WO2012123955A2

WO2012123955A2 - Rear seat back latch

Info

Publication number: WO2012123955A2
Application number: PCT/IN2011/000679
Authority: WO
Inventors: Bijon Nag; Manyam Hemadri Reddy; Muthusamy Ramalingam; Kesavan Rajagopal; Suraj DHARMAVIRA
Original assignee: Ifb Automotive Private Limited
Priority date: 2011-03-15
Filing date: 2011-09-29
Publication date: 2012-09-20
Also published as: WO2012123955A4; WO2012123955A3

Abstract

A connecting element (112) and a latch release assembly (101) for rear seats (102) of an automotive vehicle is described herein. The connecting element (112) has a first coupling portion (118) having an inner cylindrical passage (126). At least one projection (124) is disposed along a first longitudinal axis of the first coupling portion (118). The connecting element (112) has a second coupling portion (120) having a recess (128) along a second longitudinal axis. The first and the second longitudinal axis are inclined to each other. An intermediate portion (122) connects the first (118) and the second coupling portions (120). The latch release assembly (101) has a release cam (113) and a lock cam (114) provided between a base plate (106) and a patch plate (107). The connecting element (112) is detachably disposed between a release member (111) and the release cam (113).

Description

REAR SEAT BACK LATCH

TECHNICAL FIELD

[0001] The present subject matter, in general, relates to foldable rear seats in automotive vehicles, and in particular, relates to a latch release assembly of the foldable rear seats.

BACKGROUND

[0002] Automotive vehicles, especially four wheeled vehicles with different types of rear seating arrangement are known. Customers choose vehicles based on their requirements. Boot space is one of the essential criteria by which vehicles are categorized and chosen. Generally, vehicles that are predominantly used for carriage of goods are categorized as pick-up vehicles. However, these vehicles are mainly used in industries or farmhouses. Non-commercial vehicles that have substantial boot space are categorized as sedan. However, in places having high density of automotive vehicles, customers generally prefer to use hatchbacks to sedans. In these vehicles, rear scats are often located at a close proximity to the vehicle's rear body in such a manner that the top portion of the rear seat is closer to the top portion of the rear body while the bottom portion of the rear seat is farther from the bottom portion of the rear body. This provides a substantial boot space in the area between the bottom portion of the rear seat and that of the rear body. This area is often utilized to accommodate passenger luggage. However, vehicle manufacturers around the world have constantly been working to modify the vehicle design to provide increased boot space for accommodating passenger luggage. One of the recent improvements in this respect is to provide foldable rear seat backs. By providing the foldable rear seat back, the boot space can be temporarily enlarged to accommodate more passenger luggage than the vehicle can ordinarily carry.

SUMMARY

[0003] This summary is provided to introduce concepts related to a latch release assembly and the concepts are further described below in the detailed description. This summary is neither 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. [0004] The connecting element and a latch release assembly for rear seats of an automotive vehicle is described herein. In one embodiment, the connecting element has a first coupling portion having an inner cylindrical passage. At least one projection is disposed along a first longitudinal axis of the first coupling portion. The connecting element has a second coupling portion having a recess along a second longitudinal axis. The first and the second longitudinal axis are inclined to each other. An intermediate portion connects the first coupling portion and the second coupling portion.

BRIEF DESCRIPTION OF THE FIGURES

[0005] The above and other features, aspects and advantages of the subject matter will be better understood with regard to the following description, appended claims, and accompanying drawings, where:

[0006] Figure 1(a) and 1(b) depicts a schematic illustration of rear seat back with latch release assembly mounted on the seat, in accordance with an embodiment of the present subject matter.

[0007] Figure 2 shows an exploded view of the latch release assembly, in accordance with an embodiment of the present subject matter.

[0008] Figure 3(a) and 3(b) shows a schematic view of the lever rod clip of the latch release assembly, in accordance with an embodiment of the present subject matter.

[0009] Figure 4 shows a schematic view of the lever rod sub-assembly of the latch release assembly, in accordance with an embodiment of the present subject matter.

