Linkage structure of back plate and leg plate of electric bed
By introducing a pull push rod assembly into the linkage structure of the back plate and the leg plate of the electric bed, and directly using a linear actuator to top the back plate frame, the problem of high lift force when the back plate is initially lifted in the prior art is solved, and the problem of high lift force is realized. The cost savings and structural simplicity of electric beds.
Patent Information
- Application Number
- CN202421437706.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-06-21
- Publication Date
- 2025-02-25
- Estimated Expiration
- 2034-06-21
AI Technical Summary
The linkage structure of the back plate and leg plate of the existing electric bed requires a large lift force when the back plate is pushed up from the angle between zero, resulting in an increase in linear actuator power and high structural cost.
A linkage structure was designed in which the linear actuator directly tops the back plate frame. The back plate frame drives the leg plate frame to be lifted or flattened by pulling the push rod assembly, reducing the lifting demand in the initial stage and reducing the structure. complexity and cost.
By reducing the lift demand in the initial stage, the power of the linear actuator and the strength requirements of the connecting rod assembly are reduced, and the cost savings of the electric bed are achieved, while improving the simplicity and stability of the structure.
Smart Images
Figure 00000000_0000_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of beds, in particular to a linkage structure of a backboard and a legboard of an electric bed. Background Art
[0002] As people's quality of life improves, the functional requirements for beds are getting higher and higher. For example, before going to sleep, people generally hope to read, watch TV or use their mobile phones in a semi-reclining or sitting position. In order to prevent the human body in a sitting or semi-reclining position from moving toward the legs, the bed is generally designed so that the back panel swings up around its own hinge axis or rotation axis, and at the same time, the leg panel is also linked to swing up around its own hinge axis or rotation axis.
[0003] The backboard and legboard linkage structures of the prior art electric beds are of many types and have different structures, but they all have a common shortcoming: the initial stage of the backboard lifting up from the angle of zero and swinging upward around its own hinge axis requires a large lifting force, and the linkage structure of the prior art lifts the legboard at the same time from the beginning. Therefore, in order to adapt to the double lifting force required in the initial stage, the power of the linear actuator such as the electric push rod must be increased, and the strength of the connecting rod assembly such as the pull-push rod assembly, the backboard frame fixed with the backboard, and the legboard frame fixed with the legboard must be increased accordingly, which greatly increases the cost of the electric bed. In addition, the simplicity and stability of the linkage structure of the prior art still have room for improvement. Utility Model Content
[0004] The technical problem to be solved by the utility model is to provide a linkage structure of the backboard and the legboard of an electric bed which can relatively reduce the lifting force required in the initial stage when the backboard is lifted up from an angle of zero and swings upward around its own hinge axis, and which is relatively cost-saving.
[0005] The technical solution of the utility model is to provide a linkage structure of a backboard and a legboard of an electric bed, including a backboard frame hinged to the fixed bed frame of the electric bed and fixed with the backboard, a legboard frame hinged to the fixed bed frame and fixed with the legboard, and a linear actuator; one end of the linear actuator is hinged to the fixed bed frame, and the other end of the linear actuator is hinged to the backboard frame; the electric bed with the linkage structure of the backboard and the legboard also includes at least one group of pull-push rod assemblies: the backboard frame at the hinge with the fixed bed frame is hinged to one end of a pull-push rod of the pull-push rod assembly through a first linkage block, and the other end of the pull-push rod has a rotating structure that links with the backboard frame to lift or lay the legboard frame flat; one end of the pull-push rod and the first linkage block have a structure that when the linear actuator is extended, the backboard frame is first lifted and rotated around the hinge point of the fixed bed frame to rise by a predetermined angle, and then the pull-push rod is pulled to simultaneously lift the legboard frame: one end of the pull-push rod has an elongated through hole, and the first linkage block has a first hinge shaft that slides in the elongated through hole.
[0006] After adopting the above structure, the linkage structure of the backboard and the legboard of the electric bed of the utility model has the following advantages:
[0007] In the initial stage when the back panel is lifted up from an angle of zero and swings upward around its own hinge axis, the linear actuator directly pushes up the back panel frame and drives the back panel to swing upward around its own hinge axis and rise. At this time, the lower side of the back panel rotates and drives the first hinge axis on the first linkage block to move from back to front in the elongated through hole at one end of the push-pull rod. The push-pull rod is not pulled, and the rotating structure at the other end of the push-pull rod does not lift the leg panel frame. When the first hinge axis moves to the front end of the elongated through hole, the back panel swings upward and rises again, and the push-pull rod is also pulled at the same time, and the rotating structure at the other end of the push-pull rod also lifts the leg panel frame at the same time, so that the leg panel swings upward around its own hinge axis and rises, thereby realizing the linkage between the back panel and the leg panel.
