Patent Publication Number: US-2004051015-A1

Title: Fastener for mounting objects on plates

Description:
TECHNICAL FIELD OF THE INVENTION  
       [0001] This invention relates to a fastener intended for mounting objects on plates of the type that comprises two mutually movable tongues, a first one of which is pressable against the bottom side of a plate and the second one is pressable against the top side of the plate.  
       BACKGROUND OF THE INVENTION  
       [0002] Previously known fasteners of the above generally mentioned kind are used for mounting, for instance, table lamps, pencil-sharpeners document holders and the like, on an edge of a table top. In this case, one of the tongues consists of a horizontal, upper branch on a U-shaped clamp, while the second tongue consists of a rotatable washer on the upper end of a screw, which is arranged in a threaded hole in the lower, horizontal branch of the U-clamp. By tightening the screw, the lower tongue or the washer is pressed against the bottom side of the table top, whereby the fastener is reliably fixed on the edge portion of the table top.  
       [0003] By the Swedish design registration MR 65 371, an auxiliary table is previously known for such folding tables which are found in passenger crafts or vehicles, more precisely on the back side of the back of individual passenger armchairs. The object of the above-mentioned auxiliary table is to increase the storage surface of the passenger in connection with consumption of food or drink, preferably by receiving drinking-glasses or the like. The auxiliary table is elongate and has at opposite ends thereof turnable arms, which are articulatedly connected with the auxiliary table and with two fasteners, which are intended to be fastened on opposite side edges of the ordinary, back-carried table. For this purpose, the fasteners include two vertically spaced-apart tongues intended to clutch the table edges. Furthermore, a U-shaped bracket is included in the fasteners in which the lower hinge of the turning arms is hinged. The fastener shown in MR 65 371 is suitable so far that the same is compact and smoothly surrounds the edge of the table. However, a disadvantage of the same is that the two tongues are fixed; this is something that means that the fastener only fits one single thickness of table. However, in practice, the thickness of the foldable storage tables varies most considerably, for instance in aeroplanes and railway-carriages or railroad cars.  
       [0004] The problem with varying thickness of tables would theoretically be solved with such fasteners initially described that include screws for tightening a tongue or washer against the bottom side of the table top. However, such fasteners are unsuitable in connection with foldable storage tables for passenger armchairs together with appurtenant, likewise foldable auxiliary tables, because the screws occupy considerable space in connection with an edge of the table. The screws would simply protrude too far.  
       OBJECTS AND FEATURES OF THE INVENTION  
       [0005] The present invention aims at managing the above-mentioned problems by providing an improved fastener. Therefore, a primary object of the invention is to provide a fastener, which may be attached to differently thick plates, such as storage tables, without the fastener protruding in an annoying way in any direction from an edge portion of the plate. An additional object is to create a fastener that is structurally simple and inexpensive to manufacture and which enables quick and comfortable mounting on a plate.  
       [0006] According to the invention, at least the primary object is attained by the features defined in the characterizing clause of claim 1. Preferred embodiments of the invention are furthermore defined in the dependent claims. 
     
    
    
     BRIEF DESCRIPTION OF THE APPENDED DRAWINGS  
     [0007] In the drawings:  
     [0008]FIG. 1 is a perspective exploded view of the fastener according to the invention, two parts included in the device being shown separated from each other,  
     [0009]FIG. 2 is a front view from behind of the two parts included in the fastener, still in a separated state,  
     [0010]FIG. 3 is a side view of the parts according to FIG. 2, and  
     [0011]FIG. 4 is a front view showing the two parts in a composed state. 
    