[0010] Figure 5(a) and 5(b) shows a schematic view of the latch release assembly in latched and delatched conditions, in accordance with an embodiment of the present subject matter.

DETAILED DESCRIPTION

[0011] The subject matter described herein relates to a latch release assembly, and in particular, to a connecting element of the latch release assembly. [0012] Generally, foldable rear seat backs are attached to the rear body of the vehicle such that they remain stable without causing any vibratory disturbances to the occupant of the rear seats. The seats are attached to the vehicle body in a number of known manners. One of the known methods includes attaching the rear seat back centrally to the rear frame of the vehicle through an intermediate member that is fixed permanently to the frame. In this method, the rear seat back is releasably latched to the intermediate member fixed to the frame. These latching mechanisms use cables for releasing the latch, which are accessible only from the boot space of the vehicle. The position of the intermediate member is so located that the occupants of the rear seats of the vehicle cannot access it.

[0013] The conventional systems that followed solved the issue of location of latching mechanisms by providing the latch location on the seat back instead of the intermediate member. This had various advantages associated with it. Firstly, the location of the latch is such that the rear seat occupant can easily access it. Secondly, it provided the seat backs to be firmly positioned in an upright position when latched to the rear frame, which allowed them to resist the vibrations caused due to the luggage placed in the boot.

[0014] Further developments as far as the positioning of the latch mechanisms have seen the latch mechanism being positioned at various locations on the rear seat backs. The latch mechanisms of the past had to resolve issues other than providing an optimum location. The type of latch mechanism employed is an important issue. The generally known latch mechanisms includes cable release type latching, push down plunger type latching, rigid/flexible cloth tethers and release lever type latching. Each of the conventionally known set-ups had their own advantages and limitations.

[0015] The release lever type latching mechanism involves a release lever operationally engaged through a plurality of cams to engage and disengage so as to latch or delatch the cams from a striker or an anchor that is fixed to the vehicle rear frame. This provides an easy operation of latching and delatching of the rear seats from the rear frame by a simple movement of the release lever, which is located at an optimum position making it easily accessible. This mechanism functions by engaging and disengaging the release lever with one or more cams. The release lever is generally fixed permanently with one of the cams either by a riveting process or by any other known permanent fixing mechanisms. Riveting is the commonly used technique in this process as both the lever and the cam are made of metal and can be easily riveted to form a single unit along with the other joining components. However, any damage to the unit usually caused due to wear and tear of the components involves the total unit being replaced, as it is not possible to differentiate the worn out component from the normally functioning components due to riveting of the components. Further, the metal-to-metal contact between the release lever and the cams also generate frictional noise that adds to the wear and tear of the components. This type of arrangement also involves greater play in the assembly, which affects the life of the entire assembly.

[0016] The present subject matter provides a latch release assembly that is mounted onto the rear seat. The latch release assembly of the present subject matter is mounted at an optimum location so that the rear seat can be easily latched and delatched from the rear frame of the vehicle. The latch release assembly includes a release member, also interchangeably called as a lever rod, for latching and delatching the assembly with the rear frame. The rear frame of the vehicle is provided with a striker or an anchor that engages with the latch release assembly. The lever rod is operably coupled to a release cam through a connecting member. The connecting member is interchangeably called as a lever rod clip. The lever rod clip acts as a connecting member between the lever rod and the release cam. The lever rod clip enables easy assembly of the lever rod with the release cam. The connecting member is snap fitted to the release cam by means of at least one projection. The lever rod end passes through the lever rod clip and is coupled to the release cam. The snap fit arrangement of the lever rod clip and the release cam ensures that the lever rod and the release cam can be decoupled without difficulty. This also helps in easily locating the worn out component and replacing it without having to replace the entire lever rod sub-assembly.

[0017] The latching and delatching operation of the latch release assembly includes manually pulling the lever rod from its original position and releasing the assembly from the striker. The assembly is releasably latched to the striker by means of a lock cam, which is rotated about the longitudinal axis of the seat for latching and delatching the assembly from the striker.