[0008] In the initial stage when the backboard is lifted up from an angle of zero and swings upward around its own hinge axis, the linear actuator only needs to bear the load on the top of the backboard, and when it rises to a predetermined angle, it drives the leg boards to rise together, which relatively reduces the power of linear actuators such as electric push rods, and can relatively reduce the requirements for the strength and rigidity of connecting rod assemblies such as push rod assemblies, backboard frames with the backboard fixed, and leg board frames with the leg boards fixed. This relatively saves the purchase cost and use cost of the linear actuator, and also relatively saves the material cost of electric beds such as push rod assemblies, backboard frames and leg board frames.
[0009] Compared with the prior art, the linear actuator directly pushes the back plate frame, and the back plate frame is then linked with the leg plate through the pull-push rod assembly, and its structure is relatively simple and reliable.
[0010] Furthermore, the predetermined angle is 5°-15°. After adopting the above preferred angles, the defect of large initial lifting force requirement and increased cost is overcome, thereby relatively saving the cost of the electric bed, and the technical effect of the leg board linkage meets the actual use needs.
[0011] Furthermore, the rotating structure includes a second linkage block, which is an L-shaped block or a triangular block, the first end of which is hinged to the other end of the pull-push rod, the second end of which is hinged to the fixed bed frame, the third end of which has a roller that rolls with the bottom surface of the longitudinal rod of the leg board frame to lift or lay the leg board flat, and the first end, the second end and the third end of the second linkage block are not in a straight line. With the above structure, the rotating structure is simple, stable and reliable.
[0012] Further, the push-pull rod assembly is provided in two groups symmetrically on both sides of the linear actuator: one end of each of the two vertical rods of the backboard frame on both sides of the width of the backboard frame is hinged to each side frame vertical rod of the fixed bed frame. The first linkage blocks are all first U-shaped blocks with openings facing forward. The bottom plates of the first U-shaped blocks are fixed to their respective vertical rods of the backboard frame. Rotating first hinge shafts are fitted to the free ends of the two vertical plates of the first U-shaped blocks. The first hinge shafts are slidably fitted or rollably fitted in the respective long through holes of their respective push-pull rods, and axial limiting structures are provided at both ends of the first hinge shafts. After adopting the above structure, the symmetry, balance, stability and mechanical properties of the linkage structure are better. On the premise of relatively saving the cost of the electric bed, the lifting or lowering of the backboard and the leg board are flexible, stable and reliable.
[0013] Further, the linkage structure of the backboard and the leg board of the electric bed of the present utility model further includes a rotating structure support pipe fixed to the bottom surface of a side frame vertical rod of the fixed bed frame. The second end of the second linkage block is hinged to the rotating structure support pipe through a second hinge shaft. After adopting the above structure, the mechanical properties of the rotating structure are better, and the linkage lifting or lowering of the leg board is more flexible, more stable and more reliable.
[0014] Further, the fixed bed frame includes a middle cross bar and a seat board frame; the linkage structure of the backboard and the leg board of the electric bed of the present utility model further includes a linear actuator mounting seat fixed on the seat board frame. The linear actuator mounting seat is a U-shaped seat extending along the length direction and with an opening facing upward. The tail end of the linear actuator housing is hinged to the two vertical plates at the free end of the U-shaped seat through a third hinge shaft. The free end of the driving rod of the linear actuator is hinged to a second U-shaped block fixed on a cross bar of the backboard frame through a fourth hinge shaft. After adopting the above structure, the connection between the linear actuator and the fixed bed frame and the backboard is more flexible and more stable, its mechanical properties are better, and the lifting or lowering of the backboard is more flexible, more stable and more reliable.
