FR2884191A1 - Motor vehicle`s seat articulation mechanism, has rising step in shape of wedge pushing back locking step in locking position when rising step is in active position and unlocking position when rising step is in pitch position - Google Patents

Abstract

The mechanism has a pair of rigid plates (7, 8) mounted pivotally with respect to each other around a rotation axis (Y). A locking step (40) is mounted movably on the plate (8) between a locking position, where a tooth of the step is in contact with a tooth of the plate (7) and unlocking position, where the locking step does not interfere with the tooth of the plate (7). A rising step (19) in the shape of a wedge pushes back the locking step into locking position when the rising step is in active position and unlocking position when the rising step is in pitch position.

Description

Hinge mechanism for a vehicle seat and seat equipped with such

mechanism.

  The present invention relates to articulation mechanisms for vehicle seats and seats equipped with such mechanisms.

  More particularly, the invention relates to a hinge mechanism for a vehicle seat comprising: - first and second rigid armatures pivotally mounted relative to each other about an axis of rotation, - a toothing integral with the first armature and forming at least one circular arc centered on the axis of rotation, - at least one blocking groove which has teeth and which is slidably mounted between first and second guides belonging to the second armature between a on the other hand, a locked position where the toothing of the blocking grain is engaged with the toothing of the first frame to immobilize the first and second frames relative to each other, and secondly, an unlocked position where said blocking grain does not interfere with the toothing of the first frame, said blocking grain having first and second side edges and at least the first side edge delimiting, with the first guide, a wedge-shaped free space, a wedge-shaped seed push-piece penetrating said free space and movably mounted on the second reinforcement between on the one hand, an active position where said push-rod repels the blocking grain in the locked position, and secondly, an erased position where said seed driver allows the blocking grain to move into the unlocked position, - and a control cam adapted to selectively be pushing the seed elevator into the active position or allow the seed elevator to move to the erased position.

  Document FR-A-2 205 132 describes an example of such a hinge mechanism.

  The present invention aims to improve the articulation mechanisms of this type, in particular to improve the mechanical strength without substantially increase the clearances between the first and second frames in the locked position.

  For this purpose, according to the invention, a hinge mechanism of the kind in question is characterized: - in that it further comprises at least one locking grain which has a toothing and which is mounted movably on the second frame between on the one hand, a locked position where the toothing of the locking grain engages with the toothing of the first frame, and secondly, an unlocked position where said locking pin does not interfere with the toothing of the first reinforcement, in that the grain elevator is adapted to push the locking grain into the locked position when said grain elevator is in the active position, and said grain elevator being adapted to allow the locking grain to move in the position unlocked when said seed elevator is in the erased position.

  Thanks to these provisions, the hinge mechanism comprises more grains cooperating with the toothing of the first frame, without requiring more grain pusher, and without generating play between the first and second frames in the locked position.

  In preferred embodiments of the invention, one or both of the following provisions may be furthermore used: the teeth of the blocking grain have a lower radius of curvature than the teeth; the first frame; the toothing of the locking grain has a radius of curvature substantially equal to the radius of curvature of the toothing of the first armature; the grain elevator has first and second convergent wedge-shaped edges each having at least one convex portion, the convex portion of the first edge of the seed-shoot contacting the first guide and the convex portion of the second edge of the seed shoot contacting the first side edge of the blocking grain when said seed elevator is in the active position; - The first guide has a support portion is convex or rectilinear, against which comes into contact with the convex portion of the first edge of the grain elevator when said grain elevator is in the active position; - The first lateral edge of the blocking grain has a support portion is convex or rectilinear, against which comes into contact with the convex portion of the second edge of the grain elevator when said grain elevator is in the active position; - The convex portion of the second edge of the grain elevator is extended towards the axis of rotation by a concave portion having a concavity facing the blocking grain; the blocking grain has a convex rear edge facing the concave portion of the second edge of the grain elevator; the second lateral edge of the blocking grain is rectilinear and comes into contact with a rectilinear portion belonging to the second guide when said blocking grain is in the locked position; the first edge of the grain elevator comprises a rear portion arranged to bear against the locking grain, opposite the toothing of said locking grain; the grain elevator comprises a cam edge opposite the first and second edges of said grain elevator, and the control cam is arranged to come into contact with said cam edge to push the grain elevator radially towards the outside in active position; the locking mechanism comprises several grain pushers each cooperating with a blocking grain and a locking grain.

