Mechanical stretching device for electric seat

Abstract

The invention relates to an electric seat mechanical stretching device which comprises two mechanical stretching units, a driving pipe assembly and a lifting assembly, each mechanical stretching unit comprises a seat mounting assembly, a leg driving assembly, a leg assembly and a backrest assembly, and the electric seat mechanical stretching device is characterized in that the driving device is composed of a leg driving motor, a backrest driving motor and a lifting driving motor; the leg driving assembly is composed of a first leg driver and a second leg driver, a leg driving pipe is fixed to one end of the first leg driver through a leg driving pipe side plate, the other end of the first leg driver is hinged to one end of the second leg driver, and the middle of the first leg driver is hinged to the seat mounting assembly through a first leg driver mounting shaft; the other end of the second leg driver is hinged to the leg assembly through a second leg driver driving shaft, and a leg driving motor is hinged between the lifting assembly and the leg driving pipe. And a brake device is further arranged, so that positioning or pushing is facilitated. The posture adjustment is fast and convenient, the reliability is high, and moving and positioning are convenient.

Description

Technical Field

[0001] The present application relates to a mechanical extension device for an electric seat, which is mainly suitable for the design of a mechanical extension device for an electric seat driven by three motors. Background Art

[0002] For the prior art, see the utility model patent publication document with patent number 202420258416.2 and patent name “Mechanical stretching device for the elderly”. Its main defects are: the leg drive motor in the reference document is responsible for the expansion and contraction of the legs and the conversion between the sitting position and the state of assisting the elderly to stand up, while the backrest drive motor is only responsible for the conversion between the backrest sitting position and the lying position, which makes the leg drive motor have too long a stroke, heavy burden, and easy to damage. In addition, the reference document also has the problem of being inconvenient to move or being able to move but inconvenient to position. Summary of the invention

[0003] The first technical problem that the present application solves is to overcome the above-mentioned first deficiency in the prior art and to provide an electric seat mechanical extension device in which the leg drive motor only drives the leg assembly; the further technical problem that the present application solves is to overcome the above-mentioned second deficiency in the prior art, and the entire device is convenient for movement and positioning.

[0004] The technical solution adopted by the present application to solve the above-mentioned first technical problem is: an electric seat mechanical extension device, including two mechanical extension units symmetrically arranged on the left and right, and a drive tube assembly and a lifting assembly connecting the two mechanical extension units, the drive tube assembly including a leg drive tube, each mechanical extension unit including a seat mounting assembly, a leg drive assembly, a leg assembly, and a backrest assembly, the lifting assembly is installed on the base device, the seat mounting assembly is installed on the lifting assembly, and the leg assembly is installed on the seat mounting assembly, wherein the driving device is composed of a leg drive motor, a backrest drive motor, and a lifting drive motor, and the backrest drive motor It is installed on the lifting assembly and connected to the backrest assembly, the lifting drive motor is installed on the base device and connected to the lifting assembly, the leg drive assembly is composed of leg drive one and leg drive two, the leg drive tube is fixed to one end of leg drive one through the leg drive tube side plate, the other end of leg drive one is hinged to one end of leg drive two, the middle part of leg drive one is hinged to the seat mounting assembly through the leg drive one mounting shaft, the other end of leg drive two is hinged to the leg assembly through the leg drive two driving shaft, one end of the leg drive motor is installed on the lifting assembly, and the other end of the leg drive motor is hinged to the leg drive tube through the leg drive shaft to drive the leg assembly to move. The present application converts the rotational power of the leg drive tube into the leg extension power through the two-link design of the leg drive assembly, drives the leg assembly to open or close, and simplifies the structure of the leg drive assembly; the leg drive motor is only used to adjust the leg movement, the stroke is shortened, and it is not easy to be damaged, which improves the reliability and service life of the present application.

[0005] The present application uses three motors to drive a certain posture adjustment respectively, so that the posture adjustment of the present application is relatively quick and convenient, thereby improving the user experience.

