Pivoting support mechanism for chairs and other structures

Abstract

A chair for supporting a seat occupant that includes a pivoting support to create pivoting movement about multiple movement axes to create freedom of movement of the chair. The pivoting support includes a first support link and a second support link that each have first ends rotatable about a first movement axis. A third support link and fourth support link are each connected to one of the first and second support links and are rotatable about second and third movement axes. The second end of each of the third and fourth support links are rotatable about fourth and fifth movement axes. The pivoting support includes a locking mechanism to hold the chair in place when the seat occupant is not present. The pivoting support also limits the movement of the support links relative to each other to define ends of movement for the chair.

Description

CROSS REFERENCE TO RELATED APPLICATION

[0001] The present application is based on and claims priority to U.S. Provisional Application Ser. No. 63 / 781,001, filed on Mar. 31, 2025, the disclosure of which is incorporated herein by reference.BACKGROUND

[0002] The present disclosure generally relates to a chair or other similar support structure for supporting a user. More specifically, the present disclosure relates to a pivoting support that supports a seat and allows the user to move along a virtually unlimited number of movement paths while seated.

[0003] Decades of research studies indicate that a repetitive rocking motion has a positive effect on people of all ages. The rocking motion has been shown to benefit those suffering from various ailments to the extent that some have adopted the label “Rocking Chair Therapy”.

[0004] In one 1998 study of nursing home residents, University of Rochester School of Nursing, researchers found that patients with Alzheimer's disease who rock for 1-2 hour per day in a chair “demonstrated significant improvements in depression, anxiety, and balance and a decrease in pain medication usage.” In another study, researchers demonstrated rocking improved circulation to the brain. Some physiotherapists claim rocking may produce a sedative effect and aid in pain management, easing lower back pain. The potential benefits extend to the relief of psychological symptoms of anxiety and depression.

[0005] However, rocking back and forth on curved slats bearing against a rigid surface causes a jerking motion—thereby detracting from the rocking experience.

[0006] A variety of apparatus incorporate swinging, gliding, rocking or bouncing motion to provide users—from infant to adult—with relaxation, comfort, improved circulation and other benefits. In a sitting, prone, or upright position, current designs for infants and baby swings commonly provide either front-to-back or side-to-side motion.

[0007] In one common swing configuration, a seat or cradle is attached and suspended above the ground from the top of a frame. To take advantage of a full range of swinging motion and benefit from a longer smoother swing, the center / pivot point of the frame must be positioned a substantial distance above the seated user. The overall frame must thus be made correspondingly larger to provide stable support. Current manufacturers offer small-medium-large designs. Taller swings may be top heavy, thus presenting safety concerns. Furthermore, the motor and lines of attachment residing above the user may serve to block visibility of, for example, an infant in distress, and limit immediate access when necessary.

[0008] In another common configuration, a cradle or seat is provided on a frame and attached on the sides thereof to enable front-to-back and / or side-to-side motion in a glider design. In contrast to attaching a seat or cradle from above the seated user, the gliding design configurations limit motion to short, front-to-back or side-to-side. While the seated user is not obstructed from view or accessibility, structural parts of the frame may trap or pinch a body part of the user.

[0009] The inventors of the present disclosure recognized the benefits and desire for a chair or other support structure that allows the user unencumbered movement in an unlimited number of directions to replicate the feeling of swinging from an overhead support. In addition, the inventors have recognized the need to provide stability for such a chair during the initial seating of the user and again when the user desires to no longer be seated.SUMMARY

[0010] The present disclosure relates to a chair or other human support that is supported by a pivoting support. In one embodiment, the pivoting support includes a “W” linkage that is defined by a first pair of support links and a second pair of support links. The first pair of support links are rotatable about each other at first ends of the first pair of support links to define a first movement axis. The first and second pair of support links are rotatable relative to each other at second and third movement axes that are located between the second end of one of the first pair of support links and the first end of one of the second pair of support links. The second end of each of the second pair of support links are mounted to a seat pan and are rotatable about fourth and fifth movement axes. The five separate movement axes are all spaced from each other, are non-parallel and converge above the chair.

[0011] The “W” configuration of the support links creates a balanced arrangement that allows the chair to return to a neutral state when unoccupied and to remain compact under the seat of the chair.

[0012] The present disclosure includes mechanisms to prevent the support links from traveling over center and thus inverting the pivoting support. These limits exist between the pair of lower support links and between the lower support links and the upper support links.

[0013] The present disclosure further includes a specific bearing arrangement to create the smooth movement between the support links during movement by the seat occupant. The bearing arrangement can be located at each of the connections along the five movement axes.

[0014] The present disclosure further includes a locking mechanism that automatically locks the chair motion when the chair is unoccupied. This locking feature allows easier entry into the chair by the seat occupant and easier mobility for an unoccupied chair.

[0015] The locking mechanism can include time-release mechanism that slows the unlocking of the chair motion when the seat occupant initially sits in the chair. Such feature is particularly desirable in a lounge chair configuration. The locking mechanism can further include a manual activation device such that the seat occupant can lock and unlock the movement of the chair when the occupant is seated in the chair.

[0016] In accordance with an aspect of the present disclosure, a chair is provided for use by a seat occupant that includes a seat and a base positioned below the seat. A pivoting support is positioned between the base and the seat to allow the seat to move relative to the base about a plurality of movement axes. The pivoting support returns the seat to a home position when the seat occupant is not present. The pivoting support includes a first support link and a second support link each extending between a first end and a second end. The first ends of the first and second support links are rotatably mounted to each other to define a first movement axis. The pivoting support further includes a third support link and a fourth support link each extending between a first end and a second end, wherein the first end of the third support link is rotatably mounted to the second end of the first support link to define a second movement axis and the first end of the fourth support link is rotatably mounted to the second end of the second support link to define a third movement axis. The second end of the third support link is rotatably mounted to the seat to define a fourth movement axis and the second end of the fourth support link is rotatably mounted to the seat to define a fifth movement axis.

[0017] In another aspect and in accordance with any preceding aspect, the pivot support further includes a locking mechanism that is movable between a locked condition and a released condition, wherein the locking mechanism prevents the rotational movement of the third and fourth support links about the fourth and fifth movement axis when in the locked condition.

[0018] In another aspect and in accordance with any preceding aspect, the locking mechanism includes a pressure pad located within the seat, wherein the pressure pad is engaged by the seat occupant when the occupant is seated on the seat.

[0019] In another aspect and in accordance with any preceding aspect, the locking mechanism further includes a manual release paddle that is selectively movable by the seat occupant, wherein the movement of the chair is unlocked by a combination of the pressure pad and the manual release paddle. When the pressure pad is engaged by the seat occupant, the seat occupant is able to toggle between the locked and unlocked conditions for the movement of the seat.

[0020] In another aspect and in accordance with any preceding aspect, the locking mechanism is moved to the released condition upon movement of the pressure pad by the seat occupant.

[0021] In another aspect and in accordance with any preceding aspect, the locking mechanism includes a movement damper that delays the movement of the locking mechanism from the locked condition to the released condition upon movement of the pressure pad.