[0018] In one embodiment, the lever rod clip is made of a plastic material. This prevents metal-to-metal contact of moving parts, thereby substantially reducing the wear and tear of the lever rod and the release cam. This also substantially reduces the noise generated during the operation of the lever rod. The lever rod clip acts as a connecting element between the lever rod and the release cam and prevents the contact between them.

[0019] Figure 1 (a) and 1(b) depicts a schematic illustration of a rear seat back with latch release assembly 101 that is mounted on to a rear seat 102 of an automotive vehicle. The rear seat 102 is provided with a seat bottom 104 and a seat back 103. The seat back 103 is pivotall supported by the seat bottom 104 and is capable of being switched from a normal upright position to a folded position. The seat back 103, while in folded position, provides for a larger storage space. This storage space, in addition to the storage space available in the vehicle boot, provides additional storage capacity.

[0020] In an embodiment, the latch release assembly 101 is preferably mounted at the top corner side of the seat back 103. It should be noted that the latch release assembly 101 can be mounted to either or both ends of the seat back 103. It should also be noted that in another embodiment there can be two separate rear seats 102 and the latch release assembly 101 can be mounted to the seat back 103 of any one of the rear seats 102 or to both the rear seats 102 at the preferred location. In another embodiment, the latch release assembly 101 can also be disposed at an alternate optimum location on the seat back 103 such as the backside of the seat back 103.

[0021] A striker 105, also called as an anchor, is secured to the inner side of a rear frame

140 of the automotive vehicle. The striker 105 is located in such a manner that it remains in proximity to the seat back 103 when the seat back 103 is in an upright position. In the normal upright position of the seat back 103, the latch release assembly 101 engages with the striker 105 in a latched position. In an embodiment, the latch release assembly 101 includes a release member 1 1 1 also interchangeably called as a lever rod 1 1 1 connected to a release cam (not shown in this figure) through a connecting element (not shown in this figure). The release member 1 1 1 is operable by a user to release the latch release assembly 101 from the striker 105 and to position the seat back 103 in a folded position. It should be noted that the release member 1 1 1 can be a flexible lever or a lever cable or any other mechanical means that makes use of a spring action to engage and disengage the seat back 103 with the striker 105 in another embodiment of the present subject matter. [0022] Figure 2 shows an exploded view of the latch release assembly 101 , in accordance with an embodiment of the present subject matter. The latch release assembly 101 includes a base plate 106 and a patch plate 107. The base plate 106 is mounted on to the seat back 103. The patch plate 107 is mounted in such a manner as to act as a housing along with the base plate 106 for the various components of the latch release assembly 101 . A rubber holder 109 and a rubber stopper 1 10 are connected to the base plate 106. The rubber holder 109 and the rubber stopper 1 10 acts as a damping member between the latch release assembly 101 and the striker 105 during the latching and delatching operations. The lever rod 1 1 1 is connected to a release cam 113 through a connecting element 1 12, which is interchangeably called as a lever rod clip 3 12. The release cam 1 13 rotatably abuts a lock cam 1 14.

