Abstract:
The supporting device for signal transmitters includes a first flat supporting frame, which may preferably be attached in parallel to a ceiling of a tunnel, and a second flat supporting frame adapted to accommodate signal transmitters, wherein the second supporting frame is pivotally connectable to the first supporting frame at a first end of the supporting device via first connecting means, and is detachably fixable to the first supporting frame at a second end of the supporting device via second connecting means.

Description:
RELATED APPLICATION  
       [0001]     This application claims the benefit of DE 20 2004 016 565.1, filed Oct. 26, 2004, the contents of which are incorporated herein.  
       FIELD OF THE INVENTION  
       [0002]     The present invention refers to a supporting device for signal transmitters by the aid of which relatively heavy mechanical and electronic units may be attached particularly to ceilings.  
         [0003]     Supporting devices of this kind have been known since the introduction of mechanically or electro-optical variable message signs and traffic management systems. Usually, supporting devices of this type are arranged perpendicularly at respective masts or bridge piers or laterally on tunnel walls so that the road users may well perceive from a far distance the signal transmitters located within the supporting device.  
       BACKGROUND OF THE INVENTION  
       [0004]     EP 0 917 703 B1 discloses an optical display device, which provides significant advantages with respect to the dimensions, in that the supporting device is aligned substantially in parallel to a predetermined direction of movement of an observer and the display panel is formed of a plurality of spaced display segments arranged successively in the direction of movement in a sequence according to the sign to be displayed, wherein the display segments are arranged substantially in parallel to the surface normal of the supporting device accommodating the display panel or tilted about less than 45° with respect to the surface normal. By this design a very low installation height of the supporting frame is sufficient, since due to the line of vision from the diagonal bottom the impression of a continuous display surface is produced.  
         [0005]     In display devices of this type, the supporting frame has usually been fixedly mounted on the tunnel ceiling, which in the case of initial assembly, in the case of repair work and when exchanging individual display segments leads to significant problems.  
       SUMMARY OF THE INVENTION  
       [0006]     Thus, it is the object of the present invention to provide a supporting device, particularly for variable message signs, which may easily be mounted in any spatial arrangement, in which repair work of the signal transmitters or their exchange can easily be carried out by one single technician in a simple manner without using any tool.  
         [0007]     Accordingly, a supporting device, particularly for variable message signs, is provided, which comprises a first flat supporting fame, which can preferably be attached to a ceiling of a tunnel extending in parallel thereto, furthermore a second flat supporting frame, which is suitable for accommodating signal transmitters, wherein the second supporting frame is pivotally connectable to the first supporting frame at a first end of the supporting device via first connecting means, and is detachably fixable to the first supporting frame at a second end of the supporting device via second connecting means.  
         [0008]     By the two-piece construction of the supporting device and the pivotal arrangement as well as the connection of the two supporting frames that can easily be released again, a supporting device has been created in which a first installation is basically restricted to the attachment of the first supporting frame, whereas the adding of the second supporting frame is extremely simple and can therefore be carried out by one single assembler. Repair and exchange work is also possible without having to remove the entire device from its place, since in a hanging state of the second supporting frame either the signal transmitters can be replaced and exchanged or the entire second supporting frame can be exchanged in a simple manner.  
         [0009]     An especially advantageous form of the pivotal connection is given if the first connecting means comprise two hooks arranged on the second supporting frame as well as two bolt-shaped sections arranged on the first supporting frame, wherein the hooks may pivotally encompass the bolt-shaped sections. Thus, a connection is created that is easily detachable and still ensures a safe connection both in the down-hanging state of the second supporting frame and in the latched state (operating state).  
         [0010]     In order to obtain a slightly inclined position of the second supporting frame within the first supporting frame in the latched position, which is advantageous in the sense of optical perception of the signal transmitters, the second connecting means comprise at least one, preferably two brackets on the second supporting frame, and at least one movable locking means on the first supporting frame for fixing the bracket.  
         [0011]     The bracket advantageous comprises a bolt in the area of its upper end, said bolt being insertable into at least one slot formed in the first supporting frame, wherein a first pivotal locking means for fixing the bracket prevents the bolt from exiting after its insertion into the slot. With all remaining locking means being removed it is thus also ensured that the second supporting frame maybe brought from the latched into the down-hanging position in a simple manner.  
