A variable-force coiled leaf spring for a tower climbing unpowered exoskeleton joint

Abstract

A variable-force coiled leaf spring for a tower climbing unpowered exoskeleton joint belongs to the technical field of mechanical equipment, and includes an outer rotating disc, a rotating shaft, fixed spring plates and movable spring plates. In the present invention, friction is provided by the interlayer between the fixed spring plates and the movable spring plates to generate damping. The multi-layer movable spring plates with different lengths generate bending elastic deformation. As the number of rotations of the axis increases, the deformation amount of each spring plate also gradually increases. Therefore, by controlling the pre-adjusted number of rotations of the axis, different assisting torques are generated, and the adjustable range of assistance is wide, achieving the purpose of realizing customized stepless speed change for the supporting force of the exoskeleton joint. Applying the variable-force coiled leaf spring structure disclosed in the present invention can effectively reduce the eccentric force of the exoskeleton joint and improve the service life of the joint.

Description

Technical Field

[0001] The present invention belongs to the technical field of mechanical equipment, and particularly relates to a variable-force coiled leaf spring for a tower climbing unpowered exoskeleton joint. Background Art

[0002] Most of the energy storage mechanisms used in existing unpowered exoskeletons have a linear force curve, which has the disadvantages of few force levels and inability to set steplessly. Moreover, most of the energy storage mechanisms currently used in unpowered exoskeletons are linear springs, gas springs, elastic bands, etc. The above energy storage mechanisms can only provide force assistance for actions within a fixed variable force parameter range, with relatively large limitations. The clockwork springs used in the joints of existing unpowered exoskeletons have a constant force as the assistance. When used in the joints of tower climbing unpowered exoskeletons, the variation range is small, and it takes a long time to adjust to the appropriate force, which cannot well meet the application of exoskeleton joints.

[0003] Therefore, there is an urgent need for a new technical solution in the prior art to solve this problem. Summary of the Invention

[0004] The technical problem to be solved by the present invention is: to provide a variable-force coiled leaf spring for a tower climbing unpowered exoskeleton joint, because the assistance provided by the clockwork spring used in the joint of the existing unpowered exoskeleton is a constant force, the variation range is small, and it takes a long time to adjust to the appropriate force, which cannot well meet the application of exoskeleton joints.

[0005] A variable-force coiled leaf spring for a tower climbing unpowered exoskeleton joint includes an outer rotating disk, a rotating shaft, and also includes fixed spring leaves and movable spring leaves. There are two or more groups of fixed spring leaves and their lengths are all the same. The inner fixed ends of the two or more groups of fixed spring leaves are fixedly connected to the rotating shaft and the connection points are evenly arranged on the outer circumference of the rotating shaft. The outer fixed ends of the two or more groups of fixed spring leaves are fixedly connected to the outer rotating disk and the connection points are evenly arranged on the inner circumference of the outer rotating disk;

[0006] The outer fixed end of the movable spring leaf is fixedly connected to the inner circumference of the outer rotating disk and the connection points are evenly arranged. At the same time, the connection points of the outer fixed end of the movable spring leaf and the connection points of the outer fixed end of the fixed spring leaf are arranged at intervals. A cross hook is provided at the end of the inner movable end of the movable spring leaf. The inner movable end of the movable spring leaf is vacant between two adjacent fixed spring leaves. The lengths of the movable spring leaves are not the same and are all smaller than the lengths of the fixed spring leaves.

[0007] The fixed spring leaves are arranged in pairs, the rotation directions of the fixed spring leaves are the same, and the connection points of the inner fixed ends of the two paired fixed spring leaves are symmetrically arranged, and the connection points of the outer fixed ends of the two paired fixed spring leaves are symmetrically arranged.

[0008] The movable spring plates are arranged in pairs, and the number of movable spring plates does not exceed that of the fixed spring plates. The outer fixed end connection points of the movable spring plates are symmetrically arranged.

