Mechanical stretching unit for eliminating back rubbing feeling
By introducing the mechanical design of the first and second rocker in the electric sofa or electric leisure chair, the rotation point of the backrest connector dynamically changes, solving the back rubbing and squeezing problems of the backrest during the switching of the seated position to the lying position, and improving the comfort of use and the rotation angle of the backrest.
Patent Information
- Application Number
- CN202422396176.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-30
- Publication Date
- 2025-08-08
- Estimated Expiration
- 2034-09-30
AI Technical Summary
During the process of switching backrest from sitting to lying position, the backrest produces a relative movement of the backrest relative to the seat cushion, resulting in a back rubbing feeling and discomfort on the user's back, and the lower end of the backrest may squeeze the user forward.
A mechanical stretching unit is designed to eliminate the feeling of back rubbing. By setting the first rocker and the second rocker on the longitudinal rod, the backrest connector is rotatably connected to the first rocker. The second rocker drives the first rocker to rotate through the connecting rod, so that the rotation point of the backrest connector dynamically changes. The backrest moves forward and downward during the tilt process to fit the human back, solving the problem of back rubbing and running waist.
It effectively eliminates the back rubbing feeling and the squeezing problem of the lower end of the backrest, increases the maximum rotation angle of the backrest, making the user's lying position more ergonomic and improves the comfort of use.
Smart Images
Figure CN223195760U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the field of furniture, in particular to a mechanical stretching unit for eliminating the back-rubbing feeling. Background Art
[0002] As living standards continue to improve, people's demands for a comfortable lifestyle are becoming increasingly demanding. In our fast-paced, high-pressure lives, a comfortable sofa or lounge chair can significantly improve our quality of life. Currently available electric sofas and lounge chairs are driven by motors, allowing the footrest to be extended and retracted, and the backrest angle to be adjusted.
[0003] However, in the vast majority of electric sofas or electric leisure chairs on the market, the backrest moves backward relative to the seat cushion when the motor drives the switch from a sitting position to a lying position, resulting in a back-rubbing feeling. The backrest will pull up the clothes on the user's back, which is very uncomfortable. In the mechanical extension device used in this type of sofa, the movement of the backrest is often achieved through a set of four-bar linkage mechanisms, and the rotation point of the backrest relative to the seat cushion is fixed. While the backrest rotates backward to cause the back-rubbing feeling, the lower end of the backrest will also squeeze the user forward, further reducing the comfort of use. Summary of the Invention
[0004] In order to solve the above technical problems, the utility model provides a mechanical extension unit for eliminating the back-rubbing feeling, comprising a base, a seat connecting rod assembly, a backrest connecting rod assembly and a backrest connecting piece, the seat connecting rod assembly and the backrest connecting rod assembly are both selectively movably arranged on the base as a main body support and the two are linked; the backrest connecting piece is installed on the backrest connecting rod assembly and is used to install the backrest; the seat connecting rod assembly includes a longitudinal rod, the backrest connecting rod assembly includes a first rocker, a second rocker, a connecting rod and a first auxiliary rod, the two ends of the connecting rod are respectively rotatably connected to the first rocker and the second rocker, and the first rocker and the second rocker are connected The lower ends are rotatably connected to the longitudinal rod, the upper end of the first rocker is rotatably connected to the backrest connecting piece, and the upper end of the second rocker is rotatably connected to the backrest connecting piece through the first auxiliary rod. When the seat connecting rod assembly is linked with the backrest connecting rod assembly and the second rocker is rotated forward relative to the longitudinal rod, the connecting rod drives the first rocker to rotate relative to the longitudinal rod and drives the backrest connecting piece to move forward and downward, and the first auxiliary rod drives the backrest connecting piece to rotate backward relative to the first rocker, so that the backrest connecting piece tilts backward relative to the longitudinal rod and moves forward and downward at the same time; so as to achieve the problem of eliminating back rubbing, waist running and squeezing of the human waist that cannot be achieved by the four-bar linkage.
