Patent Publication Number: US-11022116-B2

Title: Lubricant supply device and a compressor using the same

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     The present application claims priority to and the benefit of Korean Patent Application No. 10-2018-0007370, filed on Jan. 19, 2018, the disclosure of which is incorporated herein by reference in its entirety. 
     FIELD 
     The present disclosure relates to a lubricant supply device used for a compressor or the like. 
     BACKGROUND 
     A compressor is a device that increases pressure by compressing gas. In a method in which the compressor compresses the gas, there are a reciprocating compression method that compresses and discharges gas suctioned into a cylinder by a piston and a scroll compression method that compresses gas by relatively rotating two scrolls, etc. 
     The compressor is provided with a rotational shaft that provides force that compresses the gas. Since the compressor is provided with a large number of mechanical elements that mutual friction occurs, lubrication therefor is required. 
     Hereinafter, the related art of the present disclosure will be described with reference to  FIGS. 1 to 4 . 
     Referring to  FIG. 1 , a reciprocating compressor has a structure in which a frame  20  is accommodated inside a housing  10 . The frame  20  supports a rotational shaft  50 . A lubricant supply flow path  53  is provided inside the rotational shaft  50  and a lubricant supplier  60  is installed at a lower end of the rotational shaft  50 . Lubricant is stored in a lower portion of an inner space of the housing  10 , and a lower end of the lubricant supplier  60  is submerged in the lubricant. 
     The lubricant supplier  60  includes a rotator  62  that rotates with the rotational shaft  50  and a fixer  61  that is fixed to the frame  20  and does not rotate. The rotator  62  is accommodated inside the fixer  61 . 
     The fixer  61  is installed in a state of being connected to a frame  20  by a fixed connection member  619 , and even if the rotational shaft  50  rotates, the fixer  61  does not rotate with the rotational shaft  50  and maintains a state of being fixed to the frame  20 . 
     The rotator  62  includes a first rotator  621  that penetrates a cover of the fixer  61  and is accommodated in a space inside the fixer  61 , and a second rotator  622  that surrounds an outer circumferential surface of the rotator  621  in the fixer  61  and is accommodated in the accommodation space  615  of the fixer  61 . A shaft coupler  626  which is press-fitted to an inner circumferential surface of a lubricant supply flow path  53  formed through the longitudinal direction of a rotational shaft  50  is formed integrally at an upper portion of the first rotator  621 . A part of the first rotator  621  is tooth-engaged with a part of the second rotator  622  and a predetermined rotator space  625  is provided where they are not tooth-engaged therebetween. 
     As the rotational shaft  50  rotates, the first rotator  621  whose shaft coupler  626  is press-fitted to the lubricant supply flow path  53  of the rotational shaft  50  rotates and the second rotator  622  also rotates. Then, oil flowed in the fixer through an oil inlet  617  of the fixer  61  moves to an oil chamber  618  while being trapped in a rotator space  625 . The volume of the rotator space  625  existing in adjacent to the oil inlet  617  gradually decreases as the rotator  62  rotates and moves to the direction of the oil chamber  618 . Thus, the oil filled in the rotator space  625  is pressurized and pushed into the oil chamber  618  of the fixer  61  and the oil pushed into the oil chamber  618  is pumped upward again through an oil outlet  629  of the rotator  62 . 
     Meanwhile, according to a structure of such a lubricant supply device, as shown in  FIGS. 3 and 4 , the distance d 1  between a rotator space  625  and a through-hole  616  of a cover  612  is very narrow. Thus, a phenomenon in which oil pressurized in the rotator space  625  leaks out through a gap between an outer circumferential surface of an oil outlet  629  and a through-hole  616  via a gap between an upper surface of a first rotator  621  and a cover  612  occurs. 
     In addition, in the lubricant supply device, the distance d 2  between an oil outlet  629  and an oil inlet  617  is also very narrow. Thus, a phenomenon in which high pressure oil that flows through the oil outlet  629  also leaks again adjacent to the oil inlet  617  through a gap between a lower surface of the first rotator  621  and the bottom  614  of a body  611  occurs. 
     In order to secure a wide distance d 1  between a through-hole  616  of the cover  612  and a rotator space  625  to prevent the oil leakage phenomenon as described above, the diameter of a shaft coupler  626  and the diameter of the through-hole  616  of an outer diameter cover  612  can be reduced or the outer diameter of the first rotator  621  can be increased. Further, in order to secure the wide distance d 2  between the oil outlet  629  and the oil inlet  617 , the outer diameter of the shaft coupler  626  can be reduced or the outer diameter of the first rotator  621  can be increased. 
     However, since a rotational shaft  50  is a part in which the diameter in certain degree has to be secured, there is a limitation to reduce the outer diameter of a shaft coupler  626 . Further, when increasing the outer diameter of the first rotator  621 , the diameters of a second rotator  622  and a fixer  61  have to be significantly increased accordingly. This result in decreasing an efficiency of the compressor since more power for a rotating the rotational shaft for compressing a refrigerant is consumed as power for supplying lubricant. 
     Thus, the above mentioned method for preventing oil leakage of oil results in a yet another side effect. 
