Sofa backrest adjustable device

Abstract

The utility model relates to the technical field of sofas, in particular to a sofa backrest adjustable device which comprises a mounting shaft fixedly mounted between armrest seats and close to the rear end; a plurality of adjusting holes are formed in the circumferential outer wall of the mounting shaft; adjusting holes are distributed in the circumferential outer wall of the mounting shaft in an annular array mode, when the threaded rods rotate, the threaded rods are matched with the threaded holes of the connecting plates, rotary motion is converted into linear motion, and the connecting plates are pushed to move along the connecting rods. As the connecting plate is connected with the bearing plate, the adjusting rod at the bottom of the bearing plate ascends and descends along with the connecting plate, the bottom end of the adjusting rod is matched with the adjusting holes in different positions of the mounting shaft in an inserted mode, and therefore the backrest assembly is driven to rotate, backrest angle adjustment is achieved, and multi-angle adjustment of the backrest can be achieved in cooperation with the adjusting rod at the bottom of the bearing plate. The problem that users with different body types, sitting posture preferences and function requirements are difficult to meet is solved, and the comfortable experience of the users and the product applicability are remarkably improved.

Description

Technical Field

[0001] This utility model relates to the field of sofa technology, specifically to an adjustable sofa backrest device. Background Technology

[0002] Sofas, as an important component of modern homes, are widely used in living rooms, lounges, and other spaces. The backrest, a key component of a sofa, directly impacts the user's sitting and lying experience and comfort. As consumers increasingly value the quality of their home furnishings, they place higher demands on the aesthetics, ergonomic design, and durability of sofa backrests.

[0003] Utility model patent application number CN202022747963.1 discloses a comfortable, environmentally friendly, and antibacterial sofa. This sofa includes a backrest, two armrests, and a seat cushion. The bottom ends of the front sides of the backrest are fixedly connected to one side of each armrest. The seat cushion is fixedly installed between the two armrests, and the top of the seat cushion is fixedly connected to the bottom of a sterilization plate. Sofa cushions are laid on both ends of the top of the sterilization plate. Several drawers are fixedly installed on the front of the seat cushion. The sofa is made of memory foam. This utility model's comfortable, environmentally friendly, and antibacterial sofa, with its drawers, two grooves, and a storage plate, fully utilizes every space of the sofa, making it convenient for users to place items. The sterilization plate not only sterilizes and disinfects the sofa but also increases friction with the sofa cushions, preventing them from shifting. The ventilation plate prevents odors from lingering on the sofa.

[0004] While this comfortable, eco-friendly, and antibacterial sofa offers the advantage of convenient disinfection, its practical use has the following limitations: The backrest is fixedly installed between the two armrests, forming a stable structure through a fixed connection. This design means the backrest angle cannot be adjusted after installation, remaining fixed. Since different users have significantly different body types, posture preferences, and functional needs, this fixed-angle backrest cannot meet diverse usage requirements, resulting in users not achieving optimal comfort and reducing product applicability and user satisfaction. Therefore, we propose an adjustable sofa backrest device. Utility Model Content

[0005] The purpose of this invention is to provide an adjustable sofa backrest device to solve the problems mentioned in the background art.

[0006] To achieve the above objectives, this utility model provides the following technical solution:

[0007] An adjustable sofa backrest device includes a seat cushion with armrests fixed to both ends of the seat cushion, and further includes:

[0008] The mounting shaft is fixedly installed between the armrest seats near the rear end; multiple adjustment holes are provided on the outer circumference of the mounting shaft.

[0009] A backrest assembly is installed above a mounting shaft; it includes a first frame and a second frame fixed to the bottom of the first frame; the bottom of the first frame has a cavity, and the second frame has a shaft hole for rotatable connection with the mounting shaft.

[0010] Inside the cavity, a second fixing plate and a first fixing plate are fixed at the upper and lower sides respectively; a connecting plate and a bearing plate are respectively provided at the upper and lower sides of the first fixing plate; multiple adjusting rods are fixed at the bottom of the bearing plate, and the bottom end of the adjusting rod passes through the shaft hole and is inserted into the corresponding adjusting hole; a threaded hole is opened at the center of the connecting plate; connecting rods are fixed between the two ends of the connecting plate and the bearing plate; the connecting rods pass through the first fixing plate and are slidably connected to the first fixing plate; a threaded rod is threadedly connected to the threaded hole; the threaded rod passes through the second fixing plate and is rotatably connected to the second fixing plate.

