Patent Publication Number: US-9427084-B2

Title: Rail

Description:
CROSS REFERENCE TO RELATED APPLICATIONS AND CLAIM OF PRIORITY 
     This patent application is a National Phase application under 35 U.S.C. §371 of International Application No. PCT/KR2012/003054, filed 20 Apr. 2012, which claims priority to Korean Patent Application Nos. 10-2011-0082132, filed on 18 Aug. 2011 and 10-2011-0092165, filed on 9 Sep. 2011, entire contents of which are incorporated herein by reference. 
     TECHNICAL FIELD 
     The present invention relates to a rail installed at a home appliance or furniture having a drawer accommodating space in which a drawer is accommodated and capable of pulling the drawer therefrom and pushing the drawer thereinto. 
     BACKGROUND 
     A home appliance such as a refrigerator or the like, furniture, or the like, has a drawer for convenient accommodation, and the drawer is pulled out of or pushed into a drawer accommodating section via rails disposed in the drawer accommodating section. 
     That is, the rail is a device installed at an object such as a home appliance, furniture, or the like, having a drawer accommodating section so that a drawer is pulled out of or pushed into the drawer accommodating section. 
     The rail is configured such that the drawer is pulled out of or pushed into the drawer accommodating section via a fixed rail disposed in the drawer accommodating section provided on the home appliance or furniture and a movable rail installed at the drawer and relatively movable with respect to the fixed rail. 
     Meanwhile, the rail should be provided to endure a load applied toward a lower portion of the drawer by the weight of the drawer and the weight of matters accommodated in the drawer. 
     While the load is applied in a longitudinal direction of the entire rail when the drawer is disposed in the drawer accommodating section, the load by the weight of the drawer and the weight of the matters accommodated in the drawer is moved to the outside of the drawer accommodating section along the drawer when the drawer is pulled out of the drawer accommodating section. 
     Accordingly, the rail should have a structure that can support movement of the load according to the pulling-out and pushing-in of the drawer. 
     In particular, when the drawer is pulled out of the drawer accommodating section, a torsional load that twists the rail in a direction toward a center of the drawer is increased in the rail. Since the torsional load applied to the rail is closely related to a function of the rail and durability of the rail, the rail should have a structure prepared for the torsional load. 
     That is, when the torsional load is continuously and periodically generated from the rail, the fixed rail and the movable rail may be interfered with each other to make it difficult to pull or push the drawer, or the movable rail and the fixed rail may be deformed to increase a gap between the fixed rail and the movable rail (increase a gap between the drawer and the drawer accommodating section). 
     Since these problems may reduce the lifespan of the drawer as well as hinder the function of the drawer, development of the rail configured to stably support the drawer is urgently needed in spite of the torsional load generated by the weight of the drawer and the accommodated matters. 
     However, even though the conventional rails do not have structures that can effectively overcome the torsional load and various researches on the rail having a strong structure against the torsional load are conducted, a rail that can solve the problems due to the torsional load is not developed yet. 
     SUMMARY OF INVENTION 
     In order to solve the problems, an object of the present invention is to provide a rail having a simple structure and capable of stably supporting a load. 
     Another object of the present invention is to provide a rail capable of effectively overcoming a torsional load. 
     Still another object of the present invention is to provide a rail capable of preventing interference between components of the rail due to a torsional load. 
     In order to achieve the aforementioned objects, the present invention provides a rail installed at an object having a drawer accommodating section in which a drawer is accommodated and configured to pull or push the drawer out of or into the drawer accommodating section, the rail including: a movable rail having an accommodating space formed therein, configured to bring the accommodating space in communication with the outside through an open surface, and fixed to a lower surface of the drawer; a rolling body disposed in the accommodating space and installed at both corners opposite to each other in a diagonal direction of the movable rail; and a fixed rail including a fixing section fixed to the drawer accommodating section, a ball support section disposed in the accommodating space and configured to support the rolling body, and a connecting section having one end connected to the ball support section and the other end pulled out of the accommodating space through the open surface and connected to the fixing section, wherein the connecting section is configured to have an angle within a range from 50 to 70 degrees with respect to the fixing section to prevent interference between the open surface and the connecting section even when the movable rail is pressed by the drawer. 