[0022] In another aspect and in accordance with any preceding aspect, the base comprises a height adjuster including a cylinder that is selectively actuated to adjust the height of the seat and a release handle pivotably mounted to one of the first or second support links, the release handle having a first end in contact with the height adjustment cylinder and a second end spaced from the first or second support link. The movement of the second end of the release handle toward the first or second support link engages the height adjuster and adjusts the position of the cylinder.

[0023] In another aspect and in accordance with any preceding aspect, the first end of the first support link includes a movement channel extending between a first wall and a second wall and the first end of the second support link includes a block sized to be movably received in the movement channel, wherein the block contacts the first and second walls to limit the rotational movement along the first movement axis.

[0024] In another aspect and in accordance with any preceding aspect, a resilient bumper is provided on the block, wherein the resilient bumper contacts the first and second walls to dampen the contact between the block and the first and second walls.

[0025] In another aspect and in accordance with any preceding aspect, the second end of both the first support link and the second end of the second support link include a movement grove that receives a pin formed on the first end of each of the third and fourth support links, wherein the interaction between the pin and the movement grove limits the rotation about the second and third movement axes.

[0026] In another aspect and in accordance with any preceding aspect, the first, second, third, fourth and fifth movement axes are non-parallel and intersect with each other.

[0027] In another aspect and in accordance with any preceding aspect, the second end of each of the third and fourth support links is connected to a stub shaft that is rotatable relative to the seat, wherein an upper end of the stub shaft includes a fan plate that rotates with the stub shaft.

[0028] In another aspect and in accordance with any preceding aspect, the rotation of the fan plate is prevented by the locking mechanism when the locking mechanism is in the locked condition.

[0029] In another aspect and in accordance with any preceding aspect, the rotation of the fan plate is prevented when the pressure pad is not engaged by the user.

[0030] In another aspect, the combination of the first and second support links and the third and fourth support links have a W configuration in the home position without the seat occupant present on the seat.

[0031] In another embodiment of the present disclosure, a pivoting support is provided for use with a chair having a seat and a base. The pivoting support includes a first support link and a second support link each extending between a first end and a second end, wherein the first ends of the first and second support links are rotatably mounted to the base and are rotatable relative to each other to define a first movement axis. The pivoting support further includes a third support link and a fourth support link each extending between a first end and a second end, wherein the first end of the third support link is rotatably mounted to the second end of the first support link to define a second movement axis and the first end of the fourth support link is rotatably mounted to the second end of the second support link to define a third movement axis. The second end of the third support link is configured to be rotatably mounted to the seat to define a fourth movement axis and the second end of the fourth support link is configured to be rotatably mounted to the seat to define a fifth movement axis. Further, the pivoting support allows the seat to move relative to the base about the first, second, third, fourth and fifth movement axes.

[0032] In another aspect and in accordance with any preceding aspect, the pivoting support includes a locking mechanism that is movable between a locked condition and a released condition, wherein the locking mechanism prevents the rotational movement of the third and fourth support links relative to the seat when in the locked condition.

[0033] In another aspect and in accordance with any preceding aspect, the locking mechanism includes a pressure pad that is engaged by the seat occupant when the occupant is seated on the seat.

[0034] In another aspect and in accordance with any preceding aspect, the locking mechanism further includes a manual release member that is selectively movable by the seat occupant, wherein the movement of the chair is unlocked and locked by a combination of the pressure pad and the manual release member.

[0035] In another aspect and in accordance with any preceding aspect, the locking mechanism is moved to the released condition upon movement of the pressure pad by the seat occupant.

[0036] In another aspect and in accordance with any preceding aspect, the locking mechanism includes a movement damper that delays the movement of the locking mechanism from the locked condition to the released condition upon movement of the pressure pad.

[0037] In another aspect and in accordance with any preceding aspect, the combination of the first and second support links and the third and fourth support links are configured to return the seat to a home position when a seat occupant is not present. The combination of the support links have a W configuration in the home position without the seat occupant present on the seat.

[0038] Various other features, objects and advantages of the invention will be made apparent from the following description taken together with the drawings.BRIEF DESCRIPTION OF THE DRAWINGS

[0039] The drawings illustrate the best mode presently contemplated of carrying out the disclosure. In the drawings:

[0040] FIG. 1 is a front, top perspective view of first embodiment of a chair including the pivoting support of the present disclosure;

[0041] FIG. 2 is a front, bottom perspective view of the chair and pivoting support of the present disclosure;

[0042] FIG. 3 is a bottom, perspective partially exploded view of the chair and pivoting support;

[0043] FIG. 4 is a bottom view taken along line 4-4 of FIG. 2;

[0044] FIGS. 5A-5C are front views showing the movement of the pivoting support between various positions showing the front-to-back movement of the seat;

[0045] FIGS. 6A-6C are side views showing the movement of the pivoting support between various positions when supporting the seat of the chair;

[0046] FIGS. 7A-7C are front views showing the movement of the pivoting support between various positions showing the side-to-side movement of the seat;

[0047] FIG. 8 is an exploded view showing the connection between the third and fourth support links and the pivot limiting interaction between the two pair of support links;

[0048] FIG. 9 is an exploded view showing the interaction between the first and second support links and the support link that includes the height adjustment release handle;

[0049] FIG. 10 is a top view showing the bearing arrangement between one of the third or fourth support links and one of the first or second support links;

[0050] FIG. 11 is an exploded view showing the bearing arrangement and connection between one of the third or fourth support links and one of the first or second lower support links;

[0051] FIG. 12 is a section view showing the movement limiting stops between the first and second support links and between each of the first and second support links and the third and fourth support links;

[0052] FIG. 13 is a partial section view showing the pivoting connections between the first and second support links and between the first and second support links and the third and fourth support links;

[0053] FIGS. 14A-14C are magnified top views showing the movement of the seat slide release paddle to permit the front-to-back movement of the seat;

[0054] FIG. 15A is a top view of the seat pan with the seat cushion removed and a seat pressure pad in the non-engaged position in which movement of the chair is locked;

[0055] FIG. 15B is a top view of the seat pan with the seat pressure pad engaged by a seated occupant;

[0056] FIG. 15C is top view showing depression of the movement release paddle, which releases the movement of the chair when the seat occupant is present;

[0057] FIG. 15D is a top view showing the movement of the chair when the seat pressure pad and the movement release paddle are engaged;

[0058] FIG. 16A is a section view showing the seat pressure pad in the non-engaged, locking position;

[0059] FIG. 16B is a section view showing the seat pressure pad in the engaged, release position and with the movement release paddle not yet depressed;

[0060] FIG. 16C is a section view showing the seat pressure pad in the engaged, release position and with the movement release paddle depressed;

[0061] FIG. 17A is a section view showing the movement release paddle in the non-engaged, locking position;

[0062] FIG. 17B is a section view showing the seat pressure pad in the engaged, release position and with the movement release paddle not yet depressed;

[0063] FIG. 17C is a section view showing the seat pressure pad in the engaged, release position and with the movement release paddle in the depressed position;

[0064] FIG. 18 is a front, top perspective view of a second embodiment of a lounge chair including the pivoting support of the present disclosure;

[0065] FIG. 19 a front, bottom perspective view of the second embodiment of the lounge chair and pivoting support of the present disclosure;