     Meanwhile, in the oil pump structure described above, even if the first rotator  621  and the second rotator  622  rotate, the rotator space  625  does not deviate at the position shown if  FIG. 4 . Therefore, when the rotator space  625  moves clockwise from the left to the right, the volume thereof gradually decreases. And when the rotator space  625  moves clockwise from the right to the left, the volume thereof increases. According to this method, oil in the rotator space  625  in the wide volume can be pumped by the gradually narrowing volume only when the rotation direction of a rotational shaft is clockwise. That is, when the rotational shaft rotates in the opposite direction due to a cause for connecting the power source for a motor that rotates the rotational shaft to the opposite polarity, etc., the oil pump structure cannot supply the oil. 
     The reciprocating compressor is advantageous in that a compressor operates regardless of the rotation direction of the rotational shaft. However, when the structure in which the oil is supplied only when it is rotated in any one direction as described above is applied to the reciprocating compressor, the above described advantage of the reciprocating compressor cannot be exhibited. 
     On the other hand, in the reciprocating compressor, in order to increase an efficiency of the compressor, the rotational shaft may be designed to be capable of operation in bi-directions. For example, a design in a manner that efficiency is high at the time of high-speed operation when rotating in a first direction and at the time of low-speed operation when rotating in a second direction which is an opposite direction of the first direction is occasionally required. However, the oil pump structure of  FIGS. 1 to 4  described above cannot be applied to the rotational shaft of the compressor designed to be bi-directionally rotatable. Therefore, when the compressor capable of the bi-directional rotation is designed as described above, even if it rotates in any direction, the pump structure capable of supplying oil is required. 
     SUMMARY 
     The present disclosure has been devised to solve the above-mentioned problems. It is an object of the present disclosure to provide a lubricant supply device that can prevent oil from leaking without reducing the diameter of a rotational shaft or enlarging the diameter of a lubricant supply device. 
     Further, it is an object of the present disclosure to provide a lubricant supply device capable of supplying oil regardless of the rotation direction, and a compressor applying such lubricant supply device. 
     Further, it is an object of the present disclosure to provide a lubricant supply device in which a slip does not occur when rotational force of the rotational shaft is transmitted to the lubricant supply device. 
     In order to solve the above described problems, in the present disclosure, there is provided a lubricant supply device  60 . The lubricant supply device  60  is installed at one end of a rotational shaft  50  provided with a hollow lubricant supply flow path  53  formed along the longitudinal direction and supplies lubricant to the lubricant supply flow path  53  and is compact, and does not occur an oil leakage phenomenon. 
     The lubricant supply device  60  includes: a fixer  61  that is provided with an oil inlet  617 , an accommodation space  615  that communicates with the oil inlet  617 , and an oil chamber  618  that is not directly communicated with the oil inlet  617  and communicates with the oil inlet  617  via the accommodation space; and a rotator  62  that is accommodated in the accommodation space  615  of the fixer  61  and is coupled to the rotational shaft  50  to rotate with the rotational shaft. 
     The oil inlet  617  may be opened downward, and the accommodation space and the oil inlet of the fixer may be installed in a state of being submerged in oil stored inside a housing of the compressor. 
     The fixer  61  includes a second fixer  612  that is provided with a through-hole  616  at the center thereof and covers an upper portion of the accommodation space. 
     The rotator  62  includes: a rotator space  625  that is provided at a position radially spaced apart from the rotational center of the rotator, and at least a part thereof faces the oil inlet  617  and the other part thereof faces the oil chamber  618 ; an inner diameter coupler  627  provided at the rotational center of the rotator; and a connector  63  that connects the inner diameter coupler  627  and the rotational shaft  50  and is provided with an oil outlet  639  connected to the oil chamber  618  and the lubricant supply flow path  53 . 
     The rotator  62  may be a form in which various parts are assembled. That is, the rotator may be a form in which the parts made of the connector and the part other than the connector are assembled and coupled. In more detail, the part other than the connector of the rotator may be a form in which two or more sub-parts are made and assembled. 
     The connector  63  includes: a rotator mounting member  632  that is inserted into and fixed to the inner diameter coupler  627 ; a penetrating member  635  that extends axially from the rotator mounting member  632  and penetrates the through-hole  616 ; a diameter extended member  633  extending radially outward from the penetrating member  635  at the upper portion of the second fixer  612 ; and a rotational shaft mounting member  631  that extends axially from the diameter enlarged member  633  and is mounted to the rotational shaft  50 . 
     The diameter of the penetrating member that penetrates a through-hole can be made smaller than the diameter of the rotator coupled to the rotational shaft by adding an enlarged diameter structure to the connector when separately making the connector. Accordingly, even if the diameter of the lubricant supply device is not increased, it is possible to make the length of the path longer, through which oil in the rotator space  625  can leak, thereby minimizing oil leakage of oil. 
     The cross sectional area inside the inner diameter coupler  627  is included in the cross sectional area inside the penetrating member  635 , or the inner diameter of the inner diameter coupler  627  is equal to or smaller than an outer diameter of the penetrating member  635 , and the outer diameter of the penetrating member  635  is smaller than the outer diameter of the rotational shaft mounting member  631  so that it is possible to prevent the oil leakage while making an assembly of the lubricant supply device convenient. 
     As the rotator  62  rotates, the oil flowed in the rotator space  625  through the oil inlet  617  is supplied to the oil chamber  618 , and the oil in the oil chamber  618  is supplied to the lubricant supply flow path  53  through the oil outlet  639 . 
