Head support assembly and head support unit

Abstract

According to an aspect of the presently disclosed subject matter, there is provided a head support assembly attachable to a seat having right and left frame members. The head support assembly includes right and left support columns, right and left couplers articulatable to the right and left frame members, respectively, and configured to independently restrain the right and left support columns, respectively, to facilitate at least partial tilt of the columns about a pitch axis extending between the right and left couplers, and a head support unit articulatable to an upper right portion of the right support column and an upper left portion of the left support column. The head support assembly of the first aspect is configured to be attached to any seat having right and left frame members, and the head support unit is configured to be worn by a user seated in the seat to provide support to the head and prevent the head from tilting forward and / or downward. In some cases, the head support unit can have a support configured with a forward portion to which a head restraint can be attached. In such cases, the head restraint is configured to provide improved head and neck support to the user while seated in the seat.

Description

[Technical Field]

[0001] SUMMARY The present disclosure relates to a head support assembly for a seat and a head support unit for use with the head support assembly. [Background technology]

[0002] U.S. Patent No. 9,566,885 discloses a head restraint including a headrest member having a back portion and two side portions extending therefrom, the side portions being foldable relative to the back portion so as to enable the headrest member to assume a first state in which the side portions are spaced apart from each other by a first range and a second state in which the side portions are spaced apart from each other by a second range smaller than the first range; an attachment device articulated to the headrest member for attaching the head restraint to a seat; and a restraining member pivotally articulated to the side portions and configured to rotate between at least an upper position and a lower position, wherein displacement of the restraining member between the upper position and the lower position is configured to place the headrest member in the first state and the second state, respectively.

[0003] WO 2019 / 207580, the contents of which are incorporated by reference, discloses a head support unit for a head support assembly having right and left support columns, the head support unit comprising a support, right and left mounting elements configured to articulate with the right and left support columns, respectively, and an adjustment mechanism configured to selectively adjust the positions of the right and left mounting elements relative to one another from at least an extended position toward a retracted position.

[0004] However, in order to use the head support assembly and head support unit of WO 2019 / 207580 when a seated user has dropped neck syndrome or any other condition that causes the head to tilt downward, the user's head must first be manually supported while applying significant force, and only once the head is correctly positioned can the head support unit be attached thereto. This method of operating the head support assembly and head support unit of WO 2019 / 207580 may require two or more operators who must apply a lot of force, which can cause significant discomfort or even pain to the seated user. Summary of the Invention

[0005] According to a first aspect of the presently disclosed subject matter, there is provided a head support assembly attachable to a seat comprising a right frame member and a left frame member, the head support assembly comprising: a right support column and a left support column; a right coupler and a left coupler articulatable to the right frame member and the left frame member, respectively, and configured to independently restrain the right and left struts, respectively, to facilitate at least partial tilt of the struts about a pitch axis extending between the right coupler and the left coupler; a head support unit articulatable to the upper right portion of the right column and the upper left portion of the left column; A head support assembly is provided comprising:

[0006] As used herein, the term "seat" means any device having a seat and back configured to support a seated user, and may be any one of a wheelchair, booster seat, safety seat, stroller, vehicle seat, chair, bench, etc.

[0007] The head support assembly of the first aspect is configured to be attached to any seat having a right frame member and a left frame member, and the head support unit is configured to be worn over the head of a user seated in the seat to provide support to the head and prevent the head from tilting forward and / or downward. In some cases, the head support unit can have a support configured with a front portion to which a head restraint can be attached. In such cases, the head restraint is configured to provide improved head and neck support to the user while seated in the seat, for example, if the user falls asleep or in the case of an individual with a physical disability. More specifically, the head restraint is configured to prevent the user's head from falling forward and further to prevent the user's head from tilting to the left or right side. This provides comfortable and stable support for the user's head while seated in the seat. According to a specific example, the head restraint can be that disclosed in U.S. Patent No. 9,566,885, the contents of which are incorporated herein by reference. In use, when a user's head is attached to the head restraint, the restraining member of the head restraint can be positioned in its lower position in front of the user's forehead.

[0008] The head support assembly of the first aspect is also configured to be used to hold the head upright when a seated user has dropped neck syndrome or any other condition affecting the neck muscles, such as ALS, CP, Parkinson's disease, muscular dystrophy, kyphosis, scoliosis, as well as conditions resulting from brain trauma, radiation therapy, and advanced degenerative spinal conditions. Use of the head support assembly can provide the user with comfort, pain relief, the ability to perform daily activities, and the ability to breathe and swallow properly.

[0009] In such cases, instead of manually lifting and strengthening the user's head before attaching it to the head support unit (which may even be impossible in some cases), the head support unit of the head support assembly is configured to tilt toward the user's head by tilting the right and / or left support columns. This allows the head to be attached to the head support unit and / or its attached head restraint when the head support unit is brought close to the user's head, and the entire head support unit can be tilted in the opposite direction along with the user's head, thereby strengthening the user's neck and back and lifting the head. In this case, the bottoms of the right and left support columns can be used as levers to tilt the head in the opposite direction and strengthen the user's back.

[0010] Any one or more of the following features, designs, and configurations may be incorporated, independently or in combination, into the head support unit and head support assembly of the first aspect of the subject matter of this disclosure.

[0011] The right and left couplers may be articulatable to the right and left frame members, respectively, and may be configured to independently constrain the right and left struts, respectively, to also facilitate selective sliding displacement of the struts along their longitudinal axes, which may also assist in bringing the head support unit as close as possible to the user's head before lifting the head support unit, providing an additional degree of freedom.

[0012] The right and left couplers may each include a mounting member articulatable to the respective right and left frame members, and a strut receiving member configured to restrain the respective right and left strut and pivotable relative to the mounting member to facilitate tilting of the strut about the pitch axis.

[0013] The mounting members may be articulatable to the respective right and left frame members to facilitate rotational displacement of the respective struts about the roll axis of the respective frame members.

[0014] The mounting members may comprise a holding portion configured to articulate by holding the respective right and left frame members, and the holding portion may comprise a tensioning mechanism configured to control tension applied by the holding portion to the respective right and left frame members to control the ability of the respective struts to rotate relative to the respective right and left frame members.

[0015] In some embodiments, the embracing portion is in the form of a bridge and is shaped and sized to fit over the frame member together with a portion of the coupler. One side of the bridge may be pivotally coupled to the coupler to allow switching between an embracing state in which the bridge interfaces with the coupler on its two sides and an open state in which the bridge is in a pivoted position to allow removal or insertion of the frame member into the embracing area defined between the frame member and the embracing portion.

[0016] The cradling portion may be configured to receive a size adaptor element to reduce the size of the cradling area to allow adaptive fitting to frame members of different sizes.

[0017] Pivoting of the strut receiving member relative to the mounting member and rotational displacement of the mounting member relative to the respective right and left frame members may be configured to occur simultaneously to facilitate displacement of the respective struts about both the pitch and roll axes.

[0018] At least one of the right coupler and the left coupler may include a primary angle locking mechanism configured to selectively constrain the angular position of the mounting member relative to the support post receiving member when tilted, thereby fixing the tilt angle between the respective support post and a backrest plane defined by the seat back.

[0019] The post receiving member may include a height locking mechanism configured to selectively restrain each post at different positions relative to the post receiving member along the longitudinal axis.

[0020] The main angle and height locking mechanisms may be located on either side of each coupler.

[0021] The head support unit may include a right mounting element articulatable at an upper right portion, a left mounting element articulatable at an upper left portion, and a support disposed between the right and left mounting elements, and the support may be twistable relative to at least one of the right and left mounting elements.

[0022] The right and left mounting elements can be disposed on opposite sides of the support via right and left extension elements, respectively, and at least one of the right and left mounting elements can be pivotally connected to its respective extension element to facilitate twisting of the support relative to a respective one of the right and left mounting elements.

[0023] The right and left mounting elements may be pivotally connected to the right and left extension elements, respectively, to allow independent pivotal displacement thereof.

[0024] In some embodiments, each of the attachment elements is rotatable about a horizontal axis perpendicular to the longitudinal axis of the support. This rotation is possible because each attachment is pivotally coupled to its respective upper portion. More specifically, each of the attachment elements is pivoted on an axis extending from its respective extension element through its respective attachment element to the support. In other words, the attachment elements are sandwiched between their respective supports and extension elements, and a common axis is fixed to each of the supports and extension elements while passing through each of the attachment elements, allowing their rotation about the axis defined by that axis. Each attachment element can rotate independently of the other. In some embodiments, rotation of the attachment elements is permitted up to 180°.

[0025] The head support assembly may further comprise at least one auxiliary angle locking mechanism configured to selectively lock the torsional angle between the support and the respective right and left struts during twisting.

[0026] The head support unit may include an adjustment mechanism configured to selectively adjust the positions of the right and left mounting elements relative to one another by displacing the right and left extension elements between retracted and extended positions, respectively, and a counterbalancing mechanism operative with the adjustment mechanism to selectively allow free displacement of the support relative to at least one of the right and left extension elements. The counterbalancing mechanism thus allows counteracting the adjustment mechanism for displacing the support to the right or left, which provides an additional degree of freedom for properly positioning the support of the head support unit relative to the head of a seated user.

[0027] The neutralization mechanism may be switchable between an operative state in which the adjustment mechanism operates to displace both the right and left extension elements, and a completely inoperative state in which the support is freely displaceable relative to both the right and left extension elements and independent of the adjustment mechanism.

[0028] When the right and left mounting elements are articulated with the right and left support columns, in a completely inoperative state of the neutralization mechanism, the support body may be freely displaceable towards one of the right and left extension elements and away from the other of the right and left extension elements.

[0029] The adjustment mechanism may include right and left drive elements disposed opposite each other along the lengths of the right and left extension elements, respectively, and a drive gear including drive portions configured to engage the right and left drive elements in the operative state of the neutralization mechanism and to displace the right and left extension elements, respectively, upon rotation of the drive gear.