[0011] The first and second frames are covered with a filling layer, and a fabric layer is provided outside the filling layer.

[0012] As a preferred technical solution of this utility model, the adjustment holes are arranged in a ring array on the outer circumference of the mounting shaft, and the included angle between two adjacent adjustment holes is 15°-30°; the depth of the adjustment hole is not less than 1.5 times the diameter of the adjustment rod.

[0013] This design ensures the connection strength between the adjustment rod and the adjustment hole, preventing loosening after the backrest is adjusted, and effectively improving the stability and reliability of the backrest angle adjustment.

[0014] As a preferred technical solution of this utility model, a first bevel gear is coaxially keyed to the top end of the threaded rod; a horizontal transmission shaft is provided on one side of the top end of the threaded rod, and a second bevel gear that meshes with the first bevel gear is coaxially keyed to the front end of the transmission shaft, and the rear end of the transmission shaft passes through the first skeleton, the filling layer and the fabric layer.

[0015] As a preferred technical solution of this utility model, the rear end of the transmission shaft is provided with a detachable rotating disk, and the outer wall of the rotating disk is provided with anti-slip grooves.

[0016] In both of these settings, rotating the turntable makes it easy to convert horizontal rotation into vertical rotation of the threaded rod, thus facilitating the operation of the backrest's tilt angle.

[0017] As a preferred technical solution of this utility model, a plug is coaxially fixed to the rear end of the transmission shaft, a threaded post is coaxially fixed to the front end of the plug, and a locking nut is threadedly connected to the threaded post; a slot is provided at the center of the rotating disk, the plug is inserted into the slot, and the locking nut is pressed against the rear end face of the rotating disk.

[0018] As a preferred technical solution of this utility model, the cross-sectional shape of both the insert and the slot is a regular hexagon, and the size of the insert is adapted to the size of the slot.

[0019] Of these two settings, this design facilitates the stable rotation of the drive shaft via the rotating disk, ensuring effective torque transmission during transmission; at the same time, this design also has the advantage of easy installation.

[0020] As a preferred technical solution of this utility model, the bearing plate and the adjusting rod are integrally formed structures, and both the bearing plate and the adjusting rod are made of aluminum alloy.

[0021] In this design, the one-piece molding process increases the connection strength between the support plate and the adjustment rod, thereby ensuring the overall stability of the backrest assembly.

[0022] As a preferred technical solution of this utility model, a bearing is provided at the rotatable connection between the threaded rod and the second fixed plate. The outer ring of the bearing is fixedly connected to the second fixed plate by bolts, and the inner ring is coaxially keyed to the threaded rod.

[0023] In this configuration, the bearing supports and facilitates the rotation of the threaded rod, ensuring its rotational stability and smoothness.

[0024] Compared with the prior art, the beneficial effects of this utility model are as follows:

[0025] 1. The backrest assembly features a ring-shaped array of adjustment holes on the outer circumference of the mounting shaft. When the threaded rod rotates, it engages with the threaded holes on the connecting plate, converting rotational motion into linear motion and propelling the connecting plate along the connecting rod. Since the connecting plate is connected to the support plate, the adjustment rod at the bottom of the support plate rises and falls accordingly, allowing its bottom end to engage with adjustment holes at different positions on the mounting shaft. This drives the backrest assembly to rotate, achieving backrest angle adjustment. Combined with the adjustment rod at the bottom of the support plate, multi-angle backrest adjustment is possible. This design solves the problem of traditional sofas having fixed backrest angles, making it difficult to meet the needs of users with different body types, posture preferences, and functional requirements, significantly improving user comfort and product applicability.

