplying apparatus of the reciprocating compressor in accordance with the present invention.

DETAILED DESCRIPTION OF THE INVENTION Hereinafter, a lubricant supplying apparatus of a reciprocating compressor in accordance with the present invention will now be described in detail with reference to accompanying drawings.

In describing reference numerals, parts same as the prior art will have the same reference numerals, and descriptions overlapped with the prior art

will be abridged.

First, a first embodiment of a lubricant supplying apparatus of a reciprocating compressor in accordance with the present invention will now be described.

As depicted in Figures 3 and 4, a reciprocating compressor including a lubricant supplying apparatus in accordance with the present invention includes a compressing unit C transversely installed inside a casing V filled with lubricant at the bottom and compressing and discharging a refrigerant after sucking the refrigerant, and a lubricant supplying apparatus O fixed to the outward of the compressing unit C and supplying lubricant.

The lubricant supplying apparatus O includes a lubricant cylinder 110 installed to the bottom surface of a frame 1 supporting the compressing unit C, a lubricant piston 120 slide-inserted into the lubricant cylinder 110 and inducing a pressure change inside the lubricant cylinder 110 in vibration of the compressing unit C, a rectangular lubricant valve 130 having a lubricant suction valve 131 and a lubricant discharge valve 132 fixed to the front surface of the frame 1 and open/shut alternately according to a pressure variation of the lubricant cylinder 110, a passage member 140 having a plate body corresponded to the lubricant valve 130, a suction port 141 and a discharge port 142 formed at the plate body, a lubricant suction channel 143 extended formed at the suction port 141 and a lubricant discharge channel 144 extended formed at the discharge port 142, and a valve cover 150 covering and supporting the lubricant valve 130 and the lubricant member 140.

A suction valve movable region 1A connected to the suction port 141 of the valve cover 150 is formed at the front surface of the frame 1, and a discharge valve movable region 1B connected to the discharge port 142 of the valve cover 140 is formed at the upper portion of the suction valve movable region 1A. A cross wall 1C is formed between the suction valve movable region 1A and the discharge valve movable region 1B in order to divide the regions, accordingly sucked lubricant and lubricant to be discharged can be divided. And, a back flow of discharge lubricant can be prevented.

A compressed-type coil springs 160A, 160B are placed inside the lubricant cylinder 110 in order to elastically support both ends of the lubricant piston 120.

And, a cylinder cover 110a having a through hole 110b is installed at the end of the lubricant cylinder 110 for smooth flow of lubricant And, the lubricant piston 120 is formed as a rod shape, and the outer circumference of the lubricant piston 120 is contacted to the inner circumference of the lubricant cylinder 110 when it is slide-inserted into the lubricant cylinder 110.

A main body of a lubricant valve 130 is a rectangular plate having a certain thickness, a lubricant suction valve 131 and a lubricant discharge valve 132 are separately punched-formed at the upper portion and lower portion centering around the middle portion of the main body.

The lubricant suction valve 131 is constructed with an elastic supporting portion 131 a having a narrow width and a covering portion 131 b

having a round plate shape connected to the elastic supporting portion 131 a.

The lubricant suction valve 131 is formed by being separated from the main body of the lubricant valve 130. A diameter of the covering portion 13b is formed so as to be larger than a diameter of the suction port 141 formed at the passage member 140 in order to control a flow of lubricant passing through the suction port 141.

In addition, a lubricant opening 130a is formed at both sides of the lubricant suction valve 131 between the main body of the lubricant valve 130 and the lubricant suction valve 131 in order to make lubricant flow by connecting the suction valve movable region 1A of the frame 1 to the discharge port 142 of the passage member 140.

And, in combination of the passage member 140 and the lubricant valve 130, the elastic supporting portion 131 a of the lubricant valve 130 is placed onto the lubricant discharge channel 144.

