Bumpers and bumpers pieces thereof

Abstract

The utility model discloses a lever piece which comprises a lever piece base, and the lever piece base is provided with a first extension body, a second extension body, a balance weight adjusting and assembling structure and a base body. An assembly hole is formed in the first tail end of the base body, the first extension body and the second extension body protrude out of the opposite second tail end of the base body in the opposite directions, and the first extension body and the second extension body are further arranged around the hole center line of the assembly hole or the center line parallel to the hole center line and are separated from each other; a plurality of counterweight adjusting and assembling structures are separated from one another and are arranged around the center line or the hole center line; according to the lever piece, the balance weight is assembled on the different balance weight adjusting and assembling structures, so that the requirement for micro-level weight adjustment can be met, on one hand, the use convenience is improved, and on the other hand, training in a real sports competition state does not need to depend on assistance of other complex shapes and different materials of equipment. In addition, the utility model further discloses a bar bell comprising the bar bell pieces and the bar shaft.

Description

Technical Field

[0001] This utility model relates to a training device for core training exercises, and more particularly to a barbell and its plates that are mainly used for strength training in sports competitions and fitness training. Background Technology

[0002] Currently, existing weight plates are mainly circular in shape, with fixed size and weight manufactured according to international standards. When the weight needs to be changed, the only way to adjust the overall weight is by increasing or decreasing the number of plates hanging on the bar axle. This involves loading and unloading weight plates of various weights in kilograms, which is very time-consuming and laborious, increasing the complexity of use.

[0003] Furthermore, to provide unstable physical effects or specific impact stimuli, additional devices with motion capabilities are required. For example, adding an off-axis motor inside the barbell, standing on a ground with variable directional motion, hanging chains on the bar plates, binding elastic rubber materials to the bar plates, or injecting water into the bar plates. Therefore, they can be broadly classified into two types: unstable external environment and unstable holding device.

[0004] In particular, the unstable external environment presents a flaw that is completely different from the conditions of most real sports competitions.

[0005] The main problem with unstable weight-bearing devices is the excessive external mechanical energy control, which does not reflect the real-world conditions of athletic competition. For example, the vibration frequency generated by an off-axis motor, in terms of stimulus frequency, stimulus intensity, and controllability training potential, does not match the athlete's actual internal body movement deviations. Similarly, with weighted chains, the length of the chain and the trajectory of the movement may interfere, leading to uncontrollable and unpredictable movements, resulting in loss of control and injury. Even with water-filled devices, which are closest to the real thing, the low density of water causes excessive fluctuations, deviating too much from the required simulation of interference for athletes, also increasing the risk of loss of control and injury. Furthermore, the fragility of plastic materials makes them prone to damage. Therefore, when measured against the principles of simulation in sports training science, this type of design is unlikely to gain acceptance or be converted into effective training for specific technical abilities.

[0006] Therefore, there is an urgent need for a barbell and its plates to overcome one or more of the aforementioned defects. Utility Model Content

[0007] One objective of this invention is to provide barbell plates that improve ease of use and allow for training in real sports competitions without relying on other complex shapes or equipment made of different materials, thereby ensuring the authenticity and reliability of training results.

[0008] Another objective of this invention is to provide bar plates that, on the one hand, improve ease of use, and on the other hand, allow for training in real sports competition conditions without relying on other complex shapes and different materials, thereby ensuring the authenticity and reliability of training results.

[0009] To achieve the above objectives, the lever plate of this utility model includes a lever plate base, which has a first extension body, a second extension body, a counterweight adjustment assembly structure, and a base. The first end of the base has an assembly hole for connecting to an external lever shaft; the first and second extension bodies extend in opposite directions and protrude from opposite second ends of the base, and are arranged around the center line of the assembly hole or a center line parallel to the center line of the hole and spaced apart from each other; the counterweight adjustment assembly structure consists of multiple structures arranged around the center line of the assembly hole or the center line of the hole and spaced apart from each other.

