Mechanical stretching device for electric seat

Abstract

The utility model relates to an electric seat mechanical stretching device which comprises two mechanical stretching units arranged in a bilateral symmetry mode, each mechanical stretching unit is composed of a seat frame supporting piece, a leg and foot assembly, a backrest rod and a transmission rod, the two mechanical stretching units are connected through a fixing assembly and a driving rod, and the leg and foot assemblies are installed on the seat frame supporting pieces. The chair is characterized in that the driving rod is composed of a first driving rod and a second driving rod, the seat frame supporting piece, the transmission rod, the upper half section of the second leg connecting rod and the lower half section of the backrest rod form a quadrilateral supporting structure of the chair, and the distance between the highest position of the foot rest and the heart of a user is increased by 80-120 mm when the user lies on the chair. The structure is simple, production, installation and maintenance are convenient, cost is low, comfort is improved, and overall stability is good.

Description

Technical Field

[0001] The present application relates to a mechanical extension device for an electric seat, which is mainly applicable to the design and production of electric seats with adjustable posture. Background Art

[0002] Refer to the patent document with application number CN201920005867.4 and patent name "Footrest assembly and mechanical extension device of sofa chair", which has two defects: 1. The structure is relatively complex, with more parts, relatively complex production and installation steps, and large material consumption, which increases production and maintenance costs; 2. The height of the footrest is relatively low when lying down, causing the user's feet to be lower than the heart, and the blood return to the heart is relatively not smooth. Summary of the invention

[0003] The technical problem solved by the present application is to overcome the above-mentioned deficiencies in the prior art and to provide an electric seat mechanical extension device which has a simple structure, is easy to produce, install and maintain, has low cost, and has a higher footrest position in a lying position.

[0004] The technical solution adopted by the present application to solve the above-mentioned technical problems includes: an electric seat mechanical extension device, including two mechanical extension units arranged symmetrically on the left and right, each mechanical extension unit is composed of a seat frame support, a leg and foot assembly, a backrest rod, and a transmission rod, the two mechanical extension units are connected by a fixing assembly and a driving rod, and the leg and foot assembly is installed on the seat frame support, and its characteristic is that: the driving rod is composed of a driving rod one and a driving rod two, the seat frame support, the transmission rod, the upper half of the leg connecting rod two, and the lower half of the backrest rod constitute a quadrilateral support structure of the seat, the movement of the leg and foot assembly drives the movement of the quadrilateral support mechanism, thereby synchronously driving the movement of the backrest rod, and the distance between the highest position of the footrest and the user's heart in a lying position is 80 to 120 mm higher than that in the comparison document (referring to the same user lying on the device of the present application and the device of the comparison document for comparison), so that the feet can be raised to a height roughly close to or slightly higher than the user's heart, which helps the blood in the user's legs to return to the heart, relatively expands the adjustment range of the leg and foot assembly, and improves comfort.

[0005] The leg and foot assembly of the present application is provided with a leg and foot assembly limiter, which is used to limit the maximum deployment position and the maximum folded position of the leg and foot assembly. The backrest rod is provided with a backrest lying position limiter used to limit the maximum backward tilt angle of the backrest rod. The leg and foot assembly limiter and the backrest lying position limiter in the lying state simultaneously limit the maximum deployment position of the leg and foot assembly and the maximum backward tilt angle of the backrest rod. The present application realizes synchronous lying position limiter of the leg and foot assembly and the backrest rod by contacting the lying position limiter surface of the seat frame with the backrest lying position limiter of the backrest rod when lying, and the leg and foot assembly limiter contacts the four lying position limiter surfaces of the leg connecting rod, so as to achieve good overall stability.

