This invention relates to a drive mechanism for at least two windshield wipers of a vehicle, in particular of an automotive vehicle.
From DE-GM 7103702, a drive mechanism for two windshield wipers is known which includes a driving motor with a gear unit. The gear unit is accommodated in a gear casing which is directly linked to the driving motor and which further is designed so that two wiper bearings are worked into the gear casing and the gear casing also receives the driving rods for the two wiper bearings. The gear casing which is a casting or molded part is entirely closed by a cap so that, on principle, the overall drive mechanism features a completely molded case design. Due to its compact design, the essential advantage of such a drive mechanism is the easy handling when being mounted in a vehicle. On the other hand, the gear casing features a relatively complicated shape so that the costs of its manufacture are relatively high. Moreover, the shape of the gear casing invariably determines the points of support of the wiper shafts or rather the distance between the wiper shafts. Thus, a change in the points of support of the wiper shafts or rather in the geometry of the drive mechanism always implies the manufacture of a gear casing of different shape. This known drive mechanism, thus, cannot easily be adapted to varying geometrical conditions of different vehicles so that this drive mechanism, on principle, can be used for the same vehicle, only.
Another drive mechanism for at least two windshield wipers is known from EP 0 409 944 B1. This drive mechanism also includes a driving motor comprising a gear unit which is accommodated in a gear casing which is a casting or molded part and is closed by a cap. The drive mechanism includes two wiper bearings each of which is linked to respectively the gear casing or the cap of the gear casing via a tubular carrier. Each of the tubular carriers is slipped with its opposite ends onto a pivot connected with the wiper bearing and onto a pivot connected with respectively the gear casing or the gear casing cap and is fixed thereon by means of caulking. The essential advantage of this drive mechanism is that it is adaptable in an extremely flexible manner to very different geometrical conditions of different vehicles. On the one hand, such adaptations to the space conditions in the respective vehicle are made by appropriately selecting the length of the carriers which connect the wiper bearings with respectively the gear casing or the gear casing cap. On the other hand, it is possible to effect a further adaptation by bending the carriers or by changing the angle position of the wiper bearings around the longitudinal axis of the carrier. A disadvantage of this drive mechanism is the relatively big number of individual component parts from which this mechanism is assembled. This relatively big number of individual component parts involves increased assembly efforts for manufacturing this mechanism, a heavier weight of the drive mechanism as well as a larger amount of arrangements as regards the individual component parts.
It now is an object of this invention to improve a drive mechanism for at least two windshield wipers so that, on the one hand, it will be relatively easy to adapt it to the space conditions in different vehicles and, on the other hand, to ensure a low-cost manufactureabilty by reducing the required number of component parts.