WO2024253601A1 - Structure de support de siège inclinable à pivots multiples - Google Patents

Structure de support de siège inclinable à pivots multiples Download PDF

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Publication number
WO2024253601A1
WO2024253601A1 PCT/TH2024/000002 TH2024000002W WO2024253601A1 WO 2024253601 A1 WO2024253601 A1 WO 2024253601A1 TH 2024000002 W TH2024000002 W TH 2024000002W WO 2024253601 A1 WO2024253601 A1 WO 2024253601A1
Authority
WO
WIPO (PCT)
Prior art keywords
seat
assembly
support structure
support
seat support
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Ceased
Application number
PCT/TH2024/000002
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English (en)
Other versions
WO2024253601A4 (fr
Inventor
Klaus Jürgen KUMMER
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Chaichana Suladda
Original Assignee
Chaichana Suladda
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Chaichana Suladda filed Critical Chaichana Suladda
Priority to CN202480029856.3A priority Critical patent/CN121099936A/zh
Publication of WO2024253601A1 publication Critical patent/WO2024253601A1/fr
Publication of WO2024253601A4 publication Critical patent/WO2024253601A4/fr
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

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Classifications

    • A—HUMAN NECESSITIES
    • A47—FURNITURE; DOMESTIC ARTICLES OR APPLIANCES; COFFEE MILLS; SPICE MILLS; SUCTION CLEANERS IN GENERAL
    • A47C—CHAIRS; SOFAS; BEDS
    • A47C1/00—Chairs adapted for special purposes
    • A47C1/02—Reclining or easy chairs
    • A47C1/031—Reclining or easy chairs having coupled concurrently adjustable supporting parts
    • A47C1/032—Reclining or easy chairs having coupled concurrently adjustable supporting parts the parts being movably-coupled seat and back-rest
    • A47C1/03255—Reclining or easy chairs having coupled concurrently adjustable supporting parts the parts being movably-coupled seat and back-rest with a central column, e.g. rocking office chairs
    • A—HUMAN NECESSITIES
    • A47—FURNITURE; DOMESTIC ARTICLES OR APPLIANCES; COFFEE MILLS; SPICE MILLS; SUCTION CLEANERS IN GENERAL
    • A47C—CHAIRS; SOFAS; BEDS
    • A47C1/00—Chairs adapted for special purposes
    • A47C1/02—Reclining or easy chairs
    • A47C1/031—Reclining or easy chairs having coupled concurrently adjustable supporting parts
    • A47C1/032—Reclining or easy chairs having coupled concurrently adjustable supporting parts the parts being movably-coupled seat and back-rest
    • A47C1/03261—Reclining or easy chairs having coupled concurrently adjustable supporting parts the parts being movably-coupled seat and back-rest characterised by elastic means
    • A47C1/03272—Reclining or easy chairs having coupled concurrently adjustable supporting parts the parts being movably-coupled seat and back-rest characterised by elastic means with coil springs
    • A—HUMAN NECESSITIES
    • A47—FURNITURE; DOMESTIC ARTICLES OR APPLIANCES; COFFEE MILLS; SPICE MILLS; SUCTION CLEANERS IN GENERAL
    • A47C—CHAIRS; SOFAS; BEDS
    • A47C1/00—Chairs adapted for special purposes
    • A47C1/02—Reclining or easy chairs
    • A47C1/031—Reclining or easy chairs having coupled concurrently adjustable supporting parts
    • A47C1/032—Reclining or easy chairs having coupled concurrently adjustable supporting parts the parts being movably-coupled seat and back-rest
    • A47C1/03261—Reclining or easy chairs having coupled concurrently adjustable supporting parts the parts being movably-coupled seat and back-rest characterised by elastic means
    • A47C1/03283—Reclining or easy chairs having coupled concurrently adjustable supporting parts the parts being movably-coupled seat and back-rest characterised by elastic means with fluid springs