[0066] FIG. 20 is a partial exploded view showing the locking mechanism including the pressure pad that is used to release the movement of the seat upon activation by a user;

[0067] FIG. 21A is a view showing the pressure pad in the locked position to prevent movement of the seat;

[0068] FIG. 21B is view showing the movement of the pressure pad by the user to release the movement of the seat; and

[0069] FIG. 21C is a view showing the delayed release of the movement of the seat.DETAILED DESCRIPTION

[0070] FIG. 1 illustrates a chair 10 constructed in accordance with the present disclosure. In the embodiment shown in FIG. 1, the chair 10 is an office chair, often referred to as a task chair. However, it should be understood that the chair 10 could be a variety of different types of chairs, such as but not limited to the task chair shown in FIG. 1 and the lounge chair shown in FIG. 18. In addition, the chair 10 could be any other type of support structure that supports a user or occupant on a seat or other similar support element. Such alternate support structures could be a stool, bench, ottoman or other similar type of structure. In the embodiments illustrated, the chair 10 includes a seat back but it is contemplated that the chair 10 could be constructed without a seat back while operating within the scope of the present disclosure. In addition, it is contemplated that the chair could include other elements, such as arms, a foot rest, etc.

[0071] The chair 10 shown in FIG. 1 includes the pivoting support 12 constructed in accordance with the present disclosure. The pivoting support 12 creates a balanced motion that is configured to return the chair to a center position when an occupant is not positioned on the seat 14. FIG. 1 illustrates the home, center position that the chair returns to when the seat is not occupied.

[0072] When an occupant is on the seat 14, the pivoting support 12 allows for free-floating movement of the chair 10 along multiple different movement axes to simulate a swinging movement of the chair 10. The pivoting support 2 includes multiple movement axes that are created at the pivoting joints between the structural members of the pivoting support mechanism 12 to provide the balanced motion for the chair 10. The multiple movement axes are not parallel to each other and in the embodiment illustrated are arranged such that the movement axes converge at a location that is above the chair 10. However, it is also contemplated that the movement axes could converge in other locations or could not ever all converge at a single location. The orientation of the multiple movement axes creates the self-centering motion of the chair, as will be described in greater detail below. The self-centering movement of the chair to the home position shown in FIG. 1 is due to the configuration of the structural members and the weight of the chair without the need for any separate biasing members, such as springs.

[0073] In the embodiment shown in FIG. 1, the pivoting support 12 of the task chair is mounted to a seat post 16 that is extendable into and out of a base 18 having a series of support legs 20 that each include a castor wheel 22 to support the base 18 for rolling movement along a floor surface. Although a specific type of base 18 is shown, it should be understood that the pivoting support 12 of the present disclosure could be utilized with any type of base that could be either stationary or include caster wheels 22 to allow for rolling movement of the entire chair 10 along a surface. In other contemplated embodiments, the base 18 could be stationary, such as the ground, a floor mounted support or any other element that receives the seat post 16. In the embodiment shown in FIG. 1, the chair 10 can include a seat back 24 that would allow the user to recline or to support the back of the occupant. In the embodiment shown, only the outer frame of the seat back 24 is illustrated but it should be understood that different material could be mounted to the outer frame, such as a cushion, a nylon mesh or a solid surface. In other embodiments, the seat back 24 could be eliminated depending on the desired configuration of the chair 10. The seat post 16 defines a central, first movement axis 23 for the chair 10. The seat 14 is rotatable about the first movement axis 23 as is well known in the field of task chairs.

[0074] Referring now to FIGS. 2 and 3, the pivoting support 12 is designed to be securely connected to a seat pan 26 that forms part of the seat 14 and supports a cushion 28. The seat pan 26 is a stiff, durable component that can be formed from a variety of materials, such as molded plastic, nylon or metal. The seat pan 26 supports the weight of the seat occupant during use.

[0075] As shown in FIGS. 2-4, the pivoting support 12 includes a pair of lower support links, including a first support link 29 and a second support links 30. The pivoting support mechanism includes a pair of upper support links, including a third support link 31 and a fourth support links 32. The series of lower and upper support links are formed from a metallic material although other materials are contemplated as being within the scope of the present disclosure. The term support link in the present disclosure is meant to describe the embodiment illustrated. However, other shapes and configurations of the support links are contemplated, such as various types of linkages that carry out the functions of the support links described herein. In the embodiment shown, the first and second support links 29 and 30 are located below the third and fourth support links 31 and 32. However, other embodiments are contemplated in which the four support links exist in generally the same plane or where the first and second support links 29, 30 are located above the third and fourth support links 31 and 32. The configuration shown in the illustrated embodiment has been found to be the most desirable but is not meant to illustrate the only contemplated configuration.

[0076] The first and second support links 29, 30 are pivotally connected to each other and are positioned slightly above a support coupling 34. The first and second support links 31, 32 are each rotatably connected to the third and fourth support links 29, 30 which in turn are each rotatably connected to one of a pair of barrels 36 that are connected to the bottom surface of the seat pan 26. The pivoting support 12 defines a total of five movement axes that are not parallel to each other and converge at a location above the chair 10. The multiple movement axes allow the pivoting support 12 to create a free-floating pivoting movement of the entire chair 10 when an occupant is on the seat 14.

[0077] As can be seen in FIGS. 2 and 3, the first and second support links 29, 30 each extend slightly upward from the support coupling 34. The third and fourth support links 31, 32 are each positioned above the first and second support links 29, 30 and extend slightly upward to be received by the barrels 36 mounted to or integrally formed with the seat pan 26. This vertical configuration of the support links helps to define the home position for the seat 14, which is shown in FIGS. 1-4. As can be understood, the physical configuration and orientation of the support links returns the seat 14 to the home position when the seat occupant is not present. In this manner, the seat 14 returns to this home position when the seat occupant leaves the seat, such as by standing up from a seated position. When in the home position, the seat is more readily accessible by the next seat occupant.

[0078] As shown in the bottom view of FIG. 4, when the pivoting support is in the home, resting position, the connections between the first and second support links 29, 30 and the third and fourth support links 31, 32 creates a “W” linkage configuration when viewed from above that allows for balanced motion that returns the seat to a centered, home position when an occupant is not present. The four separate support links 29, 30, 31 and 32 are arranged in a symmetrical fashion along the central, first movement axis 23 of the seat that passes through the seat post 16, which in turn is received by the support coupling 34. When an occupant is present in the chair 10, the pivoting support mechanism moves away from the “W” linkage configuration but the pivoting support mechanism returns to this home position and “W” configuration when the seat occupant leaves the chair 10.

[0079] Referring now to the views of FIGS. 2-4, the first support link 29 has a longitudinal length that extends from a first end 37 to a second end 38. Likewise, the second support link 30 includes a similar first end 39 and a second end 40. The pair of first ends 37, 39 of the first and second support links 29, 30 are designed to be rotatably connected to each other such that the first and second support links 29, 30 are rotatable about the first movement axis 23 and the support coupling 34. As shown in FIGS. 2 and 3, the third support link 31 includes a first end 41 and a second end 42 while the fourth support link 32 includes a similar first end 43 and a second end 44.

