Office chair support

Abstract

The utility model discloses an office chair support, office chair support includes: fixed chassis is equipped with drive arrangement on fixed chassis, seat frame, seat frame movably supports the top of fixed chassis, back frame, back frame is located the rear of seat frame, and is hinged with the rear end of seat frame, drive arrangement, install on fixed chassis, its telescopic output and back frame hinged, are used for driving back frame to overturn around its hinge point with seat frame, first connecting rod mechanism, connect between back frame and seat frame, first connecting rod mechanism is configured as when back frame overturns and drives seat frame to rotate relative to fixed chassis, foot support frame, second connecting rod mechanism, connect between back frame and foot support frame, second connecting rod mechanism is configured as when back frame overturns and drives foot support frame to adjust angle relative to seat frame. Utilize single drive source through the overturn of back frame, utilize first connecting rod mechanism and second connecting rod mechanism respectively realize the synchronous linkage adjustment of seat frame and foot support frame.

Description

Technical Field

[0001] This utility model relates to the field of seating technology, and in particular to an office chair bracket. Background Technology

[0002] As people's demands for seating comfort, functionality, and ergonomic fit continue to increase, adjustable seats (such as reclining sofas, electric recliners, medical care chairs, or aviation seats) are widely used in homes, offices, transportation, and rehabilitation care. In existing technologies, many seats already have backrest angle adjustment functions, and some products further integrate seat cushion tilt adjustment, footrest extension, and other functions to meet users' needs for various postures, from sitting to semi-reclining and fully reclining.

[0003] However, most adjustable chairs on the market still suffer from the following shortcomings: Firstly, components such as the backrest, seat cushion, and footrest are typically controlled by separate drive mechanisms, resulting in complex structures, high costs, and requiring multiple operations from the user to complete the overall posture adjustment, making them inconvenient to use. Secondly, even if some products employ linkage mechanisms to achieve coordinated movement of multiple components, their linkage logic is often relatively simple, making it difficult to simultaneously optimize the seat cushion support angle and footrest deployment posture during the backrest flipping process. This leads to uneven pressure distribution on the body, reduced comfort, and even problems such as legs dangling or insufficient lumbar support at certain angles. Furthermore, existing linkage structures often rely on complex gears, slide rails, or electronic control systems, which not only occupy a large space but are also prone to reliability issues due to component wear or control malfunctions. These shortcomings are particularly pronounced in scenarios requiring frequent adjustments or long-term use (such as nursing beds and long-distance transportation seats).

[0004] Therefore, there is an urgent need to provide a seating mechanism that is simple in structure, reliable in operation, and capable of coordinating the backrest, seat, and footrest through a single drive source, so as to simplify operation while improving overall support performance and user experience. Utility Model Content

[0005] This utility model aims to solve at least one of the technical problems existing in the prior art. To this end, this utility model proposes an office chair bracket that uses a single drive source to achieve synchronous and linked adjustment of the angles of the seat frame and footrest through the flipping action of the chair back frame, with the help of a first linkage mechanism and a second linkage mechanism, respectively. The structure is simple and highly reliable.

[0006] An office chair support according to a first aspect of the present invention includes: a fixed base frame; a seat frame movably supported above the fixed base frame; a backrest frame located behind the seat frame and hinged to its rear end; a drive device mounted on the fixed base frame, the drive device having a retractable output end hinged to the backrest frame for driving the backrest frame to rotate around its hinge point with the seat frame via a telescopic movement; a first linkage mechanism connected between the backrest frame and the seat frame, the first linkage mechanism being configured to drive the seat frame to rotate relative to the fixed base frame when the backrest frame rotates; a footrest; and a second linkage mechanism connected between the backrest frame and the footrest, the second linkage mechanism being configured to drive the footrest to adjust its angle relative to the seat frame when the backrest frame rotates.

[0007] Therefore, this utility model provides an innovative office chair support design. Utilizing a single drive source, the backrest frame's flipping motion, along with a first and second linkage mechanism, synchronously adjusts the angles of the seat frame and footrest. This design only requires controlling the backrest frame's movement to coordinate the posture adjustment of the backrest, seat, and footrest. When the backrest frame is flat, the front of the seat rises, and the footrest rises simultaneously, creating a comfortable reclining position. When the backrest frame returns to an upright position, the seat and footrest return to their normal sitting position. The entire system requires no additional drive device, relying entirely on a purely mechanical linkage mechanism to achieve efficient collaboration among multiple components. This not only simplifies the structure and reduces costs but also improves ease of use and ergonomic fit. Furthermore, the use of mechanical linkages instead of a complex electronic control system enhances the product's durability and safety.

[0008] According to some embodiments of the present invention, the first linkage mechanism includes: a first link, one end of which is hinged to the chair back frame; a second link, one end of which is hinged to the other end of the first link, the second link having a support point on its body that is hinged to the fixed base frame, so that the fixed base frame provides rotational support for the second link; the other end of the second link is connected to the front end of the chair seat frame, and the connection is configured to allow the other end of the second link to rotate relative to the chair seat frame and slide along the front-rear direction of the chair seat frame.

[0009] According to some embodiments of the present invention, the lower side of the front end of the chair frame is provided with a sliding groove extending in the front-back direction, and the other end of the second connecting rod is provided with a pin. The pin passes through the sliding groove, so that the second connecting rod slides back and forth along the sliding groove through the pin and rotates relative to the chair frame around the pin.

[0010] According to some embodiments of the present invention, the second linkage mechanism includes: a third linkage, one end of which is hinged to the chair back frame; and a linkage component, which is connected between the third linkage and the footrest, and is hinged to the chair seat frame to obtain a rotation fulcrum; when the chair back frame is flipped, the third linkage drives the linkage component to move around the rotation fulcrum, thereby causing the footrest to adjust its angle relative to the chair seat frame.

