CHAIR UNIT AND FURNITURE ASSEMBLY WITH FLOOR-STANDING ARMRESTS

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001]The present disclosure claims the priority of Chinese Patent Application No. 2024113790261 filed on Sep. 30, 2024 before CNIPA. All the above are hereby incorporated by reference in their entirety.

TECHNICAL FIELD

[0002]The present disclosure relates to a leg unit for a movable chair unit, and additionally, the present disclosure further relates to a movable chair unit.

BACKGROUND

[0003]A variety of movable chair units are known in the prior art, such as sofas or seats with multi-position transformation functions. With the improvement of people's living standards, the comfort requirements for sofas and chairs are also increasing. In the known design, the movable chair unit generally includes a mechanical stretching device, whereby it can be switched between a sitting position, a relaxing (or TV) position and a lying position. When the chair unit is switched from the sitting position to the relaxing position, the footrest of the chair unit extends forward, and the angle between the backrest and the seat cushion remains basically unchanged. When the chair unit is changed from the relaxing position to the lying position, the footrest extends further forward and upward than in the relaxing position, and the backrest reclines significantly. However, in the movable seats of existing designs, the leg stretching mechanism often adopts a multi-link telescopic structure, which leads to the disadvantages of complex structure and cumbersome installation process. In addition, due to the complex connection structure, there is also a risk of functional failure, such as kinematic interference between the leg unit and the chair unit and the backrest unit.

SUMMARY

[0004]In view of the above, the technical problem to be solved by the present disclosure is to provide a movable seat with a simpler structure and easier assembly.

[0011]Compared with the prior art, this leg unit has abandoned the traditional multi-link structure and adopts the mating connection of the leg slider with the leg frame. This simplifies the mechanical connection structure and enables simpler movement chains, which in turn reduces the risk of motion stagnation and dysfunction. More importantly, in the case where the leg frame itself has shape stability, the movable part of the leg unit, that is, the leg slider is slidably retained in the leg frame. As a result, the leg unit, as an independent unit in a modular configuration, can be applied to a wide variety of types of chair units. This significantly improves the field of application of movable leg units and can even be added to chair units that do not otherwise have a movable leg structure.

[0012]In addition, the outward opening of the guide rail not only simplifies the assembly difficulty of the leg slider and the guide rail, but also allows the leg slider to move laterally outside the chair unit rather than laterally inside, thereby avoiding motion interference with the actuating unit. This allows, on the one hand, for improved operational reliability of the mechanical stretching device and, on the other hand, for a narrower design of the leg unit for a compact and aesthetically pleasing construction.

[0013]In some implementations, the leg slider includes a slider, and the slider is shaped to fit into the guide rail, so that the leg slider is slidably supported in the guide rail.

[0014]In some implementations, the leg actuator acts between the leg frame and the leg slider. In some implementations, the leg unit further includes a guide crossbeam extended transversely between the pair of the leg sliders, an end of the leg actuator is connected to the leg crossbeam, and an opposite end of the leg actuator is arranged on a top side of the guide crossbeam. As a result, the leg actuator is arranged above the lowest point of the leg frame, in particular above the guide beam, thereby further reducing the space requirement of the leg beam in the height direction. In some implementations, the leg actuator is configured as a linear actuator and includes a motor head, a motor guide rail, and a motor slider capable of moving along the motor guide rail. In some implementations, the motor head is hinged to the leg beam by means of a motor bracket, and the motor slider is fixedly connected to the top side of the guide beam. Alternatively, the motor slider is hinged to the top side of the guide beam by means of the motor bracket.

[0015]In some implementations, the leg longitudinal beam includes at least one mounting tab, and the leg frame is connected to a bottom side of the seat frame by means of the mounting tab. In some implementations, a mounting plane is defined by the mounting tab, and the guide rail is extended obliquely with respect to the mounting plane. As a result, the leg slider raises up while sliding forward, which improves the user's comfort.

[0016]In some implementations, two ends of the leg crossbeam are fixedly connected to the leg longitudinal beam. Alternatively, both ends of the leg beam may also be fixedly connected to the seat unit. In some implementations, a front end of the leg slider is attached to a footrest plate, the footrest plate is folded at a front end of the leg longitudinal beam in the retracted position, and the footrest plate is unfolded forward with respect to the leg longitudinal beam.

[0017]In some implementations, the leg unit further includes a footrest link, the footrest link is pivoted at a front end of the leg slider, and the footrest link is fixedly connected to the footrest plate, so that the footrest plate is pivotally connected to the leg slider by means of the footrest link.