[0015] Further, the linkage structure of the backboard and the leg board of the electric bed of the present utility model further includes a seat board fixed between the leg board frame and the backboard frame and fixed on the fixed bed frame. The leg board frame includes a thigh board frame fixed with a thigh board and a calf board frame fixed with a calf board. The thigh board frame and the calf board frame are hinged to each other. One side of the thigh board frame close to the seat board is hinged to the fixed bed frame. The other side of the calf board frame away from the thigh board frame is hinged to the fixed bed frame. The lifting of the leg board frame means lifting the thigh board frame around the hinge point with the fixed bed frame and driving the calf board frame to lift around the hinge point with the fixed frame through the hinged part. After adopting the above structure, the lifting and lowering of the leg board are more suitable for the actual needs of the user to sit, semi-recline or lie flat, making it more comfortable and with a better experience. Description of the Drawings
[0016] Figure 1It is a schematic diagram of the structure when the linkage structure is applied to an electric bed and the backboard frame with the backboard fixed thereon and the legboard frame with the legboard fixed thereon are in a flat state when the backboard frame and the legboard frame are in a flat state.
[0017] Figure 2 yes Figure 1 Schematic diagram of the enlarged structure of A.
[0018] Figure 3 yes Figure 1 A schematic diagram of the structure when the back plate frame with the back plate fixed thereon and the leg plate frame with the leg plates fixed thereon are in a jacked-up state as viewed from above.
[0019] Figure 4 yes Figure 3 Schematic diagram of the enlarged structure of B.
[0020] Figure 5 yes Figure 3 Schematic diagram of the enlarged structure of C in the figure.
[0021] Figure 6 yes Figure 3 Schematic diagram of the enlarged structure of D in the figure.
[0022] Figure 7 yes Figure 3 The front plan view of the structure of the back plate, seat plate, thigh plate and calf plate is omitted (the back plate is the front and the calf plate is the back).
[0023] Figure 8 yes Figure 7 Schematic diagram of the enlarged structure of E.
[0024] As shown in the figure:
[0025] 1. Frame column structure, 11. Fixed bed frame, 111. Frame longitudinal rod, 112. Frame transverse rod, 113. Middle transverse rod, 12. Backboard, 13. Backboard frame, 131. Backboard frame longitudinal rod, 132. Backboard frame transverse rod, 14. Thigh board, 15. Calf board, 16. Thigh board frame, 161. Thigh board frame longitudinal rod, 17. Calf board frame, 18. Column, 19. Seat board, 110. Seat board frame;
[0026] 2. Linear actuator assembly, 21. Linear actuator, 211. Housing, 212. Driving rod, 22. Linear actuator mounting seat, 23. Third hinge shaft, 24. Second U-shaped block, 25. Fourth hinge shaft;
[0027] 3. a pull-push rod assembly, 31. a pull-push rod, 311. an elongated through hole, 32. a rotating structure, 321. a second linkage block, 3211. a top plate, 322. a fifth hinge shaft, 323. a second hinge shaft, 324. a roller, 325. a sixth hinge shaft, 326. a rotating structure support tube;
[0028] 4. First linkage block assembly, 41. First linkage block, 42. First hinge shaft, 421. Shoulder, 422. Split pin. DETAILED DESCRIPTION
[0029] The specific implementation methods of the present invention are further described below in conjunction with the accompanying drawings. It should be noted that the description of these specific implementation methods is used to help understand the present invention, but does not constitute a limitation of the present invention. In addition, the technical features involved in each specific implementation method of the present invention described below can be combined with each other as long as they do not conflict with each other.
[0030] like Figure 1 , Figure 2 , Figure 3 , Figure 4 , Figure 5 , Figure 6 , Figure 7 and Figure 8 shown.
[0031] The linkage structure of the backboard and legboard of the electric bed of the utility model comprises a backboard frame 13 hinged to the fixed bed frame 11 of the electric bed and fixed with a backboard 12, a legboard frame hinged to the fixed bed frame 11 and fixed with a legboard, and a linear actuator 21. The fixed bed frame 11 comprises a frame, which is a rectangular frame with a length much greater than a width, and the frame comprises two frame longitudinal rods 111 and two frame cross rods 112. Generally, a plurality of columns 18 or bed legs are fixed on the two frame longitudinal rods 111. The fixed bed frame 11 may also include a middle cross rod 113 arranged in the middle of the frame length. The linear actuator 21 generally comprises a commercially available electric push rod, a commercially available electric cylinder or a commercially available cylinder. The linear actuator 21 is also called a linear drive. The linear actuator 21 comprises a housing 211 and a driving rod 212, such as an electric push rod generally comprises a motor, a housing and a push rod. The electric cylinder generally comprises a motor, a cylinder body and a push rod. The cylinder generally includes a cylinder body and a piston rod. The backboard frame 13 is hinged to the fixed bed frame 11 of the electric bed, and one end or the lower end of the backboard frame longitudinal rod 131 is hinged to the fixed bed frame 11 through a hinge shaft. The above is the prior art.