[0005] The technical solution of the present utility model is achieved as follows:
[0006] The backrest connecting member is provided with a plurality of connecting rods, and the connecting rods are connected with the backrest connecting member to form a plurality of connecting rods. The connecting rods are connected with the backrest connecting member to form a plurality of connecting rods. The connecting rods are connected with the backrest connecting member to form a plurality of connecting rods. The rocker is rotatably connected; the lower end of the first rocker is rotatably connected to the longitudinal rod, the upper end of the first rocker is rotatably connected to the backrest connecting piece, the second rocker is rotatably connected to the longitudinal rod and is linked with the backrest connecting piece; one end of the first auxiliary rod is rotatably connected to the backrest connecting piece, and the other end of the first auxiliary rod is rotatably connected to the second rocker, and the first auxiliary rod is configured to link the second rocker with the backrest connecting piece; the backrest connecting rod assembly is configured so that when the seat connecting rod assembly is linked with the backrest connecting rod assembly and the second rocker is rotated forward relative to the longitudinal rod, the connecting rod drives the first rocker to rotate relative to the longitudinal rod and drives the backrest connecting piece to move forward and downward, and the first auxiliary rod drives the backrest connecting piece to rotate backward relative to the first rocker, so that the backrest connecting piece tilts backward relative to the longitudinal rod while moving forward and downward.
[0007] The longitudinal rod is linked to the seat of the sofa or is used to install the seat of the sofa, so the relative movement of the backrest connecting member and the longitudinal rod reflects the relative movement of the backrest and the seat; in the existing mechanical extension unit, the first rocker does not exist, but an extension rod fixed to it extends upward on the longitudinal rod, and the backrest connecting member is rotatably connected to the extension rod. When the backrest connecting member moves, it only rotates backward relative to the longitudinal rod, which causes the problem of rubbing the back and waist; and the four-bar mechanism composed of the backrest connecting rod assembly in the existing mechanical extension unit has a fixed rotation point of the backrest connecting member on the extension rod, which causes the problem of the lower end of the backrest squeezing the user forward when the backrest tilts backward; in this solution, the backrest connecting member is rotatably connected to the first rocker, and the rotation point of the backrest connecting member is located at the upper end of the first rocker. The first rocker is rotatably connected to the longitudinal rod, and the second rocker drives the first rocker through the connecting rod. The rod rotates on the longitudinal rod; in the process of the backrest tilting backward, the second rocker drives the backrest connecting part to rotate backward on the first rocker on the one hand, and on the other hand, the upper end of the first rocker rotates forward and downward to make the rotation point of the backrest connecting part dynamically change accordingly, so that the backrest always fits the human back; in this process, the rotation point of the backrest connecting part moves forward and downward, and the backrest connecting part as a whole also moves forward and downward accordingly. Therefore, the backrest installed on the backrest connecting part not only tilts backward to make the user lie down in this process, but also moves in accordance with the back of the human body, wherein the forward movement can make the backrest close to the seat when falling backward, maintaining the relative position of the two, solving the problem of rubbing the back and waist caused by the backward movement of the backrest relative to the seat, and the downward movement can compensate for the tilting of the lower end of the backrest when rotating, and solves the problem of the backrest squeezing the user forward and upward, thereby increasing the comfort of use.
[0008] At the same time, the first rocker arm and the second rocker arm jointly drive the backrest connecting part to rotate and increase the maximum rotation angle of the backrest, so that the posture of the user when lying down is more ergonomic and more comfortable.
[0009] Preferably, a second auxiliary rod is rotatably mounted on the base, with its lower end rotatably connected to the base and its upper end rotatably connected to a second rocker arm. The second auxiliary rod is configured such that when the longitudinal rod moves relative to the base, the second rocker arm moves accordingly and rotates relative to the longitudinal rod under the constraint of the second auxiliary rod. The second auxiliary rod rotates forward and downward on the base. The rotation of the second auxiliary rod occurs in two stages. In the first stage, the second auxiliary rod primarily rotates forward, causing the second rocker arm to essentially not rotate on the longitudinal rod, but to move forward with the longitudinal rod. This first stage represents the sofa switching from a sitting position to a TV position, causing the backrest connector and backrest to move solely with the longitudinal rod. In the second stage, the second auxiliary rod primarily rotates downward, causing the second rocker arm to rotate forward on the longitudinal rod. This second stage represents the sofa switching from a TV position to a reclining position, causing the backrest to tilt backward.
