FIELD OF INVENTION
[001] The present disclosure relates to a field of automotive seat recliners. More 5 specifically, the present disclosure relates to a recliner assembly providing impact/dynamic stability at lock condition, dynamic locking, zero free play at lock condition and consistency in unlocking recliner assembly.
BACKGROUND 10
[002] It is known vehicles such as cars, buses, trucks and so on include seat assemblies for supporting occupants within the vehicles. Generally, the seat assemblies include a seat cushion and a seat back. The seat back has a front surface for supporting the occupant and an opposite rear surface. It is known that the seat back is pivotally interconnected to the seat 15 cushion by a recliner mechanism.
[003] The recliner mechanism comprises an outboard recliner and an inboard recliner. The outboard recliner is provided with a lever to actuate recliner mechanism. Upon activation, the recliner mechanism allows pivotal adjustment of the seat back relative to the seat cushion 20 between a plurality of reclined position about a fixed, and single pivot axis. Generally, the reclining mechanism includes a lower and upper arm mounted on the seat cushion and seat back respectively, to house a locking cum unlocking means, which is effected by a rotatable cam operated by a splined shaft which passes through the lower and upper arms of the recliner. Further, the reclining mechanism comprises a spiral springs mounted on the shaft to 25 apply radial forces on the cam for rotation during locking and unlocking operations.
[004] The reclining mechanism further comprises a plurality of sectors coupled to the cam. The plurality of sectors is configured to slidably move in radial direction between a locked and an unlocked position. It is known that each of plurality of sectors comprises a plurality of 30 teeth at outer portion. The teeth provided in the sectors are configured to engage with inner teeth of an upper part of the recliner in order to lock the seat position.
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[005] It should be noted that existing recliner mechanisms have several problems. For instance, when the recliner mechanism is actuated, at first, the outboard recliner is rotates which in turn rotates the shaft followed by the inboard recliner. It should be understood that the inboard recliner is actuated with a hiatus upon actuating the outboard recliner. As a result, the inboard recliner does not rotate in synchronization with the outboard recliner. 5
[006] In addition, whenever there is a load applied suddenly on the recliner mechanism, the plurality of sectors are made to slide which will result in unlocking of the plurality of sectors with the teeth at outer portion. As a result, the recliner mechanism is unlocked and the seat is pushed towards or away from the seat cushion. 10
[007] In addition, automotive seats have free travel requirements (seat back should recline without need of lever operation). Recliner has to lock immediate after the free travel limit (First lock) without skipping to the other lock conditions. The velocity and mass of the back rest play an important role for locking the recliner at first lock (dynamic locking). As a result 15 of mass and velocity, seat back recliner mechanism will skip from first lock.
[008] As presented above, the teeth on the plurality of sectors are made to come in contact with the inner teeth of the upper part of the recliner in order to lock the seat position. Generally, the teeth on the plurality of sectors are provided in a uniform structure. The 20 uniform structure of the teeth may result in partial locking of the teeth of the plurality of sectors with the inner teeth of the upper part.
[009] Therefore, there is a need for a recliner assembly that overcomes the problems discussed above and provides stability during operation of the recliner assembly. 25
SUMMARY
[010] This summary is provided to introduce concepts related to a recliner assembly and the concepts are further described below in the detailed description. This summary is not 30 intended to identify essential features of the claimed subject matter nor is it intended for use in determining or limiting the scope of the claimed subject matter.
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[011] In one aspect of the present disclosure, a recliner assembly for operating a seating unit is disclosed. The recliner assembly comprises at least one recliner coupled to the seating unit with the help of a connecting rod. The recliner comprises, a lower part, an upper part, a cover ring to hold the lower part and the upper part, a guide plate coupled to a cam, the cam 5 coupled to an actuator, and a plurality of sectors coupled to the cam. The plurality of sectors is configured to slide radially between a locking position and an unlocking position. The profile of the cam and the sectors facilitate in nullifying the force exerted on the sectors in the lock position. Further, each of the sectors comprises teeth with variable profile to lock the sectors with the upper part. 10
[012] In another aspect of the present disclosure to provide a cam mould at the cam to reduce or avoid noise generated when the cam comes in contact with other metal parts.
[013] In another aspect of the present disclosure to provide a cavity in the lower part and 15 cam to synchronize the movement of the cam with operation of a lever or the actuator.
[014] In another aspect of the present disclosure to provide a safe locking surfaces in sector and cam to safeguard the recliner from unlocking for small movement of lever due to inertia.