[0010] Compared with existing technologies, the design of this barbell plate, which features a mounting hole at the first end of the base for external bar shaft assembly, and a first and second extension body extending in opposite directions from opposite second ends of the base, with the first and second extension bodies arranged around or parallel to the center line of the mounting hole and spaced apart from each other, makes the shape of the barbell plate base resemble that of a ship's anchor. This allows the barbell plate of this invention to provide a larger swing amplitude and moment of inertia. Regarding weight adjustment, micro-level weight adjustments can be achieved by assembling counterweights onto different counterweight adjustment assembly structures, enabling the barbell plate of this invention to provide more refined training applications. Since the weight adjustment of the barbell plate of this invention only requires assembling counterweights onto different counterweight adjustment assembly structures, it is convenient to use without being time-consuming or laborious, and does not rely on other complex shapes or equipment made of different materials. Training is conducted under real sports competition conditions, thus ensuring the authenticity of the training effect. Therefore, the barbell plate of this invention has the following comparative advantages with the existing technology described in the background art:

[0011] (1) Existing circular bar plates are fixed in shape, size and weight, so they can only be used by combining them with larger intervals. However, the bar plates of this utility model can immediately increase or decrease the weight load by adding counterweights with smaller intervals, without having to painstakingly disassemble bar plates of various weights and quantities, thus increasing the convenience of actual use in training.

[0012] (2) Unstable stimulation requires special training modes that rely on other complex shapes and materials of equipment, but can only provide relatively simple and low-variability effects. The barbell plate of this utility model is used in combination with the bar axis, which is in line with the original usage habits and safety awareness. There is no need to use various auxiliary equipment with different shapes and materials, avoiding various troubles such as difficulty in handling, equipment damage, safety concerns, and limited effects.

[0013] (3) In terms of training systems with unstable external environments, which are completely different from most real sports competitions, the neural control modes are different from those in terms of motor neural control theory. The barbell plates of this invention do not change the user's actual standing or various postures of ground gravity. They are only amplified by physical design and contained within the body. This may interfere with the flow of force in motion control, increase the intensity of self-awareness of movement errors, and enable the trainee to activate a more effective and stronger neurophysiological self-control neural action mode, thereby improving the body's stability and coordination under external load challenge conditions.

[0014] (4) Regarding the weight-bearing device (wearable hand-held weight): The main problem is that there is too much external mechanical kinetic energy control, and it is not a projection of the real situation of sports competition. Taking the off-axis motor as an example, the vibration oscillation frequency generated is not the same as the athlete's real internal body movement deviation in terms of stimulus source frequency, stimulus intensity, and controllability training potential. Taking the weighted iron chain as an example, the length of the iron chain and the trajectory of the movement may interfere, resulting in uncontrollable and unexpected movements, leading to loss of control and injury. Or, the closest to the real original state is the water-filled hairpiece. Because the density of water is low, the resulting fluctuations are too large and the interference simulation required by the athlete is too far removed. It is also easy to cause loss of control and injury. Moreover, due to the fragility of plastic materials, it is also easy to cause damage. Therefore, if this type of design is measured by the simulation principle of sports training science, it is difficult to gain recognition and be converted into the original special technical ability training effect. In the barbell plate of this utility model, because it adopts the approach of "not changing the original principles of biomechanics, but only amplifying the subtle internal deviations of individuals, so as to avoid the "over-design pitfall", it can achieve the original intention of providing effective unstable stimulation training, while also truly meeting the basic requirements of training safety protection. This is the key to the product design. As for other aspects such as ease of organization, durability of equipment, ease of use of device, and cost economy, they have become part of the added value of this design.

[0015] Preferably, the first epitaxial body and the second epitaxial body are symmetrical to each other.

