EP0604272A1 - Vehicle window regulator with shock absorbing antisqueeze safety device - Google Patents

Abstract

The window-lifter (1) may, for example, be of the twisted-cable type (3) driven by a gear motor unit (2), wound over return pulleys (4,5) and sliding in a guide rail (6); a carriage (8) carrying the window (9) is fixed to the length of the cable which passes through the rail (6); damper elements (11) such as flat metal springs, for example, are fixed to the ends of the guide rail (6) and to the door panel (7), this making it possible to damp out a hard impact against an obstacle encountered by the window (9). <IMAGE>

Description

The present invention relates to a window lifter device for a motor vehicle, comprising a geared motor for driving a kinematic chain at the end of which the window is mounted.

It is known that generally the window regulators are fitted with flexible or flexible elements with a view to absorbing the kinetic energy when the window regulator arrives at the stop, for example as described in EP-A 008 247 ( elastic tabs 21, 22).

However, the characteristics of these energy absorbers do not allow a hard shock to be transformed into a soft shock.

We know that certain standards concerning the safety of car windows can require a test with a hard object. This test consists in putting a hard object in the trajectory of the glass, and in determining if after contact of the glass with the hard object and descent of the latter, the force undergone by the object has not exceeded a certain limit, for example 10 kg. However, some security systems can undergo significantly greater efforts during tests using hard objects. This is due to the rigidity and inertia of the window regulator system and the glass, which is a function of speed. The higher the speed of the window, the greater its inertia.

Theoretically, a completely rigid system that is abruptly stopped by a completely rigid object, develops on the latter an infinite force. It is easily understood that if the system triggers on a soft object at a certain force value, it can, if the test is carried out with a rigid object, greatly exceed this force. Even low inertia, if the speed of translation of the glass is low, can generate efforts very high.

It may therefore prove necessary in certain cases to reduce the rigidity of the system and to absorb the shock.

The object of the invention is precisely to solve this problem in a satisfactory manner, a result which cannot be achieved with the kinetic energy absorbing elements mentioned above.

We also know of documents describing elastic elements in the kinematic chain, suitable for specific functions such as quick fixing (USA4706412, FR-2100148, USA 3281991), backlash (DE-2836032). Furthermore, FR-A 0107531 discloses a window regulator provided with a limit switch spring, incapable of performing any function other than the detection of high end of stroke forces, therefore of the order of 25 at 30 kg, as a side effect.

Finally, GB-A822658 relates to a window regulator in which an elastic system has the essential function of electrical switching between electrical contacts 19 and 20. At the end of the race, or in the event of an obstacle meeting, the spring 35 must not react only to significant efforts, about 20 kg, to allow, in normal use, the retraction of the glass in the seals at closing. As a result, due to its too high stiffness, such a spring cannot provide a function for transforming a hard impact into a soft impact. In addition, if it is desired to replace the spring 35 with a spring capable of ensuring the above transformation, such a spring will be unable to allow the window to be closed by correct entry of the glass into the seals. Indeed, the switching for the reversal of the movement will take place too early, due to the weakness of the spring.

In accordance with the invention, the kinematic chain of the window regulator device comprises at least one flexible force limiting element and shock absorber of a hard impact of the glass against a hard obstacle, this flexible element being adapted to limit the force to approximately 100 Newtons.

This or these anti-pinch safety elements, for example two in number, suitably positioned, may consist of flat metal springs, or else of elastic blocks, in particular of rubber or other material capable of storing energy. of displacement and to restore it.

In a window regulator of the type comprising a cable wound around deflection pulleys and a drum cooperating with the output of the gearmotor, a cable guide rail displaceable in vertical translation relative to a door panel, the cable carrying a glass support trolley, the flexible damping element can be interposed between the rail and the door panel and fixed to the latter.

For each type of window regulator, the invention therefore provides for interposing one or more flexible elements in the kinematic chain in order to absorb the impact of the window against a hard obstacle, thereby constituting an anti-pinch safety device preventing the impact. hard.

Other features and advantages of the invention will appear during the description which follows, given with reference to the accompanying drawings which illustrate several embodiments thereof by way of non-limiting examples.

Figure 1 is a simplified elevational view of a window regulator of the twisted cable type equipped with damping elements according to a first embodiment of the invention.