[0006] The lifting assembly described in the present application includes a lifting frame, a lifting link 1, and a lifting link 2. The two sides of the lifting frame are respectively hinged to one end of the lifting link 1 and one end of the lifting link 2 on the side, and the other end of the lifting link 1 and the other end of the lifting link 2 are respectively hinged to the base device on the side. One end of the lifting drive motor is hinged to the lifting frame through a lifting drive hinge shaft, and the other end of the lifting drive motor is hinged to the base device. The lifting drive motor of the present application directly drives the upper end of the lifting frame to move upward, and the driving efficiency is high.

[0007] The rear part of the seat installation assembly is installed on the lifting assembly through the seat rear support rod, and the front part of the seat installation assembly is placed on the lifting frame. The structure is simple and the support is relatively reliable and stable.

[0008] The tail of the backrest drive motor described in the present application is installed on the lifting assembly, and the backrest assembly includes a backrest mounting member, a backrest drive rod 1, and a backrest drive rod 2. The backrest mounting member is L-shaped as a whole, one end of the backrest mounting member is hinged to the seat mounting assembly, the other end of the backrest mounting member is hinged to one end of the backrest drive rod 1, the other end of the backrest drive rod 1 is hinged to one end of the backrest drive rod 2, the other end of the backrest drive rod 2 is hinged to the backrest drive tube, and the backrest drive tube is hinged to the head of the backrest drive motor.

[0009] The backrest mounting part has the same front and rear heights when it is in the maximum reclining adjustment position.

[0010] The technical solution adopted by the present application to solve the above-mentioned second technical problem is: the present application is also provided with a brake device, a pushing wheel is arranged under the base device, the brake device includes a control handle, a rear brake rod, a rear brake, a transmission plate, a front brake rod, and a front brake rod front suspension. The rear brake rod, the rear brake, the transmission plate, the front brake rod, the front brake, and the front brake rod front suspension are symmetrically arranged on both sides of the electric seat mechanical extension device, the control handle is installed at the rear end of the rear brake rod symmetrically arranged on both sides, the rear brake rod is provided with a rear brake rod groove for fitting the transmission plate control shaft, the front end of the rear brake rod is provided with a rear brake member, the rear brake is installed on the base device and cooperates with the rear brake member, the front end of the transmission plate is installed on the base device through a transmission plate articulated shaft, the transmission plate is hinged to the rear end of the front brake rod through the rear articulated shaft of the front brake rod, the front end of the front brake rod is articulated to the lower end of the front suspension of the front brake rod through the front articulated shaft of the front brake rod, the upper end of the front suspension of the front brake rod is hinged to the base device, the front brake member is arranged on the inner side of the front articulated shaft of the front brake rod, and the front brake is installed on the base device and cooperates with the front brake member.

[0011] The rear brake comprises a rear brake mounting shaft, a rear brake plate, and a rear brake torsion spring. The rear brake plate is mounted on a base device via the rear brake mounting shaft. The rear brake mounting shaft is sleeved with a rear brake torsion spring. The rear brake torsion spring enables the rear brake plate to be away from the rear pushing wheel when the brake is not applied.

[0012] The front brake comprises a front brake mounting shaft, a front brake plate, and a front brake torsion spring. The front brake plate is mounted on a base device via the front brake mounting shaft. The front brake torsion spring is mounted on the front brake mounting shaft. The front brake torsion spring enables the front brake plate to be away from the front pushing wheel when the brake is not applied.