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[015] In another aspect of the present disclosure to provide a sector and cam dynamic locking surfaces to lock the recliner when upper part is moving with inertial load.
[016] In another aspect of the present disclosure to provide a wedge at one of the sectors to compensate tolerance of the lower part, sector, the upper part and prevents angular rotation of 25 the sector when recliner is in lock condition.
[017] In another aspect of the present disclosure to provide variable teeth on sectors which prevents the recliner from being half locked and improve the locking performance of recliner.
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5
BRIEF DESCRIPTION OF DRAWINGS
[018] The detailed description is described with reference to the accompanying figures. In the figures, a reference number is used to identify a part of recliner mechanism. The same 5 numbers are used throughout the drawings to refer like/similar features and components.
[019] FIG. 1 illustrates a perspective view of a recliner assembly with seat structure, in accordance with an embodiment of the present disclosure;
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[020] FIG. 2A, 2B and 2C illustrate an exploded view and a perspective view of the first recliner and the second recliner coupled via the connecting rod, respectively, in accordance with an embodiment of the present disclosure;
[021] FIG. 3A illustrates an exploded view of the first recliner, in accordance with an 15 embodiment of the present disclosure;
[022] FIG. 3B and 3C illustrate assembly of the sleeve in the lower part, in accordance with an embodiment of the present disclosure;
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[023] FIG. 3D and 3E illustrate assembly of the actuator in the lower part, in accordance with an embodiment of the present disclosure;
[024] FIG. 3F illustrates a cross-sectional view of the cam mould coupled to a cam, in accordance with an embodiment of the present disclosure; 25
[025] FIG. 3G illustrate a perspective view of the cam comprising the cam mould, in accordance with an embodiment of the present disclosure;
[026] FIG. 3H illustrate configuration of the cam and actuator assembly for non 30 synchronization recliner, in accordance with one exemplary embodiment of present disclosure;
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[027] FIG. 3I and 3J illustrate an exploded view and perspective view of the cam and the plurality of sectors aligned with respect to the actuator and the lower part, in accordance with an embodiment of the present disclosure;
[028] FIG. 3K illustrates a cross-sectional view of the recliner assembly comprising the 5 actuator, in accordance with an embodiment of the present disclosure;
[029] FIG. 3L illustrates a perspective view of the lower part comprising the actuator, in accordance with an embodiment of the present disclosure;
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[030] FIG. 3M illustrates an exploded view of recliner sub assembly for plastic actuator and retainer, in accordance with one exemplary embodiment of the present disclosure;
[031] FIG. 3N illustrates an exploded view of recliner sub assembly with plastic actuator and retainer, in accordance with one exemplary embodiment of the present disclosure; 15
[032] FIG. 3O and 3P illustrates an recliner assembly and cross sectional view of assembled recliner with plastic actuator and retainer, in accordance with one exemplary embodiment of present disclosure;
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[033] FIG. 3Q illustrates an exploded view of recliner assembly with actuator, in accordance with yet another exemplary embodiment of the present disclosure;
[034] FIG. 4A and 4B illustrate configuration of the cam with respect to the actuator and lower part, in accordance with one embodiment of present disclosure; 25
[035] FIG. 4C and 4D illustrate configuration of the cam with respect to the plastic actuator and lower part, in accordance with one exemplary embodiment of present disclosure;
[036] FIG. 4E and 4F illustrate configuration of the cam with respect to the plastic actuator 30 and lower part, in accordance with one exemplary embodiment of present disclosure;
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[037] FIG. 4G to 4L illustrate operation of the cam with respect to the actuator and lower part, in accordance with an embodiment of the present disclosure;
[038] FIG. 5 illustrates the cam, in accordance with an embodiment of the present disclosure; 5
[039] FIG. 6 illustrates the sector, in accordance with an embodiment of the present disclosure;
[040] FIG. 7A to 7D illustrate operation of the cam and the sectors from lock position to 10 unlock position, in accordance with an embodiment of the present disclosure;
[041] FIG. 7E and 7F illustrate operation of the cam and the sectors from unlock position to lock position, in accordance with an embodiment of the present disclosure;
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[042] FIG. 8A and 8B illustrate the sector comprising a wedge, in accordance with an embodiment of the present disclosure;
[043] FIG. 9 illustrates the lower part comprising the sector having the wedge in lock condition, in accordance with an embodiment of the present disclosure; 20
[044] FIG. 10A and 10B illustrate the wedge comprising a pic and the pin being driven by a guide plate, in accordance with an embodiment of the present disclosure; and
[045] FIG. 11A and 11B illustrate the sector comprising variable teeth, in accordance with 25 an embodiment of the present disclosure.
