Wall bracket and its support

A wall bracket for the support of a shelf, a table or a bench is fastened to a lipped box channel that is vertically positioned with its open slit towards the shelf; it is held in the channel by friction forces only and can be readily moved up and down and held at any desired height of the channel. The bracket end which is inserted into the channel through its slit has a horizontal rectangular top portion smaller than the channel inside, but wider than the slit, and is connected to the bracket body outside the channel by a neck portion of a width narrower than the slit, while the bottom portion is in the shape of a horizontal spike passing into the channel through the said slit and pressed against the channel rear by the load acting on the bracket. The bracket is inserted into, or withdrawn from the channel by turning it until its top portion is vertical and parallel with the slit and can be pushed through it.

BACKGROUND OF THE INVENTION 
Existing shelf supports commonly consist of a set of vertical channels 
fastened to a wall, which are perforated at regular intervals, and sets of 
brackets provided at their inner end with hook-like projections for 
engagement with the perforations in the channels. Different types and 
shapes of perforations and hooks exist in the various appliances 
available, however their common drawback is that the bracket can only be 
fixed at distinct height intervals, dependent on the distance between 
perforations. This again requires very exact alignment of the channels to 
obtain a common height of all perforations in adjoining channels and to 
permit horizontal positioning of the shelves resting on several brackets. 
Still another drawback is the relatively high cost of the channels due to 
the punching operation necessary for providing the--mainly 
rectangular--perforations. 
In view of these disadvantages it is the object of the present invention to 
provide wall brackets which permit the fixation in vertical, 
non-perforated channels at any desired height without use of clamps or 
bolts. Another object is to permit vertical shifting of such bracket in 
upward or downward direction without withdrawing it from engagement with 
the channel supporting it. 
A further object is to permit the manufacture of these brackets from 
extruded metal beams by cutting and punching operations only. 
SUMMARY OF THE INVENTION 
The invention, accordingly, consists of wall brackets adapted to support a 
shelf, a table or the like and bracket-supporting means in the shape of 
lipped box channels of uniform cross section, the said channels being 
vertically positioned with their front, lipped wall facing the said shelf 
or table, while connection of a bracket to a vertical channel is made by 
means of a connector forming an integral part of the bracket body, which 
comprises: 
A top portion in the shape of a horizontal plate forming the end of the 
bracket, symmetrical therewith and of smaller horizontal dimensions than 
the inside dimensions of the channel so as to permit its manual shifting 
inside and along the channel, the front edge of said top portion being 
wider than the slit formed between the channel lips and substantially 
parallel with the inner surface of the said lips, connection between the 
top portion and the bracket body outside the channel being by means of a 
neck portion of a horizontal width smaller than the width of the said 
slit, the said front edge of the top portion being adapted to be biased 
against the lip insides by a vertical load acting on the bracket, 
a bottom portion in spaced relationship with the top portion, symmetrical 
therewith in the shape of a substantially horizontal spike of a width 
smaller than the width of the slit in the channel front and of a length 
commensurate with the depth of the channel, adapted to be inserted into 
the channel through the said slit and to be biased against the rear wall 
of the channel by a vertical load acting on the bracket. 
In a preferred embodiment of the invention the bracket consists of a T-beam 
with its horizontal flange positioned uppermost and its web aligned with 
the slit in the channel. The connector at the inner end of the T-beam is 
formed by two, preferably rectangular recesses cut out on opposite edges 
of the flange leaving a rectangular top portion, and by a cut-out in the 
vertical web at the inner end of the T-beam extending from underneath the 
flange to a line above the bottom edge of the web at a distance therefrom 
defining the upper edge of the spike-shaped portion. The bottom portion is 
provided with a sharpened tip at its end which extends deeper into the 
channel than the inner end of the top portion. 
With a view to serve as a vertical guide, a shallow groove of a width 
somewhat larger than the width of the spike end may be provided on the 
inside of the channel running along the centre of the rear wall thereof. 
In order to prevent inadvertent disengagement of the spike from the channel 
rear wall a lateral tongue may be provided projecting sideways to one side 
of the spike-shaped portion and adapted to engage with the inside of one 
of the lips of the box channel, while the spike end is positioned within 
the said central groove.