Definitions

  • the present invention relates to a multi pivotal horizontal rotating seat support structure or device that is commonly used in office chairs to support the weight of a person, in particular a seated person and especially to an adjustable support structure or device, that is adjustable to alter the seating or reclining position of a subject resting on the structure particularly from an inclined forward position to a rearward reclined position.
  • an adjustable support structure or device that is adjustable to alter the seating or reclining position of a subject resting on the structure particularly from an inclined forward position to a rearward reclined position.
  • Support structures for use in offices and other situations, which allow altering the seat height, seat inclination and reclining position of a subject are known, (Pat. US7028580A, Pat. WO 01/8719 Al, Pat. US09356998B1, Pat. US11620043B1, Pat. US8944507).
  • many of the known forms of support structures suffer from some disadvantages, either by not acknowledging the latest status of biomechanical science or focus only on some limited parts of the ergonomic implications of the seated person.
  • the current embodiment of the invention is primarily, but not exclusively, focused on an office and task chair application.
  • the office chair comprises eight portions:
  • a mobile base assembly portion (foot base)
  • Portion (A) supports the upper portions (B - H), can be equipped with glides or swiveling wheels for mobility while seated.
  • Portion (B) contains a mechanical or pneumatic device to allow swiveling and a height adjustment of the upper portions (C - H).
  • Portions (C) and (D) form the heart and center of this invention and enable an articulated movement of a person from an inclined and forward leaning seated position to a lower backward reclined position, which can be secured infinitely by the use of a mechanical, pneumatic or electric actuated means.
  • Portion (E) is attached to the height adjustable backrest (G) to maintain a constant equal and proportional correct height for the lower arm of a seated person.
  • Portion (F) is configured to support the portions G, E & H and is transverse pivotally hinged to portion (C) to allow for a reverse synchronized alteration of the backrest angle with the imaginative pivotal fulcrum in the hip joint.
  • the present invention aims to provide a support structure, which recognizes and supports the current state of anthropological and biomechanical facts.
  • the current invention aims to allow and to encourage a ‘seated’ person into shifting the seating position upward and forward in a convenient an easy understandable and a self-explanatory way.
  • the present invention generally provides a support structure for supporting a person in a seated position, the support structure comprising: a linear for- and upward or back- and downward moving apparatus to carry the weight of a person seated upon the support structure; a frame attached to the support structure to support the upper body portion, when leaning back (backrest), that supports angle variations of the seated person forward or backward through a reverse synchronized movement;
  • the support structure is incorporated into a chair, in particular a task or office chair, on which the subject may recline backward or ascent forward in a linear single movement, whereby the transverse pivotal axis of the motion is the knee joint as the reference fulcrum, meaning, while the upper thigh is evenly supported and in permanent contact with the seat pan surface in its entire length, the legs remain resting square on the floor.
  • the compulsory dynamic movement allows the seated person to maintain throughout the motion a torso-to-thigh angle larger than 90 degrees.
  • Incline and recline of the seat pan is achieved and controlled by two pairs of transverse connected pivotally hinged levers directly under the seat pan, which force the seat pan to move on a compulsory hinged parallelogram with uneven legs, also called parallelepiped, to describe an imaginative curved path with the fulcrum in the knee joint.
  • the seat pan and the parallelepiped levers need to be supported by means of a force to lift a weight.
  • a force to lift a weight There are several options for this force available, such as a pneumatic cylinder or gas spring, a transverse torsion bar or an electric actuator.
  • the adjustable support structure When installed with a lifting force in the form of a coil spring or a transverse torsion bar, the adjustable support structure would be a floating device, meaning, that with a corresponding adjustment of the spring to the weight of the seated person, the adjustable support structure would allow balancing the seated body and by changing the center of gravity in the upper body forward to move into a forward elevated posture or, by leaning backward, into a relaxed backward reclining posture in a compulsory singular ‘floating’ movement without obstruction or effort.
  • the said adjustable support structure comprises a means for securing (locking) in the form of a lockable gas spring.
  • the ultimate solution for the uplifting movement is an electric actuator, which replaces all the other solutions and allows for a precise and controlled modulation of the desired seat movement.
  • the adjustable support structure would have only one releasable locking/detent means for the entire structure of the seat rest support and the arrest of the seat pan (D) movement in any inclination.
  • a second means of lever or other device would be provided for the height adjustment and detention of the means of the uplifting force in portion (B) of the current embodiment.
  • the limitations of the terminal positions of the backward and forward movement of the seat pan will be controlled by limiting the movement of the weight lifting device through a travel limit extension of the locking device employed.
  • the present embodiment is designed to accommodate the most common seating situations in the current office environment. It also encourages a solution for the importance, to employ height adjustable tables in the office working environment aimed to solve the back pain problems, by switching effortlessly between a low sitting position and an elevated high up and articulate forward leaning working position with infinite positions in between.
  • the construction and movement of the present embodiment also offers to be applicable in many other situations, where a person needs an elevated seating support for various tasks, which traditionally can only be achieved with different specific chairs.
  • Fig. 1 depicts a schematic side view of the described embodiment of the described office chair construction in accordance with the present invention
  • Fig. 2 depicts an isometric view of the embodiment of the said office chair:
  • Fig. 3 depicts the schematic side view of the anatomic premise which the current embodiment is based on and referring to;
  • Fig. 4 depicts a schematic side view of the common situation of seat structures offered to the marked at present, showing the angles of a generally backward tilted position and a second acute forward tilted position the current embodiment claims to achieve;
  • Fig. 5 depicts an isometric exploded view of the components of the entirety of the adjustable support structure portion (C);
  • Fig. 6 depicts the hinge arrangement in the apparatus (C) between the transverse pivotal backrest support lever and the transverse pivotal rear lever of the parallelepiped, that controls the reverse synchronized movement of the backrest in relation to the seat pan (D) by means of a dual engaging herringbone gear;
  • Fig. 7 depicts the fundamental schematic function of the adaptive structure of the parallelepiped used in the current invention.
  • Fig. 8 depicts the side view of the assembly (C) of the exploded support structure as in Fig. 7 and its members referring to the assumptions of Fig. 4 in the known horizontal position;
  • Fig. 9 depicts a side view assembly of the support structure and its members and proportions as shown in Fig. 10, but raised to the acute forward tilted position and describes the alignment with the fulcrum reference point of the knee joint;