     The connector  63  is made as a separate part so that the one end of the rotational shaft  50  is inserted into a shaft coupling space  637  defined by the inner diameter of the rotational shaft mounting member  631  and there is no need to increase the diameter of the first rotator  621 . In particular, this can further reduce a press-fit tolerance between the rotational shaft mounting member  631  and the outer circumferential surface  58  of the rotational shaft  50 , as compared with a structure in which a shaft coupler  626  is fitted in the inner circumferential surface of the rotational shaft  50 . 
     Further, since a processing of an outer circumferential surface  58  of the rotational shaft  50  is easier than that of an inner circumferential surface of the rotational shaft, by applying an insertion structure, it is possible to provide a first idling preventing surface (e.g., a shaft contact surface)  54  on the outer circumferential surface  58  of the one end of the rotational shaft  50  and it is possible to provide a second idling preventing surface  634  that contacts with the first idling preventing surface  54  on an inner circumferential surface  6371  of a rotational shaft mounting member  631 . 
     Further, a third idling preventing surface  628  may be provided on the inner circumferential surface  6271  of the inner diameter coupler  627  and a fourth idling preventing surface  636  that contacts with the third idling preventing surface  628  may be provided on the outer circumferential surface of the rotator mounting member  632 . 
     The fixer  61  may further include a first fixer  611  that is provided with the oil inlet  617 , the accommodation space, and the oil chamber  618  and accommodates the rotator  62 , and the second fixer  612  may cover the accommodation space in a state where the rotator  62  is accommodated in the accommodation space of the first fixer  611 . Such a fixer structure is highly convenient for assembly. 
     The rotator  62  may further include a first rotator  621  that the inner diameter coupler  627  is provided at the center thereof and includes a first tooth  623  formed radially outwards about the center of the inner diameter coupler  627 , and a second rotator  622  that is provided with a second tooth  624  formed inwards while surrounding the first tooth  623  and is accommodated in the accommodation space, and the part of the first tooth  623  and the part of the second tooth  624  are mutually engaged and the space between the first tooth  623  and the second tooth  624  may define the rotator space  625 . This not only makes a pumping structure of the lubricant, but also provides the basis that can supply the lubricant for a bi-directional rotation. 
     Particularly, the rotational center O 1  of the first rotator  621  may coincide with the rotational center O 2  of the second rotator  622  and the center C 2  of the second tooth  624  may be disposed eccentrically from the rotational center O 1  so as to make the lubricant supply device capable of being operated in the bi-directional rotation. 
     A profile of a tooth the first tooth  623  and a profile of a tooth of the second tooth  624  may include complementary shapes so as to be engaged with each other, and the number of teeth of the second tooth  624  is larger than the number of teeth of the first tooth  623  so that a rotator space  625  can be made due to the difference in the circumferential distance of a tooth. 
     The radius b of a groove of the first tooth  623  may be smaller than the radius d of a protrusion of the second tooth  624  and the radius a of a protrusion of the first tooth  623  a may be larger than the radius d of the protrusion of the second tooth  624  and smaller than the radius c of a groove. 
     The distance in which the center C 2  of the second tooth  624  is eccentric from the rotational center O 1  may be equal to or smaller than the difference between the radius c of a groove of the second tooth  624  and the radius a of the protrusion of the first tooth  623 . 
     Further, in the present disclosure, there is provided a compressor. The compressor includes: the lubricant supply device  60 ; a rotational shaft  50  installed with the lubricant supply device  60  at one end thereof; a frame  20  that includes a rotation supporter  25  that supports a rotation of the rotational shaft  50 ; the motor  21  and  52  that is provided on the rotational shaft  50  and the frame  20  and rotates the rotational shaft  50  in a first direction with regard to the frame  20  and rotates the rotational shaft  50  also in a second direction which is an opposite direction of the first direction; and a housing  10  that lubricant is stored in a lower portion and the frame  20  is accommodated in an upper portion of a lubricant storage space. 
     According to the lubricant supply device of the present disclosure, it is possible to prevent oil from leaking without reducing the diameter of the rotational shaft or increasing the diameter of the lubricant supply device. 
     Further, the lubricant supply device of the present disclosure can utilize the compressor capable of the bi-directional rotation because an oil supply using the rotational force of the rotational shaft is possible regardless of the rotation direction of the rotational shaft. Thus, it is possible to differently design an efficiency of the motor according to the rotation direction, so that a high efficiency compressor design is possible. 
     Specific effects of the present disclosure, with the above described effect, will be described in conjunction with the described specific details for implementing the present disclosure below. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a side cross sectional view of a lubricant supplier applied to a reciprocating compressor. 
         FIG. 2  is an exploded perspective view of a lubricant supplier of  FIG. 1 . 
         FIG. 3  is a cross-sectional perspective view showing an assembled state of a lubricant supplier of  FIG. 2 . 
         FIG. 4  is a cross-sectional view taken along line I-I in  FIG. 1 . 
         FIG. 5  is a side cross sectional view of a reciprocating compressor in which a lubricant supply device is installed according to an exemplary implementation of the present disclosure. 
         FIG. 6  is an enlarged view of a portion of  FIG. 5 . 
         FIG. 7  is an exploded perspective view of a lubricant supply device of  FIGS. 5 and 6 . 
         FIG. 8  is a perspective view of a connector and a first rotator of  FIG. 7  viewed from the opposite side. 
         FIG. 9  is a perspective view showing a state in which a lubricant supply device of  FIGS. 5 and 6  is installed at one end of the rotational shaft. 
         FIG. 10  is a cross sectional view taken along line II-II in  FIG. 6 . 