[0080] As shown in these Figures, the first end 41 of the third support link 31 is positioned above and is rotatably mounted to the second end 38 of the first support link 29 while the first end 43 of the fourth support link 32 is positioned above and is rotatably mounted to the second end 40 of the second support link 40. The pivoting connection between the first and second support links 29, 30 and the third and fourth support links 31, 32 define the second and third movement axes 45, 46 that are best shown in FIG. 5A. The second and third movement axes 45, 46 help create the pivoting movement of the entire chair.

[0081] As can best be understood in FIG. 5A, the chair 10 of the present disclosure includes a fourth movement axis 47 and a fifth movement axis 48 that are defined by the rotating connection between the third and fourth support links 31, 32 and the barrels 36 on the seat pan 26, the details of which will be described in greater detail below. As can be understood in this Figure, the five movement axes are not parallel to each other and converge at a location that is located above the chair 10. The five individual movement axes create the free-flowing and unrestrained movement of the seat 14 when a seat occupant is present.

[0082] Referring back to FIG. 3, the second ends 42, 44 of each of the pair of third and fourth support links 30, 32 are received within one of a pair of barrels 36 that are each securely connected to the bottom surface 50 of the seat pan 26. The barrels 36 are located near the side edges of the seat pan 26 and could be either integrally formed with the seat pan 26 or can be securely connected to the seat pan 26 utilizing various different types of mounting techniques. The rotating connection between the second ends 42, 44 of the third and fourth support links 31, 32 and the barrels 36 create the fourth and fifth movement axes 47, 48 that are shown in FIG. 5A. As indicated above, the five moving axes created by the pivoting connections of the upper and lower support links as well as the movement connection between the support coupling 34 and the pair of barrels 36 create the multiple axes of movement of the chair 10.

[0083] FIGS. 5A-5C, as well as FIGS. 6A-6C illustrate some of the almost unlimited number of positions that the seat of the chair can move into as a result of the free-floating movement of the chair created by the relative pivoting movement of the third and fourth support links 31, 32 and the first and second support links 29, 30. The views in these images are meant for illustration purposes only and are not meant to define the ranges of motion of the support links.

[0084] FIGS. 5A and 6A illustrate the relative movement between the first support link 29 and the second support link 30 such that the pair of links 29, 30 are oriented at a midpoint between the possible rotation between the first and second support links 29, 30. In this position, each of the third and fourth support links 31, 32 are rotated such that the respective support links 31, 32 extends toward the rear of the seat 14.

[0085] In the orientation shown in FIGS. 5B and 6B, the first and second support links 29, 30 are pivoted toward the front of the seat such that the second ends 38, 40 are positioned close to each other. As can be seen in FIG. 6B, in this orientation, the third and fourth support links 31, 32 extend at nearly a 90° angle relative to the first and second support links, which causes the elevation of the front edge 52 of the seat 14 relative to the position shown in FIG. 6A.

[0086] FIGS. 5C and 6C show an orientation in which the first and second support links 29, 30 extend at a maximum rotational angle relative to each other. In this orientation, each of the third and fourth support links 31, 32 extend away from the respective first or second support link toward the rear of the seat 14. In this position, the front edge 52 of the seat 14 is angled more downward as compared to the orientation shown in FIGS. 6A and 6B.

[0087] While FIGS. 6A-6C show the downward and upward movement of the front edge 52 of the seat 14, FIGS. 7A-7C show the side-to-side movement of the seat as a result of the rotation between the four support links of the pivoting support mechanism. As can be understood in FIG. 7A, when the chair 10 and pivoting support mechanism 12 are in the home position, the right side 51 and the left side 53 of the seat are level with each other. FIG. 7B illustrates movement in which the right side 51 is above the left side 53 while FIG. 7C shows the right side 51 below the left side 53.

[0088] Although several possible orientations of the first and second support links 29, 30 and the third and fourth support links 31, 32 are shown in FIGS. 5A-5C, 6A-6C and 7A-7C, it should be understood that the seat is able to independently rotate above the five movement axes to create both forward and rearward tilting of the seat as well as tilting of the seat toward the right and left sides of the seat. The movement along these five non-parallel movement axes create a “floating” feel for the seat occupant when the seat occupant is seated and causing the rotation and movement of the chair.

[0089] FIG. 8 illustrates the movement connection that exists between the third and fourth support links 31, 32 and the first and second support links 29, 30. The movement connection is configured in the illustrated embodiment to include features that limit the amount of rotation of the support links relative to each other. Although one embodiment of the movement limiting feature is shown in the illustrative embodiment, it is contemplated that other configurations and structures could be used to limit and restrict the movement of the third and fourth support links 31, 32 relative to the first and second support links 29, 30. In the illustrated embodiment, the second end 38, 40 of each of the first and second support links 29, 30 includes an upper face surface 54 that includes a recessed movement groove 56 that forms a part of the rotation limiting feature. The upper face surface 54 on each of the first and second support links 29, 30 is not horizontal and is tilted such that the outer edge of the face surface 54 is above the inner edge. The upper face surface 54 is also located above the top face 55. In this manner, each of the first and second support links 29, 30 are angled upward and the second movement axis 45 and the third movement axis 46 are not vertical but are instead angled relative to vertical.

[0090] As shown in FIG. 8 and the section view of FIG. 12, the movement groove 56 formed in each of the face surfaces 54 is curved and is spaced from the second movement axis 45 and the third movement axis 46. The movement groove 56 extends from a first end 58 to a second end 60. The movement groove 56 is sized to receive a tab 62 that extends below a lower edge 64 at the first end 41 of the third support link 31. The tab 62 is also curved at the same radius of curvature as the movement groove 56 and is designed to move along and within the movement groove 56 during the rotating movement of the third support link 31 relative to the first support link 29. The first and second ends 58, 60 of the movement groove 56 limit the degree of rotation of the third support link 31 relative to the first support link 29. Preferably, each of the first and second ends 58, 60 of the movement groove 56 can include a resilient bumper or pad that cushions the contact between the tab 62 and the ends of the movement groove 56. As can be understood in FIG. 7, the fourth support link 32 and the second support link 30 include the same movement groove 56 and tab 62 to limit and thus restrict the movement of the respective support link 31, 32 relative to the mating support link 29, 30.

[0091] Referring now to FIGS. 9 and 12, a similar movement limiting arrangement is included to limit the amount of rotation of the first support link 29 relative to the second support link 30. Although one embodiment of an engagement structure is illustrated, it should be understood that other structures and elements could be included to limit the amount of rotation between the first and second support links 29 and 30. As illustrated in FIG. 9, in the illustrated embodiment of the engagement structure, the second end 40 of the second support link 30 includes a block 66 that extends above a top edge 68. The block 66 is curved and is sized to be received within a movement channel 70 formed in the second end 38 of the first support link 29 that forms the second, mating component of the engagement structure. The movement channel 70 includes a first end 71 and a second end 72 that define the limits for the rotational movement of the first and second support links 29, 30 relative to each other. As can be seen in the section view of FIG. 12, a resilient bumper 73 can be attached to the block 66 on either one or both ends of the block 66 such that contact between the block 66 and either the first or second end 71, 72 of the movement channel 70. As can be understood in FIGS. 9 and 12, the movement channel 70 extends over approximately 180° which allows the relative movement of the first and second support links 29, 30.

[0092] Referring back to FIG. 9, the first support link 29 is formed with a release handle 74. The release handle 74 is pivotally mounted to the first support link 29 and includes an engagement end 76 and an activation tab 78 on the opposite end. The release handle 74 includes a fulcrum point within the receiving channel 79 such that upward movement of the engagement end 76 results in corresponding downward movement of the activation tab 78.

[0093] As can best be seen in the partial section view of FIG. 13, the activation tab 78 contacts the upper flange 80 formed as part of the support coupling 34. The support coupling 34 is formed as part of a height adjuster that includes an activation pin 81 and a height adjustment cylinder 82. When the seat occupant pulls up on the engagement end 76, the support coupling 34 engages the activation pin 81 that in turn is in contact with the height adjustment cylinder 82. In this manner, when the user pulls up on the engagement end 76, the release handle 74 engages the flange 80 and moves the pin 81 downward to allow the compression of height adjustment cylinder 82. If the user is seated on the chair, the height of the chair will then be lowered. To raise the height of the chair, the user again pulls up on the engagement end 76 and pulls slightly upward, thereby allowing the height of the chair to further adjusted. Although the release handle 74 is shown mounted to the first support link 29, it should be understood that the release handle 74 could be located in the other of the support links 29 and 30.

[0094] In the embodiment illustrated, the release handle 74 is used to initiate the height adjustment of the chair. However, other mechanisms could be utilized to engage the height adjustment cylinder 82, such as but not limited to a Bowden cable. In other contemplated embodiments, the height adjuster would respond to an action by the seat occupant to engage the height adjustment cylinder 82 to either raise or lower the seat height.

[0095] FIGS. 10, 11 and 13 illustrate the rotational connection between the second end 38 of the first support link 29 and the first end 41 of the third support link 31. A similar rotational connection is present between the second support link 30 and the fourth support link 32. As shown in the exploded view of FIG. 11, the pivoting connection includes an upper bearing 84 and a lower bearing 85 that are each received on a support shaft 86. An upper pressure plate 88 is secured to the shaft 86 by a connector 90. In this manner, a compression force can be created to help lock the inner race of each of the upper and lower bearings 84, 85 in place. A second connector 91 is received in the bottom end of the shaft 86, as shown in the section view of FIG. 13. The upper and lower bearings 84, 85 allow for the free rotation of the third support link 31 relative to the first support link 29. As indicated previously, the movement groove 56 limits the degree of rotation of the third support link 31.

[0096] Referring now to FIG. 13, the pivoting connection between the first support link 29 and the second support link 30 is shown. As shown in this section view, the first end 37 of the first support link 29 and the first end 39 of the second support link 30 each have a height that is one-half of the total combined height at the rotational connection between the first and second support links. The rotation of the first and second support links 29, 30 relative to each other takes place about a center shaft 92. The center shaft 92 extends through both of the first ends 37, 39 and has a lower end 93 that is sized to receive the height adjustment cylinder 82. The first end 37 of the first support link 29 is rotatably supported about the center shaft 92 by a pair of upper bearings 94 while the first end 39 of the second support link 30 is supported by a similar pair of lower bearings 95. A spacer 99 is located between the pair of upper bearings 94 and another spacer 99 is located between the lower bearings 95. The spacers 99 create the desired spacing between the upper bearings 94 and the lower bearings 95. The spacers 99 are each sized to contact the inner race of each of the bearings 94 and 95.

[0097] The upper and lower bearings 94, 95 allow the respective ends of the first and second support links 29, 30 to rotate about the stationary center shaft 92. The upper end 96 of the center shaft 92 receives a pressure plate 97 that holds the series of upper and lower bearings 94, 95 in compression. The combination of the pressure plate 97 and the spacers 99 help to provide a smooth rotating connection between the links. As described above, the pivoting and rotational movement between the elements of the pivoting support mechanism allows for free-floating movement of the chair when an occupant is within the chair.

[0098] In addition to the pivoting movement of the chair about the five separate movement axes, the chair of the present disclosure also includes a movement feature that allows the seat 14 to move laterally relative to the fixed seat pan toward and away from the seat back 24. The movement of the seat toward and away from the seat back 24 allows the chair 10 to be adjusted and modified depending upon the size of the seated occupant. Although such an adjustment is not unique to task chairs, the unique movement characteristics of the task chair in accordance with the present disclosure resulted in a modification to the adjustment mechanism.

[0099] FIGS. 14A-14C illustrate the seat depth adjustment mechanism of the present disclosure. In the embodiment shown in FIG. 14A, a seat support casting remains stationary while the seat pan 26 and the seat can be moved toward and away from the seat back by the occupant. Such movement adjusts the depth of the seat relative to the seat back. As shown in FIG. 14A, a release paddle 98 extends past the side edge 100 of the seat pan 26. The release paddle 98 can be depressed by a seated occupant to release the seat movement locking mechanism and allow the seat occupant to laterally adjust the position of the seat. The release paddle 98 is accessible by the left hand of a seated occupant, as shown in the view of FIG. 3.

[0100] Referring back to FIG. 14A, the release paddle 98 is coupled to a paddle body 102 that has a series of spaced teeth 104. The spaced teeth 104 are designed to mesh with a series of teeth 106 that are an integral part of the stationary seat casting such that the spaced teeth 104 are movable with the seat relative to the stationary teeth 106. Although not shown in FIG. 14A, both the release paddle 98 and the paddle body 102 are biased into the upright position shown in FIG. 14A by one or more springs. When a seat occupant desires to change the position of the seat relative to the seat back, the occupant depresses the release paddle 98, which moves the release paddle 98 and the paddle body 102 downward, as shown by arrow 109 in FIG. 14B. Upon this downward movement, the series of teeth 104 are moved out of engagement with the teeth 106, as shown in FIG. 14B. When the teeth 104 are in this depressed position, the seat can slide forward as shown by arrow 110.

[0101] Once the seat occupant has moved the seat to the desired position, the release paddle 98 is released and the bias springs return the release paddle 98 to the engaged position, as shown by arrow 111 in FIG. 14C. When released, the teeth 104 again engage the teeth 106 to lock the seat in the desired lateral position. As can be understood in the comparisons of FIGS. 14A-14C, the individual teeth 104 and 106 define discreet positions for the seat.

[0102] In accordance with the present disclosure, the inventors have determined that in some operations and embodiments, it is desirable to provide an automatic locking mechanism that holds the chair in a specific “home” position when an occupant is not seated within the chair. Locking the chair into a defined position allows the seat occupant to more easily become seated on the chair before the chair begins its free-floating movement. In addition, locking the chair into a defined position when the occupant is not present allows the chair to be moved more easily since the chair does not move relative to the base. Various different physical implementations of the locking mechanism are contemplated as being useful with the chair of the present disclosure. Each possible implementation of the locking mechanism carries out the function of holding the chair in the home position before the locking mechanism is released by the seat occupant.