  • Fig. 10 depicts a side view assembly of the support structure and its members and proportions as shown in Fig 10, but lowered to a reclined rearward position and with a continuous fulcrum reference point in the knee joint;
  • Fig. 11 depicts the means of adjustment of the backrest support lever F or backbone, by which the height of the backrest and the seat depth are adjustable in relation to the seat pan (D);
  • Fig. 12 depicts the flexible foam insert arrangement of the seat (D) to form an articulated contour through different densities in the foam
  • Fig. 13 depicts the arrangement of separating two different densities in the flexible seat foam and its insertion and fixing
  • Fig. 14 depicts a side view of a human body seated upon the contoured seat foam insert in the elevated forward tilting position
  • Fig. 15 depicts a side view of the preferred embodiment of the apparatus as an assembly of portions in a lower reclined position
  • Fig. 16 depicts a side view of the preferred embodiment of the apparatus as an assembly of portions in a traditional ninety degree angle seat position
  • Fig. 17 depicts a side view of the preferred embodiment of the apparatus as an assembly of portions in an acute forward tilted position
  • Fig. 1 generally depicts an office chair and schematically represents a possible embodiment of the invention.
  • the seating assembly generally comprises eight elements: a five-prong base assembly (demoted A), a support column assembly (demoted B), a support structure in the form of a mechanism (demoted C), a seat pan (demoted D), a support structure in the form of an armrest (demoted E), a support structure in the form of a backbone (demoted F), a backrest support structure (demoted G), a support structure in the form of a headrest (demoted H),
  • the base A is structured as a classic 5-prong rolling leg frame which acts as a support mount for structure B, which comprises a standpipe with a nylon bush insert, which carries a telescopic gas cylinder, which can be adjusted in height in order to adapt to the specific seat height of each user for such a seat support structure.
  • mechanism D and seat pan C which form the heart of this current invention and support comprise a plurality of portions, which will be described in detail below.
  • Fig. 3 depicts the biomechanical background and explanation for the function of the current invention and describe part of the human skeleton, in particular the arrangement of the bone structure and movement around the hip joint.
  • Fig. 3 shows the relative angles between the pelvis and thigh bone when sitting on a horizontal seating surface and when tilted up and forward by 18 degrees or more over the horizontal. It is by now a scientific established fact, that the maximum angle of lateral movement between hip bone and pelvis is 60 degrees, while the remaining 30 degrees take place in the lumbar part of the spine directly above the pelvis, the result of which is a conversion of the natural spine curve (lordosis) into the opposite curve (kyphosis).
  • Fig. 4 depicts firstly the seating configuration and the corresponding torso-to-thigh angles of a traditional seating support structure in a traditional horizontal position and illustrates the effect of the limitation of seat support structures most commonly present in the market
  • 4.a represents the pivotal location of the hip joint, the knee joint in 4.b and the pivotal point of the foot in joint 4.c, which remains stationary through the whole movement and depicts secondly one of the claims and the aim of the current invention to modify the seating support structure in such a way, that a torso-to-thigh angle of 115 degrees or more can be maintained throughout the entire elevation movement from the utmost lower back recline to the upper most forward incline.
  • Fig. 5 depicts an exploded isometric view of all components comprising the apparatus assembly of portion (C) in Fig. 1.
  • transverse mounted pivotal lever 7 which engages with the rear transverse mounted pivotal lever 4 of the parallelepiped by means of a herringbone gear incorporated on the surface of both the backrest support lever 7 and the rear pivotal lever of the parallelepiped 4, which forces a synchronized compulsory reverse movement of the backrest support with an over-proportional change of angle relative to the seat pan (see Fig. 8).
  • Fig. 6 depicts an illustration of the interconnecting herring bone gear between the lateral pivotal backrest support lever 7 and the lateral pivotal rear lever of the parallelepiped 4.
  • Fig. 7 depicts the underlying concept of the articulation of the movement of the seat pan from lower reclining to higher forward tilting by employing a parallelepiped to simulate a rotation of the seat pan around the imaginary fulcrum of the knee joint.
  • Fig. 8 In this embodiment of the invention, the various portions of the support structure (C) are connected via hinge or pivot means, to define the support structure C in a horizontal position, whereas the uplifting force 3 is at its lower hinge point pivotally hinged to the bearing structure 2 in point 3.1 and at its upper end to the transverse pivotal rear lever 4 in pivot point 3.2.
  • the upper forward pivotal hinged lever 5 is at its lower end hinged pivotal to the front of bearing base 2 in point 5.1 and at its upper end to the seat pan support plate 6 in point 5.2.
  • the lower backward pivotal hinged lever 4 is at its lower point pivotal hinged to the bearing base structure 2 in point 4.1 and at its upper pivotal point to the seat pan support plate 6 in point 4.2.
  • Fig. 9 shows the support structure C moved into a desired second forward inclined position and how it enables the subject supported by the structure to be moved from a relative lower backward reclining position to an acute elevated forward seated position (and vice versa), or to any position along a continuum between those two extremities.
  • the range of movement between the first and any desired second position is controlled and limited solely by the extend of movement permissible of portion 3.
  • Fig. 10 depicts the preferred embodiment of the apparatus assembly of portion C and described in Fig. 8 in its rearward reclined status.
  • Fig. 11 shows the connecting bracket between the adaptive support structure C and the backrest support structure F with oval slots to allow ergonomic alignment according to the proportions of a seated person both lateral as vertical, by means of a screw type locking handle.
  • Fig. 12 and 13 describe the arrangement and fixing of two separate portions of flexible foam, whereby the overall seat foam density is higher than the inserted soft foam pad at the rear of the seat to allow the formation of a cavity or a bowl, which retains a seated persons buttocks in said bowl, based on the anatomy of the human body as shown in Fig. 14.
  • Fig. 14 depicts a side view of the assembly with a human body placed on the inclined forward tilting seat pan D and the contour formed under the upper thigh with the protruding buttock at the rear.
  • Fig. 15 depicts a side view as in Fig. 14, with a person sitting on it in reclining posture.
  • Fig. 16 depicts a side view as in Fig. 14, with a person sitting on the horizontal seat.
  • Fig. 17 depicts a side view as in Fig.14 with the desired forward seat inclination.
  • the present embodiment applies to a seating support structure in the form of an office chair, which allows a user to sit upright on a forward tilting elevated seat support, which tilts the pelvis forward, opens the body angle between the thigh and the upper body and allows the user to maintain a natural curved spine while sitting. Because of the elevated forward tilting seat, it provides an easy- sitting and easy-rising motion, while the feet remain squarely placed on the floor. This encourages more frequent motion and supports a more dynamic seating in particular, when combined with a height adjustable table, and aims to solve one of the most prominent medical conditions of lower back pain.