And, the lubricant discharge valve 132 is punched-formed on the main body of the lubricant valve 130 so as to be a rectangular shape and has a width d capable of shutting sufficiently the discharge port 142 formed at the passage member 140.

And, the circular discharge port 142 and the circular suction port 141 are separately formed at the upper and lower portions of the passage member 140, the lubricant discharge channel 144 is formed by contacting to the discharge port 142 so as to be grooved in a vertical direction, and the lubricant suction channel 143 is formed by contacting to the suction port 141 so as to be grooved in a vertical direction. And, the lubricant discharge

channel 144 is placed onto the lubricant opening 130a formed between the lubricant suction valve 131 and the valve plate 133.

The valve cover 150 is formed as a rectangular shape corresponded to the shape of the passage member 140 and support the lubricant valve 130 and the passage member 140.

In addition, the valve cover 150, the passage member 140 and the lubricant valve 130 are combined to the frame 1 by fastening a plurality of combining holes 152,153,154 punched on the outer circumference of them to a fastening hole 151 punched on the front surface of the frame 1 with an appropriate fastening member.

And, in another embodiment of the lubricant valve 130 in accordance with the first embodiment of the present invention as depicted in Figure 5, the valve plate 133 itself is constructed with a upper valve plate 233a and a lower valve plate 233b, the lubricant discharge valve 232 is formed at the upper valve plate 233a, and the lubricant suction valve 231 is formed at the lower valve plate 233b.

And, in another embodiment of a lubricant member 240 in accordance with the first embodiment of the present invention as depicted in Figure 6, a lubricant discharge channel 244 is wholly connected to a upper discharge port 242 and penetrates the passage member 240.

And, a width d'of the discharge port 242 penetrating the passage member 240 is smaller than a width d of the lubricant discharge valve 132, and its length is shorter than a length of the lubricant discharge valve 132.

And, in another embodiment of a valve cover 250 in accordance with

the first embodiment of the present invention as depicted in Figure 7, the lubricant suction channel 143 is formed at the valve cover 150 by being grooved on behalf of being formed at the lower portion of the passage member 140.

Parts same as the parts in the prior art will have the same reference numerals.

A unexplained reference numeral 1 is a frame, 1 a is a lubricant suction channel, 3 is a cylinder, 4 is an inner and outer stators, 5 is a mover, 6 is a piston, 7 is a suction valve, 8 is a discharge valve assembly and 9 is a suction pipe.

The operation of the lubricant supplying apparatus of the reciprocating compressor in accordance with the present invention will now be described in detail.

When the frame supporting the compressing unit C vibrates in a horizontal direction, the lubricant cylinder 110 formed at the frame 1 also vibrates in a horizontal direction, a pressure difference occurs while the lubricant piston 120 inserted into the lubricant cylinder 110 has an inertia force opposite to the reciprocating movement of the lubricant cylinder 110, lubricant filled in a casing V is sucked or discharged by the pressure difference.

It will now be described in more detail.

First, as depicted in Figure 11A, when the lubricant cylinder 110 moves in a"P"direction, the lubricant piston 120 moves in a direction opposite to the direction of the lubricant cylinder 110, an inward space T2 of the lubricant cylinder 110 is relatively in a low pressure state.

Herein, the suction port 141 of the passage member 140 is open while the cover portion 131 b of the lubricant suction valve 131 of the lubricant valve 130 is pushed by a pressure of lubricant, lubricant is sucked through the open suction port 141 and fills the suction valve movable region 1A of the frame 1 and the lubricant cylinder 110.

Next, as depicted in Figure 11B, when the lubricant cylinder 110 moves in a"Q"direction, the lubricant piston 120 moves in a direction opposite to the direction of the lubricant cylinder 110, the inward space T2 of the lubricant cylinder is relatively in a high pressure state.

