WO2009078676A1

WO2009078676A1 - Hinge assembly for home bar door of refrigerator and refrigerator using the same

Info

Publication number: WO2009078676A1
Application number: PCT/KR2008/007504
Authority: WO
Inventors: Myung Hoon Choi
Original assignee: Dong Woo.Inc
Priority date: 2007-12-18
Filing date: 2008-12-18
Publication date: 2009-06-25
Also published as: KR100875475B1

Abstract

Disclosed is a hinge assembly for rotatably setting a home bar door onto a refrigerator door, and a refrigerator using the same. The hinge assembly includes a hinge axis extended from a home bar door opening/closing an opening in a refrigerator door; and an oil damper including a housing fixed onto the refrigerator door, a rotary shaft inserted into the housing to form a sealed space filled with oil, and connected to the hinge axis to attenuate rotation force of the hinge axis by forming a blade on one side to move in the oil, a penetration opening formed through the rotary shaft and connect the sealed space with exterior, and a fixing member inserted to/fixed to the penetration opening to seal the penetration opening. According to an embodiment, a refrigerator includes a body with a food preservation chamber kept at low temperature, a refrigerator door formed in the body to open/close the food preservation chamber and having an opening penetrating therethrough, a home bar door disposed to open/close the opening and having a hinge axis protruded from a lower part, and the hinge assembly.

Description

HINGE ASSEMBLY FOR HOME BAR DOOR OF REFRIGERATOR AND REFRIGERATOR USING THE SAME

Technical Field

[1] The present invention relates to a refrigerator; and, more particularly, to a hinge assembly for a home bar door of a refrigerator door, which is rotatably set up in a refrigerator door for opening/closing a food preservation chamber of the refrigerator. Background Art

[2] A refrigerator is a food container for keeping food fresh for a long time by maintaining the food container at a low temperature based on a freezing cycle. Cooling air supplied to the food preservation chamber may leak out of the wall of the refrigerator but a considerable amount of it leaks out every time when the door of the refrigerator is open. The leakage amount of the cooling air following an opening of the refrigerator door not only increases power consumption but also widens the fluctuation of the temperature in the food preservation chamber to thereby degrade the freshness of the food kept inside and shorten the preservation time of the food. In an attempt to resolve such a problem, refrigerators with a home bar door in the refrigerator door are popularized recently.

[3] The home bar door is a small door connected to a refrigerator door with a hinge to open/close an opening formed through the refrigerator door. Generally, the home bar door has both sides of its lower part connected to the refrigerator door with hinges, and it is open/closed by rotating in an up and down direction. When the home bar door is completely open, it is laid almost horizontally and serves as a small table on which a drink bottle can be put. A small food preservation space for containing beverages and drinking water that a person frequently withdraw is provided in the inside of the opening, and the user can open and withdraw the beverages and drinking water arranged in the housing space. With the home bar door, the number of opening the refrigerator door is reduced to thereby not only reduce the power consumption but also improve the convenience on the part of the user.

Disclosure of Invention

Technical Problem

[4] An embodiment of the present invention is directed to a home bar door formed to be open/closed by rotating in an up and down direction around the hinge at the lower part. When the home bar door is pulled out, the home bar door is open by drastically rotating around the hinge by its own weight. When the home bar door is maximally open, the hinge receives an impact. Accordingly, in the long term, the hinge of home bar door is damaged. Technical Solution

[5] In accordance with an aspect of the present invention, there is provided a hinge assembly for a home bar door of a refrigerator, including: a hinge axis extended from a home bar door for opening/closing an opening formed in a refrigerator door; and an oil damper including a housing fixed onto the refrigerator door, a rotary shaft inserted into the housing to thereby form a sealed space to be filled with oil, and connected to the hinge axis to attenuate a rotation force of the hinge axis by forming a blade on one side to move in the oil when the hinge axis rotates, a penetration opening formed to penetrate the rotary shaft and connect the sealed space with an exterior, and a fixing member inserted to and fixed to the penetration opening to seal the penetration opening.

