A method for adjusting the axial stiffness of a connecting arm

Abstract

The application discloses a connecting arm axial rigidity adjusting method, which adjusts the axial rigidity of the connecting arm by changing the connecting length of a plate spring transversely connected between two connecting end faces of the connecting arm, characterized in that a plurality of limiting structures are arranged on one connecting face along the length adjusting path direction of the plate spring, and the limiting structures are used for realizing the step-by-step adjusting of the axial rigidity of the connecting arm. The application can realize the step-by-step adjusting of the axial rigidity of the connecting arm, and has the advantages of more stable and reliable rigidity adjusting, more convenient for beginners to master and use, and the like.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of linear rigidity adjustment of connecting arms, and particularly relates to a connecting arm axial rigidity adjustment method. BACKGROUND

[0002] In the rehabilitation process of fracture patients, especially patients with limb fracture, orthopedic external fixation supports are usually used to fix the fracture to avoid secondary injury during the rehabilitation process and accelerate the growth and rehabilitation of the fracture. The existing orthopedic external fixation support is usually composed of two fixing rings and a connecting arm connected between the fixing rings. When in use, the bone pins are installed on the fixing rings and fixed at both ends of the limb fracture, and then the relative positions of the fixing rings are adjusted by the connecting arm with telescopic function to keep the limb in a normal growth state.

[0003] In the conventional orthopedic external fixation support, the connecting arm can adjust the length, but the rigidity of the connecting arm itself cannot be adjusted. During the healing process of the limb fracture, the growth of the bone at different stages is different, which makes the rigidity and flexibility of the fixation support different, so the conventional orthopedic external fixation support cannot meet the needs. In order to improve the above-mentioned defects, the applicant considers installing a variable rigidity adjustment joint on the connecting arm of the orthopedic external fixation support to adjust the axial rigidity of the connecting arm according to the needs, so as to meet the needs of the change of the support rigidity at different stages during the healing process of the bone.

[0004] The applicant has designed a variable rigidity adjustment joint, the structure and adjustment principle of which are that a plurality of leaf springs are connected between the fixed disc and the adjustment disc, one end of the leaf spring is fixed at the shaft center of the fixed disc, and the other end is connected to an adjustment member, the adjustment member is slidably fitted in the sliding groove arranged in the screw direction on the adjustment disc. In this way, when the adjustment disc is rotated, the adjustment member slides in the sliding groove, thereby changing the connection length of the leaf spring and achieving the axial rigidity adjustment of the connecting arm. However, this adjustment method has the following defects: 1. The rehabilitation process of the patient with fracture usually includes several stages such as early stage, middle stage and late stage. The existing adjustment method is continuous and stepless, so there is no standard for adjusting to what degree in each rehabilitation stage, and it is entirely up to the doctor to judge according to experience, which is not conducive to beginners to master and use. 2. This structure relies on the leaf spring to connect between the fixed disc and the adjustment disc, and changes the rigidity by changing the spring force when the leaf spring is axially stressed. However, the leaf spring will bend when it is axially stressed, and the spring force generated by the bending will act on the adjustment member in the opposite direction, which can easily cause the position of the adjustment member in the sliding groove to change, resulting in changes in the axial rigidity, especially when the connecting arm is axially stressed or suddenly stressed, which can easily cause this situation and result in the failure of rigidity adjustment. Therefore, the stability is poor.

[0005] Therefore, how to design a variable stiffness adjustment mode capable of realizing grading and classification to facilitate beginners to master, and improving the adjustment stability and reliability becomes a problem to be solved by those skilled in the art. SUMMARY

[0006] In view of the above problems of the prior art, the technical problem to be solved by the present application is how to provide a connecting arm axial stiffness adjustment method which is more stable and reliable in adjustment and convenient for beginners to master.

[0007] In order to solve the above technical problem, the present application adopts the following technical scheme:

[0008] The present application discloses a connecting arm axial stiffness adjustment method, which adjusts the axial stiffness of the connecting arm by changing the connection length of the plate spring transversely connected between the two connecting end faces of the connecting arm, characterized in that a plurality of limiting structures are arranged on one connecting face along the length adjustment path direction of the plate spring, and the limiting structures are used to realize the grading and classification adjustment of the axial stiffness of the connecting arm.