         [0012]     This is particularly simply achieved if the first locking means is formed as a spring-supported locking hook having a substantially V-shaped recess, in which the bolt can simultaneously be inserted when moving into the slot, wherein the web of the V-shaped recess is suitable as a rest surface for the bolt.  
         [0013]     The bracket comprises a head preferably on its upper end, said head having a tapered front end where first and second edges of the head meet. Due to this design it is easily possible to provide a second locking means which is easily operable to cooperate with both edges.  
         [0014]     This is preferably achieved if a roller movable obliquely with respect to the vertical is used as a second locking means, said first edge acting upon the roller when inserting the bracket such that the roller is obliquely lifted.  
         [0015]     In a preferred embodiment, a leaf spring is arranged between the roller and a transverse rail of the first supporting frame, said leaf spring pressing the roller downwards, which causes the roller to be pressed into its locking position and whereby an unlocking of the second supporting frame caused by vibrations is prevented.  
         [0016]     If the second supporting frame is in the completely inserted position, the roller moves obliquely downwards and moves in the operating state of the supporting device to the lower end point of its movement range where the second edge of the head of the bracket is supported on the roller.  
         [0017]     In the sense of suitable kinematics the second edge extends preferably substantially at 45° with respect to vertical.  
         [0018]     The anchoring and guidance of the roller on the first supporting frame is preferably implemented in that the roller is integrated in the first supporting frame on its ends through two bolts that are guided in two longitudinal holes extending substantially at 45° with respect to vertical.  
         [0019]     Further details, features and advantages of the present invention may be derived from the following description with reference to the drawings. 
     
    
     DESCRIPTION OF THE DRAWINGS  
       [0020]      FIG. 1  shows a device according to the invention, in the down-hanging state of the second supporting frame;  
         [0021]      FIG. 2  shows a releasable pivotal connection according to the invention between the first and the second supporting frame;  
         [0022]      FIG. 3  shows an embodiment of the second locking means according to the invention for detachably fastening the second supporting frame in the first supporting frame in a position not yet latched; and  
         [0023]      FIG. 4  shows the view of  FIG. 3  in a latched position. 
     
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS  
       [0024]      FIG. 1  shows a first embodiment of the supporting device  1  according to the invention. The supporting device  1  is composed of a first supporting frame  3  and a second supporting frame  5 . The first supporting frame  3  is durably attached to the subsurface by means of conventional attachment means, wherein the invention is particularly suitable for ceilings of tunnels etc., although the use of the supporting device  1  according to the invention is also conceivable in any other spatial arrangement. The first supporting frame  3  usually comprises two angular rails  7  arranged at a certain spacing to one another, said rails being connected by respective transverse rails. The outer frame generated thereby may be supplemented additionally by a rear wall  11 , although this is not required. The angular rails  7  and the transverse rails  9  together form an accommodation space into which the second supporting frame  5  may be inserted. The second supporting frame  5  has a shape similar to that of the first supporting frame  3 , wherein it is suitable to accommodate rotatable mechanical or electro-optical signal transmitters  13  or similar units. In the present case the signal transmitters  13  shown are lamella-like sections of a variable message sign, which are either formed as mechanically movable prism-like elements or which are equipped with a plurality of light spots so that they entirely form an optical message sign.  
         [0025]     The first and the second supporting frames  3 ,  5  in the down-hanging state of the second supporting frame  5  shown are pivotally connected through first connecting means  15 .  
         [0026]      FIG. 2  shows a section of the supporting device  1  with the first connecting means  15 . The connecting means  15  are composed of two hooks  17  arranged on the longitudinal sides of the second supporting frame  5  as well as two bolt-shaped sections  19 , which are arranged on the first supporting frame  3 . The hooks  17  are shaped such that they encompass the bolt-shaped sections  19  deeply so that the connection also remains in the case of small pivotal movements in the direction towards the opening of the hook  17 . Pivotal movements carried out in the direction of the closed side of the hook  17  are possible beyond the horizontal without a loss of the connection taking place. Due to this connection, the two supporting frames  3 ,  5  may easily be connected to one another and may also be released from one another, and they provide a pivotal connection, which still ensures a very safe handling with the supporting device  1  when the second supporting frame  5  is hanging down.  