[0018]In some implementations, the leg unit further includes a reset member, and an end of the footrest link distal to the leg slider is capable of being flipped forward by means of the reset member. In a process of the leg unit being switched from the retracted position to the stretched position, the leg slider slides forward along the guide rail, and the reset member causes the footrest link to be flipped forward together with the footrest plate. In a process of the leg unit being switched from the stretched position to the retracted position, the leg slider slides backward along a leg guide part of the leg longitudinal beam, so that the footrest plate is stopped by the front end of the leg longitudinal beam or the front end of the seat unit of the chair unit and overcomes a reset force of the reset member to be flipped backward.

[0019]In some implementations, the reset member includes a torsion spring acting between the leg slider and the footrest link.

[0020]In some implementations, the reset member includes a stretching member acting between the seat frame and the footrest plate, for example, a tension spring or a cover that encloses the seat frame and the footrest plate.

[0021]In some implementations, the base unit includes a pair of fixing plates extended along the front-to-rear direction of the chair unit, and a rear-base crossbeam fixedly connected to the pair of fixing plates and extended transversely between the pair of fixing plates.

[0022]In some implementations, in order to further improve the stability of the chair unit, the base unit further includes a front-base crossbeam fixedly connected to the pair of fixing plates and extended transversely between the pair of fixing plates. Compared with the prior art, the leg unit according to the present disclosure is more flatly constructed and the actuating unit is arranged closer to the seat frame, thereby providing more space for the lower part of the chair unit, thereby providing spatial conditions for the setting of the front base crossbeam.

[0023]In some implementations, the seat unit includes a pair of seat support assembly movable along the front-to-rear direction of the chair unit with respect to the base unit, so as to achieve a switching of the seat unit between a reclined position and a vertical position, the seat support assembly includes an upper seat longitudinal beam and a lower seat longitudinal beam both extended along the front-to-rear direction of the chair unit, and the seat cushion is connected to the upper seat longitudinal beam by means of the seat frame. An angle between the seat frame and a horizontal plane is in a range of 6° to 12° when the seat unit is in the vertical direction, and in some implementations, the angle is 9°. The angle between the seat frame and a horizontal plane is in a range of 16° to 28° when the seat unit is in the reclined direction, and in some implementations, the angle is 20°.

[0024]The seat support assembly is configured as a frame structure with a stable shape. In such a construction, in some implementations, the seat support assembly further includes a front seat link and a rear seat link both fixedly connected between the upper seat longitudinal beam and the lower seat longitudinal beam. In some implementations, the upper seat longitudinal beam is directly fixedly connected to the lower seat longitudinal beam. This approach has greater advantages in strength and stability. Alternatively, the seat support assembly is configured as a one-piece unit, which is, for example, made by casting.

[0025]In some implementations, the chair unit further includes a backrest unit, configured to attach a backrest, in which the backrest unit is connected to a rear part of the upper seat longitudinal beam, the backrest unit includes a backrest support configured to attach the backrest, and the backrest support is pivotally connected to the upper seat longitudinal beam, so as to achieve a rotation of the backrest support with the switching of the seat unit between the reclined position and the vertical direction.

[0026]In some implementations, the backrest unit further includes a first backrest link and a second backrest link, the first backrest link is connected between the backrest support and the second backrest link, and the second backrest link is pivotally connected to the first backrest link, the upper seat longitudinal beam, and the base unit respectively, so that a highest point of the backrest support moves forward when the upper seat longitudinal beam moves forward.

[0027]In some implementations, an angle variation between the backrest support and a horizontal plane is greater than 40° when the chair unit is switched between the vertical position and the reclined position.

[0028]In some implementations, the actuating unit further includes a seat actuator acting between the leg crossbeam and the rear base crossbeam, and a movement of the seat support assembly along the front-to-rear direction of the chair unit is achieved by means of an adjustment of the seat actuator.

[0029]In order to solve the technical problems, the present disclosure is further related to a furniture assembly, including a pair of armrests fixedly support on the ground, a seat cushion movable with respect to the armrests, a backrest movable with respect to the armrests, a footrest extendable with respect to the armrests, and the aforementioned chair unit.

[0030]In some implementations, the furniture assembly further includes a leg enclosing part, the leg enclosing part encloses an accommodating chamber with a rectangular cross-section, the leg frame, the leg slider, and the actuating unit are at least partially accommodated in the accommodating chamber, which forms a leg movement module.