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  • Health & Medical Sciences (AREA)
  • Dentistry (AREA)
  • General Health & Medical Sciences (AREA)
  • Chairs For Special Purposes, Such As Reclining Chairs (AREA)

Abstract

L'invention concerne un appareil de support de siège. L'appareil de support de siège est utilisé en tant que mécanisme de support de siège, le siège (D) étant déplacé de manière pivotante d'une position d'assise inclinée vers l'avant plus élevée à une position d'assise inclinée vers l'arrière inférieure sur un axe de pivotement transversal avec un point d'appui représentant l'articulation du genou (4.b). L'appareil comprend deux paires de leviers articulés à pivotement transversal, qui forment un parallélogramme entre la base de palier (2) et une structure de support de siège (6). La structure de support de siège (6) forme un parallélépipède avec deux côtés opposés inégaux, la partie (4) étant plus longue que la partie (5), de telle sorte que la rotation simule la rotation de la cuisse avec le point d'appui dans l'articulation de genou (4.b) et supporte ainsi uniformément la longueur de la cuisse par l'intermédiaire de son mouvement entier. Un troisième levier pivotant transversal (7) est en prise au moyen d'un engrenage de surface hélicoïdale (7.2) avec le levier de pivot arrière (4) dans un point (4.4) pour forcer un mouvement synchronisé inverse du dossier lorsqu'il s'incline vers le haut, ouvrant ainsi l'angle entre la cuisse et le corps supérieur.
PCT/TH2024/000002 2023-05-02 2024-01-18 Structure de support de siège inclinable à pivots multiples Ceased WO2024253601A1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202480029856.3A CN121099936A (zh) 2023-05-02 2024-01-18 多枢轴倾斜座椅支撑结构