[0013] The present application controls the movement of the rear brake lever through a control lever. When the rear brake lever is in a braking state, the rear brake lever drives the rear brake member to brake and press the rear brake plate, and the rear brake plate presses the rear pushing wheel, so that the rear pushing wheel cannot rotate; at the same time, the rear brake lever drives the transmission plate control axis of the transmission plate to move downward, drives the rear hinge axis of the front brake lever at the front end of the transmission plate to move forward, drives the front brake lever and the front hinge axis of the front brake lever to move forward, thereby making the front brake member installed on the front hinge axis of the front brake lever move forward and press the front brake plate downward, and the front brake plate presses the front pushing wheel downward, thereby realizing the overall braking action. When it is necessary to push the device of the present application, the control lever is lifted to drive the rear part of the rear brake lever and the rear part of the transmission plate to move upward, the rear brake member moves backward and disengages from the rear brake plate, the rear brake plate rotates around the rear brake mounting shaft under the action of the rear brake torsion spring and disengages from the rear pushing wheel, the rear hinged shaft of the front brake lever moves backward under the influence of the movement of the transmission plate, driving the front brake lever to move backward, causing the front brake member to move backward and disengage from the front brake plate, the front brake plate disengages from the front pushing wheel around the front brake mounting shaft under the action of the front brake torsion spring, thereby completely releasing the pushing wheels, so that the device of the present application can be pushed.

[0014] Compared with the prior art, the present application has the following advantages and effects: posture adjustment is relatively quick and convenient, reliability is high, and movement and positioning are convenient. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a three-dimensional schematic diagram of a sitting posture of an embodiment of the present application.

[0016] Figure 2 It is a schematic diagram of the inner side of the sitting posture of an embodiment of the present application.

[0017] Figure 3 It is a three-dimensional schematic diagram of the TV posture of an embodiment of the present application.

[0018] Figure 4 It is a schematic diagram of the inner side of the TV posture of an embodiment of the present application.

[0019] Figure 5 It is a three-dimensional schematic diagram of a lying position according to an embodiment of the present application.

[0020] Figure 6 It is a schematic diagram of the outside of the lying position (the backrest mounting part is completely tilted and laid flat) of the embodiment of the present application.

[0021] Figure 7 It is a three-dimensional schematic diagram of the assisted standing-up state of an embodiment of the present application.

[0022] Figure 8 It is a schematic diagram of the outer side of the assisted standing up state of an embodiment of the present application.

[0023] Fig. 9It is a schematic diagram of a three-dimensional state of the base device of an embodiment of the present application, and the brake structure is in a closed (braking) state at this time.

[0024] Fig.10 yes Fig. 9 Schematic diagram of the outside.

[0025] Fig.11 This is another three-dimensional schematic diagram of the base device of the embodiment of the present application, in which the brake structure is in an open state (no brake, and the entire device can be pushed).

[0026] Fig.12 yes Fig.11 Schematic diagram of the outside.

[0027] In the figure: base device 1, pushing wheel 11, front pushing wheel 111, rear pushing wheel 112, driving tube assembly 2, leg driving tube 21, leg driving tube side plate 211, backrest driving tube 22, lifting assembly 3, lifting frame 31, lifting link 1 32, lifting link 2 33, driving device 4, leg driving motor 41, leg driving shaft 411, backrest driving motor 42, lifting driving motor 43, lifting driving hinge shaft 431, seat mounting assembly 5, leg driving assembly 6, leg driving 1 61, leg driving 1 mounting shaft 611, leg driving 2 62, leg driving 2 driving shaft 621, leg assembly 7, leg connecting rod 1 71, leg connecting rod 2 72, leg connecting rod 3 73, leg connecting rod 4 74, footrest 7 5. Seat rear support rod 8. Backrest assembly 9. Backrest mounting part 91. Backrest driving rod 1 92. Backrest driving rod 2 93. Braking device 10. Control handle 101. Rear brake rod 102. Rear brake rod slot 1021. Rear brake member 1022. Rear brake 103. Rear brake mounting shaft 1031. Rear brake plate 1032. Rear brake torsion spring 1033. Transmission plate 104. Transmission plate articulation shaft 1041. Transmission plate control shaft 1042. Front brake rod 105. Front brake rod rear articulation shaft 1051. Front brake rod front articulation shaft 1052. Front brake member 1053. Front brake 106. Front brake mounting shaft 1061. Front brake plate 1062. Front brake torsion spring 1063. Front brake rod front suspension 107. DETAILED DESCRIPTION

[0028] The present application will be further described in detail below in conjunction with the accompanying drawings and through examples. The following examples are intended to explain the present application but the present application is not limited to the following examples. Figure 2 The middle left is the front and the middle right is the back.