     In this case, the rolling body may be constituted by two rows of balls disposed at both corners opposite to each other in a diagonal direction of the movable rail. Here, the number of balls installed at each of the ball rows may be varied according to an accommodating volume of the drawer and a width of the drawer. 
     In addition, the rolling bodies installed at both corners opposite to each other in the diagonal direction of the movable rail may be configured such that a line connecting centers of the rolling bodies has an angle within a range from 40 to 50 degrees with respect to a lower surface of the drawer. 
     Further, the fixed rail may be formed by bending one plate member such that the ball support section, the connecting section, and the fixing section are integrally formed. 
     Furthermore, the ball support section may further include: a first ball seating surface extending from the connecting section and in which the rolling body, which is disposed at a lower side, of the rolling bodies installed at both corners opposite to each other in the diagonal direction of the movable rail is accommodated; a second ball seating surface in which the rolling body, which is disposed at an upper side, of the rolling bodies installed at both corners opposite to each other in the diagonal direction of the movable rail is accommodated; a bending surface configured to connect the first ball seating surface and the second ball seating surface; and a seating surface supporter having an extension section extending from the second ball seating surface and a bending section formed by bending the extension section and in contact with an upper portion of the connecting section, wherein the first ball seating surface, the bending surface, the second ball seating surface, and the seating surface supporter are configured such that a cross-sectional shape of the ball support section forms a closed curve, and the first ball seating surface and the second ball seating surface are spaced a predetermined distance apart from each other by the extension section. 
     In this case, the extension section may have an angle within a range from 35 to 55 degrees with respect to the lower surface of the drawer. 
     In addition, the ball support section may further include a boundary surface disposed between the connecting section and the first ball seating surface to be located at a position at which the lower rolling body is interfered with an imaginary line extending from the connecting section, and formed by bending the first ball seating surface in a direction of the second ball seating surface. 
     Further, the bending section may be in contact with the connecting section and disposed on the boundary surface. 
     Furthermore, the bending section and the connecting section may be adhered to each other at a partial section of a contact section between the bending section and the connecting section formed in the longitudinal direction of the fixed rail to fix the bending section to the connecting section. 
     Meanwhile, the movable rails may be installed at both opposite ends of the lower surface of the drawer such that the open surfaces are directed toward corners between the side surfaces and the bottom surface of the drawer accommodating section, the fixed rails may be configured such that the fixing sections are fixed to both opposite ends of the drawer accommodating section, and the rolling bodies installed at both corners opposite to each other in a diagonal direction of the movable rails may be configured such that a line connecting centers of the rolling bodies has an angle within a range from 40 to 50 degrees with respect to the lower surface of the drawer. 
     According to the embodiment of the present invention, it is possible to provide a rail having a simple structure and capable of stably supporting a load. 
     In addition, according to the embodiment of the present invention, it is possible to provide a rail capable of effectively overcoming a torsional load. 
     Further, according to the embodiment of the present invention, it is possible to provide a rail capable of preventing interference between components of a rail due to a torsional load. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG. 1  is a cross-sectional view of a rail according to an embodiment of the present invention coupled to a drawer; 
         FIG. 2  is a perspective view of a movable rail shown in  FIG. 1 ; 
         FIG. 3  is a perspective view of a fixed rail shown in  FIG. 1 ; 
         FIGS. 4 and 5  are views for describing methods of installing a fixed rail provided in the rail according to the embodiment of the present invention; 
         FIG. 6  is a cross-sectional view showing a torsional load applied to the rail according to the embodiment of the present invention; and 
         FIGS. 7 and 8  are views for describing a shape of a frame according to an angle formed by a straight line passing through a center of a rolling body installed at the rail according to the embodiment of the present invention and a bottom surface of the drawer. 