[0010] Preferably, the second rocker includes a linkage portion and a drive portion, the linkage portion being connected to the drive portion at one end, the other end of the linkage portion being rotationally connected to the second auxiliary rod, and the other end of the drive portion being rotationally connected to the first auxiliary rod. The second rocker serves as the power input for the movement of the backrest linkage assembly and the backrest connector. The linkage portion is configured such that when the backrest connector tilts rearward, the linkage portion moves with the longitudinal rod relative to the base, driving the second auxiliary rod to rotate on the base. The second auxiliary rod in turn causes the linkage portion to rotate downward on the longitudinal rod, driving the drive portion to rotate forward and downward together. The drive portion is configured such that when the linkage portion drives the drive portion to rotate together, the drive portion drives the backrest connector to rotate via the first auxiliary rod.
[0011] Preferably, the second rocker is V-shaped, with the linkage portion and the drive portion forming an angle, and a corner formed at the connection between the two. The second rocker is rotatably connected to the longitudinal rod at this corner. The reason for the second rocker's V-shape is that the angle formed between the linkage portion and the drive portion results in that, while the linkage portion and the drive portion rotate together in the same direction, their ends follow different displacement paths due to rotation. The end of the linkage portion primarily cooperates with the second auxiliary rod to move downward, while the drive portion needs to drive the backrest and the first rocker, thus moving forward and downward, thereby limiting the movement path of the backrest.
[0012] Preferably, the connecting rod is rotatably connected to the middle of the first rocker arm and the second rocker arm, so that when the second rocker arm drives the first rocker arm to rotate, the rotation amplitude of the first rocker arm will not be too large, but will be kept within the range that can effectively improve the backrest comfort, thereby preventing the backrest from squeezing the back of the human body due to excessive forward rotation of the first rocker arm.
[0013] Preferably, a connecting plate extending backward is fixedly connected to the rear end of the backrest connecting member, and the connecting plate is rotatably connected to the first auxiliary rod. The existence of the connecting plate is to cooperate with the first auxiliary rod to limit the movement trajectory of the backrest connecting member.
[0014] Preferably, the seat linkage assembly further includes a swing assembly, the swing assembly being mounted on the base, the longitudinal rod being mounted on the swing assembly, the swing assembly being configured to connect to the sofa's linear actuator and to move under the action of the linear actuator; the swing assembly comprising a first swing arm group, a second swing arm group, and a third swing arm group, the first, second, and third swing arm groups being stacked one on top of the other; the first swing arm group being rotationally connected to the base and swinging back and forth relative to the base; the second swing arm group being rotationally connected to the first swing arm group and swinging back and forth relative to the first swing arm group; the third swing arm group being rotationally connected to the second swing arm group and swinging back and forth relative to the second swing arm group; the third swing arm group being rotationally connected to the longitudinal rod and driving the longitudinal rod to swing relative to the base; the longitudinal rod moving back and forth as the swing assembly swings back and forth, thereby driving the movement of the backrest linkage assembly. This solution enables the sofa to be placed against a wall without being pressed against the wall.
[0015] Preferably, the first swing link group includes a first swing link and a second swing link, the third swing link group includes a third swing link and a fourth swing link, and the second swing link group includes a fifth swing link, a sixth swing link and a first longitudinal link; the lower end of the first swing link and the lower end of the second swing link are rotatably connected to the base, the upper end of the first swing link is rotatably connected to the upper part of the fifth swing link, the upper end of the second swing link is rotatably connected to the upper part of the sixth swing link, the lower end of the fifth swing link and the lower end of the sixth swing link are rotatably connected to the first longitudinal link, and the lower end of the third swing link and the lower end of the fourth swing link are also rotatably connected to the first longitudinal link; the upper end of the third swing link and the upper end of the fourth swing link are both rotatably connected to the longitudinal link. Each set of swing links swings synchronously, so as to achieve stable forward and backward movement as a whole, and the longitudinal rod and the backrest connector can move accordingly; in conjunction with the second auxiliary rod and the second rocker, the backrest moves with the seat when the sitting position is switched to the TV position, and the backrest can tilt backward when the TV position is switched to the lying position; the swing of the three sets of swing links is independent of each other and superimposed on each other, that is, the movement of the three sets of swing links will not interfere with each other, and they can swing stably. After each group swings forward, their respective forward movement distances can be superimposed to maximize the gap between the backrest and the wall for the backrest to fall backward.
[0016] Preferably, a second longitudinal link rotatably connected to the fifth swing link is provided between the fifth swing link and the sixth swing link. The second longitudinal link is used to stabilize the movement of the sixth swing link and the fifth swing link and synchronize the movement of the fifth swing link and the sixth swing link.
