Center armrest inertial lock

An inertial lock assembly for a vehicle armrest includes a stopping member disposed on an armrest attachment bracket and a catch pin for engaging the stopping member. The catch pin is disposed on an armrest link journaled at one end to the attachment bracket and at an opposed end to an armrest frame. The stopping member pivots to engage the catch pin. A guide pin disposed on the armrest attachment bracket is configured to slide within an arcuate guide slot in the stopping member, to restrict a range of pivoting movement of the stopping member. A stop disposed on the armrest link is configured to bias an end of the arcuate guide slot against the guide pin when the armrest attachment bracket and armrest link are in a stowed configuration or in a fully deployed configuration. Armrest and seat assemblies including the inertial lock assembly are described.

TECHNICAL FIELD

This disclosure relates generally to seats for motor vehicles, and more particularly to a locking mechanism for a seat center armrest.

BACKGROUND

Center seat armrests are well known in the art, and are used particularly with motor vehicle bench-type seats. The center seat armrest, as the name implies, provides a convenient place in a center portion of a seat for a passenger to rest his or her arm. Moreover, center seat armrests may be equipped with a variety of useful and convenient features such as storage bins, cup holders, and the like. Typically, a center seat armrest is configured to pivot, allowing the armrest to be translated between a stowed configuration (usually at least partially or fully nested within a recess in the vehicle seat back whereby a seat back for a passenger is provided) and a deployed, substantially horizontal configuration for use by adjacent passengers.

To deploy the armrest, usually it is necessary only to grasp the armrest or a handle attached to the armrest and pull forward. That is, for convenience the user typically does not have to actuate a dedicated locking/unlocking mechanism in order to use the armrest. Instead, a friction fit between the armrest and a receiver defined in the seat back is most often relied on to keep the armrest in a stowed configuration. However, while convenient, this admits of inadvertent and undesired deployment of the armrest. For example, this could be caused by vehicle deceleration created by a frontal impact to the vehicle, causing an otherwise unrestrained center armrest to deploy.

To solve this and other problems, the present disclosure relates to a vehicle seat center armrest inertial lock configured to retain the center armrest substantially in a stowed configuration in the event of a frontal impact to the vehicle. Advantageously, the inertial lock allows normal deployment of the center armrest by a user, without requiring the user to actuate a locking/unlocking mechanism. However, in the event of a frontal impact to the vehicle, the inertial lock prevents inadvertent and undesired deployment of the armrest caused by the forward inertial energy of the impact.

SUMMARY

In accordance with the purposes and benefits described herein, in one aspect an inertial lock assembly for a vehicle armrest is provided, the inertial lock assembly including a stopping member disposed on an armrest attachment bracket. A catch pin for engaging the stopping member is provided, the catch pin being disposed on an armrest link journaled at one end to the armrest attachment bracket and at an opposed end to an armrest frame. During a sudden vehicle deceleration, for example an acute braking operation or a frontal impact to the vehicle, the stopping member freely pivots. In embodiments, the stopping member includes an arcuate guide slot. A guide pin disposed on the armrest attachment bracket engages the arcuate guide slot, thereby restricting a range of pivoting movement of the stopping member.

The inertial lock assembly may also include a stop disposed on the armrest link. The stop is configured to bias an end of the arcuate guide slot against the guide pin when the armrest attachment bracket and armrest link are in a stowed configuration or in a fully deployed configuration. In embodiments, the stop is a bar attached to the armrest link and having a pair of biasing members disposed at an end thereof. In alternative embodiments, the stop is provided by a pair of biasing members disposed at an end of the armrest link.

In another aspect, an armrest assembly for a vehicle including the inertial lock assembly described above is provided. In yet another aspect, a seat assembly for a vehicle is provided, including the armrest assembly and the inertial lock assembly.

In the following description, there are shown and described embodiments of the disclosed vehicle seat center armrest inertial lock. As it should be realized, the inertial lock is capable of other, different embodiments and its several details are capable of modification in various, obvious aspects all without departing from the devices and methods as set forth and described in the following claims. Accordingly, the drawings and descriptions should be regarded as illustrative in nature and not as restrictive.

Reference will now be made in detail to embodiments of the disclosed vehicle center armrest inertial lock, examples of which are illustrated in the accompanying drawing figures.

DETAILED DESCRIPTION

FIG. 1shows an exemplary seat assembly10for a vehicle, in the depicted embodiment being a partial view of a bench-type second row vehicle seat12including a pivoting 60% seat center armrest14. The seat12, as is well known in the art, is defined by a frame (not visible in this view) defining a seat bottom16having seating areas for a plurality of passengers, a seat back18, padding for passenger comfort, a cover, and fixed or deployable headrests20. As shown, armrest14is in an upright, stowed configuration within a cavity22defined in the seat back18. For convenience, only a left and a center seating area of seat12are depicted, although as is known a right seating area will also be included in the conventional bench-type vehicle seat10. It will be appreciated also that this embodiment is depicted for illustrative purposes only, and that the various structures and embodiments described below are equally adaptable to alternative vehicle seat types.