[0011] According to some embodiments of this utility model, the linkage component includes: a fourth link, one end of which is hinged to the lower side of the front end of the chair frame, and the fourth link has a hinge point on its body that is hinged to the third link; a fifth link, both ends of which are respectively hinged to the other end of the fourth link and to the footrest; and a sixth link, one end of which is hinged to the lower side of the front end of the chair frame, and the hinge point is located in front of the hinge point between the fourth link and the chair frame, and the other end of the sixth link is hinged to a connection point provided on the fifth link.

[0012] According to some embodiments of the present invention, the linkage component further includes: a seventh link, one end of which is hinged to the connection point on the body of the fourth link located between its two ends, and the other end is hinged to the foot bracket.

[0013] According to some embodiments of this utility model, the linkage assembly includes: an eighth link, one end of which is hinged to the lower side of the front end of the chair frame, and the eighth link has a hinge point on its body that is hinged to the third link; a ninth link, both ends of which are respectively hinged to the other end of the eighth link and to the footrest; a tenth link, one end of which is hinged to the lower side of the front end of the chair frame, and the hinge point is located in front of the hinge point between the eighth link and the chair frame, and the tenth link has a hinge point on its body that is hinged to the ninth link; and an eleventh link, one end of which is hinged to the other end of the tenth link, and the other end of the eleventh link is hinged to the footrest.

[0014] According to some embodiments of the present invention, the chair back frame extends in the vertical direction, and the angle between it and the horizontal plane of the ground is α, satisfying the relationship: 100°<α<160°; and / or the chair seat frame extends in the front-back direction, and the angle between it and the horizontal plane of the ground is β, satisfying the relationship: 0≤β<15°.

[0015] According to some embodiments of the present invention, it further includes: an elastic reset member, one end of which is connected to the first linkage mechanism and the other end of which is connected to the fixed base frame, for providing auxiliary return force during the reset process of the chair back frame.

[0016] An office chair support according to a second aspect embodiment of the present invention includes: a fixed base frame; a seat frame movably supported above the fixed base frame; a backrest frame located behind the seat frame and hinged to the rear end of the seat frame; a drive device mounted on the fixed base frame, the drive device having a retractable output end hinged to the backrest frame for driving the backrest frame to rotate around its hinge point with the seat frame via a telescopic movement; and a first linkage mechanism connecting the backrest frame and the seat frame. Between the chair back frame and the fixed base frame, the first linkage mechanism is hinged to the fixed base frame; the first linkage mechanism is configured to drive the chair seat frame to rotate relative to the fixed base frame when the chair back frame is flipped; a footrest; a second linkage mechanism is connected between the chair back frame and the footrest, and the second linkage mechanism is hinged to the chair seat frame; the second linkage mechanism is configured to move with the rotation of the chair back frame and the chair seat frame when the chair back frame is flipped, so as to drive the footrest to adjust the angle relative to the chair seat frame.

[0017] Additional aspects and advantages of this invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0018] The above and / or additional aspects and advantages of this utility model will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which: Figure 1 This is a first-view structural schematic diagram of the office chair bracket according to an embodiment of the present utility model; Figure 2 This is a structural schematic diagram of the office chair bracket according to an embodiment of the present utility model from a second perspective; Figure 3 This is a structural schematic diagram of the office chair support in the retracted state according to an embodiment of the present utility model; Figure 4 This is a schematic diagram of the office chair support in a flat position according to an embodiment of the present utility model; Figure 5 This is a structural schematic diagram of an office chair bracket according to an embodiment of the present utility model from a third-view perspective. Figure 6 yes Figure 5 Enlarged diagram of point A in the diagram; Figure 7 This is a schematic diagram of the first linkage mechanism in the retracted state according to an embodiment of the present utility model; Figure 8 This is a schematic diagram of the second linkage mechanism in the retracted state according to an embodiment of the present utility model; Figure 9 This is a schematic diagram of the first and second linkage mechanisms in a flattened state according to an embodiment of the present utility model.

[0019] Figure label: 100. Office chair bracket; 1. Fixed base frame; 2. Seat frame; 21. Slide rail; 3. Backrest frame; 4. Drive unit; 41. Output end; 5. First linkage mechanism; 51. First link; 52. Second link; 5201. Support point; 5202. Pin; 6. Footrest; 7. Second linkage mechanism; 71. Third link; 72. Linkage assembly; 7201. Fourth link; 7202. Fifth link; 7203. Sixth link; 7204. Seventh link. Detailed Implementation

[0020] The embodiments of the present invention are described in detail below. The embodiments described with reference to the accompanying drawings are exemplary. The embodiments of the present invention are described in detail below.

[0021] The following is for reference. Figures 1-9 This invention describes an office chair bracket according to an embodiment of the present invention.

[0022] like Figures 1-4 As shown, the office chair support 100 according to the first aspect of the present invention includes: a fixed base frame 1, a seat frame 2, a backrest frame 3, a drive device 4, a first linkage mechanism 5, a footrest 6, and a second linkage mechanism 7.

[0023] The seat frame 2 is movably supported above the fixed base frame 1. The backrest frame 3 is located behind the seat frame 2 and is hinged to the rear end of the seat frame 2. The drive unit 4 is mounted on the fixed base frame 1, and its retractable output end 41 is hinged to the backrest frame 3 for driving the backrest frame 3 to rotate around its hinge point with the seat frame 2 through telescopic movement.

[0024] Specifically, the seat frame 2 is movably supported above the fixed base frame 1 via a connecting structure, allowing the seat frame 2 to move relative to the fixed base frame 1 within a certain range. The backrest frame 3 is located behind the seat frame 2 and is hinged to the rear end of the seat frame 2 via a hinge shaft, allowing the backrest frame 3 to rotate forward or backward within a predetermined angle range around the hinge point. The drive device 4 is mounted on the fixed base frame 1 and has a retractable output end 41 (e.g., a piston rod or push rod), which is hinged to the backrest frame 3 via the hinge shaft. When the drive device 4 is working, its output end 41 retracts, transmitting force to the backrest frame 3 through the hinge connection, thereby driving the backrest frame 3 to rotate around the hinge point between it and the seat frame 2, achieving automatic adjustment of the backrest angle.

