Movable shank backrest frame linkage mechanism with three-folding-rod rotating shaft and sliding groove

Abstract

A three-folding-rod rotating shaft sliding groove moving type shank backrest frame linkage mechanism comprises a base, a backrest and a shank frame are arranged on the base, the shank frame is hinged to one end of the backrest, a telescopic cylinder is further arranged on the base, one end of the telescopic cylinder is hinged to the base, and the other end of the telescopic cylinder is hinged to the base. One end of the linkage assembly is connected to the backrest, the other end of the linkage assembly is connected to the shank frame, and the linkage assembly drives the shank frame to synchronously ascend and descend when the backrest ascends and descends. The utility model has the beneficial effects that through the mechanical coupling effect of the linkage component, the backrest and the shank frame which originally need to be controlled by two independent driving units are integrated into a single driving system, so that the number of execution mechanisms and the control complexity are effectively reduced.

Description

Technical Field

[0001] The utility model relates to a linkage control mechanism, in particular to a linkage mechanism of a three-fold rod rotating shaft chute movable calf backrest frame. Background Art

[0002] In the mechanical structure of existing massage chairs, the backrest elevation angle adjustment mechanism and the calf rest lifting mechanism usually adopt independent drive systems for control. Specifically, for the backrest part, an electric push rod is arranged at the hinge point of the backrest support and the seat cushion skeleton. The two ends of the push rod are respectively connected to the bottom frame of the seat cushion and the middle part of the backrest support. The supine angle is adjusted by the telescopic movement of the push rod. For the calf rest part, an independent electric cylinder is arranged in parallel under the calf support plate. When the user activates the lifting function, the piston rod of the electric cylinder pushes the calf support plate to change the inclination angle along the guide rail. Both systems need to be configured with independent control modules. Instructions are sent separately through the separate buttons on the user operation panel. The control unit drives the corresponding motor to operate according to the instruction signal, and transmits the power through the reduction gearbox to the push rod actuator to complete the action. Although this structural solution can achieve the basic functions, there are obvious design redundancies.

[0003] In the prior art, the configuration of the dual drive system results in too high a complexity of the overall structure of the machine. The two independent electric cylinders respectively occupy the installation spaces in the backrest area and the calf rest area, which not only increases the overall weight of the equipment, but also causes congestion in the wiring channels inside the skeleton. More critically, the asynchronous control of the two drive systems will cause motion interference during attitude adjustment. When the user adjusts the angles of the backrest and the calf rest simultaneously, due to the lack of a linkage coordination mechanism, the phenomenon of asynchronous movement is likely to occur, affecting the use comfort. In addition, the dual motor system increases the overall power consumption, and the probability of failure shows an exponential upward trend as the number of components increases. During later maintenance, the two systems need to be detected separately, significantly increasing the maintenance cost. This structural layout seriously restricts the lightweight development and space optimization design of massage chair products. Summary of the Utility Model

[0004] Aiming at the deficiencies of the prior art, the utility model provides a linkage mechanism of a three-fold rod rotating shaft chute movable calf backrest frame that realizes the linkage control of the backrest and the calf rest through a single telescopic cylinder.

[0005] To achieve the above object, the technical solution of the utility model is as follows: A linkage mechanism of a three-fold rod rotating shaft chute movable calf backrest frame, including a base, a backrest and a calf rest are arranged on the base. The calf rest is hinged to one end of the backrest. A telescopic cylinder is also arranged on the base. One end of the telescopic cylinder is hinged to the base, and the other end is hinged to the backrest to drive the backrest to lift when the telescopic cylinder expands and contracts. The linkage mechanism further includes a linkage component. One end of the linkage component is connected to the backrest, and the other end is connected to the calf rest to drive the calf rest to lift synchronously when the backrest lifts.