[0026] 2. By rotating the disc at the rear end of the drive shaft, the bevel gear and threaded rod can drive the bearing plate to move the adjusting rod. This design enables rapid adjustment of the backrest angle and has the advantage of simple operation. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of the overall structure of this utility model;

[0028] Figure 2 This is a partial exploded structural diagram of the present invention;

[0029] Figure 3 This is a cross-sectional view of the backrest assembly in this utility model;

[0030] Figure 4 This is one of the partial structural schematic diagrams of the backrest assembly in this utility model;

[0031] Figure 5 This is the second partial structural schematic diagram of the backrest assembly in this utility model;

[0032] Figure 6 This is a partial exploded structural diagram of the backrest assembly in this utility model;

[0033] In the picture:

[0034] 1. Seat cushion;

[0035] 2. Armrest seat;

[0036] 3. Mounting shaft; 30. Adjustment hole;

[0037] 4. Backrest assembly; 40. First frame; 400. Cavity; 41. Second frame; 42. Filling layer; 410. Shaft hole; 43. First fixing plate; 44. Bearing plate; 440. Adjusting rod; 45. Connecting plate; 450. Threaded hole; 451. Connecting rod; 46. Second fixing plate; 47. Threaded rod; 470. First bevel gear; 48. Drive shaft; 480. Second bevel gear; 481. Insert block; 482. Threaded column; 483. Locking nut; 49. Rotating disk; 490. Slot. Detailed Implementation

[0038] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0039] This embodiment provides a technical solution:

[0040] Please see Figures 1-2As shown, an adjustable sofa backrest device includes a seat cushion 1, with armrest seats 2 fixed at both ends of the seat cushion 1, and also includes a mounting shaft 3, which is fixedly installed between the armrest seats 2 near the rear end. The mounting shaft 3 can be fixedly connected to the armrest seats 2 by bolts. The outer circumference of the mounting shaft 3 is provided with a plurality of adjustment holes 30.

[0041] Please see Figure 2 As shown, in this embodiment, the adjustment holes 30 are arranged in a ring array on the outer circumference of the mounting shaft 3, and the included angle between two adjacent adjustment holes 30 is 15°-30°; the depth of the adjustment hole 30 is not less than 1.5 times the diameter of the adjustment rod 440. This design allows for a rich and precise range of backrest angle adjustment positions, ensures the connection strength between the adjustment rod 440 and the adjustment hole 30, prevents loosening after backrest adjustment, and effectively improves the stability and reliability of backrest angle adjustment.

[0042] Please see Figures 3-5 As shown, the backrest assembly 4 is installed above the mounting shaft 3; it includes a first frame 40 and a second frame 41 fixed to the bottom of the first frame 40, which are fixedly connected by bolts; the bottom of the first frame 40 has a cavity 400, and the second frame 41 has a shaft hole 410 for rotatable connection with the mounting shaft 3; a second fixing plate 46 and a first fixing plate 43 are fixed to the upper and lower sides of the cavity 400, respectively, and the second fixing plate 46 and the first fixing plate 43 are bolted to the first frame 40; the upper and lower sides of the first fixing plate 43 are respectively provided with a connecting plate 45 and a bearing plate 44, and the bottom of the bearing plate 44 is fixed with multiple adjustment... The bottom end of the adjustment rod 440 passes through the shaft hole 410 and is engaged with the corresponding adjustment hole 30; a threaded hole 450 is provided at the center of the connecting plate 45; a connecting rod 451 is fixed between the two ends of the connecting plate 45 and the bearing plate 44; the connecting rod 451 is fixedly connected to the connecting plate 45 and the bearing plate 44 by bolts; the connecting rod 451 passes through the first fixing plate 43 and is slidably connected to the first fixing plate 43; a threaded rod 47 is threadedly connected to the threaded hole 450; the threaded rod 47 passes through the second fixing plate 46 and is rotatably connected to the second fixing plate 46; the outer parts of the first frame 40 and the second frame 41 are covered with a filling layer 42, and a fabric layer is provided on the outside of the filling layer 42.

[0043] With the above setup, the backrest angle can be adjusted by inserting the adjusting hole 30 on the mounting shaft 3 into the adjusting rod 440 in the backrest assembly 4. The transmission design of the threaded rod 47, connecting plate 45, and other structures ensures a stable adjustment process.

[0044] In this embodiment, the support plate 44 and the adjusting rod 440 are integrally formed structures, and both the support plate 44 and the adjusting rod 440 are made of aluminum alloy. The integral forming process increases the connection strength between the support plate 44 and the adjusting rod 440, thereby ensuring the overall stability of the backrest assembly 4; at the same time, the aluminum alloy material has both high strength and lightweight characteristics, which reduces the weight of the device while ensuring the supporting strength of the support plate 44 and the adjusting rod 440, making it easy to install and adjust, and it is not easy to rust, thus extending its service life.