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
THPCT/TH2023/000011 2023-05-02
PCT/TH2023/000011 WO2024228680A1 (fr) 2023-05-02 2023-05-02 Structure de support de siège inclinable à pivots multiples

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WO2024253601A1 true WO2024253601A1 (fr) 2024-12-12
WO2024253601A4 WO2024253601A4 (fr) 2025-09-18

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PCT/TH2023/000011 Ceased WO2024228680A1 (fr) 2023-05-02 2023-05-02 Structure de support de siège inclinable à pivots multiples
PCT/TH2024/000002 Ceased WO2024253601A1 (fr) 2023-05-02 2024-01-18 Structure de support de siège inclinable à pivots multiples

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PCT/TH2023/000011 Ceased WO2024228680A1 (fr) 2023-05-02 2023-05-02 Structure de support de siège inclinable à pivots multiples

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CN (1) CN121099936A (fr)
WO (2) WO2024228680A1 (fr)

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0793929A1 (fr) * 1996-03-04 1997-09-10 Rudimec B.V. Chaise de bureau réglable
WO2001000061A1 (fr) * 1999-06-28 2001-01-04 Studio Innova Inc. Fond de siege a angle ouvert perfectionne pour siege
US20010006300A1 (en) * 1999-12-22 2001-07-05 Mitsuo Hayashi Chair assisting rising movements
US20110101748A1 (en) * 2009-10-13 2011-05-05 Goetz Mark W Ergonomic Adjustable Chair Mechanisms
US8272692B1 (en) * 2009-10-26 2012-09-25 Epperson Ronald B Office chair having tiltable seat and back
CN110313743A (zh) * 2018-03-28 2019-10-11 霍沃思公司 椅子椅座的向前倾斜组件
CN115151167A (zh) * 2020-02-21 2022-10-04 艾特龙有限责任公司 椅子

Family Cites Families (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE19823632C1 (de) * 1998-05-27 1999-09-30 Roeder Peter Stuhl, insbesondere Bürostuhl
GB0609315D0 (en) * 2006-05-11 2006-06-21 Technicon Internat Man Service Improved seat
ITTO20070398A1 (it) * 2007-06-06 2008-12-07 Malenotti S R L "sedia con schienale oscillante"
KR101009490B1 (ko) * 2010-04-28 2011-01-21 주식회사 토치 앉는 위치가 조절되는 좌판부의 이동구조를 갖는 의자
WO2014021796A1 (fr) * 2012-08-03 2014-02-06 Kummer Klaus Juergen Structure de support réglable
GB2553750B (en) * 2016-06-28 2019-06-05 Posturite Ltd Seat tilting mechanism
WO2019156641A1 (fr) * 2018-02-07 2019-08-15 CHAICHANA, Suladda Structure de support de siège réglable

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0793929A1 (fr) * 1996-03-04 1997-09-10 Rudimec B.V. Chaise de bureau réglable
WO2001000061A1 (fr) * 1999-06-28 2001-01-04 Studio Innova Inc. Fond de siege a angle ouvert perfectionne pour siege
US20010006300A1 (en) * 1999-12-22 2001-07-05 Mitsuo Hayashi Chair assisting rising movements
US20110101748A1 (en) * 2009-10-13 2011-05-05 Goetz Mark W Ergonomic Adjustable Chair Mechanisms
US8272692B1 (en) * 2009-10-26 2012-09-25 Epperson Ronald B Office chair having tiltable seat and back
CN110313743A (zh) * 2018-03-28 2019-10-11 霍沃思公司 椅子椅座的向前倾斜组件
CN115151167A (zh) * 2020-02-21 2022-10-04 艾特龙有限责任公司 椅子

Also Published As

Publication number Publication date
WO2024253601A4 (fr) 2025-09-18
CN121099936A (zh) 2025-12-09
WO2024228680A1 (fr) 2024-11-07

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