[0009] Through the above design, the present invention can bring the following beneficial effects:

[0010] The present invention provides a variable-force coiled leaf spring applied to a non-powered exoskeleton joint for climbing a high-voltage tower. Friction is generated between the interlayer between the fixed spring plates and the movable spring plates to provide damping. The multi-layer movable spring plates with different lengths generate bending elastic deformation. As the number of rotation circles of the axis increases, the deformation amount of each spring plate gradually increases. Therefore, by controlling the pre-adjusted number of rotation circles of the axis, different assisting torques are generated, and the adjustable range of assistance is wide, achieving the purpose of customizing the stepless speed change of the supporting force of the exoskeleton joint. Applying the variable-force coiled leaf spring structure disclosed by the present invention can effectively reduce the eccentric force of the exoskeleton joint and improve the service life of the joint. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] The following further describes the present invention in conjunction with the drawings and specific embodiments:

[0012] Figure 1 It is a schematic structural diagram of a variable-force coiled leaf spring for a non-powered exoskeleton joint for climbing a tower in the present invention.

[0013] Figure 2 It is a schematic structural diagram of an exoskeleton joint to which a variable-force coiled leaf spring for a non-powered exoskeleton joint for climbing a tower in the present invention is applied.

[0014] Figure 3 It is a curve diagram of the deformation and elastic force of a variable-force coiled leaf spring for a non-powered exoskeleton joint for climbing a tower in the present invention.

[0015] Figure 4 It is a curve diagram of the deformation and elastic force of a single spring plate in the prior art.

[0016] In the figure, 1 - outer rotating disk, 2 - rotating shaft, 3 - fixed spring plate, 4 - movable spring plate, 5 - cross hook, 301 - spring plate Ⅰ, 302 - spring plate Ⅱ, 401 - spring plate Ⅲ, 402 - spring plate Ⅳ. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0017] Embodiment:

[0018] As shown in the figure, the specific structure of a variable-force coiled leaf spring for a non-powered exoskeleton joint for climbing a tower includes an outer rotating disk 1, a rotating shaft 2, a fixed spring plate 3 and a movable spring plate 4. The fixed spring plate 3 includes a spring plate Ⅰ 301 and a spring plate Ⅱ 302; the movable spring plate 4 includes a spring plate Ⅲ 401 and a spring plate Ⅳ 402.

[0019] The two ends of the spring plate Ⅰ 301 and the spring plate Ⅱ 302 are respectively connected to the outer rotating disc 1 and the rotating shaft 2, and the spring plate Ⅰ 301 and the spring plate Ⅱ 302 are arranged in pairs at symmetrical positions. One end of the spring plate Ⅲ 401 and the spring plate Ⅳ 402 is connected to the outer rotating disc 1, and a cross hook 5 is arranged at the other end and clamped between the spring plate Ⅰ 301 and the spring plate Ⅱ 302.

[0020] Usage process: When in use, the outer rotating disc 1 and the rotating shaft 2 need to be respectively connected to the rotating joints of the climbing exoskeleton.

[0021] Working principle: According to Hooke's law, F = kx, where F is the generated elastic force, k is the stiffness coefficient, and x is the deformation amount. The stress and strain in the material are linearly related to the unit deformation amount. Therefore, when arranging the spring plates, the stiffness coefficient is related to the material, cross-sectional shape, and cross-sectional size of the spring. When the deformation increases, the elastic force increases linearly.