[0025] In some preferred embodiments, the drive device 4 can be a linear drive element such as an electric push rod, a gas spring, a hydraulic cylinder, or a linear motor. Furthermore, a controller can be electrically connected to the drive device 4 to control the tilt angle of the chair back frame 3 according to user commands or preset programs, thereby improving comfort and intelligence.

[0026] Furthermore, a first linkage mechanism 5 connects the backrest frame 3 and the seat frame 2. The first linkage mechanism 5 is configured to cause the seat frame 2 to rotate relative to the fixed base frame 1 when the backrest frame 3 is flipped. Specifically, when the drive device 4 drives the backrest frame 3 to flip around its hinge point with the seat frame 2, the first linkage mechanism 5 is configured to transmit the movement of the backrest frame 3 to the seat frame 2, thereby causing the seat frame 2 to rotate relative to the fixed base frame 1. Through the linkage action of this first linkage mechanism 5, the flipping action of the backrest frame 3 not only changes the angle of the office chair back but also simultaneously adjusts the tilt posture of the seat. It can be understood that the first linkage mechanism 5 may include at least one rigid link, with its two ends hinged to the backrest frame 3 and the seat frame 2 respectively, forming a four-bar linkage or a more complex linkage structure. The geometric arrangement of this linkage mechanism is designed so that when the backrest frame 3 tilts backward, it causes the front end of the seat frame 2 to rise upward and the rear end to sink downward, thereby achieving coordinated movement between the seat frame 2 and the backrest frame 3. This linkage mechanism requires no additional drive source; it can passively adjust the posture of the seat frame 2 simply by actively flipping the backrest frame 3. The structure is simple and highly reliable.

[0027] Furthermore, a second linkage mechanism 7 connects the backrest frame 3 and the footrest 6. The second linkage mechanism 7 is configured to adjust the angle of the footrest 6 relative to the seat frame 2 when the backrest frame 3 is flipped. Specifically, when the backrest frame 3 flips backward to increase the backrest angle, the second linkage mechanism 7 correspondingly drives the footrest 6 to unfold upward and raise its front end, placing the footrest in a raised position suitable for supporting the user's legs. Conversely, when the backrest frame 3 returns to its original position, the second linkage mechanism 7 simultaneously drives the footrest 6 to retract downward, bringing it close to the bottom of the seat frame 2, returning it to its retracted state. It can be understood that the second linkage mechanism 7 can be composed of one or more rigid links, with the links connected to each other and to the backrest frame 3 and footrest 6 via hinges, forming a multi-bar linkage mechanism. By rationally designing the position of each hinge point and the length of the connecting rod, coordinated linkage between the backrest movement and the footrest movement can be achieved. Without the need for additional drive devices, the footrest angle can be automatically adjusted while adjusting the backrest angle, improving operational convenience and user comfort.

[0028] Furthermore, by separately setting up the first linkage mechanism 5 and the second linkage mechanism 7, and connecting both to the backrest frame 3, the backrest frame 3 can simultaneously drive the seat frame 2 and the footrest 6 to adjust in a coordinated manner during the flipping process. This arrangement allows a single drive action of the backrest frame 3 to simultaneously trigger the rotation of the seat frame 2 relative to the fixed base frame 1 and the angle adjustment of the footrest 6 relative to the seat frame 2, achieving coordinated movement among the backrest, seat cushion, and footrest. This linkage mechanism avoids the complex structure of configuring independent drives for the seat frame 2 and the footrest 6, significantly simplifying the overall mechanical layout and reducing manufacturing costs and failure rates. On the other hand, since the movements of the seat frame 2 and the footrest 6 are determined by the flipping state of the backrest frame 3, the user only needs to operate one adjustment component (such as a switch or handle controlling the backrest tilt angle) to automatically obtain an ergonomic sitting or reclining support posture. Figure 4 As shown, when the backrest 3 is laid back, the front of the seat 2 is raised slightly to maintain thigh support, while the footrest 6 unfolds simultaneously to support the lower legs, effectively distributing body pressure and improving comfort, making it particularly suitable for rest, sleep, or rehabilitation scenarios. Figure 3 As shown, when the backrest 3 is retracted to the upright position, the seat frame 2 and footrest 6 are simultaneously reset, restoring the chair to a state suitable for normal sitting posture.

[0029] Therefore, this utility model provides a new office chair support 100, which utilizes a single drive source to achieve synchronous and linked adjustment of the angles of the seat frame 2 and footrest 6 through the flipping action of the backrest frame 3, with the aid of the first linkage mechanism 5 and the second linkage mechanism 7 respectively. This design only requires controlling the movement of the backrest frame 3 to coordinate the posture adjustment of the backrest, seat cushion, and footrest. When the backrest frame 3 is flat, the front of the seat rises, and the footrest rises simultaneously to form a comfortable reclining posture; when the backrest frame 3 returns to the upright position, the seat and footrest also return to the normal sitting position. The entire system requires only one drive device 4 and relies on a purely mechanical linkage mechanism to achieve efficient collaborative work of multiple components, which not only simplifies the structure but also improves the ease of use and ergonomic fit. In addition, since a mechanical linkage is used instead of a complex electronic control system, the durability and safety of the product are also enhanced.

[0030] In some embodiments of this utility model, the first linkage mechanism 5 includes a first link 51 and a second link 52. One end of the first link 51 is hinged to the backrest frame 3. One end of the second link 52 is hinged to the other end of the first link 51. The second link 52 has a support point 5201 on its body that is hinged to the fixed base frame 1, so that the fixed base frame 1 provides rotational support for the second link 52. The other end of the second link 52 is connected to the front end of the seat frame 2, and this connection is configured to allow the other end of the second link 52 to rotate relative to the seat frame 2 and slide along the front-rear direction of the seat frame 2.