Figure 2 is a view similar to Fig.1 of a similar window regulator equipped with damping elements according to a second embodiment of the invention.

Figure 3 is a detail view half-section mid-elevation on an enlarged scale, of one of the damping elements of the window lifter of Fig.2.

Figures 4 and 5 are elevation views of window regulator with twisted cable similar to those of Fig.1 to 3, equipped with a damping element according to two other embodiments of the invention.

Figures 6 and 7 are simplified partial elevation views of window regulator of the rack cable type associated with a guide rail, equipped with damping elements according to two other embodiments of the invention.

Figures 8 and 9 are views similar to Fig.6 and 7 showing window racks with rack cable fitted with damping elements according to two other alternative embodiments.

Figures 10 and 11 are simplified elevational views of window regulator of the arm type and toothed sector, equipped with damping elements according to two other embodiments of the invention.

Figures 12 and 13 are simplified elevational views of window regulator of the swing arm type and toothed sector, each equipped with a damping element according to the invention.

FIG. 14 is a graph illustrating the transformation of a hard shock into a soft shock.

The window lifter 1 shown in Fig.1 comprises a geared motor 2 for driving a twisted cable or Bowden cable 3, passing over two pulleys 4, 5 for returning. The strand of cable 3 located between these two pulleys extends along a guide rail 6, mounted movable in translation vertical with respect to a partially shown door panel 7.

The cable 3 carries a carriage 8 on which is mounted a window 9. Two flexible damping elements 11 are interposed between the guide rail 6 and the panel 7 and fixed to them. In the example shown, each element 11 is constituted by a flat metal spring having an appropriate curved configuration, one end of which is fixed by any suitable known means, for example rivets, to a member for connection with the rail 6, such as a tab 12. Its opposite end is fixed, in an appropriate manner and also known per se, to the door panel 7.

Thus a shock of the window 9 against an obstacle placed on its path is transmitted to the carriage 8, then to the rail 6 and to the assembly of the window lifter 1, and absorbed by the flat springs 11. The latter undergo a bending at which corresponds to a displacement of the constituent elements of the window regulator. This movement has been shown only for the pulleys 4 and 5 and the cable 3, which come in position 4a, 5a, 3a shown in phantom, and then return to their initial position under the effect of the elasticity of the springs 11 .

The second embodiment, shown in Fig.2, differs from that of Fig.1 only in that the damping elements are constituted by blocks 13 of elastic material, for example rubber ("silent-blocks") . These blocks 13 are mounted in an appropriate manner, for example threaded on plugs 14 carried by lugs 15 fixed to the rail 6, the end of the plugs 14 opposite the lugs 15 being fixed to the door panel (not shown).

In the embodiment of the window regulator 1 to twisted cable 3 shown in Fig.4, the damping element 16 is interposed between the carriage 8 and a support 17 of the window 9. This damping element 16 is made of any suitable flexible and elastic material such as rubber.

In the variant of FIG. 5, the damping element 18 is constituted by a flat metal spring similar to the springs 11. This damper 18 is fixed to the carriage 8 by one 18a of its two branches, and to the window 9 by its second branch 18b, by any appropriate means known per se.

The window regulator 19 shown in Fig. 6 to 9 is of the rack cable 21 type sliding in a sheath 22 meshing with a pinion 23 for output from the gearmotor 2. A carriage 24 which can slide along a substantially vertical rail 25 of guide, is fixed to the cable 21 and carries the window 9. The damping element 26 is here a flat metal spring, similar to the springs 11, fixed on the one hand to the carriage 24 and on the other hand to the window 9 by means known per se.

In the variant of FIG. 7, the damper consists of a block 27 made of any suitable flexible and elastic material, interposed between the carriage 24 and the window 9.

According to the embodiment of the window regulator 19 shown in FIG. 8, the damping system consists of two flat springs 28, similar to the springs 11. As the latter the springs 28 are mounted on lugs 12 fixed to the rail 25 by one 28a of their branches, while their second branch 18b is fixed to the door panel (not shown).

In the variant of FIG. 9, the damping system consists of two similar elastic blocks 29 to the blocks 13 and mounted in the same way as the latter, between the rail 25 and the door panel.