[0017] Preferably, a linkage rod is further provided for rotational connection between the first swing link or the second swing link and the second longitudinal link. The second longitudinal link, the linkage rod, the fifth swing link or the sixth swing link, and the corresponding first swing link or the second swing link can form a four-bar linkage mechanism, which is used to link the first swing link group and the second swing link group, limiting the motion trajectories of the two swing link groups and ensuring stable motion along a predetermined trajectory.
[0018] The design starting point, concept and beneficial effects of the utility model using the above technical solution are:
[0019] The longitudinal rod is linked to the seat of the sofa or is used to install the seat of the sofa, so the relative movement of the backrest connector and the longitudinal rod reflects the relative movement of the backrest and the seat; in the existing mechanical extension unit, the first rocker does not exist, but an extension rod fixed to the longitudinal rod extends upward, and the backrest connector is rotatably connected to the extension rod. When the backrest connector moves, it only rotates backward relative to the longitudinal rod, thereby causing the problem of rubbing the back and waist; and the four-bar mechanism composed of the backrest connecting rod assembly in the existing mechanical extension unit, the rotation point of the backrest connector on the extension rod is fixed, so when the backrest tilts backward, it will cause the lower end of the backrest to press the user forward.
[0020] In this solution, the backrest connector is rotatably connected to the first rocker, and the rotation point of the backrest connector is located at the upper end of the first rocker. The first rocker is rotatably connected to the longitudinal rod, and the second rocker drives the first rocker to rotate on the longitudinal rod through the connecting rod. During the process of the backrest tilting backward, the second rocker drives the backrest connector to rotate backward on the first rocker, and on the other hand, the upper end of the first rocker rotates forward and downward so that the rotation point of the backrest connector changes dynamically, so that the backrest always fits the human back. During this process, the rotation point of the backrest connector moves forward and downward, and the backrest connector as a whole also moves forward and downward. Therefore, the backrest installed on the backrest connector not only tilts backward to allow the user to lie down, but also moves in accordance with the human back during this process. The forward movement can make the backrest close to the seat when tilting backward, maintaining the relative position of the two, thereby solving the problem of rubbing the back and waist caused by the backward movement of the backrest relative to the seat. The downward movement can compensate for the tilting of the lower end of the backrest when rotating, thereby solving the problem of the backrest squeezing the user forward and upward, thereby increasing user comfort.
[0021] At the same time, the first rocker arm and the second rocker arm jointly drive the backrest connecting part to rotate and increase the maximum rotation angle of the backrest, so that the posture of the user when lying down is more ergonomic and more comfortable. BRIEF DESCRIPTION OF THE DRAWINGS
[0022] Figure 1 Schematic diagram of the three-dimensional structure of the mechanical extension unit in a sitting state in an embodiment of the present invention;
[0023] Figure 2 This is a side view of the mechanical extension unit in the embodiment of the present invention in a sitting position. Figure 1 ;
[0024] Figure 3 This is a side view of the mechanical extension unit in the embodiment of the present invention in a sitting position. Figure 2 ;
[0025] Figure 4Schematic diagram of the three-dimensional structure of the mechanical extension unit in the embodiment of the present invention in the TV posture state;
[0026] Figure 5 The side view of the mechanical extension unit in the embodiment of the present invention in the TV posture state Figure 1 ;
[0027] Figure 6 The side view of the mechanical extension unit in the embodiment of the present invention in the TV posture state Figure 2 ;
[0028] Figure 7 This is a schematic diagram of the three-dimensional structure of the mechanical extension unit in a lying state in an embodiment of the present invention;
[0029] Figure 8 This is a side view of the mechanical extension unit in the embodiment of the present invention in the lying state. Figure 1 ;
[0030] Figure 9 This is a side view of the mechanical extension unit in the embodiment of the present invention in the lying state. Figure 2 .
[0031] The figures are marked as follows: base 1; backrest connector 2; longitudinal rod 3; first rocker 4; second rocker 5; linkage part 51; drive part 52; corner 53; connecting rod 6; first auxiliary rod 7; second auxiliary rod 8; connecting plate 9; footrest connector 10; footrest link assembly 11; seat connector 12; first swing link 13; second swing link 14; third swing link 15; fourth swing link 16; fifth swing link 17; sixth swing link 18; first longitudinal link 19; second longitudinal link 20; linkage rod 21. DETAILED DESCRIPTION
[0032] In order to more clearly understand the above-mentioned objectives, features and advantages of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be noted that the embodiments of the present application and the features therein can be combined with each other without conflict.