[0031] like Figures 5-9 As shown, when the drive device 4 pushes the backrest frame 3 to flip backward around its hinge point with the rear end of the seat frame 2, the backrest frame 3 itself will cause the rear end of the seat frame 2 to shift accordingly. Simultaneously, the movement of the backrest frame 3 is transmitted to the front end of the seat frame 2 through the first linkage mechanism 5 (i.e., composed of the first link 51 and the second link 52), causing the second link 52 to push or pull the front end of the seat frame 2 to slide and rotate in the front-back direction. Because the rear end of the seat frame 2 is constrained by the backrest frame 3 and the front end is guided by the first linkage mechanism 5, the entire seat frame 2, under the coordinated action of both ends, produces a tilting motion around a momentary center of rotation, thereby achieving dynamic adjustment of the seat angle. This sliding-rotation composite connection not only ensures smooth motion transmission but also effectively adapts to the displacement changes of the seat frame 2 during adjustment, improving the motion coordination and structural stability of the linkage mechanism.

[0032] The seat frame 2 is hinged to the fixed base frame 1 via a connecting structure, forming a pivot point for rotation of the seat frame 2 relative to the fixed base frame 1. It should be noted that although the seat frame 2 is movably supported above the fixed base frame 1, its primary movement is not rotation around the hinge axis with respect to the fixed base frame 1, but rather a composite movement formed by the traction of the rear end of the backrest frame 3 and the drive of the front end of the first linkage mechanism 5. The fixed base frame 1 primarily provides support, rather than serving as the main hinge point for the tilting of the seat frame 2.

[0033] Therefore, the change in seat tilt angle is entirely determined by the backrest movement and its linkage mechanism, requiring no additional drive. By rationally arranging the length of the linkage and the hinge position, the amplitude and timing of the seat front lifting / lowering can be precisely controlled to match the human body's sitting posture needs at different backrest angles. Moreover, the rotation-sliding composite connection effectively absorbs geometric deviations during movement, preventing the mechanism from jamming and improving smooth operation. Thus, the tilting of the seat frame 2 is essentially achieved by the coordinated action of the backrest frame 3 and the first linkage mechanism 5 applied to both ends of the seat frame 2, embodying a flexible linkage mechanism of "dual-end drive, no fixed pivot," ensuring both freedom of movement and ergonomic rationality.

[0034] In a specific embodiment of this utility model, a sliding groove 21 extending in the front-rear direction is provided on the lower side of the front end of the chair frame 2, and a pin 5202 is provided at the other end of the second connecting rod 52. The pin 5202 passes through the sliding groove 21, so that the second connecting rod 52 can slide back and forth along the sliding groove 21 through the pin 5202, and can rotate relative to the chair frame 2 around the pin 5202.

[0035] Specifically, a groove 21 extending in the front-rear direction is provided on the lower side of the front end of the seat frame 2, and a pin 5202 is provided at the other end of the second connecting rod 52, which passes through the groove 21. With this structural configuration, the second connecting rod 52 can rotate relative to the seat frame 2 with the pin 5202 as the rotation center, while the pin 5202 can slide freely along the groove 21 in the front-rear direction, thus achieving a combined rotational and sliding motion. This connection method allows the second connecting rod 52 to both push or pull the front end of the seat frame 2 to tilt when transmitting the linkage action from the backrest frame 3, and to adapt to the displacement changes of the seat frame 2 during movement, effectively ensuring the smoothness and stability of the mechanism's operation.

[0036] In some embodiments of this utility model, the office chair support 100 further includes an elastic reset member, one end of which is connected to the first linkage mechanism 5 and the other end is connected to the fixed base frame 1, for providing auxiliary return force during the reset process of the chair back frame 3.

[0037] Specifically, one end of the elastic reset component is connected to the first linkage mechanism 5, and the other end is connected to the fixed base frame 1. When the chair back frame 3 resets from a flat position to an upright position, the elastic reset component is stretched or compressed, releasing its stored elastic potential energy. This releases an auxiliary return force on the first linkage mechanism 5, which is then transmitted to the chair back frame 3 and the seat frame 2 through the first linkage mechanism 5, assisting them in smoothly and quickly returning to their initial sitting position. This elastic reset component not only helps reduce the load on the drive device 4 during the reset process, improving the overall responsiveness and smoothness of the movement, but also provides a certain degree of self-reset capability in scenarios such as power outages or manual adjustments, enhancing the product's safety and ease of use. Optionally, the elastic reset component can be in the form of a tension spring, compression spring, torsion spring, or elastic rubber element, and the specific arrangement can be flexibly set.

[0038] In some embodiments of this utility model, the second linkage mechanism 7 includes a third linkage 71 and a linkage component 72. One end of the third linkage 71 is hinged to the backrest frame 3. The linkage component 72 is connected between the third linkage 71 and the footrest 6, and is hinged to the seat frame 2 to obtain a pivot point. When the backrest frame 3 is flipped, the third linkage 71 drives the linkage component 72 to move around the pivot point, thereby causing the footrest 6 to adjust its angle relative to the seat frame 2.

[0039] Specifically, one end of the third link 71 is hinged to the backrest frame 3, and the other end is connected to the linkage component 72. The linkage component 72 is connected between the third link 71 and the footrest 6, and is also hinged to the seat frame 2, thus using this hinge point as a fulcrum for rotation. When the backrest frame 3 flips, its movement is transmitted to the linkage component 72 through the third link 71. Since the specific position of the linkage component 72 is fixed to the seat frame 2 by hinge, forming a stable fulcrum for rotation, the input force of the third link 71 will cause the linkage component 72 to rotate around this fulcrum. This rotational movement is further transmitted to the footrest 6, driving the footrest 6 to lift and unfold relative to the seat frame 2, raising its front end to provide effective support for the user's legs. Conversely, when the backrest frame 3 returns to its upright position, the third link 71 moves in the opposite direction, causing the linkage component 72 to swing in the opposite direction around the same pivot point, thereby causing the footrest 6 to retract downwards synchronously and finally rest against the bottom of the seat frame 2, restoring it to the storage state required for a normal sitting posture, thus achieving adaptive adjustment of the footrest angle.