[0030] Rotation of the drive gear in a first direction can involve adjustment of each of the right and left attachment elements toward an extended position, and rotation in a second, opposite direction can involve adjustment of each of the right and left attachment elements toward a retracted position. The neutralizing mechanism can include a neutralizing member configured to axially displace the drive portion along its rotation axis between an engaged position corresponding to an operative state in which the drive portion is engaged with the right and left drive elements, and a disengaged position corresponding to an inoperative state in which the drive portion is disengaged from both the right and left extension elements.

[0031] The neutralizing member may include a drive portion, and displacement of the drive portion may be effected by axial displacement of the neutralizing member.

[0032] The drive portion may be a pinion, and each of the left and right drive elements may be a rack.

[0033] The neutralizing member may be coaxially disposed within the drive gear.

[0034] The adjustment mechanism may be configured to adjust the position of both the right and left mounting elements simultaneously.

[0035] The simultaneous adjustment of the positions of the right and left mounting elements may be such that the right and left mounting elements are displaced along the same distance away from each other.

[0036] The head support unit further includes a unit locking mechanism that operates in conjunction with the adjustment mechanism to selectively lock the positions of the right and left extension elements and prevent displacement of the right and left extension elements relative to the support.

[0037] The unit locking mechanism may be configured to lock the right and left mounting elements at any one of a plurality of intermediate positions between the extended position and the retracted position.

[0038] The drive gear may further include a latch portion selectively engageable with a lock portion of the support, the latch portion and lock portion constituting at least a part of the unit securing mechanism. The drive gear may be configurable between a locked state in which the latch portion engages the lock portion to prevent rotation of the drive gear, and an unlocked state in which the latch portion disengages from the lock portion to allow rotation of the drive gear and adjustment of the positions of the right and left mounting elements relative to each other, respectively.

[0039] The support may have a longitudinal axis, and the positions of the right and left mounting elements relative to each other may be linearly adjustable along the longitudinal axis.

[0040] The adjustment mechanism and the neutralization mechanism may extend at least partially within the support.

[0041] In summary, the head support assembly of the first aspect may have five independent displacement mechanisms, allowing the spatial position and orientation of the head support unit and its support to be changed in five different independent degrees of freedom: the first displacement mechanism is provided by pivotal rotation of the support receiving member relative to the mounting member, allowing tilting of the support about the pitch axis; the second displacement mechanism is provided by rotational displacement of the mounting members relative to each of the right and left frame members, allowing the struts to tilt about their respective roll axes; ● The third displacement mechanism provided by the height locking mechanism allows for sliding displacement of the struts along their respective longitudinal axes, and in some embodiments the struts are telescopic, making the assembly more compact and efficient for storage and transport. Thus, the struts can be folded to a minimum size where the maximum portion of the strut's length is stored within the telescopic portion, and can be extended to a maximum size where all portions of the strut extend outside the telescopic portion. the fourth displacement mechanism provided by the neutralization mechanism allows the support to be displaced along its longitudinal axis without displacing the right and left struts and their respective right and left extension elements; - The fifth displacement mechanism is provided by a right auxiliary angle fixing mechanism and a left auxiliary angle fixing mechanism, which allows the support to be twisted independently relative to the right and left mounting elements.

[0042] According to a second aspect of the subject matter of the present disclosure, there is provided a head support unit for a head support assembly having right and left support columns attachable to right and left frame members, respectively, of a seat, the support unit comprising: A support; right and left mounting elements configured to articulate with the right and left support columns, respectively, the right and left mounting elements being disposed on opposite sides of the support and connected to the support via right and left extension elements, respectively; an adjustment mechanism configured to selectively adjust the positions of the right and left attachment elements relative to one another by displacing the right and left extension elements, respectively, between a retracted position and an extended position; A head support unit is provided that includes a counterbalance mechanism that operates in conjunction with the adjustment mechanism to selectively allow free displacement of the support relative to at least one of the right extension element and the left extension element.

[0043] The right and left support columns typically extend vertically upward and parallel to each other, defining a distance between them. When the right and left support columns are attached to the right and left frame members, the distance between them is determined by the width of the seat, particularly the seat's configuration and the distance between the right and left frame members. This distance may vary from seat to seat or may depend on the location at which the left and right support columns are articulated to the side frames of a particular seat. Thus, the right and left mounting elements are adjustable relative to each other via an adjustment mechanism to removably attach the head support unit to the right and left support columns. The right and left mounting elements are also adjustable so that the distance between them matches the distance between the right and left support columns attached to the right and left frame members. This adjustment can enable the right and left mounting elements to assume any one of a plurality of intermediate positions or any one of a plurality of discrete predetermined positions between the extended and retracted positions.

[0044] When articulated to the upper end of the support column, the support unit may be configured to provide support to the head of a user seated in the seat, as described above with respect to the first aspect of the subject matter of the present disclosure.

[0045] The second embodiment of the counterbalance mechanism is configured for use when a user's head is tilted downward to the right or left and the support needs to be aligned with and positioned behind the tilted head. The counterbalance mechanism thus provides the freedom to move the support to the right or left to position the support as close as possible to the user's head, minimizing the need for an operator to manually lift and center the user's head when attaching it to the support.

[0046] Any one or more of the following features, designs, and configurations may be incorporated, independently or in combination, into the head support unit of the second aspect of the subject matter of the present disclosure.

[0047] The neutralization mechanism may be switchable between an operative state in which the adjustment mechanism operates to displace both the right and left extension elements, and a completely inoperative state in which the support is freely displaceable relative to both the right and left extension elements and independent of the adjustment mechanism.

[0048] When the right and left mounting elements are articulated with the right and left support columns, in a completely inoperative state of the neutralization mechanism, the support body may be freely displaceable towards one of the right and left extension elements and away from the other of the right and left extension elements.

[0049] The adjustment mechanism may include right and left drive elements disposed opposite each other along the lengths of the right and left extension elements, respectively, and a drive gear including drive portions configured to engage the right and left drive elements in the operative state of the neutralization mechanism and to displace the right and left extension elements, respectively, upon rotation of the drive gear.

[0050] Rotation of the drive gear in a first direction can involve adjustment of each of the right and left mounting elements toward an extended position, and rotation in a second, opposite direction can involve adjustment of each of the right and left mounting elements toward a retracted position.

[0051] The neutralizing mechanism may comprise a neutralizing member configured to axially displace the drive portion along its axis of rotation between an engaged position corresponding to an operative state in which the drive portion is engaged with the right and left drive elements, and a disengaged position corresponding to a non-operative state in which the drive portion is disengaged from both the right and left extension elements.

[0052] The neutralizing member may include a drive portion, and displacement of the drive portion may be effected by axial displacement of the neutralizing member.

[0053] The drive portion may be a pinion, and each of the left and right drive elements may be a rack.

[0054] The neutralizing member may be coaxially disposed within the drive gear.

[0055] The adjustment mechanism may be configured to adjust the position of both the right and left mounting elements simultaneously.

[0056] The simultaneous adjustment of the positions of the right and left mounting elements may be such that the right and left mounting elements are displaced along the same distance away from each other.

[0057] The head support unit may further comprise a unit fixing mechanism that operates in conjunction with the adjustment mechanism to selectively fix the positions of the right and left extension elements and prevent displacement of the right and left extension elements relative to the support.

[0058] The unit locking mechanism may be configured to lock the right and left mounting elements at any one of a plurality of intermediate positions between the extended position and the retracted position.

[0059] The drive gear may further include a latch portion selectively engageable with a lock portion of the support, the latch portion and lock portion constituting at least a part of the unit securing mechanism. The drive gear may be configurable between a locked state in which the latch portion engages the lock portion to prevent rotation of the drive gear, and an unlocked state in which the latch portion disengages from the lock portion to allow rotation of the drive gear and adjustment of the positions of the right and left mounting elements relative to each other, respectively.

[0060] The support may have a longitudinal axis, and the positions of the right and left mounting elements relative to each other may be linearly adjustable along the longitudinal axis.

[0061] The adjustment mechanism and the neutralization mechanism may extend at least partially within the support.

[0062] At least one of the right and left mounting elements may be pivotally connected to its respective extension element to facilitate twisting of the support relative to the respective one of the right and left mounting elements.

[0063] The head support unit may further comprise at least one auxiliary angle locking mechanism configured to selectively lock the torsion angle between the support and the respective right and left support columns during said torsion.

[0064] The head support unit may be configured to receive a headrest member including a central portion and two side portions that are foldable relative to the central portion to allow the headrest member to assume a first state in which the side portions are spaced apart from one another by a first range and a second state in which the side portions are spaced apart from one another by a second range that is smaller than the first range.

[0065] The headrest member may be removably attached to the head support unit, for example, by fitting attachment tabs into insertable slits formed in the head support unit, or by Velcro® attachment to the head support unit.

[0066] In some embodiments, the headrest member further comprises a restraint member attached to the side and configured to rotate between at least an upper position and a lower position, and when in the lower position, the restraint member is configured to support the subject's forehead on the subject's head supported by the head support unit.

[0067] In some embodiments, displacement of the restraining member between its upper position and its lower position is configured to cause the headrest member to assume its first and second states, respectively.

[0068] In some embodiments, the head support units include corresponding head support unit sides that are rotatable about axes parallel to the longitudinal axis. The head support unit sides are typically rigid, and the sides of the head rest member are attached to or configured to fit onto the head support unit sides such that the head rest member sides and the head support unit sides fold together. That is, the sides of the head rest member are associated with or fit onto the sides of the head support unit, such that any movement of one of them results in movement of the other.

[0069] The head support unit includes a locking mechanism for selectively allowing (i) each of the head support unit sides to be locked independently in a desired folded position, regardless of rotational movement of the restraining member or any other element. Note that each side can be adjusted to a different folded position, or (ii) free movement of the side. Thus, for example, the sides can move freely, resulting in the sides folding to different degrees with rotational movement of the restraining member.

[0070] In some embodiments, a locking mechanism may be embedded in the headrest member to (i) independently lock each of the sides of the headrest member in a desired folded position, or (ii) selectively allow free movement of that side.

[0071] It should be noted that in some embodiments, each side of either the headrest member or head support unit may have its own locking mechanism that independently and selectively controls the path of movement of its respective side, i.e., locking it in a particular folded position or allowing its free folding movement.