[0029] See also Figures 1 to 12The mechanical extension device of the electric seat in the embodiment of the present application includes two mechanical extension units symmetrically arranged on the left and right, and a drive tube assembly 2 and a lifting assembly 3 connecting the two mechanical extension units. The drive tube assembly 2 includes a leg drive tube 21 and a backrest drive tube 22. Each mechanical extension unit includes a seat mounting assembly 5, a leg drive assembly 6, a leg assembly 7, and a backrest assembly 9. The lifting assembly 3 is installed on the base device 1, the seat mounting assembly 5 is installed on the lifting assembly 3, and the leg assembly 7 is installed on the seat mounting assembly 5. The design feature of the present application is that the drive device 4 is composed of a leg drive motor 41, a backrest drive motor 42, and a lifting drive motor 43. The backrest drive motor 42 is installed on the lifting assembly 3 and connected to the backrest assembly 9. The lifting drive motor 43 is installed on the base device 1 and connected to the lifting component 3. The leg drive component 6 is composed of a leg drive one 61 and a leg drive two 62. The leg drive tube 21 is fixed to one end of the leg drive one 61 through the leg drive tube side plate 211. The other end of the leg drive one 61 is hinged to one end of the leg drive two 62. The middle part of the leg drive one 61 is hinged to the seat mounting component 5 through the leg drive one mounting shaft 611. The other end of the leg drive two 62 is hinged to the leg connecting rod two 72 through the leg drive two driving shaft 621. One end of the leg drive motor 41 is installed on the lifting component 3. The other end of the leg drive motor 41 is hinged to the leg drive tube 21 through the leg drive shaft 411 to drive the leg component 7 of the prior art to move. The present application uses a two-link design of the leg drive assembly 6 to convert the rotational power of the leg drive tube 21 into leg extension and retraction power, driving the leg assembly 7 to open or close, thereby simplifying the structure of the leg drive assembly 6; the leg drive motor 41 is only used to adjust the leg movement, with a shortened stroke and is not easily damaged, thereby improving the reliability and service life of this embodiment.

[0030] The backrest drive motor 42 of the present application only controls the movement of the backrest assembly 7 and is consistent with the prior art, and the lifting drive motor 43 only controls the movement of the lifting assembly 3. Since the present embodiment uses three electric motors to drive a certain posture adjustment respectively, the posture adjustment of the present embodiment is relatively fast and convenient, which improves the user experience.

[0031] The lifting assembly 3 described in the present application includes a lifting frame 31, a lifting link 1 32, and a lifting link 2 33. The two sides of the lifting frame 31 are respectively hinged to one end of the lifting link 1 32 and one end of the lifting link 2 33 on this side, and the other end of the lifting link 1 32 and the other end of the lifting link 2 33 are respectively hinged to the base device 1 on this side. One end of the lifting drive motor 43 is hinged to the lifting frame 31 through a lifting drive hinge shaft 431, and the other end of the lifting drive motor 43 is hinged to the base device 1. The lifting drive motor 43 of the present application directly drives the upper end of the lifting frame 31 to move upward, and the driving efficiency is high.

