Abstract:
A ball bearing slide assembly includes a first slide, a second slide, a slide-aiding member, and a positioning member. The first slide is slidably received in the second slide. The slide-aiding member is slidably received between the first and second slides, and comprises a plurality of ball bearings slidably sandwiched between the first and second slides. The slide-aiding member defines a locking hole. The positioning member is mounted to the second slide and forms a resilient cantilever. A positioning block is formed on the resilient cantilever and engages in the locking hole of the slide-aiding member for temporarily locking the slide-aiding member to the second slide, such that the first slide is slidable inward without pushing the slide-aiding member inward. The first slide deforms the cantilever to disengage the positioning block from the locking hole, such that the slide-aiding member is slidable relative to the first and second slides.

Description:
BACKGROUND 
     1. Field of the Invention 
     The present invention relates to ball bearing slide assemblies, and particularly to a ball bearing slide assembly having a positioning device for positioning a slide-aiding member thereof. 
     2. Description of Related Art 
     A slide assembly is usually used to connect and guide two articles that may be moved relative to each other, such as a cabinet and a server or a cupboard and a drawer. A conventional three-section slide assembly generally includes an outer slide, an intermediate slide, and an inner slide. For example, the outer slide may be fixed in a cabinet, the inner slide may be fixed at a side of the server of the cabinet, and the intermediate slide is received in the outer slide to support the inner slide. The inner slide, the intermediate slide, and the outer slide may be coupled with each other, and the inner slide and the intermediate slide may be moved in the longitudinal axial direction of the outer slide. One or more slide-aiding members, each including ball bearings, may be assembled between two neighboring slides, for facilitating the sliding movement of the slides relative to each other. The slide-aiding member can slide between the neighboring slides. However, the inner slide is difficult to be inserted into an unfixed slide-aiding member because the slide-aiding member may be pushed to slide along the intermediate slide by an end of the inner slide. 
     What is desired, therefore, is a slide assembly having a positioning device for its slide-aiding member. 
     SUMMARY 
     An exemplary ball bearing slide assembly includes a first slide, a second slide, a slide-aiding member, and a positioning member. The first slide is slidably received in the second slide. The slide-aiding member is slidably received between the first and second slides, and comprises a plurality of ball bearings slidably sandwiched between the first and second slides for facilitating the sliding movement of the first slide relative to the second slide. A locking hole is defined in the slide-aiding member. The positioning member is mounted to the second slide and forms a resilient cantilever. A positioning block is formed on the resilient cantilever and engages in the locking hole of the slide-aiding member for temporarily locking the slide-aiding member to the second slide such that the first slide is slidable inward along the slide-aiding member without pushing the slide-aiding member inward. The first slide deforms the cantilever of the positioning member to disengage the positioning block of the cantilever from the locking hole of the slide-aiding member such that the slide-aiding member is slidable relative to the first and second slides. 
     Other advantages and novel features of the present invention will become more apparent from the following detailed description of an embodiment when taken in conjunction with the accompanying drawings, in which: 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a partially exploded, isometric view of a ball bearing slide assembly according to an embodiment, the ball bearing slide assembly including a slide-aiding member, a first slide, a second slide, a third slide, and a positioning member; 
         FIG. 2  is an enlarged view of the positioning member of  FIG. 1 , but viewed from another aspect; 
         FIG. 3  is an enlarged view of an end section of the second slide of  FIG. 1 ; 
         FIG. 4  is a partially assembled view of  FIG. 1 , with the first slide being unattached and the slide-aiding member at a locked position; and 
         FIG. 5  is an assembled view of  FIG. 1 , showing the slide-aiding member at an unlocked position. 
     
    
    
     DETAILED DESCRIPTION 
     Referring to  FIG. 1 , in an embodiment, a ball bearing slide assembly includes a slide-aiding member  20 , a first slide  40 , a second slide  60  receiving the first slide  40 , a third slide  70  receiving the second slide  60 , and a positioning member  80  for positioning the slide-aiding member  20  relative to the second slide  60 . 