[0072] In some embodiments, the central portion comprises a central cushion and each side portion comprises a respective side cushion foldable therewith, the side cushions being separated from the central cushion to allow folding of the sides, i.e., the gap between the central and side cushions generally serves as an axis or folding portion about which folding of the sides occurs.

[0073] The central cushion protrudes from a central plane defined by the central portion, and the side cushions protrude from sides defined by the side portions, the side cushions protruding more than the central cushion.

[0074] In some embodiments, the central cushion includes a first upper portion that protrudes from the central surface to a first extent and a second lower portion that protrudes from the central surface to a second extent, the second extent being greater than the first extent. The central cushion has a contour that conforms to the contours of the occipital bone. Thus, the lower portion of the cushion is thicker than the upper portion of the cushion.

[0075] In some embodiments, the central portion comprises a pair of support cushions, each member of the pair disposed on a different side of and spaced apart from the central cushion, the support cushions being disposed on two sides of the lower portion of the central cushion to provide additional peripheral support to the subject's occipital bone.

[0076] In some embodiments, each cushion of the pair projects from the central plane to a third extent that is greater than the second extent.

[0077] It should be noted that the cushion of the headrest member in any of the above-described embodiments may be removably attached to a respective portion of the headrest member, i.e., one of the central or side portions. This may be done, for example, by a Velcro® attachment. Thus, a personalized cushioning system may be created for each individual who may use the headrest member, with the headrest member configured to receive the personalized cushioning system of the individual using it.

[0078] In some embodiments, the head support assembly further comprises a chin support unit removably coupled to the headrest member, for example, by Velcro.

[0079] Another aspect of the present disclosure provides a head support unit connectable to the head support assembly of any one of the above-described embodiments. The head support unit includes a head support unit central portion for supporting the subject's head and a coupling arrangement, e.g., by threads at several screw locations, for enabling coupling to the head support assembly. The head support unit includes two head support unit side portions, each independently foldable about a longitudinal axis along a range of folding positions relative to the central portion between a closed folded position and an open folded position.

[0080] It should be noted that in some embodiments, the head support unit can be adjusted to two states: (i) independently locking each head support unit side in a desired folded position, or (ii) free movement of the sides.

[0081] In some embodiments of the head support unit, each side of the head support unit includes its own respective locking mechanism. Yet another aspect of the present disclosure provides a headrest member receivable within the head support unit of a head support assembly. The head support unit is part of the head support assembly configured to couple to a wheelchair. The head support unit is made of a rigid material, and the headrest member is made of a soft material that allows portions of the headrest member to be folded during use. The headrest member includes a center portion and two side portions that are foldable relative to the center portion to allow the headrest member to assume a first state in which the side portions are spaced apart from each other by a first range and a second state in which the side portions are spaced apart from each other by a second range that is smaller than the first range. The headrest member is removably attached to the head support unit, for example, by fitting attachment tabs into insertable slits formed in the head support unit or by Velcro® attachment to the head support unit. The head support units include corresponding head support unit sides, which are typically rigid. The sides of the head rest member fit onto the head support unit sides so that the head support unit sides and the head rest member sides fold together. The head support unit sides are rotatable about parallel longitudinal axes, and the sides of the head rest member are associated with or fit onto the sides of the head support unit, such that any movement of one of them results in movement of the other.

[0082] In some embodiments, the headrest member further comprises a restraint member attached to the side and configured to rotate between at least an upper position and a lower position, and when in the lower position, the restraint member is configured to support the subject's forehead on the subject's head supported by the head support unit.

[0083] In some embodiments, displacement of the restraining member between its upper position and its lower position is configured to cause the headrest member to assume its first and second states, respectively.

[0084] In some embodiments, the headrest member further includes (i) a locking mechanism that selectively allows each of the sides of the headrest member to be locked independently in a desired folded position, regardless of rotational movement of the restraining member or any other element. Note that each side may be adjusted to a different folded position independently of the other, or (ii) free movement of the side.

[0085] In some embodiments, each side of the headrest member includes its own respective locking mechanism.

[0086] In some embodiments, the central portion comprises a central cushion and each side portion comprises a respective side cushion foldable therewith, the side cushions being separated from the central cushion to allow folding of the sides, i.e., the gap between the central cushion and the side cushions generally serves as an axis about which the side portions fold.

[0087] The central cushion protrudes from a central plane defined by the central portion, and the side cushions protrude from sides defined by the side portions, the side cushions protruding more than the central cushion.

[0088] In some embodiments, the central cushion includes a first upper portion that protrudes from the central surface to a first extent and a second lower portion that protrudes from the central surface to a second extent, the second extent being greater than the first extent. The central cushion has a contour that conforms to the contours of the occipital bone. Thus, the lower portion of the cushion is thicker than the upper portion of the cushion.

[0089] In some embodiments, the central portion comprises a pair of support cushions, each member of the pair disposed on a different side of and spaced apart from the central cushion, the support cushions being disposed on two sides of the lower portion of the central cushion to provide additional peripheral support to the subject's occipital bone.

[0090] In some embodiments, each cushion of the pair projects from the central plane to a third extent that is greater than the second extent.

[0091] In some embodiments, the headrest member further comprises a chin support unit removably coupled to the headrest member, for example by Velcro.

[0092] Embodiment Below are various non-limiting embodiments of different aspects of the present disclosure.

[0093] 1. A head support assembly attachable to a seat having a right frame member and a left frame member, the head support assembly comprising: a right support column and a left support column; a right coupler and a left coupler articulatable to the right frame member and the left frame member, respectively, and configured to independently restrain the right and left struts, respectively, to facilitate at least partial tilt of the struts about a pitch axis extending between the right coupler and the left coupler; a head support unit articulatable to the upper right portion of the right column and the upper left portion of the left column; A head support assembly is provided comprising:

[0094] 2. The head support assembly of embodiment 1, wherein the right and left couplers are articulatable to the right and left frame members, respectively, and are configured to independently constrain the right and left support columns, respectively, so as to also facilitate selective sliding displacement of the columns along their longitudinal axes.

[0095] 3. The head support assembly of embodiment 1 or 2, wherein the right and left couplers each may include a mounting member articulatable to the respective right and left frame members, and a support receiving member configured to restrain the respective right and left support pillars and pivotable relative to the mounting member to facilitate tilting of the pillars about the pitch axis.

[0096] 4. A head support assembly as described in embodiment 3, wherein the mounting members are articulatable to the respective right and left frame members to facilitate rotational displacement of the respective struts about the roll axis of the respective frame members.

[0097] 5. A head support assembly as described in embodiment 4, wherein the mounting member comprises a holding portion configured to articulate by holding the respective right and left frame members, and the holding portion comprises a tensioning mechanism configured to control the tension applied by the holding portion to the respective right and left frame members to control the ability of the respective support columns to rotate relative to the respective right and left frame members.

[0098] 6. A head support assembly as described in claim 4 or 5, when dependent on claim 2, wherein pivoting of the support column receiving member relative to the mounting member and rotational displacement of the mounting member relative to the respective right and left frame members are configured to occur simultaneously to facilitate displacement of the respective support columns about both the pitch axis and the roll axis.

[0099] 7. A head support assembly as described in any one of embodiments 3 to 6, wherein at least one of the right coupler and the left coupler includes a primary angle locking mechanism configured to selectively constrain the angular position of the mounting member relative to the support post receiving member when tilted, thereby fixing the tilt angle between the respective support post and a backrest plane defined by the seat back.

[0100] 8. A head support assembly according to any one of embodiments 3 to 7, wherein the support column receiving member comprises a height locking mechanism configured to selectively restrain each support column at different positions relative to the support column receiving member along the longitudinal axis.

[0101] 9. When dependent on embodiment 7, a head support assembly as described in embodiment 8, wherein the main angle fixing mechanism and height fixing mechanism are arranged on both sides of each coupler.

[0102] 10. A head support assembly as described in any one of embodiments 1 to 9, wherein the head support unit comprises a right mounting element articulatable at the upper right portion, a left mounting element articulatable at the upper left portion, and a support disposed between the right mounting element and the left mounting element, wherein the support is twistable relative to at least one of the right mounting element and the left mounting element.

[0103] 11. A head support assembly as described in embodiment 10, wherein the right and left mounting elements are arranged on either side of the support via right and left extension elements, respectively, and at least one of the right and left mounting elements is pivotally connected to its respective extension element to facilitate twisting of the support relative to the respective one of the right and left mounting elements.

[0104] 12. A head support assembly as described in embodiment 11, wherein the right and left mounting elements are pivotally connected to the right and left extension elements, respectively, to allow independent pivotal displacement thereof.

[0105] 13. A head support assembly according to any one of embodiments 10 to 12, further comprising at least one auxiliary angle locking mechanism configured to selectively lock the torsional angle between the support and the respective right and left support columns during twisting.

[0106] 14. A head support assembly according to any one of embodiments 10 to 13 when belonging to claim 11, wherein the head support unit comprises an adjustment mechanism configured to selectively adjust the positions of the right and left attachment elements relative to each other by displacing the right and left extension elements between a retracted position and an extended position, respectively, and a neutralization mechanism operating together with the adjustment mechanism to selectively allow free displacement of the support relative to at least one of the right and left extension elements.

[0107] 15. A head support assembly as described in embodiment 14, wherein the neutralization mechanism is switchable between an operating state in which the adjustment mechanism operates to displace both the right extension element and the left extension element, and a completely inoperative state in which the support is freely displaceable relative to both the right extension element and the left extension element and regardless of the adjustment mechanism.

[0108] 16. A head support assembly as described in embodiment 15, wherein when the right and left mounting elements are articulated with the right and left support columns, in a completely inoperative state of the neutralization mechanism, the support body is freely displaceable toward one of the right and left extension elements and away from the other of the right and left extension elements.

[0109] 17. A head support assembly as described in embodiment 15 or 16, wherein the adjustment mechanism includes a right drive element and a left drive element arranged opposite each other along the lengths of the right extension element and the left extension element, respectively, and a drive gear including a drive portion configured to engage with the right drive element and the left drive element in the operating state of the neutralization mechanism and to displace the right extension element and the left extension element, respectively, upon rotation of the drive gear.