[0006] The beneficial effects of the present utility model are as follows: Through the mechanical coupling effect of the linkage component, the backrest and the calf support, which originally required two independent drive units for control, are integrated into a single drive system, effectively reducing the number of actuators and the control complexity. This design ensures the angular correlation between the backrest and the calf support during the lifting process through the motion transfer characteristics of the rigid rod, avoiding the problem of asynchronous actions that may occur in traditional multi-cylinder drives. As a preferred method, the linkage component can adopt a multi-rod linkage mechanism, which at least includes a set of parallelogram linkages. The linkage effect of the linkage system is triggered by the lifting displacement of the backrest, so that the calf support generates a displacement proportional to the backrest under the constraint of a specific trajectory. This structure not only achieves mechanical synchronization but also can adjust the lifting speed ratio of the backrest and the calf support through the optimized design of the rod length and the hinge point position to meet the usage requirements of users with different body types.

[0007] Further, a sliding arm is provided on the base, and a chute for the linkage component to slide therein is provided inside the sliding arm. The chute is inclined, and when the linkage component slides along the chute, the lifting of the backrest is synchronized with the lifting of the calf support.

[0008] The inclined chute converts the vertical lifting of the backrest into a composite motion with a specific direction component by restricting the motion trajectory of the linkage component, thereby precisely controlling the lifting amplitude of the calf support. The inclination angle of the chute and the hinge point position of the linkage component form a geometric constraint relationship to ensure that the swing angle of the calf support during the lifting of the backrest maintains a preset ratio with the inclination angle of the backrest. As a preferred method, the chute can be designed as a three-segment variable curvature structure, with a larger inclination angle in the initial segment to achieve a rapid response, a gentle transition in the middle segment to ensure the smoothness of the motion, and a reverse inclination in the final segment to provide a mechanical limit function, thereby optimizing the motion characteristics of the entire lifting process.

[0009] Further, the linkage component includes a rotating rod, a first support rod and a second support rod respectively hinged on both sides of the rotating rod. The other end of the first support rod is hinged on the base, and the other end of the second support rod is hinged on the calf support. A fixing member hinged on the backrest is provided on one side of the center of the rotating rod facing the backrest, and a pulley sliding in the chute is provided on the side facing the base.

[0010] This three-rod linkage mechanism decomposes the lifting displacement of the backrest into two orthogonal motion components through the pivotal motion of the rotating rod. The first support rod provides basic support and establishes a pivot point, and the second support rod transfers the rotational displacement to the calf support. The cooperation between the pulley and the chute not only ensures the accuracy of the motion trajectory but also reduces the motion resistance through rolling friction. As a preferred method, the rotating rod can be provided with an eccentric counterweight structure, and the center of mass position forms a specific offset with the center of the pulley. The gravity is used to compensate for the inertial impact when the backrest descends, and at the same time, the balance state of the rotating rod is automatically adjusted through the contact pressure between the pulley and the chute.

[0011] Furthermore, a support arm is provided on the base, and the support arm, the sliding arm and the base are connected to form a triangle, and the other end of the first support rod is hinged to the support arm.

[0012] The triangular frame structure significantly improves the bending stiffness and torsional resistance of the entire mechanism, especially when subjected to asymmetric loads, and can effectively disperse stress concentration. The support arm and the sliding arm form a stable spatial truss structure to ensure that the first support rod will not produce lateral deviation when transmitting torque. As a preferred method, the support arm can adopt a hollow tubular cross-section design, with cross reinforcement ribs inside and an array of weight-reducing holes on the outer surface, so as to achieve lightweight while ensuring structural strength. At the same time, the tubular structure can be used as a cable channel to improve the overall aesthetics of the equipment.

[0013] Furthermore, the hinged part between the second support rod and the calf frame is located relatively below the hinged part between the backrest and the calf frame.

[0014] This layout forms a two-stage lever transmission system, which amplifies the displacement output of the second support rod by changing the relative position of the fulcrum and the point of action. The lower hinge point design makes the lifting and lowering motion trajectory of the calf stand more compatible with the physiological curvature of the human body when adjusting the sitting posture. As a preferred method, an adjustable eccentric shaft structure can be set at the hinge, and the effective arm length can be changed by rotating the eccentric shaft, thereby fine-tuning the lifting and lowering range of the calf stand to adapt to the differences in calf lengths of different users.