[6] The rotary shaft may include: a partition unit tightly contacting an inner surface of an accommodation space formed inside the housing to thereby form the sealed space; a damping unit provided with more than one blade disposed to be submerged in the oil of the sealed space and a fluid channel formed to penetrate at least any one of the blades; and driving unit connected to the hinge axis and rotating together with the blades.

[7] The radius of a cross section of the sealed space may change according to a rotation direction of the blades.

[8] The gap between the inner wall of the sealed space and ends of the blades may decrease gradually as the blades rotate in one direction.

[9] The fluid channel may be formed at the bottom of the blades contacting the bottom of the housing.

[10] The hinge assembly may further include: a first opening formed in a lower part of the damping unit contacting the bottom of the housing and connecting the penetration opening with the sealed space.

[11] The hinge assembly may further include: a second opening formed in an upper part of the damping unit and connecting the penetration opening with the sealed space.

[12] The blades may be provided in a pair, and the blades are disposed in opposite to each other in the sealed space.

[13] The hinge assembly may further include: a stopper protruded from the inner surface of the housing toward the inside of the sealed space and limiting a rotation angle of the rotary shaft.

[14] The stopper may be disposed to contact an external surface of the rotary shaft and partitions the sealed space together with the rotary shaft.

[15] In accordance with an aspect of the present invention, there is provided a refrigerator, including: a body with a food preservation chamber kept at a low temperature inside; a refrigerator door formed in the body to open/close the food preservation chamber and having an opening formed penetrating therethrough; a home bar door disposed to open/ close the opening and having a hinge axis protruded from a lower part; and an oil damper comprising: a housing fixed to the refrigerator door; a rotary shaft inserted to the housing to thereby form a sealed space filled with oil and connected to the hinge axis in such a manner that when the rotary shaft rotates, a blade formed in one side moves in the oil to attenuate a rotation force of the hinge axis; a penetration opening formed to penetrate the rotary shaft and connecting the sealed space with an exterior; and a fixing member inserted to and fixed to the penetration opening and sealing the penetration opening.

Advantageous Effects

[16] The home bar door of the present invention is mounted on a refrigerator door by a hinge assembly, which includes a hinge axis and an oil damper. The oil damper attenuates a drastic rotation and impact that may be caused by the home bar door when the home bar door is open/closed. The technology of the present invention can prevent not only a sudden opening of the home bar door but also damage of the hinge by an excessive impact when the home bar door is open.

[17] According to the present invention, since the structure of a rotary shaft rotating in a housing is optimized, the structure of the oil damper is simplified and the number of parts is reduced. Therefore, productivity improves.

[18] In the oil damper constituting the hinge assembly of the present invention, viscose fluid, e.g., oil, is injected through a penetration opening formed to penetrate the rotary shaft, and the penetration opening is sealed up by a fixing member after the oil injection. The penetration opening is connected to a sealed space accommodating the oil through a small opening. This structure can effectively prevent the viscose fluid from leaking out of the oil damper. Therefore, the technology of the present invention can not only protect the device from getting dirty by leaked oil but also maintain a stable attenuation capability when the device is used quite long.

[19] A cross section of the sealed space in the housing filled with the viscose fluid changes according to a rotation direction of the blade in the oil damper constituting the hinge assembly. This structure changes the attenuation force of the oil damper according to the extent of rotation of the blade. Since the home bar door is designed to produce little attenuation force during the initial period of the opening of the home bar door and then to gradually increase the attenuation force as the home bar door gets open, the convenience on the part of a user can be improved.

[20] In the oil damper constituting the hinge assembly of the present invention, the blade and a fluid channel are designed symmetrically. This structure prevents the attenuation force from being concentrated on a specific part in the sealed space filled with the viscose fluid, and thus the oil damper can be designed to be structurally stable. Brief Description of Drawings

[21] Fig. 1 is a front view illustrating a refrigerator in accordance with an embodiment of the present invention.