     Referring also to  FIG. 2 , the positioning member  80  includes a plate portion  86  and two elongated limbs  82 ,  84  respectively bent from two sides of the plate portion  81  in the same direction. The elongated limb  84  of the positioning member  80  is longer than the elongated limb  82  thereof. A stopping flange  860  is perpendicularly bent out from an end of the positioning member  80 . A rectangular opening  862  is defined through the plate portion  86  of the positioning member  80 . A recess  864  is defined in the plate portion  86  of the positioning member  80  adjacent the end of the positioning member  80 . The recess  864  communicates with the opening  862 . A coupling bridge  865  is formed at the other end of the positioning member  80  between the two elongated limbs  82 ,  84 . A fixing hole  866  is defined through the coupling bridge  865 . A pressing tab  820  extends from a free end of the elongated limb  82  of the positioning member  80 , away from the stopping flange  860  of the positioning member  80 . A bottom surface of a distal end of the pressing tab  820  is generally arcuate. A resilient cantilever  840  extends generally perpendicularly from an end portion of the elongated limb  84  of the positioning member  80 , towards the elongated limb  82 . A free end of the resilient cantilever  840  extends slantingly downward. A wedged positioning block  842  is formed at the free end of the resilient cantilever  840 . A wedged surface of the positioning block  842  is opposite to the arcuate bottom surface of the pressing tab  820 . A curved protrusion  844  is formed on the resilient cantilever  840 , offset relative to the positioning block  842  along a direction substantially perpendicularly to the lengthwise direction of the slide-aiding member  20 . 
     The slide-aiding member  20  is sandwiched between the first slide  40  and the second slide  60 . The slide-aiding member  20  has a substantially U-shaped cross-section, and includes a longitudinal web  22 , and two longitudinal arms  24  respectively perpendicularly bent from two lateral edges of the web  22  in the same direction. The web  22  is depressed to form two longitudinal troughs  220  adjacent the two arms  24 . A locking portion  225  including one trough  220  of the web  22 , extends partially from an end of the slide-aiding member  20  along the longitudinal direction of the slide-aiding member  20 . A locking hole  226  is defined in the locking portion  225  and the trough  220  of the web  22 . The positioning block  842  of the positioning member  80  is correspondingly received in the locking hole  226  of the locking portion  225 . A plurality of aligned installing holes is defined in each arm  24 . A plurality of ball bearings  240  is respectively received in the installing holes of the two arms  24  of the slide-aiding member  20 , for facilitating the sliding movement of the first slide  40  relative to the second slide  60 . 
     The first slide  40  has a substantially U-shaped cross-section, and includes a longitudinal web  42 , and two longitudinal arms  44  respectively perpendicularly bent from two lateral edges of the web  42  in the same direction. A release post  420  protrudes from the web  42  adjacent an end thereof. Each arm  44  is depressed towards the opposite arm  44  to form a sliding channel  440  in an outer surface thereof, allowing the ball bearings  240  of the slide-aiding member  20  to slide therein. 
     Referring also to  FIG. 3 , the second slide  60  has a substantially U-shaped cross-section, and includes a longitudinal web  62 , and two longitudinal arms  64  respectively perpendicularly bent from two lateral edges of the web  62  in the same direction. The web  62  and the arms  64  cooperatively define a receiving space for receiving the slide-aiding member  20  and the first slide  40 . The web  62  is depressed outward to form two longitudinal troughs  620  adjacent the two arms  64 . Two notches  626  are respectively defined at two junctions of the two troughs  620  and the web  62  at an end of the web  62 , thereby forming a maintaining tab  627  between the two notches  626 . The maintaining tab  627  is received in the recess  864  of the positioning member  80 . The web  62  is stamped to form a mounting portion  630  adjacent the end thereof, leaving a receiving groove  628  therein. An aligning portion  631  is formed on the web  62  between the receiving groove  628  and the maintaining tab  627 , corresponding the opening  862  of the positioning member  80 . A mounting hole  632  is defined through the mounting portion  630 . A passage  634  is defined through the web  62  between the two troughs  620  thereof, for receiving the resilient cantilever  840  of the positioning member  80 . The passage  634  is spaced at some distance from the receiving groove  628  of the web  62 . Each arm  64  defines an inner channel  640  in an inner surface thereof, and an outer channel  642  in an outer surface thereof. 
     The third slide  70  has a substantially U-shaped cross-section, and includes a longitudinal web  72 , and two longitudinal arms  74  respectively perpendicularly bent from two lateral edges of the web  72  in the same direction. Each arm  74  defines an inner channel in an inner surface thereof. The second slide  60  is slidably received in the third slide  70  by some slide-aiding structure mounted between the inner channels of the two arms  74  of the third slide  70  and the corresponding outer channels  642  of the two arms  64  of the second slide  60 , for facilitating the sliding movement of the second slide  60  relative to the third slide  70 . 
