The invention relates to a deployment vehicle which has a deployment arm provided with a frontal and a rear roller assembly for deploying a deployable bridge which is provided at its underside with a runner rail configuration defining a track for guiding the roller assemblies. At the ends of the bridge the track has an upwardly open entrance pocket through which the roller assemblies are introduced and guided onto the track.
A deployment vehicle of the above-outlined type and a bridge deployable thereby are disclosed in German Offenlegungsschrift (application published without examination) 36 28 273. The entrance pockets arranged at the bridge ends by means of which the roller assemblies are threaded (guided) onto the track are disclosed in German Offenlegungsschrift 35 17 724.
The roller assemblies have, at each side of the bridge, several serially arranged rollers which are, relative to the deployment arm, pivotal as a unit about a horizontal axis situated at their common mid point. The pivotal axis extends parallel to the axes of the rollers and transversely to the longitudinal axis of the deployment arm.
Upon deployment of the bridge the frontal and rearward roller assemblies engage the runner rails of the bridge and maintain the bridge in the desired position relative to the horizontal. By changing the inclination, the bridge end situated remote from the deployment vehicle may be deposited at the remote (distal) end of the obstacle to be spanned. Upon further lowering of the deployment arm first the rearward roller assembly exits the runner rail of the bridge and thus the bridge which is supported now only by the frontal roller assembly may be, as a result of further lowering of the deployment arm, also deposited at the proximal end of the obstacle to be spanned. Such a bridge deploying (depositing) process is relatively simple and void of problems.
Upon removing the bridge from the obstacle and stowing it on the vehicle, first the frontal roller assembly has to be introduced through the entrance pocket into the runner rails of the bridge. For such a thread-in operation of the second or rearward roller assembly, the deployment arm has to be raised until the runner rails of the bridge and the deployment arm are in a linear alignment with one another. In this position the runner rails and the rollers of the rearward roller assembly have identical heights. Further, the deployment arm has to have such a relative distance from the bridge that the rollers--viewed in the longitudinal direction--are situated in the zone of the entrance pocket.
Provided that sufficient personnel is available, the correct relative position may be observed externally of the vehicle and communicated to the vehicle driver. If, however, a bridge removal and stowing operation has to be carried out exclusively by the driver of the deployment vehicle great difficulties are encountered and, even if such work can be performed at all, it is a very time-consuming process.