         FIG. 11  is a cross sectional view of another implementation of a lubricant supply device of  FIG. 10 . 
     
    
    
     DETAILED DESCRIPTION 
     Hereinafter, exemplary implementations of the present disclosure will be described in detail with reference to the accompanying drawings. 
     The present disclosure is not limited to the implementation disclosed below and may be implemented in various manners different from each other, and the implementations are provided so that this disclosure of the present disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art. 
     Referring to  FIG. 5 , a structure of a compressor to which a lubricant supply device of the present disclosure is applied is described. A compressor  1  exemplified in the present disclosure is a reciprocating compressor. 
     Each component of the compressor  1  is installed inside a housing  10 . The housing  10  includes a main housing  11  in the form of a deep container and a cover housing  12  that covers and seals an upper portion of the main housing  11 . A leg  13  is provided at the bottom of the main housing  11 . The leg  13  is configured to fix the compressor  1  to an installation position. 
     In the inner space of the housing  10 , a boss  15  is provided at the bottom. The boss  15  fixes an elastic body  16  such as a coil spring. A frame  20  is fixed to an upper portion of the elastic body  16 . The elastic body  16  fixes the frame  20  to the housing  10  while the housing  10  and the frame  20  are not directly connected. Therefore, a vibration of the frame  20  is prevented from being transmitted to the housing by the elastic body  16 . 
     A rotation supporter  25  of the frame  20  supports a rotation of a rotational shaft  50  and the rotational shaft  50  extends in the vertical direction and the rotation is supported at two points by a frame. The rotational shaft  50  of the compressor is supported at two points located at an upper portion and a lower portion of a crank pin respectively. 
     The rotational shaft  50  rotates by a motor, and the motor is controlled by an inverter. A stator  21  is fixed to the frame  20  and a rotor  52  is fixed to the rotator shaft  50  and the rotor shaft  50  rotates by inverter control. 
     The crank pin  51  is provided at the upper portion of the rotational shaft  50 . The crank pin  51  is parallel to the rotational shaft, and is disposed eccentrically from the center of the rotational shaft. 
     A cylinder  30  extending in the horizontal direction is provided at the same height in which the crank pin  51  is provided. The cylinder  30  of the compressor may be made as a separate part from the rotation supporter  25  and assembled. 
     The piston  40  may do a reciprocating motion along the longitudinal direction of a cylinder  30  regardless of the rotation direction of the rotational shaft. 
     A lubricant supplier  60  is installed at a lower portion of the rotational shaft  50 . Lubricant is stored in the lower portion of the inner space of the housing  10 . The lubricant supplier  60  is submerged in the lubricant. The lubricant supplier  60  is provided with a fixer  61  fixed to a frame  20  and a rotator  62  that rotates with a rotational shaft  50 . A relative rotation of the rotator  62  with regard to the fixer  61  pumps the lubricant upward. 
     The rotational shaft  50  is provided with a hollow lubricant supply flow path  53 . The lubricant supply flow path  53  extends from a lower end of a rotational shaft to a position near the position where lubrication is required. For example, oil (lubricant) may be supplied to a friction section of a cylinder  30  and a piston  40 , a connecting portion of a crank pin  51  and a connecting rod  46 , and a connecting portion of a connecting rod  46  and a piston  40 , and a supporting portion of a rotational shaft  50 . 
     The lubricant supplied to where it is needed flows down or falls back to the bottom of the housing  10  by gravity after wetting the corresponding portion. 
     Hereinafter, an implementation of a lubricant supply apparatus according to the present disclosure will be described with reference to  FIGS. 5 to 10 . 
     A lubricant supply device  60  includes a fixer  61  that maintains a state fixed to a frame  20  and a rotator  62  that is fixed to a lower end of a rotational shaft  50  of a compressor  1  and rotates with a rotator  62 . 
     A fixer  61  is fixed to a frame  20  of a lubricant supply device  60  through a fixed connecting member  619 . The fixer  61  remains a fixed state with a frame even if a rotational shaft  50  rotates. The fixer  61  supports a rotation of the rotator  62  and maintains a fixed state. 
     The fixer  61  includes a body portion that forms a body, that is, a first fixer  611  and a cover portion that covers an upper part of the body, that is, a second fixer  612 . 
     An accommodation space  615  that accommodates a rotator  62  is provided on an upper portion of the first fixer  611 . The accommodation space is a space defined by a side wall  613  and the bottom  614  of a first fixer  611  and is a substantially cylindrical space having small height and widely flattened. The upper portion of the accommodation space  615  is open and the lower end of a lowest portion thereof is defined by the bottom  614  of the first fixer  611 . The upper portion of the accommodation space  615  is covered by a second fixer  612 . 
     The second fixer  612  is coupled to the first fixer  611  in a form of covering and surrounding the upper portion of the accommodation space  615  and the outer circumferential surface of the side wall  613 . As a specific method of coupling the first fixer  611  and the second fixer  612 , a ring-shaped first mounting member  64  that has a fitting hole opened laterally is provided on the side of the second fixer  612 , and a second mounting member  65  in the form of an engaging hook capable of being fitted to the fitting hole is provided on the side of the first fixer  611 . The second mounting member  65  has a shape gradually protruding as it is closer downward. A first mounting member  64  extends further downward than a side wall of the first fixer  611 , so that it is easily deformed. The first mounting member  64  is elastically deformed in contact with the upper portion of the second mounting member  65 . When the second mounting member  64  contacts with a hole of the first mounting member  64 , the first mounting member may be elastically deformed and a ring-shaped lower end of the first mounting member  64  is engaged with a lower portion of the second mounting member. 