     Referring also to  FIG. 4 , in assembly, a rear end of the slide-aiding member  20  is inserted into a front end of the second slide  60 , between the two arms  64  of the second slide  60 . The front end of the slide-aiding member  20  is pushed rearward, the slide-aiding member  20  is received in and slides forward along the second slide  60 . The ball bearings  240  of the slide-aiding member  20  are received in and slide along the inner channels  640  of the arms  64  of the second slide  60 . 
     The maintaining tab  627  of the second slide  60  is received in the opening  862  of the positioning member  80 . The positioning member  80  is pushed relative to the slide-aiding member  20 , and the other end of the positioning member  80 , having the resilient cantilever  840 , is simultaneously pressed downward. The elongated limbs  82 ,  84  of the positioning member  80  respectively urge the corresponding arms  64  of the second slide  60 , and are snappingly received in the corresponding inner channels  640  of the two arms  64 . The maintaining tab  627  of the second slide  60  is received in the recess  864  of the positioning member  80 , and the stopping flange  860  abuts on the end edge of the second slide  60 . Thus the aligning portion  631  of the second slide  60 , and the coupling bridge  865  and the resilient cantilever  840  of the positioning member  80  are respectively held in the opening  862  of the positioning member  80 , and the receiving groove  628  and the passage  634  of the second slide  60 . The fixing hole  866  of the coupling bridge  865  aligns with the mounting hole  632  of the mounting portion  630 . A rivet  90  extends through the fixing hole  866  of the coupling bridge  865 , and is inserted into the mounting hole  632  of the second slide  60 , the positioning member  80  is then mounted to the second slide  60  by the rivet  90 . 
     The slide-aiding member  20  is slidably pushed toward the positioning member  80 , and the positioning block  842  of the resilient cantilever  840  of the positioning member  80  is pressed downward by the distal end of the locking portion  225  of the slide-aiding member  20 . The resilient cantilever  840  is elastically deformed. The distal end of the locking portion  225  clears the positioning block  842  and enters a gap between the pressing tab  820  of the positioning member  80  and the positioning block  842 . The arcuate bottom surface of the pressing tab  820  facilitates the entering of the distal end of the locking portion  225  in the gap. When the locking hole  226  of the locking portion  225  aligns with the positioning block  842 , the deformed resilient cantilever  840  is restored and the positioning block  842  is locked in the locking hole  226 , such that the slide-aiding member  20  is locked on the second slide  60  by the positioning member  80  and cannot be pulled back along the second slide  60 . During the entering of the distal end of the locking portion  225  into the gap, the distal end of the locking portion  225  is pressed downward by the pressing tab  820  of the positioning member  80  to abut against the corresponding trough  620  of the second slide  60 , thereby preventing the distal end of the locking portion  225  from tilting upward. That prevents damage to the slide-aiding member  20  during the entering of the first slide  40  into the slide-aiding member  20 . 
     Referring also to  FIG. 5 , a front end of the first slide  40  is inserted into the positioning member  80 , between the two limbs  82 ,  84  of the positioning member  80 . The first slide  40  is pushed forward along the positioning member  80 . When the first slide  40  enters into the slide-aiding member  20 , the sliding channels  440  of the arms  44  of the first slide  40  contact the ball bearings  240  of the slide-aiding member  20  to facilitate the movement of the first slide  40 . In the forward movement of the first slide  40  along the second slide  60 , the release post  420  of the first slide  40  abuts against the curved protrusion  844  of the resilient cantilever  840  of the positioning member  80 , and the resilient cantilever  840  is deformed toward the third slide  70 . The positioning block  842  of the cantilever  840  is disengaged from the locking hole  226  of the locking portion  225  of the slide-aiding member  20 . Thus the slide-aiding member  20  is unlocked, and can slide forward along the second slide  60 , together with the first slide  40 . When the locking portion  225  of the slide-aiding member  20  departs from the positioning block  842  of the resilient cantilever  840 , the resilient cantilever  840  is restored. 
     It is to be understood, however, that even though numerous characteristics and advantages of the present invention have been set forth in the foregoing description, together with details of the structure and function of the invention, the disclosure is illustrative only, and changes may be made in detail, especially in matters of shape, size, and arrangement of parts within the principles of the invention to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed.