Seat assembly having a movable head restraint

A vehicle head restraint assembly is provided with a first guide member mounted proximate to a vehicle seat back and a second guide member mounted to the first guide member for movement in fore and aft direction. One of the guide members has a series of notches. A head restraint is mounted to the second guide member. A locking mechanism is mounted to the other guide member for extending into one of the notches. A biasing member biases the locking mechanism in engagement with the notches. An actuator is mounted to one of the guide members for actuation from one lateral side of the head restraint and cooperates with the locking mechanism such that linear actuation of the actuator from one lateral side results in symmetrical compression of the biasing member for disengaging the locking mechanism from the notches for permitting fore and aft adjustment of the head restraint.

BACKGROUND

1. Technical Field

Various embodiments relate to a vehicle seat assembly having a movable head restraint.

2. Background Art

Movable head restraints permit adjustment of a head restraint relative to the seat assembly. One such example is disclosed in U.S. Pat. No. 7,073,863 B1 to Low et al.

DETAILED DESCRIPTION

Referring toFIG. 1, a movable head restraint assembly30is shown. The head restraint assembly30may be provided with a seat assembly, as illustrated by a seat back32inFIG. 1. The seat assembly may be a seat for a vehicle, such as a vehicle like a car or truck.

The movable head restraint assembly30may include a support post34and a headrest36.

The support post34may extend from the seat back32of the vehicle seat. The support post34may be fixedly or movably disposed on the seat back32in various embodiments. The support post34may be disposed in a guide sleeve that is disposed on the seat back32. The support post34may have any suitable configuration. For example, one or more support posts34may extend between the seat back32and the headrest36. Moreover, the support post34may be generally U-shaped. The support post34may be made of any suitable material or materials such as a metal or metal alloy. The support post34may also be mounted directly to the vehicle body proximate to the vehicle seat back32.

The headrest36may include a trim cover38(FIG. 4), a cushion40and a positioning apparatus42. The headrest36may be configured to support the head of a seat occupant and move in one or more directions with respect to the support posts34.

The trim cover38may provide at least a portion of the exterior of the headrest36. The trim cover38may be made of any suitable material or materials, such as vinyl, leather, fabric, or combinations thereof.

The cushion40may be disposed proximate and may be concealed by the trim cover. The cushion40may be made of any suitable material or materials. For example, the cushion40may be an opened or closed cell foam.

Referring toFIG. 4, the headrest36may also include a front shell44and a back shell46. The front and back shells44,46may be disposed at least partially inside the trim cover38and or foam40. The front and back shells44,46may provide a support structure and may include openings that face toward each other. The front and back shells44,46may engage or interlock with each other. The back shell46may include one or more posts48that extend toward and may engage corresponding posts49(FIGS. 8 and 9) of the front shell44. The front shell44may be similarly configured.

For the depicted embodiment, the back shell46includes an array of posts48with an upper central post48and a pair of lower laterally spaced posts48. Each of the posts48may have any suitable guide configuration. For the depicted embodiment, the upper post48is generally rectangular; and the lower posts48each include a bevel removing an outboard corner of the otherwise rectangular profile to facilitate with guidance and assembly of a corresponding guide member. Additionally, each of the posts includes a series of notches50formed therein spaced incrementally in an axial direction of the posts48. The posts49of the front shell44are similarly configured and may include a series of notches51.

A traverse member52may be disposed on the seat back32. The traverse member52may be at least partially disposed in the headrest36and/or front and back shells44,46.