     
    
    
     DESCRIPTION OF EMBODIMENTS 
     Hereinafter, an embodiment of the present invention will be described in detail with reference to the accompanying drawings. 
     All terms used herein are equal to the general meaning of terms that can be understood by those skilled in the art unless the context clearly indicates otherwise, and if the terms used herein collide with the general meaning of the terms, the terms will be used as definition used herein. 
     Meanwhile, a configuration or a control method of an apparatus, which will be described below, is provided not to limit the scope of the present invention but provided to describe an embodiment of the present invention. Like reference numerals designate like elements throughout the description. 
     A rail  100  according to an embodiment of the present invention is installed at an object F such as furniture, a home appliance, or the like, having a drawer accommodating section S in which a drawer D is accommodated. The rail  100  includes a movable rail  1  coupled to a lower surface of the drawer D, a fixed rail  7  having one end fixed to a bottom surface or a side surface of the drawer accommodating section S and the other end disposed in the movable rail  1 , and a rolling body  3  disposed in the movable rail  1  and supported by the fixed rail  7  to enable movement of the movable rail  1 . 
     As shown in  FIG. 2 , the movable rail  1  includes a frame  11  fixed to a lower surface of the drawer D and having at least one open end of both opposite ends (front and rear surfaces in the drawing). 
     An accommodating space  13  in which the rolling body  3  and a ball support section  73  (to be described below) of the fixed rail  7  are accommodated is installed in the frame  11 , and the accommodating space  13  is configured to be in communication with the outside of the frame  11  through an open surface  15 . 
     Meanwhile, the movable rail  1  may further include sliding surfaces  17  installed in a longitudinal direction thereof and disposed at an inner circumferential surface of the accommodating space  13  to support the rolling body  3 , and the sliding surfaces  17  may be installed at both corners opposite to each other in a diagonal direction of the frame  11 , respectively. 
     The rolling body  3  includes a lower rolling body  31  disposed at a lower portion of the accommodating space  13  and an upper rolling body  33  disposed at an upper portion in the diagonal direction of the lower rolling body  31 , and the plurality of rolling bodies  31  and  33  may be installed in the longitudinal direction of the frame  11 . 
     A straight line passing through the lower rolling body  31  and the upper rolling body  33  may be inclined with respect to a lower surface of the drawer D by a predetermined angle (see reference character A of  FIG. 4 ). Accordingly, when a torsional load (see reference character f 2  of  FIG. 6 ) is applied to the rail  100  due to the weight of the drawer D and the weight of the accommodated matters, a resistance force of the rail  100  is increased. 
     Meanwhile, when a line connecting centers of the rolling bodies  31  and  33  has a certain angle, in particular, 40 degrees or less, with respect to a bottom surface of the drawer D, since a gap between the upper rolling body  33  and the lower rolling body  31  should be increased in a direction parallel to the bottom surface of the drawer D, a length of an upper surface of the frame  11  (see reference character L 1  of  FIG. 7 ) may be increased to be vulnerable to the torsional load. 
     In addition, since the gap between the upper rolling body  33  and the lower rolling body  31  should be increased in a direction perpendicular to the bottom surface of the drawer D when the line connecting the centers of the rolling bodies  31  and  33  is formed to exceed the certain angle, in particular, 50 degrees, with respect to the bottom surface of the drawer D, the frame  11  may be interfered with the fixed rail  7  (to be described below) when a length (see reference character L 2  of  FIG. 7 ) of the side surface of the frame  11  is increased and the vertical load, the torsional load, or the side surface external force is applied to the frame  11 . 
     Accordingly, an angle A formed by the line connecting the centers of the lower rolling body  31  and the upper rolling body  33  and the bottom surface of the drawer D may be set within a range of 40 to 50 degrees, and thus the rail  100  according to the embodiment can have an increased resistance against the vertical load and the torsional load due to the drawer D and the accommodated matters. 