[0006] The leg and foot assembly described in the present application is composed of only leg link one, leg link two, leg link three, leg link four and a footrest. A driving rod one is fixedly connected to leg link one, and a leg and foot assembly limit is set on leg link one. One end of leg link one is hinged to the seat frame support, and the other end of leg link one is hinged to one end of leg link three, and the other end of leg link three is hinged to one end of the footrest, and the other end of the footrest is hinged to one end of leg link four. A leg and foot assembly lying position limit surface is set on leg link four, and the leg and foot assembly lying position limit surface cooperates with the leg and foot assembly limit to limit the maximum unfolding position of the leg and foot assembly. The middle part of leg link four is hinged to leg link one, and the other end of leg link four is hinged to one end of leg link two, and the other end of leg link two is hinged to the seat frame support.

[0007] The leg connecting rod 4 is also provided with a leg-foot assembly sitting posture limiting surface, and the leg-foot assembly sitting posture limiting surface cooperates with the leg-foot assembly limiting surface to limit the maximum retracted position of the leg-foot assembly.

[0008] The present application also provides an electric push rod, the front end of which is hinged to the drive rod through a drive rod hinge shaft, and the rear end of the electric push rod is hinged to the fixed component through a fixed component hinge shaft. The angle between the center line of the electric push rod and the horizontal plane is between ±4.5 degrees. The driving force of the electric push rod is basically consistent with the expansion and contraction direction of the leg and foot assembly, which is relatively labor-saving and energy-saving.

[0009] In the lying position, the distance between the footrest and the installation surface is between 284 mm and 353 mm, and the angle between the backrest support surface and the horizontal plane is between 38 degrees and 31 degrees.

[0010] The angle between the upper plane of the seat frame and the horizontal plane is not greater than 5 degrees.

[0011] Compared with the prior art, the present invention has the following advantages and effects: simple structure, convenient production, installation and maintenance, low cost, improved comfort and good overall stability. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 It is a three-dimensional schematic diagram of a sitting posture of an embodiment of the present application.

[0013] Figure 2 It is a side schematic diagram of the sitting posture of an embodiment of the present application.

[0014] Figure 3 It is a three-dimensional schematic diagram of a lying position according to an embodiment of the present application.

[0015] Figure 4 It is a side schematic diagram of a lying position of an embodiment of the present application.

[0016] Figure 5 It is a schematic diagram of main parameters of the embodiment of the present application in a lying position.

[0017] In the figure:

[0018] Fixed component 1, fixed component hinge axis 11, mounting surface 12 of fixed component and seat base, drive rod 2, drive rod hinge axis 21, leg and foot component 3, leg connecting rod one 31, leg and foot component limit 311, leg connecting rod two 32, leg connecting rod three 33, leg connecting rod four 34, leg and foot component lying position limit surface 341, leg and foot component sitting position limit surface 342, footrest 35, seat frame support 4, seat frame lying position limit surface 41, seat frame upper plane 42, seat frame backrest hinge axis 45, seat frame leg connecting rod two hinge axis 432, backrest rod 5, backrest lying position limit 51, backrest support surface 52, backrest transmission rod hinge axis 56, transmission rod 6, transmission rod leg connecting rod two hinge axis 632, electric push rod 7, electric push rod center line 71, horizontal line X, distance H between footrest and mounting surface, angle α between backrest support surface and horizontal plane. DETAILED DESCRIPTION

[0019] The present application is further described in detail below with reference to the accompanying drawings and examples. The following examples are explanations of the present application and the present application is not limited to the following examples. Figure 2 The left side is the front and the right side is the back.

