The present invention relates to a motorized closure device for vehicle doors. More specifically, though not exclusively, the invention relates to a motorized closure device for sliding doors of light vehicles, for example vehicles of the minivan type.

Vehicles intended either for transporting passengers or for transporting goods and provided with lateral sliding doors are known. Such sliding doors usually include a guide allowing the door leaf to slide laterally along the side of a vehicle between a closed position, in which the lateral opening for accessing the vehicle is engaged by the door leaf, and an open position, in which said lateral opening is not engaged by the door leaf.

In some vehicle models, the sliding door leaf is also dragged from the closed position to the open one and vice versa by a motorized mechanism electrically actuated by the driver of the vehicle.

For obvious reasons of interference with the vehicle structure, the sliding door leaf of a vehicle, when moving from the open position to the closed one and vice versa, carries out a trajectory which is given by the combination of a movement with a transverse component and a longitudinal component relative to the longitudinal axis of the vehicle. The transverse component may be either in a direction of approaching the vehicle, when the leaf has to close the lateral opening provided in the vehicle body, or in a direction of moving away from the vehicle, when the door leaf has to open the lateral opening. The longitudinal movement may be either in the direction of approaching the lateral opening, when this has to be closed, or in the direction of moving away from said opening, when this has to be opened. The longitudinal movement of approaching usually takes place towards the front part of the vehicle and the longitudinal movement of moving away takes place towards the rear part, i.e., in most vehicles, when the lateral opening is open, the leaf is located rear said opening, with respect to the forward travel direction of the vehicle.

According to prior art, the transverse translational movement of the door leaf for bringing the door leaf in the configuration in which it closes the lateral opening is obtained partially by means of the leaf dragging mechanism, owing to the configuration of the guides or tracks provided in the vehicle body, and partially by means of a closing device with movable striker arranged either in the front or in the rear along the vertical sides of the lateral opening. More precisely, the transverse movement of the leaf in the last section of the closing stroke towards the lateral opening is caused by a device which forcefully pulls the leaf so as to make it close the lateral opening by overcoming the resistance of the sealing gaskets which usually surround the lateral opening and the door leaf.

WO02103141, WO03018940 and DE4006593 describe motorized devices of the aforementioned type, having a movable striker and adapted to drag a vehicle door leaf for bringing it into a closing configuration.

However, the known devices have some drawbacks mainly associated with the construction complexity and the limited stroke of the movable striker. According to prior art, the door leaf is dragged transversely by means of a movable striker which engages into an abutment solidly connected to the lock of the vehicle door and generally located at the lock. However, the interference between the mobile striker and the abutment in the lock determines a certain wear between the parts and requires reduced tolerances that increase with wear and cause clearances and operating problems, and may even make it impossible to close the door leaf correctly. The aforementioned drawbacks are enhanced by the fact that the movement of the striker occurs along a curvilinear path, said striker being fixed to an oscillating connecting rod.

The main object of the invention is to solve the drawbacks of prior art, in particular those mentioned above.

Another object of the invention is to provide a motorized closure device for vehicle doors, more specifically sliding doors, that is reliable and robust.

A further object of the invention is to provide a motorized closure device that can be easily mounted substantially to any vehicle model and is therefore of practically universal use.

A not least object of the invention is to provide a device of the aforementioned type that can be manufactured at convenient costs and is therefore suitable for large-scale industrial production.

These and other objects are achieved by the motorized closure device as claimed in the appended claims.

The motorized closure device for vehicle doors according to the invention mainly comprises a gear motor ad a movable striker associated with the drive shaft of the gear motor by means of a motion transmitting assembly having a driven shaft. The driven shaft of the motion transmitting assembly preferably receives motion from the drive shaft through a concentric coupling having a male gear, mounted concentrically on the drive shaft, and a female gear, provided with a bore having a shape complementary to the shape of the male gear and mounted concentrically on the driven shaft.

According to the invention, the gear motor is preferably of the kind having a CC electric motor, typically with 12 or 24 V depending on the type of vehicle on which the closure device is to be installed.

The movable striker comprises a pair of parallel rectilinear rods attached, at a first end thereof, to a rear plate and connected to each other at the opposite end by means of a rigid strip. Both the rear plate and the rigid strip are preferably arranged perpendicular to the rods.

The closure device further comprises a fixed guide element, preferably attached to the housing of the gear motor, said guide element being adapted to guide the movable striker between a first, rear position, corresponding to a configuration of closing of the vehicle door, and a second forward position, corresponding to the configuration of opening of the vehicle door. The fixed guide element preferably comprises a proximal plate having at least one supporting ferrule cooperating with a corresponding sliding surface provided in the rear plate of the striker.