     Meanwhile, while each of the rolling bodies  31  and  33  shown in  FIG. 2  is shown as the rolling body  3  having a ball or a spherical shape, the rolling body installed at the rail  100  according to the embodiment of the present invention may be modified in various shapes different from the shown shape as long as the movable rail  1  is movable by the rolling body. 
     When the rolling bodies  31  and  33  have a ball shape or a spherical shape, the rolling bodies  31  and  33  may be constituted by a pair of ball arrays (not shown) installed in the longitudinal direction of the movable rail  1  and provided at both corners opposite to each other in a diagonal direction of the movable rail  1 . Here, the number of balls provided in each of the ball arrays (not shown) may be varied according to an accommodating volume of the drawer D and a width of the drawer D. 
     In addition, when each of the rolling bodies  31  and  33  is provided in plural, the rail  100  according to the embodiment of the present invention may further include a ball retainer (see reference numeral  5  of  FIGS. 4 and 5 ) disposed in the accommodating space  13  and in which each of the rolling bodies  31  and  33  is accommodated. 
     The ball retainer  5  is configured to maintain a gap between the rolling bodies  31  and  33  in the accommodating space  13  while rotatably supporting the rolling bodies  31  and  33 . While the ball retainer  5  may include a retainer frame (not shown) disposed in the accommodating space  13  and an accommodating groove (not shown) provided in the retainer frame (not shown) to accommodate the rolling bodies  31  and  33 , the ball retainer  5  may be modified in various types that can implement the above-mentioned functions. 
     As shown in  FIG. 3 , the fixed rail  7  includes a fixing section  71  fixed to the drawer accommodating section S, the ball support section  73  disposed in the accommodating space  13  to support the rolling body  3 , and a connecting section  75  having one end connected to the ball support section  73  and the other end disposed at the outside of the frame  11  and connected to the fixing section  71  via the open surface  15 . 
     The fixed rail  7  may be configured to include the ball support section  73 , the connecting section  75 , and the fixing section  71  by folding one plate member. 
     The fixing section  71  may be configured to be fixed to the bottom surface of the drawer accommodating section S as shown in  FIG. 5 , or may be configured to include a flange  711  configured to fix the fixed rail  7  to a sidewall of the drawer accommodating section S as shown in  FIG. 4 . 
     The connecting section  75  is configured to be inclined with respect to the fixing section  71  by a predetermined angle B. Accordingly, even when the vertical load or torsional load (see reference character f 2  of  FIG. 6 ) is applied to the rail  100  by the weight of the drawer D and the weight of the accommodated matters, interference between the movable rail  1  and the fixed rail  7  can be prevented. The angle B between the connecting section  75  and the fixing section  71  may be set within a range from 50 to 70 degrees, in particular, 60 degrees. 
     When the connecting section  75  has an angle larger than 70 degrees with respect to the fixing section  71 , since the vertical load and the torsional load are applied to the frame  11 , the connecting section  75  and the frame  11  may be interfered with each other to disturb the pulling-out or pushing-in of the drawer D. In addition, when the connecting section  75  has an angle smaller than 50 degrees with respect to the fixing section  71 , the frame  11  may come in contact with the bottom surface of the drawer accommodating section S when the vertical load or the torsional load is applied. 
     In addition, when the connecting section  75  is inclined to have an angle within a range from 50 to 70 degrees with respect to the fixing section  71 , a resistance against the side surface external force (or a side surface collision) applied to the side surface of the drawer D may be increased when the drawer D is pulled out. 
     That is, provided that the drawer D is pulled out of the drawer accommodating section S and a side surface external force f 1  as shown in  FIG. 1  is applied to the side surface of the drawer D, when the connecting section  75  has an angle smaller than 50 degrees with respect to the fixing section  71 , the side surface external force f 1  cannot be easily supported, and when the angle is larger than 70 degrees, an interference between the connecting section  75  and the frame  11  by the side surface external force f 1  may occur. However, when the connecting section  75  has the inclination angle B within a range from 50 to 70 degrees with respect to the fixing section  71 , the side surface external force f 1  can be effectively supported to minimize the above-mentioned problems. 