[22] Fig. 2 is an exploded perspective view briefly describing a home bar door and a hinge assembly of the refrigerator shown in Fig. 1.

[23] Fig. 3 is an exploded perspective view illustrating a rotation-type oil damper of a hinge assembly shown in Fig. 2.

[24] Fig. 4 is a perspective view showing a rotary shaft of the rotation-type oil damper shown in Fig. 3.

[25] Fig. 5 is a perspective view showing a cross section of the rotation-type oil damper of

Fig. 2 taken along an I-I line.

[26] Fig. 6 is a perspective view showing a cross section of the rotation-type oil damper of

Fig. 2 taken along a II-II line.

[27] Figs. 7 and 8 are cross sections sequentially showing a rotation of a rotary shaft.

Best Mode for Carrying out the Invention

[28] The advantages, features and aspects of the invention will become apparent from the following description of the embodiments with reference to the accompanying drawings, which is set forth hereinafter. The same name and reference numerals are given to the same constituent elements although they appear in different drawings, and description on them will not be provided additionally.

[29] Fig. 1 is a front view illustrating a refrigerator in accordance with an embodiment of the present invention. As illustrated in Fig. 1, the refrigerator includes a body 10 with a food preservation chamber (not shown), a refrigerator door 11 set up in the body 10, and a home bar door 15 set up in a refrigerator door 11 by a hinge assembly.

[30] Although not illustrated, the body 10 includes typical constituent elements such as a compressor, a condenser, an evaporator, and a cooling pipe connecting the compressor, the condenser and evaporator, which constitute a cooling cycle, and a refrigerant filling the cooling pipe and circulating. The refrigerant absorbs heat from the surroundings as it evaporates in an evaporator, and the air around the evaporator whose temperature is lowered is supplied to the food preservation chamber (not shown). The food preserved in the food preservation chamber is kept fresh for a long time in a frozen or cold state.

[31] The body 10 may include one food preservation chamber or two food preservation chambers, which are a freezing chamber and a refrigeration chamber. The refrigerator shown in Fig. 1 illustrates an embodiment of the latter. The body 10 includes two re- frigerator doors 11 for opening/closing each food preservation chamber. Any of the refrigerator doors 11 includes a dispenser 12, as illustrated in Fig. 1 as an example, and the other includes a home bar door 15.

[32] The dispenser 12 supplies a user with ice produced in a freezer without its refrigerator door 11 open. When the dispenser 12 is provided with a water outlet, the user can acquire cold water or hot water from the dispenser 12. As general refrigerators are adopting the dispenser 12, detailed description on their structure will not be provided herein.

[33] The refrigerator door 11 includes an opening 13 illustrated in Fig. 1, the opening 13 is formed penetrating the refrigerator door 11 to connect the food preservation chamber and the outside. The inner part of the refrigerator door 11 may be provided with a rack for a home bar purpose (not shown), and the user can house frequently withdrawn food, beverages, and/or drinking water. The user can withdraw the food, beverages, and/or drinking water housed in the home bar rack out of the opening 13 without opening the refrigerator door 11.

[34] The home bar door 15 is set up in the refrigerator door 11 to be rotatable and opens/ closes the opening 13. The home bar door 15 is set up in the refrigerator door 11 by a hinge assembly fabricated according to an embodiment of the present invention. Hereafter, a structure of the hinge assembly will be described with reference to Figs. 2 to 5.

[35] Fig. 2 is an exploded perspective view briefly describing a home bar door and a hinge assembly of the refrigerator shown in Fig. 1. Fig. 3 is an exploded perspective view illustrating a rotation-type oil damper of a hinge assembly shown in Fig. 2. Fig. 4 is a perspective view showing a rotary shaft of the rotation-type oil damper shown in Fig. 3. Fig. 5 is a perspective view showing a cross section of the rotation-type oil damper of Fig. 2 taken along an I-I line.