[0031]In some implementations, a width of the leg enclosing part is in a range of 200 mm to 400 mm.

[0032]In some implementations, the furniture assembly includes a front sealing plate, arranged on a front part of the furniture assembly and extended between the armrests, wherein the front sealing plate comprises a leg opening of rectangular construction, the leg movement module moves along the front-to-rear direction of the furniture assembly through the leg opening when the leg unit is switched between the retracted position and the stretched position.

[0033]Since the leg unit is constructed flat as a whole and the actuation unit, in particular the leg actuator and the seat actuator, are arranged in a compact manner, together with the leg unit, a compact assembly sufficient to be accommodated in the leg enclosing part is formed. The resulting leg movement module moves in the leg opening in a similar “draw out and push in” manner.

[0034]In some implementations, a ratio of a width of the leg opening to that of the front sealing plate is not more than 0.6. A ratio of a height of the leg opening to that of the front sealing plate is not more than 0.5. In some implementations, a height of the front sealing plate is not more than 280 mm. As a result, the leg unit is designed to be more compact.

BRIEF DESCRIPTION OF THE DRAWINGS

[0035]Embodiments of the present disclosure are described in detail below with reference to the accompanying drawings.

[0036]FIG. 1 schematically illustrates a perspective view of a chair unit according to an embodiment of the present disclosure in the sitting position;

[0037]FIG. 2 schematically illustrates a perspective view of the chair unit shown in FIG. 1 in the TV position;

[0038]FIG. 3 schematically illustrates a perspective view of the chair unit shown in FIG. 1 in the lying position;

[0039]FIG. 4 schematically shows a partial perspective view of the chair unit shown in FIG. 1;

[0040]FIG. 5 schematically shows a partial perspective view of the chair unit shown in FIG. 2;

[0041]FIG. 6 schematically shows a partial perspective view of the chair unit shown in FIG. 3;

[0042]FIG. 7 schematically illustrates a perspective view of the chair unit according to another embodiment of the present disclosure in the sitting position;

[0043]FIG. 8 schematically illustrates a perspective view of another direction of the chair unit shown in FIG. 7 in the TV position;

[0044]FIG. 9 schematically illustrates a perspective view of another direction of the chair unit shown in FIG. 7 in the lying position;

[0045]FIG. 10 schematically illustrates a side view of the chair unit according to the invention in the sitting position;

[0046]FIG. 11 schematically illustrates a side view of the chair unit shown in FIG. 10 in the TV position;

[0047]FIG. 12 schematically illustrates a side view of the chair unit shown in FIG. 10 in the lying position;

[0048]FIG. 13 schematically shows a top view of the chair unit according to the present disclosure in the sitting position;

[0049]FIG. 14 schematically illustrates a top view of the chair unit shown in FIG. 13 in the TV position;

[0050]FIG. 15 schematically illustrates a top view of the chair unit shown in FIG. 13 in the lying position;

[0051]FIG. 16 schematically illustrates a perspective view of a furniture assembly according to the present disclosure in the lying position;

[0052]FIG. 17 schematically illustrates a perspective view of the furniture assembly shown in FIG. 16 in another direction with the leg unit in the retracted position;

[0053]FIG. 18 schematically illustrates a perspective view of the furniture assembly shown in FIG. 16 in another direction with the leg unit in the stretched position; and

[0054]FIG. 19 schematically illustrates a partial front view of the furniture assembly according to the present disclosure.

DETAILED DESCRIPTION

[0055]The technical solutions in the embodiments of the present disclosure are clearly and completely described and discussed below in conjunction with the attached drawings of the embodiments of the present disclosure. Obviously, the embodiments described herein are only some of the embodiments of the present disclosure but not all of them. Based on the embodiments in the present disclosure, all other embodiments obtained by those skilled in the art without creative efforts fall within the scope of protection of the present disclosure.

[0056]References herein to “an embodiment” or “embodiments” refer to particular features, structures or characteristics that may be included in at least one embodiment of the present disclosure. In the description of the present disclosure, it is to be understood that the terms “up”, “down”, “left”, “right”, “top”, “bottom”, and other orientation or position relationships are based on the orientation or position relationships shown in the attached drawings. It is only intended to facilitate description of the present disclosure and simplify description, but not to indicate or imply that the referred device or element has a specific orientation, or is constructed and operated in a specific orientation. Therefore, they should not be construed as a limitation of the present disclosure. Furthermore, the related terms “first”, and “second” are used for descriptive purposes only and are not to be understood as indicating or implying relative importance or implicitly specifying the number of technical features indicated. As a result, a feature defined as “first” or “second” may expressly or implicitly include one or more such features. The terms “first”, “second” and the like are used to identify similar objects and are not intended to describe a particular sequence or order. It should be understood that the data herein used may be interchangeable in appropriate cases so that the embodiment of the present disclosure described herein may be implemented in an order other than what is illustrated or described herein.