[0040] It is worth noting that, since the pivot point of the linkage component 72 is set on the seat frame 2, and the seat frame 2 itself rotates relative to the fixed base frame 1 through the first linkage mechanism 5 during the flipping of the backrest frame 3, the movement of the footrest 6 is not only directly driven by the backrest frame 3 through the third linkage 71 and the linkage component 72, but is also indirectly affected by the changes in the posture of the seat frame 2. Specifically, when the backrest frame 3 flips backward, on the one hand, the third linkage 71 pushes the linkage component 72 to swing around its hinge point with the seat frame 2, causing the footrest 6 to unfold; on the other hand, the seat frame 2 tilts synchronously due to the action of the first linkage mechanism 5 (e.g., the front end lifts up), causing the pivot point of the linkage component 72 to undergo spatial displacement and angular deflection, thereby further adjusting the driving direction and stroke of the linkage component 72 on the footrest 6.

[0041] This dual-linkage mechanism allows the footrest 6 to respond simultaneously to changes in the backrest angle and seat tilt angle, automatically achieving a support posture that better conforms to the natural curves of the lower limbs as the user transitions from a sitting position to a semi-reclined or fully reclined position. For example, as the front of the seat rises, the footrest not only extends upwards, but its extension angle is also dynamically optimized due to changes in the fulcrum position, preventing the lower legs from dangling or the knees from excessive bending. This design fully utilizes the coordinated motion relationship between the seat frame 2 and the backrest frame 3, transforming potentially interfering multi-degree-of-freedom adjustments into mutually reinforcing linkage logic, significantly improving the adaptability and comfort of the footrest support, while maintaining the simplicity and reliability of a purely mechanical structure, achieving highly coordinated posture adjustment without the need for additional sensors or control units.

[0042] In one embodiment of this utility model, the linkage component 72 includes a fourth link 7201, a fifth link 7202, and a sixth link 7203, which together constitute a multi-bar linkage mechanism connected to the seat frame 2, the third link 71, and the footrest 6. One end of the fourth link 7201 is hinged to the lower side of the front end of the seat frame 2, and the fourth link 7201 has a hinge point on its body that is hinged to the third link 71. Both ends of the fifth link 7202 are respectively hinged to the other end of the fourth link 7201 and to the footrest 6. One end of the sixth link 7203 is hinged to the lower side of the front end of the seat frame 2, and this hinge point is located in front of the hinge point between the fourth link 7201 and the seat frame 2. The other end of the sixth link 7203 is hinged to the connection point provided on the fifth link 7202.

[0043] Specifically, one end of the fourth link 7201 is hinged to the lower side of the front end of the seat frame 2, forming a basic rotation fulcrum of the linkage assembly 72; the body of the fourth link 7201 also has another hinge point for hinged to the third link 71, thereby receiving the drive input from the backrest frame 3. The fifth link 7202, as the main transmission component connecting the footrest 6, has one end hinged to the other end of the fourth link 7201, and the other end hinged to the footrest 6, transmitting motion to the footrest 6 to adjust its angle. One end of the sixth link 7203 is also hinged to the lower side of the front end of the seat frame 2, and this hinge position is located in front of the hinge point between the fourth link 7201 and the backrest frame, forming a spatially staggered double fulcrum layout; the other end of the sixth link 7203 is hinged to a specific connection point on the fifth link 7202, constituting auxiliary support and motion constraint for the fifth link 7202.

[0044] Through the above arrangement, the fourth link 7201, the fifth link 7202, and the sixth link 7203, together with the seat frame 2, form a planar four-bar or five-bar linkage system with two fixed hinge fulcrums (both located on the lower front side of the seat frame 2). When the backrest frame 3 flips, the third link 71 pushes the fourth link 7201 to swing around its hinge point with the seat frame 2, thereby driving the fifth link 7202 to move; at the same time, the sixth link 7203, with its front fulcrum as a reference, guides and limits the movement trajectory of the fifth link 7202, ensuring that the footrest 6 maintains a stable and controllable posture change during unfolding or folding.

[0045] Since multiple hinge points of the entire linkage assembly 72 are located on the seat frame 2, and the seat frame 2 itself tilts with the movement of the backrest frame 3, the linkage assembly 72 not only responds to the direct drive of the backrest frame 3, but also adaptively adjusts itself in sync with the posture changes of the seat frame 2. This structural design allows the movement of the footrest 6 to comprehensively reflect the dual states of the backrest angle and the seat tilt angle, achieving more precise and ergonomic leg support, while avoiding movement interference or jamming, and improving the overall coordination, reliability, and comfort of the mechanism.

[0046] Furthermore, the linkage assembly 72 also includes a seventh link 7204, one end of which is hinged to the connection point on the body of the fourth link 7201 located between its two ends, and the other end is hinged to the foot bracket 6.

[0047] Specifically, when the fourth link 7201 swings under the drive of the third link 71, the intermediate connection point on its body is displaced in a specific direction, and then the additional driving force or guiding force is transmitted to the footrest 6 through the seventh link 7204. This force works in conjunction with the main driving force transmitted by the fifth link 7202 to keep the footrest 6 stable and wobble-free during lifting or closing, and to achieve more complex movement paths to better conform to the user's leg contours.

[0048] This design, by adding a seventh link 7204, creates a more stable multi-bar parallel transmission structure in the linkage assembly 72. This seventh link 7204, together with the existing fifth link 7202, acts on the footrest 6, forming a dual-point drive or dual-point constraint on the footrest 6. This not only enhances the structural rigidity of the footrest 6 during movement but also effectively controls its unfolding trajectory and final posture. Furthermore, the introduction of the seventh link 7204 increases the constraint degree of freedom of the second linkage mechanism 7, improving the overall durability of the mechanism. At the same time, this design still relies entirely on the single input action of the backrest frame 3, retaining the simplicity and reliability of pure mechanical linkage while significantly optimizing the precision and comfort of footrest adjustment.