[0045] In this embodiment, a bearing is provided at the rotatable connection between the threaded rod 47 and the second fixed plate 46. The outer ring of the bearing is fixedly connected to the second fixed plate 46 by bolts, and the inner ring is coaxially keyed to the threaded rod 47. This structure reduces the friction when the threaded rod 47 rotates, making the backrest adjustment operation smoother. At the same time, the support of the bearing enhances the stability of the rotation of the threaded rod 47, reduces wear, and improves the long-term reliability of the device.

[0046] Understandably, the filling layer 42 is composed of multiple layers of sponge with different densities. The sponge near the second frame 41 has a higher density to provide support, while the outer sponge has a lower density to improve comfort. The filling layer 42 is bonded to the first frame 40 and the second frame 41 with environmentally friendly adhesive to ensure that the filling layer 42 will not shift during backrest adjustment.

[0047] Please see Figure 6 As shown, furthermore, a first bevel gear 470 is coaxially keyed to the top of the threaded rod 47; a horizontal transmission shaft 48 is provided on one side of the top of the threaded rod 47, and a second bevel gear 480 meshing with the first bevel gear 470 is coaxially keyed to the front end of the transmission shaft 48; the rear end of the transmission shaft 48 passes through the first frame 40, the filling layer 42, and the fabric layer. This structure converts horizontal rotation into vertical rotational motion of the threaded rod 47, enabling remote backrest adjustment, and features high transmission efficiency, strong stability, and convenient user adjustment of the backrest angle. A detachable rotating disk 49 is provided at the rear end of the transmission shaft 48, and anti-slip grooves are provided on the outer wall of the rotating disk 49. The detachable design facilitates the assembly of the rotating disk 49, and the anti-slip grooves increase friction during operation, making the user's rotation operation more effortless and stable, thus optimizing the user's experience in adjusting the backrest angle. A plug block 481 is coaxially fixed to the rear end of the drive shaft 48, and a threaded post 482 is coaxially fixed to the front end of the plug block 481. A locking nut 483 is threadedly connected to the threaded post 482. A slot 490 is provided at the center of the rotating disk 49, and the plug block 481 is inserted into the slot 490. The locking nut 483 is pressed against the rear end face of the rotating disk 49. The design of the plug block 481 and the slot 490 ensures effective torque transmission during transmission, while also facilitating installation and disassembly, and ensuring a firm and reliable connection between the rotating disk 49 and the drive shaft 48.

[0048] In this embodiment, both the insert 481 and the slot 490 have a regular hexagonal cross-sectional shape, and the size of the insert 481 matches the size of the slot 490. This design prevents relative rotation between the rotating disk 49 and the drive shaft 48, ensuring that the rotational power of the rotating disk 49 is accurately transmitted to the drive shaft 48, thereby achieving accurate backrest angle adjustment.

[0049] In practical use, firstly, the user rotates the rotating disk 49 at the rear end of the drive shaft 48. The rotating disk 49 drives the drive shaft 48 to rotate via the insert block 481, and the drive shaft 48 drives the second bevel gear 480 to rotate. Since the second bevel gear 480 at the front end of the drive shaft 48 meshes with the first bevel gear 470 at the top end of the threaded rod 47, the first bevel gear 470 rotates and drives the threaded rod 47 to rotate under the bearing support of the second fixed plate 46. Since the threaded rod 47 engages with the threaded hole 450, it pushes the connecting plate 45 to move upward. Next, due to the connection... Plate 45 and bearing plate 44 are fixed by connecting rod 451. Bearing plate 44 moves upward synchronously, driving the adjusting rod 440 at the bottom to move upward in the shaft hole 410 and eventually disengage from the shaft hole 410. At this time, the user can rotate the backrest assembly 4, and the shaft hole 410 rotates along the mounting shaft 3 to adjust the backrest angle. When the backrest assembly 4 rotates to the appropriate angle, the user rotates the rotating disk 49 in the opposite direction to make the adjusting rod 440 re-insert into the adjusting hole 30 at the corresponding position of the mounting shaft 3, thus locking the backrest angle and completing the backrest angle adjustment.