     The ball support section  73  may include a first ball seating surface  731  extending from the connecting section  75  and configured to accommodate the lower rolling body  31 , a second ball seating surface  733  connected to the first ball seating surface  731  through a bending surface  735  and configured to accommodate the upper rolling body  33 , and a seating surface supporter  737  extending from the second ball seating surface  733  and configured to come in contact with the connecting section  75 . 
     The second ball seating surface  733  is configured to support the upper rolling body  33  to support most of the vertical load of the drawer D and the accommodated matters, and the first ball seating surface  731  is configured to support the lower rolling body  31  to support the torsional load (see reference character f 2  of  FIG. 6 ) applied to the second ball seating surface  733  and the frame  11 . 
     Further, the first ball seating surface  731  and the connecting section  75  may be connected to each other while forming a boundary surface P. 
     That is, the first ball seating surface  731  may be connected to the connecting section  75  and bent in a direction in which the second ball seating surface  733  is formed such that the lower rolling body  31  is disposed at a position interfered with an imaginary line extending from the connecting section  75 . 
     When the load caused by the drawer D and the accommodated matters is applied to the rail  100 , an effect of preventing separation of the lower rolling body  31  between the frame  11  and the ball support section  73  is provided. 
     Meanwhile, the seating surface supporter  737  includes an extension section  7371  extending from the second ball seating surface  733  in a direction of the connecting section  75  as a means configured to increase a resistance of the rail  100  when the vertical load and the torsional load caused by the drawer D and the accommodated matters are applied to the rail  100 , and a bending section  7373  formed by bending one end of the extension section  7371  and configured to come in contact with an upper portion of the connecting section  75 . 
     In this case, the extension section  7371  may be inclined to have a predetermined angle C within a range from 35 to 55 degrees with respect to the bottom surface of the drawer D, and in particular, the extension section  7371  may have an angle of 45 degrees with respect to the bottom surface of the drawer D (an angle of 45 degrees with respect to the bottom surface of the drawer accommodating section S). 
     Provided that the extension section  7371  is disposed parallel to the bottom surface of the drawer D (an angle of 35 degrees or less) or has an angle of 55 degrees or more, a force applied to the lower rolling body  31  and the upper rolling body  33  cannot be effectively overcome when the vertical load and the torsional load are applied to the rail  100 . 
     Meanwhile, the ball support section  73  may be formed by bending one plate member. In this case, the seating surface supporter  737  may be configured to come in contact with the connecting section  75  to form a closed curve of a cross-sectional shape of the ball support section  73  and configured to form a predetermined space such that the first ball seating surface  731  is spaced a predetermined distance apart from the second ball seating surface  733 , and the bending section  7373  of the seating surface supporter  737  may be adhered to a position (the connecting section  75 ) near the first ball seating surface  731 , the boundary surface P of the first ball seating surface  731 , and so on. 
     This is because the load of the drawer D and the accommodated matters transmitted through the rolling bodies  31  and  33  can be effectively supported by the ball support section  73 . 
     That is, when the load (the vertical load and the side surface external force) of the drawer D and the accommodated matters is transmitted to the first ball seating surface  731  and the second ball seating surface  733  through the rolling bodies  31  and  33 , since the gap between the first ball seating surface  731  and the second ball seating surface  733  can be maintained as the bending section  7373  of the seating surface supporter  737  is adhered to the connecting section  75  to support the load while the extension section  7371  of the seating surface supporter  737  is compressed, even when the fixed rail  7  has the ball support section  73  formed by bending a thin plate member, the load transmitted from the rolling bodies  31  and  33  can be effectively supported. 