[0022] The coiled leaf spring refers to several spring plates with helical lines stacked in a plane. Taking the combination of four spring plates as an example in the present invention, the spring plate Ⅰ 301 and the spring plate Ⅱ 302 have the same length. One end is fixed to the outer rotating disc 1, and the other end is connected to the rotating shaft 2. After being subjected to the torque of the rotating shaft 2, the spring plate Ⅰ 301 and the spring plate Ⅱ 302 are bent. The length of the spring plate Ⅲ 401 is shorter than that of the spring plate Ⅰ 301 and the spring plate Ⅱ 302, and the length of the spring plate Ⅳ 402 is shorter than that of the spring plate Ⅲ 401. As the number of turns of the rotating shaft 2 increases, the spring plate Ⅰ 301 and the spring plate Ⅱ 302 are deformed first. If the stiffness coefficient of the spring plate Ⅰ 301 and the spring plate Ⅱ 302 is k1, then the force F = 2k1x1 generated at this time. When the deformation amount of the spring plate Ⅰ 301 and the spring plate Ⅱ 302 gradually increases, the spring plate Ⅲ 401 and the spring plate Ⅳ 402 also begin to be deformed successively. The stiffness coefficients of the spring plate Ⅲ 401 and the spring plate Ⅳ 402 are k2 and k respectively. 3， Then F = 2k1(x1 + x2 + x3) + k2(x2 + x3) + k3x3. Therefore, by controlling the pre-adjusted deformation amount, a gradually increasing assisting torque can be generated, and the increasing degree exceeds the linear effect of a single strip.

[0023] After the spring plate is installed on the joint, since the rotating shaft 2 and the external rotation disc 1 form a whole, due to the force compression of the spring plate inside, relative acting forces and reaction forces are generated on the external rotation disc 1 and the rotating shaft 2. When there is a single spring plate, the force is decomposed in the X and Y axis directions, generating unidirectional acting forces on the external rotation disc 1 and the rotating shaft 2 respectively. Therefore, in addition to generating a certain torque, the external rotation disc 1 and the rotating shaft 2 also generate eccentric forces in the axial direction, causing bending moments on the external rotation disc 1 and the rotating shaft 2 and resulting in unbalanced forces. Therefore, this force is an adverse factor affecting mechanical stability in the rotating structure, leading to a reduction in the service life of the joint. In the embodiment of the present invention, there are four spring plates, which appear in pairs at symmetrical positions. Taking the force analysis of two spring plates as an example, in addition to generating a torque due to the distance between the force application point and the axis, the external rotation disc 1 and the rotating shaft 2 have corresponding force balance in the X and Y directions. Therefore, when the spring plates appear in pairs, the eccentric force can be effectively eliminated and reduced, leaving only the torque required for joint movement and improving the service life of the joint.

[0024] Finally, it should be noted that the above are only preferred embodiments of the present invention and are not used to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, for those skilled in the art, they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements for some of the technical features. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A variable force coil leaf spring for a tower climbing unpowered exoskeleton joint, comprising an outer rotating disk (1) and a rotating shaft (2), characterized in that: It further includes a fixed spring piece (3) and a movable spring piece (4). There are two or more groups of the fixed spring pieces (3) and their lengths are all the same. The inner fixed ends of the two or more groups of fixed spring pieces (3) are fixedly connected to the rotating shaft (2), and the connection points are evenly arranged on the outer circumference of the rotating shaft (2). The outer fixed ends of the two or more groups of fixed spring pieces (3) are fixedly connected to the outer rotating disk (1), and the connection points are evenly arranged on the inner circumference of the outer rotating disk (1); The outer fixed end of the movable spring piece (4) is fixedly connected to the inner circumference of the outer rotating disk (1) and the connection points are evenly arranged. At the same time, the connection points of the outer fixed end of the movable spring piece (4) and the connection points of the outer fixed end of the fixed spring piece (3) are arranged at intervals. A cross hook (5) is provided at the end of the inner movable end of the movable spring piece (4). The inner movable end of the movable spring piece (4) is vacant between two adjacent fixed spring pieces (3). The lengths of the movable spring pieces (4) are not the same and are all smaller than the length of the fixed spring piece (3); The fixed spring pieces (3) are arranged in pairs. The rotation directions of the fixed spring pieces (3) are the same. And the connection points of the inner fixed ends of the two paired fixed spring pieces (3) are symmetrically arranged. The connection points of the outer fixed ends of the two paired fixed spring pieces (3) are symmetrically arranged; The movable spring pieces (4) are arranged in pairs, and the number of the movable spring pieces (4) does not exceed the number of the fixed spring pieces (3). The connection points of the outer fixed ends of the movable spring pieces (4) are symmetrically arranged.

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