  Moreover, the invention also relates to a vehicle seat comprising a seat and a backrest interconnected by at least one articulation mechanism as defined above.

  Other features and advantages of the invention will become apparent from the following description of one of its embodiments, given by way of non-limiting example, with reference to the accompanying drawings.

  In the drawings: FIG. 1 is a schematic view of a vehicle seat comprising a hinge mechanism according to the invention, FIG. 2 is an axial sectional view of an embodiment of the hinge mechanism. fitted to the seat of FIG. 1, in the locked position of this mechanism, the section being taken along the line AA of FIG. 3, - FIGS. 3 and 4 are sectional views respectively along the lines BB and CC of FIG. Fig. 5 is an enlarged partial view of Fig. 3; Figs. 6 and 7 are views similar to Figs. 3 and 4, respectively, showing the hinge mechanism in its unlocked position, and Figs. and 9 are views similar respectively to Figures 3 and 4, showing the hinge mechanism in an intermediate position between its unlocked position and its locked position.

  In the different figures, the same references designate identical or similar elements.

  As shown schematically in Figure 1, the invention relates to a vehicle seat 1, including a front seat of a motor vehicle, which comprises a backrest 2 mounted on a seat 3, itself attached to the floor 4 of the vehicle. The backrest 2 is pivotally mounted on the seat around a transverse horizontal axis Y, by means of at least one hinge mechanism 5 controlled by a control handle 6 or the like.

  As represented in FIGS. 2 to 4, the articulation mechanism 5 comprises: a first armature 7, for example a disk-shaped metal flange perpendicular to the axis of rotation Y, which in this case is movable and secured with the rigid frame of the backrest 2, - a second frame 8, for example a disk-shaped metal flange parallel to the first frame, which in this case is fixed and secured to the frame of the seat 3, - a metal ring 9 (or any other means of connection between the two plates 7, 8) which is crimped around the periphery of the first and second plates allowing relative rotation between the two plates and delimiting with them a closed circular case - And a locking device 10 which is contained in this housing and which is adapted to immobilize the two frames 7, 8 as the handle 6 is not actuated.

  The locking device 10 comprises a control cam 11 which can be metallic and which is pivotally mounted about the axis Y. This cam 11 can be secured to the handle 6. The cam 11 may for example have an outer edge 12 of generally circular shape from which protrudes at least one cam edge 13 (in the example shown in the drawings, the cam 11 has three projecting cam edges 13 distributed at 120 from each other).

  The cam 11 is resiliently urged in an angular locking direction V (FIGS. 3 and 4), for example by at least one spiral spring 16 which can notably be housed in a bowl 15 formed in the second armature 8 and acting for example on a control shaft 17 integral with the cam 11 (see Figure 2).

  Each of the cam edges 13 extends diagonally radially outwardly in an unlocking angular direction D opposite to the direction V, and acts against a complementary cam edge 18 belonging to a rigid grain pusher 19 made for example of metal.

  As shown in more detail in FIG. 5, the grain elevator 19 has a generally triangular general shape having first and second radially outwardly wedge-like edges 20, 21 opposite the cam edge 18 .

  More specifically, the first edge 20 of the grain elevator may have, for example over its entire length, a convex shape, with for example a constant radius of curvature of the order of 10 to 30 cm. The second edge 21, meanwhile, comprises a front portion 22 of convex shape, with for example a radius of curvature of the order of 5 to 20 cm, this convex front portion being extended, radially inwards, by a concave rear part 23.

  The cam edge 18, for its part may have, for example, in the angular direction V: a ramp 25 which extends radially inwards in the angular direction V, with a relatively steep slope, then a rounded portion 26 which also extends radially inwards in the angular direction V, with a smaller slope than the ramp 25.

  The portion 26 of the cam edge may for example be connected to the first edge 20 by a flat 27, or other.