[0033] In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Therefore, the scope of protection of the present invention is not limited to the specific embodiments disclosed below.
[0034] In the description of the present invention, the terms "first", "second", "third", etc. are used for descriptive purposes only and should not be understood as indicating or implying relative importance.
[0035] The specific implementation of the utility model is as follows:
[0036] like Figure 1-9 As shown, the utility model provides a mechanical stretching unit for eliminating the back-rubbing feeling, comprising a base 1, a seat connecting rod assembly, a backrest connecting rod assembly and a backrest connecting member 2, the base 1 is configured as the main support of the mechanical stretching unit, the seat connecting rod assembly and the backrest connecting rod assembly are both selectively movably arranged on the base 1, and the seat connecting rod assembly is linked with the backrest connecting rod assembly, the backrest connecting member 2 is arranged on the backrest connecting rod assembly and moves with the movement of the backrest connecting rod assembly, and the backrest connecting member 2 is configured to connect the backrest; the seat connecting rod assembly includes a longitudinal rod 3 arranged longitudinally along the front-to-back direction, the backrest connecting rod assembly includes a first rocker arm 4, a second rocker arm 5, a connecting rod 6 and a first auxiliary rod 7, the first rocker arm 4 is located in front of the second rocker arm 5, the connecting rod 6 is longitudinally arranged along the front-to-back direction, and the front end of the connecting rod 6 is rotatably connected to the first rocker arm 4, and the rear end of the connecting rod 6 is rotatably connected to the first rocker arm 4 The two rockers 5 are rotatably connected; the lower end of the first rocker 4 is rotatably connected to the longitudinal rod 3, the upper end of the first rocker 4 is rotatably connected to the backrest connector 2, the second rocker 5 is rotatably connected to the longitudinal rod 3 and is linked with the backrest connector 2; one end of the first auxiliary rod 7 is rotatably connected to the backrest connector 2, and the other end of the first auxiliary rod 7 is rotatably connected to the second rocker 5, and the first auxiliary rod 7 is configured to link the second rocker 5 with the backrest connector 2; the backrest connecting rod assembly is configured so that when the seat connecting rod assembly is linked with the backrest connecting rod assembly and the second rocker 5 is rotated forward relative to the longitudinal rod 3, the connecting rod 6 drives the first rocker 4 to rotate relative to the longitudinal rod 3 and drives the backrest connector 2 to move forward and downward, and the first auxiliary rod 7 drives the backrest connector 2 to rotate backward relative to the first rocker 4, so that the backrest connector 2 tilts backward relative to the longitudinal rod 3 while moving forward and downward.
[0037] The longitudinal rod 3 is linked to the seat of the sofa or is used to install the seat of the sofa, so the relative movement of the backrest connector 2 and the longitudinal rod 3 reflects the relative movement of the backrest and the seat; in the existing mechanical extension unit, the first rocker arm 4 does not exist, but an extension rod fixed to it extends upward on the longitudinal rod 3, and the backrest connector 2 is rotatably connected to the extension rod. When the backrest connector 2 moves, it only has a backward rotation relative to the longitudinal rod 3, which causes the problem of rubbing the back and waist; and the four-bar mechanism composed of the backrest connecting rod assembly in the existing mechanical extension unit, the rotation point of the backrest connector 2 on the extension rod is fixed, so when the backrest tilts backward, it will cause the problem of the lower end of the backrest squeezing the user forward; in this solution, the backrest connector 2 is rotatably connected to the first rocker arm 4, and the rotation point of the backrest connector 2 is located at the upper end of the first rocker arm 4. The first rocker arm 4 is rotatably connected to the longitudinal rod 3, and the second rocker arm 5 is driven by the connecting rod 6 The first rocker arm 4 rotates on the longitudinal rod 3; in the process of the backrest tilting backward, the second rocker arm 5 drives the backrest connector 2 to rotate backward on the first rocker arm 4 on the one hand, and on the other hand, the upper end of the first rocker arm 4 rotates forward and downward to make the rotation point of the backrest connector 2 dynamically change accordingly, so that the backrest always fits the human back; in this process, the rotation point of the backrest connector 2 moves forward and downward, and the backrest connector 2 as a whole also moves forward and downward accordingly. Therefore, the backrest installed on the backrest connector 2 not only tilts backward to make the user lie down in this process, but also moves in accordance with the back of the human body, wherein the forward movement can make the backrest close to the seat when falling back, maintaining the relative position of the two, solving the problem of rubbing the back and waist caused by the backward movement of the backrest relative to the seat, and the downward movement can compensate for the tilting of the lower end of the backrest when rotating, and solves the problem of the backrest squeezing the user forward and upward, thereby increasing the comfort of use.
