FR3139153A1 - Device for securely blocking the exterior door opening control of motor vehicles - Google Patents

Abstract

The invention relates to a device for securely blocking the exterior handle (2) of a motor vehicle door pivotally mounted on a stirrup (1) while being balanced by a tilting interior counterweight (21), said device comprising a cam (3) intended , on the one hand, to support a first end of a blade (4) under stress while a second end is fixed in the stirrup (1) and, on the other hand, to come into abutment contact by rotation with the counterweight (21) during an impact on the door, characterized in that the characteristic length (L) of said blade (4) between its first (4a) and second ends (4b) corresponds to its natural frequency and is adjustable so as to avoid resonance during an impact. Abstract figure (Fig. 6)

Description

Safety blocking device for the exterior door opening control of motor vehicles

The invention relates, in general, to the field of passive safety of motor vehicles and is more particularly concerned with the means used to protect the occupants of the vehicle in the event of a side impact.

The doors of motor vehicles are generally equipped with locks comprising, respectively, a bolt secured to the door capable of cooperating with a strike plate secured to the bodywork and an opening control comprising an exterior handle.

This exterior handle is pivotally mounted on a bracket, balanced by a tilting interior counterweight and is possibly coupled with a return spring. A pull on this handle releases the bolt from the strike plate and thus ensures the unlocking of the lock before returning to its rest position.

However, vehicle safety standards require that, in the event of a side impact, the doors must remain locked to prevent the risk of ejection of occupants. However, it turns out that through an inertia effect, the kinetic energy resulting from the impact can generate a tensile force on the exterior handle which is then likely to cause the door to open inopportunely.

Among all the solutions implemented today to comply with these security rules, there are systems called"anti-g » (or "inertia lock"), which ensure, in the event of an impact, the blocking of the exterior door opening control handle. Depending on the systems, which are diverse and varied depending on the supplier, this blocking may be reversible or irreversible. The invention relates, more particularly, to anti-g systems with irreversible blocking.

These anti-g systems each have their advantages and disadvantages. Thus, FR3079544_B1 describes a safety device intended to control the blocking of an opening, such as a motor vehicle door. This device includes an inertial member ensuring locking of the exterior handle, in particular, in the event of an accidental side impact.

In addition, there is also an anti-g system comprising a cam mounted in the stirrup which carries the pivoting handle, the latter being balanced by an internal tilting counterweight ensuring its return to the rest position.

This cam supports the end of a blade under constraints fixed in the stirrup and remains inactive in the absence of an impact against the door. In the event of a lateral impact impacting the stirrup and via appropriate mechanical balancing, this cam then immediately comes into contact with the counterweight by rotation. At the same time, the blade is released and, released from its constraints, immobilizes the cam in its counterweight stop position so as to prevent the handle from moving outwards and thus block the door in the closed position, permanently and irreversibly.

However, existing anti-g systems have non-robust mechanical behavior, particularly due to blade vibrations. Indeed, if the blade is subjected to a vibration of too great an amplitude during the impact, it escapes the cam and cannot therefore immobilize it while the latter tends to return to its initial position. In this case, the handle is not blocked during the impact and the door can then open, which is problematic.

However, it turns out that the vibrations to which the blade is subjected are due to a resonance during the shock, which means that the technical problem is linked to the blade's natural frequency.

In this context, the invention consists in proposing a solution which, in its most general aspect, makes it possible to simply resolve the technical problems posed by anti-g systems known to suppress vibrations by modulating the natural frequency of the blade, according to the type of vehicle, and without adding or modifying any part compared to the existing system.

This aim is achieved, according to the invention, by means of a device for safely locking the exterior door handle of motor vehicles pivotally mounted on a bracket while being balanced by a tilting interior counterweight, said device comprising a cam intended, on the one hand, to support a first end of a blade under stress while a second end is fixed in the bracket and, on the other hand, to come into rotational contact with the counterweight during an impact on the door, characterized in that the characteristic length of said blade between its first and second ends corresponds to its natural frequency and is adjustable so as to avoid resonance during a side impact.

According to an advantageous characteristic of the device of the invention, the second end of the blade has at least one orifice intended to receive a fixing member engaged in a bore of the caliper, allowing variable positioning of the blade relative to said cam.

According to a specific variant embodiment of the device of the invention, the stirrup is provided with a series of bores, each allowing the blade fixing member to be fitted.

According to a first variant embodiment, the blade orifice has an oblong profile.

According to a second variant embodiment, the blade has a series of circular profile holes.

According to another embodiment, the blade is positioned parallel to the axis of rotation of the cam.

In an alternative variant, the blade is positioned perpendicular to the axis of rotation of the cam.

Preferably, the characteristic length of the blade between its first and second ends is variable over a range of 4mm.

Another object of the invention is a method of adjusting a safety locking device as defined above, characterized in that the natural frequency of the blade is modulated by adjusting its characteristic length with an offset of +/- 4 mm from its fixing point in the stirrup in the direction of its length.