[0049] In another embodiment of this utility model, the linkage assembly 72 includes: an eighth link, a ninth link, and a tenth link. One end of the eighth link is hinged to the lower side of the front end of the chair seat frame 2, and the eighth link has a hinge point on its body that is hinged to the third link 71. Both ends of the ninth link are respectively hinged to the other end of the eighth link and to the footrest 6. One end of the tenth link is hinged to the lower side of the front end of the chair seat frame 2, and this hinge point is located in front of the hinge point between the eighth link and the chair seat frame 2. The tenth link has a hinge point on its body that is hinged to the ninth link. One end of the eleventh link is hinged to the other end of the tenth link, and the other end of the eleventh link is hinged to the footrest 6.

[0050] It is understood that, unlike the aforementioned embodiments, the linkage component 72 in this embodiment includes an eighth link, a ninth link, a tenth link, and an eleventh link, which together constitute a multi-link linkage mechanism with a different structural form than the aforementioned embodiments but with the same functional objective, used to realize the function of automatically adjusting the angle of the footrest 6 as the chair back frame 3 flips.

[0051] Specifically, one end of the eighth link is hinged to the lower front side of the seat frame 2, forming a basic rotation fulcrum of the linkage assembly 72. The body of the eighth link also has another hinge point for hinged to the third link 71, thereby receiving drive input from the backrest frame 3. Both ends of the ninth link are hinged to the other end of the eighth link and the footrest 6, respectively, serving as the main transmission path to transmit motion to the footrest 6. One end of the tenth link is also hinged to the lower front side of the seat frame 2, and this hinge position is located in front of the hinge point between the eighth link and the seat frame 2, forming a front-to-back dual-fulcrum support layout. The body of the tenth link has an intermediate hinge point for hinged to the ninth link, used to guide and constrain the movement of the ninth link. Furthermore, one end of the eleventh link is hinged to the other end of the tenth link, and its other end is hinged to the footrest 6, thereby providing the footrest 6 with an additional connection point and driving force path.

[0052] The linkage component 72, through the coordinated operation of links 8 to 11, constructs a planar multi-bar mechanism on the lower front side of the seat frame 2. This mechanism has two fixed fulcrums (the hinge points of the eighth and tenth links with the seat frame 2) and includes multiple movable hinge relationships. When the backrest frame 3 flips, the third link 71 pushes the eighth link to swing, causing the ninth link to move. Simultaneously, the tenth link, using its front fulcrum as a reference, interacts with the middle hinge point of the ninth link to adjust the posture of the ninth link, and transmits additional motion input to the footrest 6 through the eleventh link. Thus, the footrest 6 achieves smooth and controllable angle adjustment under the dual drive of the ninth and eleventh links.

[0053] Compared to the aforementioned embodiment using the fourth to seventh links 7204, this embodiment differs in the number of links, connection sequence, and hinge topology. However, it still utilizes the seat frame 2 as the mounting reference for the linkage component 72, and leverages the tilting motion of the seat frame 2 itself to dynamically modulate the footrest posture. This structural variation, while maintaining the core function of "synchronously driving the coordinated movement of the seat and footrest through a single movement of the backrest," provides different kinematic characteristics and mechanical transmission paths, allowing for flexible selection based on product space layout, cost control, or performance requirements.

[0054] In summary, this embodiment further demonstrates the flexibility and scalability of the present invention in terms of mechanism design, ensuring both the ergonomic adaptability of the footrest adjustment and maintaining the high reliability and low complexity advantages of pure mechanical linkage.

[0055] In some embodiments of this utility model, the chair back frame 3 extends in the vertical direction, and the angle between it and the horizontal plane of the ground is α, which satisfies the relationship: 100°<α<160°.

[0056] It is understandable that this angle range is set with full consideration of the natural physiological curvature of the human spine and the need for comfortable support in office or rest scenarios. When α is greater than 100°, the backrest frame 3 is in a moderately reclined state, which can effectively relieve the pressure on the user's lower back and avoid fatigue caused by prolonged upright sitting. When α is less than 160°, it ensures that the backrest does not recline excessively, thereby maintaining basic stability in a reclining position and preventing the user from slipping or experiencing operational inconvenience. Especially during the process of adjusting the backrest frame 3 from a sitting position to a semi-reclining position, this angle range can balance support, comfort, and functionality, making it suitable for various usage modes such as office work, reading, and short rest. In addition, since the linkage action of the seat frame 2 and the footrest 6 is based on the flipping movement of the backrest frame 3 within this angle range, this limitation also helps to ensure that the first linkage mechanism 5 and the second linkage mechanism 7 operate smoothly within a reasonable stroke, avoiding the mechanism from being at a dead point or extreme position, and improving the reliability and service life of the overall structure.

[0057] Preferably, the angle α between the backrest frame 3 and the horizontal plane of the ground satisfies: 110°≤α≤155°. This preferred angle range further optimizes the user experience of the chair during daily office work and light rest. When α is greater than or equal to 110°, the backrest provides a moderate recline, which helps to distribute the load on the lumbar spine and improve the comfort of sitting for long periods of time; while when α is less than or equal to 155°, it can effectively avoid problems such as the body sliding forward, inconvenience of operation, or spatial interference caused by the backrest being too flat. Within this range, the flipping movement of the backrest frame 3 can be well coordinated with the first linkage mechanism 5 and the second linkage mechanism 7 to ensure that the front end of the seat frame 2 is moderately raised and the footrest 6 is smoothly unfolded, realizing ergonomic linkage posture adjustment, while ensuring that each linkage mechanism is in the efficient transmission range and avoiding dead points or overload.

[0058] In some embodiments of this utility model, the chair frame 2 extends in the front-to-back direction, and the angle between it and the horizontal plane of the ground is β, which satisfies the relationship: 0≤β<15°.