[0110] 18. A head support assembly as described in embodiment 17, wherein rotation of the drive gear in a first direction involves adjustment of each of the right and left mounting elements toward an extended position, and rotation in a second, opposite direction involves adjustment of each of the right and left mounting elements toward a retracted position.

[0111] 19. A head support assembly according to claim 17 or 18, wherein the neutralizing mechanism comprises a neutralizing member configured to axially displace the drive portion along its axis of rotation between an engaged position corresponding to an operative state, in which the drive portion is engaged with the right drive element and the left drive element, and a disengaged position corresponding to an inoperative state, in which the drive portion is disengaged from both the right extension element and the left extension element.

[0112] 20. A head support assembly as described in embodiment 19, wherein the neutralizing member includes the drive portion, and the displacement of the drive portion is configured to be effected by axial displacement of the neutralizing member.

[0113] 21. A head support assembly according to any one of embodiments 17 to 20, wherein the drive portion is a pinion and each of the right and left drive elements is a rack.

[0114] 22. A head support assembly as described in embodiment 19, wherein the neutralizing member is coaxially disposed within the drive gear.

[0115] 23. A head support assembly according to any one of embodiments 15 to 22, wherein the adjustment mechanism is configured to simultaneously adjust the position of both the right and left mounting elements.

[0116] 24. A head support assembly as described in embodiment 23, wherein the simultaneous adjustment of the positions of the right and left mounting elements is such that the right and left mounting elements are displaced along the same distance away from each other.

[0117] 25. A head support assembly as described in any one of embodiments 15 to 24, wherein the head support unit further comprises a unit fixing mechanism that operates in conjunction with the adjustment mechanism to selectively fix the positions of the right extension element and the left extension element and prevent displacement of the right extension element and the left extension element relative to the support.

[0118] 26. A head support assembly as described in embodiment 25, wherein the unit locking mechanism is configured to lock the right mounting element and the left mounting element at any one of a plurality of intermediate positions between the extended position and the retracted position.

[0119] 27. A head support assembly as described in embodiment 25 or 26, wherein the drive gear further comprises a latch portion selectively engageable with a lock portion of the support, the latch portion and the lock portion constituting at least a part of a unit fixing mechanism, and the drive gear is configurable between a locked state in which the latch portion engages with the lock portion to prevent rotation of the drive gear, and an unlocked state in which the latch portion disengages from the lock portion to allow rotation of the drive gear and adjustment of the positions of the right and left mounting elements relative to each other, respectively.

[0120] 28. A head support assembly as described in any one of embodiments 15 to 27, wherein the support has a longitudinal axis and the positions of the right and left mounting elements relative to each other are linearly adjustable along the longitudinal axis.

[0121] 29. A head support assembly according to any one of embodiments 15 to 28, wherein the adjustment mechanism and the neutralization mechanism extend at least partially within the support.

[0122] 30. A head support assembly as described in any one of embodiments 1 to 29, wherein the head support unit is configured to receive a headrest member having a central portion and two side portions, the two side portions being foldable relative to the central portion to enable the headrest member to assume a first state in which the side portions are spaced apart from each other by a first range and a second state in which the side portions are spaced apart from each other by a second range smaller than the first range.

[0123] 31. The head support assembly of embodiment 30, wherein the headrest member is removably attachable to the head support unit.

[0124] 32. A head support assembly as described in embodiment 30 or 31, wherein the headrest member further comprises a restraint member attached to the side and configured to rotate between at least an upper position and a lower position, and when in the lower position, the restraint member is configured to support the subject's forehead on the subject's head supported by the head support unit.

[0125] 33. The head support assembly of embodiment 32, wherein displacement of the restraint member between its upper position and its lower position is configured to cause the headrest member to assume its first and second states, respectively.

[0126] 34. The head support assembly of any one of embodiments 30 to 33, wherein the head support unit includes corresponding head support unit sides, and the sides of the head rest member are configured to be attached to or fit into the head support unit sides such that the sides of the head rest member and the head support unit sides fold together.

[0127] 35. A head support assembly as described in embodiment 34, wherein the head support unit includes a locking mechanism for (i) independently locking each of the head support unit sides in a desired folded position, or (ii) allowing free movement of the sides.

[0128] 36. The head support assembly of embodiment 34 or 35, wherein each side of the head support unit includes a respective locking mechanism.

[0129] 37. The head support assembly of any one of embodiments 30 to 36, wherein the central portion includes a central cushion and each side portion includes a respective side cushion.

[0130] 38. A head support assembly as described in embodiment 37, wherein the central cushion protrudes from a central plane defined by the central portion, and the side cushions protrude from sides defined by the side portions, the side cushions protruding more than the central cushion.

[0131] 39. A head support assembly as described in embodiment 37 or 38, wherein the central cushion has a first portion protruding from the central surface to a first range and a second portion protruding from the central surface to a second range, the second range being greater than the first range.

[0132] 40. A head support assembly as claimed in any one of claims 37 to 39, wherein the central portion comprises a pair of support cushions, each member of the pair being located on a different side of the central cushion and spaced apart therefrom.

[0133] 41. The head support assembly of embodiment 40, wherein each cushion of the pair protrudes from the central plane to a third range that is greater than the second range.

[0134] 42. The head support assembly of embodiment 41, comprising a chin support unit removably coupled to the headrest member.

[0135] 43. A head support unit for a head support assembly having right and left support posts attachable to right and left frame members, respectively, of a seat, the support unit comprising: A support; right and left mounting elements configured to articulate with the right and left support columns, respectively, the right and left mounting elements being disposed on opposite sides of the support and connected to the support via right and left extension elements, respectively; an adjustment mechanism configured to selectively adjust the positions of the right and left attachment elements relative to one another by displacing the right and left extension elements, respectively, between a retracted position and an extended position; a neutralization mechanism that operates in conjunction with the adjustment mechanism to selectively allow free displacement of the support relative to at least one of the right extension element and the left extension element.

[0136] 44. A head support unit as described in embodiment 43, wherein the neutralization mechanism is switchable between an operating state in which the adjustment mechanism operates to displace both the right extension element and the left extension element, and a completely inoperative state in which the support is freely displaceable relative to both the right extension element and the left extension element and regardless of the adjustment mechanism.

[0137] 45. A head support unit as described in embodiment 44, wherein when the right and left mounting elements are articulated with the right and left support columns, in a completely inoperative state of the neutralization mechanism, the support body is freely displaceable toward one of the right and left extension elements and away from the other of the right and left extension elements.

[0138] 46. ​​A head support unit as described in embodiment 44 or 45, wherein the adjustment mechanism includes a right drive element and a left drive element arranged opposite each other along the lengths of the right extension element and the left extension element, respectively, and a drive gear including a drive portion configured to engage with the right drive element and the left drive element in the operating state of the neutralization mechanism and to displace the right extension element and the left extension element, respectively, upon rotation of the drive gear.

[0139] 47. A head support unit as described in embodiment 46, wherein rotation of the drive gear in a first direction involves adjustment of each of the right and left mounting elements toward an extended position, and rotation in a second, opposite direction involves adjustment of each of the right and left mounting elements toward a retracted position.

[0140] 48. A head support unit as described in embodiment 46 or 47, wherein the neutralization mechanism comprises a neutralization member configured to axially displace the drive portion along its rotation axis between an engaged position corresponding to an operative state, in which the drive portion is engaged with the right drive element and the left drive element, and a disengaged position corresponding to a non-operative state, in which the drive portion is disengaged from both the right extension element and the left extension element.

[0141] 49. A head support unit as described in embodiment 48, wherein the neutralizing member includes the drive portion, and the displacement of the drive portion is configured to be effected by axial displacement of the neutralizing member.

[0142] 50. A support unit according to any one of embodiments 46 to 49, wherein the drive portion is a pinion, and each of the right drive element and the left drive element is a rack.

[0143] 51. A head support unit as described in embodiment 50, wherein the neutralizing member is coaxially disposed within the drive gear.

[0144] 52. A head support unit described in any one of embodiments 45 to 51, wherein the adjustment mechanism is configured to simultaneously adjust the position of both the right mounting element and the left mounting element.

[0145] 53. A head support unit as described in embodiment 52, wherein the simultaneous adjustment of the positions of the right and left mounting elements is such that the right and left mounting elements are displaced along the same distance away from each other.

[0146] 54. A head support unit as described in any one of embodiments 43 to 53, further comprising a unit fixing mechanism that operates in conjunction with the adjustment mechanism to selectively fix the positions of the right extension element and the left extension element and prevent displacement of the right extension element and the left extension element relative to the support.

[0147] 55. A head support unit as described in embodiment 54, wherein the unit fixing mechanism is configured to fix the right mounting element and the left mounting element at any one of a plurality of intermediate positions between the extended position and the retracted position.

[0148] 56. A head support unit as described in embodiment 54 or 55, wherein the drive gear further comprises a latch portion selectively engageable with a lock portion of the support, the latch portion and the lock portion constituting at least part of a unit fixing mechanism, and the drive gear is configurable between a locked state in which the latch portion engages with the lock portion to prevent rotation of the drive gear, and an unlocked state in which the latch portion disengages from the lock portion to allow rotation of the drive gear and adjustment of the positions of the right and left mounting elements relative to each other.

[0149] 57. A head support unit as described in any one of embodiments 43 to 56, wherein the support has a longitudinal axis and the positions of the right and left mounting elements relative to each other are linearly adjustable along the longitudinal axis.

[0150] 58. A head support unit described in any one of embodiments 43 to 57, wherein the adjustment mechanism and neutralization mechanism extend at least partially within the support.

[0151] 59. A head support unit according to any one of claims 43 to 58, wherein the support is twistable relative to at least one of the right and left mounting elements.

[0152] 60. A head support unit as described in embodiment 59, wherein at least one of the right and left mounting elements is pivotally connected to its respective extension element to facilitate twisting of the support relative to the respective one of the right and left mounting elements.

[0153] 61. The right-hand mounting element is: A head support unit as described in embodiment 60, wherein the right and left mounting elements are pivotally connected to the right and left extension elements, respectively, to enable their independent pivotal displacement.