[0050] The foregoing has shown and described the basic principles, main features, and advantages of this utility model. Those skilled in the art should understand that this utility model is not limited to the above embodiments. The embodiments and descriptions in the specification are merely preferred examples and are not intended to limit the utility model. Various changes and modifications can be made to this utility model without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claimed utility model. The scope of protection of this utility model is defined by the appended claims and their equivalents.

Claims

1. An adjustable sofa backrest device, comprising a seat cushion (1), with armrests (2) fixed to both ends of the seat cushion (1), characterized in that, Also includes: The mounting shaft (3) is fixedly installed between the armrest seats (2) near the rear end; the outer circumference of the mounting shaft (3) is provided with multiple adjustment holes (30); Backrest assembly (4) is installed above the mounting shaft (3); it includes a first frame (40) and a second frame (41) fixed to the bottom of the first frame (40); the bottom of the first frame (40) is provided with a cavity (400), and the second frame (41) is provided with a shaft hole (410) that is rotatably connected to the mounting shaft (3); Inside the cavity (400), a second fixing plate (46) and a first fixing plate (43) are fixed at the upper and lower sides respectively. A connecting plate (45) and a bearing plate (44) are provided at the upper and lower sides respectively. Multiple adjusting rods (440) are fixed at the bottom of the bearing plate (44). The bottom end of the adjusting rod (440) passes through the shaft hole (410) and is inserted into the corresponding adjusting hole (30). A threaded hole (450) is opened at the center of the connecting plate (45). A connecting rod (451) is fixed between the two ends of the connecting plate (45) and the bearing plate (44). The connecting rod (451) passes through the first fixing plate (43) and is slidably connected to the first fixing plate (43). A threaded rod (47) is threadedly connected at the threaded hole (450). The threaded rod (47) passes through the second fixing plate (46) and is rotatably connected to the second fixing plate (46). The first frame (40) and the second frame (41) are covered with a filling layer (42), and the filling layer (42) is covered with a fabric layer.

2. The adjustable sofa backrest device according to claim 1, characterized in that: The adjustment holes (30) are arranged in a ring array on the outer circumference of the mounting shaft (3), and the included angle between two adjacent adjustment holes (30) is 15°-30°; the depth of the adjustment holes (30) is not less than 1.5 times the diameter of the adjustment rod (440).

3. The adjustable sofa backrest device according to claim 1, characterized in that: The top end of the threaded rod (47) is coaxially keyed with a first bevel gear (470); a horizontal drive shaft (48) is provided on one side of the top end of the threaded rod (47), and the front end of the drive shaft (48) is coaxially keyed with a second bevel gear (480) that meshes with the first bevel gear (470). The rear end of the drive shaft (48) passes through the first skeleton (40), the filling layer (42) and the fabric layer.

4. The adjustable sofa backrest device according to claim 3, characterized in that: The rear end of the drive shaft (48) is provided with a detachable rotating disk (49), and the outer wall of the rotating disk (49) is provided with anti-slip grooves.

5. The adjustable sofa backrest device according to claim 4, characterized in that: The rear end of the drive shaft (48) is coaxially fixed with a plug (481), and the front end of the plug (481) is coaxially fixed with a threaded post (482). A locking nut (483) is threadedly connected to the threaded post (482). A slot (490) is provided at the center of the rotating disk (49). The plug (481) is inserted into the slot (490), and the locking nut (483) is pressed against the rear end face of the rotating disk (49).

6. The adjustable sofa backrest device according to claim 5, characterized in that: The cross-sectional shape of both the insert (481) and the slot (490) is a regular hexagon, and the size of the insert (481) is adapted to the size of the slot (490).

7. The adjustable sofa backrest device according to claim 1, characterized in that: The bearing plate (44) and the adjusting rod (440) are integrally formed structures, and both the bearing plate (44) and the adjusting rod (440) are made of aluminum alloy.

8. The adjustable sofa backrest device according to claim 1, characterized in that: A bearing is provided at the rotatable connection between the threaded rod (47) and the second fixed plate (46). The outer ring of the bearing is fixedly connected to the second fixed plate (46) by bolts, and the inner ring is coaxially connected to the threaded rod (47) by a key.

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