[0059] Understandably, this angle range ensures that the chair provides comfortable support while maintaining good posture stability. When β is 0°, the seat frame 2 is completely horizontal, suitable for standard office sitting posture. As β gradually increases but remains below 15°, the front end of the seat frame 2 is slightly raised, forming a slightly tilted seat surface. This helps guide the pelvis forward tilt, maintain the natural physiological curvature of the lumbar spine, and reduce pressure on the back of the thighs, improving comfort during long periods of sitting. Especially when the backrest 3 is laid flat, the moderate positive tilt angle effectively prevents the user's body from sliding forward. Furthermore, since the tilt angle of the seat frame 2 is controlled by the first linkage mechanism 5, limiting β to < 15° avoids instability of the center of gravity or difficulty in getting in and out of the seat due to excessive lifting of the front end of the seat. At the same time, it ensures that the linkage mechanism operates within a reasonable range of motion, preventing structural interference or stress concentration.

[0060] Preferably, the angle β between the seat frame 2 and the horizontal plane of the ground satisfies: 0°≤β≤10°. This preferred range further optimizes the posture support performance of the chair during the linkage adjustment process. When β is 0°, the seat frame 2 remains horizontal, suitable for regular office work or upright sitting posture; when β is between 0° and 10°, the front end of the seat frame 2 is slightly raised, forming a slightly tilted seat surface, which helps guide the pelvis to a neutral or slightly forward tilted position, thereby better matching the lumbar support requirements when the backrest frame 3 is reclined, reducing the pressure on the bottom of the thighs, and improving comfort. At the same time, limiting the maximum tilt angle to within 10° can effectively avoid problems such as the center of gravity shifting backward, difficulty getting up, or unstable sitting posture caused by the front end of the seat being raised too high, especially in office work or frequent posture change scenarios, taking into account both ergonomic benefits and operational safety. In addition, this angle range also ensures that the first linkage mechanism 5 is always in an efficient and stable motion range when driving the chair frame 2 to rotate, avoiding the linkage from approaching the limit position or generating excessive transmission resistance, which helps to improve the overall durability and smoothness of response of the mechanism.

[0061] An office chair support 100 according to a second aspect embodiment of the present invention includes: a fixed base frame 1, a seat frame 2, a backrest frame 3, a drive device 4, a first linkage mechanism 5, a footrest 6, and a second linkage mechanism 7. The seat frame 2 is movably supported above the fixed base frame 1. The backrest frame 3 is located behind the seat frame 2 and is hinged to the rear end of the seat frame 2. The drive device 4 is mounted on the fixed base frame 1, and its retractable output end 41 is hinged to the backrest frame 3, for driving the backrest frame 3 to rotate around its hinge point with the seat frame 2 via a telescopic movement. The first linkage mechanism 5 is connected between the backrest frame 3 and the seat frame 2, and is hinged to the fixed base frame 1. The first linkage mechanism 5 is configured to drive the seat frame 2 to rotate relative to the fixed base frame 1 when the backrest frame 3 rotates. The second linkage mechanism 7 is connected between the backrest frame 3 and the footrest 6, and is hinged to the seat frame 2. The second linkage 7 is configured to move with the rotation of the backrest 3 and the seat frame 2 when the backrest 3 is flipped, so as to drive the footrest 6 to adjust the angle relative to the seat frame 2.

[0062] Unlike the aforementioned office chair support 100, the first linkage mechanism 5 connects the backrest frame 3 and the seat frame 2, and is also hinged to the fixed base frame 1, providing a stable fulcrum for the first linkage mechanism 5. When the backrest frame 3 flips under the action of the drive device 4, this movement is transmitted through the first linkage mechanism 5, and a lever effect is generated by its hinge point with the fixed base frame 1, thereby causing the seat frame 2 to rotate relative to the fixed base frame 1, achieving dynamic adjustment of the seat tilt angle. This structure ensures that the posture change of the seat frame 2 is actively driven by the backrest movement, without the need for additional actuators. At the same time, the hinge support provided by the fixed base frame 1 ensures the stability of the linkage movement and the reliability of force transmission. Furthermore, the second linkage mechanism 7 connects the backrest frame 3 and the footrest 6, and is hinged to the seat frame 2, using the seat frame 2 as its fulcrum for rotation. During the flipping of the backrest frame 3, the second linkage mechanism 7 is not only directly driven by the backrest frame 3, but also changes in spatial position and angle along with the linkage rotation of the seat frame 2. Since its rotation fulcrum is located on the seat frame 2, the adjustment action of the footrest 6 can simultaneously respond to the dual changes in the backrest angle and seat inclination angle, thus more accurately adapting to the user's leg support needs in different postures. When the backrest is flattened and the front of the seat is raised, the second linkage mechanism 7 automatically adjusts the driving direction and stroke of the footrest 6 based on the new fulcrum position, making the footrest unfolding angle more ergonomic.

[0063] Therefore, by setting the rotation fulcrum of the first linkage mechanism 5 on the fixed base frame 1 and the rotation fulcrum of the second linkage mechanism 7 on the seat frame 2, this utility model realizes the coordinated linkage between the backrest, seat cushion and footrest. The adaptive adjustment of multiple components can be completed by a single drive source. The structure is simple, the action is reliable, and no complex control logic is required. While improving comfort, it significantly enhances the integration and practicality of the product.

[0064] In some embodiments of this utility model, there are two sets of first linkage mechanisms 5, symmetrically arranged on the left and right sides of the fixed base frame 1. Each set of first linkage mechanisms 5 is connected between the backrest frame 3 and the seat frame 2. When the backrest frame 3 is flipped, the first linkage mechanisms on both sides move synchronously, coordinating to drive the seat frame 2 to rotate smoothly relative to the fixed base frame 1, achieving uniform adjustment of the seat tilt angle and avoiding uneven loading or jamming caused by unilateral force. Similarly, there are two sets of second linkage mechanisms 7, symmetrically arranged on the left and right sides of the fixed base frame 1, respectively connected to the corresponding backrest frame 3, footrest 6, and seat frame 2. During the flipping of the backrest frame 3, the second linkage mechanisms 7 on both sides receive drive input from the backrest frame 3, ensuring consistent movement and balanced support of the footrests on both sides, effectively conforming to the natural posture of the user's legs. By configuring both the first linkage mechanism 5 and the second linkage mechanism 7 as a left-right symmetrical double-pair structure, the left-right synchronization and balance of the seat frame 2 and footrest 6 during the adjustment process are ensured, avoiding tilting, twisting or abnormal noise, and significantly enhancing the comfort, safety and durability of use.