[0009] In this way, in the present application, a plurality of limiting structures are arranged on the length adjustment path direction of the plate spring, and the grading and classification adjustment is realized, so that different stages of rehabilitation can be set correspondingly in different gears during adjustment, thereby greatly reducing the use difficulty of the operator. Meanwhile, each gear has a limiting structure during adjustment, and the limiting structure is used to bear the component force generated in the length adjustment direction of the plate spring due to the deformation of the plate spring during the axial force bearing process of the connecting arm, so as to avoid the influence of the component force on the displacement of the adjustment member and cause instability, thereby greatly improving the reliability and stability of the adjustment.

[0010] Further, the present application is realized by the following connecting arm variable stiffness adjustment device, which comprises a fixed disc and an adjustment disc, the fixed disc and the adjustment disc each have a connecting end opposite to each other and a mounting end in opposite directions, the mounting end of the fixed disc is used to be coaxially fixedly mounted on the butt joint end of one section of the connecting arm, and the mounting end of the adjustment disc is used to be coaxially and rotatably mounted on the butt joint end of another section of the connecting arm; further comprising a plurality of plate springs which are arranged along the circumference and uniformly distributed between the connecting ends of the fixed disc and the adjustment disc, the plate springs are arranged along the radial direction of the cross section, the inner end of the plate spring is rotatably mounted at the shaft center of the connecting end end face of the fixed disc, and the outer end of the plate spring is fixedly arranged on the adjustment disc, a adjusting frame which is a force bearing fulcrum of the plate spring is slidably sleeved on the plate spring, an associated structure is arranged between the adjusting frame and the adjustment disc, so that the adjusting frame can slide along the plate spring with the rotation of the adjustment disc, and a plurality of limiting protrusions are arranged on the connecting end end face of the fixed disc or the adjustment disc corresponding to each plate spring, the limiting protrusions are arranged on the adjusting path of the adjusting frame along the diameter direction perpendicular to the device cross section circle in sequence and are limited.

[0011] Thus, when the device is used, only need to rotate the adjusting disc, so that the adjusting frame is slid along the leaf spring and is limited by the limiting protrusions at different gear positions, since the adjusting frame is the force bearing point of the leaf spring, thus the effective action distance of the leaf spring is changed, and the adjustment of the axial connection stiffness is realized. The adjustment is convenient and fast, and each adjusting gear position is provided, so that the step-by-step and gear-by-gear adjustment is realized, the stiffness adjustment operation in different rehabilitation stages is facilitated, and the operation difficulty of the operator is reduced. After the adjustment to each gear position, the limiting protrusions limit the adjusting frame, so that the stability of the position is ensured, the adjusting frame will not be displaced due to the deformation of the leaf spring caused by the axial force of the connecting arm, and the stability and reliability of the work are ensured. Thus, the above-mentioned connecting arm variable stiffness adjusting device also has the characteristics of simple structure, convenient adjustment, and reliable and stable gear positioning. Of course, other structure modes capable of realizing the gear limiting can also be adopted to realize the step-by-step and gear-by-gear adjustment.

[0012] Further, the direction of the fixing disc face to the adjusting disc has a coaxial protrusion, and the outer end of the protrusion is the connecting end of the fixing disc; the adjusting disc includes an adjusting disc body and an overall cylindrical shell fixedly arranged outside the adjusting disc body, the end of the shell away from the fixing disc forms the mounting end of the adjusting disc, the end of the shell face to the fixing disc extends to the fixing disc and is inwardly folded to extend to the outer side surface of the protrusion of the fixing disc, so that an installation cavity is surrounded among the shell, the outer side surface of the protrusion and the adjusting disc body, and the leaf spring and the adjusting frame are located in the installation cavity.

[0013] Thus, the installation and fixation of the adjusting disc can be facilitated, and the structures such as the leaf spring and the adjusting frame can be protected.

[0014] Further, the outer end of the leaf spring is fixed on the inner side surface of the shell, and a tension spring arranged in the same direction as the leaf spring is also fixedly arranged on the inner side surface of the shell, and the other end of the tension spring is fixed on the adjusting frame to form the associated structure, and the limiting protrusions are arranged on the side of the adjusting frame where the tension spring is located.