[0032] The present application also provides a brake device 10, which includes a control handle 101, a rear brake rod 102, a rear brake 103, a transmission plate 104, a front brake rod 105, a front brake 106, and a front brake rod front suspension 107. The rear brake rod 102, the rear brake 103, the transmission plate 104, the front brake rod 105, the front brake 106, and the front brake rod front suspension 107 are symmetrically arranged on both sides of the electric seat mechanical extension device. The control handle 101 is installed at the rear end of the rear brake rod 102 symmetrically arranged on both sides. The rear brake rod 102 is provided with a rear brake rod groove for fitting the transmission plate control shaft 1042. 1021, a rear brake member 1022 is provided at the front end of the rear brake rod 102 for braking the rear brake 103; the front end of the transmission plate 104 is installed on the base device 1 through a transmission plate hinge shaft 1041, the transmission plate 104 is hinged to the rear end of the front brake rod 105 through a front brake rod rear hinge shaft 1051, the front end of the front brake rod 105 is hinged to the lower end of the front brake rod front suspension 107 through a front brake rod front hinge shaft 1052, the upper end of the front brake rod front suspension 107 is hinged to the base device 1, and a front brake member 1053 is provided on the inner side of the front brake rod front hinge shaft 1052 for braking the front brake 106.

[0033] The rear brake rod groove 1021 is a waist-shaped groove, which plays a control and guiding role for the transmission plate control shaft 1042.

[0034] The rear brake 103 includes a rear brake mounting shaft 1031, a rear brake plate 1032, and a rear brake torsion spring 1033. The rear brake plate 1032 is mounted on the base device 1 through the rear brake mounting shaft 1031. The rear brake torsion spring 1033 is mounted on the rear brake mounting shaft 1031. The rear brake torsion spring 1033 allows the rear brake plate 1032 to move away from the rear pushing wheel 112 when the brake is not applied. The rear brake member 1022 cooperates with the rear brake plate 1032.

[0035] The front brake 106 includes a front brake mounting shaft 1061, a front brake plate 1062, and a front brake torsion spring 1063. The front brake plate 1062 is mounted on the base device 1 through the front brake mounting shaft 1061. The front brake torsion spring 1063 is mounted on the front brake mounting shaft 1061. The front brake torsion spring 1063 enables the front brake plate 1062 to move away from the front pushing wheel 111 when the brake is not applied. The front brake member 1053 cooperates with the front brake plate 1062.

[0036] The present application uses the control rod 101 to control the movement of the rear brake lever 102. When the rear brake lever 102 is in the Fig. 9In the braking state shown (the control rod 101 is in the low position), the rear brake rod 102 drives the rear brake member 1022 to press the rear brake plate 1032, and the rear brake plate 1032 presses the rear pushing wheel 112, so that the rear pushing wheel 112 cannot rotate; at the same time, the rear brake rod 102 drives the transmission plate control shaft 1042 of the transmission plate 104 to move downward, drives the front brake rod rear hinge shaft 1051 at the front end of the transmission plate 104 to move forward, drives the front brake rod 105 and the front brake rod front hinge shaft 1052 to move forward, so that the front brake member 1053 installed on the front brake rod front hinge shaft 1052 moves forward and presses the front brake plate 1062 downward, and the front brake plate 1062 presses the front pushing wheel 111 downward, brakes the front pushing wheel 111, and realizes the overall braking action. When it is necessary to implement this embodiment, the control rod 101 is lifted, driving the rear portion of the rear brake rod 102 and the rear portion of the transmission plate 104 to move upward, and the rear brake member 1022 moves backward and disengages from the rear brake plate 1032. The rear brake plate 1032 rotates counterclockwise around the rear brake mounting shaft 1031 under the action of the rear brake torsion spring 1033 (see Fig.10 ) is out of contact with the rear pushing wheel 112, the rear hinged shaft 1051 of the front brake lever is moved backward under the influence of the action of the transmission plate 104, driving the front brake lever 105 to move backward, so that the front brake member 1053 moves backward and is out of contact with the front brake plate 1062, and the front brake plate 1062 is out of contact with the front pushing wheel 111 around the front brake mounting shaft 1061 under the action of the front brake torsion spring 1063, thereby completely releasing the pushing wheel 11, so that the present embodiment can be pushed.