  Each of the seed pusher 19 cooperates with a blocking grain 28, made for example of metal, which may for example comprise an enlarged head 29 provided with an external toothing 30 in a circular arc adapted to engage with a circular internal toothing. 31 of the first frame 7. The toothing 30 of the blocking grain 28 may for example have a radius of curvature (for example the radius of the pitch circle of the toothing) less than the radius of curvature (for example the radius of the pitch circle). of the toothing 31. By way of non-limiting example, the radius of curvature of the toothing 30 may be approximately 1 to 5% less than the radius of curvature of the toothing 31.

  The blocking grain 28 further comprises a body 32 narrower than the head 29, which extends substantially radially inwardly from the head 29. The body 32 is delimited by first and second lateral edges 33, 34 which are arranged respectively facing first and second guides 36, 37. The first lateral edge 33 of the blocking grain may be extended by a rounded convex rear potion facing the concave portion 23 of the second edge of the grain elevator.

  The blocking grain slides radially between: - the locked position shown in FIG. 5, where the toothing 30 of the blocking grain engages the toothing 31 of the first frame, - and an unlocked position where the blocking bit 28 is moved radially inwardly so that its toothing 30 does not interfere with the toothing 31.

  The first and second guides 36, 37 may consist for example of two edges respectively belonging to two bosses 38a, 38b belonging to the second armature 8.

  The first guide 36 may for example have a generally convex shape, as in the example shown in the drawings, and it defines with the first lateral edge 33 of the blocking grain a free space 39 in the form of a wedge in which is engaged the shoot -grain 19. More specifically, the first edge 20 of the grain elevator (or at least the convex portion of this first edge, if this first edge is not convex over its entire length) comes into contact with the first guide 36 when the grain elevator is pushed radially outwards in the active position by the cam 11.

  In said active position of the grain elevator, the convex front portion 22 of the second edge of the grain elevator is in contact with the first side edge 33 of the blocking grain, which pushes the blocking grain into the locked position.

  The second lateral edge 34 of the blocking grain, for its part, may for example have a rectilinear shape and the second guide 37, against which slides said second side edge 34, may also have a rectilinear shape.

  Moreover, each seed-shoot 19 further cooperates with a locking grain 40 made for example of metal, which may comprise for example an enlarged head 41 provided with an external toothing 42 adapted to engage the internal toothing 31 of the first frame. The toothing 42 may for example have the same radius of curvature (that is to say the same radius of pitch circle) as the toothing 31.

  The enlarged head 41 of the locking grain 40 is extended radially inwards, by a narrower body 43 having two lateral edges 44, for example of rectilinear shape, which slide between two guides 45 integral with the second frame 8. The guides 45 can be formed for example by straight edges belonging to the bosses 38a, 38b these edges being parallel to the lateral edges 44 of the locking grain.

  The locking grain 40 can thus slide radially between: - the locked position visible in FIG. 5, where the toothing 42 of the locking grain engages the toothing 31, - and an unlocked position where the locking grain 40 is moved radially inwardly so that its toothing 42 does not interfere with the toothing 31.

  A slight clearance may advantageously be provided between the lateral edges 44 of the locking pin and the guides 45, this clearance being able to be sized to allow relative pivoting movement between the first and second frames 7, 8 when the locking pin 40 is in position. locked position. For example, the game in question can be sized to allow relative angular movement corresponding to the angular extent of a half tooth width of the toothing 31, seen from the axis of rotation Y. When the cam edge 13 of the cam 11 acts on the cam edge 18 of the grain elevator 19, the first edge 20 of this grain elevator supports, by its rear portion adjacent to the flat portion 27, on a rear portion 46 of the body 43 of the corresponding locking grain, thus maintaining this locking grain in its locked position.

  As shown in FIGS. 3 and 4, the elements of the locking device 10 which have just been described are repeated at 120 from each other, so that the locking device 10 comprises, in total: - three blocking grains 28 arranged at 120 from each other, three locking grains 40 arranged at 120 from each other, - and three grain pumps 19 arranged at 120 from each other.