DESCRIPTION OF PREFERRED EMBODIMENTS OF THE INVENTION 
FIGS. 1 and 2 of the drawings illustrate the connector of a wall bracket 
II, inserted into a vertical lipped box channel I. The box channel 
comprises a real wall 11, provided with holes 12 for attachment to a wall 
or the like, two side walls 13 and 13' and two front wall lips 14 and 14' 
respectively, which form a slit 15 therebetween. 
The bracket II of a T-section comprises a horizontal flange 21 and a 
vertical web 22. The connector top portion in the shape of a rectangular 
plate 23 is formed out of the flange 21 by two rectanguler recesses 24 and 
24' cut into this flange near the inner end of the bracket leaving a neck 
portion 30, and by a cut-out 25 in the web 23 adjoining the inner end and 
extending from underneath the flange to a line defining the upper edge of 
the spike-shaped bottom portion 26. The latter extends deeper into the box 
channel than the top portion, and its inner end is sharpened to an edge 27 
bearing against the rear wall of the box channel I. The connection between 
the bracket and the box channel and the fixation of the bracket by 
friction forces is depicted in FIG. 2. Herein a vertical load W applied to 
a point on the bracket at a distance L from the centre of the channel, 
creates a moment M=W.multidot.L, which is counteracted by horizontal 
reaction forces R.sub.1 and R.sub.2 pressing the connector against the 
channel walls in opposite directions. The spike end 27 is pressed against 
the rear wall 21 by a force R.sub.1, while the inner edges of the recesses 
24 and 24' press against the inside of the lips 14 and 14' with an equal 
force R.sub.2. These forces are directly proportional to the moment M 
caused by the load W, in inverted ratio to their vertical distance H, as 
expressed by the formula 
EQU R.sub.(1.2) =M/H=W.multidot.L/H. 
the forces R wedge the bracket connector between the front and rear wall of 
the channel and hold it at the chosen height by friction only. Increased 
load will increase the forces R and, accordingly, the resistance to the 
sliding down of the bracket. It is pointed out that a slight deformation 
of the channel walls takes place, especially caused by the spike end 27 
slightly indenting the rear wall, increasingly preventing any tendency to 
slide downward. Shifting of the bracket is performed by somewhat lifting 
the outer bracket end which frees the connector from contact with the 
channel walls, and then raising or lowering the bracket into a new 
position. 
With a view to maintaining the bracket within the centre of the channel it 
is advantageous to provide a guide for the spike end: 
such guide is shown in FIGS. 3, 4 and 5, wherein the inside of the channel 
rear wall is provided with a longitudinal groove 16, 16', either in the 
shape of a recess (16 in FIGS. 3 and 4), or by means of two raised ridges 
17, 17' on both sides of a groove 16' as illustrated in FIG. 6. 
A different embodiment of the bracket is illustrated in FIG. 6, wherein the 
material forming the bracket body is in the shape of an I-beam, comprising 
a top flange 21, a bottom flange 21' and a web 22. The top portion 23' of 
the connector and the spike are similar to those in the embodiment 
illustrated in FIGS. 1 and 2, and are formed by cutting out the portions 
24, 24' and 25. In addition, the bottom flange 21' is cut out on both 
sides adjoining the spike 26 to permit its insertion into the channel 
through the slit 15, except for a short lateral tongue 28 left over on one 
side of the said spike. The combined width of the tongue and the bottom 
portion is less than the width of the channel slit (15) so as to permit 
its passage therethrough. The object of the tongue is to prevent 
inadvertent lifting of the bracket, by that it bears on the inside of one 
of the lips 14 after the spike has been centred. This position is shown in 
FIG. 7. 
Another feature is the provision of a projecting edge 29 at the inner end 
of the top portion 23'. This edge serves to additionally secure the 
bracket in its position by contact with a strip of a resilient material 
18, such as rubber, laid along and attached to the rear wall 11 of the 
channel. FIG. 7 shows a slight indention made in the resilient material by 
this edge; incidentally, a similar indention is made by the spike, whereby 
the friction holding the bracket in position is considerably increased. 
The embodiment illustrated in FIGS. 8 to 10 is characterised by the 
trapezoidal cross-section of the box channel, which comprises a wider rear 
wall 11, a somewhat narrower, lipped front wall 14 and converging side 
walls 13, 13'. The inside of the rear wall is provided with a recessed 
groove 16 similar to that shown in FIG. 5. 
The bracket, of T-section, is similar in most respects to that illustrated 
in FIGS. 1 and 2, the main difference being in the shape of the top 
portion plate 23". This has the configuration of a polygon composed of a 
trapezoidal front portion 31 and a triangular rear portion 32 which meet 
along a common base line 33. The total depth of the plate 23" is 
commensurate with the depth of the channel leaving a small clearance only. 
The lateral edges 34 of the plate 23" are rounded for ready insertion of 
the connector into the channel, as will be explained further on. The 
spiked bottom portion is substantially identical with that illustrated in 
FIGS. 1 and 2. The bracket connector which, of course, may be placed into 
a channel through its open end, may also be inserted through the slit in 
its front wall, by turning the bracket about a right angle, so as to place 
the top portion plate into vertical position, and pushing this plate 
through the slit. While returning the bracket into its normal position it 
is necessary to lift its outer end so as to permit the passage of the 
spike until it faces the said slit. Then the bracket end is lowered again 
and the spike is inserted through the slit until it presses against the 
channel rear wall. 
Returning now to FIG. 4, herein the web 22 is shown to be cut off at a 
slope, not only for esthetic reasons, but for saving of weight, since from 
a mechanical point of view the large cross section is required at the 
inner bracket only. It is obvious that, instead of using extruded material 
to be punched and cut into the desired shape, the bracket may be 
manufactured by other methods, such as die-casting, injection-molding, 
pressing or the like. 
Both the bracket and the channel may be fabricated from any material strong 
enough to support the forces acting on them: a preferred material is 
aluminium in extruded shape, but steel may be employed likewise, if its 
surface is sufficiently corrosion-proof. The shape of the bracket itself 
is not limited to the profiles described in the foregoing, but it may be 
modified to suit various purposes; and it is proposed to make the bracket 
body from pipes or bars of circular or rectangular cross section. However, 
it has been experienced that T-sections are the most suitable because of 
ease of manufacture of the connector portion by simple punching 
operations. 
With reference to FIGS. 3 and 7 showing a tongue 28 projecting sideward 
from the spike 26 as part of an I-beam, it is proposed to provide a 
similar tongue on a bracket fabricated from a T-section, by inserting a 
pin of similar proportions to the tongue into one flank of the bottom 
portion of the web. 
Other modifications and alterations to the bracket and the box channel 
support may be carried out by a person skilled in the art, however without 
deviating from the spirit of the invention and the scope of the following 
claims.