[0065] In the description of this utility model, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this utility model and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model.

[0066] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example.

[0067] Although embodiments of the present invention have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the claims and their equivalents.

Claims

1. An office chair frame, characterized in that, include: Fixed base frame (1); A chair seat frame (2) is movably supported above the fixed base frame (1); The backrest frame (3) is located behind the seat frame (2) and is hinged to the rear end of the seat frame (2); Drive device (4), the drive device (4) is mounted on the fixed base frame (1), and its retractable output end (41) is hinged to the backrest frame (3) for driving the backrest frame (3) to rotate around its hinge point with the seat frame (2) through telescopic movement; The first linkage mechanism (5) is connected between the chair back frame (3) and the chair seat frame (2), and is configured to drive the chair seat frame (2) to rotate relative to the fixed base frame (1) when the chair back frame (3) is flipped. Footrest (6); The second linkage mechanism (7) is connected between the backrest frame (3) and the footrest frame (6) and is configured to drive the footrest frame (6) to adjust the angle relative to the seat frame (2) when the backrest frame (3) is flipped.

2. The office chair bracket according to claim 1, characterized in that, The first linkage mechanism (5) includes: The first link (51) has one end hinged to the chair back frame (3); The second link (52) has one end hinged to the other end of the first link (51), and the second link (52) has a support point (5201) on its body that is hinged to the fixed base frame (1) so that the fixed base frame (1) provides rotational support for the second link (52); the other end of the second link (52) is connected to the front end of the chair frame (2), and the connection is configured to allow the other end of the second link (52) to rotate relative to the chair frame (2) and slide along the front-rear direction of the chair frame (2).

3. The office chair bracket according to claim 2, characterized in that, The lower side of the front end of the chair frame (2) is provided with a sliding groove (21) extending in the front-back direction. The other end of the second connecting rod (52) is provided with a pin (5202). The pin (5202) passes through the sliding groove (21), so that the second connecting rod (52) slides back and forth along the sliding groove (21) through the pin (5202) and rotates relative to the chair frame (2) around the pin (5202).

4. The office chair bracket according to claim 1, characterized in that, The second linkage mechanism (7) includes: The third link (71) is hinged at one end to the chair back frame (3); Linkage component (72) is connected between the third link (71) and the footrest (6), and the linkage component (72) is hinged to the seat frame (2) to obtain a rotation fulcrum; when the backrest frame (3) is flipped, the third link (71) drives the linkage component (72) to move around the rotation fulcrum, thereby causing the footrest (6) to adjust its angle relative to the seat frame (2).

5. The office chair bracket according to claim 4, characterized in that, The linkage component (72) includes: The fourth link (7201) has one end hinged to the lower side of the front end of the chair frame (2), and the fourth link (7201) has a hinge point on its body that is hinged to the third link (71). The fifth link (7202) has two ends that are respectively hinged to the other end of the fourth link (7201) and the foot bracket (6); The sixth link (7203) has one end hinged to the lower side of the front end of the chair frame (2), and the hinge point is located in front of the hinge point between the fourth link (7201) and the chair frame (2). The other end of the sixth link (7203) is hinged to the connection point provided on the fifth link (7202).

6. The office chair bracket according to claim 5, characterized in that, The linkage assembly (72) further includes a seventh link (7204), one end of which is hinged to the connection point between the two ends of the fourth link (7201) body, and the other end is hinged to the foot bracket (6).

7. The office chair bracket according to claim 4, characterized in that, The linkage component (72) includes: The eighth link, one end of which is hinged to the lower side of the front end of the chair frame (2), and the eighth link has a hinge point on its body that is hinged to the third link (71); The ninth link, the two ends of which are respectively hinged to the other end of the eighth link and the foot bracket (6); The tenth link has one end hinged to the lower side of the front end of the chair frame (2), and the hinge point is located in front of the hinge point between the eighth link and the chair frame (2). The tenth link has a hinge point on its body that is hinged to the ninth link. The eleventh link, one end of which is hinged to the other end of the tenth link, and the other end of which is hinged to the foot bracket (6).

8. The office chair bracket according to claim 1, characterized in that, The chair back frame (3) extends vertically, and the angle between it and the horizontal plane of the ground is α, where α satisfies the following relationship: 100° < α < 160°; and / or The chair frame (2) extends in the front-to-back direction, and the angle between it and the horizontal plane of the ground is β, and β satisfies the relationship: 0≤β<15°.

9. The office chair bracket according to claim 1, characterized in that, Also includes: An elastic reset member, one end of which is connected to the first linkage mechanism (5) and the other end of which is connected to the fixed base frame (1), is used to provide auxiliary return force during the reset process of the chair back frame (3).

10. An office chair frame, characterized in that, include: Fixed base frame (1); A chair seat frame (2) is movably supported above the fixed base frame (1); The backrest frame (3) is located behind the seat frame (2) and is hinged to the rear end of the seat frame (2); Drive device (4), the drive device (4) is mounted on the fixed base frame (1), and its retractable output end (41) is hinged to the backrest frame (3) for driving the backrest frame (3) to rotate around its hinge point with the seat frame (2) through telescopic movement; A first linkage mechanism (5) is connected between the chair back frame (3) and the chair seat frame (2), and the first linkage mechanism (5) is hinged to the fixed base frame (1); the first linkage mechanism (5) is configured to drive the chair seat frame (2) to rotate relative to the fixed base frame (1) when the chair back frame (3) is flipped. Footrest (6); The second linkage mechanism (7) is connected between the backrest frame (3) and the footrest frame (6), and the second linkage mechanism (7) is hinged to the seat frame (2); the second linkage mechanism (7) is configured to move with the rotation of the backrest frame (3) and the seat frame (2) when the backrest frame (3) is flipped, so as to drive the footrest frame (6) to adjust the angle relative to the seat frame (2).

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