[0037] The rear portion of the seat mounting assembly 5 described in the present application is mounted on the lifting frame 31 of the lifting assembly 3 through the seat rear support rod 8, and the front portion of the seat mounting assembly 5 is placed on the lifting frame 31. The structure is simple and the support is relatively reliable and stable.

[0038] The rear end of the backrest drive motor 42 of the present application is installed on the lifting component 3, and the backrest component 9 includes a backrest mounting member 91, a backrest drive rod 1 92, and a backrest drive rod 2 93. The backrest mounting member 91 is L-shaped as a whole, and one end of the backrest mounting member 91 (the top end of the L-shape) is hinged to the seat mounting component 5, and the other end of the backrest mounting member 91 (the short side end of the L-shape) is hinged to one end of the backrest drive rod 1 92, and the other end of the backrest drive rod 1 92 is hinged to one end of the backrest drive rod 2 93, and the other end of the backrest drive rod 2 93 is hinged to the backrest drive tube 22, and the backrest drive tube 22 is hinged to the head of the backrest drive motor 42. The backrest mounting member 91 (the long side of the L-shape) is in the maximum reclining position (see Figure 6 ) when the backrest is tilted down and the height is the same (that is, the backrest mounting member 91 is completely tilted down and laid flat), this special case is particularly suitable for beauty chairs.

[0039] The posture change process of the embodiment of the present application is as follows: See also Figures 1 to 4In this embodiment, when switching from a sitting posture to a TV posture, the user only needs to control the leg driving motor 41 to drive the leg driving tube 21 to rotate counterclockwise around the leg driving tube side plate mounting shaft 2112 (see Figure 2 ), the leg driving tube side plate hinge shaft 2111 moves upward and backward synchronously, thereby driving the other end of the leg driving 1 61 and the leg driving 2 62 to move forward, and the leg driving 2 62 drives the leg connecting rod 2 72 to swing forward, thereby opening the leg assembly 7; the change from TV posture to sitting posture is the reverse action of the above process, which will not be described in detail. Figure 4 , Figure 6 The user can control the backrest drive motor 42 to move at any time, so that the backrest drive tube 22 drives the backrest drive rod 2 93 and the backrest drive rod 1 92 to move, and drive the backrest mounting member 91 to tilt and adjust between the TV posture and the lying posture at will to achieve the tilting angle preferred by the user.

[0040] See also Figure 7 , Figure 8 When the present embodiment switches from the sitting position to the assisting standing position, the head of the lifting drive motor 43 moves forward, so that the lifting assembly 3 is lifted upward as a whole, thereby driving the seat mounting assembly 5 to lift up as a whole, and assisting the user to stand up. After the user stands up, the head of the lifting drive motor 4 is controlled to retract to the sitting position.

Claims

1. An electric seat mechanical extension device, comprising two mechanical extension units arranged symmetrically on the left and right, and a drive tube assembly and a lifting assembly connecting the two mechanical extension units, wherein the drive tube assembly comprises a leg drive tube, each mechanical extension unit comprises a seat mounting assembly, a leg drive assembly, a leg assembly, and a backrest assembly, the lifting assembly is mounted on a base device, the seat mounting assembly is mounted on the lifting assembly, and the leg assembly is mounted on the seat mounting assembly, wherein: The driving device is composed of a leg driving motor, a backrest driving motor and a lifting driving motor. The backrest driving motor is installed on the lifting assembly and connected to the backrest assembly. The lifting driving motor is installed on the base device and connected to the lifting assembly. The leg driving assembly is composed of leg driving one and leg driving two. The leg driving tube is fixed to one end of the leg driving one through the leg driving tube side plate, and the other end of the leg driving one is hinged to one end of the leg driving two. The middle part of the leg driving one is hinged to the seat mounting assembly through the leg driving one mounting shaft, and the other end of the leg driving two is hinged to the leg assembly through the leg driving two driving shaft. One end of the leg driving motor is installed on the lifting assembly, and the other end of the leg driving motor is hinged to the leg driving tube through the leg driving shaft.