[0016] Preferably, the substrate is symmetrically arranged with respect to the plane of symmetry of the first epitaxial body and the second epitaxial body, the center line of the assembly hole is located in the plane of symmetry, and the center line is located in the plane of symmetry.

[0017] Preferably, in the direction from the second end of the substrate toward the first end of the substrate, the first end of the substrate is arranged to protrude relative to the first and second epitaxial bodies, and the substrate has an arc-shaped narrowing necking structure at a position between its first and second ends.

[0018] Preferably, the center line is located between the center line of the mounting hole and the second end of the substrate.

[0019] Preferably, the outer contours of the first epitaxial body, the second epitaxial body, and the substrate are located on a first cylindrical surface with the center line of the assembly hole or the center line as the center line.

[0020] Preferably, the inner contours of both the first and second extension bodies are located on a second cylindrical surface centered on the center line of the assembly hole or the center line.

[0021] Preferably, the inner contours on both sides of the first and second epitaxial bodies transition into the matrix in an arc shape.

[0022] Preferably, all the counterweight adjustment assembly structures are arranged at equal intervals; some of the counterweight adjustment assembly structures are located on the second end of the base, others are located on the first extension body, and the remainder are located on the second extension body.

[0023] Preferably, the barbell plate of this utility model further includes a counterweight for assembly connection with the counterweight adjustment assembly structure, the counterweight being selectively assembly connection with any of the counterweight adjustment assembly structures.

[0024] Preferably, the counterweight adjustment assembly structure is a threaded hole, and the counterweight has a corresponding external thread structure that is threadedly connected to the threaded hole; or, the counterweight adjustment assembly structure is an external thread structure, and the counterweight has a corresponding threaded hole that is threadedly connected to the external thread structure.

[0025] Preferably, the external thread structure or threaded hole is located at the center of the counterweight.

[0026] Preferably, the counterweight is a cylinder or a regular prism.

[0027] To achieve the above objectives, the lever of this utility model includes a lever shaft and the aforementioned lever plate, wherein the lever shaft is fitted into the mounting hole. Attached Figure Description

[0028] Figure 1 This is a three-dimensional view of the barbell of this utility model.

[0029] Figure 2 This is a perspective view of the barbell plate in the barbell of this utility model. The counterweight in the figure is assembled and connected with the counterweight adjustment assembly structure on the far left.

[0030] Figure 3 Is Figure 2 The diagram shows the state of the general's counterweight when it is assembled and connected to the fourth counterweight adjustment assembly structure from the left.

[0031] Figure 4 Is Figure 2 The diagram shows the state of the counterweight component when it is assembled and connected to the rightmost counterweight adjustment assembly structure.

[0032] Figure 5 yes Figure 4 A three-dimensional exploded view.

[0033] Figure 6 yes Figure 5 A top-down view of the layout with the counterweights concealed.

[0034] Figure 7 Is Figure 6 Based on this, a plan view of the first and second cylindrical surfaces is also shown.

[0035] Figure 8 yes Figure 5 A three-dimensional view of the counterweight component.

[0036] Figure 9 This is a three-dimensional diagram of another form of counterweight. Detailed Implementation

[0037] To explain the technical content and structural features of this utility model in detail, the following description is provided in conjunction with the embodiments and accompanying drawings.

[0038] Please see Figure 1 The barbell 100 of this utility model is mainly used for strength training in sports competitions and fitness training. It includes a barbell plate 100 and a bar shaft 200. The bar shaft 200 is inserted into the mounting hole 141 (mentioned below) of the barbell plate 100 to achieve the purpose of assembling the bar shaft 200 and the barbell plate 100 together. It should be noted that, although Figure 1 The only indication shown is that there are two barbell plates 100 on the bar axle 200. Obviously, the number of barbell plates 100 can vary depending on actual needs, and is determined by the specifications of the barbell 100. Therefore, it is not considered a specific number. Figure 1 The above is the limit.