[0023] In an embodiment, the release cam 1 13 is rotatably hinged to the base plate 106 at an end 130 of the release cam 1 13. In another embodiment, the release cam 1 13 can be hinged by any other hinging mechanisms such as cylindrical pins, grooved pins, cylindrical shafts, and threads. At another end 132, the release cam 1 13 receives the lever rod 1 1 1 through the lever rod clip 1 12. At a peripherally disposed edge 134 closer to the end 132 and farther from the end 130, the release cam 1 13 abuts the lock cam 1 14. The edge 134 of the release cam 1 13 abuts the lock cam 1 14 at a slot 136 on the periphery of the lock cam 1 14. The meshing between the cams 1 13 and 1 14 occurs when the latch release assembly 101 is in the latched condition. The lock cam 1 14 is rotatably hinged to the base plate 106 and the patch plate 107 through another shaft cam 1 16 and adapted to mesh with the release cam 1 13 at an end 138. Both the shaft cams 1 16 includes external bearing surface about which the adjoining components rotate. Further, the lock cam 1 14 is hinged to a spring cam 1 15, which is mounted on to one end of a lever spring 108. The lever spring 108 is hooked to the lever rod 1 1 1 such that the reciprocating movement of the lever rod 1 1 1 effects a rotational movement of the release cam 1 13 and the lock cam 1 14 during the latching and delatching operation of the latch release assembly 101. The back plate 106 and the patch plate 107 are axially spaced apart by a spacer 117 that prevents any sort of contact between these plates 106 and 107. The base plate 106 and the patch plate 107 include recesses to receive the striker 105 during the latching and delatching operation of the latch release assembly 101. [0024] Figure 3(a) and 3(b) shows a schematic view of the lever rod clip 1 12 of the latch release assembly 101 , in accordance with an embodiment of the present subject matter. The lever rod clip 1 12 comprises a first coupling portion 1 18, a second coupling portion 120 and an intermediate portion 122. The lever rod clip 1 12 or otherwise called as the connecting element 1 12 connects the lever rod 1 1 1 with the release cam 1 13. In an embodiment, the lever rod 1 1 1 and the release cam 1 13 are made of metal. In an embodiment, the lever rod clip 1 12 is made of a plastic material. The presence of the lever rod clip 1 12 ensures that the lever rod 1 1 1 is not directly attached to the release cam 1 13 and thereby eliminating the metal-to-metal contact between the lever rod 1 1 1 and the release cam 1 13.

[0025] In an embodiment, the first coupling portion 1 18 of the lever rod clip 1 12 is cylindrical. In another embodiment, the first coupling portion 1 18 can be of any solid shape, such as cubical or conical. In another embodiment, the first coupling portion 1 18 is hollow and has an inner cylindrical cavity 126 to receive the lever rod 1 1 1. In an embodiment, the second coupling portion 120 has a rectangular cross-section. The second coupling portion 120 has a recess 128 along a second longitudinal axis to receive the lever rod 1 1 1. The second coupling portion 120 arrests the reciprocal movement of the lever rod 1 1 1 beyond a certain position by receiving the lever rod in the recess 128.

[0026] In an embodiment, the first coupling portion 1 18 has one or more projections 124 along the longitudinal axis of the first coupling portion 1 18 with at least one slit 142. The projection 124 is further provided with lips 144. The lips 144 along with the slit 142 provide the required spring action for establishing a snap fit with an aperture near the end 132 of the release cam 1 13. In another embodiment, there can be a single circular projection 124 with partial slits provided across the circumference of the projection 124. The extended surfaces on the projections 124 causes the projection 124 to snap fit with the release cam 1 13. The first coupling portion 1 18 and the second coupling portion 120 are connected by an intermediate portion 122, which is a flat planar surface disposed at a predetermined angle. In an embodiment, the predetermined angle can be in a range of about 0° to 45°. The first coupling portion 1 18 and the second coupling portion 120 are disposed in such a manner that the first longitudinal axis of the first coupling portion 1 18 and the second longitudinal axis of the second coupling portion 120 are inclined to each other. In an embodiment, they are inclined at an angle of about 90° to 150°. [0027] Figure 4 shows a schematic view of the lever rod sub-assembly of the latch release assembly, in accordance with an embodiment of the present subject matter. The lever rod clip 1 12 is connected to the release cam 1 13 through an aperture in the release cam 1 13. In an embodiment, the lever rod clip 1 12 is snap fitted to the release cam 1 13 through the one or more projection 124. After connecting the lever rod clip 1 12 with the release cam 1 13, the lever rod 1 1 1 is attached to the release cam 1 13 through the first coupling portion 1 18 of the lever rod clip 1 12. The recess 128 in the second coupling portion 120 of the lever rod clip 112 is adapted to receive the lever rod 1 1 1.

