Abstract:
The invention relates to a signaling column with levels which are assembled by a relative pivoting limited in amplitude and interconnected by axially-extending conductors. The body of a level includes a locking bar which extends axially to penetrate an opening in an adjacent level and abuts an edge of the opening on a rotation attempt. The ends of the bar may be displaced and the opening is of such a size as to accommodate the top end of a relevant bar and the bottom end of the bar above.

Description:
BACKGROUND OF THE INVENTION 
     I. Field of the Invention 
     The present invention relates to a signaling column composed of signaling levels, in particular optical signaling levels, which are superposed on one another and fixed to one another by pivoting about the axis of the column. 
     II. Description of Related Art 
     The levels of such a column each have a body which comprises a lateral wall and a cover, and accommodate a signaling member and conductors which are distributed over the periphery of the body and extend parallel to the axis to ensure an electrical connection with the signaling member. Such a column is known, for example, from the document FR 2 128 998. The body comprises means for assembling to the adjacent body by pivoting of limited amplitude and means for interconnecting which ensure, during pivoting, a continuing connection between the different levels. 
     The various levels are assembled by relative pivoting, preferably by a bayonet-type mounting of a body of a level on the body of an underlying level. The mounting is very simple, which means that the dismantling is also very simple. To replace a level or to work on the signaling member of a level, it suffices to pivot the upper level, with the levels which are superposed thereon, in order to dismantle the entire part of the column surmounting the relevant level. It is sometimes desirable to prevent instant dismantling of a level relative to the underlying level, in order to avoid intervention by an unauthorized operator. 
     BRIEF SUMMARY OF THE INVENTION 
     The object of the invention is to lock the levels in a manner which is simple and well adapted to the configuration of a signaling column and which provides the desired protection against untimely dismantling. 
     According to the invention, the body has a lock consisting of a bar which extends axially with a first end accessible by a tool and a second end capable of penetrating an opening of the adjacent body and capable of abutting against an edge of the opening to prevent the pivoting of the body, the bar being displaceable to adopt two axially distinct positions, one a retracted locked position and the other an extended unlocked position. 
     The opening is preferably made in an upper face of the cover which is perpendicular to the axis of the column and the bar preferably has a uniform section over its entire length. The ends of the locking bar may be offset, the opening being dimensioned to accommodate the first end of the relevant bar and the second end of the adjacent bar. 
     The first end of the bar, which is preferably its upper end, may advantageously have an eyelet for operating the tool and may be countersunk relative to the upper surface of the cover in the locked position, the operation being facilitated by the opening having a radially flared shape. 
     The bar may be easily guided in translation in the axial direction of the column by guide surfaces provided in the upper cover and guide elements provided in the lower part of the body. 
     The detailed description which follows illustrates an embodiment given by way of example, with reference to the accompanying drawings, in which: 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  shows an elevation of a signaling column according to the invention, 
         FIG. 2  is a side view of one level of the column, 
         FIG. 3  is a top view of the level of  FIG. 2 , 
         FIG. 4  illustrates, by means of a schematic section according to IV-IV, the interconnection of superposed levels, 
         FIG. 5  shows in schematic perspective one level of the column, 
         FIG. 6  shows schematically the interconnection and the locking of superposed levels, 
         FIGS. 7 &amp; 8  illustrate the locking and respectively the unlocking of two levels of the column. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The signaling column C illustrated in the figures comprises a plurality of superposed signaling levels or modules A. As is seen in  FIG. 1 , the column C extends along a vertical axis X and has four levels A 1 -A 4  fixed to one another, the lowest level A 1  being fixed to a base B which ensures the passage of electrical conductors, the uppermost level A 4  being preferably covered by a lid D. The column may, naturally, have a variable number of levels. One level is mounted onto an underlying level by a bayonet-type movement, with pivoting of limited amplitude, for example at an angle of less than 30°. 