[0032] The inventive points of the utility model are as follows.
[0033] One end of the linear actuator 21 is hinged to the fixed bed frame 11, and the other end of the linear actuator 21 is hinged to the backboard frame 13. The linkage structure of the backboard and legboard of the electric bed of the utility model also includes at least one set of pull-push rod assembly 3: the backboard frame 13 at the hinged position with the fixed bed frame 11 is hinged to one end of a pull-push rod 31 of the pull-push rod assembly 3 through a first linkage block 4, and the other end of the pull-push rod 31 has a rotating structure 32 that moves with the backboard frame 13 to lift or lay flat the legboard frame such as the thigh board frame 16 described below. One end of the push-pull rod 31 and the first linkage block 41 have a structure that when the linear actuator 21 is extended, the backboard frame 13 is first lifted up to rotate around the hinge point of the fixed bed frame 11 such as the hinge shaft to rise to a predetermined angle, and then the push-pull rod 31 is pulled to simultaneously lift the leg board frame such as the thigh board frame 16: one end of the push-pull rod 31 has an elongated through hole 311, and the first linkage block 41 has a first hinge shaft 42 that slides in the elongated through hole 311. It is not difficult to understand that the push-pull rod 31 has both the function of pulling and the function of pushing. Generally speaking, it is pulled when pushing upward and pushed when flattening downward.
[0034] The predetermined angle is preferably 5°-15°.
[0035] The rotating structure 32 includes a second linkage block 321, which is an L-shaped block or a triangular block. The first end of the second linkage block 321 is hinged to the other end of the pull-push rod 31, such as hinged via the fifth hinge shaft 322. The second end of the second linkage block 321 is hinged to the fixed bed frame 11, such as hinged via the second hinge shaft 323 described below. The third end of the second linkage block 321 has a roller 324 that rolls with the bottom surface of the leg board frame, such as the thigh board frame longitudinal rod 161 described below, to lift or flatten the leg board, such as the thigh board 14 described below. The roller 324 can be hinged to the other end of the pull-push rod 31 via the sixth hinge shaft 325. The first end, the second end and the third end of the second linkage block 321 are not in a straight line.
[0036] The above paragraph can also be described from another angle: the second linkage block 321 is preferably an L-shaped block, the right angle point of the second linkage block 321 is hinged to the other end of the push-pull rod 31, such as via the fifth hinge 322, the lower end of the second linkage block 321 is hinged to the fixed bed frame 11, such as via the second hinge 323 described below, and the other end of the right angle side of the second linkage block 321 has a roller 324 that rolls with the bottom surface of a leg board frame such as the thigh board frame longitudinal rod 161 described below to lift or flatten a leg board such as the thigh board 14 described below, and the roller 324 can be hinged to the other end of the push-pull rod 31 via the sixth hinge 325.
[0037] The specific shape of the second linkage block 321 can be as follows: its side view shape can be L-shaped, and when viewed from above, it can be a C-shaped with the opening facing downwards, but there is no top plate at the rear end where the roller 324 is installed to leave a space for installing the sixth hinge shaft 325, and there is also no top plate at the hinge joint between the second linkage block 321 and the other end of the pull push rod 31 to leave a space for installing the hinge shaft. That is, there is only a top plate 3211 in the middle section of the length on the straight top edge of the second linkage block.
[0038] The linkage structure of the backrest and the leg rest of the electric bed of the present utility model further includes a rotating structure support tube 326 fixed to the bottom surface of a side frame longitudinal rod 111 of the fixed bed frame 11. The lower end of the second linkage block 321 is hinged to the rotating structure support tube 326 through a second hinge shaft 323.
[0039] The said pull push rod assembly 3 is two groups symmetrically arranged on both sides of the linear actuator 21: one ends of two backrest frame longitudinal rods 131 on both width sides of the backrest frame 13, such as the ends close to the fixed bed frame, are respectively hinged to the respective side frame longitudinal rods 111 of the fixed bed frame 11. The first linkage blocks 41 are all first C-shaped blocks with the openings facing forward. The bottom plates of the first C-shaped blocks are respectively fixed to the respective backrest frame longitudinal rods 131. Rotating first hinge shafts 42 are respectively fitted on the free ends of the two vertical plates of the first C-shaped blocks. The first hinge shafts 42 are respectively slidably fitted or rollingly fitted in the respective long through holes 311 of the respective pull push rods 31, and axial limiting structures are provided at both ends of the first hinge shafts 42. For example, one end is a shaft shoulder 421, also called a large head, and there is an open pin 422 at the other end. For the convenience of description, the first linkage block 41, the first hinge shaft 42, the shaft shoulder 421 and the open pin 422 are collectively referred to as the first linkage block assembly 4. It is not difficult to understand that the axial limiting of all hinge shafts in this linkage structure can adopt the structure of shaft shoulders and open pins.