Yet another object of the invention is a motor vehicle provided with at least one exterior door opening control equipped with a safety locking device as defined above.

Thus, in principle, the invention proposes an improvement of the known blocking devices or anti-g systems which makes it possible to eliminate the vibrations of the blade and which, consequently, guarantees the reliability of this system and compliance with the safety standards in force.

This improvement is essentially based on the possibility given by the invention to modulate the natural frequency of the blade ensuring the blocking of the cam and the blocking of the external handle during the impact, according to the type of vehicle, without adding any part compared to the existing system.

The device and method of the invention thus offer a modular solution for a given unique design and a reference handle present on a majority of vehicles, on the front and rear doors.

This possibility of modulating the characteristic length of the blade can be used in the event of a proven problem during the validation phase of the specifications relating to the behavior of the vehicle with regard to impacts.

Furthermore, the implementation of the modulation method does not generate any need to modify the structure of the external opening control because neither the moving masses of the device, nor the stiffness of the mechanical elements (blade, springs, etc.), nor the contact forces of the anti-g system are modified.

Therefore, the implementation of the invention does not require any redesign of the anti-g system. The traditional opening control can be retained by simply being adapted to a specific assembly and fixing method of the blade which alone allows the technical problem of vibrations posed by previous systems to be solved. The invention therefore does not generate any additional cost.

Therefore, compliance with the specifications regarding the activation of the anti-g system under different accelerations is not impacted and the external opening control blocking device can be used from one vehicle to another by only modifying the blade assembly method.

Other characteristics and advantages of the invention will emerge from reading the description which follows, with reference to the appended figures, for which:

is a cross-sectional view of a traditional embodiment of an exterior opening control for a motor vehicle equipped with a safety locking device in the door closing position.

is a detailed cross-sectional view of the safety locking device of the control of the in the door closing position.

is a detailed top view of the safety locking device for the control of the in the door closing position.

is a cross-sectional detail view of the motor vehicle exterior opening control of the in the locked position during an impact.

is a detailed top view of a preferred embodiment of the safety locking device of the invention in a first blade adjustment position.

is a detailed and top view of the safety locking device of the in a second blade adjustment position.

is a detailed and top view of another embodiment of the safety locking device of the invention in a first blade adjustment position.

For clarity, identical or similar elements are identified by identical reference signs throughout the figures.

Naturally, the modes of implementation of the invention illustrated schematically by the figure presented above and described below are given only as non-limiting examples. It is explicitly provided within the scope of the invention that different modes can be proposed and combined with each other in order to propose others.

The invention relates to the general field of passive safety of motor vehicles and aims at improving the safety locking devices of the vehicle doors activated during a side impact.

For safety and regulatory reasons, the exterior opening controls for motor vehicle doors are now equipped with a safety locking device (also known as an anti-g system) for the lock and, more specifically, its handle.

Traditionally and as illustrated by figures 1 and 2, the external handle 2 is pivotally mounted on a bracket 1 while being balanced by a tilting internal counterweight 21. A pulling maneuver on this handle allows the bolt to be released from the strike plate (not shown) and thus ensures the unlocking of the lock before returning to its rest position thanks to the action of the counterweight 21, possibly coupled to a return spring (not shown).

Such a locking device generally comprises a cam 3 intended to support a first end 4a of a blade 4 placed under stress while a second end 4b of this blade is secured to the stirrup 1 by means of a fixing member 5 (screw, etc.). The first end 4a of the blade 4 is therefore supported on the cam 3.

When the door is struck and rotated about an axis X before any pivoting of the counterweight 21, the cam 3 comes into abutment contact with this counterweight. Thus, the counterweight 21 is immobilized and normally prevents any possible pulling by inertia of the handle 2 likely to occur during the impact.

It is generally provided that, together with the rotation of the cam 3, the blade 4 is released and, released from its constraints, comes to wedge and immobilize the cam in stop contact with the counterweight 21 so as to prevent any subsequent movement of the handle 2 towards the outside and thus to permanently block the door in the closed position, as illustrated by the . For this purpose, the cam has a hook 30 ( ) arranged on the side opposite the side in contact with the counterweight 21 and intended to retain the end 4a of the blade 4.

However, if during the shock, the blade 4 is subjected to a vibration whose amplitude is too great, it escapes from the cam 3 while the latter tends to return to its initial position, as illustrated by the vertical arrow on the . Under these conditions, the counterweight 21 is no longer blocked by the cam 3 and is free again. As a result, the device can no longer ensure the blocking of the handle 2 during the impact.

It has been demonstrated, in the context of the search for a solution to this technical problem which is the basis of the invention, that the vibration of the blade 4 is due to its resonance, during the shock.

Now, for a theoretical model of a bending beam, its frequency is proportional to the inverse of the square of its length. The blade 4 used in the device of the invention also meets this principle.