[0015] Thus, due to the tension of the tension spring, the adjusting frame can slide along the leaf spring and be limited by the limiting protrusions during the rotation of the adjusting disc, and the structure is simple and the action is stable and reliable.

[0016] Further, in each group of limiting protrusions, the sides of the limiting protrusions face to the adjusting frame are sequentially connected through smooth transition inclined surfaces. Thus, the reverse rotation of the adjusting disc can be facilitated to realize the reset of the adjusting frame through the sliding of the inclined surfaces.

[0017] Further, the tension spring is a spiral spring, and a telescopic rod is further arranged inside the tension spring, and the two ends of the telescopic rod are respectively fixed on the inner side surface of the shell and the outer side surface of the adjusting frame.

[0018] Thus, the stability of the tension spring can be facilitated.

[0019] Further, the two ends of the adjusting frame are slidably fitted between the connecting end face of the adjusting disc and the inner end face of the shell, the adjusting frame is in a U shape and the open side of the U shape faces the adjusting plate, the inner end face of the U shape opening of the adjusting frame and the leaf spring are slidably attached, and the protruding side surface of the limiting protrusion is located at the height position of the opposite side of the leaf spring.

[0020] In this way, when the connecting arm is subjected to tension, the inner end face of the U shape opening of the adjusting frame and the leaf spring form a force point of the leaf spring, and the effective length of the leaf spring is the length between the adjusting frame and the boss of the fixing disc. When the connecting arm is subjected to compression, the protruding side surface of the limiting protrusion and the leaf spring form a force point of the leaf spring, and the effective length of the leaf spring is the length between the limiting protrusion of the current gear and the boss of the fixing disc. In this way, the adjusting frame is in a U shape, which is more convenient for sliding on the leaf spring during adjustment, and the overall structure is more stable and reliable.

[0021] In summary, the scheme of the present application can realize step-by-step adjustment of the axial rigidity of the connecting arm, has the advantages of more stable and reliable rigidity adjustment, more convenient for beginners to master and use, etc. BRIEF DESCRIPTION OF DRAWINGS

[0022] Figure 1 It is a structural schematic diagram of the present application.

[0023] Figure 2 It is a structural schematic diagram of the present application. Figure 1 It is a structural schematic diagram of the present application.

[0024] Figure 3 It is a sectional view of the present application. Figure 1 EMBODIMENT

[0025] The present application will be further described in detail below in combination with specific embodiments.

[0026] In specific implementation: a connecting arm axial rigidity adjustment method, which realizes adjustment of the axial rigidity of the connecting arm by changing the connection length of the leaf spring transversely connected between the two connecting end faces of the connecting arm, characterized in that a plurality of limiting structures are arranged on one connecting face along the length adjustment path direction of the leaf spring, and the limiting structures are used to realize step-by-step adjustment of the axial rigidity of the connecting arm.

[0027] In this way, in the present scheme, a plurality of limiting structures are arranged in the adjustment path direction of the leaf spring, step-by-step adjustment is realized, different gears during adjustment can be correspondingly set for different rehabilitation stages, which greatly reduces the difficulty of use of the operator. At the same time, each gear during adjustment has a limiting structure, the limiting structure is used to bear the component force in the adjustment direction of the leaf spring caused by the deformation of the leaf spring during the axial force bearing process of the connecting arm, avoids the influence of the component force on the displacement of the adjusting member and causes instability, and greatly improves the reliability and stability of the adjustment. ​