[0103] Referring now to FIGS. 15A-15D, the chair of the first embodiment of the present disclosure includes a locking mechanism 112 that can be used to hold the seat in a stable position until the seat occupant is seated and has released the locking mechanism 112 from a locked condition. In the locked condition, the locking mechanism 112 restricts the movement of the seat about all of the movement axes except for the first movement axis 23. Even when in the locked condition, the chair is able to rotate about the first movement axis 23 in a normal manner as is expected for a task chair. However, the locking mechanism 112 prevents the movement about the four other movement axes previously described.

[0104] Referring now to FIG. 15A, there shown is a top view of the seat pan 26 with the seat cushion removed to illustrate the components of the locking mechanism 112. Generally, the locking mechanism 112 includes a pressure pad 114 and a pair of fan plates 116. Each of the fan plates 116 are securely mounted the stub shaft 86 that is contained in the second end 42, 44 of each of the third and fourth support links 31, 32. Since the fan plate 116 is secured to the stub shaft 86, if the fan plate 116 is prevented from rotating, the fan plate 116 prevents the rotation of the third and fourth support links 31, 32 relative to the seat pan 26. Such rotation lock prevents the movement of the seat. As shown in FIG. 15A, the fan plate 116 includes a locking hole 118 that is sized to receive a locking pin 120. When the locking pin 120 is received within the locking hole 118, the fan plate 116 is prevented from rotating, thereby preventing the rotational movement of each of the third and fourth support links 31, 32. Although a locking hole 118 and locking pin 118 are illustrated, the locking mechanism could include a variety of other alternatives to prevent the rotation of the third and fourth support links 31 and 32. Contemplated embodiments include an open slot and a locking pin, a caliper that can be activated to prevent rotation of the fan plate 116, a ratchet and a pawl or a clamp collar that clamps onto the stub shaft 86. Each of the contemplated embodiments, along with others, are used as part of the locking mechanism to prevent the rotation of the support links until released by the seat occupant.

[0105] As shown in FIG. 16A, the pressure pad 114 is biased into an upper, locked position by a series of bias springs 122. The pressure pad 114 is designed to be received and thus concealed beneath the seat cushion such that the pressure pad 114 is not visible by the seat occupant. The bias springs 122 are selected such that the weight of the seat occupant will be able to compress the bias springs 122 that are positioned to hold the pressure pad 114 in the upper, locked position shown in FIGS. 15A and 16A. When a seat occupant sits in the seat, the weight of the seat occupant overcomes the bias force generated by the bias springs 122 and causes movement of the pressure pad 114 to move in a downward direction, as shown by arrow 121 in FIG. 15B. Although the pressure pad 114 is shown as being part of the locking mechanism 112, other alternatives could be used to react to the weight of user. Contemplated embodiments include a pressure sensor, switch mechanism or similar component that reacts to the presence of the seat occupant.

[0106] FIGS. 16A and 17A show the position of the bias springs 122 that hold the pressure pad in the upper, locked position. In this upward, locked position, an outer flange 124 is in contact with a release pin 126. Thus, in the upwardly biased locked position, as a result of the bias springs 122, the pressure pad 114 prevents the downward movement of the release pin 126. The release pin 126 in turn is coupled to the locking pin 120 which is shown in FIGS. 15A and 16A as being received within the fan plate 116. Thus, prior to the pressure pad 114 being depressed as shown in FIG. 15B, the locking mechanism 112 prevents the free-flowing movement of the seat.

[0107] Referring back to FIG. 15C, when the pressure pad 114 is depressed by the weight of the seat occupant, the seat is still in the locked position to prevent the free-flowing movement of the seat until the seat occupant manually actives the movement release paddle 128. This condition is shown in the views of FIGS. 16B and 17B. In the condition shown, the outer flange 124 of the pressure pad 114 is spaced from the release pin 126, thus allowing for movement of the release pin 126.

[0108] When the seat occupant is seated and desires to unlock the movement of the seat, the seat occupant can then depress a movement release paddle 128, as shown by arrow 129. When the movement release paddle 128 is pressed downward, the movement release paddle 128 moves a wire interlock 130 in a downward direction. The wire interlock 130 is shown in FIG. 16C as being directly coupled to the release pin 126. Since the pressure pad 114 is also depressed at this time, the outer flange 124 has been moved downward, as can be seen in a comparison of FIGS. 16A and 16B. This downward movement of the outer flange 124 creates a movement space, which allows the release pin 126 to move downward, as also can be seen in the comparison of FIGS. 16A and 16C. The downward movement of the release pin 126 moves the locking pin 120 down and out of engagement with the fan plate 116.

[0109] When the locking pin 120 is moved out of engagement with the fan plate 116, the fan plate 116 no longer prevents the rotational movement of the stub shaft 86. The stub shaft 86 is securely mounted to the second end 44 of the respective third or fourth support link 31 or 32. Thus, when the locking pin 120 is released from engagement with the fan plate 116, the stub shaft 86 is able to rotate.

[0110] As shown in FIG. 16B, the stub shaft 86 is received within one of the barrels 36 mounted to the seat pan 26. Upper and lower bearing assemblies 132 and 133 provide rotational support for the stub shaft 86 about the stationary barrel 36.

[0111] Referring back to FIG. 15C, the wire interlock 130 includes a lateral section 134 that extends across the width of the seat pan 26 and is joined to an opposite wire portion 136. The opposite wire portion 136 is joined to an opposite release pin 126, which in turn is coupled to the opposite locking pin 120. Thus, movement of the movement release paddle 128, which is located on only one side of the seat pan, releases both of the fan plates 116 simultaneously. Once the pair of fan plates 116 are released, rotation about the stub shaft 86 is possible, as shown by arrow 137 in FIG. 15B.

[0112] As can be understood by the above description, the locking mechanism 112 of the present disclosure requires both the depression of the pressure pad 114 due to the weight of the seated occupant and the movement of the release paddle 128 in a downward direction. As shown in the view of FIG. 2, the movement release paddle 128 is accessible by the right hand of a seated occupant.

[0113] Once the seated occupant has both become seated and depressed the movement release paddle 128, the seat is able to freely float and move along all five movement axes. Thus, the locking mechanism 112 is biased into a locked position and is only released upon the weight of the seated occupant and the action of the seated occupant to depress the release paddle 128. When the seat occupant stands up and leaves the seat, the bias force created by the bias springs 122 returns the pressure pad 114 to the upper, biased position, which pushed up on the release pin 126, which in turn returns the movement release paddle 128 to the locked position and re-engages the locking pins 120 in the fan plates 116. In this manner, the locking mechanism 112 prevents uncontrolled movement of the seat until the seated occupant is in place and has taken an active step to allow such movement.

[0114] Although the illustrated embodiment of the locking mechanism 112 includes both the pressure pad 114 and the release paddle 128, it is contemplated that either one of these two components could be eliminated such that the locking mechanism 112 would be released upon either the weight of the seat occupant on the pressure pad 114 or upon the manual activation of release paddle 128. In such alternate embodiments, the locking mechanism 112 would still prevent the movement of the seat until the movement is released by the seat occupant.