The traverse member52also includes a traverse rear shell54and a traverse front shell56for mounting upon the support post34and for retaining components of the positioning apparatus42. The traverse rear and front shells54,56may be configured to be assembled together. Each of the traverse rear and front shells54,56include an array of sleeves58,60that are sized to receive the posts48,49of the back shell46and the front shell44, respectively. Each of the sleeves58,60may include a plurality of bar guides each provided about the periphery for reducing friction resistance. Additionally, a plurality of slide members or sliders62may be provided each extending through a pair of sleeves58,60of the traverse rear and front shells54,56for providing uniform contact along the posts48of the back shell46and the posts49of the front shell44. The sliders62may be formed of a material having a reduced coefficient of friction than that of the structural material, such as a polymeric material, that may be employed for the traverse rear and front shells54,56. In at least one embodiment, the sliders62may be fixedly disposed on or integrally formed with the traverse member52. Alternatively, the sliders62may also be formed as sleeves and each may receive an associated post48. Alternatively, the sliders62may be omitted in one or more embodiments. Additionally, the sliders62may operate as springs. In case of manual adjustment with one hand, a forward or rearward force may be applied to one lateral side of the headrest36. The sliders62can build up back pressure to result in linear actuation without canting or binding.

The front shell44and the back shell46are mounted for movement in a fore and aft direction upon the traverse member52. The front and rear shells44,46support the cushion40and trim cover38of the headrest36. The positioning apparatus42limits movement of the front and rear shells44,46, and consequently movement of the cushion40and the trim cover38relative to the traverse member52for permitting fore and aft adjustment of the headrest36relative to the post34and consequently the seat back32.

The support post34may include a pair of intermediate fore and aft portions64, which extend through the headrest36. In one embodiment, a pair of rings66are mounted to the rear shell46and are utilized for mounting the trim cover38to the rear shell46while providing an opening in the trim cover38for the intermediate portions64of the support post34to extend through. In other embodiments, the rings66may not be necessary.

The positioning apparatus42is actuated by a manual button68, which may be provided to facilitate locking or unlocking of the positioning apparatus42. The button68may be received within a sleeve70of the front shell44.

The button68may actuate a lever, such as a push rod72. The push rod72may have any suitable configuration. The push rod72may be configured to move or actuate an interlocking member74. In at least one embodiment, the push rod72may include an end feature that engages mating features on the interlocking member74. The end feature may be generally triangular and may move in a first direction or manner. Movement of the end feature may cause the interlocking member74to move in a second direction or second manner. The first and second directions may be substantially perpendicular or may be along substantially perpendicular axes or planes. The push rod72may be spaced apart from or may be configured to move with respect to when one of the front and back shells44,46is actuated.

A bevel ring76may be provided through an opening in the trim cover38and cushion40and mounted to the sleeve70of the front shell44for enclosing an opening through the trim cover38and the cushion40while permitting access to the button68. A coil spring78may be provided between the button68and the bevel ring76for actuating the button68to a locked position of the interlocking member74. Thus the user may be required to overcome a bias provided by the coil spring78when actuating the button68for consequently actuating the push rod72and the interlocking member74.

FIG. 5illustrates a rear side of the traverse rear shell54. A rotary actuator80is pivotally connected to the traverse rear shell54. The rotary actuator80includes an radially offset pin82extending therefrom for engagement with the push rod72. The push rod72includes a first end84pivotally connected to the button68. An output end of the push rod72includes a pair of inclined surfaces86that collectively provide a concaved surface86for receiving the pin82. Therefore linear movement of the button68provides linear movement of the first end84of the push rod72, which consequently causes the radially offset pin82to rotate about a center of the rotary actuator80. Thus the push rod72is translated and pivoted at both ends as the rotary actuator80is rotated.

The push button68is mounted to the front shell44and translates with the front shell44relative to traverse member52, and consequently the push rod72. Therefore, the input end84of the push rod72extends in the fore and aft direction as illustrated inFIG. 4, for receiving an input force from the push button68at various positions of the push button68.