[0057]In addition, it is also stated here that the “front-to-rear direction” described in the present disclosure is in terms of the stretched direction of the leg unit of the furniture assembly, in particular the chair unit. In particular, “front” refers to the direction towards the leg unit, and “rear” refers to the direction towards the backrest unit. “Left and right direction” or “horizontal direction” or “lateral direction” refers to the direction of the furniture assembly, especially the chair unit, which is perpendicular to the “front-to-rear direction” in the horizontal direction.

[0058]FIGS. 1 to 6 illustrate an example of a chair unit according to an embodiment of the present disclosure. As shown in FIG. 1, the chair unit includes a base unit 1, a seat unit 2, a backrest unit 3, a leg unit 4, and an actuating unit. The chair unit is configured to switch between a sitting position, a TV position, and a lying position.

[0059]In the sitting position shown in FIGS. 1 and 4, the backrest is upright, not shown, with the leg unit 4 in its retracted position; in the TV position shown in FIGS. 2 and 5, the leg unit 4 extends forward at its stretched position, where the backrest remains substantially unchanged; and, in the lying position shown in FIGS. 3 and 6, the leg unit 4 remains in its stretched position, with the seat unit 2 moving upward and tilting the backrest at a pronounced angle.

[0060]However, in embodiments not shown, the chair unit may also be switched only between the sitting position and the TV position, or only between the sitting position and the lying position.

[0061]The chair unit is configured as an armrest-standing type chair unit, which includes a pair of armrests 61 shown in FIGS. 16 to 19. The pair of armrests 61 are, on the one hand, directly or indirectly attached to the base unit 1, for example, by means of the armrest mounting plate 60 schematically shown in FIG. 1 attached to the base unit 1, and, on the other hand, fixedly supported on the ground, thereby supporting the chair unit “suspended” above the ground.

[0062]The following exemplary illustration illustrates the present disclosure by means of such a chair unit and a furniture assembly including the chair unit.

[0063]The base unit 1 has a fixing plate 12 extending longitudinally in the front-to-rear direction of the chair unit, a rear base crossbeam 13 extending transversely between the two fixing plates 12, which is fixedly connected to the inside of the armrest mounting plate 60 fixedly connected to the armrest 61, for example by means of riveting, threaded connection, and the rear end of the fixing plate 12 is fixedly connected to the rear base crossbeam 13 by means of a connecting strip 11 of a curved angle configuration. In order to further improve the stability of the base unit 1, a front base crossbeam 14 is also provided at the front of the fixing plate 12, and the front base crossbeam 14 is extended in a transverse direction between the fixing plates 12 and is fixedly connected thereto. The fixing plate 12, the connecting strip 11, the rear base crossbeam 13, and the front base crossbeam 14 are, for example, separate components that may be fixedly connected separately, whereas two or more of the fixing plate 12, the connecting strip 11, the rear base crossbeam 13, and the front base crossbeam 14 may also be configured as one-piece components.

[0064]Alternatively, however, in embodiments not shown, the base unit 1 may also have other structures, such as a base unit configured as a floor-standing metal frame, the fixing plate 12 of which is not fixedly attached to the inside of the armrests, but is provided with a plurality of legs extending downwardly from the fixing plate 12 for being supported on the ground; or the base unit does not have the fixing plate 12, but includes a rotating bracket rotatably supported on the ground.

[0065]In the embodiment shown according to FIGS. 1 to 6, the seat unit 2 includes a pair of seat support assemblies capable of moving in the front-to-rear direction of the chair unit relative to the base unit 1. The seat support assembly includes an upper seat longitudinal beam 21 and a lower seat longitudinal beam 24 extended along the front-to-rear direction of the chair unit, and includes a front seat link 22 and a rear seat link 23 both fixedly connected between the upper seat longitudinal beam 21 and the lower seat longitudinal beam 24. As a result, a frame structure with a stable shape is formed.

[0066]Alternatively, however, the seat support assembly may also have a structure other than a frame structure. For example, in the embodiment shown in FIGS. 7 to 9, the upper seat longitudinal beam 21 and lower seat longitudinal beam 24 are fixedly connected to each other directly, thereby providing greater stability and strength.