[0038] At the same time, the first rocker 4 and the second rocker 5 jointly drive the backrest connector 2 to rotate and increase the maximum rotation angle of the backrest, so that the user's posture when lying down is more ergonomic and more comfortable.
[0039] Further, if Figure 1 、 4 As shown in Figures 7, the mechanical extension unit has a sitting state, a TV state and a lying state, which respectively correspond to the state in which the sofa is for a normal sitting state, the state in which the sofa footrest is extended for a sitting state with the feet raised, and the state in which the sofa footrest is extended and the backrest is collapsed for a lying state.
[0040] like Figure 3 、 5As shown in Figures 1 and 8, a second auxiliary rod 8 is rotatably provided on the base 1, the lower end of the second auxiliary rod 8 is rotatably connected to the base 1, and the upper end of the second auxiliary rod 8 is rotatably connected to the second rocker 5; the second auxiliary rod 8 is configured so that when the longitudinal rod 3 moves relative to the base 1, the second rocker moves accordingly and rotates relative to the longitudinal rod 3 under the restriction of the second auxiliary rod 8; the second auxiliary rod 8 rotates forward and downward on the base 1, and the rotation of the second auxiliary rod 8 is divided into two stages. The first stage is when switching from the sitting posture to the TV posture. In the first stage, the second auxiliary rod 8 mainly rotates To rotate forward, the second rocker arm 5 basically does not rotate on the longitudinal rod 3, but moves forward together with the longitudinal rod 3, so that the backrest connector 2 and the backrest only move with the longitudinal rod 3. When the footrest is extended, the backrest does not fall back, and the user can lift his feet and sit on the sofa using the mechanical extension unit; when switching from the TV posture to the lying posture is the second stage, in the second stage, the second auxiliary rod 8 mainly rotates downward, causing the second rocking arm to rotate forward on the longitudinal rod 3, so that the backrest tilts backward, and the user can lie on the sofa using the mechanical extension unit.
[0041] The second rocker 5 is V-shaped, and the second rocker 5 includes a linkage portion 51 and a driving portion 52. The linkage portion 51 is connected to the driving portion 52 at one end, and the other end of the linkage portion 51 is rotatably connected to the second auxiliary rod 8, and the other end of the driving portion 52 is rotatably connected to the first auxiliary rod 7; there is an angle between the linkage portion 51 and the driving portion 52, and a corner 53 is formed with the connection between the two, and the second rocker 5 is rotatably connected to the longitudinal rod 3 at the corner 53; the second rocker 5 serves as the power input for the movement of the backrest connecting rod assembly and the backrest connecting member 2, and the linkage portion 51 is configured so that when the backrest connecting member 2 tilts backward, the linkage portion 51 moves with the longitudinal rod 3 relative to the base 1, and the linkage portion 51 drives the second auxiliary rod 8 to rotate on the base 1, and the second auxiliary The auxiliary rod 8 in turn causes the linkage part 51 to rotate downward on the longitudinal rod 3, and drives the driving part 52 to rotate forward and downward together; the driving part 52 is configured so that when the linkage part 51 drives the driving part 52 to rotate together, the driving part 52 drives the backrest connector 2 to rotate via the first auxiliary rod 7; the reason why the second rocker 5 is V-shaped is that an angle is formed between the linkage part 51 and the driving part 52, so that although the linkage part 51 and the driving part 52 have the same rotation direction when they rotate together, the displacement trajectories of the ends of the two are different due to the rotation. The end of the linkage part 51 mainly cooperates with the second auxiliary rod 8 to move downward, while the driving part 52 needs to drive the backrest and the first rocker 4 and therefore moves forward and downward, thereby limiting the movement trajectory of the backrest.
[0042] Furthermore, the connecting rod 6 is pivotally connected to the middle of the first rocker 4 and the second rocker 5. This ensures that when the second rocker 5 drives the first rocker 4 to rotate, the first rocker 4's rotation amplitude is limited to a certain extent, remaining within the range that effectively improves backrest comfort. This prevents the backrest from compressing the backrest due to excessive forward rotation of the first rocker 4. A rearwardly extending connecting plate 9 is fixedly connected to the rear end of the backrest connector 2 and pivotally connected to the first auxiliary rod 7. The connecting plate 9 cooperates with the first auxiliary rod 7 to limit the movement trajectory of the backrest connector 2.