DETAILTED DESCRIPTION
[046] The following detailed description is intended to provide example implementations to 30 one of ordinary skill in the art, and is not intended to limit the disclosure to the explicit disclosure, as one of ordinary skill in the art will understand that variations can be substituted that are within the scope of the disclosure as described.
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[047] The present disclosure relates to a recliner assembly for operating a seating unit. The seat unit comprises at least one recliner coupled to the seating unit with the help of adaptors. The recliner comprises, a lower part, an upper part, a cover ring to hold the lower part and the upper part, a guide plate coupled to the cam, a cam coupled to the actuator, and a plurality of 5 sectors coupled to the cam and guide plate, a wedge coupled to cam and guide plate or sector, Internal spring unit coupled to cam and lower part, handle spring coupled to actuator and lower adaptor. The plurality of sectors is configured to slide radially between a locking position and an unlocking position. The profile of the cam and the sectors facilitate in nullifying the force exerted on the sectors in the lock position. The profile of the cam and 10 sector facilitate in dynamic locking when upper part is in motion. Further, each of the sectors comprises teeth with variable profile to avoid half or partial locking of sectors with the upper part.
[048] The various implementations of the recliner assembly are explained with the help of 15 Figures 1-11B.
[049] Referring to FIG. 1, a perspective view of a seat unit 100 with recliner assembly is shown, in accordance with one embodiment of the present disclosure. The seat unit 100 comprises a cushion frame 105 and a support frame 110 connected pivotally to cushion frame 20 105. The seat unit 100 comprises a first recliner 115 and a second recliner 120. The first recliner 115 and the second recliner 120 are coupled using a connecting rod 125. The first recliner 115 comprises a lever 130 used to operate the first recliner 115 which in turn operates the second recliner 120 through the connecting rod 125. The first recliner 115 and second recliner 120 can be coupled to cushion frame 105 and support frame 110 using 25 welding or by intermediate elements.
[050] Referring to FIG. 2A, an exploded view of a twin recliner unit 101 with the first recliner 115 and the second recliner 120 and connecting rod 125 is shown, in accordance with one embodiment of the present disclosure. As can be seen, the first recliner 115 is coupled to 30 the cushion frame 105 using a first adapter 117. Similarly, the second recliner 120 is coupled to the cushion frame 105 using a second adapter 122. The first recliner 115 may further comprise a handle spring 118 used to couple to the lever 130 and first adaptor 117.
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[051] Referring to FIG. 2B, a perspective view of the twin recliner unit 101 with the first recliner 115 and the second recliner 120 coupled via the connecting rod 125 is shown, in accordance with one embodiment of the present disclosure. As the connecting rod 125 is coupled to first recliner 115 and second recliner 120 by riveting, welding or with any other possible means. 5
[052] Referring to FIG. 2C, a perspective view of twin recliner unit 101 with exemplary embodiment or version of the present disclosure. The first recliner 115 and the second recliner 120 coupled via the connecting rod 125 is shown. As the connecting rod 125 with non circular section is passes through first recliner 115 and second recliner 120. Handle 10 spring 118 and Handle knob 119 are inserted to connecting rod and are fastened by any means. As can be seen, the connecting rod 125 is not permanently fastened to either first recliner 115 or second recliner 120.
[053] Now referring to FIG. 3A, an exploded view of the first recliner 115 is shown, in 15 accordance with one embodiment of the present disclosure. It is to be noted that second recliner 120 is symmetric to first recliner 115. As can be seen, the first recliner 115 comprises a lower part 205 and an upper part 210. The lower part 205 and an upper part 210 may be coupled using a cover ring 215. The lower part 205 comprises an actuator 220 coupled to the lever 130 and cam 225. The first recliner 115 further comprises a cam 225 operably coupled 20 to the actuator 220 and is configured for bi-directional rotation in an approximate semi-circular path. The cam 225 further comprises a cam mould 226 protruding from the cam 225.
[054] The first recliner 115 further comprises a plurality of sectors 230 operably coupled to cam 225. The lower part 205 further comprises a plurality of internal spring 235 configured 25 for coupling the cam 225 and there by plurality of sectors 230. The plurality of sectors 230 are configured to slide radially when guide plate 240 coupled to the cam 225 is actuated by the actuator 220. In one example, the plurality of sectors 230 and the plurality of internal spring 235 are disposed at approximately 120 degrees to each other about a vertical axis so as to enable a self-centering mechanism. Further, the first recliner 115 comprises a guide plate 30 240 to guide the plurality of sectors 230.