  Furthermore, the locking device 10 further comprises a disk-shaped control plate 47 (FIG. 3) made, for example, of cut sheet metal, which is secured to the cam 11 and which partially overlaps the cam 11, the seed pumps. 19, the grains 28, 40 and the bosses 38a, 38b.

  The control plate 47 may for example comprise cutouts 48 which are nested without play on pins 49 belonging to the cam 11, to secure the control plate with the cam.

  In addition, the control plate has cut-out slots 50 which are distributed around the periphery of the control plate with an angular pitch of 60. The slots may be identical and each have a circular portion 51 centered on the Y axis, this circular portion being extended in the locking direction V by a ramp 52 extending radially inwardly in the angular direction. V. The slots 50 receive protruding pins 53, 54 respectively belonging to the bodies of the blocking grains 28 and locking grains 40. These pins 53, 54 are arranged in the circular portions 51 of the slots 50 when the articulation mechanism is in the locked position, as shown in FIG.

  When the handle 6 is actuated as far as the stop in the unlocking direction D, as represented in FIGS. 6 and 7: the cam edges 13 of the cam 11 no longer act on the cam edges 18 of the push rods, which allows said seed pushers to move radially inwards in the erased position visible in FIG. 7, where the rounded portions 26 of the cam edges of the seed pushers are opposite circular portions 12 of the cam, the flat part 27 of each push grain can for example be arranged laterally with respect to one of the projecting cam edges 13 of the cam 11 (Figure 7), and the ramps 52 of the slots 50 act on the pins 53, 54 grains 28, 40 to move them radially inwards in the unlocked position (Figure 6).

  In this unlocked position, the first and second armatures 7, 8 can pivot freely relative to each other about the Y axis, so that a user can adjust the inclination of the backrest 2, for example by acting on this backrest manually or with his back (usually against an elastic bias tending to move the backrest 2 forward).

  When the user releases the handle 6, it moves with the cam 11 in the locking angular direction V, so that, as can be seen in Figures 8 and 9, the cam edges 13 of the cam 11 act first on the ramps of the cam edges of the seed pushers 19 to move said seed pushers outward in the wedge-shaped spaces 39, while pivoting them so that the rear portion of their first edge 20 bears against the rear portion 46 of the body of the locking grains 40.

  In this intermediate position, the toothing 42 of the locking grains 40 is already at least partially engaged in the toothing 31 of the first reinforcement 7 and the toothing 30 of the blocking grains 28 can also be partially engaged in the toothing 31.

  In the rest of the return movement of the cam 11 to its rest position corresponding to FIGS. 3 to 5, the cam edges 13 of the cam act on the rounded portions 26 of the cam edges 18 of the push rods to continue moving. the grain elevator 19 to their active position (Figures 3 to 5). During this movement, the seed pushers 19 move radially outward in the wedge-shaped free spaces 39 and / or pivot so that the rear portion of their first edge 20 moves radially outwardly against the rear portion 46 of the corresponding locking grain 40.

  These movements are facilitated by: the convex shapes of the first and second edges 20, 22 of the grain elevator, the rectilinear or convex shapes of the first guide 36 and the first lateral edge 33 of the blocking grain, the radius of curvature the toothing 30 of the blocking grain, smaller than the radius of curvature of the toothing 31, - and the clearance between the lateral edges 44 of the locking ring and the guides 45.

  At the end of this movement, the grains 28, 40 are all engaged completely in the toothing 31, and the grain driver 19, thanks to its wedge shape eliminates any angular play between the first and second frames 7, 8. It will be noted when the blocking grain 28 arrives in the locked position, a single tooth of its toothing 30 is engaged at the bottom of the toothing in the toothing 31, so that the locking grain 28 is substantially in isostatic equilibrium between: - the point of quasi-point contact constituted by its tooth engaged at the bottom of the toothing, its point of almost point contact with the convex front portion of the second edge of the seed-shoot, and its zone of contact with the second guide 37.

  This gives a lock without play and high strength despite the geometric dispersions of the parts of the mechanism due to manufacturing tolerances.