[0067]According to the present disclosure, the seat cushion 62 can be connected to the upper seat longitudinal beam 21 by means of the seat frame 20. As shown in FIGS. 1 to 3 and 16, the seat frame 20 is, on the one hand, fixedly connected to the seat cushion 62, and on the other hand, the bottom side of the seat frame 20 is connected to the top surface of the upper seat longitudinal beam 21. The seat frame 20 may be constructed of a hard material, for example, made of a wooden material. In addition, the seat frame 20 may also be made of a metal material. In some implementations, the seat frame 20 may be constructed in one piece with the upper seat longitudinal beam.

[0068]The rear part of the upper seat longitudinal beam 21 includes two upwardly oriented protrusions, i.e., a front seat frame protrusion 21a and a rear seat frame protrusion 21b.

[0069]The seat unit 2 is movably connected with respect to the base unit 1 by means of a linkage mechanism. However, in alternative embodiments, the seat unit 2 may also be configured to remain in the same relative position with respect to the base unit 1 at all times.

[0070]The linkage mechanism may include a plurality of links. In particular, as shown in FIG. 3, the linkage mechanism at least includes a front swing bar 17, a rear swing bar 18, a sub front swing bar 17a and a sub rear swing bar 18a. The lower ends of the front swing bar 17 and the rear swing bar 18 are pivotally connected to the fixing plate 12, respectively, the upper end of the sub front swing bar 17a is pivotally connected to the middle of the front swing bar 17, the lower end of the sub front swing bar 17a is pivotally connected to the lower end of the front seat link 22, the upper end of the sub rear swing bar 18a is pivotally connected to the middle of the rear swing bar 18, and the lower end of the sub rear swing bar 18a is pivotally connected to the lower end of the lower seat longitudinal beam 24. In addition, the linkage mechanism may also include at least an intermediate link 19a, the rear end of which is pivotally connected to the middle of the sub rear swing bar 18a, and the front end of which is pivotally connected to the top end of the front swing bar 17. Thus, the seat unit 2 is suspendedly supported on the fixing plate 12 by the linkage mechanism, so that the seat unit 2 can be switched between the vertical position as shown in FIGS. 1, 2, 4, 5, 7, 8, 10 and 11 and the reclined position as shown in FIGS. 3, 6, 9 and 12. An angle Y between the seat frame 20 and the horizontal plane EG is in a range of 6° to 12° when the seat unit is in the vertical direction, which, in some implementations, is 9°. The angle γ between the seat frame 20 and the horizontal plane EG is in a range of 16° to 28° when the seat unit is in the reclined direction, which, in some implementations, is 20°.

[0071]The backrest unit 3 is configured to mount the backrest (not shown) of the chair unit 2.

[0072]In some implementations, the backrest unit 3 is configured to be movable relative to the seat unit 2. However, in embodiments not shown, the backrest unit 3 can also be configured to always remain in a same relative position with respect to the seat unit 2.

[0073]In some implementations, the backrest unit 3 includes a backrest support 31 configured to be attached to the backrest mounting plate 63 as shown in FIG. 16, a first backrest link 32 and a second backrest link 33. A generally L-shaped configuration of the backrest support 31 is capable of pivotally connecting with respect to the upper seat longitudinal beam 21. The front end of the backrest support 31 is pivotally connected with the front seat frame protrusion 21a. The second backrest link 33 is configured as a crank member, including three pivot points, i.e., a pivot point located in the middle of the crank member and two pivot points located on two ends of the crank member, respectively. Hereby, the upper end of the second backrest link 33 is pivotally connected with the lower end of the first backrest link 32, the upper end of the first backrest link 32 is pivotally connected with the middle of the backrest support 31, and the second backrest link 33 is pivotally connected with the rear seat frame protrusion 21b by means of the pivot point in the middle. In addition, the backrest unit 3 also includes an auxiliary backrest link 34, an end of which is connected to the lower end of the second backrest link 33, and an opposite end is pivotally connected to the base unit 1, for example, in some implementations, to the connecting strip 11.