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[055] As can be seen from FIG. 3A, the lower part 205 may further comprises a sleeve 245 coupled to the actuator 220. In one example, the sleeve 245 is made up of noise resistance material.
[056] Referring to FIG. 3B, an exploded view of the lower part 205 and sleeve 245 is shown. The lower part 205 is provided with a synchronization cavity 206 to receive the 5 sleeve 245. The synchronization cavity 206 is defined based on section and travel of actuator 220.
[057] Referring to FIG. 3C, assembly of the sleeve 245 in the lower part 205 is explained. The sleeve 245 received in the cavity 206 is shown, in accordance with one embodiment of the present disclosure. The sleeve 245 acts as the noise insulator between lower part 205 and 10 actuator 220.
[058] Now referring to FIG. 3D and 3E, is explained. Referring to FIG. 3D, the actuator 220 is aligned in axis with the lower part 205 comprising the sleeve 245. The actuator 220 is provided with a collar 221 which is received in the lower part synchronization cavity 206. 15 Now referring to FIG. 3E, the actuator 220 received in the lower part 205 comprising the sleeve 245 is shown, in accordance with one embodiment of the present disclosure. The collar 221 along with lower part synchronization cavity 206 reduces the play of actuator 220.
[059] Referring to FIG. 3F and 3G, is explained. Referring to FIG. 3F, a cross-sectional 20 view of the cam mould 226 coupled to the cam 225 is shown, in accordance with one embodiment of the present disclosure. Further, referring to FIG. 3G shows a front view of the cam 225 comprising the cam mould 226 and a cam cavity 227. The cam cavity 227 is defined based on section and travel of actuator 220 interface.
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[060] Referring to FIG. 3H, one exemplary embodiment of cam 225 and actuator 220 is explained. For non synchronization recliners or for single side recliner units the cam 225 and actuator 220 are generally fixed together. The cam 225 is coupled with actuator 220 by means of welding, riveting or press fit in accordance with another exemplary embodiment of the present disclosure. 30
[061] Further, FIG. 3I, an exploded view of the cam 225 and the plurality of sectors 230 aligned with respect to the actuator 220 and the lower part 205 is shown. Further, FIG. 3J,
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perspective view shows the assembled condition of cam 225 and the plurality of sectors 230 coupled to the actuator 220 and the lower part 205.
[062] Referring to FIG. 3K, a cross-sectional view of the lower part 205 comprising the actuator 220 is shown. As can be seen, the lower part 205 comprises the sleeve 245. Further, 5 the actuator 220 is coupled to the cam 225 having the cam mould 226.
[063] Referring to FIG. 3L, a perspective view of the first recliner 115 assembly is shown, in accordance with one embodiment of the present disclosure. As can be seen, the actuator is part of the first recliner 115 heart assembly. One end of the actuator 220 is coupled to 10 connecting rod 125, other end is connected to lever 130 and handle spring 118.
[064] Referring to FIG 3M to 3P, one exemplary embodiment of first recliner 115 is explained. Referring to FIG 3M, an exploded view of first recliner 115 sub assembly for one exemplary embodiment of present disclosure is explained. Cam cavity 227 of cam 225 profile 15 and synchronization cavity 206 of lower part 205 are with different geometrical definition. As can be seen, only cam 225 is part of sub assembly of first recliner 115 with out actuator 220 and sleeve 245. The definition of the upper part 210, Guide plate 240, plurality sector 230, plurality internal spring 235, lower part 205 and covering 215 are intact.
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[065] Referring to FIG 3N, an exploded view of exemplary embodiment of first recliner 115 is explained. In one exemplary embodiment the actuator 220 is made of plastic which can be inserted in to the first recliner 115 sub assembly from the lower part 205 side in to the synchronization cavity 206 and the cam cavity 227 and locked in position with the retainer 260. 25
[066] Referring to FIG 3O and 3P, normal view and an cross-sectional view of first recliner 115 with the plastic actuator 220 and the retainer 260 is shown. The plastic actuator 220 and the retainer 260 are snap fitted. As can be seen, the plastic actuator 220 internal cavity generally as per the form of connecting rod 225. As stated above non circular 30 connecting rod 225 can pass through the actuator in accordance with one exemplary embodiment of the present disclosure.