At this time, lubricant in the lubricant cylinder 110 and the suction valve movable region 1A of the frame 1 pushes the lubricant discharge valve 132 while moving to the discharge port 142 of the passage member 140 through the lubricant opening 130a, the lubricant discharge valve 132 is open, lubricant in the discharge port 142 is supplied to each part of the compressing unit C according to the lubricant suction channel 1a. At the same time, the cover portion 131 b of the lubricant suction valve 131 of the lubricant valve 130 shuts the suction port 141 by being pushed by a high pressure occurred in the lubricant cylinder 110, the suction of lubricant is shut off.

As described above, the suction valve and the discharge valve are formed as a plate-shaped lubricant valve, the lubricant valve is installed at the side of the frame on behalf of being installed inward portion of a lubricant cylinder having the lower diameter, it is advantageous to fastening and assembling of each part.

Hereinafter, a second embodiment of a lubricant supplying apparatus

of a reciprocating compressor in accordance with the present invention will now be described.

As depicted in Figure 8, in a second embodiment of a lubricant supplying apparatus of a reciprocating compressor, a connection passage is included, its end is connected to the inward space 220 of the lubricant cylinder 310 and its other end is connected to the lubricant suction channel 343 and the lubricant discharge channel 344.

In more detail, the second embodiment of the lubricant supplying apparatus of the reciprocating compressor includes a suction valve movable region 1A connected to the connection passage 210, a discharge valve movable region 1 B connected to the lubricant suction passage 1 a, a lubricant suction valve 331 and a lubricant discharge valve 332 placed at the valve movable region, and a valve cover 350 having a lubricant suction channel 343 and a lubricant discharge channel 344.

Herein, the lubricant suction channel 343 and the lubricant discharge channel 343 can be constructed as an additional member.

Figure 9 illustrates another embodiment of a lubricant supplying apparatus of a reciprocating compressor in accordance with the second embodiment of the present invention. A lubricant suction valve 431 and a lubricant discharge valve 432 are separately placed onto a lubricant suction channel 443 and a lubricant discharge channel 444 and are open and shut selectively.

As described above, by owning the connection passage 210 jointly in suction and discharge of lubricant, it is advantageous to installing the lubricant

suction valve and the lubricant discharge valve at the exterior of the lubricant cylinder 310.

Hereinafter, a third embodiment of the lubricant supplying apparatus of the reciprocating compressor in accordance with the present invention will now be described.

As depicted in Figure 10, the lubricant supplying apparatus 0 includes a lubricant cylinder 510 installed at the bottom surface of the frame 1 supporting the compressing unit C, a lubricant piston 520 slide-inserted into the lubricant cylinder 510 and generating a pressure difference inside the lubricant cylinder 510 in vibration of the compressing unit C, a lubricant valve 530 fixed to the front surface of the frame 1 and having a lubricant suction valve 531 and a lubricant discharge valve 532 which are crossly open and shut in accordance with the pressure difference of the lubricant cylinder 510, and a valve cover 550 fixed to the front surface of the frame 1 by covering the lubricant valve 530 and having a suction port 541 and a discharge port 542.

The suction valve movable region 1A connected to the suction port 541 of the valve cover 550 is formed inward portion of the frame 1, above the suction valve movable region 1A and the discharge valve movable region 1 B connected to the discharge port 542 of the valve cover 540 is formed inward portion of the frame 1. A cross wall 1 C is formed between the suction valve movable region 1A and the discharge valve movable region 1 B in order to divide them, accordingly sucked lubricant and lubricant to be discharged can be divided without being mixed. And, a back flow of discharge lubricant can be prevented.

Compressed-type coil springs 160A, 160B are included at inner both ends of the lubricant cylinder 510 in order to support both ends of the lubricant piston 520. A cylinder cover 51 Oa having a through hole 51 Ob is formed at the end of the lubricant cylinder 510 for the smooth flow of lubricant.

And, the lubricant piston 520 is formed as a rod shape, and the outer circumference of the lubricant piston 520 is contacted to the inner circumference of the lubricant cylinder 110 when it is slide-inserted into the lubricant cylinder 110.