[0020] See also Figure 1 to Figure 4 The mechanical extension device of the electric seat in the embodiment of the present application includes two mechanical extension units with left-right symmetry, each mechanical extension unit is composed of a seat frame support 4, a leg-foot assembly 3, a backrest rod 5, and a transmission rod 6. The two mechanical extension units are connected through a fixed assembly 1 and a driving rod 2. One end of the electric push rod 7 is hinged on the fixed assembly 1, and the other end of the electric push rod is hinged with the driving rod 2 to drive the electric seat posture conversion. The driving rod 2 is hinged with the leg connecting rod 1 31 of the leg-foot assembly 3 to control the expansion or folding of the leg-foot assembly 3. The present application forms a quadrilateral support structure of the electric seat through the seat frame support 4, the transmission rod 6, the upper half of the leg connecting rod 2 32, and the lower half of the backrest rod 5, which saves the process flow, reduces the number of parts, simplifies the installation, maintenance and debugging steps, and relatively saves costs; when lying down, the distance between the highest position of the footrest 35 and the user's heart is raised by 80 to 120 mm compared with the reference document, so that the foot can be raised to a height roughly close to or slightly higher than the user's heart, which helps the user's leg blood return to the heart and relatively expands the adjustment range of the leg-foot assembly 3.

[0021] The leg and foot assembly 3 of the present application is provided with a leg and foot assembly limit 311, which is used to limit the maximum unfolded position (i.e. lying state) and the maximum retracted position (i.e. sitting state) of the leg and foot assembly 3, and the backrest rod 5 is provided with a backrest lying position limit 51 for limiting the maximum backward tilting angle of the backrest rod 5. The leg and foot assembly limit 311 and the backrest lying position limit 51 in the lying state respectively limit the leg and foot assembly 3 and the backrest rod 5 at the same time, and when in the lying state, the leg and foot assembly limit 311 contacts the four lying position limit surfaces 341 of the leg connecting rod, and the seat frame lying position limit surface 41 contacts the backrest lying position limit 51 of the backrest rod 5, so as to realize the synchronous lying position limitation of the leg and foot assembly 3 and the backrest rod 5, and the overall stability is good.

[0022] The leg-foot assembly 3 described in the present application is only composed of a leg connecting rod 1 31, a leg connecting rod 2 32, a leg connecting rod 33, a leg connecting rod 4 34, and a footrest 35. The driving rod 2 is fixedly connected to the leg connecting rod 1 31, a leg-foot assembly limiter 311 is arranged on the leg connecting rod 1 31, one end of the leg connecting rod 1 31 is hinged to the seat frame support 4, the other end of the leg connecting rod 1 31 is hinged to one end of the leg connecting rod 3 33, and the other end of the leg connecting rod 3 33 is hinged to one end of the footrest 35. The other end of the footrest 35 is hinged to one end of the leg link four 34, and the leg link four 34 is provided with a leg and foot assembly lying position limiting surface 341, and the leg and foot assembly lying position limiting surface 341 cooperates with the leg and foot assembly limit 311 to limit the maximum unfolding position of the leg and foot assembly, the middle part of the leg link four 34 is hinged to the leg link one 31, and the other end of the leg link four 34 is hinged to one end of the leg link two 32, and the other end of the leg link two 32 is hinged to the seat frame support 41.

[0023] The leg connecting rod 4 34 is also provided with a leg-foot assembly sitting posture limiting surface 342, and the leg-foot assembly sitting posture limiting surface 342 cooperates with the leg-foot assembly limit 311 to limit the maximum retracted position of the leg-foot assembly.

[0024] The front end of the electric push rod 7 of the present application is hinged to the drive rod 2 through the drive rod hinge shaft 21, and the rear end of the electric push rod 7 is hinged to the fixed component 1 through the fixed component hinge shaft 11. The height of the drive rod hinge shaft 21 is close to the height of the fixed component hinge shaft 11, so that the angle between the center line 71 of the electric push rod and the horizontal plane (assuming that the seat is flat and the mounting surface 12 is horizontal) is always close to 0 degrees when the electric seat changes from a sitting position to a lying position. As a special case, the angle between the center line 71 of the electric push rod and the horizontal plane is between ±4.5 degrees. The driving force of the electric push rod 7 is basically consistent with the expansion and contraction direction of the leg and foot assembly 3, which is relatively labor-saving and energy-saving.