     In order to maximize the above-mentioned effects, the bending section  7373  of the seating surface supporter  737  may be adhered and fixed to the connecting section  75  to increase adhesion to the connecting section  75  through welding or the like. 
     However, adhesion and fixing of the bending section  7373  and the connecting section  75  may be performed by continuously or partially fixing the bending section  7373  to the connecting section  75  in the longitudinal direction of the fixed rail  7 . 
     That is, the bending section  7373  and the connecting section  75  may be configured such that the bending section  7373  and the connecting section  75  are adhered to at least a portion of a contact section between the bending section  7373  and the connecting section  75  formed in the longitudinal direction of the fixed rail  7 , fixing the bending section  7373  to the connecting section  75 . 
     Hereinafter, functions and effects of the rail  100  according to the embodiment of the present invention having the above-mentioned structure will be described with reference to  FIG. 6 . 
     When a user pulls the drawer D out of the drawer accommodating section S in a state in which the drawer D is accommodated in the drawer accommodating section S, the movable rail  1  fixed to the lower surface of the drawer D is moved through guidance of the fixed rail  7 , and here, the rolling bodies  31  and  33  are rotated between the movable rail  1  and the fixed rail  7  to assist movement of the movable rail  1 . 
     Meanwhile, when the drawer D is pulled out of the drawer accommodating section S as well as when the drawer D is disposed in the drawer accommodating section S, the torsional load f 2  is applied to the rail  100  by the weight of the drawer D and the weight (the load) of the accommodated matters. 
     Here, since the rolling bodies  31  and  33  disposed in the frame  11  of the movable rail  1  are installed at both corners opposite to each other in the diagonal direction of the frame  11 , respectively, and the line connecting the centers of the rolling bodies  31  and  33  has the angle A of 40 to 50 degrees with respect to the lower surface of the drawer D, the torsional load f 2  applied in the same direction as shown in the drawing can be effectively offset. That is, since the lower rolling body  31  is disposed closer to the central direction of the drawer D than the upper rolling body  33 , the lower rolling body  31  can endure the torsional load. 
     In addition, since the seating surface supporter  737  is installed at the ball support section  73  of the fixed rail  7  and the extension section  7371  of the seating surface supporter  737  is supported by the connecting section  75  through the bending section  7373 , even when the lower rolling body  31  is pressed by the frame  11  due to the torsional load f 2 , the bending section  7373  supports the load while the extension section  7371  is compressed with adhesion to the connecting section  75 . Accordingly, the upper rolling body  33  and the lower rolling body  31  can be securely supported, and deformation and loss of function of the rail  100  due to the torsional load f 2  can be prevented. 
     In addition, in case of the conventional rail (not shown), when the torsional load f 2  or the side surface external force f 1  is applied to the rail, while the movable rail is interfered with the fixed rail to make it difficult to pull or push the drawer, since the rail  100  according to the embodiment of the present invention is configured such that the connecting section  75  has the angle B of 50 to 70 degrees with respect to the bottom surface of the fixing section  71  or the drawer accommodating section S, the above-mentioned problems can be solved. 
     That is, since the connecting section  75  installed at the rail  100  according to the embodiment of the present invention is inclined with respect to the fixing section  71  by the predetermined angle B to pass through the open surface  15 , connect the fixing section  71  and the ball support section  73 , and maintain a certain distance from the open surface  15 , even when the frame  11  is moved clockwise by the torsional load f 2  or the drawer D is moved to one side by the side surface external force f 1 , an interference between the frame  11  and the connecting section  75  can be prevented. 
     While the invention has been shown and described with reference to certain example embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims. 
     INDUSTRIAL APPLICABILITY 
     Since the rail according to the embodiment of the present invention has a simple structure and can stably support the load of the drawer to enable easy manufacture thereof, and an influence due to the torsional load can be minimized to improve durability of the drawer and reduce generation of noises, the rail can be usefully utilized in a drawer manufacturing field.