[0154] 62. A head support unit described in any one of embodiments 59 to 61, wherein the head support unit further comprises at least one auxiliary angle fixing mechanism configured to selectively fix the torsional angle between the support and each of the right and left support columns during twisting.

[0155] 63. A head support unit central portion for supporting the subject's head thereon, the head support unit central portion having a coupling configuration for enabling coupling to a head support assembly; A head support unit as described in any one of embodiments 44 to 62, wherein the head support unit further comprises two head support unit side sections, each of which is independently foldable about a longitudinal axis along a range of folding positions relative to the central section.

[0156] 64. A head support unit as described in embodiment 63, comprising a locking mechanism for (i) independently locking each of the head support unit sides in a desired folded position, or (ii) allowing free movement of the sides.

[0157] 65. A head support unit as described in embodiment 64, wherein each side of the head support unit includes a respective locking mechanism.

[0158] 66. A head support unit connectable to a head support assembly, comprising: a head support unit central portion for supporting the subject's head and including a coupling arrangement for enabling coupling to a head support assembly; two head support unit side sections, each independently foldable about a longitudinal axis along a range of folding positions relative to a central section; A head support unit comprising:

[0159] 67. A head support unit as described in embodiment 66, comprising a locking mechanism for (i) independently locking each of the head support unit sides in a desired folded position, or (ii) allowing free movement of the sides.

[0160] 68. A head support unit as described in embodiment 67, wherein each side of the head support unit includes a respective locking mechanism.

[0161] 69. The headrest member is a central portion and two side portions that are foldable relative to the central portion so as to allow the headrest member to assume a first state in which the side portions are spaced apart from each other by a first range and a second state in which the side portions are spaced apart from each other by a second range that is smaller than the first range; The headrest member is removably attachable to the head support unit; 70. A headrest member receivable within a head support unit according to any one of claims 64 to 69, wherein the head support unit comprises corresponding head support unit sides, the sides of the headrest member fitting over the head support unit sides such that the head support unit sides and the headrest member sides fold together.

[0162] 70. A headrest member as described in embodiment 69, further comprising a restraint member attached to the side and configured to rotate at least between an upper position and a lower position, wherein when in the lower position, the restraint member is configured to support the subject's forehead on the subject's head supported by the head support unit.

[0163] 71. The headrest member of embodiment 70, wherein displacement of the restraining member between its upper position and its lower position is configured to cause the headrest member to assume its first and second states, respectively.

[0164] 72. The headrest member of any one of embodiments 69 to 71, wherein the central portion comprises a central cushion and each side portion comprises a respective side cushion.

[0165] 73. The headrest member of embodiment 72, wherein the central cushion protrudes from a central plane defined by the central portion, and the side cushions protrude from sides defined by the side portions.

[0166] 74. The headrest member of embodiment 72 or 73, wherein the central cushion has a first portion protruding from the central surface to a first range and a second portion protruding from the central surface to a second range, the second range being greater than the first range.

[0167] 75. A headrest member according to any one of embodiments 72 to 74, wherein the central portion comprises a pair of support cushions, each member of the pair being disposed on a different side of the central cushion and spaced apart therefrom.

[0168] 76. The headrest member of embodiment 75, wherein each cushion of the pair projects from the central surface to a third extent greater than the second extent.

[0169] 77. The headrest member of embodiment 76, comprising a chin support unit removably coupled to the headrest member. [Brief explanation of the drawings]

[0170] In order to better understand the subject matter disclosed herein, and to illustrate how it may be carried out in practice, embodiments will now be described, by way of non-limiting example only, with reference to the accompanying drawings, in which:

[0171] [Figure 1A] 1 shows a rear perspective view of a folding wheelchair having a head support assembly with a head support unit attached thereto according to an example of the subject matter of the present disclosure. [Figure 1B] 1B is a diagram showing the wheelchair of FIG. 1A in a state where the head support unit is in a lower position than in FIG. 1A. [Figure 1C] 1B shows the wheelchair of FIG. 1A with the support of the head support unit tilted forward, aligned to the right, and twisted relative to the left and right mounting elements. FIG. [Figure 1D] 1B is a diagram showing the wheelchair of FIG. 1A in a state where the support for the head support unit is positioned to the right and lower than in FIG. 1A. [Figure 1E] FIG. 1B shows the wheelchair of FIG. 1A with the head support unit supports tilted forward and aligned to the right with different tilt angles for each strut and twisted at different angles relative to each of its right and left mounting elements, with the right and left struts tilted about their pitch axes relative to the right and left frame members. [Figure 1F] FIG. 1D is a front perspective view of the wheelchair of FIG. 1E. [Figure 1G] FIG. 1D is a rear view of the wheelchair of FIG. 1E. [Figure 2A] FIG. 1B shows a rear perspective view of the left coupler of the head support assembly of FIG. 1A. [Figure 2B] FIG. 2B is a cross-sectional view taken along line AA in FIG. 2A. [Figure 2C] FIG. 1F shows a rear perspective view of the left coupler of the head support assembly of FIG. 1E. [Figure 3A] 1B illustrates a rear perspective view of the head support unit of the head support assembly of FIG. 1A with its right and left mounting elements in an extended position and its support centered relative to the right and left mounting elements. [Figure 3B] FIG. 3B is an exploded view of the head support unit of FIG. 3A. [Figure 3C] FIG. 3B is a cross-sectional view taken along line BB in FIG. 3A. [Figure 3D] FIG. 3B is a cross-sectional view taken along line CC in FIG. 3A. [Figure 4A] 3B shows the head support unit of FIG. 3A with its support aligned to the right. [Figure 4B] FIG. 4B is a cross-sectional view taken along line DD in FIG. 4A. [Figure 5] FIG. 1D is a cross-sectional view taken along line EE in FIG. 1C. [Figure 6A] 6A-6E are schematic diagrams of non-limiting embodiments of a head support assembly showing different views and / or different folded states of the sides of the head support unit. Fig. 6A is a perspective view of the sides in an open state. Fig. 6B is a side view of the sides in an open state. Fig. 6C is a perspective view of the sides in a parallel neutral state. Fig. 6D is a perspective view of the sides in an asymmetric state. Fig. 6E is a perspective view of the sides in a closed state. [Figure 6B] 6A-6E are schematic diagrams of non-limiting embodiments of a head support assembly showing different views and / or different folded states of the sides of the head support unit. Fig. 6A is a perspective view of the sides in an open state. Fig. 6B is a side view of the sides in an open state. Fig. 6C is a perspective view of the sides in a parallel neutral state. Fig. 6D is a perspective view of the sides in an asymmetric state. Fig. 6E is a perspective view of the sides in a closed state. [Figure 6C]6A-6E are schematic diagrams of non-limiting embodiments of a head support assembly showing different views and / or different folded states of the sides of the head support unit. Fig. 6A is a perspective view of the sides in an open state. Fig. 6B is a side view of the sides in an open state. Fig. 6C is a perspective view of the sides in a parallel neutral state. Fig. 6D is a perspective view of the sides in an asymmetric state. Fig. 6E is a perspective view of the sides in a closed state. [Figure 6D] 6A-6E are schematic diagrams of non-limiting embodiments of a head support assembly showing different views and / or different folded states of the sides of the head support unit. Fig. 6A is a perspective view of the sides in an open state. Fig. 6B is a side view of the sides in an open state. Fig. 6C is a perspective view of the sides in a parallel neutral state. Fig. 6D is a perspective view of the sides in an asymmetric state. Fig. 6E is a perspective view of the sides in a closed state. [Figure 6E] 6A-6E are schematic diagrams of non-limiting embodiments of a head support assembly showing different views and / or different folded states of the sides of the head support unit. Fig. 6A is a perspective view of the sides in an open state. Fig. 6B is a side view of the sides in an open state. Fig. 6C is a perspective view of the sides in a parallel neutral state. Fig. 6D is a perspective view of the sides in an asymmetric state. Fig. 6E is a perspective view of the sides in a closed state. [Figure 7A] 7A and 7B are schematic diagrams of a non-limiting embodiment of a head support assembly, in which a head support unit is fitted with a head rest and a cushion member. [Figure 7B] 7A and 7B are schematic diagrams of a non-limiting embodiment of a head support assembly, in which a head support unit is fitted with a head rest and a cushion member. DETAILED DESCRIPTION OF THE INVENTION

[0172] Attention is initially directed to Figures 1A-1G of the drawings, which are directed to an example of a head support assembly according to the present disclosure, generally designated 10, mounted as an add-on to a seat in the form of a wheelchair of the general type, generally designated 14.

[0173] Wheelchair 14 is a folding wheelchair of the type comprising a right frame member 18 and a left frame member 20 articulated to one another by a folding X-shaped cross frame 24, each side frame mounted on large rear wheels 26 and front caster wheels 28, with a folding seat 30 and a folding backrest 32 extending between the right frame member 18 and the left frame member 20. Although a particular wheelchair is shown in the accompanying drawings, it will be understood that other types and configurations of wheelchairs may be used as well.

[0174] The head support assembly 10 includes a pair of struts, right strut 40 and left strut 42, articulated to the right frame member 18 by a right coupler 46 and articulated to the left frame member 20 by a left coupler 48. The right coupler 46 and left coupler 48 are similar and mirror images of each other. The right coupler 46 and left coupler 48 are configured to facilitate sliding displacement of the right strut 40 and left strut 42, respectively, between an upper position shown in FIG. 1A and a lower position shown in FIG. 1B, and to secure the right strut 40 and left strut 42 at any position between the upper and lower positions, as described below.

[0175] The head support assembly 10 further comprises a head support unit 50 having a support body 52 and a right mounting element 60 and a left mounting element 70 disposed on either side of the support body 52 along the longitudinal axis X. The right mounting element 60 and the left mounting element 70 are articulated to the tops of the right and left support columns 40 and 42, respectively.