[0015] Furthermore, the fixing piece is arranged to pass through both sides of the rotating rod, and the side facing the back is a hinged part with a smooth surface, and the side facing the base is a fixing part with a threaded surface. The pulley is fixed on the fixing part, and a fixing nut is arranged outside the fixing part to form a fixed connection between the fixing piece and the rotating rod.

[0016] This dual-function fixing part realizes the reliable connection between the rotating rod and the backrest and the rapid disassembly and assembly of the pulley assembly. The threaded matching structure allows the accurate adjustment of the preload of the pulley and the slideway. The through-type design ensures uniform load distribution and avoids stress concentration caused by unilateral force. As a preferred method, the fixing part can be provided with a stepped shaft structure, and the end can be processed with anti-loosening serrations, and matched with a fixing nut with an elastic washer, which can effectively prevent the thread from loosening while ensuring the connection strength.

[0017] Furthermore, a bearing plate is provided on the backrest, and the bearing plate is fixed to the opposite front side of the hinge between the telescopic cylinder and the backrest.

[0018] This safety redundancy design forms a mechanical stop when the hydraulic system fails, and establishes an emergency support structure through the contact between the bearing plate and the piston rod of the telescopic cylinder. The installation position of the bearing plate is calculated mechanically to ensure that it can effectively share the impact load under the maximum load condition. As an optimal method, the bearing plate can adopt a folding design. When working normally, it is retracted into the backrest interior, and when abnormal pressure is detected, it automatically pops out through a spring mechanism, which not only keeps the appearance tidy but also ensures the emergency braking function. Description of the Drawings

[0019] Figure 1 Isometric view of the embodiment of the present utility model;

[0020] Figure 2 Partial enlarged view of the linkage assembly of the embodiment of the present utility model;

[0021] Figure 3 Exploded view of the linkage assembly of the embodiment of the present utility model;

[0022] Figure 4 Partial enlarged view at the rotating rod of the embodiment of the present utility model;

[0023] Figure 5 Exploded view of the embodiment of the present utility model;

[0024] Figure 6 Side view of the embodiment of the present utility model in the state where the backrest and the calf support are lifted synchronously. Detailed Description of the Invention

[0025] A linkage mechanism of a three-fold rod rotating shaft sliding groove mobile calf backrest support of an embodiment of the present utility model is as Figures 1-6 shown: It includes a base 1, on which a backrest 2 and a calf support 3 are installed. Among them, the calf support 3 is connected to the end of the backrest 2 through a hinge shaft 31. A telescopic cylinder 4 is installed at the rear side of the base 1. The cylinder body end of the telescopic cylinder 4 is hinged to the base 1, and the piston rod end is hinged to the backrest 2. When the telescopic cylinder 4 expands and contracts, it can drive the backrest 2 to move up and down.

[0026] Sliding arms 11 are symmetrically arranged on both sides of the base 1, and an inclined chute 111 is provided inside each sliding arm 11. The linkage assembly 6 includes a rotating rod 61, and a first support rod 62 and a second support rod 63 are respectively hinged on both sides of the rotating rod 61. The end of the first support rod 62 is hinged on the support arm 12, and the support arm 12, the sliding arm 11 and the base 1 together form a triangular stable structure. The end of the second support rod 63 is hinged to the area below the calf support 3, and the hinge point position is lower than the hinge shaft 31 position of the calf support 3 and the backrest 2.

[0027] At the center of the rotating rod 61, there is a fixing member 64 passing through the rod body. The side facing away from the backrest 2 is a smooth hinge portion 641, which is hinged to the backrest 2; the side facing the base 1 is a threaded fixing portion 643, and a pulley 65 is fixed on the fixing portion 643. The fixing member 64 is locked on the fixing portion 643 by a fixing nut 66 to form a fixation with the rotating rod 61. The pulley 65 is embedded in the sliding groove 111 of the sliding arm 11 and can slide in the sliding groove 111. A bearing plate 21 is further provided on the front side of the backrest 2. The bearing plate 21 is located in front of the piston rod of the telescopic cylinder 4 and can abut against the piston rod to form a temporary support in case of equipment failure.

