Patent Abstract:
A telescopic drawer slide including first, second and third drawer slides, each having a longitudinal length with a web and arcuate arms along the longitudinal margins of the web, the second drawer slide being nested within the arcuate arms of the first drawer slide, and the third drawer slide being nested within the arcuate arms of the second drawer slide. There is a lock between the second drawer slide and the first drawer slide, the lock having a biased tab rotatably coupled to the second drawer slide and an emboss on the first drawer slide. The tab moves into a portion of the emboss upon movement over the emboss, thereby preventing the second drawer slide from closing relative to the third drawer slide.

Full Description:
CROSS-REFERENCE TO RELATED APPLICATIONS  
       [0001]    This application claims the benefit of U.S. provisional application No. 60/249,137, filed on Nov. 16, 2000, the contents of which are incorporated herein by reference. 
     
    
     
       BACKGROUND OF THE INVENTION  
         [0002]    The present invention relates to drawer slides and more particularly to a telescopic frictional drawer slide.  
           [0003]    Telescopic slides for file drawers and the like are often desirable for use in cabinets and other rack mounted applications. Such slides permit easy access to the interior of the drawer. The slides maintain the drawer in a horizontal position regardless of how far the drawer is withdrawn from the cabinet. The slides are also useful in the mounting of extendable shelves and cabinets. A typical drawer will often have two slides securing the drawer to the cabinet or enclosure, with the slides attached to each of the outside vertical walls of the drawer.  
           [0004]    Frictional drawer slides typically have members that rub against each other in sliding engagement. One advantage of frictional drawer slides is that there are no ball bearings. One disadvantage of typical frictional drawer slides is noise of operation. Another disadvantage of typical frictional drawer slides is difficulty in opening because of a large amount of friction, especially after wear.  
         SUMMARY OF THE INVENTION  
         [0005]    A telescopic drawer slide according to an embodiment of the present invention includes first, second and third drawer slides each having a longitudinal length with a web, and arms along the longitudinal margins of the web. The second drawer slide is nested within the arcuate arms of the first drawer slide. The third drawer is nested within the arcuate arms of the second drawer slide. The telescopic drawer slide has a lock between the second drawer slide and the first drawer slide, the lock having a biased tab rotatably coupled to the second drawer slide and an emboss on the first drawer slide. The tab moves into a portion of the emboss upon movement over the emboss, thereby preventing the second drawer slide from closing relative to the third drawer slide.  
           [0006]    In an embodiment, the tab is biased by gravity. In an alternative embodiment, the tab is biased by a spring. The tab is moved over the emboss by the third drawer slide thereby allowing the second drawer slide to close relative to the first drawer slide after closing of the third drawer slide relative to the second drawer slide.  
           [0007]    In an embodiment, the emboss has an angled portion tapering toward the arcuate arms of the first drawer slide, a wide portion with longitudinal edges, and an edge leading to a narrow portion. As the second drawer slide is withdrawn from the first drawer slide, the tab moves to the narrow portion and is restrained by the edge from closing.  
           [0008]    The web of the second drawer slide has a hat section extending along the longitudinal length. The hat section of the second drawer slide clearing the emboss on the first drawer slide. The web of the third drawer slide has a hat section extending along the longitudinal length. The hat section of the third drawer slide clearing and surrounding the hat section of the second drawer slide.  
           [0009]    In an embodiment, the arms of the first drawer slide have a lateral portion that is bowed toward the arms of the second drawer slide. The arms of the second drawer slide are nested within the arms of the first drawer slide defining a contact area along a tip of the bowed portion of the arms and a reservoir adjacent to the contact area.  
           [0010]    In another additional embodiment, the arms of the third drawer slide have a lateral portion that is bowed toward the arms of the second drawer slide. The arms of the third drawer slide are nested within the arms of the second drawer slide defining a contact area along a tip of the bowed portion of the arms of the third drawer and a reservoir adjacent to the contact area.  
           [0011]    In an additional embodiment, the telescopic drawer slide has a lock between the third drawer slide and the second drawer slide. The lock has a biased tab on the third drawer slide and a hole in the second drawer slide. The biased tab enters the hole when the third drawer slide is withdrawn from the second drawer slide.  