[0074]In some implementations, when the seat unit 2 is moved in the front-to-rear direction of the chair unit, the backrest support 31 is reclined and tilted forward accordingly, thereby enabling the backrest unit 3 to be switched with the seat unit 2 between the vertical position as shown in FIGS. 1, 2, 4, 5, 7, 8, 10 and 11 and the reclined position as shown in FIGS. 3, 6, 9 and 12. For example, when the seat unit 2 moves forward, the front end of the backrest support 31 hinged with the upper seat longitudinal beam 21 moves forward, while the second backrest link 33 rotates around a pivot point in the middle with the rear seat frame protrusion 21b and moves forward as a whole, thereby causing the backrest support 31 to pivot backward around its pivot point with the front seat frame protrusion 21a, thereby causing the backrest attached thereto to recline backward. An angle variation between the backrest support 31 and a horizontal plane is greater than 40° when the seat unit 2 is switched between the vertical position and the reclined position. For example, the angle β between the front side of the backrest support 31 and the horizontal plane EG is in a range of 100° to 115° when the seat unit is in the upright position, which, in some implementations, is 110°. The angle β between the front side of the backrest support 31 and the horizontal plane EG is in a range of 150° to 165° when the seat unit is in the reclined direction, which, in some implementations, is 159°.

[0075]According to the present disclosure, the leg unit 4 includes a pair of leg longitudinal beams 40, a leg crossbeam 41 transversely connected between the pair of leg longitudinal beams 40, a pair of leg sliders 42, a footrest plate 43 connected to the leg sliders 42. The respective leg slider 42 cooperates with the respective leg longitudinal beam 40 in a slidably guiding way to enable the respective leg slider 42 to drive the footrest plate 43 to move along the respective leg longitudinal beam 40 in the front-to-rear direction of the chair unit so that the leg unit 4 can be switched between the retracted position shown in FIGS. 1 and 4 and the stretched position shown in FIGS. 2, 3, 5 and 6. To achieve motion synchronization of the leg sliders 42, a guide crossbeam 44 is laterally connected between the leg sliders 42. In some implementations, the connection between the leg sliders 42 and the guide crossbeam 44 is achieved by welding, riveting, threading, etc. The guide crossbeam 44 is located in front of the leg crossbeam 41.

[0076]Two ends of the leg crossbeam 41 are fixedly connected to the leg longitudinal beam 40, and, in some implementations, the connection between the leg longitudinal beam 40 and the leg crossbeam 41 is achieved by such as welding, riveting, or threading, so as to form a leg frame with stable shape by means of the leg longitudinal beam 40 and the leg crossbeam 41.

[0077]Sliding guidance between the leg longitudinal beam 40 and the leg slider 42 can be achieved in a number of ways.

[0078]In some implementations, the leg longitudinal beam 40 is configured as a rail member. The leg longitudinal beam 40 includes a guide rail 40a having a C-shaped cross-section, the opening of the guide rail 40a opens laterally outwardly of the chair unit. Accordingly, the rear end of the leg slider 42 includes a slider 42b. The slider 42b is shaped to fit and movably fit in the guide rail 40a to achieve sliding guidance of the leg slider 42 along the leg longitudinal beam 40, thereby enabling a switching of the leg unit 4 between the retracted position and the stretched position.

[0079]The footrest plate 43 is generally configured as a plate that extends over at least a part of the transverse width of the chair unit. The rear end of the leg slider 42 is slidably embedded in the leg longitudinal beam 40 and the front end thereof is connected to the footrest plate 43. In some implementations, the leg slider 42 is connected to the footrest plate 43 by means of the footrest link 45 disposed at the front end of the leg slider 42. In particular, as shown in FIGS. 3 and 4, the footrest link 45 is configured with an L-shaped cross-section, a side of which is pivotally connected with the leg slider 42, and another side of which is fixedly connected with the footrest plate 43, for example, by riveting, threading, welding, etc.

[0080]In some implementations, the leg unit 4 further includes a reset member 46. In some implementations, the reset member 46 is configured as a torsion spring acting between the leg slider 42 and the footrest link 45. Under the biasing action of the reset member 46, the footrest link 45 tends to be flipped forward with its end away from the leg sliders 42.

[0081]As shown in FIG. 17, the leg unit 4 is in the retracted position, and the footrest link 45 is retracted at the front end of the leg longitudinal beam 40. The inner side of the footrest plate 43 is abutted against the front end of the chair unit, in particular the leg longitudinal beam 40, thereby overcoming the reset force applied by the reset member 46 and maintaining its retracted position. As shown in FIG. 18, the leg unit 4 is in the stretched position, where the footrest plate 43 is extended forward relative to the leg longitudinal beam 40.