     A circular through-hole  616  is provided at the center of the second fixer  612 . A connector  63  of a rotator  62  to be described later penetrates through the through-hole  616 . 
     The bottom  614  is provided with the oil inlet  617  that penetrates vertically in order to communicate an outer space in the lower portion of the first fixer  611  with the accommodation space  615  and an oil chamber  618  formed as a part of the surface facing the accommodation space  615  is depressed at a position that is not overlapped with a position where the oil inlet  617  is formed. 
     The oil inlet  617  is a form that penetrates the bottom  614  vertically. Therefore, through the oil inlet  617 , the accommodation space  615  and the space in the lower portion of the bottom  614  of the first fixer  611  are connected to each other. 
     The first distance to the position in which the oil inlet  617  is formed from the center of the bottom  614  to the radial direction is the same as the second distance to the position in which the oil chamber  618  is formed from the center of the bottom  614  to the radial direction. The oil chamber  618  has a form extending radially to the center of the bottom  614 . The first fixer  611  is almost submerged in oil. For reference, line II-II of  FIGS. 5 and 6  is a reference line that shows a cross section of  FIGS. 10 and 11  and indicates oil level of lubricant stored in the bottom of a housing  10  approximately. Therefore, the lubricant stored in the housing can be flowed in the accommodation space  615  through the oil inlet  617 . 
     The oil chamber  618  is a groove formed in an upper surface of the bottom. That is, the oil chamber  618  is a space that is depressed more than an upper surface of the bottom  614 . The bottom surface of the oil chamber  618  is closed  7 . Thus, even if the first fixer  611  is submerged in oil as  FIG. 7 , the oil outside the first fixer  611  can be flowed in the oil chamber  618  only through the oil inlet  617 . 
     Referring to  FIGS. 10 and 11 , the oil inlet  617  penetrates through an arc-shaped cross section at a position deviated from the center of the first fixer  611 . The oil chamber  618  has an arc-shaped form within a range not overlapping with the oil inlet  617  and is a groove shape including the center of the first fixer  611 . The oil chamber  618  may be similar to a substantial “T” shape. 
     A first rotator  621  and a second rotator  622  are accommodated in an accommodation space  615 . The first rotator  621  is accommodated inside the second rotator  622 . That is, the second rotator  622  is arranged in a form of surrounding the perimeter of the first rotator  621 . A plurality of first teeth  623  are continuously provided along the circumferential direction on an outer circumferential surface of the first rotator  621  and a plurality of second teeth  624  are continuously provided along the circumferential direction on an inner circumferential surface of the second rotator  622  that faces the outer circumferential surface of the first rotator  621 . A few first teeth  623  are engaged with a few second teeth  624 . Accordingly, when the first rotator  621  rotates, the second rotator which is engaged with the first rotator  621  also rotates together. 
     The first rotator  621  is connected to a lower end, that is, one end of the rotational shaft  50  through the second fixer  612  by a connector  63 . The connector  63  is a separate part from the first rotator  621 . The connector  63  is connected to the first rotator  621  so as to rotate together with and is connected to the rotational shaft  50  so as to rotate together with. Therefore, when the rotational shaft  50  rotates, it is integrally rotated with the connector  63  and the first rotator  621 , and a second rotator  622  rotates by being interlocked therewith. 
     The center of the first rotator  621  is provided with a hole-shaped inner diameter coupler  627  penetrated vertically. The inner diameter coupler  627  has a third idling preventing surface  628  in the form of a D cut form as shown in  FIG. 8 . 
     The diameter of the inner diameter coupler  627  may be smaller than or equal to the diameter of a through-hole  616  of the second fixer  612 . The cross-sectional area of the inner diameter coupler  627  is included in the cross-sectional area of the through-hole  616  of the second fixer  612 . Accordingly, when viewed from the upper portion of  FIG. 7 , it is possible to see the entire inner diameter coupler  627  through the through-hole  616 . That is, the entire inner diameter coupler  627  is exposed to an upper portion through the through-hole  616 . 
     The connector  63  is coupled from the upper portion of the through-hole  616  to the inner diameter coupler  627  through the through-hole  616 . The connector  63  includes a rotator mounting member  632  that is inserted into or press-fitted to the inner diameter coupler  627  through the through-hole  616  and a penetrating member  635  in which the outer circumferential surface thereof faces an inner circumferential surface of the through-hole  616  in a state where it extends to an upper portion of the rotator mounting member  632  and penetrates the through-hole  616 , an diameter enlarged member  633  that extends radially outwards along an upper surface of the second fixer  612  at the upper portion of the penetrating member  635 , and a rotational shaft mounting member  631  in a cylinder form that extends upwards from radial end of the diameter enlarged member  633 . 
     An oil outlet  639  opened vertically is provided at the center of the rotator mounting member  632 , the penetrating member  635 , the diameter enlarged member  633  and the rotational shaft mounting member  631 . The oil outlet  639  communicates with a portion of an oil chamber  618  disposed at the center of the first fixer  611  downwardly and communicates with a lubricant supply flow path  53  formed inside the rotational shaft  50  upwardly. 