Advantageously, according to the invention, the motion transmitting assembly comprises an oscillating lever cooperating with the guide element for causing the movable striker to make a rectilinear movement when shifting from said first to said second position and vice versa. According to the invention, the oscillating lever is hinged to a fixed hinge pin, preferably attached to the housing of the gear motor, and has a reciprocating motion imparted by the rotation of the drive shaft of the gear motor and converted into oscillating motion of the lever preferably by means of a crank mechanism cooperating with a rectilinear slot provided in one of the lever arms.

The guide element may further comprise supporting ferrules cooperating with sliding surfaces provided in corresponding elongated slots provided in the rear movable plate of the striker as well as in the oscillating lever.

Preferably, the guide element further comprises four ferrules, a first ferrule defining a hinge pin for the oscillating lever, a second ferrule defining a guide pin for the oscillating lever and a third and fourth ferrules defining sliding surfaces for the peripheral edge of the window provided in the oscillating lever.

The crank mechanism comprises a crank having a central shaft, axially aligned to the rotation axis of the driven shaft of the motion transmitting assembly, and an eccentric shaft slidable in an elongated slot provided in one of the lever arms.

Still according to the invention, the lever comprises a plate having a window through which the rods of the movable striker pass and which is provided substantially at the center of the plate. The peripheral edge of the window cooperates with the outer surface of at least one of said rods, so that the oscillation of the lever about the hinge pin causes the rectilinear movement of the striker relative to the guide element, thanks to the interference between said peripheral edge and said outer surface of the rods.

According to a preferred embodiment of the invention, the motion transmitting assembly comprises at least one pair of abutments adapted to interfere, during rotation of the drive shaft, with at least one microswitch fixed to the housing of the gear motor and connected to an electric circuit of the vehicle for signaling that the end-stops for the movement of the movable striker in both advancing directions, i.e. opening and closing of the door, have been reached.

Some preferred embodiments of the invention will be described by way of non-limiting example with reference to the annexed figures, in which:

• Fig. 1 is a front view of the closure device according to a preferred embodiment of the invention;
• Fig.2 is a partially exploded sectional view taken along the line B-B of Fig.1;
• Fig.3A is a perspective view of the device of Fig.1 from which the distal plate has been removed;
• Fig.3B is a partially exploded perspective view of the device of Fig.1;
• Fig.4 is an exploded view of the device of Fig. 1;
• Fig.5 is a front view of the device of Fig.1 from which the distal plate has been removed.

Referring to the annexed Figures, a motorized closure device for vehicle doors has been described, indicated as a whole with reference numeral 10. According to the illustrated preferred embodiment of the invention, the device 10 comprises a gear motor 12 and a movable striker 14 associated with the gear motor 12 by means of a motion transmitting assembly 16.

The movable striker 14 comprises a pair of parallel rectilinear rods 18a,18b, attached, at a first end thereof, to a rear plate 20 and connected to each other, at the opposite end, by means of a rigid strip 22. Both the rear plate 20 and the rigid strip 22 are arranged substantially perpendicular to the rods 18a,18b.

The motion transmitting assembly 16 is sandwiched between a pair of plates, namely a proximal plate 24 and a distal plate 26, that are kept at a distance from each other by a series of peripheral columns 28. The distal plate 26 is fixed to the proximal plate 24 by means of screws 30 passing through the distal plate 26 at bores 32 provided therein and engaging in the columns 28 provided between the distal plate 26 and the proximal plate 24. The columns have a hexagonal cross-section and are provided with a threaded axial bore 34, which faces the distal plate 26 and is engaged by the screws 30, and a male threaded shaft 36 which is located at the opposite side and is intended for engaging the columns 28 into the housing 12a of the gear motor 12. In addition, the male threaded shafts 36 of the columns 28 pass through peripheral bores 38 provided in the proximal plate 24 and engage in corresponding threaded seats 40 provided in the housing 12a of the gear motor 12.

The rods 18a,18b of the movable striker 14 protrude from the device 10 through a rectilinear slot 42 provided in the distal plate 26, for engaging in a corresponding abutment of a lock for vehicle door in ways that are known to the person skilled in the art and are therefore not further described.

Referring in particular to the exploded view of Fig. 4, a device 10 obtained according to a preferred embodiment of the invention will be described in greater detail.

The gear motor 12 of the device 10 is a gear motor that is electrically actuated by an electric motor fed through the electric circuit of the vehicle on which the device 10 is installed. The electric power supply of the device 10 takes place by means of conductors 11. The electric motor of the gear motor 12, when energized, causes the rectilinear forward and backward movement of the movable striker 14 by means of the motion transmitting assembly 16. As will be evident from the ensuing description, the motion transmitting assembly 16 is therefore capable of transforming the rotary motion of a primary or drive shaft 44 of the gear motor 12 into a translational motion of the movable striker 14. The drive shaft 44 of the gear shaft 12 protrudes from the housing 12a of the gear motor 12 for imparting a rotary motion to a driven shaft 46 belonging to the motion transmitting assembly 16 by means of a concentric coupling.