     The body  10  of a level A accommodates a plurality of conductors  20  in the form of beads (see  FIGS. 4 and 6 ). These conductors ensure the supply and transmission of signaling signals toward the various levels, which obviously assumes an interconnection of the ends  20   a ,  20   b  of the homologous conductors belonging to the superposed levels. The body  10  has a cylindrical or prismatic wall  11  with an axis X. The wall  11  is translucent and, for example, colored when the signaling is illuminated, and may be opaque in other cases. The body is provided with an upper cover  12 , of which the upper face  12   a  extends transversely to the axis X. The cover  12  is provided on its periphery with a plurality of inwardly curved passages  13  and, on the inside, insulating contacts  14  adjacent to these passages and designed to receive clip connectors  14   a  which accommodate the ends  20   a ,  20   b  of conductors to be interconnected. On its lower part, opposing the cover, the body  10  has retaining elements  15  for the lower ends  20   b  of the conductors  20  and a lower part  16 . The lower part  16  is provided with shapes  18  for coupling to the upper part  17  of the underlying level, for example of the bayonet type, to cooperate during assembly by pivoting with homologous coupling shapes  19  of the underlying level. The cover  12  bears a signaling member E to which the ends  20   a  of the conductors  20  accommodated in the body of the relevant level are connected. 
     A lock  30  consisting of an axial bar extends inside the body  10 , substantially over the height thereof. The bar  30  is essentially rigid and guided in translation in the direction X by guide surfaces  21  provided in the cover  12  and guide elements  22  provided in the lower part of the body. The bar  30  may, at its upper end  30   a , pass through an opening  23  made in the cover  12 , by being guided in this opening, to project beyond the surface  12   a  of the cover  12 ; the end  30   a  of the bar  30  is not widened and has an eyelet  31  to receive the tip of a tool T. At its lower end  30   b , the bar  30  is guided in the elements  22  and may penetrate an opening of the cover  12  of the underlying level, preferably consisting of the opening  23  already provided in this cover. It is noteworthy that the opening  23  has, on the one hand, an edge  23   a  radially flared towards the outside and, on the other hand, a lateral abutment edge  23   b.    
     The opening  23  is, therefore, dimensioned to accommodate the upper end  30   a  of the bar  30  of the relevant level and the lower end  30   b  of the superposed level. It will be noted that the bars are formed with ends  30   a ,  30   b  which are slightly radially offset, and have a uniformly straight section over their entire length. 
     The locking bar  30  is capable of adopting an upper unlocked position, in which its upper end  30   a  projects relative to the upper surface  12   a  of the cover, and a locked lower position, in which its upper end  30   a  is countersunk relative to the surface  12   a . The maintenance of these positions is partially ensured by the friction against the guide surfaces  21 ,  22 . It is preferable to provide stop elements  32 , such as snap connections or hard points, to maintain the bar in these two positions. 
     The mounting of one level of the column on the underlying level will be explained with reference to  FIGS. 7 and 8 . To be assembled to the underlying level (for example denoted in this case A 1 ), the upper level (for example denoted in this case A 2 ) is initially advanced in the direction X, with axial interlocking of the lower part  16  of A 2  into the upper part  17  of A 1 . Then the operator pivots the body of A 2  about the axis X to obtain the interlocking of the shapes  18  of A 2  onto the shapes  19  of A 1 . During these coupling movements, the locking bar  30  of A 2  is in the upper unlocked position so as not to act on the cover of A 1 . The pivoting is carried out over an angle which depends on the configuration of the elements  13 ,  14   a ,  20 , in this case of the order of the angular extension of the passages  13 . When the pivoting is terminated, the lower ends  20   b  of the conductors  20  of A 2  are inserted in the connectors  14   a  of A 1 . The assembled position is thus confirmed and secured by the operator who lowers the bar  30  of A 2 , manually or by means of the tool T, in guided translation through the opening  13 , the surfaces  21  and the elements  22 . The translation is carried out until the insertion of the end  30   b  of the bar in the opening  23  of the cover of A 1 . As is seen in  FIG. 7 , the end  30   b  of the bar  30  of A 2  is accommodated adjacent to the end  30   a  of the bar  30  of A 1  and thus contributes to the blocking of said bar. 
     When attempting to dismantle A 2 , the locking bar  30  abuts against the lateral edge  23   b  of the opening  23 . To remove the level A 2  it is necessary to unblock its bar  30  by raising by means of the tool T in order to bring the bar into the position indicated in  FIG. 8 . The introduction of T into the eyelet  24  is facilitated by the flared form provided to the external radial edge  23   a  of the opening  23 .