FIGS. 6 and 7illustrate a front surface of the traverse front shell56. The rotary actuator80is connected for rotation with a cam88. The interlocking part74may be received by the traverse member52. The interlocking part74may be received in slots90,92in the traverse member52and may be configured to move with respect to the traverse member52. The interlocking member74may be configured to engage the front and/or back shells44,46or one or more posts48,49to permit movement of the front and rear shells44,46and the headrest36with respect to the traverse member52and the support post34. The interlocking member74may be configured to disengage the front and back shells44,46or one or more posts48,49to permit movement of the front and rear shells44,46and the headrest36with respect to the traverse member52and the support post34. The interlocking member74may have any suitable configuration. In at least one embodiment, the interlocking member74may be configured with a pair of elongate arms94,96that are spaced apart from each other when in an extended or locking position as illustrated inFIG. 6. The locking arms94,96may be moved toward each other to flex or move at least a portion of the interlocking member74toward a retract or unlocking position as illustrated inFIG. 7.

A biasing member such as a spring may be provided that exerts a biasing force that may move the lever or push rod72, button68, and/or interlocking member74toward an initial or locked position. In at least one embodiment, the biasing member may exert force on and/or may be disposed on the interlocking member74. For instance, the biasing member may exert force that forces top and bottom ends or end bars of the interlocking member74away from each other.

The interlocking member74may be configured to engage one or more features such as the notches50,51and the front and back shells44,46.

The cam88is provided between the pair of elongate locking arms94,96. The elongate arms94,96extend in a lateral direction and cooperate with the slots90,92to each translate in an upright or downward direction for engaging the corresponding notches50,51in the posts48,49. The lower locking arm96is generally longer than the upper locking arm94for engaging a pair of posts48in comparison to the single post48engaged by the upper locking arm94. A pair of serpentine leaf springs98are provided on the traverse front shell56in engagement with each of the locking arms94,96for biasing the locking arms94,96into engagement with the corresponding notches50,51. The leaf springs98are in compression in the locked position ofFIG. 6and are further compressed in the locked position as illustrated inFIG. 7. The leaf springs98each include a larger lower serpentine region in comparison to the upper region to create identical force from the elongate arms94,96on each notch50,51of each post48,49. Of course, the invention contemplates any biasing member, and any leaf spring, which may be symmetrical or asymmetrical.

A tab100,102extends from each locking arm94,96and cooperates with the cam88as a follower for the cam88. Additionally, a pair of cables104,106are each mounted to the cam88. Each of the cables104,106extends about a cam surface108,110of the cam88. The cables104,106extend about an arcuate surface112,114of one of the tabs100,102. The cables104,106are each fixed to the traverse front shell56by a corresponding pin116,118.

When the push button68is actuated linearly, for example six millimeters, the rotary actuator80is rotated sixteen degrees, also an example. Rotation of the rotary actuator80results in the rotation of the cam88. The cam88acts as a pulley and rotation in the clockwise direction ofFIG. 6pulls the cables104,106about the cam surfaces108,110of the cam88thereby pulling the tabs100,102towards the cam88. The cam88includes a pair of flat surfaces120,122, which become horizontal when rotated as illustrated inFIG. 7thereby providing clearance for the pair of locking arms94,96. As the tabs100,102are translated towards the cam88, the locking arms94,96are also translated towards the cam88thereby disengaging from the notches50,51of the posts48,49thereby unlocking the positioning apparatus42.

The notches50,51are inclined or beveled to permit manual adjustment of the headrest36in the forward direction without pressing the push button68. Therefore, a forward force on the headrest36, forces the beveled surfaces of the notches50,51against the locking arms94,96, thereby disengaging the locking arms94,96, and permitting manual adjustment of the headrest36in the forward direction.

