Suspension assembly for electricity power supply rails

An assembly for suspending electricity power supply rails comprising a cross member (2), bolts (6) or the like for fixing the cross member to a fixed structure (4) in a direction which is perpendicular to the direction of the power supply rails (8), and members for suspending the rails from the cross member. The members for suspending the rails comprise: a series of at least two generally T-shaped half-clamp elements (10) comprising a crossbar (12) and a riser (14) perpendicular to said crossbar (12), with the length of the crossbars corresponding to the spacing between centers of two adjacent power supply rails (8) or to a multiple of the spacing, with the riser (14) of each T shape including a hooking rim (16) on opposite rail engaging faces. A slidable connection is formed between each T-shaped element (10) and the cross member (2) and locking elments (20,22) are provided to lock the endmost T-shaped elements (10e) of the series against translation.

The present invention relates to a suspension assembly for electricity 
power supply rails. 
More precisely, the invention relates to mounting overhead power supply 
rails for moving electric vehicles and devices, the mounting being of the 
type which comprise a suspension support and at least one clamp fixed to 
said support and intended to retain a rail suspended therefrom; said rail 
is usually constituted by a metal section bar which is almost completely 
enclosed in a insulating sheath. 
BACKGROUND OF THE INVENTION 
Clamp mountings of this type are already known and comprise a one-piece 
cross member including a plurality of suspension clamps. In profile each 
clamp is shaped like a horseshoe. The ends of the arms of the horseshoe 
have inwardly directed rims intended for retaining the rail. The cross 
member is fixed to any convenient fixed structure, and specific examples 
of this kind of embodiment are to be found in published German patent 
specification No. 2 453 754. 
This clamp mounting constitutes the closest prior art to the invention in 
that it comprises a cross member which is perpendicular to the rail 
direction and which supports a plurality of clamps or rail-fixing members. 
In addition, other mountings are commonly used which do not include a cross 
member and in which single clamps are directly fixed to a fixed structure 
by screw means constituted by a threaded rod and a nut. 
Some such single clamps are made from one piece of metal or plastic; others 
are made from two or three parts which are assembled by screws or bolts, 
as described in published French patent specification No. 2 185 838. 
Finally, it should be observed that a clamp may be used to fix not just a 
single rail, but also a plurality of rails inserted in a single sheath. 
All the clamp assemblies described above suffer from various drawbacks. 
A first drawback relates to the fixing of the clamp assembly to the fixed 
structure. In the prior art, as mentioned above, such fixing is 
constituted by a threaded rod co-operating with a nut. 
In a mounting which includes a single clamp, it will readily be understood 
that there must be as many fixing points as there are clamps. The time 
taken to mount the clamps is thus rather long. Additionally, the screw 
means used for fixing are generally made of stainless steel and are thus 
rather expensive. Further, other drawbacks result from the difficulty of 
accurately placing fixing holes in a fixed structure. As a result the 
rails are not completely parallel. 
Finally, known clamp mountings are difficult to properly align with the 
rail direction since they tend to pivot about the axis of the fixing rod. 
This results in a twisting phenomenon which causes stress to be applied to 
the power supply rails. 
Another drawback of the prior art concerns the placing and locking of the 
rails themselves in the suspension clamps. 
Some clamps, as explained above, need to be opened in order to insert the 
rail and then closed by means of screws or bolts. In such cases, it takes 
a long time to install a rail because of a very large number of screws 
that need to be tightened. 
When the rails are inserted in clamps having resilient arms, it is true 
that less time is required to install the rails, however the rails are not 
held in a secure manner. That is why this method of fixing can only be 
used with lightweight rails. 
In other cases, the clamps are fitted over an end of the rail and must then 
be slid along the length thereof, i.e. several meters, up to their 
mounting positions; such assembly takes a long time. 
Preferred embodiments of the present invention remedy these various 
drawbacks and propose a clamp mounting assembly which may be rapidly fixed 
to a fixed structure, and whose angular orientation may be easily and 
acurately adjusted; in addition, the fixing cost is not very great, and 
the power supply rails are rapidly installed and are retained in a secure 
manner. 
SUMMARY OF THE INVENTION 
The present invention provides an assembly for suspending electricity power 
supply rails, the assembly comprising: 
a cross member; 
fixing means for fixing said cross member to a fixed structure in a 
direction which is perpendicular to the direction of the power supply 
rails; and 
members for suspending the rails from said cross member; 
the assembly including the improvement whereby said members for suspending 
the rails comprise: 
a series of at least two generally T-shaped half-clamp elements, each 
comprising a crossbar and a riser perpendicular to said crossbar, with the 
crossbar length corresponding to the spacing between centers of adjacent 
power supply rails or to a multiple of said spacing, and with each 
T-shaped element riser including a hooking rim on each of two opposite 
rail-engaging faces; 
means for slidably connecting each T-shaped element to the said cross 
member; and 
means for locking the endmost T-shaped elements in said series against 
translation motion. 
With such an assembly, rail mounting is made considerably easier. Firstly, 
the T-shaped elements are quickly and easily installed on the cross member 
since the length of said cross member is only a few tens of centimeters. 
Subsequently, the rails are quickly installed between the T-shaped 
elements. The T-shaped elements are moved apart and then back together 
again merely by sliding them along a slideway in the cross member. 
Mounting is also made easier since only two fixing screws in total need 
tightening regardless of the number of rails. All these reasons contribute 
to reducing mounting time. 
The spacing between centers of parallel rails is determined by the length 
of the crossbars of the T-shaped elements, and not by the accuracy with 
which the clamps are fixed to the fixed structure. Given that the T-shaped 
elements are easily manufactured to a high degree of accuracy, the spacing 
between rails centers is indeed constant. 
During mounting, the T-shaped elements are freely slidable along the cross 
member. They therefore take up natural positions relative to the rails 
without stressing or deforming the rails. 
In a series of parallel rails, two adjacent rails are separated solely by 
the thickness of the riser of a T-shaped element, in other words, by a 
single wall. The rails can thus readily be placed close to one another and 
the overall size of the assembly is reduced. In addition, since the rails 
are closer to one another, the impedance of a multiphase line is reduced. 
Consequently, in-line voltage drops are low. 
The cross member fixed to a fixed structure is fairly easily oriented in a 
direction which is accurately perpendicular to the rail direction. The 
T-shaped elements which are guided in the slideway of said cross member 
are thus likewise properly positioned relative to the rails. The 
above-mentioned risk of twisting therefore does not exist. 
The cross member may naturally be used directly as a bracket; in this case 
it will be longer and it will be directly fixed to a fixed structure. 
The reduction in the number of fixing screws contributes to reducing the 
cost. Prior art suspension clamps frequently include expensive stainless 
steel fixing means. Construction price is thus reduced. Finally, the gap 
between two half-clamps in accordance with the invention is predetermined, 
thereby predetermining rail clamping and allowing for rail expansion.