[36] Referring to Fig. 2, the hinge assembly of the embodiment of the present invention includes a hinge axis 16 extended from the home bar door 15 and a rotation-type oil damper 100 set up in the refrigerator door 11 and connected to the hinge axis 16.

[37] The hinge axis 16 may be protruded from the sides of the lower part of the home bar door 15, as illustrated in Fig. 2. The hinge axis 16 may be disposed on both sides of the home bar door 15. Any one of them may be connected to the oil damper 100, and the other may be set up in the refrigerator door 11 to be rotatable. It is also possible to form two oil dampers 100 to be connected to hinge axes 16 on both sides of the home bar door 15.

[38] A connection protrusion 17 may be formed at an end of the hinge axis 16 connected to the oil damper 100. The connection protrusion 17 is engaged with a rotary shaft 130 of the oil damper 100, which will be described later, so that the hinge axis 16 rotates along with the rotary shaft 130 without skidding.

[39] The oil damper 100 is set up in the refrigerator door 11 and connected to the hinge axis 16 so as to attenuate a drastic increase in the rotation force of the hinge axis 16 caused by the weight of the home bar door 15 when the home bar door 15 is open/ closed. Accordingly, it is possible to effectively protect the hinge axis 16 from being impacted when the home bar door 15 is open suddenly and completely.

[40] Referring to Figs. 3 and 5, the oil damper 100 includes a housing 110, a cover 120 connected to the upper part of the housing 110, and a rotary shaft 130 formed in an accommodation space of the housing 110.

[41] The housing 110 includes the accommodation space into which the rotary shaft 130 is inserted. In the embodiment of the present invention, the housing 110 has a cylindrical accommodation space.

[42] The housing 110 may be set up and fixed in the refrigerator door 11, which is a setup target, in diverse methods. For example, the housing 110 may be inserted into the setup target to be fixed, or as illustrated in Figs. 2 and 3, a connection portion 111 with a fastening opening 11 Ia to be connected with an external apparatus in the exterior of the housing 110 is formed so that the housing 110 can be stably fixed to the refrigerator door 11, which is the setup target, by a fastening member (not shown).

[43] The cover 120 is connected to the upper part of the housing 110. As illustrated in Fig.

3, a fastening member 126 is inserted to a fastening hole 124 formed in an edge of the cover 120 to be connected to the connection opening 114 of the housing 110.

[44] Meanwhile, the cover 120 has a cover opening 122 at the center to structurally connect the rotary shaft 130 inserted into the inside of the housing 110 with an external device. The rotary shaft 130 is provided in the accommodation space formed inside the housing 110 to be rotatable, and it is structurally connected to the external device through the cover opening 122 formed in the cover 120.

[45] The rotary shaft 130 is inserted to the housing 110 to thereby form a sealed space (A) filled with oil. When the rotary shaft 130 is connected to the hinge axis 16 and rotates, a blade 152 formed in one side moves in the oil filling the sealed space (A) so as to attenuate the rotation force of the hinge axis 16. The rotary shaft 130 may include a partition unit 140, a damping unit 150, and a driving unit 160, as illustrated in Fig. 3.

[46] The partition unit 140 has a form corresponding to the side surface of the accommodation space to be brought into a tight contact with the inner surface of the accommodation space so as to partition the accommodation space into upper and lower parts. Accordingly, a sealed space (A) surrounded by the partition unit 140 and the housing 110 is formed in the lower part of the partition unit 140. Herein, the sealed space (A) is filled with viscose fluid, e.g., oil.

[47] To improve the airtightness between the partition unit 140 and the side surface of the accommodation space, a ring-type sealing member 172 is inserted to the external surface of the partition unit 140. Meanwhile, a sealing groove 142 to be engaged with the sealing member 172 is formed in the partition unit 140.