Claims (13)

  Hinge mechanism for a vehicle seat comprising: first and second rigid armatures (7, 8) pivotally mounted relative to one another about an axis of rotation (Y); 31) secured to the first armature (7) and forming at least one circular arc centered on the axis of rotation (Y), - at least one blocking groove (28) which has a toothing (30) and which is mounted sliding between first and second guides (36, 37) belonging to the second armature (8) between on the one hand, a locked position where the toothing (30) of the blocking grain engages the toothing (31) of the first armature for immobilizing the first and second armatures relative to each other, and secondly, an unlocked position where said blocking grain (28) does not interfere with the toothing (31) of the first armature said blocking grain (28) having first and second side edges (33, 34) and at least the first lateral d-section (33) delimiting, with the first guide (36), a wedge-shaped free space (39); - a wedge-shaped seed push (19) penetrating said free space (39) and mounted movably on the second armature (8) between on the one hand, an active position where said grain elevator (19) pushes the blocking grain (28) in the locked position, and secondly, an erased position where said grain elevator allows at the blocking grain to move into the unlocked position, and a control cam (11) adapted to selectively either urge the seed elevator (19) into the active position, or allow the seed elevator to move into the erased position , characterized in that it further comprises at least one locking groove (40) which has a toothing (42) and which is movably mounted on the second armature (8) between on the one hand, a locked position where the toothing {42) locking grain is engaged with the toothing (31) of the first frame, and on the other hand, an unlocked position where said locking grain does not interfere with the toothing of the first frame, and that the seed elevator (19) is adapted to push the locking grain (40) into position locked when said seed elevator is in the active position, and said seed elevator (19) is adapted to allow the locking grain (40) to move into the unlocked position when said seed elevator is in the erased position.   2. articulation mechanism according to claim 1, wherein the toothing (30) of the blocking grain has a lower radius of curvature to the toothing (31) of the first frame.   3. articulation mechanism according to claim 1 or claim 2, wherein the toothing (42) of the locking grain has a radius of curvature substantially equal to the radius of curvature of the toothing (31) of the first frame.   4. articulation mechanism according to any one of the preceding claims, wherein the grain elevator (19) has first and second edges (20, 21) which converge in wedge shape and which each have at least one convex portion (20, 22), the convex portion (20) of the first edge of the grain elevator contacting the first guide (36) and the convex portion (22) of the second edge of the grain elevator contacting the first edge lateral (33) of the blocking grain when said seed elevator is in the active position.   5. articulation mechanism according to claim 4, wherein the first guide (36) has a bearing portion is convex or rectilinear, against which comes into contact with the convex portion (20) of the first edge of the grain elevator when said seed elevator is in the active position.   6. articulation mechanism according to claim 4 or claim 5, wherein the first lateral edge (33) of the blocking grain has a bearing portion is convex or rectilinear, against which comes into contact with the convex portion (22). ) of the second edge of the grain elevator when said grain elevator is in the active position.   7. articulation mechanism according to any one of the preceding claims 4 to 6, wherein the convex portion (22) of the second edge of the grain elevator is extended towards the axis of rotation (Y) by a concave portion (23). ) having a concavity turned towards the blocking grain (28).   8. articulation mechanism according to claim 7, wherein the locking grain (28) has a rear edge (35) convex facing the concave portion (23) of the second edge of the grain elevator.   9. hinge mechanism according to any one of claims 4 to 8, wherein the second lateral edge (34) of the blocking grain is rectilinear and comes into contact with a rectilinear portion (37) belonging to the second guide when said grain lock is in the locked position.   10. articulation mechanism according to any one of claims 4 to 9, wherein the first edge (20) of the grain elevator comprises a rear portion arranged to abut against the locking grain (40), to the opposite of the toothing (42) of said locking grain.   The hinge mechanism according to any of the preceding claims, wherein the grain elevator (19) has a cam edge (18) opposite the first and second edges (20, 21) of said grain elevator. and the control cam (11) is arranged to engage said cam edge (18) to urge the seed elevator radially outwardly into the active position.   12. articulation mechanism according to any one of the preceding claims comprising a plurality of grain pusher (19) each cooperating with a blocking grain (28) and a locking grain (40).   13. Vehicle seat comprising a seat (3) and a backrest (2) interconnected by at least one articulation mechanism (5) according to any one of preceding claims.