         [0027]      FIG. 3  shows the opposite end of the supporting device  1  in a section, wherein the second connecting means  21  for fastening the second supporting frame  5  on the first supporting frame  3  are shown in detail. The second connecting means  21  first of all comprise at least one bracket  23  attached at the second supporting frame  5 , wherein said bracket can also be formed as a swiveling bracket. The bracket  23  substantially has an angular shape, wherein the longer leg  25  extends upwards and the shorter leg  27  substantially extends horizontally and is attached at its end rotatably or fixedly to the second supporting frame  5 . The longer leg  25  has on its end a head  29 , which has a tapered front end  31  where a first, upper edge  33  and a second, lower edge  35  converge. The lower edge  35  is substantially straight and extends approximately at 45° to the vertical, whereas the upper edge  33  may have a rounded shape.  
         [0028]     In the area of the head  29  an outwardly projecting bolt  37  is arranged. When inserting the second supporting frame  5  into the first supporting frame  3  this bolt  37  extends in a slot  39  which is formed in a vertically arranged angular leg of the first supporting frame  3  and which extends substantially perpendicular in same. To fix the bracket  23 , a first locking means  41  and a second locking means  43  are arranged on the first supporting frame  3 . Each one of the two means  41 ,  43  would already be sufficient for a detachable fastening of the second supporting frame  5  to the first supporting frame  3 . However, additional advantages in operation and with respect to safety aspects result by the combined use of the two mechanisms.  
         [0029]     The first locking means  41  is formed as a spring-supported locking hook  45  which has a substantially V-shaped recess  47  tilted at 90°. When inserting the bolt  37  into the slot  39 , the bolt  37  is at the same time inserted into the recess  47 , and the locking hook  45  performs a lateral compensation movement according to the tilted V-shape of the recess  47 . As soon as the bolt  37  has passed beyond the apex of the “V”, it is prevented from returning in that the spring-supported locking hook  45  swings back into its starting position and the bolt  37  is prevented from performing a further movement downwards by the web  49  of the V-shaped recess  47 . The web  49  preferably has a horizontal edge so that the bolt  37  can safely rest thereon.  
         [0030]     As a second locking means  43  a movable roller  51  extending in the transverse direction of the first supporting frame  3  may be provided, which is integrated in the first supporting frame  3  on its outer ends through bolts  53  that are guided in two oblong holes  55 . The oblong holes  55  always extend at approx. 45° with respect to the vertical so that an obliquely guided upward and downward movement of the roller  51  is enabled.  
         [0031]     When inserting the second supporting frame  5  into the first supporting frame  3 , the bolt  37  of the bracket  23  is guided in the slot  39  and thus the head  29  of the bracket  23  also performs a defined upward movement. During this upward movement, the upper edge  33  of the head  29  gets into contact with the roller  51  and pushes same along the oblong holes  55  obliquely upwards until the front acute end  31  of the head  29  is located above the height level of the longitudinal axis of the roller  51 . Thereupon, the roller  51  again slides in the oblong holes  55  obliquely downwards into the initial state, and when the technician releases the second supporting frame  5  the oblique lower edge  35  of the head  29  rests on the roller  51  from above and is prevented by same from a downwardly directed movement.  
         [0032]     In this locked state shown in  FIG. 4 , the bracket  23  is in a higher position than in the locked state with respect to the locking hook  45 . Thus, the release of the second supporting frame  5  from the first supporting frame  3  may be implemented in an especially simple manner in that the technician moves the roller  51  transversely upwards whereby the acute end  31  of the bracket  23  becomes free and the bracket  23  therefore falls downwards until the bolt  37  is stopped by the web  49  of the locking hook  45 . By operating the locking hook  45  from this position it can easily be succeeded in fully unlocking the bracket  23  and moving the second supporting frame  5  into the down-hanging position according to  FIG. 1 . In this position repair or exchange works can be carried out simply.  
         [0033]     The double locking means  41 ,  43  serve besides the higher safety also for the simple and safe release of the fastening connection between the second supporting frame  5  and the first supporting frame  3 . In order to prevent the unlocking of the second supporting frame  5  by vibration and to also enhance the downward sliding power of the roller  51  in the oblong holes  55 , a leaf spring (not shown) may additionally be arranged between the roller  51  and the respective transverse rail  9  of the first supporting frame  3  which presses the roller  51  downwards,  
         [0034]     It is clear that the principle according to the invention can also be realized by geometric embodiments deviating from this. Different connecting means between the roller  51  and the first supporting frame  3  may for instance be chosen, and the geometric design of the locking hook  45  and of the bracket  23  is not limited to the embodiment shown.  
         [0035]     Thus, the supporting device according to the invention enables a simple assembly and repair and a quick exchange of parts without great effort in any spatial orientation.