[0043] The mechanical extension unit also includes a footrest connector 10 and a footrest link assembly 11. The footrest connector 10 is configured to install a footrest and is mounted on the footrest link assembly 11. The footrest link assembly 11 is rotatably mounted on the seat link assembly and is linked to the seat link assembly. The extension of the footrest is achieved through the movement of the footrest link assembly 11. The movement of the footrest is not the focus of this embodiment, so the structure of the footrest link assembly 11 is not described in detail in this embodiment. In this embodiment, the mechanical extension unit also includes a seat connector 12. The seat connector 12 is used to install the seat, and the seat connector 12 is mounted on the longitudinal rod 3. Therefore, when the sofa switches states, the seat will also move.
[0044] Specifically, the seat connecting rod assembly also includes a swing assembly, the swing assembly is arranged on the base 1, the longitudinal rod 3 is arranged on the swing assembly, and the swing assembly is configured to be connected to the linear actuator of the sofa and move under the action of the linear actuator; the swing assembly includes a first swing rod group, a second swing rod group and a third swing rod group, the first swing rod group, the second swing rod group and the third swing rod group are superimposed on each other, the first swing rod group is rotatably connected to the base 1 and swings back and forth relative to the base 1, the second swing rod group is rotatably connected to the first swing rod group and swings back and forth relative to the first swing rod group, the third swing rod group is rotatably connected to the second swing rod group and swings back and forth relative to the second The swing arm group swings back and forth, the third swing arm group is rotatably connected to the longitudinal rod 3 and drives the longitudinal rod 3 to swing relative to the base 1, and the longitudinal rod 3 moves back and forth as the swing assembly swings back and forth and drives the backrest connecting rod assembly to move; through this scheme, both the seat and back linkage can be achieved, and the zero-wall placement of the sofa can be achieved; in the process of switching from a sitting position to a lying position, the three swing assemblies all swing forward, causing the longitudinal rod 3 to continuously drive the backrest connector 2 to move forward, so that the backrest connector 2 is farther and farther away from the rear end of the mechanical extension unit, that is, the distance from the wall is getting larger and larger, so that the backrest connector 2 and the backrest will not touch the wall when lying back, thereby achieving zero-wall placement.
[0045] Further, if Figure 1 、 4As shown in Figure 7, the first swing link group includes a first swing link 13 and a second swing link 14, the third swing link group includes a third swing link 15 and a fourth swing link 16, and the second swing link group includes a fifth swing link 17, a sixth swing link 18 and a first longitudinal link 19; the lower end of the first swing link 13 and the lower end of the second swing link 14 are rotatably connected to the base 1, the upper end of the first swing link 13 is rotatably connected to the upper part of the fifth swing link 17, the upper end of the second swing link 14 is rotatably connected to the upper part of the sixth swing link 18, the lower end of the fifth swing link 17 and the lower end of the sixth swing link 18 are rotatably connected to the first longitudinal link 19, and the lower end of the third swing link 15 and the lower end of the fourth swing link 16 are also rotatably connected to the first longitudinal link 19 connection; the upper end of the third swing link 15 and the upper end of the fourth swing link 16 are both rotatably connected to the longitudinal rod 3; each set of swing links swings synchronously, so as to achieve stable forward and backward movement as a whole, and the longitudinal rod 3 and the backrest connector 2 can move accordingly; in conjunction with the second auxiliary rod 8 and the second rocker 5, the backrest moves with the seat when the sitting position is switched to the TV position, and the backrest can tilt backward when the TV position is switched to the lying position; the swinging of the three sets of swing links is independent of each other and superimposed on each other, that is, the movement of the three sets of swing links will not interfere with each other, and they can swing stably. After each group swings forward, their respective forward movement distances can be superimposed to maximize the gap between the backrest and the wall for the backrest to fall backward.