[0176] The head support unit 50 is configured to support the head 13 of the user 12 seated in the wheelchair 14. As shown in FIG. 1A , the head restraint 2 is attached to the support 52 and positioned in front of the support 52. The head restraint 2 is configured to provide improved head and neck support to the user while seated in the wheelchair 14, for example, if the user 12 falls asleep or if the user is an individual with a physical disability. More specifically, the head restraint 2 is configured to prevent the user's head from falling forward and also to prevent the user's head from tilting to the left or right side. This provides comfortable and stable support for the user's head while seated in the wheelchair 14.

[0177] The head support assembly 10 is also configured to be used to hold the head upright when a seated user has dropped neck syndrome or any other condition affecting the neck muscles, such as ALS, CP, Parkinson's disease, muscular dystrophy, kyphosis, scoliosis, as well as conditions resulting from brain trauma, radiation therapy, and advanced degenerative spinal conditions. Use of the head support assembly can provide the user with comfort, pain relief, and the ability to perform daily activities, breathe, and eat properly.

[0178] 1A, the head restraint 2 is that disclosed in U.S. Patent No. 9,566,885. The head restraint 2 includes a pivotable restraining member 8 configured to prevent the head 13 from falling, and an attachment device 7 for removably attaching the head restraint 2 to a support 52. In use, when the head 13 is positioned in the head restraint 2, the restraining member 8 in its upper position can be positioned substantially above the head 13, and in its lower position the restraining member 8 is positioned in front of the user's forehead and supports the head.

[0179] As mentioned in the background of the subject matter of this disclosure, in order to use the head support assembly and head support unit of WO 2019 / 207580 when a seated user has drooping neck syndrome or any other condition that causes the head to tilt downward, the user's head must first be manually supported while applying significant force, and only once the head is properly positioned in a straight position can the head support unit be attached thereto. Furthermore, the head support unit can support the user's head when it is centered and not aligned to the right or left. This method of operating the head support assembly and head support unit of WO 2019 / 207580 may therefore require two or more operators who must apply a lot of force to support the user's head, and attaching the head to the head support unit can cause significant discomfort and even pain to the seated user.

[0180] 1D-1G, head support assembly 10 includes several repositioning mechanisms configured to spatially position and secure support 52 at different angles and orientations in the area above seat 30, as described in more detail below, allowing support 52 and attached head restraint 2 to be positioned as close as possible to head 13 of user 12. This capability of head support assembly 10 allows for proper treatment of users with downwardly tilted and / or sideways tilted heads.

[0181] Instead of carrying the user's head to the head support unit by manually lifting and stiffening the head before attaching it to the head support unit (as in WO 2019 / 207580), the head support unit 50 is configured to be displaced toward the user's head. This manipulation allows the head support unit 50 to be brought close to the user's head, allowing the head to be attached to the head support unit, and, if necessary, the entire head support unit can be tilted in the opposite direction (e.g., to the position of FIG. 1A ) along with the user's head, thereby stiffening the user's neck and back and lifting the head. In this case, the bottoms of the right and left support columns can be used as levers to tilt the head in the opposite direction. Below, a description is provided to explain in detail how the head support unit 50 can be spatially manipulated to different tilt angles and alignment positions.

[0182] The right coupler 46 and the left coupler 48 define a pitch axis P extending therebetween, the left frame member 20 and the right frame member 18 each define a roll axis R1 and R2, respectively, and the struts 40 and 42 each define their respective longitudinal axes L1 and L2.

[0183] The head support assembly 10 has five independent displacement mechanisms, which allow the spatial position and orientation of the head support unit 50 and its support 52 to be changed in five different independent degrees of freedom: The first displacement mechanism allows tilting of the struts 40 and 42 around the pitch axis P. a second displacement mechanism allows the columns 40 and 42 to tilt about their respective roll axes R1 and R2; a third displacement mechanism allowing the columns 40 and 42 to be slidably displaced along their respective axes L1 and L2; The fourth displacement mechanism allows the support 52 to be displaced along the longitudinal axis X without displacing the left and right columns; The fifth displacement mechanism allows the support 52 to be twisted independently relative to the right and left mounting elements 60, 70.

[0184] The first three displacement mechanisms are associated with the structure of each of the right and left couplers 46, 48, and allow tilting and displacement of the columns 40 and 42. The structure of one of the couplers, namely the left coupler 48, will now be described with particular reference to Figures 2A-2C.

[0185] The left coupler 48 is comprised of two parts: a mounting member 110 articulatable to the left frame member 20, and a strut receiving member 120 configured to restrain the left strut 42. The strut receiving member 120 is pivotable relative to the mounting member 110 to facilitate tilting of the left strut 42 about the pitch axis P and to provide a first displacement mechanism.

[0186] The mounting member 110 includes a primary angle locking mechanism 111 configured to selectively constrain the angular position of the mounting member 110 relative to the support member receiving member 120 when the left support column 42 tilts about the pitch axis P, thereby fixing the tilt angle β between the longitudinal axis L1 of the left support column 42 and the backrest plane B defined by the backrest 32 of the wheelchair 14 (as shown in FIG. 1C ).

[0187] Primary angular locking mechanism 111 includes an actuating button 113 and a spring (not shown) biased actuating member 112 that is linearly displaceable within a housing of mounting member 110 along pitch axis P by a blocking member 114. Column receiving member 120 includes a pivot member 121 that extends within actuating member 112. As shown in FIG. 2B , actuating member 112 includes teeth 112′ configured to be received within respective recesses (not shown) of blocking member 114 to block pivotal displacement of actuating member 112 along with pivot member 121.

[0188] When the actuating member 112 is displaced by pressing the actuating button 113, the tooth 112' disengages from the recess in the blocking member 114, and the left support column 42 can tilt together with the support column receiving member 120 about the pitch axis P. To fix the new tilt angle between the left support column 42 and the backrest plane B, the operator must stop pressing the actuating button 113, which then returns to its normal position, fixing the angular position between the actuating member 112 and the blocking member 114, resulting in the configuration shown in, for example, FIG. 2C.

[0189] The support column receiving member 120 has a height fixing mechanism 122 configured to selectively restrain the left support column 42 at different positions along the longitudinal axis L1. The height fixing mechanism 122 constitutes a third displacement mechanism and is disposed opposite the primary angle fixing mechanism 111.

[0190] Height fixing mechanism 122 includes pedal 123 and friction member 124. Pedal 123 is pivotable about pedal axis 123 and is biased by a compression spring (not shown) toward a normal position shown in FIG. 2B in which the bottom of the pedal presses against friction member 124, which in turn presses against left support post 42, fixing its position within support post receiving member 120.

[0191] To change the height of the left support column 42 and facilitate its sliding displacement, the operator must press on the top of the pedal 123. This causes the compression spring to displace the friction member 124 outward, thereby disengaging it from the left support column 42.

[0192] The mounting member 110 includes an embracing portion 130 configured to articulate the left coupler 48 and its left strut 42 to the left frame member 20 .

[0193] The holding portion 130 is configured with a tensioning mechanism (not shown) in the form of a bolt and nut that is configured to control the tension applied by the holding portion 130 to the left frame member 20 to control the ability of the left support column 42 to undergo rotational displacement about the roll axis R1.

[0194] The embracing portion 130 is in the form of a bridge shaped and sized to fit over a post received in the coupler. One side of the bridge may be pivotally coupled to the coupler to allow switching between an embracing state in which the bridge joins the coupler on its two sides, and an open state in which the bridge is in a pivoted position to allow removal or insertion of a frame member into the embracing area defined between the coupler and the embracing portion.

[0195] The ability of the left coupler 48 to rotate about roll axis R1 constitutes a second displacement mechanism.

[0196] As shown in Figures 1E to 1G, by rotating the left support column 42 around both the pitch axis P and the roll axis R1, the support column receiving member 120 can be pivoted relative to the mounting member 110 and the mounting member 110 can be rotated relative to the left frame member 20 simultaneously.

[0197] Here, to explain the structure and operation of the head support unit 50, and particularly to explain the operation methods of the fourth and fifth displacement mechanisms, reference will be made to FIGS. 3A to 3D, 4A, 4B and 5.

[0198] 3A-3D, support 52 of head support unit 50 is centrally positioned relative to wheelchair 14. In FIGS. 4A and 4B, support 52 is aligned and displaced to the right side of wheelchair 14 by a fourth displacement mechanism, as described below. In FIG. 5, support 52 is twisted relative to right and left support columns 40, 42.

[0199] The head support unit 50 includes an adjustment mechanism 80 configured to selectively adjust and fix the positions of the right and left mounting elements 60, 70 relative to one another between an extended position (shown in FIGS. 5A and 5B) and a retracted position (not shown). The operating principle of the adjustment mechanism 80 is similar to the adjustment mechanism of WO 2019 / 207580.

[0200] In particular, the positions of the right and left mounting elements 60, 70 are adjusted by simultaneously linearly displacing them along the longitudinal axis X toward and away from each other.

[0201] As shown in FIG. 1A , the right and left support columns 40 and 42 extend vertically upward and parallel to each other, defining a fixed distance between them. When the right and left support columns 40 and 42 are attached to the right and left frame members 18 and 20 and positioned perpendicular and parallel to each other, the distance between them is determined by the width of the wheelchair 14, particularly the configuration of the wheelchair 14 and the distance between the right and left frame members 18 and 20. This distance may vary from seat to seat or may depend on the location at which the left and right support columns articulate to the side frames of a particular seat. Thus, the right and left mounting elements 60 and 70 are adjustable relative to each other to removably attach the head support unit 50 to the right and left support columns 40 and 42 and to fixably fit the distance between them and between the right and left frame members 18 and 20, respectively. This adjustment allows the right and left mounting elements 60 and 70 to fixably occupy any one of a number of intermediate positions between the extended and retracted positions. In the example of Figures 1A and 1B, the right and left mounting elements 60, 70 are fixedly adjusted to an intermediate position that matches the distance between the right and left support columns 40, 42, which is determined by the distance between the right and left frame members 18, 20.

[0202] Reference is now made in particular to Figures 3A to 3D, which show head support unit 50 and its different parts.