           [0012]    In an alternative embodiment, the lock between the third drawer slide and the second drawer slide has a biased arm with a cutout rotatably coupled to the third drawer slide and a tab on the second drawer slide oriented toward the third drawer slide. The tab enters the cutout as the third drawer slide is withdrawn from the second drawer slide. In an additional embodiment, a lock release moves the biased arm to move the cutout away from the tab.  
           [0013]    Additionally, a telescopic drawer slide according to an embodiment has a stop between the second drawer slide and the first drawer slide. A portion of the web of the second drawer slide is punched toward the first drawer slide and a portion of the vertical web of the first drawer slide is punched toward the second drawer slide.  
           [0014]    In an alternative embodiment, the lock between the second drawer slide and the first drawer slide has a lever biased toward the first drawer slide coupled to the second drawer slide, a tab coupled to the lever, and a hole in the first drawer slide. The tab moves into the hole in the first drawer slide as the second drawer slide is withdrawn from the first drawer slide, thereby preventing the second drawer slide being closed relative to the first drawer slide. In an additional embodiment, a c-shaped tab is formed in the web of the third drawer slide. The c-shaped tab is biased toward the second drawer slide. The c-shaped tab moves the lever and the tab away from the first drawer slide allowing the second drawer slide to be closed relative to the first drawer slide member.  
           [0015]    In yet another embodiment, the telescopic drawer slide has a detent. The detent includes a hole in the lever of the second drawer slide and a raised bump on the c-shaped tab of the third drawer slide. When the third drawer slide is closed within the second drawer slide, the bump fits inside of the hole in the lever. The detent prevents movement of the third drawer slide relative to the second drawer slide until a predetermined amount of force is used to pull the third drawer slide from the second drawer slide. The detent causes the second drawer slide to be withdrawn from the first drawer slide prior to the withdrawing of the third drawer slide from the second drawer slide.  
           [0016]    A telescopic drawer slide according to an embodiment of the present invention fits within a space between a drawer and a cabinet of about 0.375 inches wide by about 1 inch in height. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0017]    Other features and advantages of the preset invention will be set forth in part in the description which follows and in the accompanying drawings, wherein:  
         [0018]    [0018]FIG. 1 is a cross-section view of a telescopic drawer slide according to an embodiment of the present invention;  
         [0019]    [0019]FIG. 2 is a perspective view of a leading edge of an inner slide member according to an embodiment of the present invention;  
         [0020]    [0020]FIG. 3 is a perspective view of a lock between the inner slide member and the intermediate slide member according to a first embodiment of the present invention;  
         [0021]    [0021]FIGS. 4 a  to  4   c  top views of alterative spring formed stops according to a first embodiment of the present invention;  
         [0022]    [0022]FIG. 5 is an elevational view taken from a side of a drawer slide showing the locking mechanism between the inner and intermediate slide members according to a second embodiment of the present invention;  
         [0023]    [0023]FIG. 6 is a perspective view of the locking relationship between the inner and intermediate slide members according to a second embodiment of the present invention;  
         [0024]    [0024]FIG. 7 is another perspective view of a lock between the intermediate slide member and the outer slide member according to an embodiment of the present invention;  
         [0025]    [0025]FIG. 8 is a perspective view showing a lock between the intermediate slide member and the outer slide member according to an alternative embodiment of the present invention;  
         [0026]    [0026]FIG. 9 is a cross-sectional view taken along line A-A of FIG. 9; and  
         [0027]    [0027]FIG. 10 is a perspective view of a lock between the intermediate and outer slide members according to an alternative embodiment of the present invention. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0028]    A drawer slide incorporating the present invention is shown in FIG. 1. As shown in FIG. 1, an exemplary drawer slide has three separate slide members. The three slide members shown in FIG. 1 are an outer slide member  10 , an intermediate slide member  20 , and an inner slide member  30 . The three slide members are all slidably connected to one another. In alternative embodiments, the drawer slide has 4 or more slide members.  