[0115] FIG. 18 illustrates another embodiment of a chair 138 including the pivoting support 140 that is similar to the pivoting support 12 shown in FIGS. 1-4. In the second embodiment shown in FIG. 18, the chair 138 is a lounge chair, as compared to the task chair of the first embodiment. The pivoting support 140 includes the first and second support links 29, 30 and the third and fourth support links 31 and 32. The four support links are joined to each other in the same way as in the first embodiment to provide the free-floating movement in a manner similar to the task chair 10. However, in the second embodiment of the pivoting support, the angle and length of the first, second, third and fourth support links are slightly different based upon the difference in size between the task chair of FIGS. 1-4 and the lounge chair of FIG. 18. The seat 142 of the lounge chair 138 includes additional padding, higher sides, wider back and other variations that increase the comfort for the seat occupant. The pivoting support 140 includes the same five movement axes that are not parallel to each other and converge above the chair 138. In this manner, the pivoting support 140 creates the floating and freedom of movement as described with respect to the first embodiment.

[0116] The chair 138 includes a base 144 that has stationary feet 146 to stabilize the chair 138. In the embodiment of the chair that is a lounge chair, the first ends 37, 39 of each of the first and second support links 29, 30 are in contact with the top end of the base 144, unlike the first embodiment that includes a seat post and allows for the vertical height adjustment of the chair height.

[0117] In the same manner as the first embodiment previously described, the upper and lower links are pivotable with respect to each other and with respect to both the base 144 and the barrels 36 mounted to the seat pan 148, which is best shown in the bottom view of FIG. 19.

[0118] Most of the components of the second embodiment of the pivoting support 140 are similar or identical to those of the first embodiment and are thus not described again in detail. The lounge chair shown in FIGS. 18-19 is just one other contemplated seat types that could utilize the pivoting support 140 of the present disclosure. Other chairs or other human supports could be used while operating within the scope of the present disclosure. As an illustrative example, a seating member, such as a stool, that does not include a seat back is contemplated as being possible in accordance with the present disclosure.

[0119] Unlike the task chair shown in FIGS. 1-4, the lounge chair 138 of FIGS. 18-19 does not include any height adjuster and also does not include a manual locking release mechanism. However, much like with the first embodiment described previously, the inventors have determined that in some operations and embodiments, it is desirable to provide an automatic locking mechanism that holds the lounge chair 138 in a specific position when an occupant is not seated within the chair. Locking the chair 138 into a defined position allows the seat occupant to more easily become seated on the chair before the chair begins its free-floating movement.

[0120] FIG. 20 is a partially exploded view in which the seat cushion is removed from the seat pan 148 to display the locking mechanism 150 of the second embodiment. The locking mechanism 150 of the second embodiment performs a similar function as the locking mechanism 112 of the previous embodiment. As shown in FIG. 20, the locking mechanism 150 includes a pressure pad 152 that is concealed below the seat cushion and is biased into a locked condition by a series of springs 154. The springs 154 urge the pressure pad 152 upward when a user is not present on the seat. When the pressure pad 152 is in the upward, spring biased locked condition, a pair of activation rods 156 are spring biased outward such that a locking pin 158 formed at the outer end of each of the activation rods is received within a locking groove 160 formed in each of the pair of fan plates 162. The fan plates 162 are similar to the first embodiment and each are securely attached to the top end of a stub shaft 86. Thus, when each of the fan plates 162 are prevented from rotating by the engagement between the locking pin 158 and the locking groove 160, the third and fourth support links 31, 32 are held in position to thus prevent the free-floating movement of the entire seat.

[0121] Although a locking groove 120 and locking pin 158 are illustrated, the locking mechanism 150 could include a variety of other alternatives to prevent the rotation of the third and fourth support links 31 and 32. Contemplated embodiments include an open hole and a locking pin, a caliper that can be activated to prevent rotation of the fan plate 162, a ratchet and a pawl or a clamp collar that clamps onto the stub shaft 86. Each of the contemplated embodiments, along with others, are used as part of the locking mechanism 150 prevent the rotation of the support links until released by the seat occupant.

[0122] Referring back to FIG. 20, the assembled locking mechanism 150 includes a pair of drive rails 168 connected to the pressure pad 152 such that the drive rails 168 move with the pressure pad 152. Each of the drive rails 168 includes an inclined contact ramp 170. When the pressure pad 152 moves downward, the downward movement of the pressure pad 152 causes similar downward movement of each of the pair of drive rails 168. The downward movement of each of the drive rails 168 causes the contact ramp 170 to engage one of a pair of drive blocks 172. The engagement creates a movement force to urge the outward movement of the drive blocks 172 relative to the center line of the seat pan 148. Each of the drive blocks 172 includes a rack 174 having a series of spaced teeth. The rack 174 formed on each of the drive blocks 172 engages a center pinion 176 that has a similar set of teeth. The interaction between the pinion 176 and the racks 174 synchronizes the movement of the pair of drive blocks.

[0123] The pinion 176 is rotatable about a center shaft and includes a dampening mechanism that provides a dampening force to restrict the rotational movement of the pinion 176. Thus, when the pressure pad 152 moves downward, as shown by arrow 178 in FIG. 21B, the dampening force created by the pinion 176 slows the lateral outward movement of the drive block 172. In this manner, the pinion 176 thus creates a delay between the movement of the pressure pad 152 and the movement of the pair of activation rods 156 in the direction shown by the arrows in FIG. 21B. The delay in the movement of the activation rods 156 thus delays the movement of the locking pin 158 out of the locking groove 160 contained in the fan plate 162, as is shown in FIG. 21B. In this manner, when the seat occupant is initially seated on the lounge chair, the lounge chair does not freely move for the time delay. This has been found desirable upon testing with seat occupants who could be otherwise startled by the sudden, free-floating movement.

[0124] Each of the activation rods 156 is biased outward by a spring 180. Thus, each of the drives blocks 172 moves against the spring 180 to retract the activation rods 156 and to release the free movement of the fan plate 162. Once the locking pins 158 are withdrawn from contact with the fan plates 162, rotation about the fourth movement axis 47 and the fifth movement axis 48 is permitted, as shown by the arrows 182.

[0125] When a seat occupant is no longer present, the bias springs 154 urge the pressure pad 152 upward, back into the locked condition. When the seat occupant is no longer present, the weight of the seat and the orientation of the upper and lower support links returns the seat to a “home” position. In this “home” position, each of the fan plates 162 is oriented such that the locking pin 158 is again received within the locking groove 160 through the urging of the springs 180. Thus, when a seat occupant is no longer present, the locking mechanism 150 locks the seat and chair in the home position until the seat occupant is again present.

[0126] In the embodiment illustrated, the damper included as part of the pinion creates approximately a one second delay for when a seat occupant is present until the free-floating movement of the chair 138 is released. Such a delay aids in allowing the occupant to become seated before the seat and chair begin to move.

[0127] In each of the two embodiments described above and shown in the drawing figures, a seat or other type of similar support structure is supported by a pivoting support such that the seat or similar support structure can move along a virtually unlimited number of movement paths. It is contemplated that the pivoting support can be constructed and assembled separately from the seat or other similar support structure. The pivoting support can then be connected to the seat at either the same location where the pivoting support is assembled or the pivoting support can be assembled and shipped to the location where it is operatively connected to the seat to create the entire chair. In such situation, the seat and the pivoting support could be provided by different entities and combined to form the overall chair or similar structure.