Six millimeters of translation of the push button68according to one embodiment results in sixteen degrees of rotation of the rotary actuator80and consequently four millimeters of translation of each locking arm94,96. Thus linear motion is converted to rotary motion and then to linear motion thereby equally compressing the leaf springs98symmetrically. Once the push button68is depressed, the user can translate the headrest36and consequently the headrest front shell44and the rear shell46relative to the traverse member52. Upon releasing the push button68, the leaf springs98extend thereby forcing the elongate arms94,96back into engagement with the notches50,51of the posts48,49. As the elongate arms94,96are extended, the cables104,106are extended from the cam88thereby rotating the cam88and consequently the rotary actuator80. As the rotary actuator80is rotated, the radially offset pin82engages the concave surface86of the push rod72thereby returning the push rod72and consequently the push button68to the locked position. Thus, the force of the leaf springs98may be employed for returning the push button68to the locked position. Therefore, the optional coil spring78beneath the push button68may be omitted. By utilizing rotation as the intermediate motion, counteracting forces may be minimized caused by surface friction of plastic materials.

FIGS. 8 and 9illustrate the locking arms94,96in engagement with the notches51in the posts49of the front shell46. The posts48,49of the front and rear shells44,46are aligned so that the notches50,51collectively provide a series of notches50,51.

Additionally, a plurality of bearing shafts124extend from the rear shell46through apertures through the traverse member52. A coil compression spring126is provided on each bearing shaft124connected to the rear shell46and the traverse member52. Thus, when the push button68is actuated to the unlocked position and the locking arms94,96are retracted from the notches50, the compression springs126return the headrest36to the fully rearward position illustrated inFIG. 3for resetting the position of the head restraint36. According to another embodiment, the springs126are tension springs126for extending the headrest36to the forward position ofFIG. 1, if a forward position is desired as the reset position.

The bearing shafts124help keep the front and rear shells44,46stable relative to the traverse member52. Since forces for actuating the push button68and/or translating the headrest36are typically applied to one lateral side of the head restraint assembly30, the bearing shafts prevent tilting or binding of the headrest36relative to the traverse member52. Additionally, the bearing shafts prevent kinking or buckling of the springs126. Even further, the bearing shafts124assist in alignment and assembly of the head restraint assembly30, thereby eliminating additional tooling, such as an alignment jig. The bearing shafts124may have any suitable cross-sectional geometry, such as cylindrical, a pair of intersecting rectangles or a plus (+) shape, or the like.

Referring now toFIG. 10, another head restraint assembly128is illustrated exploded in accordance with another embodiment for the head restraint assembly ofFIG. 1; and which is similar to the prior embodiment except where noted. The head restraint assembly128includes a support post130. A back shell132includes an array of posts134extending in a fore/aft direction. A series of sliders136are each provided on one of the posts134for movement in the fore/aft direction. A traverse member138is mounted to the sliders136for guiding the back shell132along the sliders136. A front shell140has a corresponding array of posts135(FIGS. 13 and 14) which are mounted to the posts134of the rear shell132. The front and rear shells132,140support a trim cover and cushion assembly142.

A positioning apparatus144includes a push button146mounted on a sleeve148through an aperture150in the front shell140. The push button146may be biased to an unlock position by a spring152. The push button146actuates a lever154which engages a pair of locking arms156,158of an interlocking member160.

The interlocking member160is illustrated enlarged inFIG. 11. The locking arms156,158include a pair of leaf springs162,164each provided proximate lateral ends thereof for uniform compression between the locking arms156,158. The interlocking member160also includes a pair of upright arms166,168spanning a region between the elongate arms156,158and extending centrally therefrom. Referring now toFIG. 12, each of the upright arms166,168includes an inclined surface170,172for engaging a corresponding inclined surface174on a concave surface174of the lever154. Additionally, a pair of posts176,178are each provided extending centrally from one of the locking arms156,158for orienting and providing bearing support to a coil spring176provided between the elongate locking arms156,158.

The interlocking member160may be formed integrally or of various components. For example, the locking arms156,158, leaf springs162,164, upright arms166,168and posts176,178may be formed integrally of a flexible polymeric material. Alternatively, the interlocking member160may be formed of various components.

As illustrated inFIG. 12, linear actuation of the push button146results in linear actuation of the lever154, which consequently results in equal linear retraction of the locking arms156,158from corresponding notches182provided in the posts134of the back shell132.