[48] The damping unit 150 includes a plurality of blades 152 disposed in the lower part of the partition unit 140 to submerge in the oil of the sealed space (A). As shown in Fig. 6, the blades 152 are disposed to contact the internal walls of the sealed space (A) and thus partition the sealed space (A) into a plurality of unit spaces.

[49] In the embodiment of the present invention, a pair of blades 152 is disposed in opposite to each other, which is illustrated in Fig. 4. Disposing the blades 152 symmetrically can prevent the attenuation force from being concentrated on a specific part and thus acquire a structural stability.

[50] At least one of the blades 152 may have a fluid channel 154 formed to penetrate the blade 152 and connect the segments of the separated sealed space (A). In the embodiment of the present invention, the fluid channel 154 is formed in each of the blades 152, as illustrated in Fig. 4. The fluid channel 154 is formed in the shape of an arc at the bottom of the blades 152, which contacts the bottom of the housing 110 so that viscose fluid could pass through the fluid channel 154 while the damping unit 150 contacts the housing 110.

[51] Meanwhile, viscose fluid filling the sealed space (A) flows through the fluid channel

154 and attenuation force is acquired by resistance force produced by the flowing of the viscose fluid through the fluid channel 154.

[52] The rotary shaft 130 has a penetration opening 136 inside, and the body of the damping unit 150 includes a first opening 156 and a second opening 158 for connecting the penetration opening 136 to the sealed space (A). Referring to Figs. 4 and 5, the first opening 156 is formed in the lower part of the body of the damping unit 150, whereas the second opening 158 is formed over the first opening 156.

[53] When viscose fluid is injected to the penetration opening 136, the viscose fluid flows through the first opening 156 into the sealed space (A) and the air inside the sealed space (A) is smoothly ejected out through the second opening 158.

[54] The penetration opening 136 includes a first penetration section 137 and a second penetration section 138, each having a different diameter. In the present embodiment, the first penetration section 137 disposed in the lower part has a smaller diameter than that of the second penetration section 138. A fixing member 132 is inserted to and fixed with the first penetration section 137, and the fixing member 132 cuts off the connection between the first penetration section 137 and the second penetration section 138. Thus, it confines the viscose fluid filling the sealed space (A) along the penetration opening 136 airtightly. A contact ring 134 is provided between the fixing member 132 and the first penetration section 137 to improve the airtightness. [55] The driving unit 160 is integrated with the partition unit 140 and the damping unit

150 and rotates together with the damping unit 150. The driving unit 160 includes a joining groove 162 inside to be structurally connected to the hinge axis 16 of the home bar door 15. The joining groove 162 is engaged with the connection protrusion 17 protruded from the hinge axis 16. Thus, when the hinge axis 16 rotates, the entire rotary shaft 130 as well as the driving unit 160 all rotate.

[56] Meanwhile, since a relative motion is made between an end of the driving unit 160 and the cover 120, a washer 174 may be provided between the cover 120 and the driving unit 160.

[57] The present embodiment illustrates the partition unit 140, the damping unit 150, and the driving unit 160, which constitute the rotary shaft 130, integrated into one piece, but it is possible to form them individually and assemble them to form the rotary shaft 130. When the rotary shaft 130 is formed by assembling the individual parts, the material and assembling structure should be selected and designed in consideration of the sealing of the viscose fluid and the strength for transmitting torque.

[58] Hereafter, an assembling process of the rotation-type oil damper 100 will be described.

[59] First, the sealing member 172 is mounted on the partition unit 140 of the rotary shaft

130, and the rotary shaft 130 with the sealing member 172 is inserted to the accommodation space of the housing 110. Herein, the rotary shaft 130 is inserted to the bottom of the accommodation space so that an end of the rotary shaft 130 contacts the bottom of the accommodation space.