[0040] Since the seat board frame 110 is fixed by using multiple bolts and nuts to be screwed in the middle section of the length of the border of the fixed bed frame 11 and is located above the middle cross bar 113, the seat board frame 110 can be regarded as a part of the fixed bed frame 11, such as a transverse reinforcing frame in the middle of the length. That is, it can be understood that the fixed bed frame 11 further includes the seat board frame 110. The linkage structure of the backrest board and the leg board of the electric bed of the present utility model further includes a linear actuator mounting seat 22 fixed on the fixed bed frame 11, such as fixed on the middle cross bar 113 and the seat board frame 110. The linear actuator mounting seat 22 is a U-shaped seat extending along the length direction and opening upward. The tail end of the housing 211 of the linear actuator 21, such as the housing of an electric push rod, is hinged to the two vertical plates at the free end of the U-shaped seat through a third hinge shaft 23. The free end of the driving rod 212 of the linear actuator 21, such as the push rod of an electric push rod, is hinged to a second U-shaped block 24 fixed on a backrest board frame cross bar 132 through a fourth hinge shaft 25. For the convenience of description, the above linear actuator 21, housing 211, driving rod 212, third hinge shaft 23, second U-shaped block 24 and fourth hinge shaft 25 can be collectively referred to as the linear actuator assembly 2. The middle cross bar 113 can also be called the intermediate cross bar.
[0041] The linkage structure of the backrest board and the leg board of the electric bed of the present utility model further includes a seat board 19 located between the leg board frame and the backrest board frame 13 and fixed on the fixed bed frame 11. The leg board frame includes a thigh board frame 16 fixed with a thigh board 14 and a calf board frame 17 fixed with a calf board 15. The thigh board frame 16 and the calf board frame 17 are hinged to each other. One side of the thigh board frame 16 close to the seat board 19 is hinged to the fixed bed frame 11, and the other side of the calf board frame 17 away from the thigh board frame 16 is hinged to the fixed bed frame 11. Lifting the leg board frame means lifting the thigh board frame 16 around the hinge point with the fixed bed frame 11 and driving the calf board frame 17 to lift around the hinge point with the fixed bed frame 11 through the hinged part. It is not difficult to understand that the fixed bed frame 11 here can specifically be the border 111. The hinge point with the fixed bed frame 11 refers to the hinge point between the thigh board frame 16 and the fixed bed frame 11, such as being hinged through a hinge shaft. The hinged part refers to the part where the thigh board frame 16 and the calf board frame 17 are hinged to each other through a hinge shaft.
[0042] From right to left or from front to back in the figure, there are the backboard frame 13 fixed with the backboard 12, the seat board 19 fixed to the fixed bed frame 11 via the seat board frame 110, the thigh board frame 16 fixed with the thigh board 14 and the calf board frame 17 fixed with the calf board 15. The figure shows that the backboard 12, the seat board 19, the thigh board 14 and the calf board 15 are all connected, but in actual application, the boards on the bed are separated from each other, and the joints are left with gaps for swinging around their own hinges or for rising or falling. The backboard 12 and the leg board are only connected to their own frames separately, such as the backboard 12 is connected to the backboard frame 13, the thigh board 14 is connected to the thigh frame 16, and the calf board 15 is connected to the calf frame 17, and they are respectively screwed and fixed to each other with countersunk screws. For the convenience of description, all the above boards, frames and columns 18 can be collectively referred to as the frame-plate-column structure 1. The seat board 19 is also called the seat board.
[0043] The other end of the right angle side of the second linkage block 321 is provided with a roller 324 which rolls with the bottom surface of the thigh frame longitudinal rod 161 of the leg frame, such as the thigh frame 16, to lift or flatten the leg frame, such as the thigh frame 14, and drives the calf frame 15 to flatten through the mutually hinged shaft. That is, the roller 324 rolls with the bottom surface of the longitudinal rod of the leg frame, which is actually the roller 324 rolling with the bottom surface of the thigh frame longitudinal rod 161 of the thigh frame 16.
[0044] It is not difficult to understand that a hinge connection can also be called a pivot connection or a rotating connection. A hinge axis can also be called a pivot axis or a rotating axis.