The window regulator 31 illustrated in FIGS. 10 and 11 is of the type with arm 32 and toothed sector 33 secured to the arm 32, the assembly being mounted oscillating around an axis 34 carried by a fixed plate 35. The toothed sector 33 cooperates with the output pinion 23 of the gearmotor 2. The arm 32 is equipped with several flexible damping elements 36, 4 in number in the example shown, secured to the support (not shown) of the window. The shock absorbers 36 are produced and mounted in the same way as the shock absorber blocks 13 (Fig. 2 and 3).

In the variant of FIG. 11, the four shock absorbers 36 are replaced by 4 flat metal springs 37, fixed by one 37a of their branches to the arm 32, and by the other branch 38a to the support (not shown) of the window.

The window regulator 39 illustrated in FIGS. 12 and 13 is of the arm type 41 secured to a toothed sector 42 by one of its ends, mounted oscillating around an axis 43 and whose opposite end 41a carries the window 9. A damper 44 consisting of a flat spring similar to those of the other embodiments shown, is interposed between the end 41a and the window 9, and fixed to the latter by any suitable means.

In the variant of FIG. 13, the flat spring 44 is replaced by a flexible block 45 interposed between a base 46 secured to the end 41a of the arm 41, and a support 47 of the window 9.

Fig. 14 shows the variation, during an impact as a function of time t, of the force F transmitted by the obstacle. In the case of a hard shock, the curve C1 is an extremely narrow peak, of the order of a millisecond, and of which amplitude A can reach enormous, uncontrollable values.

In the case of a soft shock, the curve C2 sees the force quickly limited to a low value B compared to A, due to its spreading over time t, for example over 10 milliseconds.

The invention is susceptible of various variants, both with regard to the number of damping elements and their geometric configuration. It is in particular obvious that the flat springs can have a very variable geometry, that shown only being provided by way of example. Similarly, any other type of spring may be suitable if its size allows it, for example a helical spring.

Claims (8)

Window-lifter device (1; 19; 31, 39) for a motor vehicle, comprising a geared motor (2) for driving a kinematic chain at the end of which the window (9) is mounted, characterized in that the kinematic chain comprises at least one flexible force-limiting element (11; 13; 16 ...) and absorber of a hard impact of the window against a hard obstacle, this flexible element being adapted to limit the force to approximately 100 Newtons. Device according to claim 1, of the type comprising a twisted cable (3) wound around pulleys (4, 5) for deflection and a drum cooperating with the output of the gearmotor, a rail (6) for guiding the cable displaceable in translation vertical with respect to a door panel (7), the cable carrying a glass support carriage (8), characterized in that the flexible damping element (11; 13) is interposed between the rail and the door panel and attached to these (Fig. 1 and 2). Device according to claim 1, of the type comprising a twisted cable (3) wound around pulleys (4, 5) for deflection and a drum cooperating with the output of the gearmotor, a rail (6) for guiding the cable displaceable in translation vertical with respect to a door panel (7), the cable carrying a carriage (8) supporting the glass, characterized in that the flexible damping element (16) is interposed between the carriage (8) and a support (17 ) of the window (9) (Fig. 4). Device according to claim 1, of the type comprising a rack cable (21) sliding in a sheath (22), meshing with a pinion (23) for output of the gearmotor (2), a carriage (24) carrying the window (9) being fixed to the cable and able to slide along a guide rail (25), characterized in that the flexible element shock absorber (26; 27) is interposed between the carriage and the window (Fig. 7). Device according to claim 1, comprising a rack cable (21) sliding in a sheath (22), meshing with a pinion (23) for output of the gearmotor (2), a carriage (24) carrying the window (9) being fixed to the cable and able to slide along a guide rail (25), characterized in that the flexible damping element (28) is interposed between the guide rail (25) and a support panel and fixed thereto ( Fig. 8). Device according to claim 1, of the type comprising an oscillating arm (32) integral with a toothed sector (33) cooperating with the geared motor (2), this arm being linked to a support for the window (9), characterized in that the flexible damping element (36; 37) is interposed between the arm and the glass support (Fig. 10 and 11). Device according to any one of Claims 1 to 6, characterized in that the flexible damping element is an elastic block (13; 16; 36). Device according to any one of Claims 1 to 7, characterized in that the flexible damping element is a spring, for example a flat metal spring (11; 18; 26; 28; 37).

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