2. The electric seat mechanical extension device according to claim 1, characterized in that: The lifting assembly includes a lifting frame, a lifting link 1, and a lifting link 2. The two sides of the lifting frame are respectively hinged to one end of the lifting link 1 and one end of the lifting link 2 on this side, the other end of the lifting link 1 and the other end of the lifting link 2 are respectively hinged to the base device on this side, one end of the lifting drive motor is hinged to the lifting frame through a lifting drive hinge shaft, and the other end of the lifting drive motor is hinged to the base device.

3. The electric seat mechanical extension device according to claim 2, characterized in that: The rear part of the seat installation assembly is installed on the lifting assembly through the seat rear support rod, and the front part of the seat installation assembly is placed on the lifting frame.

4. The electric seat mechanical extension device according to claim 1, characterized in that: One end of the backrest drive motor is installed on the lifting assembly, and the backrest assembly includes a backrest mounting member, a backrest drive rod 1, and a backrest drive rod 2. The backrest mounting member is L-shaped as a whole, one end of the backrest mounting member is hinged to the seat mounting assembly, the other end of the backrest mounting member is hinged to one end of the backrest drive rod 1, the other end of the backrest drive rod 1 is hinged to one end of the backrest drive rod 2, the other end of the backrest drive rod 2 is hinged to the backrest drive tube, and the backrest drive tube is hinged to the head of the backrest drive motor.

5. The electric seat mechanical extension device according to claim 1, characterized in that: The backrest mounting part has the same front and rear heights when it is in the maximum reclining adjustment position.

6. The electric seat mechanical extension device according to claim 1, characterized in that: A brake device is also provided, a pushing wheel is provided under the base device, the brake device comprises a control handle, a rear brake rod, a rear brake, a transmission plate, a front brake rod, and a front brake rod front suspension. The rear brake rod, rear brake, transmission plate, front brake rod, front brake, and front brake rod front suspension are symmetrically arranged on both sides of the electric seat mechanical extension device, the control handle is installed at the rear end of the rear brake rod symmetrically arranged on both sides, the rear brake rod is provided with a rear brake rod groove for fitting the transmission plate control shaft, a rear brake member is provided at the front end of the rear brake rod, the rear brake is installed on the base device and cooperates with the rear brake member, the front end of the transmission plate is installed on the base device through a transmission plate articulation shaft, the transmission plate is hinged to the rear end of the front brake rod through the rear articulation shaft of the front brake rod, the front end of the front brake rod is articulated to the lower end of the front suspension of the front brake rod through the front articulation shaft of the front brake rod, the upper end of the front suspension of the front brake rod is hinged to the base device, the front brake member is provided on the inner side of the front articulation shaft of the front brake rod, the front brake is installed on the base device and cooperates with the front brake member.

7. The electric seat mechanical extension device according to claim 6, characterized in that: The rear brake comprises a rear brake mounting shaft, a rear brake plate, and a rear brake torsion spring. The rear brake plate is mounted on a base device via the rear brake mounting shaft. The rear brake mounting shaft is sleeved with a rear brake torsion spring. The rear brake torsion spring enables the rear brake plate to be away from the rear pushing wheel when the brake is not applied.

8. The electric seat mechanical extension device according to claim 6, characterized in that: The front brake comprises a front brake mounting shaft, a front brake plate, and a front brake torsion spring. The front brake plate is mounted on a base device via the front brake mounting shaft. The front brake torsion spring is mounted on the front brake mounting shaft. The front brake torsion spring enables the front brake plate to be away from the front pushing wheel when the brake is not applied.

9. The electric seat mechanical extension device according to claim 6, characterized in that: The rear brake lever groove is a waist-shaped groove.

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