[0028] In this embodiment, the method relies on the following connecting arm variable stiffness adjustment device, which is described in [reference needed]. Figures 1-3 As shown, it includes a fixed plate 1 and an adjusting plate 3. The fixed plate 1 and the adjusting plate 3 each have a connecting end facing each other and an mounting end in opposite directions. The mounting end of the fixed plate 1 is used to be coaxially fixedly mounted on the docking end of one section of the connecting arm. The mounting end of the adjusting plate 3 is used to be coaxially and rotatably mounted on the docking end of the other section of the connecting arm. It also includes a plurality of leaf springs 5 ​​evenly distributed in a ring between the connecting ends of the fixed plate and the adjusting plate. The leaf springs 5 ​​are arranged radially along the cross section. The inner end of the leaf spring is rotatably mounted at the axis of the end face of the connecting end of the fixed plate. The outer end of the leaf spring is relatively fixed on the adjusting plate. An adjusting frame 7 is slidably sleeved on the leaf spring 5 as the supporting point of the leaf spring. An association structure is provided between the adjusting frame 7 and the adjusting plate 3 so that the adjusting frame can slide along the leaf spring with the rotation of the adjusting plate. A set of several limiting protrusions 8 are provided on the end face of the connecting end of the fixed plate or the adjusting plate, corresponding to each leaf spring. The limiting protrusions 8 are arranged in sequence along the diameter direction (of the cross section circle) on the adjusting path of the adjusting frame and limit it.

[0029] In this way, when using this device, simply rotating the adjustment disc allows the adjustment frame to slide along the leaf spring and be adjusted to the limit protrusions at different positions. Since the adjustment frame is the load-bearing fulcrum of the leaf spring, it is equivalent to changing the effective working distance of the leaf spring, thus achieving adjustment of the axial connection stiffness. Adjustment is convenient and quick, and various adjustment positions are provided, enabling graded and graded adjustment, facilitating stiffness adjustment operations at different rehabilitation stages and reducing the operator's difficulty. Furthermore, after adjustment to each position, the limit protrusions limit the adjustment frame, ensuring its positional stability and preventing displacement of the adjustment frame due to leaf spring deformation caused by axial force on the connecting arm, thus ensuring operational stability and reliability.

[0030] In practice, the inner end of each leaf spring 5 is fixed radially to a turntable 4, and the connecting ends of the turntable and the fixed plate are coaxial and rotatably connected. This facilitates the installation of each leaf spring.

[0031] The fixed disk 1 has a coaxial boss facing the adjusting disk 3, and the outer end of the boss is the connecting end of the fixed disk. The adjusting disk 3 includes an adjusting disk body and an integral cylindrical outer shell 2 fixedly disposed outside the adjusting disk body. The end of the outer shell 2 away from the fixed disk forms the mounting end of the adjusting disk. The end of the outer shell 2 facing the fixed disk extends towards the fixed disk and folds inward to the outer side of the boss of the fixed disk 1, so that a mounting cavity is formed between the outer shell, the outer side of the boss and the adjusting disk body. The leaf spring 5 and the adjusting bracket 7 are located in the mounting cavity.

[0032] Thus, the installation and fixation of the adjusting disc can be conveniently adjusted, and the leaf spring and the adjusting frame and other structures can be protected.

[0033] The outer end of the leaf spring is fixed on the inner side of the shell, and a tension spring arranged in the same direction as the leaf spring is also fixed on the inner side of the shell. The other end of the tension spring is fixed on the adjusting frame to form the associated structure. The limiting protrusions are arranged on the side of the adjusting frame where the tension spring is located.

[0034] Thus, the adjusting frame can slide along the leaf spring and be limited by the limiting protrusions during the rotation of the adjusting disc due to the tension of the tension spring. The structure is simple, and the action is stable and reliable.

[0035] In each group of limiting protrusions, the sides of the limiting protrusions facing the adjusting frame are sequentially connected by smooth transition inclined surfaces. Thus, the adjusting disc can be conveniently reversed to reset the adjusting frame through the sliding of the inclined surfaces.

[0036] The tension spring is a coil spring, and a telescopic rod 6 is further arranged in the tension spring. The two ends of the telescopic rod 6 are respectively fixed on the inner side of the shell and the outer side of the adjusting frame.

[0037] Thus, the stability of the tension spring can be conveniently maintained.

[0038] The two ends of the adjusting frame 7 are slidably matched between the end face of the connecting end of the adjusting disc 3 and the inner end face of the shell. The adjusting frame 7 is in a U shape, and the open side faces the adjusting plate. The inner end face of the U-shaped opening of the adjusting frame and the leaf spring 5 are slidably attached. The protruding side surface of the limiting protrusion 8 is located at the height position of the opposite side of the leaf spring.