[0082]During the switching of the leg unit 4 from the retracted position to the stretched position, the leg slider 42 slides forward so that the footrest plate 43 and the footrest link 45 attached thereto are disengaged from the stop of the leg longitudinal beam 40, and the footrest link 45 is flipped forward with its end away from the leg slider 42 under the biasing action of the reset member 46, thereby driving the footrest plate 43 to be flipped.

[0083]During the switching of the leg unit 4 from the stretched position to the retracted position, the leg slider 42 slides backward, driving the footrest link 45 along with the footrest plate 43 to slide backward. When the inner side of the footrest plate 43 is abutted against the front end of the leg longitudinal beam 40, the footrest plate 43 is flipped downward against the reset force of the reset member 46, thereby switching to the retracted position.

[0084]Of course, as an alternative, for example, in embodiments not shown, the reset member 46 may also be configured as a stretching member other than a torsion spring. For example, the seat cushion and footrest plate 43 of the chair unit are simultaneously covered by a coherent exterior, such as a sofa upholstery; or alternatively, the reset member 46 is configured to act as a tension spring between the footrest plate 43 and the seat frame.

[0085]The leg unit 4 is modularly configured as a whole. As previously described, a stably shaped leg frame is formed by two leg longitudinal beams 40 and a leg crossbeam 41. The movable parts of the leg unit 4, such as the leg slider 42, the guide crossbeam 44 connected between the leg sliders 42, the footrest link 45 connected to the leg sliders 42, and the footrest plate 43 are movably connected with respect to the leg frame. The leg unit 4 is configured as a relatively independent unit, which makes it widely applicable to a wide variety of chair units.

[0086]To mount the leg unit 4, at least one mounting tab may be provided on the leg frame, by means of which the leg unit 4 can be mounted on the seat frame of the chair unit or directly on the upper seat longitudinal beam 21, for example by means of riveting, threading, etc. The mounting tabs define a collective plane that does not interfere with the movement of the other parts of the chair unit. In some implementations, the mounting tab may be configured as a one-piece component with respect to the leg longitudinal beam 40, or as a component that is fixedly connected, for example, welded, riveted, threadedly connected, with respect to the leg longitudinal beam 40.

[0087]The leg longitudinal beam 40 includes at least two mounting tabs, namely a front mounting tab 48a and a rear mounting tab 48b at their front and rear ends, respectively. In some implementations, the mounting tabs are configured as bent members that protrude inwardly from the front and rear ends of the leg longitudinal beam 40, respectively, and have rivet holes or threaded holes for rivets or bolts to pass through. As shown in FIG. 10, the front mounting tab 48a and the rear mounting tab 48b together define a mounting plane E0 by which the leg unit 4 is mounted from below the chair unit to the bottom side of the seat frame 20. The guide rail 40a of the leg longitudinal beam 40 is in a plane E1 that extends obliquely with respect to the mounting plane E0, forming an acute angle between them. Thus, during the switching of the leg unit 4 from the retracted position to the stretched position, the leg slider 42 slides forward along the upwardly inclined guide part, thereby enabling the footrest plate 43 to reach a greater height, which, in some implementations, is above the height of the backrest, in the stretched position, achieving a “zero gravity” attitude.

[0088]As shown in FIGS. 13 to 15, the actuating unit includes a leg actuator 47 and a seat actuator 50 that act independently of each other.

[0089]The leg actuator 47 is, in some implementations, configured as a linear actuator that acts between the leg crossbeam 41 and the guide crossbeam 44. The leg actuator 47 includes a motor head 471, a motor guide 472 and a motor slider 473 movable along the motor guide 472. The motor head 471 is hinged to the leg crossbeam 41 by means of the motor bracket 471a, and the motor slider 473 is fixedly connected to the upper side of the guide crossbeam 44. By adjusting the leg actuator 47, the distance between the motor slider 473 and the motor head 471 changes, therefore the distance between the guide crossbeam 44 and the leg crossbeam 41 is driven to be increased or decreased, thereby achieving the switching between the retracted position and the stretched position of the leg unit 4.

[0090]Alternatively, the motor head 471 may be fixedly connected to the leg crossbeam 41, while the motor slider 473 may be pivotally connected to the guide crossbeam 44 by means of a bracket with a hinge.

[0091]Since the leg actuator 47 is not operatively connected to the seat unit 2 or the backrest unit 3, the adjustment of the leg actuator 47 does not affect the position of the seat unit 2 and the backrest unit 3.