     The rotator mounting member  632  includes an outer circumferential surface  6322  that has the outer diameter corresponding to the inner diameter coupler  627  and has a D cut shape having a fourth idling preventing surface (e.g., an outer contact portion)  636  corresponding to the third idling preventing surface (e.g., a coupler contact surface)  628 . Thus, the rotator mounting member  632  can be fitted to the inner diameter coupler  627  of the first rotator  621  through the through-hole  616  of the second fixer  612  from the upper portion, and can be rotated in the rotation direction without a slip phenomenon with the second fixer  612 . 
     The penetrating member  635  includes an outer circumferential surface having a circular profile facing an inner circumferential surface of the through-hole  616 . The inner circumferential surface of the through-hole  616  and the outer circumferential surface of the penetrating member  635  are the surfaces that a relative rotation is made to each other and the surfaces in order for oil inside an accommodation space  615  not to leak, and it has a narrow clearance suitable for it. 
     The diameter enlarged member  633  is a member that increases the diameter of a portion of a connector  63  disposed at an upper portion of a second fixer  612 . A lower surface of the diameter enlarged member  633  may face an upper surface of the second fixer  612  and can guide a relative rotation therebetween. 
     The diameter of the rotational shaft mounting member  631  extending upward from the diameter enlarged member  633  is set larger than that of the through-hole  616 . The rotational shaft mounting member  631  may be inserted inside the rotational shaft  50  similarly to a prior structure, but it is possible to be inserted outside the rotational shaft  50  (see  FIGS. 6 and 9 ), that is, rotational shaft  50  is inserted inside the rotational shaft mounting member  631 . When the rotational shaft mounting member  631  is inserted outside the rotational shaft  50 , it is advantageous in many points than being inserted therein. 
     A first idling preventing surface  54  in the form of a D cut is provided on an outer circumferential surface of a lower end of the rotational shaft  50  and a second idling preventing surface  54  in the form of a D cut corresponding to the first idling preventing surface  54  is formed on an inner circumferential surface of the rotational shaft mounting member  631 . Thus, the rotational shaft mounting member  631  inserted outside the lower portion of the rotational shaft  50  may rotate integrally with the rotational shaft without a slip phenomenon. 
     If the shaft coupler  626  is inserted inside a lubricant supply flow path  53  of the rotational shaft  50 , it is difficult to apply a D cut structure. It is necessary to perform a drilling processing for providing the lubricant supply flow path  53  along the longitudinal direction of the rotational shaft  50 . But it is difficult to make the D cut structure while drilling the inner circumferential surface. Further, an outer circumferential surface of a prior shaft coupler  626  and an inner circumferential surface of a lubricant supply flow path  53  were difficult to lower the press-fit tolerance to 0.2 mm or less due to the processing method. This may cause a problem that the shaft coupler  626  and the rotational shaft  50  do not rotate integrally and the slip phenomenon occurs. 
     On the other hand, when a structure in which the rotational shaft mounting member  631  is inserted outside the outer circumferential surface of the rotational shaft  50  is applied as described in the present disclosure, it is easy to make the D cut structure and it is possible to adjust the press-fit tolerance to 0.103 mm or less. Therefore, the connector  63  and the rotational shaft  50  can be press-fitted to each other accurately and an integral rotation in which the slip does not occur is possible. 
     Further, as described above, when a structure in which the first rotator  621  and the connector  63  are made as a separate part and mounted is adopted, as compared with a prior structure ( FIGS. 1 to 3 ), it is possible to set the size of the through-hole  616  to be much smaller than the cross sectional area of the lubricant supply flow path  53 . Thus, since it is possible to set the distance d 1  between the outer circumferential surface of the first rotator  621  and the inner circumferential surface of the through-hole  616  to be large, a phenomenon in which the oil in the rotator space  625  adjacent to the outer circumferential surface of the first rotator  621  leaks to the inner circumferential surface of the through-hole  616  can be minimized. 
     Further, unlike the prior structure ( FIGS. 1 to 3 ) in which the diameter of the shaft coupler  626  cannot be varied vertically for the assembly with the second fixer  612 , according to the present disclosure, since it is possible to make the diameter of the inner circumferential surface of the rotator mounting member  632  smaller than that of the inner circumferential surface of the rotational shaft mounting member  631 , it is possible to increase the distance d 2  of the inner circumferential surface of the oil outlet  639  and the oil inlet  617  so that the oil does not leak. 
     Since it is not required to increase the sizes of the first rotator or the second rotator in securing the distances d 1  and d 2 , it is possible to make the lubricant supply device compact, and it is possible to minimize the power consumption of the rotational shaft in driving the rotator of the lubricant supply device. 
     When a rotational shaft  50  rotates, a connector  63  and a first rotator  621  rotate together. A second rotator  622  installed to receive a rotational force with regard to the first rotator  621  also rotates. 
     An outer circumferential surface of the second rotator  622  accommodated in the accommodation space  615  faces an inner circumferential surface of a side wall  613  of the first fixer  611  and a rotation of the second rotator  622  is guided by the inner circumferential surface of a side wall  613 . 
     The first rotator  621  and the second rotator  622  accommodated in the accommodation space  615  is supported by an upper surface of the bottom  614  of the first fixer  611 , and is supported by a lower surface of the second fixer  612 . 
     As such, the second rotator  622  is installed in a fixer  61  so as to be rotatable about a rotational center O 2  thereof. 
     The first rotator  621  is also rotatably installed in the fixer  61 . Since the first rotator  621  rotates with the rotational shaft  50 , the rotational center O 1  of the first rotator  621  coincides with the rotational center of the rotational shaft  50 . 
     An oil outlet  639  penetrating vertically is formed inside a connector  63  which is axially coupled to the first rotator  621 . The oil outlet  639  communicates with a lubricant supply flow path  53  of the rotational shaft  50  upward and communicates with the oil chamber  618  downward. The lubricant supply flow path  53  is not overlapped with an oil inlet  617 . Thus, oil outside a first fixer  611  may be supplied to a lubricant supply flow path  53  sequentially through an oil inlet  617 , an accommodation space  615 , an oil chamber  618 , and an oil outlet  639 . 
     The first rotator  621  and the second rotator  622  rotate in a state of being accommodated in the accommodation space  615 . 
       FIG. 10  shows a lubricant supply device capable of supplying lubricant when a rotator rotates clockwise. 
     The rotational center O 1  of a first rotator  621  coincides with the rotational center of a rotational shaft  50 . A first tooth  623  in an outwardly protruding shape is formed on an outer circumferential portion accommodated in the accommodation space in the first rotator  621 . The center C 1  of the first teeth  623  provided on an outer circumferential surface of the first rotator  621  coincides with the rotational center O 1  of the first rotator  621 . In other words, a plurality of first teeth  623  is formed radially with regard to the rotational center of the first rotator  621 . Accordingly, the first tooth  623  rotates about the rotational center O 1  of the first rotator. In the implementation, a structure in which seven first teeth  623  are provided will be illustrated. 
     The rotational center O 2  of the second rotator  622  is offset in a position eccentric from the rotational center O 1  of the first rotator  621  and arranged. A second tooth  624  in an inwardly protruding shape is formed on the inner diameter of the second rotator  622  that surrounds the first rotator  621 . A plurality of second teeth  624  is formed radially with regard to the center C 2  thereof. The number of second teeth is larger than the number of first teeth. As one example, a structure in which eight second teeth  624  are provided may be illustrated. The center C 2  of the second teeth  624  provided on the inner circumferential surface of the second rotator  622  coincides with the rotational center O 2  of the second rotator  622 . Accordingly, the second tooth  624  rotates about the rotational center O 2  of the second rotator. 
     Two teeth  623  and  624  may be made of a shape corresponding to each other and can be tooth-engaged. The profile of the teeth may be a trocoide shape. 
     When the first rotator  621  rotates as the rotational shaft  50  rotates, rotational force of the first rotator  621  is transmitted to the second rotator  622  through the first tooth  623  and the second tooth  624 . 
     The first tooth and the second tooth are engaged along the circumferential direction in a certain section part but are not engaged in the other section part. In other words, in a section indicated by a substantial G shape in  FIG. 10 , the first tooth is engaged with the second tooth to transmit the rotational force of the first rotator to the second rotator, and they are not engaged with each other or incompletely engaged in a section other than the above to form a rotator space  625 . 
     Since the center C 2  of the second tooth  624  coincides with the center O 2  of the second rotator  622 , the second tooth  624  rotates in place while pivoting about the center of the rotator  621 . That is, the first tooth  623  rotates about its center C 1  and the second tooth  624  also rotates about its center C 2 . 
     Therefore, the rotator space  625  also maintains its position without rotation. When a rotator  62  rotates clockwise, the rotator space  625  is gradually narrowed from an oil inlet  617  toward an oil chamber  618  while two teeth  623  and  624  rotate. 
     Therefore, oil that is trapped in the rotator space  625  and moves with the tooth is pressurized by a gradually narrowing space to be pushed into the oil chamber  618 , and the oil pushed into the oil chamber  618  moves upwards through an oil outlet  639 . 
     According to such a structure, since the oil trapped in the gradually narrowing space is extruded and supplied, a supply of the lubricant may be made very well. On the other hand, in  FIG. 10 , when the rotator  62  rotates counterclockwise, an oil supply is not made. 
     On the other hand, a structure and an operation of the lubricant supply device in which the oil supply can be made even when rotating clockwise as well as counterclockwise will be described with reference to  FIG. 11 . 
     Referring to  FIG. 11 , the rotational center O 1  of the first rotator  621  and the rotational center O 2  of the second rotator  622  coincide with each other. 
     A first tooth  623  in an outwardly protruding shape is formed at an outer diameter portion of the first rotator  621  accommodated in the accommodation space. A plurality of first teeth  623  is formed radially about the rotational center of the first rotator  621 . Accordingly, the first tooth  623  rotates about the rotational center O 1  of the first rotator. As one example, a structure in which seven first teeth  623  is provided will be illustrated. 
     A second tooth  624  in the inwardly protruding shape is formed on the inner diameter portion of the second rotator  622  surrounding the first rotator  621 . A plurality of second teeth  624  may be formed radially with regard to the center C 2  thereof. The number of second teeth may be larger than that of the first teeth. As one example, a structure in which eight second teeth  624  are provided will be illustrated. 
     Two teeth  623  and  624  have a shape corresponding to each other and can be tooth-engaged with each other. The profile of the teeth may be a trocoide shape. 
     The radius b of a groove of the first tooth  623  is smaller than the radius d of a protrusion of the second tooth  624 . Further, the radius a of a protrusion of the first tooth  623  is larger than the radius d of the protrusion of the second tooth  624  and smaller than the radius c of a groove of the second tooth  624 . 