[0039] Thus, when the connecting arm is subjected to tension, the inner end face of the U-shaped opening of the adjusting frame and the leaf spring form the force fulcrum of the leaf spring. The effective length of the leaf spring is the length between the adjusting frame and the boss of the fixed disc. When the connecting arm is subjected to compression, the protruding side surface of the limiting protrusion and the leaf spring form the force fulcrum of the leaf spring. The effective length of the leaf spring is the length between the limiting protrusion of the current gear and the boss of the fixed disc. Thus, the adjusting frame is in a U shape, which is more convenient for sliding on the leaf spring during adjustment, and the overall structure is more stable and reliable.

[0040] Therefore, the above-mentioned connecting arm variable stiffness adjusting device also has the characteristics of simple structure, convenient adjustment, and reliable and stable gear limiting. Of course, other variable stiffness adjusting device structures that can realize gear limiting can also be used to realize step-by-step and gear-by-gear adjustment during implementation, such as replacing the boss with a connecting end arranged on the fixed disc, or replacing the tension spring with a push spring fixed on the side of the fixed disc, and the like, which will not be described in detail here.

Claims

1. A variable stiffness adjustment device for a connecting arm, characterized in that The device comprises a fixed disc and an adjusting disc, each of which has a connecting end and an opposite mounting end, the mounting end of the fixed disc is coaxially fixedly mounted on the butt joint end of one section of the connecting arm, and the mounting end of the adjusting disc is coaxially and rotatably mounted on the butt joint end of another section of the connecting arm; the device further comprises a plurality of leaf springs which are uniformly distributed along the ring between the connecting ends of the fixed disc and the adjusting disc, the leaf springs are arranged along the radial direction of the cross section, the inner end of the leaf spring is rotatably mounted at the center of the end surface of the connecting end of the fixed disc, the outer end of the leaf spring is fixedly arranged on the adjusting disc, a regulating frame which is a force supporting point of the leaf spring is slidably sleeved on the leaf spring, a relevant structure is arranged between the regulating frame and the adjusting disc so that the regulating frame can slide along the leaf spring with the rotation of the adjusting disc, a plurality of limiting protrusions corresponding to each leaf spring are arranged on the end surface of the connecting end of the fixed disc or the adjusting disc, and the limiting protrusions are arranged on the adjusting path of the regulating frame in the direction perpendicular to the diameter direction and are limited thereon. The fixed disc has a coaxial boss in the direction facing the adjusting disc, and the outer end of the boss is the connecting end of the fixed disc; the adjusting disc comprises an adjusting disc body and an integral cylindrical shell fixedly arranged outside the adjusting disc body, the end of the shell away from the fixed disc forms the mounting end of the adjusting disc, the end of the shell facing the fixed disc extends towards the fixed disc and is inwardly folded to extend to the outer side surface of the boss of the fixed disc, so that an installation cavity is formed between the shell, the outer side surface of the boss and the adjusting disc body, and the leaf spring and the regulating frame are located in the installation cavity. The outer end of the leaf spring is fixed on the inner side surface of the shell, a tension spring arranged in the same direction as the leaf spring is also fixedly arranged on the inner side surface of the shell, the other end of the tension spring is fixed on the regulating frame to form the relevant structure, and the limiting protrusions are arranged on the side of the regulating frame where the tension spring is located.

2. The connecting arm variable stiffness adjustment device of claim 1, wherein, In each group of limiting protrusions, the sides of the limiting protrusions facing the regulating frame are sequentially connected by smooth transition inclined surfaces.

3. The connecting arm variable stiffness adjustment device of claim 1, wherein, The tension spring is a spiral spring, and a telescopic rod is further arranged inside the tension spring, and the two ends of the telescopic rod are respectively fixed on the inner side surface of the shell and the outer side surface of the regulating frame.

4. The connecting arm variable stiffness adjustment device of claim 1, wherein, The two ends of the regulating frame are slidably fitted between the end surface of the connecting end of the adjusting disc and the inner end surface of the shell, the regulating frame is in the shape of U and has an opening side facing the adjusting disc, the inner end surface of the U-shaped opening of the regulating frame is slidably attached to the leaf spring, and the protruding side surface of the limiting protrusion is located at the height position of the opposite side surface of the leaf spring.

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