Patent Document

BACKGROUND OF THE INVENTION  
         [0001]    The present invention is directed generally to latched drawer slides, and more specifically to a latch for maintaining a drawer slide in a preset position.  
           [0002]    Drawer slides are used in a variety of applications, including business furniture, kitchen drawers, electronic racks, and copiers. One type of drawer slide is a telescopic drawer slide. Telescopic drawer slides often comprise two, three, four, or more telescoping members. The shape of a drawer slide, and the individual members, are determined by the design. The slides can be frictional, with members rubbing against each other with a lubricant, or a slide assembly may include roller or ball bearings for easier movement. The members in such assemblies tend to be C-shaped in nature.  
           [0003]    Methods have been devised for stopping drawer slides from fully opening and for locking drawer slides in their open position. Such methods have at least one significant shortcoming. This shortcoming is that one must place a finger in close proximity to the juncture of the moving members. In such a position, the finger is subject to possible pinching or cutting.  
           [0004]    Consequently, a low cost mechanism is required that will allow activation of latches while keeping fingers and hands away from areas of possible harm.  
         BRIEF SUMMARY OF THE INVENTION  
         [0005]    The present invention therefore provides a release mechanism for drawer slide latches. In one embodiment the present invention provides a remote release mechanism for drawer slide latches. In one embodiment the release mechanism comprises a telescopic drawer slide having a first member slidably coupled to a second member. A latch member is affixed to the first member, the latch member engaging a tab on the second member, and a mechanism translatably coupled to the first member, the mechanism translatable to press against the latch. In one embodiment the release mechanism for a slide further comprises a latch member pivotably coupled to the first member, and the mechanism causes the latch member to pivot when translated to press against the latch.  
           [0006]    In a further embodiment the invention comprises a drawer slide with a lock feature. The drawer slide comprises a first slide member and a second slide member slidably coupled to the first slide member. The invention further comprises a lever having a stop surface, the lever coupled to the first slide member, and a tab on the second slide member. The tab engages the stop surface when a first slide member and a second slide member are in a defined position with respect to each other. The invention further comprises means for disengaging the stop surface from the tab. In a further embodiment the invention further comprises means for biasing the means for disengaging the stop surface from the tab away from the lever.  
           [0007]    In a further embodiment, the invention comprises, in a drawer slide with a locking disconnect latch, the drawer slide being of a telescopic type with at least two along a slide slidably coupled. A first slide is nested within a second slide, with the first slide extendable from a retracted position substantially nested within the second slide to an extended position extending from the second slide. In such an embodiment the locking disconnect latch comprises a lever pivotably mounted to the first slide, the lever including a cutout portion forming a stop surface, and means for biasing the lever, the means for biasing the lever being coupled to the first slide.  
           [0008]    These and other aspects of the present inventionn will be more fully understood through examination of the attached figures viewed in conjunction with the following description. 
       
    
    
     DESCRIPTION OF DRAWINGS  
       [0009]    [0009]FIG. 1 is an isometric side view of a three member drawer slide with latch.  
         [0010]    [0010]FIG. 2 is an isometric view of one embodiment of the present invention installed on a slide member with a rotating latch.  
         [0011]    [0011]FIG. 3 is an isometric view of one embodiment of the present invention installed on a slide member with a spring latch.  
         [0012]    [0012]FIG. 4 is an end view of a slide member with a mechanism of the present invention installed thereon.  
         [0013]    [0013]FIG. 5 is a planar side view of an alternative latch and mechanism of the present invention. 
     