[60] Subsequently, the cover 120 is brought to the housing 110 with the washer 174 between the housing 110 and the cover 120. Then, the cover 120 and the housing 110 are connected by four fastening members 126. Viscose fluid, e.g., oil, is injected to the assembly of the housing 110, the rotary shaft 130, and the cover 120.

[61] The viscose fluid is injected to the penetration opening 136 of the rotary shaft 130 through the cover opening 122 of the cover 120. The injected viscose fluid sequentially passes through the second penetration section 138 and the first penetration section 137 and flow into the sealed space (A) surrounded by the partition unit 140 and the housing 110 through the first opening 156. As the viscose fluid flows in, the air in the sealed space (A) is ejected out smoothly through the second opening 158.

[62] As described above, the assembly of the rotation-type oil damper 100 is ended by injecting the viscose fluid into the sealed space (A) and sequentially combining the contact ring and the fixing member 132 with the first penetration section 137 of the penetration opening 136.

[63] Referring to Figs. 6 to 8, an operation of the rotation-type oil damper 100 will be described hereafter. [64] Fig. 6 is a perspective view showing a cross section of the rotation-type oil damper of

Fig. 2 taken along a II-II line. Figs. 7 and 8 are cross sections sequentially showing a rotation of the rotary shaft.

[65] As illustrated in Fig. 6, the housing 110 is provided with a stopper 116 on its inner surface, which is protruded toward the center of the housing 110. The stopper 116 is protruded to the inside of the sealed space (A) to restrict the rotation angle of the rotary shaft 130. The stopper 116 contacts the external surface of the damping unit 150 of the rotary shaft 130 to partition the inner space of the housing 110, specifically, the sealed space (A).

[66] As shown in Fig. 6, a pair of blades 152 is disposed in opposite to each other in the embodiment of the present invention, and thus a pair of stoppers 116, confronting to each other, is provided to correspond to the pair of blades 152.

[67] Meanwhile, the rotation-type oil damper 100 is formed in such a manner that the radius of a cross section of the sealed space (A) changes according to the rotation direction of the blades 152. In other words, the cross section of the sealed space (A) is not an exact circle but it has a different curvature along the rotation direction of the blades 152, as illustrated in Figs. 7 and 8.

[68] Referring to Figs. 7 and 8, the housing 110 of the present embodiment is formed to have the radius of a cross section of the sealed space (A) gradually decrease along the rotation direction of the blades 152. Thus, the gap between the side surface of the accommodation space and the blades 152 is gradually reduced. In other words, the rotation locus (B) of the blades 152 and the inner surface (C) of the accommodation space are formed differently, and the inner surface (C) of the accommodation space is gradually reduced along the rotation direction of the blades 152 and finally it contacts the rotation locus (B) of the blades 152.

[69] In the state shown in Fig. 7, since the accommodation space of the housing 110, i.e., the sealed space (A), is greater than the width of the blades 152, the viscose fluid flows through the gap between the ends of the blades 152 and the inner wall of the sealed space (A). Therefore, the attenuation force is small. However, since the blades 152 rotate in an arrowed direction of Fig. 7, the gap between the sealed space (A) of the housing 110 and the blades 152 becomes narrow gradually. This increases the attenuation force gradually. As illustrated in Fig. 8, as the rotation angle of the blades 152 increases and the blades 152 come to be overly pressured, the viscose fluid slowly moves to the opposite space through the fluid channel 154 while the lower part of the damping unit 150 tightly contacts the bottom of the housing 110 until the attenuation operation is completed. On the contrary, when the blades 152 rotate in the state shown in Fig. 7 in the embodiment of Fig. 8, the attenuation operation is performed reversely.