    
     DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT OF THE INVENTION  
     [0012] In the drawings,  1  generally designates a first part in which a first tongue  2  is included intended to be pressed against the bottom side of a table top (not shown), while  3  designates a second part having a second tongue  4  intended to be pressed against the top side of the table top. In the first part, two male-like, elastic resilient fingers  5 ,  5 ′ are included having first serrations  6 . Said fingers extend perpendicularly to the tongue  2  and are at the bottom spaced-apart by means of a cylindrical recess  7  with the purpose of facilitating bending of the fingers, more precisely in the direction inwards, towards each other. Suitably, the part  1  is in its entirety made of plastic of such a nature that the fingers, at least partly as a consequence of inherent elasticity of the plastic, may be bent with the upper ends inwards, towards each other from the state shown in FIG. 1, in which said ends are maximally distanced from each other.  
     [0013] Each individual finger  5 ,  5 ′ includes on one hand a web  8 , and on the other hand a bead  9  on which the serration  6  is formed. More precisely, the serrations on the two fingers  5 ,  5 ′ are turned outwards, from each other. In this connection, it should be pointed out that the serrations  6  in the drawings have been illustrated with an exaggerated teeth depth for the sake of clarity. In practice, the serrations may be formed with very shallow teeth or projections.  
     [0014] As may be clearly seen in FIG. 1, the webs  8  are larger than the beads  9 , not only so far that the same are wider than the beads, but also so far that the same are longer than the beads. In the end portions of the webs  8  projecting from the upper ends of the beads, elongate recesses  10  are formed for a tool, the function of which is described closer below.  
     [0015] In the second part  3 , a seat designated  11  is included, which is delimited by two second serrations  12  turned towards each other. The serrations  12  are formed on flanges  13  which together with a rear wall  14  define a through gap  15  (see FIG. 3). In this gap, the web  8  of the fingers  5 ,  5 ′ may be inserted and retained, as is shown in FIG. 4. The gap  15  mouths in an upper opening  16  through which the recesses  10  are accessed from above.  
     [0016] From the lower edge of the vertical wall  14 , a horizontal bottom wall  17  extends that at the outer wall thereof transforms into a vertical, second wall  18 . Together, the walls  14 ,  17 ,  18  form a cross-section-wise U-shaped bracket. In the two vertical walls  14 ,  18 , holes  19  are recessed for a pivot pin (not shown) of a turnable arm of the type that is included in the auxiliary table according to MR 65 371.  
     [0017] In the transition between the tongue  4  and the second wall  14  of the part  3 , a semi-cylindrical flute  20  is formed, which facilitates bending of the tongue  4 . The two tongues  2 ,  4  are advantageously initially inclined in the way that is shown in FIG. 3. More precisely, the tongues converge somewhat in the backward direction from the U-bracket. In this way, the tongues may be resiliently pressed against the top and bottom sides of the table top.  
     [0018] Function and Advantages of the Fastener According to the Invention  
     [0019] Mounting the described fastener on the edge of a table top is carried out by means of the simple measure of pressing up the web  8  of the fingers  5 ,  5 ′ in the gap  15  in the second part  3 . In doing so, the fingers spring away in the direction inwards, towards each other as a consequence of the inherent elasticity of the fingers in combination with the separating recess  7 . The serrations  6  of the first part may in this way be pushed up along the serrations  12  of the second part until the tongues  2 ,  4  come in contact with the two opposite sides of the table top. In this position, further insertion of the fingers is made impossible, the serrations guaranteeing mechanical locking of the parts  1 ,  3  in relation to each other, more precisely by the fact that the serrations engage each other during resilient pressing of the male serrations  6  against the female serrations  12 .  
     [0020] In the assembled state thereof, the described fastener is compact and joins smoothly to the edge portion of the table top in question without other projecting parts than the bracket walls  17 ,  18  (which are located beside the table surface).  
     [0021] If needs arise to dismount the fastener from the appurtenant table top, a pliers tool may be used having two branches which are inserted into the recesses  10  and are pressed together during bending of the two fingers  5 ,  5 ′ inwards towards each other. In this way, the male serrations  6  are released from the engagement with the female serrations  12 .  
     [0022] Feasible Modifications of the Invention  
     [0023] The invention is not solely restricted to the embodiment described above and shown in the drawings. Thus, the invention may also be applied for mounting of other objects than turnable arms of auxiliary tables. Depending on the application area of the fastener according to the invention, the design of the fastener device may be varied in multiple ways within the scope of subsequent claims. In particular, instead of the exemplified U-bracket, other means may be found for connection of the fastener with the object or objects that are to be mounted. Of course, the fastener may also be used on other plates than table tops.