[0025] See also Figure 5, assuming that the seat is laid flat and the mounting surface 12 is horizontal, the main parameter design of the embodiment of the present application is determined according to actual needs. Through the adjustment of the design parameters, the distance H between the footrest 35 and the mounting surface 12 in the lying state of the embodiment of the present application is between 284 mm and 353 mm, and the angle α between the backrest support surface 52 and the horizontal plane is between 38 degrees and 31 degrees. The angle between the plane 42 on the seat frame of the present application and the horizontal plane is not greater than 5 degrees (whether in the lying position or sitting position or in the process of changing from lying position to sitting position).

[0026] Any part not described in this application is prior art and will not be described in detail. Any simple deformation or combination of the technical features and technical solutions of this application should be considered to fall within the protection scope of this application.

Claims

1. A mechanical extension device for an electric seat, comprising two mechanical extension units arranged symmetrically on the left and right, each mechanical extension unit consisting of a seat frame support, a leg and foot assembly, a backrest rod, and a transmission rod, the two mechanical extension units are connected by a fixing assembly and a driving rod, and the leg and foot assembly is mounted on the seat frame support, wherein: The driving rod is composed of a driving rod 1 and a driving rod 2. The seat frame support, the transmission rod, the upper half of the leg connecting rod 2, and the lower half of the backrest rod constitute a quadrilateral supporting structure of the seat. When lying down, the distance between the highest position of the footrest and the user's heart is raised by 80 mm to 120 mm.

2. The electric seat mechanical extension device according to claim 1, characterized in that: The leg and foot assembly is provided with a leg and foot assembly limiter, which is used to limit the maximum extended position and the maximum retracted position of the leg and foot assembly. The backrest rod is provided with a backrest lying position limiter which is used to limit the maximum backward tilting angle of the backrest rod. The lying position leg and foot assembly limiter and the backrest lying position limiter simultaneously limit the maximum extended position of the leg and foot assembly and the maximum backward tilting angle of the backrest rod.

3. The electric seat mechanical extension device according to claim 2, characterized in that: The leg and foot assembly is composed of only leg link one, leg link two, leg link three, leg link four and a footrest. A driving rod one is fixedly connected to leg link one, and a leg and foot assembly limit is arranged on leg link one. One end of leg link one is hinged to a seat frame support, and the other end of leg link one is hinged to one end of leg link three, and the other end of leg link three is hinged to one end of a footrest, and the other end of the footrest is hinged to one end of leg link four. A leg and foot assembly lying position limit surface is arranged on leg link four, and the lying position limit surface of the leg and foot assembly cooperates with the leg and foot assembly limit to limit the maximum unfolding position of the leg and foot assembly. The middle part of leg link four is hinged to leg link one, and the other end of leg link four is hinged to one end of leg link two, and the other end of leg link two is hinged to the seat frame support.

4. The electric seat mechanical extension device according to claim 3 is characterized in that: The leg connecting rod 4 is also provided with a leg-foot assembly sitting posture limiting surface, and the leg-foot assembly sitting posture limiting surface cooperates with the leg-foot assembly limiting surface to limit the maximum retracted position of the leg-foot assembly.

5. The electric seat mechanical extension device according to claim 1, characterized in that: An electric push rod is also provided, the front end of which is hinged to the driving rod through a driving rod hinge shaft, the rear end of which is hinged to the fixing assembly through a fixing assembly hinge shaft, and the angle between the center line of the electric push rod and the horizontal plane is between ±4.5 degrees.

6. The electric seat mechanical extension device according to claim 1, characterized in that: In the lying position, the distance between the footrest and the installation surface is between 284 mm and 353 mm, and the angle between the backrest support surface and the horizontal plane is between 38 degrees and 31 degrees.

7. The electric seat mechanical extension device according to claim 1, characterized in that: The angle between the upper plane of the seat frame and the horizontal plane is not greater than 5 degrees.

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