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[067] Referring to FIG. 3Q, yet another exemplary embodiment of first recliner 115 is explained. Methodology will remain as explained above with one exemplary cam 225 and actuator 220. Referring to FIG. 3Q, Exploded view of first recliner 115 for one exemplary embodiment of present disclosure is explained. Cam cavity 227 of cam 225 profile and synchronization cavity 206 of lower part 205 are with different geometrical definition as per 5 the actuator 220. The definition of The upper part 210, Guide plate 240, plurality sector 230, plurality internal spring 235, lower part 205 and covering 215 are intact.
[068] Referring to FIG. 4A to 4M, Different versions of cam 225, lower part 205 actuator 220 are described along with operation of the cam 225 with respect to the actuator 220 is 10 explained. As known, when the first recliner 115 is rotated there is a possibility of delay in the second recliner 120 due to tolerances of internal parts. Because of the delay any one recliner either first recliner 115 or second recliner 120 will be in lock condition and other will be in unlock, which makes support frame twisted. In order to compensate the delay, the synchronization cavity 206 is provided in the lower part 205 and cam the cavity 227 is 15 provided in the cam 225. Specifically, the synchronization cavity 206 is provided such that the actuator 220 rotates/engages in the synchronization cavity 206 before engaging with the cam 225.
[069] Referring to FIG. 4A, the actuator 220 in contact C with the lower part 205 or sleeve 20 245 is shown. The actuator 220 is acted up on by handle spring 118 force in such a way that it should be contact C with lower part 205 or sleeve 245. The gap GG is provided between the actuator 220 and the lower part 205 which allows the actuator 220 rotates only in unlocking direction.
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[070] Referring to FIG. 4B, the gap G will vary as cam locking angle varies due to tolerances of individual internal part features. The gap G is defined considering worst case cam locking angle between the first recliner 115 and second recliner 120. As can be seen, the actuator 220 orientation will not affect for tolerances of internal parts due to its position is defined by lower part 205. The actuator 220 has to rotate for a small angle to contact the cam 30 225, these rotation angle is governed by the gap G of individual recliners. As a result, the first recliner 115 and the second recliner 120 are operated in synchronization.
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[071] Referring to FIG. 4C and 4D, describes the one exemplary embodiment of cam cavity 227 of cam 225, the synchronization cavity 206 of the lower part 205 and plastic actuator 220 in accordance with one exemplary embodiment the present disclosure. The functionality requirement of the plastic actuator 220, lower part 205 and cam 225 remain same as explained above. The geometrical definition of synchronization cavity 206 and cam 5 cavity 227 are defined as per the plastic actuator 220.
[072] Referring to FIG. 4E and 4F, describes yet another exemplary embodiment of cam cavity 227 of cam 225, the synchronization cavity 206 of the lower part 205 and actuator 220 in accordance with one exemplary embodiment the present disclosure. The functionality 10 requirement of the actuator 220, lower part 205 and cam 225 remain same as explained above. The geometrical definition of synchronization cavity 206 and cam cavity 227 are defined as per the actuator 220.
[073] Referring to FIG. 4G to 4J, example illustrations showing rotation of the actuator 15 220, and rotation of the cam 225 when the actuator comes in contact with the cam 225 are shown, in accordance with one embodiment of the present disclosure. Referring to FIG. 4G, actuator 220 position with lower part 205 is shown for free unlock travel of first recliner 115. Referring to FIG. 4H, the actuator 220 is in contact with the cam 225. As can be seen the cam 225 angular rotation R2 is less than actuator 220 angular rotation R1. Referring to FIG. 20 4I, actuator 220 position with lower part 205 is shown for full travel of first recliner 115. Referring to FIG.4J, the cam 225 angular rotation R4 is less than actuator 220 angular rotation R3. As noted above connecting rod 125 is coupled to the actuator 220 of first recliner 115 and second recliner 120, the actuator 220 angular rotation is same for both first recliner 115 and second recliner 120. There by both the recliner unlock angles will be same. 25
[074] As specified above, the cam 225 is provided with the cam mould 226. In one example, the cam mould 226 may be made up of plastic. The cam mould 226 is provided to avoid noise generated when the metal parts come in contact with one another.
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[075] It is known that inertial load or pressure may be applied on the lever 130 accidently. Based on existing designs, the actuator 220 may get activated and operated the cam 225 which in turn unlocks the sectors 230 from the upper part teeth 213. In order to safeguard the
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recliner for inertial and vibration movements of the lever, the present disclosure discloses the cam 225 and safe locking feature design which facilitates in the cam 225.