FIGS. 13 and 14illustrate the locking arms156,158in engagement with notches182in the posts134,135.FIG. 15illustrates the push button146and lever154actuated linearly inboard to the unlocked position whereby the locking arms156,158are retracted from the notches182. The concaved surface174of the lever154causes the upright arms166,168to converge thereby retracting the locking arms156,158.FIGS. 16 and 17also illustrate the unlocked positions of the locking arms156,158.

A friction feature may be provided with the rear shell134as illustrated inFIGS. 16 and 17. The friction feature may be configured to provide a desired amount of additional friction that may be overcome to permit movement of a headrest128, which includes the front shell140and trim cover and cushion assembly142, due to the movement of the traverse member148along the posts134of the back shell132. The friction feature may facilitate engagement with another notch184, which may be referred to as a soft notch. For instance, the friction feature may be provided on one of the posts134and may require a biasing force to overcome the compression provided by the springs162,164,180. The friction feature may be contoured to receive the lower locking arm158. The notch184may be contoured to permit advancement of the head restraint36by utilizing inclined or beveled surfaces between the notch184. The notch184may be biased or raked in one direction so that the headrest128can be adjusted in one direction, such as a forward direction, without pressing the push button146.

FIGS. 18-20illustrate a head restraint assembly186according to yet another embodiment. As illustrated inFIGS. 18 and 19, linear actuation of a push rod188relative to a traverse member190results in linear actuation of an output end192of the push rod188. The output end192is inclined and engages a corresponding intermediate slide194. The intermediate slide194cooperates with the traverse member190for linear travel in a fore and aft direction. Thus, linear actuation of the push rod188in an inboard lateral direction causes the intermediate slide194to travel in the fore direction.

Referring toFIG. 20, the intermediate slide194includes a pair of inclined surfaces196,198that are each aligned with an interlocking member200so that when the intermediate slide194is actuated in the fore direction, the interlocking member200is retracted from the traverse member190. The traverse member190is mounted to a support post202, and a rear shell204is supported for translation on the traverse member190. The traverse member190includes a series of sliders206, which each receive a post208extending from a front shell210of the head restraint assembly180to the rear shell204. A series of notches212are provided in each of the posts208such that retraction of the interlocking member200permits translation of the front and rear shells204,210relative to the support posts202.

For the head restraint assembly186ofFIGS. 18-20, linear actuation of a push button (not shown) results in linear actuation of the push rod188, consequently linear actuation of the intermediate slide194and linear actuation of the interlocking member200. When a force is removed from the push button, springs214of the interlocking member200extend locking arms216,218back into engagement with the notches212. The translation of the locking arms216,218forces the intermediate slide194in an aft direction which thereby extends the push rod188in a laterally outboard direction.

FIG. 21illustrates another movable head restraint assembly220with a traverse member222on a support post224. The traverse member222includes a series of guides226for receiving a plurality of posts of the associated headrest, which is removed from this figure, and which is similar to the prior embodiments. A pair of locking arms228,230are mounted for translation on the traverse member222for engaging notches within the posts. A single leaf spring232is depicted in engagement with both locking arms228,230.

A push button (not shown) is mounted in a sleeve234on the headrest. The push button actuates a push rod236. The push rod has a contoured end238that engages the leaf spring232. The contoured end238is shaped to be homogenous with a contour of the leaf spring232to avoid crippling of the leaf spring232. Translation of the push rod236inboard retracts the leaf spring232toward the push rod236, thereby retracting the locking arms228,230from the notches for permitting fore/aft adjustment of the associated headrest. Release of the push button causes the leaf spring232to extend to the position depicted thereby returning the locking arms228,230into engagement with the notches. Return of the leaf spring also translates the push rod236to an outboard position, which in turn, returns the push button to the locked position.

In at least one or more embodiments, the head restraint may provide a reduced number of parts, faster assembly, smaller package space, and help meet regulatory requirements.