The concentric coupling between the drive shaft 44 and the driven shaft 46 is obtained by means of a male gear or pinion 48, which is mounted concentrically on the drive shaft 44 and engages in a female gear 50 which is provided with a bore 52 having a shape complementary to the shape of the male gear 48 and is mounted concentrically on the driven shaft 46.

The motion transmitting assembly 16 comprises an oscillating lever 54, capable of causing the movable striker 14 to make a rectilinear movement between a first rear position, corresponding to a configuration of closing of the vehicle door, and a second forward position, corresponding to the configuration of opening of the vehicle door, and vice versa.

The oscillating lever 54 comprises a corresponding plate 56 in which an actuating arm 54a, a hinging portion 54b provided with a hinging hole 58, and a guide arm 54c are defined. The plate 56 is further provided with a window 60 through which the rods 18a,18b of the movable striker 14 pass and which is provided substantially at the center of the plate 56. The window 60 is provided with a circumferential peripheral edge 62 cooperating with the outer surface of at least one of the rods 18a,18b of the movable striker 14 for causing sliding thereof.

The oscillation of the lever 54 about the hinge axis passing through the bore 58 causes the rectilinear sliding movement of the striker 14 owing to the interference between said peripheral edge 62 and said outer surface of the rods 18a,18b.

The oscillating lever 54 has a reciprocating motion imparted by the rotation of the drive shaft 44 of the gear motor 12. The rotation of the drive shaft 44 is transformed into an oscillating movement of the lever 54 by a crank mechanism 64 cooperating with a rectilinear slot 66 provided in the actuating arm 54a of the lever 54. The crank mechanism 64 comprises a crank 68 having a central rotation axis axially aligned with the rotation axis of the driven shaft 46, and an eccentric bolt 72 which is slidable within the rectilinear slot 66 provided in the actuating arm 54a of the lever 54 and is held by a Seeger ring 72a.

The rectilinear sliding movement of the movable striker 14 and the oscillating movement of the lever 54 are guided by a guide element 74 comprising a plurality of ferrules 76 solidly connected to the proximal plate 24. A first ferrule 76a is housed in the hinging bore 58 and defines a corresponding hinge pin for the oscillating lever 54. This first ferrule 76a does not substantially interfere with the movable striker 14. A second ferrule 76b is housed in an arc-shaped slot 78 passing through the guide arm 54c of the oscillating lever 54. This second ferrule 76b further passes through a first guide slot 80a provided in the rear plate 20 of the movable striker 14. A third ferrule 76c is housed in the window 60 of the plate 56 defining the oscillating lever 54. This third ferrule 76c further passes through a second guide slot 80b provided in the rear plate 20 of the movable striker 14. The first and second guide slots 80a, 80b and, accordingly, the corresponding ferrules 76b,76c, thus define corresponding sliding and guide surfaces for the rectilinear movement of the said striker 14. A fourth ferrule 76d is housed in the window 60 of the plate 56 defining the oscillating lever 54. This fourth ferrule 76d further defines a corresponding sliding surface for an adjoining surface of the peripheral edge of the rear plate 20 of the movable striker 14.

As can be better appreciated from Figure 5, the motion transmitting assembly 16 further comprised a pair of radial abutments 82a,82b defining corresponding abutment surfaces for the oscillating arm 84a of a microswitch 84 during rotation of the driven shaft 46. According to prior art, the interference between the radial abutments 82a,82b and the oscillating arm of the microswitch 84 causes a corresponding end-stop signal in both sliding directions of the striker 14, through an electric circuit connected to said microswitch 84.

In the illustrated embodiment, the device 10 further comprises sliding plates 86a,86b,86c located on the opposite sides of the rear plate 20 and of the plate 54, said sliding plates defining corresponding sliding surfaces for said movable plates 20 and 54 of the device 10.

Frontally, the device 10 comprises a pair of small plates 88,90 provided with corresponding slots 88a,90a through which the rods 18a,18b of the movable striker 14 slide. The small plate 88 is clamped against the distal plate 26, at the slot 42 provided therein, by a pair of screws 92a,92b passing through the small plate 88 at bores provided therein and engage in the ferrules 76a e 76b of the guide element 74, respectively. The screw 92a, therefore, passes through the hinging hole 58 of the oscillating lever 54, and the screw 92b passes through the arc-shaped slot 78 of the plate 56. The small plate 90 is clamped against the small plate 88, at the slot 90a provided therein, by a pair of screws 94a,94b passing through the small plate 90 at bores provided therein and engage in the ferrules 76c and 76d of the guide element 74, respectively. The screws 94a e 94b pass through the window 60 of the plate 56.