[0028] The lever rod 1 1 1 is connected to the release cam 1 13 through the first coupling portion 1 18 of the lever rod clip 1 12. This enables the release cam 113 to be operated with substantially reduced lateral play during the latching and delatching operations. In this arrangement, the reciprocal cooperation achieved between the lever rod 1 1 1 , the lever rod clip 112, and the release cam 1 13 enables enduring operation of the latch release assembly 101 without adopting to any external joining mechanisms such as a riveting mechanism. This also enables the latch release assembly 101 to operate with a substantially reduced frictional noise. In another embodiment, the lever rod clip 112 and the release cam 1 13 can be coupled by other alternate methods that serve the function of flexible mating of the lever rod clip 1 12 with the release cam 1 13. The lever rod clip 1 12 between the lever rod 1 11 and the release cam 1 13 also ensures ease of assembly and replacement of worn out components.

[0029] In the latch release assembly 101 of the present invention the cooperating arrangement among the lever rod 1 1 1 , lever rod clip 1 12 with the release cam 1 13 is without a metal-to-metal contact. This substantially eliminates the generation of noise from the assembly 101. In addition, the latch release assembly 101 of the present subject matter also eliminates the process of flaring or crimping.

[0030] Figure 5(a) and 5(b) shows a schematic view of the latch release assembly 101 in latched and delatched conditions, respectively, in accordance with an embodiment of the present subject matter. In the latched condition, the latch release assembly 101 is engaged with the striker 105, which is secured to the inner surface of the rear frame 140 of the automotive vehicle. While, in the delatched condition, the latch release assembly 101 is disengaged from the striker 105 to facilitate the folding of the rear seat back 103. [0031] In order to effect the delatching of the latch release assembly 101 from the striker

105 and switch the rear seat 102 from the upright position to a folded position, the lever rod 1 1 1 is pulled in a direction away from the striker 105. This causes the release cam 1 13 to slide in a direction towards the lever rod 1 1 1. This in turn causes the edge 134 of the release cam 1 13 to mesh away from the slot 136 of the lock cam 1 14 thereby release the lock cam 1 14 to rotate freely from its locked condition. This also enables the lock cam 1 14 to rotate in a downward direction thereby freeing the striker 105 and releasing the latch release assembly 101.

[0032] In order to effect the latching of the latch release assembly 101 with the striker

105, the lever rod 1 1 1 is pulled in a direction away from the striker 105 after bringing the rear seat 102 to an upright position. The lever spring 108 causes the lock cam 1 14 to remain in its original position and does not allow rotating until actuated by the lever rod 1 1 1. Further, the lever spring 108 also provides the necessary spring action to the lock cam 1 14 to engage with the striker 105. In an embodiment of the present subject matter, latching of the latch release assembly 101 with the striker 105 is effected by pressing the lock cam 1 14 against the striker 105 causes the latch release assembly 101 to engage with the striker 105. In another embodiment, the latching can be effected manually by operation of the lever rod 1 1 1. After bringing the rear seat 102 to the upright position, the lever rod 1 1 1 can be pulled in a direction away from the striker 105. This causes the lock cam 1 14 to rotate and accommodate the striker 105 and enable the lock cam 1 14 to engage with the striker 105. The striker 105 is held by the lock cam 1 14, the latch release assembly 101 attains the latched condition.

[0033] The lever rod clip 1 12 between the lever rod 1 1 1 and the release cam 1 13 ensures that the frictional noise generated during the latching and delatching operation of the latch release assembly 101 because of the rotational operation of the lever rod and the release cam 1 13 is substantially eliminated.

[0034] Although embodiments for a connecting element and a latch release assembly for rear seats of an automotive vehicle have been described in language specific to structural features and/or methods, it is to be understood that the invention is not necessarily limited to the specific features or methods described. Rather, the specific features and methods are disclosed as exemplary embodiments for a connecting element and a latch release assembly for rear seats of an automotive vehicle.