         [0029]    In the following description, it is assumed that the inner slide member is attached to a drawer and the outer slide member is attached to a cabinet. In practice, the outer slide member may be attached to a drawer and the inner slide member may be attached to a cabinet. Furthermore, the same drawer slide according to an embodiment of this invention, can be mounted on either side of the drawer without any modification.  
         [0030]    The slide members fit within each other when the drawer is closed. In an embodiment, the drawer slide, in a closed position, fits inside of a space between the drawer and the cabinet having a size of approximately 0.375 inches wide by approximately 1 inch in height. In order to achieve this, the slide members increase in thickness from inner to intermediate to outer member. The inner slide member  30  nests within the intermediate slide member  20  which in turn nests within the outer slide member  10 . As shown in FIG. 1, the outer slide member  10  has an outer vertical web  12  and two outer slideways  14 . Each slideway has a horizontal portion  16  extending from the outer vertical web toward the drawer, and a vertical portion  18  that is oriented inward. The horizontal and vertical portions of the slideway in combination with a portion of the outer vertical web  12  encompass intermediate slideways of the intermediate slide member  20 .  
         [0031]    The horizontal portions  16  of the outer slideways are slightly concave inward. As explained below, the bowed in horizontal portions  16  of the outer slide member are slid upon by the outside of intermediate slideways of the intermediate slide member  20 . The outside of the intermediate slideways of the intermediate slide member  20  contact only the top of the curve in the middle of the horizontal portions  16  of the outer slide member  10 . This reduces friction between the outer slide member  10  and the intermediate slide member  20 . Likewise, because the outer slideways are bowed inward, small pockets  19  are formed in slideway edges where the outer vertical web  12  meets the horizontal portion  16  and where the horizontal portion  16  meets the vertical portion  18 . The small pockets  19  run all along the length of the outer slide member  10  and function as reservoirs for lubricating material. The small pockets  19  also function as a depository for minute particles of materials produced during the wear of mating surfaces during use of the slide.  
         [0032]    The outer vertical web  12  of the outer slide member  10  contains a number of holes that allow the outer slide member to be attached to either a cabinet or to a drawer. In an embodiment of the present invention, the outer slide member is attached to the cabinet using screws. In alternative embodiments, the outer slide member is attached using other attachment devices, such as nails, nuts, glue, and rivets. In yet another alternative embodiment of the present invention one or more brackets may be attached to the outer slide member, with the brackets themselves being attached to a cabinet or drawer.  
         [0033]    The intermediate slide member  20  has intermediate slideways  25 . The intermediate slideways  25  are formed with a horizontal section attached to the intermediate vertical web  22 . Each slideway has a vertical section facing the opposite slideway. The horizontal section and vertical section, in combination with the intermediate vertical web, forms an enclosed space that encloses slider sections of the inner slide member  30 . In contrast to the horizontal portion of the slideways of the outer slide member  10 , the horizontal portions of the intermediate slideways  25  are not concave. The inside of the intermediate slideways  25  contain sharp corners. The outside corners of the intermediate slideways are curved to help form the pockets  19  on the inside of the outer slideways discussed above.  
         [0034]    The intermediate slide member  20  also has an intermediate vertical web  22 . A portion of the intermediate vertical web  22  in the vertical center of the slide member is bent toward the drawer to form a hat section  24 . The hat section  24  has two angled portions leading from the intermediate vertical web to a vertical portion that is positioned closer to the drawer than the intermediate vertical web. The hat section is designed to fit over the screws or other means used to attach the outer slide member to a cabinet or drawer. Additionally, the hat section adds strength and stability to the intermediate slide member. In one embodiment, the hat section is recessed inward enough to clear the heads of number  8  screws or equivalent screw heads.  
         [0035]    The inner slide member  30  has slider sections  31  that slide inside of the intermediate slideways of the intermediate slide member. The slider sections  31  are made of a vertical piece that has been bent 180 degree back upon itself, forming an edge  32  which slides on the inside of the intermediate slideway  25 . The edge  32  provides for point contact between the inner slide member  30  and the intermediate slide member  20 , reducing friction and the force necessary to extend and retract the inner slide member.  