[0203] The adjustment mechanism 80 extends at least partially within the support 52 and is configured to simultaneously displace the right and left mounting elements 60, 70 relative to each other and relative to the support 52. The simultaneous adjustment of the positions of the right and left mounting elements 60, 70 is such that, upon operation of the adjustment mechanism 80, the right and left mounting elements 60, 70 are displaced the same distance. Further, in the example of FIGS. 3A-3D , the support 52 is symmetrical with respect to the right and left mounting elements 60, 70, such that the right and left mounting elements are equally spaced from the center of the support 52 in their various positions between the extended and retracted positions. The adjustment mechanism 80 is operable by an operator to increase or decrease the distance between the right and left mounting elements 60, 70, thereby adjusting and displacing both the right and left mounting elements 60, 70 toward either the extended and / or retracted positions with a single user operation.

[0204] 2, the right and left mounting elements 60 and 70 are connected to either side of the support 52 via right and left extension elements 62 and 72, respectively, both of which are slidable within tunnels 57 and form part of an adjustment mechanism 80. The adjustment mechanism 80 is configured to displace and fix the right and left extension elements 62 and 72 relative to the support 52, thereby displacing and fixing the right and left mounting elements 60 and 70 in a plurality of positions.

[0205] The right extension element 62 has a right elongated opening 63 formed therein, and the upper right rim 64 has a right drive element in the form of teeth extending therefrom that constitutes an upper rack 84. The left extension element 72 has a left elongated opening 73 formed therein, and the lower left rim 74 has a left drive element in the form of teeth extending therefrom that constitutes a lower rack 86. The adjustment mechanism 80 includes an upper rack 84, a lower rack 86, and a drive gear 87 that engages both the upper rack 84 and the lower rack 86 and includes a drive portion in the form of a pinion 88 that extends through the right elongated opening 63 and the left elongated opening 73.

[0206] The drive gear 87 includes a rotatable handle 89 configured to be grasped by an operator and rotated in a clockwise direction to adjust the left and right mounting elements 60 and 70 from the retracted position toward the extended position, and rotated in a counterclockwise direction to adjust the right and left mounting elements 60 and 70 from the extended position toward the retracted position.

[0207] As described above, the adjustment mechanism 80 is further configured to selectively fix the positions of the right mounting element 60 and the left mounting element 70 relative to each other. Thus, the head support unit 50 includes a unit fixing mechanism 90 configured to work in conjunction with the adjustment mechanism 80 to normally fix the right mounting element 60 and the left mounting element 70 at any one of a plurality of intermediate positions between the extended position and the retracted position, thereby preventing displacement relative to the support body 52.

[0208] The unit locking mechanism 90 has tooth-like latching portions 92 (shown in FIG. 3C) formed in the handle 89 that are selectively engageable with locking portions 94 formed as recesses in the support 52 (shown in FIGS. 2, 3C, 3D, and 4C). The teeth of the locking portion 94 are designed to be complementary to the recesses in the latching portion 92 so that when the locking portion 94 is displaced into engagement with the latching portion 92, the locking portion 94 is flush with the latching portion 92 and prevented from moving. This state of the unit locking mechanism 90 is shown in all figures and is considered the locked state of the unit locking mechanism 90. The number of teeth and recesses and the spacing between them determine the number of discrete positions (e.g., intermediate positions) and the difference between the positions.

[0209] Therefore, the unit fixing mechanism 90 is a locked state (shown in all figures) in which the latch portion 92 engages with the lock portion 94 to prevent rotation of the drive gear 87 and fix the relative positions of the left and right mounting elements 60, 70; and an unlocked state (not shown) in which the latch portion 92 and the lock portion 94 are disengaged and the drive gear 87 is able to rotate.

[0210] The handle 89 is spring-biased toward a normally locked state by a tension spring (not shown), and the operator must apply a pulling force against the force of the tension spring to pull the handle 89 and cause the locking mechanism to move to its unlocked state.

[0211] The unit locking mechanism 90 is configurable between a locked state and an unlocked state by an operator pulling the handle 89 toward and away from the support 52, thereby slidably displacing the drive gear 87 perpendicular to the longitudinal axis X toward and away from the support.

[0212] For example, to displace the right and left mounting elements 60, 70 from the retracted position in which the unit securing mechanism 90 is locked, the handle 89 must first be pulled by the user away from the support 52. This places the unit securing mechanism 90 in an unlocked state. Only in this unlocked state does the latch portion 92 disengage from the lock portion 94, allowing the operator to rotate the handle 89 clockwise to rotate the drive gear 87. During the rotation of the handle 89, the distance between the right and left mounting elements 60, 70 decreases, and they pass through several intermediate positions. At any intermediate position where the desired distance is achieved, the handle 89 is pushed toward the support 52, placing the unit securing mechanism 90 in its locked state.

[0213] The head support unit 50 includes a counteracting mechanism 95 that operates in conjunction with the adjustment mechanism 80 to selectively allow free displacement of the support 52 relative to the right extension element 62 and the left extension element 72. The counteracting mechanism 95 thus allows the adjustment mechanism 80 to be counteracted, which provides an additional degree of freedom for properly positioning the support 52 relative to the head of a seated user.

[0214] The neutralization mechanism 95 comprises a neutralization member 96 having a drive gear 87 at its distal end and a neutralization button 97 at its proximal end. The neutralization member 96 is positioned coaxially within the handle 89 and is spring-loaded by a compression spring 99.

[0215] The counteracting mechanism 95 is switchable between an operative state in which the adjustment mechanism 80 operates to displace both the right extension element 62 and the left extension element 72, and an inoperative state in which the support body 52 is freely displaceable relative to both the right extension element 62 and the left extension element 72 independently of the adjustment mechanism 80. In the operative state of the counteracting mechanism 95 shown in Figures 3A, 3C, and 3D, the unit fixing mechanism 90 must be used as described above to displace the right extension element 62 and the left extension element 72.

[0216] The neutralizing member 96 is configured to be axially displaceable along its rotational axis together with the drive gear 87 between an engaged position (shown in Figures 3C and 3D) corresponding to an operational state in which the pinion 88 engages with the upper rack 84 and the lower rack 86, and a disengaged position (shown in Figures 1D, 4A and 4B) corresponding to an inoperative state in which the pinion 88 disengages from both the upper rack 84 and the lower rack 86.

[0217] The neutralizing member 96 is displaced from the engaged position to the disengaged position by the operator pressing and holding the neutralizing button 97. When the operator stops pressing the neutralizing button 97, the neutralizing member 96 automatically attempts to return to its normally engaged position. As a result, the adjustment mechanism 80 can be used to simultaneously displace the right mounting element 62 and the left mounting element 72, as described above.

[0218] In summary, when the right and left mounting elements 60 and 70 are articulated with the right and left support columns 40 and 42, respectively, in the non-operating state of the neutralization mechanism 95, the support body 52 can be freely aligned and displaced toward one of the right and left extension elements 62 and 72 and away from the other of the right and left extension elements 62 and 72.

[0219] 1D, 4A, and 4B, while the neutralization button 97 is pressed by the operator, the support 52 is displaced maximally to the right by using the neutralization mechanism 95 (constituting the fourth displacement mechanism) so as to be adjacent to the right mounting element 60. As shown in FIG. 4B, the neutralization member 96 is displaced axially along its rotational axis together with the drive gear 87 to a disengaged position corresponding to an inoperative state in which the pinion 88 is disengaged from both the upper rack 84 and the lower rack 86. In this position, the head support assembly can be used to mount an occupant's head to the head support assembly with the head tilted to the right.

[0220] Reference is now made to FIGS. 1C and 5, which illustrate a fifth displacement mechanism that can facilitate twisting of the support 52 relative to the right and left mounting elements 60, 70.

[0221] This mechanism is provided by a right extension element 62 pivotally connected to the right mounting element 60 by a right pivot member (not shown) and a left mounting element 70 pivotally connected to the left extension element 72 by a left pivot member 71 to facilitate twisting of the support body 52 relative to the right mounting element 60 and the left mounting element 70.

[0222] The head support unit 50 is also provided with a right auxiliary angle locking mechanism 66 and a left auxiliary angle locking mechanism 76. The left auxiliary angle locking mechanism 76 (shown most clearly in FIG. 5 ) is configured to selectively lock the torsion angle μ between the support body 52 and the longitudinal axis L1 during twisting. The left auxiliary angle locking mechanism 76 includes a spring-loaded pin 77 configured to be selectively received in one of a plurality of recesses 78. The pin 77 is connected to a push button 79 configured to displace the pin 77 up or down to selectively lock the torsion angle μ.

[0223] To summarize the above-described method of operation of the five displacement mechanisms, reference is now made to Figures 1E-1G, where all of these mechanisms are used to place support member 52 in a complex spatial orientation.

[0224] The first displacement mechanism is used to tilt the right support column 40 about the pitch axis P to an inclination angle β1 between the longitudinal axis L2 and the backrest plane B, and tilt the left support column 42 about the pitch axis P to an inclination angle β2 between the longitudinal axis L1 and the backrest plane B. This tilt of the right support column 40 and the left support column 42 is achieved by pivotal rotation of the support column receiving members of the right coupler 46 and the left coupler 48 when using their respective primary angle locking mechanisms.

[0225] A second displacement mechanism is used to tilt columns 40 and 42 about their respective roll axes R1 and R2. As shown in FIG. 1G, this tilting creates a roll angle α1 between longitudinal axis L1 and vertical axis V1.

[0226] A third displacement mechanism is used to properly position the height of the columns 40 and 42 along their respective axes L1 and L2 by using height fixing mechanisms on the right and left couplers 46 and 48, respectively.

[0227] The fourth displacement mechanism utilizes the neutralization mechanism 95 of the head support unit 50 to move the support body 52 as close as possible to the right support column 40 .

[0228] The fifth displacement mechanism is used to twist the support 52 relative to the left mounting element 70 and its longitudinal axis L1 and fix the angle therebetween at a twist angle μ1 (shown in Figures 1F and 1G).