[0045] The above unmarked parts, structures or quantities are not shown in the drawings, and some parts are not marked in the drawings. The drawings are only for reference only. If there is any inconsistency between the drawings and the text description or between the drawings, the text description shall prevail.
[0046] The above description is only a preferred embodiment of the utility model and is not intended to limit the utility model. For those skilled in the art, the utility model may have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the utility model shall be included in the protection scope of the utility model.
Claims
1. A linkage structure of a backboard and a legboard of an electric bed, comprising a backboard frame hinged to a fixed bed frame of the electric bed and fixed with a backboard, a legboard frame hinged to the fixed bed frame and fixed with a legboard, and a linear actuator; characterized in that: One end of the linear actuator is hinged to the fixed bed frame, and the other end of the linear actuator is hinged to the backboard frame; it also includes at least one group of push-pull rod assemblies: the backboard frame at the hinge with the fixed bed frame is hinged to one end of a push-pull rod of the push-pull rod assembly via a first linkage block, and the other end of the push-pull rod has a rotating structure that lifts or lays down the leg board frame in conjunction with the backboard frame; one end of the push-pull rod and the first linkage block have a structure that, when the linear actuator is extended, first lifts the backboard frame and rotates it around the hinge point of the fixed bed frame to rise to a predetermined angle, and then pulls the push-pull rod to simultaneously lift the leg board frame: one end of the push-pull rod has an elongated through hole, and the first linkage block has a first hinge shaft that slides in the elongated through hole.
2. The linkage structure of the backboard and legboard of the electric bed according to claim 1, characterized in that: The predetermined angle is 5°-15°.
3. The linkage structure of the backboard and legboard of the electric bed according to claim 1, characterized in that: The rotating structure includes a second linkage block, which is an L-shaped block or a triangular block. The first end of the second linkage block is hinged to the other end of the pull-push rod, and the second end of the second linkage block is hinged to the fixed bed frame. The third end of the second linkage block has a roller that rolls with the bottom surface of the longitudinal rod of the leg board frame to lift or flatten the leg board, and the first end, second end and third end of the second linkage block are not in a straight line.
4. The linkage structure of the backboard and legboard of the electric bed according to claim 3 is characterized in that: The pull-push rod assembly is composed of two groups symmetrically arranged on both sides of the linear actuator: one end of the two backboard frame longitudinal rods on both sides of the width of the backboard frame are hinged to the respective side frame longitudinal rods of the fixed bed frame, the first linkage blocks are first U-shaped blocks with openings facing forward, the bottom plates of the first U-shaped blocks are fixed to the respective backboard frame longitudinal rods, the free ends of the two vertical plates of the first U-shaped blocks are rotatably fitted with first hinge shafts, the first hinge shafts are slidably fitted in the respective elongated through holes of the respective pull-push rods and both ends of the first hinge shafts have axial limiting structures.
5. The linkage structure of the backboard and legboard of the electric bed according to claim 3 is characterized in that: It also includes a rotating structure support tube fixed on the bottom surface of a frame longitudinal rod of the fixed bed frame, and the second end of the second linkage block is hinged to the rotating structure support tube via a second hinge shaft.
6. The linkage structure of the backboard and legboard of the electric bed according to claim 1, characterized in that: The fixed bed frame includes a middle cross bar and a seat frame; it also includes a linear actuator mounting seat fixed on the seat frame, the linear actuator mounting seat is a U-shaped seat extended along the length direction and with the opening facing upward, the tail end of the linear actuator housing and the two vertical plates at the free end of the U-shaped seat are hinged via a third hinge shaft, and the free end of the driving rod of the linear actuator is hinged to the second U-shaped block fixed on a cross bar of the back frame via a fourth hinge shaft.
7. The linkage structure of the backboard and legboard of the electric bed according to claim 1, characterized in that: It also includes a seat board located between the leg board frame and the back board frame and fixed on the fixed bed frame, the leg board frame includes a thigh board frame to which a thigh board is fixed and a calf board frame to which a calf board is fixed, the thigh board frame and the calf board frame are hinged to each other, the thigh board frame is hinged to the fixed bed frame on one side close to the seat board, and the calf board frame is hinged to the fixed bed frame on the other side away from the thigh board frame, and lifting the leg board frame refers to lifting the thigh board frame around the hinge point with the fixed bed frame and driving the calf board frame to lift up around the hinge point with the fixed frame through the mutual hinge.