     According to another implementation of the present disclosure shown in  FIG. 11 , the center C 2  of the second tooth  624  is eccentric with regard to the center O 2  of the second rotator  622 . The eccentric distance is equal to or slightly smaller than the difference between the radius c of a protrusion of the second tooth  624  and the radius a of the protrusion of the first tooth  623 . Therefore, a rotator space  625  exists between the first tooth  623  and the second tooth  624 . 
     The volume of the rotator space  625  is distributed more in adjacent to the center C 2  of the second tooth with regard to the rotational centers O 1  and O 2 . Conversely, the first tooth  623  and the second tooth  624  are mutually engaged on the side far from the center C 2  of the second tooth based on the rotational centers O 1  and O 2 . 
     Since two rotational centers O 1  and O 2  coincide with each other, when a rotational shaft  50  rotates, the first rotator  621  and the second rotator  622  concentrically rotate together. However, since the center C 2  of the second tooth  624  is eccentric from the center O 2  of the second rotator  622 , the center C 2  of the second tooth  624  is revolved about the rotational center O 2  of the second rotator  622 . Thus, the rotator space  625  is also revolved about the rotational center O 2  of the second rotator  622 . 
     According to such a rotation motion, the first rotator  621  and the second rotator  622  rotate at the same angular velocity to each other while a position in which the first tooth  623  and the second tooth  624  are not engaged with each other is not changed. This is distinguished from the fact that the angular velocity of the first rotator  621  is faster than that of the second rotator  622  in the implementation of  FIG. 10 . 
     An oil inlet  617  of a first fixer  611  is in a position overlapped with a revolving orbit of the rotator space  625 . Thus, when a rotator  62  rotates in a state in which the oil inlet  617  and the rotator space  625  are overlapped with each other, the oil that has flowed in the rotator space  625  through the oil inlet  617  revolves together in a state of being tapped in the rotator space  625 . 
     The oil chamber  618  is also in a position being overlapped with a revolving orbit of the rotator space  625 . Therefore, the oil moved through the accommodation space  615  in a state of being trapped in the rotator space  625  falls to the oil chamber  618  by gravity. The oil falling in the oil chamber  618  has a linear velocity of the rotator space  625  and is forcedly flowed in the oil chamber  618  so that oil filled in the oil chamber  618  is pushed up and go up to an upper portion through an oil outlet  629 . 
     In  FIG. 11 , a form in which a rotator  62  rotates clockwise is shown as an arrow. However, according to the above-described principle, even if the rotator  62  rotates counterclockwise, a lubricant supply action occurs to the same extent as rotating clockwise. Therefore, a lubricant supply device according to the present disclosure shown in  FIG. 11  can supply lubricant regardless of a rotation direction of a rotational shaft. 
     When the lubricant supply device of the present disclosure is applied to a reciprocating compressor, both a compression operation and a lubricant supply operation are made well even if the rotational shaft  50  rotates in any direction. Therefore, the maximum efficiency speed range when a motor rotates in the forward direction and rotates in the reverse direction can be designed differently, so that an efficiency of a compressor can be increased at a wider operation speed of a compressor. 
       FIG. 9  shows that a lubricant supply flow path  53  is formed on a rotational shaft  50 , which is expected to rotate in the bi-direction. The lubricant supply flow path  53  is provided at a lower portion of the rotational shaft  50  at an inner diameter portion, which is branched and extends upward. That is, a part of the flow path  53  extends through an inner portion of the rotational shaft  50  as shown in  FIG. 5 , and the part of the flow path  53  extends in a groove at an outer diameter portion of the rotational shaft  50 . 
     In  FIG. 9 , a groove-shaped lubricant supply flow path  53  formed in an outer diameter of the rotational shaft  50  or a crank pin  51  is formed in a linear shape which is a direction parallel to the longitudinal direction of a rotational shaft. This is a structure that allows oil to move upwards even if it rotates in any direction. 
     According to the implementation of  FIG. 11 , a structure, in which the rotator  62  is divided into a first rotator and a second rotator and the divided first rotator and second rotator are mounted, is illustrated. However, according to the present disclosure, it is possible to manufacture the rotator  62  as a single part, and form a rotator space  625  at a position radially spaced part from the rotational center and expect the same operation even if a revolving orbit of the rotator space  625 , the oil inlet  617 , and the oil chamber  618  are overlapped. 
     However, the above-described implementation is more advantageous in that a common use of a part with a lubricant supply device of  FIG. 10  in which a lubricant can be supplied at the time of a uni-directional rotation. 
     The geometrical difference between  FIGS. 10 and 11  is only the positional difference of the rotational center O 2  of the second rotator  622 . Due to this position change of the center O 2 , the lubricant supply device may be a uni-directional supply device or a bi-directional supply device. 
     Therefore, when the above configuration is included, the common use of the part of the uni-directional supply device and the bi-directional supply device of the lubricant is possible. For example, the components of a first fixer and a second rotator of two supplying devices are different from each other, and the components of a second fixer and a first rotator can be commonly used. 
     While the present disclosure has been described with reference to the exemplary drawings thereof, the present disclosure is not limited to the disclosed exemplary implementations and drawings disclosed in the present specification, it will be apparent to one skilled in the art in the scope of the technical spirit of the present disclosure that various modifications can be made. In addition, although the working effects provided by a certain configuration of the present disclosure are not clearly described in description of the exemplary implementation of the present disclosure, it should be noted that expectable effects of the corresponding configuration should be acknowledged.