    
     DETAILED DESCRIPTION  
       [0014]    A mechanism is provided that attaches to a member of a slide assembly. The mechanism is used to bias or cam a latch, with the latch being used to maintain at least two members of a drawer slide in a predefined position. For purposes of clarity, the mechanism is illustrated in a typical three member ball bearing slide application with C-shaped members. The mechanism is adaptable to slide assemblies with more members, or with fewer members.  
         [0015]    As illustrated in FIG. 1, a drawer slide assembly  10  comprising an inner, or drawer, member  19  is slidably coupled to an intermediate member  13 . The intermediate member in turn is slidably connected to an outer member  18 . As illustrated, the slides are formed of elongate longitudinal webs having bearing raceways along their longitudinal margins. The slides are slidably coupled by bearings riding in the raceways. In alternative embodiments the slides are friction slides, slidably coupled by contact points along the slides.  
         [0016]    As illustrated, the inner member  10  includes a latch. The latch, in the embodiment described, includes an elongate member  15  pivotably or rotatably coupled near one end of the inner slide member. The latch includes stop surfaces, which are part of a cutout of the elongate member. The stop surfaces are adapted to engage, or lock, onto a lanced out tab  16  formed in the intermediate member  13 . Release of the slide for closure or disconnecting for service is accomplished by rotating latch  15  away from tab  16 .  
         [0017]    Often the elongate member, or latch member, is mounted near what is the rear of the inner slide member so that the latch member is approximate a forward end of the intermediate slide member when the inner slide member is extended from the intermediate slide member. The lanced out tab, therefore, is placed near the forward end of the intermediate member, with the latch locking the slides in the open position.  
         [0018]    To increase the safety in releasing the latch, a mechanism  20  is attached to a drawer member  19  with shoulder rivets  21 , as illustrated in FIG. 2. The shoulder rivets extend through linear slots in the mechanism. The use of shoulder rivets allows the mechanism to be moved, or translated, along the length of the inner slide member. Pushing the mechanism, particularly along a tab  28  at a forward end of the mechanism, causes an end  23  of the mechanism to press against a leading edge  24  of a latch member  15 . This results in rotation of the latch member such that stop surfaces formed by a cutout  25  in the latch member do not engage a tab of the intermediate slide member (not shown in FIG. 2), thereby releasing the latch member. Depending upon the shape of the cutout, or notch, in the latch member, and the amount of push applied, the slide can be closed or disconnected.  
         [0019]    For example, in one embodiment a forward stop surface, which restricts rearward movement of the slide member, clears the tab prior to a rearward stop surface, which restricts forward movement of the slide member. Accordingly, greater pivoting of the latch is required to allow the inner member to move forward and disconnect from the other slide members.  
         [0020]    Further, as illustrated in FIG. 2, a spring  22  acts to oppose the pushing action and secure the latch while returning the mechanism to its original position. In addition, in one embodiment, a register  27  on the mechanism is used to prevent sufficient rotation of the latch through application of the mechanism to allow for sufficient rotation of the latch to allow for disconnect. Instead, sufficient rotation for disconnect is accomplished by hand.  
         [0021]    A mechanism  30  can also be designed to activate a spring type latch arm  31  mounted on an intermediate member  39 , as shown in FIG. 3. As illustrated in FIG. 3, an end of the mechanism  32  is shaped to cooperate with a spring latch  31  on its leading edge  34  to flatten the spring latch towards the web of the slide member. Such motion results in cutouts of the latch being freed of contact with a tab extending towards the web from another slide member. The spring latch pushes the mechanism back to its original position. The simplicity of the design results in a low cost. Return action of the release mechanism is provided by the spring qualities of the latch. However, for heavy duty applications or to satisfy a user&#39;s preference, a spring  35  can be installed between the mechanism  30  and a lanced tab  36  on the member  19 . Beneficially, the spring type latch includes both upper  37  and lower  38  cutouts, thereby allowing the latch and slide member to be used with both right and left hand slides; i.e., the slide member is unhanded.  
         [0022]    [0022]FIG. 5 illustrates an alternative embodiment in which the mechanism is pulled in order to achieve much of the effect as is accomplished with respect to the embodiment in FIG. 3. In the embodiment of FIG. 5, a latch arm  51 , coupled to a drawer slide member web by rivets  58 , is adjusted through use of a mechanism  52 . The latch includes a cutout  53  which is adapted to receive a tab extending from another slide member. The latch is bent, as in the embodiment of FIG. 3, such that the portion of the latch including the cutout extends towards the opposing slide member. The latch also includes a second cutout  55 . The second cutout is adapted to receive a protrusion  59  extending from the mechanism. Moreover, in one embodiment, the mechanism also includes a mechanism cutout  57  which is adapted to receive a protrusion extending from the latch.  
         [0023]    Pulling a mechanism tab (not shown) on the mechanism effectively lengthens the latch arm and thereby cause the latch arm to flatten against the slide member. This movement of the latch arm results in the cutout being removed or biased away from the tab. Thus, in alternative embodiments, pulling of the mechanism away from the latch is used to disconnect the latch from a tab extending from another slide member.  
         [0024]    The mechanism in various embodiments is thin. Typical construction can be from  16  gauge steel. If the member size permits, the mechanism can be designed to fit inside the shape of the member allowing elimination of rivets. In an exemplary embodiment, the mechanism  20  fits slidably inside the radius  41  of the drawer member  19  as shown in FIG. 4. As indicated, the mechanism is held in place against a web of the slide member through contact with the interior of a bend in the drawer slide forming a bearing raceway. Thus, in one aspect the mechanism is placed in position, with the bearing raceways thereafter formed as part of a bending operation. Although illustrated in FIG. 4 as not impinging on the bearing raceway, in other embodiments the mechanism does so, but outside of the travel path of the bearings. Moreover, the mechanism is not itself bound by interaction between slide members, as is the latch, thereby increasing ease of operation.  
         [0025]    Those skilled in the art will recognize that changes in the shape of the release mechanism and latch can result in different actions. One shape may create release action by pushing, while another cause release by pulling. More refined shapes could allow a release action for closing, but prevent disconnecting of the slide.  
         [0026]    Furthermore, although illustrated in a ball bearing slide, the release device will work equally well in slides with roller bearings or of the friction type, with no bearings at all. Construction of the slides and release can be from metal, plastic, or other similar materials suitable to the function.  
         [0027]    Accordingly, the present invention provides a mechanism for use with drawer slide latches. Although this invention has been described in certain specific embodiment, many additional modifications and variations would be apparent to those skilled in the art. It is therefore to be understood that this invention maybe practiced otherwise than as specifically described. Thus, the present embodiments of the invention should be considered as illustrative and not restrictive, the scope of the invention to be indicated by the claims and their equivalents supported by this application rather than the foregoing description.

Technology Category: 1