         [0036]    The inner slide member also has an inner hat section  33 . The inner hat section  33  has angled sides  34  leading to a vertical portion  35 . In an embodiment of the present invention, the vertical portion  35  of the inner slide member contains holes for attachment to either a cabinet or a drawer. In one embodiment, the inner slide member is attached using screws. In alternative embodiments, the inner slide member may be attached using other attachment devices, such as nails, nuts, glue, and rivets. The hat section  33  of the inner slide member is raised far enough away from the hat portion of the intermediate slide member to allow clearance of a number  8  screws or equivalent screw head. The hat section  33  of the inner slide member  30  is raised far enough away from the hat portion of the intermediate slide member to prevent contact between the hat sections of the intermediate and inner slide members.  
         [0037]    The inner slide member has two ends. A first end is facing out from a closed position and forms one end point of the slide as it is opened. The first end of the inner slide member has a tab across the hat section. The tab functions as a stop because the tab is hit by the intermediate slide member when the inner slide member is fully closed.  
         [0038]    A second end of the inner slide member is opposite to the first end. The inner slide member is removable from the intermediate slide member. After removal from the intermediate slide member, the second end of the inner slide member must be oriented to the intermediate slide member for reinsertion. As shown in FIG. 2, the second end of the inner slide member is tapered, and therefore the ends of the sliders are angled back into the inner slide member. The tapered second end of the inner slide member allows the slide member to align with an end of the intermediate slide member. The second end of the inner slide member is also chamfered to further assist in alignment between the inner slide member and the intermediate slide member.  
         [0039]    The tapered second end is provided for in the preformed shape of the inner slide member. The taper eliminates the need to remove burrs caused by shearing the inner slide member. This is advantageous because the presence of burrs may lead to premature failure of the surface, thus increasing interference and later increasing the force required to move the inner slide member during drawer slide use.  
         [0040]    The inner, intermediate, and outer slide members slide in relation to one another. In order to keep a drawer sliding evenly on both sides, the drawer slides are designed to open and close the same way in a process which may be termed sequencing. By using locks and detents, further described below, the intermediate slide member  20  is pulled out of the outer slide member  10  first. Once the intermediate slide member  20  has been fully extended from the outer slide member  10 , the inner slide member  30  is released from the intermediate slide member  20 . Likewise, when closing a drawer slide, the inner slide member  30  is closed back inside of the intermediate slide member  20 . After the inner slide member  30  is completely inside of the intermediate slide member  20 , the intermediate slide member  20  is released to close into the outer slide member  10 .  
         [0041]    In an alternative embodiment of the present invention, the inner slide member  30  opens from the intermediate slide member  20  before the intermediate slide member opens from the outer slide member  10 . Likewise, in the alternative embodiment, the intermediate slide member  20  closes inside of the outer slide member  10  before the inner slide member  30  closes inside of the intermediate slide member  20 .  
         [0042]    In a first embodiment of the present invention, shown in FIG. 3, a lock is placed between the inner slide member  30  and the intermediate slide member  20  so that someone cannot pull the inner slide member  30  out of the intermediate slide member  20  beyond a preselected point. In the first embodiment, the inner slide member has a spring formed stop  26  located approximately one third of the way from the second end of the inner slide member on the inside of the inner slide member. The spring formed stop has a first portion that extends toward the intermediate slide member  20  from the inner slide member. At the end of the first portion is a rectangular portion  28 . The rectangular portion  28  is biased toward to the intermediate slide member by the first portion.  
         [0043]    The intermediate slide member has a hole  27  to catch the rectangular section of the spring formed stop. The intermediate slide member has two ends. A first end of the intermediate slide member is oriented to the second end of the inner slide member when the inner slide member is extended. In an embodiment of the present invention, the hole  27  that catches the spring formed stop is positioned near the first end of the intermediate slide member. A second end of the intermediate slide member is oriented opposite to the first end of the intermediate slide member.  
         [0044]    As the spring formed stop passes over the hole  27  in the intermediate slide member, the spring formed stop springs into the hole. Once in the hole, the spring formed stop impacts the edge of the hole in the intermediate slide member and prevents the inner slide member from being further extended from the intermediate slide member. This prevents accidental removal of the inner slide member of the intermediate slide member and thus, the accidental removal of the drawer from the cabinet. The removal of the inner slide member from the intermediate slide member, and hence the removal of the drawer from the cabinet is possible, by manually pressing the spring formed stop  26  out of the hole  27  in the intermediate slide member.  
         [0045]    The placement of the spring formed stop  26  also creates staging, because once the inner slide member is totally extended, and the spring formed stop  26  is in the hole  27  of the intermediate slide member, all of a drawer opening force pulls the intermediate slide member  20  out of the outer slide member  10 .  
         [0046]    In an additional embodiment of the present invention, the hole  27  in the intermediate slide member and the spring formed stop  26  are designed so that the spring formed stop does not catch the edge of the hole when the drawer is being closed. Therefore, the spring formed stop does not prevent the inner slide member from closing inside of the intermediate slide member.  
         [0047]    As shown in FIGS. 4 a  to  4   c,  the spring formed stop  27  is attached to the inner slide member. In an embodiment, shown in FIG. 4 a,  the rectangular portion  28  is formed as a rectangular stamping. In an alternative embodiment, shown in FIGS. 4 b  and  4   c,  the rectangular portion is a three dimensional rectangular structure attached to the first portion of the spring formed stop. The spring formed stop  27  may be attached using one or more fasteners, such as rivets, that go through one or more holes  29  in the spring formed stop and one or more holes in the inner slide member. Alternatively, the spring formed stop  27  may be attached by staking, where a portion of the inner slide member is stamped to fit around the spring formed stop.  
         [0048]    In a second embodiment of the present invention a different type of lock is used between the inner and intermediate slide members. In this alternative embodiment, shown in FIG. 5, the lock, once initiated, prevents the inner slide member from being opened further or closed in relation to the intermediate slide member.  
         [0049]    In the second embodiment of the present invention, the inner slide member has a spring biased lever  37  positioned inside of the inner hat section. The lever  37  has an angled portion  38  that is oriented outward. The lever also has a square cut out  39  along an edge adjacent to the intermediate slide member. A spring biases the lever  37  so that the square cut out  39  is always being pressed outwards toward the intermediate slide member  20 . In an embodiment of the present invention, the lever  37  is attached to the inner slide member  30  by means of a rivet. In alternative embodiments, the lever may be attached using nuts and bolts, screws, or other means of attachment, that allow the lever to rotate around the point of attachment.  
         [0050]    Also in the second embodiment of the present invention, the intermediate slide member  20  has a segment of the angled portion of the hat section  24  stamped inward. The inward stamped portion extends into the hat section  33  of the inner slide member  30  forming a protrusion  40 . As the inner slide member  30  and the attached spring biased lever  37  passes the protrusion  40  of the intermediate slide member, the angled portion  38  of the lever is pressed downward due to the angle of impact. The force necessary to further move the inner slide member and the lever may be manipulated by changing the strength of the spring biasing the lever. The lever continues to be pushed against the force of the spring until the square cut out  39  of the lever is positioned over the protrusion  40  of the intermediate slide member  20 . At this point, the force of the spring forces the lever down over the protrusion, and the lever is locked in place. In order to release the inner slide member from the lock, the lever must be moved over the protrusion. In an embodiment of the present invention, a user simply pushes the lever against the spring force, thus moving the lever over the protrusion and allowing the inner slide member to be either opened or closed.  
         [0051]    In an alternative embodiment, shown in FIG. 6, attached to the inner slide member is a release lever  41  that releases the lock. The release lever  41  is attached to the inner slide member  30  with shoulder rivets  42 . The use of shoulder rivets allows the release lever to be translated, along the length of the inner slide member. Pushing the release lever  41 , particularly along a tab  43  at a forward end of the release lever  41 , causes an end  44  of the release lever  41  to press against the angled edge  38  of the lever  37 . This results in a rotation of the lever  37  such that the square surface  39  of the lever  37  is rotated over the protrusion  40 , thus releasing the lock.  
         [0052]    A locking mechanism also exists between the intermediate slide member and the outer slide member. The locking mechanism prevents the intermediate slide member from closing inside of the outer slide member until the inner slide member is closed inside of the intermediate slide member. As shown in FIG. 7, in an embodiment of the present invention, a tab  46  is attached to the second end of the intermediate slide. The tab is “T” shaped. The tab  46  is attached using a rivet  48 . In alternative embodiments, the tab  46  may be attached using other attachments means that allow the tab to rotate around the point of attachment, such as a nut and bolt.  
         [0053]    The “T” shape provides a rotational limit for the tab, because the top of the “T” impacts the slideways of the outer slide member. The tab is moved by the force of its own weight depending on the orientation of the slide. This allows the slide to be used on either the left or right side of a drawer, and allows the slide to be affixed with either the outer slide member or the inner slide member attached to a drawer.  
         [0054]    The tab  46  has a first area  49  adjacent to the attachment that flares to a larger width toward the second end of the intermediate slide member. The tab has a second area  50  that extends outward from the end of the intermediate slide member. The second area forms the top of a “T” shape and has edges  51  that are folded down to impact an emboss  52  located on the outer slide member. When in a neutral position the second area extends out from the intermediate slide member in parallel to the intermediate slide member. When biased by the weight of the tab  46 , the second area slopes downward on an angle and locks in the emboss. When locked in the emboss  52 , the angle of the second area of the tab is such that the tab blocks the path of the inner slide member. The inner slide member impacts the angled second area and the angle of impact forces the tab back to a neutral position, thus enabling the tab to clear the emboss  52 .  
         [0055]    The tab  40  also has reliefs  60  between the first and second area. The reliefs  60  are small cutouts in the tab. The reliefs  60  prevent distortion of the second end of the intermediate slide member which impacts the tab when the tab is engaged in the emboss  52  on the outer slide member  10 .  
         [0056]    The emboss  52  on the outer slide member  10  functions as a stop for the tab  46  on the intermediate slide member  20 . The emboss  52  is arrow shaped with the arrow head pointing toward the closed position. Thus, the emboss  52  has an angled portion  54 , a horizontal portion  56  and a vertical edge  57  from the horizontal portion to a narrow stem  58 .  
         [0057]    As the intermediate slide member is extended, the angled head of the emboss  52  allows the tab  46  to pass over the angled portion  54  and onto the horizontal portion  56  despite the weight of the tab. Once past the horizontal portion  56 , the tab reaches the vertical edge  57  and narrow stem and the weight of the tab forces the tab down the vertical edge  57  against the narrow stem  58 . When a closing force is applied to the intermediate slide member, the downward angled second area of the tab impacts the vertical edge  57  of the emboss and is immobile until the inner slide member acts on the downward angled second area of the tab to return the tab to the neutral position. The force of the inner slide member counteracts the weight of the tab and pushes the tab upward so that the tab can then clear the emboss  52 . Once clear of the emboss  52 , the intermediate slide member  20  may close inside of the outer slide member.  
         [0058]    In an additional embodiment of the present invention, the horizontal edge  56  transitions into an edge more than 90 degree inward. The additional angle beyond 90 degrees prevents the tab from disengaging from the emboss due to vibration, bounce or excessive force.  
         [0059]    A lock is present to prevent the intermediate slide member  20  from coming completely out of the outer slide member  10 . Near the second end of the intermediate slide member, a portion of the angled sides of the hat section of the intermediate slide section are punched downward toward the outer slide member  10  forming a stop.  
         [0060]    The outer slide member has a portion in the outer vertical web  12  punched upward toward the intermediate slide member  20  that prevents the downward punched area of the intermediate slide member from moving past. In an embodiment, the raised portion of the vertical web of the outer slide member has a hole where two strips of metal are oriented toward the intermediate slide member. The two strips of metal impact the downward punched areas of the intermediate slide member. This prevents the accidental removal of the intermediate slide member from the outer slide member.  
         [0061]    In an alternative embodiment of the present invention, a different lock is used to force the inner slide member  30  to close inside of the intermediate slide member  20 , before the intermediate slide member  20  closes inside of the outer slide member  10 . As shown in FIGS. 8, 9, and  10 , the vertical portion  38  inner slide member, at a point near the second end, has a “c-shaped” cutout section  70 . Within the “c-shaped” cutout section  70  is a tab  72 . The tab  72  is bent toward the intermediate slide member  20 . On the tab  72  is a button  74 .  