A main body of a lubricant valve 530 is a rectangular plate having a certain thickness, a lubricant suction valve 531 and a lubricant discharge valve 532 are separately punched-formed at the upper portion and lower portion centering around the middle portion of the main body.

The lubricant suction valve 531 is constructed with an elastic supporting portion 531 a having a narrow width and a covering portion 531 b having a round plate shape connected to the elastic supporting portion 531 a, the lubricant suction valve 531 is formed by being punched on the main body of the lubricant valve 530. A diameter of the covering portion 531 b is formed so as to be larger than a diameter of the suction port 541 formed at the valve cover 550 in order to control the flow of lubricant passing through the suction port 541.

In addition, a lubricant opening 530a is formed at both sides of the lubricant suction valve 531 between the main body of the lubricant valve 530 and the lubricant suction valve 531 in order to make lubricant flow by connecting the suction valve movable region 1A of the frame 1 to the

discharge port 542 of the valve cover 540.

And, the lubricant discharge valve 532 is punched-formed on the main body of the lubricant valve 530 so as to be a rectangular shape and have a length and a width capable of shutting sufficiently the upper portion 542a of the discharge port 542 formed at the valve cover 540, the lower portion 542b of the discharge port 542 is placed on the lubricant opening 530a formed between the lubricant suction valve 531 and the valve main body.

In the valve cover 540, a circular suction port 541 is formed at the lower center portion so as to have a diameter smaller than a diameter of the covering portion 531 b of the lubricant suction valve 531, and a discharge port 542 is protrusively formed at the center upper portion so as to be a long groove shape having a certain volume and have a width and a length smaller than the lubricant discharge valve 532 of the lubricant valve 530.

In addition, the valve cover 550 and the lubricant valve 530 are combined to the frame 1 by fastening a plurality of fastening holes 552,553 formed at the outer circumference of them to a plurality of fastening holes 551 formed at the front surface of the frame 1 with an appropriate fastening means.

The operation of the third embodiment of the lubricant supplying apparatus of the reciprocating compressor is same as the first embodiment of the lubricant supplying apparatus of the reciprocating compressor.

INDUSTRIAL APPLICABILITY

Hereinafter, advantages of a first embodiment of a lubricant supplying apparatus of a reciprocating compressor will now be described.

Because a lubricant suction channel and a lubricant discharge channel are formed at one side centering around a lubricant piston, lubricant can be supplied without forming a lubricant passage at the lubricant piston, accordingly it is advantageous to a miniaturization of a lubricant supplying apparatus and a retrenchment of the unit cost of production by simplifying a process.

In addition, by placing the lubricant suction valve and the lubricant discharge valve at the exterior of the lubricant cylinder on behalf of placing them inside the lubricant cylinder, the process and assembly of the lubricant suction valve and the lubricant discharge valve can be easier, accordingly it is advantageous to reducing the unit cost of production and improving a productivity. And, because a gap between the lubricant valve and the valve seat is bigger, impurities does not got caught, because there is no elastic member inserted inside the lubricant cylinder, the lubricant valve does not be interfered by the elastic member, accordingly a reliability of the lubricant supplying apparatus of the reciprocating compressor increases.

A suction valve and a discharge valve are constructed as a lubricant valve having a plate shape, the lubricant valve is assembled to the side surface of the frame on behalf of being assembled inside the lubricant cylinder having a small diameter, it is advantageous to fabricating and assembling each part.

Hereinafter, an effect of the third embodiment of the lubricant supplying

apparatus of the reciprocating compressor will now be described.

By constructing a valve cover including a suction port open and shut by a lubricant suction valve of a lubricant valve and a discharge port open and shut by a lubricant discharge valve of the lubricant valve, an assembly can be simplified by reducing the number of parts, a productivity increases by simplifying the process and assembly, and a reliability of the lubricant supplying apparatus of the reciprocating compressor increases by stabilizing a movement of the lubricant valve.