[0128] Since the pivoting support includes four separate support links that define the five different movement axes, the method of assembly of the pivoting support mechanism to the seat or other similar support structure requires some type of removable pin or similar element that allows the orientation of the various support links to be manipulated prior to attachment to the seat. In the embodiment illustrated in FIG. 14A, one or both of the stub shafts 86 and fan plates 116 on the two sides of the seat pan 26 are removable to selectively join the pivoting support mechanism to the seat. In the second embodiment illustrated in FIG. 21A, one or both of the stub shafts 164 and the fan plates 162 on the two sides of the seat pan 148 are removable. It is contemplated that other points of connection between the support links could be removably connected to each other to facilitate the assembly of the pivoting support mechanism to the seat or similar support structure.

[0129] The removable assembly method described above allows for the pivoting support and the seat to be separately provided and then assembled at any location. This allows different manufacturers to construct each of the two components of the overall chair or other similar support structure. This is desirable since the designers of the chair or other seating structure can focus on the design elements and then simply incorporate the mechanics of the pivoting support.

[0130] The method of the present disclosure thus can include the step of initially providing a seat or similar support structure. A pivoting support is also provided and the method then couples the pivoting support to the seat or similar support structure to create the overall chair. The pivoting support can be either one of the two pivoting supports shown and described in the preceding description and the drawings Figures. As part of the method of coupling the pivoting support to the seat, one or more removable elements of the pivoting support can removed and then reinstalled to couple the pivoting support to the seat. In this manner, the orientation of the plurality of support links can be adjusted prior to attachment of the pivoting support to the seat.

[0131] This written description uses examples to disclose the invention, including the best mode, and also to enable any person skilled in the art to make and use the invention. The patentable scope of the invention is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they have structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal languages of the claims.

Claims

1. A chair for use by a seat occupant, comprising:a seat;a base; anda pivoting support to allow the seat to move relative to the base about a plurality of movement axes, the pivoting support comprising:a first support link and a second support link each extending between a first end and a second end, wherein the first ends of the first and second support links are rotatably mounted to each other to define a first movement axis;a third support link and a fourth support link each extending between a first end and a second end, wherein the first end of the third support link is rotatably mounted to the second end of the first support link to define a second movement axis and the first end of the fourth support link is rotatably mounted to the second end of the second support link to define a third movement axis,wherein the second end of the third support link is rotatably mounted to the seat to define a fourth movement axis and the second end of the fourth support link is rotatably mounted to the seat to define a fifth movement axis.

2. The chair of claim 1 wherein the pivoting support further includes a locking mechanism that is movable between a locked condition and a released condition, wherein the locking mechanism prevents the rotational movement of the third and fourth support links about the fourth and fifth movement axis when in the locked condition.

3. The chair of claim 2 wherein the locking mechanism includes a pressure pad located within the seat, wherein the pressure pad is engaged by the seat occupant when the seat occupant is seated on the seat.

4. The chair of claim 3 wherein the locking mechanism further includes a manual release paddle that is selectively movable by the seat occupant, wherein the movement of the chair is unlocked by a combination of the pressure pad and the manual release paddle.

5. The chair of claim 3 wherein the locking mechanism is moved to the released condition upon movement of the pressure pad by the seat occupant.

6. The chair of claim 5 wherein the locking mechanism includes a movement damper that delays the movement of the locking mechanism from the locked condition to the released condition upon movement of the pressure pad.

7. The chair of claim 1 wherein the base comprises:a height adjuster that is selectively actuated to adjust the height of the seat; anda release handle pivotably mounted to one of the first or second support links, the release handle having a first end in contact with the height adjuster and a second end spaced from the first or second support link,wherein movement of the second end of the release handle toward the first or second support link engages the height adjuster.

8. The chair of claim 1 wherein the first end of the first support link and the first end of the second support link include engagement structures that are configured to limit the rotational movement along the first movement axis.

9. The chair of claim 8 wherein the engagement structure includes a movement channel formed on one of the first ends that extends between a first wall and a second wall and a block formed on the other first end that is movably received in the movement channel.

10. The chair of claim 9 further comprising a resilient bumper on the block, wherein the resilient bumper contacts the first and second walls to dampen the contact between the block and the first and second walls.

11. The chair of claim 1 wherein the second end of both the first support link and the second end of the second support link and the first end of each of the third and fourth support links include engagement structures that are configured to limit the rotation about the second and third movement axes.

12. The chair of claim 11 wherein the engagement structures include a movement groove that receives a pin such that the interaction between the movement groove and the pin interact to limit the rotation about the second and third movement axes.

13. The chair of claim 1 wherein the first, second, third, fourth and fifth movement axes are non-parallel and intersect with each other.

14. The chair of claim 2 wherein the second end of each of the third and fourth support links is connected to a stub shaft that is rotatable relative to the seat, wherein an upper end of the stub shaft includes a fan plate that rotates with the stub shaft.

15. The chair of claim 14 wherein rotation of the fan plate is prevented by the locking mechanism when the locking mechanism is in the locked condition.

16. The chair of claim 1 wherein the combination of the first and second support links and the third and fourth support links are configured to return the seat to a home position without the seat occupant present on the seat.

17. The chair of claim 16 wherein the first support link, the second support link, the third support link and the fourth support link have a W configuration when viewed from above the chair in the home position without the seat occupant present on the seat.

18. A pivoting support for use with a chair having a seat and a base, the pivoting support comprising:a first support link and a second support link each extending between a first end and a second end, wherein the first ends of the first and second support links are rotatably mounted to the base and are rotatable relative to each other to define a first movement axis;a third support link and a fourth support link each extending between a first end and a second end, wherein the first end of the third support link is rotatably mounted to the second end of the first support link to define a second movement axis and the first end of the fourth support link is rotatably mounted to the second end of the second support link to define a third movement axis,wherein the second end of the third support link is configured to be rotatably mounted to the seat to define a fourth movement axis and the second end of the fourth support link is configured to be rotatably mounted to the seat to define a fifth movement axis,wherein the pivoting support allows the seat to move relative to the base about the first, second, third, fourth and fifth movement axes.

19. The pivoting support of claim 18 further comprising a locking mechanism that is movable between a locked condition and a released condition, wherein the locking mechanism prevents the rotational movement of the third and fourth support links relative to the seat when in the locked condition.

20. The pivoting support of claim 19 wherein the locking mechanism includes a pressure pad that is configured to be engaged by a seat occupant when the seat occupant is seated on the seat.

21. The pivoting support of claim 20 wherein the locking mechanism further includes a manual release member that is selectively movable by the seat occupant, wherein the movement of the chair is unlocked by a combination of the pressure pad and the manual release member.

22. The pivoting support of claim 20 wherein the locking mechanism is moved to the released condition upon movement of the pressure pad by the seat occupant and returns to the locked condition when the seat occupant is no longer seated on the seat.

23. The pivot support of claim 20 wherein the locking mechanism includes a movement damper that delays the movement of the locking mechanism from the locked condition to the released condition upon movement of the pressure pad.

24. The pivot support of claim 18 wherein the combination of the first and second support links and the third and fourth support links are configured to return to a home position without the seat occupant present on the seat and have a W configuration when viewed from above without the seat occupant present on the seat.

Images