[076] It is also known that support frame 110 is acted up on by dynamic forces from the occupant due to static and inertia during service. The first recliner 115 and or the second 5 recliner 120 have to resists these loads to safe the occupant. These loads are transfer to cam from the plurality sectors 230 and the upper part 210. To stable the recliner for dynamic and static loads or forces, the present disclosure discloses the cam 225 and the plurality sector 230 design which facilitates in the cam 225 and the plurality sector 230 nullifies the forces and make the cam 225 stable. Referring to FIG. 5 and FIG. 6, the cam 225 and the sector 230 10 designs are explained, respectively.
[077] Referring to FIG. 5, the cam 225 is shown. The cam 225 comprises a cam master leg 271, a cam master lock surface 272, a cam safe lock surface 273, cam follower leg 274, and a cam follower lock surface 275. 15
[078] Now referring to FIG. 6, the sector 230 is shown. The plurality sector 230 comprises a sector master leg 280, a sector master lock surface 281, a sector safe lock surface 282, a dynamic lock surface 283, a sector follower leg 285, and a sector follower lock surface 286.
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[079] Now referring to FIG. 7A, the cam 225 coupled to the plurality of sectors 230 is shown. Specifically, the FIG. 7A is shown to illustrate the plurality sectors 230 in locked position. As can be seen, the cam master lock surface 272 is in contact with the sector master lock surface 281. There will be a small gap between the cam follower lock surface 275 and the sector follower lock surface 286. 25
[080] Referring to FIG. 7B, position of the cam 225 when a load (force F) is applied from the plurality sector 230 is shown. The lock profiles of cam 225 and plurality sector 230 are defined in such a why that follower lock surfaces of cam 225 and plurality sector 230 will come in to contact after master lock surfaces of cam 225 and plurality sector 230 start taking 30 the load F. When the load F started transmitting through follower lock surfaces, the cam follower lock surface 275 is translated to hit the sector master leg 281 which is in opposite direction. As a result, there will not be any movement in the cam 225. Further, if the force F is applied only on the cam master lock surface 272, then the force pushes the cam 225 to
15
rotate in locking direction which is stable. The cam 225 and the plurality sector 230 lock profile are designed in such a way that cam master leg 271 and sector master leg 280 will have first contact followed by cam follower leg 274 and sector follower leg 285 during static and dynamic loading of first recliner 115 and/or second recliner 120.
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[081] Now referring to FIG. 7C, the first recliner 115 intermediate unlock position is shown. As can be seen, the cam safe lock surface 273 is in contact with the sector safe lock surface 282 for small angular rotation of cam 225. As stated above the first recliner 115 is stable for small angular rotation of actuator 220 and cam 225.
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[082] Further, FIG. 7D, the first recliner 115 complete unlock position is shown. As can be seen, the cam safe lock surface 273 is in contact with the plurality Sectors 230 in unlocking position is shown. Further rotation of cam 225 towards unlocking is not possible.
[083] As can be noted from FIG. 7A to 7D, the sector master legs 280 of the plurality 15 sectors 230 always in contact with the cam 225. Further, the sector follower leg 285 will be in contact for a shorter duration with the cam 225. It should be understood that if only the sector master legs 280 are in contact, then it will store elastic strain energy during loading and move the cam 225 towards unlock position after removal of the load.
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[084] In order to balance the energy, both the sector master legs 280 and the sector follower legs 285 should be in contact. The sector follower leg 285 contact lags the sector master leg 280 contact to keep the momentum towards locking Therefore, the cam 225 and plurality sector 230 contact surfaces defined in such a way that both follower and master legs leads to contact during loading as shown in FIG. 7B. As the forces are directed to master legs 280, 25 the force applied on any of the plurality sectors 230 will be nullified and the stability is provided when the load is applied during the locking position.
[085] It is expected to lock the first recliner 115 when the upper part 210 in motion. This requirement is typically referred as dynamic locking. As stated above recliner has to lock at 30 first lock during free travel. Yet with another requirement it is known that Recliner has to lock immediate after the free travel limit (First lock) without skipping to the other lock conditions. The velocity and mass of the support frame 110 play impotent role for locking the recliner at first lock (dynamic locking). The cam 225 and the plurality sector 230 lock profile
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plays an impotent role in dynamic locking of recliner. Referring to FIG. 7E and 7F, the role of cam 225 and the plurality sector 230 during dynamic locking is explained.