Therefore, the invention aims to modulate the natural frequency of the blade 4 which depends on its characteristic length L to avoid any vibration and guarantee the blocking of the handle 2 in the event of an impact.

For this purpose, the invention provides means allowing the adjustment of the characteristic length L of the blade 4 (and therefore of its natural frequency) between its first end 4a which rests on the cam 3 and its second end 4b which is fixed in the stirrup 1.

In such conditions, if in a vehicle (or on a door) the blade is subject to a vibration problem likely to generate a safety defect, it will be sufficient to move it in the bracket to change its natural frequency and prevent it from resonating. The locking device installed in another vehicle with the same handle but not presenting a vibration problem will be able to keep the blade in its initial reference configuration.

In practice, a calculation has shown that on a reference blade with a natural frequency of 245Hz, for a length of 29mm, it is sufficient to reduce its characteristic length L (between its two ends 4a, 4b defined above) by 2mm to increase its natural frequency by 40Hz, which is clearly significant.

According to a preferred embodiment, the adjustment of the position of the blade 4 relative to the cam 3 is obtained by making, on the second end 4b of the blade, at least one orifice intended to receive a fixing member 5 engaged in a bore of the caliper.

According to a first variant embodiment of the device of the invention illustrated by FIGS. 5 to 7, the orifice 40 of the blade 4 has an oblong profile. This orifice allows a clearance of +/-2 mm of the characteristic length L of the blade. Preferably, the characteristic length L of the blade between its first end 4a and its second end 4b is variable over a range of 4 mm.

The position adopted by the adjustment of the , corresponds to a characteristic length L of the blade 4 of 29mm, i.e. a natural frequency of 245Hz while the adjustment of the corresponds to a characteristic length L of blade 4 of 27mm or a natural frequency of 238Hz.

According to another variant embodiment of the locking device of the invention (not shown), the stirrup 1 is provided with a series of bores, each allowing the installation of the blade fixing member 5.

According to yet another variant illustrated by figures 5 to 7 and possibly combined with the previous one, the blade 4 has a series of orifices and here a single orifice 41 (complementary to the oblong orifice 40) of circular profile. The blade could then be fixed in one of the positions corresponding to one of these orifices, each of them being associated with a natural frequency.

In the embodiment variant illustrated by figures 5 and 7, the blade is positioned parallel to the axis X of rotation of the cam 3. This variant offers the same contact surface of the blade 4 on the cam 3 in the rest state and also makes it possible to avoid having a hook 30 of specific depth to ensure the retention of the blade and which would then depend on the variable position of the latter. This variant of positioning of the blade could constitute the initial configuration of the exterior opening control of the vehicle. In the variant of the , the blade is positioned here perpendicular to the X axis of rotation of cam 3.

The method of adjusting the safety locking device of the invention is implemented by means of the device described above and illustrated by the figures by modulating the natural frequency of the blade by adjusting its characteristic length L with an offset of +/- 4mm in the direction of its length.

Claims (10)

Device for safely locking the exterior door handle (2) of motor vehicles pivotally mounted on a bracket (1) while being balanced by a tilting interior counterweight (21), said device comprising a cam (3) intended, on the one hand, to support a first end of a blade (4) under stress while a second end is fixed in the bracket (1) and, on the other hand, to come by rotation into abutment contact with the counterweight (21) during an impact on the door, characterized in that the characteristic length (L) of said blade (4) between its first (4a) and second ends (4b) corresponds to its natural frequency and is adjustable so as to avoid resonance during a lateral impact. Device according to claim 1, characterized in that the second end of said blade (4) has at least one orifice (40, 41) intended to receive a fixing member (5) engaged in a bore of the caliper (1) allowing variable positioning of the blade (4) relative to said cam (3). Device according to the preceding claim, characterized in that the stirrup (1) is provided with a series of bores, each allowing the installation of the blade fixing member (5). Device according to one of claims 2 or 3, characterized in that said orifice (40) of the blade (4) has an oblong profile. Device according to one of claims 2 or 3, characterized in that said blade (4) has a series of orifices (41) of circular profile. Device according to one of the preceding claims, characterized in that said blade (4) is positioned parallel to the axis (X) of rotation of the cam (3). Device according to one of claims 1 to 5, characterized in that said blade (4) is positioned perpendicular to the axis (X) of rotation of the cam (3). Device according to one of the preceding claims, characterized in that the characteristic length (L) of said blade (4) between its first (4a) and second (4b) ends is variable over a range of 4 mm. Method for adjusting a safety locking device according to one of the preceding claims, characterized in that the natural frequency of the blade (4) is modulated by adjusting its characteristic length (L) with an offset of +/-4 mm from its fixing point in the stirrup (1) in the direction of its length. Motor vehicle provided with at least one exterior door opening control equipped with a safety locking device according to one of claims 1 to 9.