Claims

I /We claim:

1. A connecting element (1 12) comprising:

a first coupling portion (1 18) having an inner cylindrical passage (126), wherein at least one projection (124) is disposed along a first longitudinal axis of the first coupling portion (1 18);

a second coupling portion (120) having a recess ( 128) along a second longitudinal axis, wherein the first longitudinal axis of the first coupling portion (1 18) and the second longitudinal axis of the second coupling portion ( 120) are inclined to each other; and an intermediate portion ( 122) connecting the first coupling portion (1 18) and the second coupling portion (120).

2. The connecting element (1 12) as claimed in claim 1 , wherein the first coupling portion (1 18) is adapted to receive a release member ( 1 1 1 ) of a latch release assembly (101 ).

3. The connecting element (1 12) as claimed in claim 1 , wherein the at least one projection (124) is adapted to snap fit with a release cam (1 13) of a latch release assembly ( 101 ).

4. The connecting element (1 12) as claimed in claim I , wherein the intermediate portion (122) is disposed at an angle of about 0° to 45° with respect to a horizontal plane of the connecting element (1 12).

5. The connecting element (1 12) as claimed in claim 1 , wherein the first longitudinal axis of the first coupling portion (1 18) and the second longitudinal axis of the second coupling portion are inclined at an angle of about 90° to 150°.

6. The connecting element (1 12) as claimed in claim 1 , wherein the connecting element (1 12) is a lever rod clip made from a plastic material.

7. A latch release assembly (101 ) for rear seats of an automotive vehicle comprising:

a base plate (106) for mounting on the rear seat of the vehicle;

a patch plate ( 107) coupled to the base plate ( 106) to encapsulate a plurality of components of the latch release assembly (101);

a release cam (1 13) rotatably hinged to the base plate (106) and the patch plate (107) at one end (130);

a lock cam (1 14) rotatably hinged to the base plate (106) and the patch plate (107) and adapted to mesh with the release cam (1 13) at an end (138); and a connecting element (1 12) detachably disposed between a release member ( 1 1 1 ) and the release cam (1 13).

8. The latch release assembly (101) as claimed in claim 7, wherein the connecting element (1 12) comprises a first coupling portion (1 18), a second coupling portion (120) and an intermediate portion (122).

9. The latch release assembly (101 ) as claimed in claim 8, wherein the first coupling portion comprises at least one projection (124) attached to the release cam (1 13).

10. The latch release assembly (101) as claimed in claim 7, wherein the release cam ( 1 13) has an edge (134) peripherally disposed at a region farther from the end (130) and closer to an end (132) that meshes with a slot (136) on the periphery of the lock cam (1 14) when the latch release assembly (101) is in locked condition.

1 1. The latch release assembly (101) as claimed in claim 7, wherein the assembly (101 ) comprises at least two shaft cams (1 16) for rotatably hinging the release cam (1 13) and the lock cam (1 14) between the base plate (106) and the patch plate (107).

12. The latch release assembly (101 ) as claimed in claim 7, wherein the assembly ( 101 ) comprises a spring shaft (1 15) that couples a lever release spring ( 108) with the lock cam (1 14) through the base plate (106).

13. The latch release assembly (101) as claimed in claim 7, wherein the assembly ( 101 ) comprises a plurality of damping members (109, 1 10) for reducing noise generated during latching and delatching of the assembly (101 ) with a striker (105).

14. The latch release assembly (101) as claimed in claim 7, wherein the assembly (101) comprises a spacer ( 1 17) that separates the base plate (106) and the patch plate ( 107).

15. The latch release assembly (101 ) as claimed in claim 7, wherein the release member (1 1 1) is a lever rod that is operated during latching and delatching of the assembly ( 101 ) from a striker (105) that is fixed to the rear frame of the vehicle.

16. The latch release assembly (101 ) as claimed in claim 8, wherein the release member (1 1 1) is detachably coupled to the release cam (1 13) through an inner cylindrical passage (126) of the first coupling portion (1 18) of the connecting element (1 12).