[70] In a refrigerator according to the embodiment of the present invention, the blades 152 of the oil damper 100 are disposed at the location shown in Fig. 7, when the home bar door 15 is closed. This is because when the home bar door 15 is initially open, the attenuation force produced by the oil damper 100 is small and thus a user can easily open the home bar door 15. When the rotation angle of the home bar door 15 becomes great, the attenuation force by the oil damper 100 increases and thus the rotation speed of the home bar door 15 decreases slowly, as described in the above with reference to Figs. 7 and 8. When the home bar door 15 make a rotation at more than a predetermined angle, the blades 152 are caught by the stoppers 116, as shown in Fig. 8, and stops the rotation. Accordingly, the opening of the home bar door 15 is completed smoothly without any impact. The home bar door 15 closes the opening 13 of the refrigerator door 11 in an operation reverse to the above-described opening operation. [71] While the present invention has been described with respect to the specific embodiments, it will be apparent to those skilled in the art that various changes and modifications may be made without departing from the spirit and scope of the invention as defined in the following claims. Therefore, it should be understood that the above described embodiments are not restrictive but illustrative, and the present invention is not limited by the detailed description but it can be modified within the scope of claims set forth hereafter and their equivalents.

Claims

[1] A hinge assembly for a home bar door of a refrigerator, comprising: a hinge axis extended from a home bar door for opening/closing an opening formed in a refrigerator door; and an oil damper including a housing fixed onto the refrigerator door, a rotary shaft inserted into the housing to thereby form a sealed space to be filled with oil, and connected to the hinge axis to attenuate a rotation force of the hinge axis by forming a blade on one side to move in the oil when the hinge axis rotates, a penetration opening formed to penetrate the rotary shaft and connect the sealed space with an exterior, and a fixing member inserted to and fixed to the penetration opening to seal the penetration opening.

[2] The hinge assembly of claim 1, wherein the rotary shaft includes: a partition unit tightly contacting an inner surface of an accommodation space formed inside the housing to thereby form the sealed space; a damping unit provided with more than one blade disposed to be submerged in the oil of the sealed space and a fluid channel formed to penetrate at least any one of the blades; and a driving unit connected to the hinge axis and rotating together with the blades.

[3] The hinge assembly of claim 1 or 2, wherein the radius of a cross section of the sealed space changes according to a rotation direction of the blades.

[4] The hinge assembly of claim 1 or 2, wherein a gap between the inner wall of the sealed space and ends of the blades decreases gradually as the blades rotate in one direction.

[5] The hinge assembly of claim 2, wherein the fluid channel is formed at the bottom of the blades contacting the bottom of the housing.

[6] The hinge assembly of claim 2, further comprising: a first opening formed in a lower part of the damping unit contacting the bottom of the housing and connecting the penetration opening with the sealed space.

[7] The hinge assembly of claim 2 or 6, further comprising: a second opening formed in an upper part of the damping unit and connecting the penetration opening with the sealed space.

[8] The hinge assembly of claim 1 or 2, wherein the blades are provided in a pair, and the blades are disposed in opposite to each other in the sealed space.

[9] The hinge assembly of claim 1 or 2, further comprising: a stopper protruded from the inner surface of the housing toward the inside of the sealed space and limiting a rotation angle of the rotary shaft.

[10] The hinge assembly of claim 9, wherein the stopper is disposed to contact an external surface of the rotary shaft and partitions the sealed space together with the rotary shaft. [11] A refrigerator, comprising : a body with a food preservation chamber kept at a low temperature inside; a refrigerator door formed in the body to open/close the food preservation chamber and having an opening formed penetrating therethrough; a home bar door disposed to open/close the opening and having a hinge axis protruded from a lower part; and an oil damper comprising: a housing fixed to the refrigerator door; a rotary shaft inserted to the housing to thereby form a sealed space filled with oil and connected to the hinge axis in such a manner that when the rotary shaft rotates, a blade formed in one side moves in the oil to attenuate a rotation force of the hinge axis; a penetration opening formed to penetrate the rotary shaft and connecting the sealed space with an exterior; and a fixing member inserted to and fixed to the penetration opening and sealing the penetration opening.