[0046] A second longitudinal link 20 is also provided between the fifth swing link 17 and the sixth swing link 18, and the second longitudinal link 20 is rotatably connected to the upper ends of the fifth swing link 17 and the sixth swing link 18; the second longitudinal link is used to stabilize the movement of the sixth swing link 18 and the fifth swing link 17, and to synchronize the movement of the fifth swing link 17 and the sixth swing link 18. Furthermore, a linkage rod 21 is rotatably connected between the first swing link 13 or the second swing link 14 and the second longitudinal link 20; the second longitudinal link, the linkage rod 21, the fifth swing link 17 or the sixth swing link 18 and the corresponding first swing link 13 or the second swing link 14 can constitute a four-bar linkage, and is used for the linkage of the first swing link group and the second swing link group, limiting the movement trajectory of the two swing link groups, so that the movement is stably carried out according to the preset trajectory; in this embodiment, the linkage rod 21 is arranged between the first swing link 13 and the second longitudinal link 20, and the two ends of the linkage rod 21 are respectively rotatably connected to the first swing link 13 and the second longitudinal link 20.
Claims
1. A mechanical stretching unit for eliminating the back-rubbing feeling, characterized in that: The seat frame comprises a base, a seat connecting rod assembly, a backrest connecting rod assembly and a backrest connecting piece, wherein the base is configured as the main body support of the mechanical extension unit, the seat connecting rod assembly and the backrest connecting rod assembly are both selectively movably arranged on the base, and the seat connecting rod assembly is linked with the backrest connecting rod assembly, the backrest connecting piece is arranged on the backrest connecting rod assembly and moves with the movement of the backrest connecting rod assembly, and the backrest connecting piece is configured to connect the backrest; the seat connecting rod assembly comprises a longitudinal rod longitudinally arranged along the front-to-back direction, the backrest connecting rod assembly comprises a first rocker arm, a second rocker arm, a connecting rod and a first auxiliary rod, the first rocker arm is located in front of the second rocker arm, the connecting rod is longitudinally arranged along the front-to-back direction, the front end portion of the connecting rod is rotatably connected to the first rocker arm, and the rear end portion of the connecting rod is rotatably connected to the second rocker arm; the The lower end of a rocker is rotatably connected to the longitudinal rod, the upper end of the first rocker is rotatably connected to the backrest connecting piece, and the second rocker is rotatably connected to the longitudinal rod and linked with the backrest connecting piece; one end of the first auxiliary rod is rotatably connected to the backrest connecting piece, and the other end of the first auxiliary rod is rotatably connected to the second rocker, and the first auxiliary rod is configured to link the second rocker with the backrest connecting piece; the backrest connecting rod assembly is configured so that when the seat connecting rod assembly is linked with the backrest connecting rod assembly and the second rocker is rotated forward relative to the longitudinal rod, the connecting rod drives the first rocker to rotate relative to the longitudinal rod and drives the backrest connecting piece to move forward and downward, and the first auxiliary rod drives the backrest connecting piece to rotate backward relative to the first rocker, so that the backrest connecting piece tilts backward relative to the longitudinal rod and moves forward and downward at the same time.
2. The mechanical stretching unit for eliminating the back-rubbing feeling according to claim 1, characterized in that: A second auxiliary rod is rotatably provided on the base, the lower end of the second auxiliary rod is rotatably connected to the base, and the upper end of the second auxiliary rod is rotatably connected to the second rocker arm; the second auxiliary rod is configured so that when the longitudinal rod moves relative to the base, the second rocker arm moves accordingly and rotates relative to the longitudinal rod under the restriction of the second auxiliary rod.
3. The mechanical stretching unit for eliminating the back-rubbing feeling according to claim 2, characterized in that: The second rocker includes a linkage part and a driving part. The linkage part is connected to the driving part at one end. The other end of the linkage part is rotationally connected to the second auxiliary rod. The other end of the driving part is rotationally connected to the first auxiliary rod.
4. The mechanical stretching unit for eliminating the back-rubbing feeling according to claim 3, characterized in that: The second rocker is V-shaped, with an included angle between the linkage portion and the driving portion and a corner formed at the connection between the two. The second rocker is rotatably connected to the longitudinal rod at the corner.
5. The mechanical stretching unit for eliminating the back-rubbing feeling according to claim 1, characterized in that: The connecting rod is rotatably connected to the middle parts of the first rocking arm and the second rocking arm.
6. The mechanical stretching unit for eliminating the back-rubbing feeling according to claim 1, characterized in that: A connecting plate extending backward is fixedly connected to the rear end of the backrest connecting piece, and the connecting plate is rotatably connected to the first auxiliary rod.