[0229] Reference is now made to Figures 6A-6E, which are schematic illustrations of a non-limiting embodiment of a head support assembly of the present disclosure. This embodiment differs from that depicted in Figures 1-5 in that the head support unit 610 of the head support assembly 600 includes two head support unit sides 612 and 614 extending laterally from a hinge 611 that connects the head support unit sides to a central portion 613 of the head support unit 610. The head support unit sides 612 and 614 are foldable about two parallel axes L3 and L4, respectively. Axes L3 and L4 are parallel to the longitudinal axes L1 and L2 when the support strut is in a neutral position. Each head support unit side 612 and 614 is foldable along a range of folding positions between a most open position, in which each side is in its most folded position facing away from the other side, as seen in FIGS. 6A and 6B, and a most closed position, in which each side is in its most folded position facing toward the other side, as seen in FIG. 6E. Between the most open and closed positions, each head support unit side can be adjusted to multiple folding states independent of the folding states of the other head support unit sides. Each head support unit side 612 and 614 is associated with a respective locking mechanism 616 and 618, respectively. Each locking mechanism is configured to toggle between two states. The first state (i) allows each head support unit side to be locked in a folded position independent of the folded positions of the other head support unit sides, and the second state (ii) allows free folding movement of each head support unit side independent of the other folded states of the head support unit sides. Figure 6C shows the head support unit sides in parallel, neutral folded positions. Figure 6D shows an asymmetric folded position of two head support unit sides, i.e., one of the head support unit sides is in one folded position and the second head support unit side is in a different folded position, i.e., at a different folded angle relative to the neutral position.

[0230] Additionally, in this embodiment, head support assembly 600 includes two mounting elements 615 and 617 that are rotatable ±90° about horizontal axis X from a neutral position shown in Figures 6A-6E. Rotation of the mounting elements affects the angle of the plane defined by central portion 613 relative to the ground.

[0231] The struts 619 and 621 are telescoping, allowing for more efficient use of the head support assembly and for more compact storage of the head support assembly.

[0232] The head support unit 610 is coupled to the head support assembly 600 via four coupling members 623 in the form of screws. This coupling configuration allows the head support unit coupled to the head support assembly to be interchangeable. Thus, a head support unit can be personalized for a specific individual and coupled to any head support assembly via the coupling members. Furthermore, one head support assembly can be coupled to many head support units, allowing it to serve many different individuals over a period of time.

[0233] The head support unit is configured to have a headrest member attached, which is typically a cushioned, soft structure upon which the subject's head rests. A head support unit with the attached headrest member is shown in FIGS. 7A-7B. Headrest member 730 includes a tab 732 that is received in a slit 720 formed in a central portion 722 of head support unit 710. Corresponding sides 734 and 736 of headrest member 730 are configured to mate with head support unit sides 712 and 714, respectively. Sides 734 and 736 of headrest member 730 and the head support unit sides are foldable together, i.e., a folded position of one results in a similar folded position of the other. Headrest member 730 further comprises a restraint member 738 attached to sides 734 and 736 and configured to rotate between at least an upper position and a lower position, wherein when in the lower position, restraint member 738 is configured to support the subject's forehead against the subject's head supported by head support unit 710. Displacement of restraint member 738 between its upper position and its lower position is configured to urge the headrest member into its first and second states, respectively.

[0234] The headrest member 730 is made of a flexible cushioning material configured to provide flexible support for the subject's head. The headrest member 730 is formed with a plurality of cushions. A central cushion 742 is formed in a central portion 740 of the headrest member 730 and protrudes from the central portion 740. As best seen in FIG. 7A , the central cushion 742 includes a first portion 744 that protrudes to a first height and a second portion 746 that protrudes to a second height greater than the first height. The contours of the central cushion 742 are designed to fit the subject's occipital bone, and thus the second portion 746 is configured to conform to the lower part of the subject's head. The central portion 740 further includes a pair of support cushions 748, each positioned on a different side of the second portion 746 of the central cushion 742. Each of the support cushions 748 protrudes to a third height greater than the second portion 746.

[0235] Each of the side portions 734 and 736 of the headrest member 730 is formed with a respective side cushion 750 and 752 that is separated from the central portion 742 and central cushion 744. The separation portions 754 and 756 between the central cushion 744 and the side cushions 750 and 752 are relatively thin to allow the side cushions to fold relative to the central cushion along with the head support unit sides.

Claims

1. 1. A head support assembly attachable to a seat having a right frame member and a left frame member, the head support assembly comprising: a right support column and a left support column; a right coupler and a left coupler articulatable to the right frame member and the left frame member, respectively, and configured to independently restrain the right strut and the left strut, respectively, to facilitate at least partial tilt of the strut about a pitch axis extending between the right coupler and the left coupler; a head support unit articulatable to the upper right portion of the right column and the upper left portion of the left column; Equipped with the head support unit comprises a right mounting element articulatable at the upper right portion, a left mounting element articulatable at the upper left portion, and a support disposed between the right mounting element and the left mounting element, the support being twistable relative to at least one of the right mounting element and the left mounting element.

2. 2. The head support assembly of claim 1, wherein the right and left couplers are articulatable to the right and left frame members, respectively, and are configured to independently constrain the right and left struts, respectively, so as to also facilitate selective sliding displacement of the struts along their longitudinal axes.

3. 3. The head support assembly of claim 1 or 2, wherein the right coupler and the left coupler each comprise a mounting member articulatable to the respective right and left frame members, and a strut receiving member configured to restrain the respective right and left strut and pivotable relative to the mounting member to facilitate the tilting of the struts about the pitch axis.

4. 4. The head support assembly of claim 3, wherein the mounting members are articulatable to the respective right and left frame members to facilitate rotational displacement of the respective struts about the roll axis of the respective frame members.

5. 5. The head support assembly of claim 4, wherein the mounting members comprise cradling portions configured to effect the articulation by embracing their respective right and left frame members, the cradling portions comprising tensioning mechanisms configured to control tension applied by the embracing portions to the respective right and left frame members to control the ability of the respective struts to effect the rotational displacement relative to the respective right and left frame members.

6. 6. A head support assembly as claimed in claim 4 or 5, when dependent on claim 2, wherein the pivotal movement of the strut receiving member relative to the mounting member and the rotational displacement of the mounting member relative to the respective right and left frame members are configured to occur simultaneously to facilitate displacement of the respective struts about both the pitch axis and the roll axis.

7. 7. The head support assembly of claim 3, wherein at least one of the right coupler and the left coupler includes a primary angle locking mechanism configured to selectively constrain the angular position of the mounting member relative to the support pillar receiving member during the tilt, thereby fixing the tilt angle between the respective support pillar and a backrest plane defined by the seat back.

8. 8. The head support assembly of claim 3, wherein the column receiving member comprises a height locking mechanism configured to selectively restrain each column at different positions relative to the column receiving member along the longitudinal axis.

9. the right and left mounting elements are disposed on opposite sides of the support via right and left extension elements, respectively, and at least one of the right and left mounting elements is pivotally connected to its respective extension element to facilitate the twisting of the support relative to a respective one of the right and left mounting elements; 2. The head support assembly of claim 1, wherein the head support unit comprises an adjustment mechanism configured to selectively adjust the positions of the right and left mounting elements relative to one another by displacing the right and left extension elements between a retracted position and an extended position, respectively, and a countermeasure mechanism operative with the adjustment mechanism to selectively allow free displacement of the support relative to at least one of the right and left extension elements.

10. the neutralization mechanism is switchable between an operative state in which the adjustment mechanism operates to displace both the right extension element and the left extension element, and a completely inoperative state in which the support body is freely displaceable relative to both the right extension element and the left extension element and independent of the adjustment mechanism; the adjustment mechanism includes right and left drive elements disposed opposite each other along the lengths of the right and left extension elements, respectively; and a drive gear including a drive portion configured to engage the right and left drive elements in the operative state of the neutralization mechanism, the drive gear configured to displace the right and left extension elements, respectively, upon rotation of the drive gear; 10. The head support assembly of claim 9, wherein the neutralizing mechanism comprises a neutralizing member configured to axially displace the drive portion along its axis of rotation between an engaged position corresponding to the operative state, in which the drive portion is engaged with the right and left drive elements, and a disengaged position corresponding to the non-operative state, in which the drive portion is disengaged from both the right and left extension elements.

11. 11. The head support assembly of claim 10, wherein the head support unit further comprises a unit fixing mechanism that operates with the adjustment mechanism to selectively fix the positions of the right extension element and the left extension element and prevent displacement of the right extension element and the left extension element relative to the support.

12. 12. The head support assembly of claim 11, wherein the drive gear further comprises a latch portion selectively engageable with a lock portion of the support body, the latch portion and the lock portion constituting at least a part of the unit securing mechanism, and the drive gear is configurable between a locked state in which the latch portion engages with the lock portion to prevent rotation of the drive gear, and an unlocked state in which the latch portion disengages from the lock portion to allow rotation of the drive gear and adjustment of the positions of the right and left mounting elements relative to each other, respectively.

13. 13. The head support assembly of claim 1, wherein the head support unit is configured to receive a headrest member having a central portion and two side portions, the two side portions being foldable relative to the central portion to enable the headrest member to assume a first state in which the side portions are spaced apart from each other by a first range and a second state in which the side portions are spaced apart from each other by a second range that is smaller than the first range.

14. the headrest member further comprises a restraint member attached to the side portion and configured to rotate at least between an upper position and a lower position, and when in the lower position, the restraint member is configured to support the forehead of the subject at a position where the subject's head is supported by the head support unit; 14. The head support assembly of claim 13, wherein the head support unit includes corresponding head support unit sides, and the sides of the head rest member are configured to be attached to or fit within the head support unit sides such that the sides of the head rest member and the head support unit sides fold together.

15. 15. The head support assembly of claim 14, wherein the head support unit includes a locking mechanism for (i) independently locking each of the head support unit sides in a desired folded position, or (ii) allowing free movement of the sides.

16. the central portion includes a central cushion and each side portion includes a respective side cushion, the central cushion protruding from a central plane defined by the central portion and the side cushions protruding from lateral sides defined by the side portions, the side cushions protruding more than the central cushion to conform to the shape of the subject's skull; 16. The head support assembly of claim 13, wherein the central cushion comprises a first portion that protrudes from the central surface to a first extent and a second portion that protrudes from the central surface to a second extent, the second extent being greater than the first extent, and the central portion comprises a pair of support cushions, each member of the pair being located on a different side of the central cushion and spaced apart therefrom.

Images