[0028] Working principle: When the telescopic cylinder 4 extends, it pushes the backrest 2 to rotate upward. At this time, the hinge portion 641 of the linkage assembly 6 rises with the backrest 2. The pulley 65 slides along the inclined sliding groove 111, driving the rotating rod 61 to generate a compound motion. The first support rod 62, under the fixed support of the support arm 12, transfers the displacement of the rotating rod 61 to the second support rod 63, and then drives the calf support 3 through the second support rod 63. Due to the inclined guiding action of the sliding groove 111 and the linkage of the three-link structure, the calf support 3 generates a synchronous upward movement around the hinge shaft 31. When the telescopic cylinder 4 contracts, each component moves in the reverse direction to achieve synchronous descent. The bearing plate 21 keeps a gap from the piston rod during normal operation and can contact the piston rod to form a mechanical limit when sudden pressure abnormality occurs.

[0029] The above embodiments are only one of the preferred specific embodiments of the present invention. Ordinary changes and substitutions made by those skilled in the art within the scope of the technical solution of the present invention are included in the protection scope of the present invention.

Claims

1. A three-folding rod rotating shaft slide movable calf backrest linkage mechanism, comprising a base, a backrest and a calf frame are arranged on the base, the calf frame is hinged to one end of the backrest, and a telescopic cylinder is also arranged on the base, one end of the telescopic cylinder is hinged to the base, and the other end is hinged to the backrest to drive the backrest to rise and fall when the telescopic cylinder is extended and retracted, characterized in that: The utility model also comprises a linkage component, one end of which is connected to the backrest, and the other end of which is connected to the calf frame, so as to drive the calf frame to rise and fall synchronously when the backrest rises and falls.

2. The three-folding rod rotating shaft sliding groove movable calf backrest frame linkage mechanism according to claim 1 is characterized in that: The base is provided with a sliding arm, and a sliding groove is provided in the sliding arm for the linkage component to slide therein, and the sliding groove is inclined. When the linkage component slides in the sliding groove, the lifting and lowering of the backrest is synchronized with the lifting and lowering of the calf frame.

3. The three-folding rod rotating shaft sliding groove movable calf backrest frame linkage mechanism according to claim 2 is characterized in that: The linkage assembly includes a rotating rod and a first support rod and a second support rod respectively hinged on both sides of the rotating rod, the other end of the first support rod is hinged on the base, the other end of the second support rod is hinged on the calf frame, a fixing part hinged on the backrest is arranged at the center of the rotating rod toward the backrest, and a pulley sliding in a slide groove is arranged toward the base.

4. The three-folding rod rotating shaft sliding groove movable calf backrest frame linkage mechanism according to claim 3 is characterized in that: A support arm is arranged on the base, and the support arm, the sliding arm and the base are connected to form a triangle, and the other end of the first support rod is hinged on the support arm.

5. The three-folding rod rotating shaft sliding groove movable calf backrest frame linkage mechanism according to claim 3 is characterized in that: The hinged part between the second support rod and the calf frame is located relatively below the hinged part between the backrest and the calf frame.

6. The three-folding rod rotating shaft sliding groove movable calf backrest frame linkage mechanism according to claim 3 is characterized in that: The fixing piece is arranged to pass through both sides of the rotating rod, and the side facing the back is a hinged part with a smooth surface, and the side facing the base is a fixing part with a threaded surface. The pulley is fixed on the fixing part, and a fixing nut is arranged outside the fixing part to form a fixed connection between the fixing piece and the rotating rod.

7. The three-folding rod rotating shaft sliding groove movable calf backrest frame linkage mechanism according to claim 1, characterized in that: A bearing plate is arranged on the backrest, and the bearing plate is fixed to the opposite front side of the hinge between the telescopic cylinder and the backrest.

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