[086] Referring to FIG. 7E and 7F, Normal and detail view of the cam 225 and the plurality sector 230 during free travel to first lock configuration is shown. The dynamic lock 5 surface 283 of the plurality sector 230 is in continuous contact with cam 225. Refereeing to FIG. 7E, teeth of the plurality sector 230 are about to lock with teeth of the upper part 210. Small rotation towards locking makes cam safe locking surface 273 is in contact with sector safe lock surface 282. As explained above the plurality sector 230 will be stable during locking from free travel to first lock. There by dynamic locking is achieved. 10
[087] In one embodiment, one of the plurality sectors 230 may be provided with a wedge 232 and a split sector 233. In one example, the wedge 232 and a split sector 233 may be formed by cutting out the plurality sector 230. In another example, the wedge 232 may be provided as a separate part that can be removably coupled to the split sector 233. 15
[088] Referring to FIG. 8A, an exploded view of the split sector 233 comprising the wedge 232 is shown. Further, FIG. 8B shows the wedge 232 coupled to the sector 233 is shown.
[089] Furthermore, FIG. 9, loaded condition of the sprit sector 233 and the wedge 232 is 20 explained. The lower part 205 comprising two the plurality sector 230, the sprit sector 233, wedge 232, cam 225, plurality internal spring 235 and actuator 220 is shown. During the operation, the wedge 232 is driven by the sector 230. In other words, the sector 230 holds the wedge 232 in position during locking and unlocking of the sectors 230.
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[090] It should be understood that the wedge 232 is provided for compensating tolerances of the lower part 205, split sector 233 and upper part 210. Further, the profile of the wedge 232 is provided in such a way that the wedge 232 doesn’t allow angular rotation of the split sector 233 there by upper part 210 when recliner is in lock position.
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[091] Referring to FIG. 10A, the wedge 232 may be provided with a wedge pin 234, in accordance with another embodiment of the present disclosure. The wedge pin 234 is used to drive the wedge 232 during the locking and unlocking of the sector 230. In order to drive the pin 233, the pin 233 may be coupled to the guide plate 240 as shown in FIG. 10B.
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[092] Referring to FIG. 11A, the plurality sector 230 and split sector 233 comprising variable teeth 290 is shown, in accordance with one embodiment of the present disclosure. As known, the variable teeth 290 provided at the plurality sector 230 and split sector 233 are used to lock with upper part teeth 213 provide at the upper part 210. Due to uniformity in 5 profile of the teeth, at times, the teeth 290 get partially locked with the upper part teeth 213 at the upper part 210. In order to overcome the partial locking of the teeth 290 with the upper part teeth 213, the present disclosure discloses providing variable teeth 290.
[093] Referring to FIG. 11B, the variable teeth 290 is explained. As can be seen, at the 10 centre of the plurality sector 230, a plurality of teeth 290 are provided which are uniform. Further, the variable teeth 290 at both sides are gradually reduced such that the radial gap between the variable teeth 290 and the upper part teeth 213 increases gradually at subsequent teeth towards the far end. Further, the parallel gap between the sides of the teeth 290 and the upper part teeth 213 increases gradually at subsequent teeth towards the far end. These 15 variable teeth will improve the possibility of dynamic locking of the recliner and reduces the chances of half or partial locking of first recliner 115 or second recliner 120.
[094] As it is evident from the above disclosure, the recliner assembly can be used to synchronize the operation of the first recliner and the second recliner in lock condition. 20
[095] Further, the cam comprising the cam mould helps in avoiding the noise that is generated when the metals parts come in contact one another.
[096] Further, the cam and sector comprising the dynamic locking surfaces which make the recliner possible to dynamically lock during rotation of upper part.
[097] Further, the cam and sector comprising the safe locking surfaces which make the 25 recliner safe guarded for small unintended rotations of lever.
[098] Further, the cam is designed in such a way that the master legs are in contact with the sectors at all times. Further, the follower legs will have a lag in contact compared with master legs. The cam and sectors design allows translating the force acting on the follower legs onto master legs on the sectors placed in opposition direction. Further, either force is acted on the 30 master leg or follower legs, the cam is in static equilibrium and will be in lock position.
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[099] The wedge is provided to avoid angular rotation of the sector there by upper part at the time of upper part is loaded when recliner is in lock condition. Further, the wedge compensates the tolerances of the lower part, sector and upper and reduces the free play.
[0100] As presented above, the sectors are designed with variable profile such that the radial 5 gap of teeth increases progressively towards the side ends of the sectors. With variable teeth, the sectors get locked properly with the upper part.