         [0062]    Attached to the intermediate slide member  20  near the second end of the intermediate slide member  20  is a receiver  80 . The receiver  80  is attached to the intermediate slide member using a rivet  82 . In an additional embodiment, the receiver  80  may be attached using nuts and bolts, screws, or other means of attachment that allow the receiver to flex inward and outward in relation to the intermediate slide member  20 .  
         [0063]    The receiver  80  extends from the point of attachment toward the first end of the intermediate slide member. The receiver has a head  84  with a hole  86  in it. The head  84  also has flanges  88  which extend through a hole in the intermediate slide member to the outer vertical web  12  of the outer slide member  10 . The flanges are straight on the side closer to the second end of the intermediate slide member, and angled on the other side. The receiver has a springlike aspect and keeps the flanges in contact with the outer slide member. At the end of the receiver closest to the first end of the intermediate slide member, the receiver  80  has a lip  90  upturned toward the inner slide member. The upturned lip helps to guide the “c-shaped” tab  82  into the receiver.  
         [0064]    The outer slide member has a hole punched through the outer vertical web  12 . When the intermediate slide member  20  and the attached receiver  80  pass over the hole in the outer vertical web, the flanges lodge themselves in the hole in the outer vertical web. As the intermediate slide member  20  is pushed back into the outer slide member  10  the flanges  88  prevent the intermediate slide member from moving.  
         [0065]    The receiver catches the tab  74  on the inner slide member  30 , as the inner slide member  30  reaches a closed position within the intermediate slide member  20 . The inner slide member  30  is forced to slide into the intermediate slide member first because the flanges  88  lock the intermediate slide member in place. Once the inner slide member reaches the closed position of the intermediate slide member, the “c-shaped” tab  72  enters the receiver  80  and pulls the receiver  80  toward the inner slide member  30 . The pulling of the receiver  80  moves the flanges  88  out of the hole in the outer vertical web  12  and allows the intermediate slide member to be closed into the outer slide member.  
         [0066]    Once the “c-shaped” tab  72  of the inner slide member  30  enters the receiver  80 , the button  74  on the “c-shaped tab”  72  engages in the hole  86  of the receiver  80  forming a detent. A significant amount of force is required to move the button  74  out of the hole  86 . This allows staging in reverse, because the drawer opening force will first pull the intermediate slide member  20  out of the outer slide member  10 . Once the intermediate slide member  20  is pulled out of the outer slide member  10 , then a drawer opening force disengages the button  74  from the hole  86  of the receiver  80 . Once the button  74  disengages from the hole  86 , the inner slide member  30  may be extended from the intermediate slide member  20 .  
         [0067]    In order to prevent the intermediate slide member  20  from being pulled all the way out of the outer slide member an additional lock is provided. At a point between the receiver  80  and the first end of the intermediate slide member, the hat section of the intermediate slide member is punched toward the outer slide member  10  to create two tabs  92  extending toward the outer slide member. A portion of the outer vertical web  12  is punched in to create tabs  94  that extend up into the hat section of the intermediate slide member  20 . The tabs  94  of the outer slide member impact the tabs  92  of the intermediate slide member  20  as the intermediate slide member is pulled out of the outer slide member. The tabs prevent the intermediate slide member from being removed from the outer slide member.  
         [0068]    Each of the three slide members contain bends in them to maximize the stiffness and stability of each slide member across its length. The clearance between each of the slide members is designed to be a minimum so that the material thickness of each slide can be maximized for strength, rigidity and wear. The small clearance between each slide member prevents play and interference between slide members.  
         [0069]    In an embodiment of the present invention, each of the slide members is formed through roll forming. Roll forming allows the slides to be inexpensively, and quickly mass produced. Roll forming also provides consistency in the characteristics of the drawer slides.  
         [0070]    Although this invention has been described in certain specific embodiments, many additional modifications and variations will be apparent to those skilled in the art. It is therefore to be understood that this invention may be practiced otherwise and as specifically described. Thus, the present embodiments of the invention should be considered in all aspects as illustrative and not restrictive.

Technology Classification (CPC): 0