DESCRIPTION OF PREFERRED EMBODIMENT 
The mounting of the suspension clamps shown in FIGS. 1 and 2 includes a 
cross member 2. This cross member is fixed to a fixed structure (not 
shown) which may be constituted, for example, by a gantry, a bracket, or 
the ceiling, and it is fixed thereto by an angle iron 4 which constitutes 
a part of said fixed structure. The cross member is fixed to the angle 
iron perpendicularly to the conductor rail direction by means of two bolts 
6. The cross member is provided with side windows 6a level with the bolt 
locations to enable a bolt-tightening tool to pass therethrough. In end 
view (FIG. 2) the cross member has a C-shaped cross section with the slot 
facing downwards. The length of the cross member is determined as a 
function of the number of T-shaped elements which it is intended to 
support, said number being in turn determined by the number of conductor 
rails to be installed. Further, the cross member 2 may serve to support 
additional equipment. The length of the cross member makes it possible to 
have a relatively large space between the fixing holes for the bolts 6, 
thereby making it possible to orient the member perpendicularly to the 
rail direction to a high degree of accuracy with little difficulty. 
As shown in the drawings, and particularly in FIG. 3, each T-shaped element 
comprises a crossbar 12 and a riser 14 which is perpendicular to the 
crossbar 12. In the example described the elements 10 are made of Macrolon 
6030.RTM., which is a rigid polycarbonate. Sliding connection means 
between the element 10 and the cross member 2 are formed on the crossbar 
12. These connection means are constituted by a cap 15 in the form of a 
flat T, made in one piece with the remainder of the element 10, and having 
its arms extending at right angles to the arms of the crossbar 12. The cap 
15 is slidably engaged in the slot of the cross member 2 by means of its 
ends. Given that the cross member is not very long this operation is very 
quick. Two hooking rims 16 are provided at the bottom end of the riser 14 
on either side thereof. The rims 16 are intended to co-operate with a 
conductor rail which could be made of copper but which, in the example 
shown, is constituted by an aluminum core 8a surrounded by an insulating 
sheath 8b of plastic material and having a stainless steel inverted 
V-shaped rubbing strip 8c inserted therein. The insulating sheath 8b 
insulates the conductor from the fixed structure and avoids any risk of 
electrocution. For increased safety, lips provided at the bottom of the 
insulating sheath prevent contact with the conductive portion of the rail. 
A shoe 18 shown diagrammatically in FIG. 1 is engaged between the lips of 
the sheath. The shoe is pressed against the rubbing strip 8c whose V-shape 
ensures proper centering. 
In FIG. 1, four elements 10 are fixed to the cross member 2 in order to 
suspend three rails 8, but more could be provided. For example, six 
conductor rails could be suspended using seven elements. The elements 10 
meet one another and they are pressed against one another. The length of 
the crossbar 12 in the longitudinal direction of the cross member 2 is 
determined as a function of the width of the rails 8 in such a manner that 
when the elements 10 abut against one another, the spacing between the 
rails is properly adjusted. It may be observed that the rails are 
separated solely by the thickness of the risers 14. The rails may thus be 
disposed at a close spacing, e.g. at 50 mm centers, for a current of 1000 
A. 
Only the end elements situated to the left and the right of the series of 
T-shaped elements are locked to the cross member 2. Each of these elements 
are fixed by means of a screw 22 and a plate 20 which acts as a nut and 
which is wider than the slot through the cross member 2. The cap 15 also 
serves to prevent the plate 20 from rotating. 
It may be observed that all of the elements 10 in the series fixed to the 
cross member are identical. The element 10e to the right of FIG. 1 is 
simply reversed prior to being slid onto the cross member. The two 
elements 10 situated between the end elements 10e include respective holes 
passing therethrough to receive respective screws, but the holes are not 
used, which does not matter. It is easier to manufacture only one type of 
element. 
The rails 8 are installed quite simply by moving the elements far enough 
apart to enable a rail to be inserted between risers 14, and then moving 
the elements closer together so as to engage the hooking rims 16 with 
complementary rims 8d provided in the rail sheaths. Before the screws 22 
are tightened, the elements 10 may slide freely along the cross member 2. 
They thus align themselves on the rails 8. Regardless of the number of 
rails, only two screws need to be tightened, thereby saving time. The 
rails are tightened to a predetermined side so as to allow for expansion. 
Naturally, the invention is not limited to the element described, but 
extends to any variant in accordance with the spirit of the invention.