[0101] Although implementations of a recliner assembly have been described in language specific to structural features, it is to be understood that the appended claims are not 10 necessarily limited to the specific features described. Rather, the specific features are disclosed as examples of implementations for a recliner assembly for operating a seating unit.
Reference Numerals: 15
Seat Unit 100
Cushion Frame 105
Support Frame 110
First Recliner 115 20
First Adapter 117
Handle Spring 118
Handle Knob 119
Second Recliner 120
Second Adapter 122 25
Connecting Rod 125
Lever 130
Lower Part 205
Synchronization Cavity 206
Upper Part 210 30
Upper Part Teeth 213
Cover Ring 215
Actuator 220
19
Cam 225
Cam Mould 226
Cam Cavity 227
Sectors 230
Wedge 232 5
Split Sector 233
Wedge Pin 234
Internal Spring 235
Guide Plate 240
Sleeve 245 10
Retainer 260
Cam Master leg 271
Cam Master Lock Surface 272
Cam Safe Lock Surface 273
Cam Follower Leg 274 15
Cam Follower Lock Surface 275
Sector Master Leg 280
Sector Master Lock Surface 281
Sector Safe Lock Surface 282
Dynamic Lock Surface 283 20
Sector Follower Leg 285
Sector Follower Lock surface 286
Variable Teeth 290
Contact C
Gap G 25
Gap GG

WE CLAIM:
1. A seat unit (100) for operating a cushion frame (105), comprising:
at least one recliner (115, 120) coupled to the Cushion frame (105), wherein the recliner (115, 120) is operated using a connecting rod (125) coupled to a lever (130); wherein 5 the recliner (115, 120) comprises:
a lower part (205);
an upper part (210);
a cover ring (215) to hold the lower part (205) and the upper part (210);
an actuator (220) coupled to lower part (205) and cam (225); 10
a cam (225) coupled to actuator (220), guide plate (240) and sector (230), wherein the cam (225) is operated upon actuating the lever (130) and wherein the cam (225) comprises a cam master leg (271), a cam master lock surface (272), a cam follower leg (274), a cam follower lock surface (275), and a cam safe lock surface (273); 15
a guide plate (240) coupled to cam (225) and sector (230);
a plurality of sectors (230) coupled to the cam (225), wherein the plurality of sectors (230) is configured to slide radially between a locking position and an unlocking position, wherein each of the sectors (230) comprises a sector master leg (280), a sector follower leg (285), a sector master lock surface (281) provided at the 20 master leg (280), a dynamic lock surface (283), a sector safe lock surface (282) and variable teeth (290);
a split sector (233) coupled to the cam (225) coupled to wedge (232);
a wedge (232) coupled to the cam (225);
characterised in that: 25
forces exerted at the follower leg (285) of the sector (230) is translated to the sector master surface (281) of the master leg (280) of the opposite sector (230) to nullify the forces during the locking position, and forces exerted at the master leg (280) is translated to rotate the cam (225) to move towards locking and make follower leg (285) in contact which nullify the forces on cam. Dynamic locking surface (283) 30 of sector (230) is always in contact with cam during locking which helps to achieve dynamic locking of recliner.
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2. The recliner assembly (115,120) as claimed in claim 1, wherein each of the sectors (230) and split sector (233) comprises variable teeth (290).
3. The recliner assembly (115,120) as claimed in claim 2, wherein the teeth (290) have variable profile to lock the sectors (230) with the upper part (210). 5
4. The recliner assembly (115,120) as claimed in claim 3, wherein the teeth (290) have a progressive radial gap G when coupled with the upper part (210).
5. The recliner assembly (115,120) as claimed in claim 1, wherein one of the sectors 10 (230) comprises a wedge (232).
6. The recliner assembly (115,120) as claimed in claim 5, wherein the wedge (232) is driven by the sector (230) during the unlocking of the sector (230).
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7. The recliner assembly (115,120) as claimed in claim 6, wherein the wedge (232) is provided to compensate tolerance of the lower part (205), upper part (210), sector (230) and prevents angular rotation of the sector (230) when recliner in lock condition.
8. The recliner assembly (115,120) as claimed in claim 7, wherein the wedge (232) 20 comprises a pin (233) coupled to the guide plate (240) to drive the wedge (232).
9. The recliner assembly (115,120) as claimed in claim 1, wherein the cam (225) comprises a cam mould (226) to reduce noise generated when the cam (225) comes in contact with the actuator (220). 25
10. The recliner assembly (115,120) as claimed in claim 1, wherein the lower part (205) comprises a cavity (206) to synchronize the movement of the cam (225) with operation of the lever (130).