FIG. 2shows an isolated view of a pivoting center armrest14according to the present disclosure, including an armrest body24configured for pivoting relative to the seat back18(not shown in this view) for translation between an upright, stowed configuration and a fully deployed configuration for use as an armrest. An attachment bracket26secures the armrest body24to the seat frame or to a frame member of the vehicle body (not shown in this view). At least one link28is included, journaled at a first end to the attachment bracket26and at a second end to a portion of the armrest body24. In the depicted embodiment, a lower link28and an upper link28′ are provided. The links28,28′ may in embodiments be journaled to a frame member defining the armrest14, to brackets attached to sides of the armrest body24, or otherwise. At least one inertial lock assembly30is included, the structure and purpose of which will be described in greater detail below. As will be appreciated, in embodiments a single inertial lock assembly30may be provided. In alternative embodiments, a pair of inertial lock assemblies30may be provided, disposed at opposed corners of the armrest body24.

An inertial lock assembly30according to the present disclosure is shown in isolation inFIG. 3A, in the depicted embodiment being attached to an armrest body24held in an upright, stowed configuration. The inertial lock assembly30includes a pivoting stop member32disposed on attachment bracket26for freely pivoting about an axis34. In the depicted embodiment, stopping member32defines a pivoting hook structure configured at an end36to engage a catch pin38. A stop40is included, in the depicted embodiment being secured to lower link28and including a pair of biasing members42,42′ configured to contact an end44of stopping member32. Stopping member32also includes an arcuate guide slot46defined in a portion thereof. A guide pin48extending from or attached to attachment bracket26is configured to pass through guide slot46. In combination, guide slot46and guide pin48restrict a range of pivoting movement of stopping member32.

FIG. 3Bshows the inertial lock assembly30ofFIG. 3A, with the catch pin38head removed for clarity. In the depicted embodiment, stop40is attached to lower link28whereby when link28pivots, stop40will concurrently pivot. As shown, biasing member42′ is in contact with end44of stopping member32, biasing stopping member32forward whereby an end of guide slot46is urged against guide pin48. Likewise, on pivoting the armrest body24to a fully deployed configuration, link28and therefore stop40will likewise pivot, whereby biasing member42will contact the end44of stopping member32, biasing stopping member32whereby an opposite guide slot46is urged against guide pin48. It will be appreciated that by this structure stopping member32is prevented from rattling despite its configuration for freely pivoting about axis34.

Turning now toFIGS. 4A-4D, operation of the inertial lock assembly30during normal deployment of an armrest (not shown), i.e. when a passenger pivots the armrest from an upright and stowed configuration (FIG. 4A) to a fully deployed configuration (FIG. 4D), will now be shown and described. As described above, in the upright and stowed configuration ofFIG. 4Abiasing member42′ of stop40is in contact with end44of stopping member32, biasing stopping member32forward whereby guide pin48is urged against an end of guide slot46. The inertial lock assembly30is configured whereby during normal deployment of the armrest such as by a passenger, as attachment bracket26and lower link28pivot relative to one another, stopping member32does not contact catch pin38(seeFIGS. 4B and 4C) and so translation of the armrest to the fully deployed configuration (FIG. 4D) is allowed without requiring any type of specific lock release mechanism. That is, the force of gravity (see arrows) preserves the orientation of the stopping member32, allowing the catch pin38to disengage from the stopping member32.

As attachment bracket26and lower link28pivot, guide pin48travels through guide slot46. Concurrently with the pivoting of lower link28, stop40pivots whereby biasing member42contacts end44of stopping member32, urging an opposed end of guide slot48against guide pin46. As described above, this prevents free motion of stopping member32when the armrest is in the fully upright stowed configuration or in the fully deployed configuration, eliminating annoying rattling of stopping member32and other noise.

On the other hand, as shown inFIG. 5, in the event of a sudden vehicle deceleration such as an emergency braking action, a frontal impact to the vehicle, or the like, because the stopping member32is configured to freely pivot about axis34the effect of gravity on the stopping member32will be temporarily counteracted and the stopping member32will be urged forward by the deceleration force (see arrow) to preserve the engagement of catch pin38. By this mechanism, deployment of the armrest during a sudden deceleration of the vehicle (in a non-limiting example a deceleration exceeding 1 G (9.81 m/s2)) is prevented.

An alternative embodiment of the inertial locking assembly30is shown inFIG. 6. As depicted, upper link28′ and lower link28are journaled at a first end to an attachment bracket26and at a second end to an armrest frame50. Rather than including a separate stop40as described above, biasing members52,52′ are disposed on an end of lower link28. The operation of this alternative embodiment is substantially as described above. During normal deployment of the armrest (FIGS. 7A, 7B), the force of gravity (see arrow) allows the stopping member32to pivot away from the catch pin38, preventing stopping member32from engaging catch pin38. On the other hand, as shown inFIGS. 8A and 8B, in the event of a sudden vehicle deceleration the freely pivoting stopping member32will be urged to pivot in a clockwise rotation, preserving the engagement of the stopping member32and the catch pin38.

The benefits of the presently disclosed inertial locking assembly30are apparent. A relatively uncomplex and robust locking mechanism is provided for preventing inadvertent deployment of a center seat armrest during vehicle deceleration. The inertial locking assembly30allows normal deployment of the armrest by a passenger, without requiring any specific lock release mechanism is required. Obvious modifications and variations are possible in light of the above teachings. All such modifications and variations are within the scope of the appended claims when interpreted in accordance with the breadth to which they are fairly, legally and equitably entitled.