[0092]In some implementations, the seat actuator 50 is configured as a linear actuator including a motor head acting between the base unit 1 and the seat unit 2 and an actuator rod retractable with respect to the motor head. The motor head of the seat actuator 50 can be mounted on the base unit 1, which, in some implementations, is mounted on the rear base crossbeam 13. The actuator rod of the seat actuator 50 can be mounted on the leg crossbeam 41 of the leg unit 4. With the adjustment of the seat actuator 50, the leg crossbeam 41 can be moved back and forth, and drive the seat frame 20 indirectly connected to the leg crossbeam 41, together with the upper seat longitudinal beam 21, to move back and forth, and drive the backrest to be tilted.

[0093]The seat actuator 50 and the leg actuator 47 can operate independently of each other, so that adjustment of the seat unit 2 and the backrest unit between the upright position and the reclined position can be performed independently with respect to the adjustment of the leg unit 4 between the retracted position and the stretched position. Thus, by the combined action of the seat actuator 50 and the leg actuator 47, the chair unit is switched between a sitting position, a TV position, and a lying position.

[0094]As shown in FIG. 13, neither the leg actuator 47 nor the seat actuator 50 is stretched, the leg unit 4 is in the retracted position, the seat unit 2 and the backrest unit 3 are in the upright position, and overall, the chair unit is in the sitting position. As shown in FIG. 14, only the leg actuator 47 is stretched, while the seat actuator 50 is not stretched, at which point the leg unit 4 is switched to the stretched position, in which the leg slider 42 protrudes forward from the guide rail 40a, the seat unit 2 and the backrest unit 3 are in the upright position, and overall, the chair unit is in the TV position. As shown in FIG. 15, the leg actuator 47 and the seat actuator 50 are both stretched, the leg unit 4 is in the stretched position, the seat unit 2 and the backrest unit 3 are in the reclined position, the leg unit 4, compared to the TV position, is pushed further forward, and overall, the chair unit is in the lying position.

[0095]As shown in FIGS. 16 to 18, the furniture assembly includes the aforementioned chair unit and a pair of armrests 61 fixedly supported on the ground, a seat cushion 62 movable relative to the armrests 61, a backrest mounting plate 63, and a footrest 64. The armrest 61 is fixedly connected to the fixing plate 12 of the base unit 1 by means of the armrest mounting plate 60, the seat cushion 62 is attached to the seat unit 2 by means of the seat frame 20, the backrest mounting plate 63 is fixedly connected to the backrest support 31 (not shown), and the footrest 64 is connected to the leg slider 42 of the leg unit 4 by means of the footrest plate 43. A front sealing plate 65 extending between the armrests 61 is provided at the front of the furniture assembly, which generally blocks the interior space of the furniture assembly from the front.

[0096]The furniture assembly also includes a leg enclosing part 66 that encloses an accommodating chamber having a rectangular cross-section, in which the width DO of the leg enclosing part 66 is 200 mm to 400 mm. The leg frame, leg slider 42, leg actuator 47, and seat actuator 50 are at least partially accommodated in the accommodating chamber, thereby forming a leg movement module, in which the footrest plate 43 protrudes from a front end opening of the leg enclosing part 66.

[0097]To facilitate the movement of the leg unit 4, a leg opening 65a extending downward from its upper edge is provided on the front sealing plate 65, and the leg movement module moves in the front-to-rear direction of the furniture assembly through the leg opening 65a when the leg unit 4 is switched between the retracted position and the stretched position. As shown in FIG. 17, the furniture assembly is in the sitting position, in which the leg unit 4 is in the retracted position, whereby the leg enclosing part 66 is generally accommodated in an interior space surrounded by the armrest 61 and the front sealing plate 65, with the footrest plate 43 and the footrest 64 attached thereto protruding from the leg opening 65a and snugly covering the front sealing plate 65. As shown in FIG. 18, the furniture assembly is in the lying position, where the leg unit 4 is in the stretched position and the backrest unit and the seat unit are in the reclined position, whereby the leg enclosing part 66 protrudes from the leg opening 65a. Since the leg enclosing part 66 at least partially encloses the leg unit 4, the moving parts of the leg unit 4 are barely visible from the outside, in particular the leg slider 42 and the guide rail 40a.

[0098]A ratio of a width D1 of the leg opening 65a to a width D2 of the front sealing plate 65 is not more than 0.6. A ratio of a height H1 of the leg opening 65a to a height H2 of the front sealing plate 65 is not more than 0.5. A height H2 of the front sealing plate 65 is not more than 280 mm. As a result, the leg unit 4 is narrowly constructed to form a compact structure.