[0039] Combined Figure 6 and Figure 7 As an example, the lever arm 100 includes a lever arm base 10 and a counterweight 20. The lever arm base 10 has a first extension 11, a second extension 12, a counterweight adjustment assembly structure 13, and a base 14. The first end 14a of the base 14 has an assembly hole 141 for assembling with the lever shaft 200. Optionally, in... Figures 1 to 5 In the example shown, the assembly hole 141 is a round hole to facilitate the machining of the assembly hole 141 on the base 14. Obviously, depending on actual needs, the assembly hole 141 can also be a regular polygonal hole or an elliptical hole, etc., so it is not considered as a specific example. Figure 6 and Figure 7 The above is for reference only. It should be noted that, since the mounting hole 141 is connected to the lever shaft 200, the lateral outer contour of the lever shaft 200 at the position for assembly with the mounting hole 141 is circular, regular polygonal, or elliptical, etc.

[0040] And combined Figures 2 to 5 As an example, the first epitaxial body 11 and the second epitaxial body 12 extend in opposite directions and protrude from the opposite second ends 14b of the matrix 14, for example, in Figures 1 to 7 In the example shown, the first epitaxial body 11 extends arcuately from the left side and protrudes from the second end 14b of the base 14, while the second epitaxial body 12 extends arcuately from the right side and protrudes from the second end 14b of the base 14. Obviously, depending on actual needs, the first epitaxial body 11 can also extend linearly from the left side and protrude from the second end 14b of the base 14, and the second epitaxial body 12 can extend linearly from the right side and protrude from the second end 14b of the base 14. Therefore, it is not considered... Figures 1 to 7 The diagram shows only the extent shown; furthermore, the first extension body 11 and the second extension body 12 are also arranged around a center line C2 parallel to the center line C1 of the assembly hole 141 and spaced apart from each other, as shown in the diagram. Figure 7 As shown. The counterweight adjustment assembly structure 13 consists of eight units arranged around the center line C2, spaced apart from each other. Obviously, depending on actual needs, the number of counterweight adjustment assembly structures 13 can also be two, three, four, five, six, seven, nine, or more. Therefore, it is not limited to... Figures 5 to 7 The above is the limit.

[0041] The counterweight 20 is used for assembly connection with the counterweight adjustment assembly structure 13, and the counterweight 20 can be selectively assembled with any of the counterweight adjustment assembly structures 13; wherein, Figure 2 The assembly connection between counterweight 20 and the leftmost counterweight adjustment assembly structure 13 is shown. Figure 3 The image shows the assembly connection between counterweight 20 and the fourth counterweight adjustment assembly structure 13 from the left. Figure 4The counterweight 20 is shown to be assembled and connected to the rightmost counterweight adjustment assembly structure 13; therefore, by selectively assembling the counterweight 20 with different counterweight adjustment assembly structures 13, the counterweight 20 can be positioned at different locations on the bar base 10, naturally resulting in swings of varying amplitudes and impacts on body stability through the physical principle of inertial motion. It should be noted that, although... Figures 2 to 4 The illustration shows how to achieve minute weight adjustments using only one counterweight 20 connected to different counterweight adjustment assembly structures 13. Obviously, depending on actual needs, multiple counterweights 20 can also be used connected to corresponding counterweight adjustment assembly structures 13 to achieve the same weight adjustment purpose. More specifically, as follows:

[0042] like Figure 6 As shown, as an example, the first epitaxial body 11 and the second epitaxial body 12 are symmetrical to each other, and the substrate 14 is symmetrically arranged with respect to the plane of symmetry P1 of the first epitaxial body 11 and the second epitaxial body 12, so as to facilitate the manufacturing and processing of the lever plate 100; at this time, the center line C1 of the assembly hole 141 is located in the plane of symmetry P1, and the center line C2 is located in the plane of symmetry P1, as shown in the figure. Figure 6 and Figure 7 As shown; alternatively, at Figure 6 and Figure 7 In this example, the center line C2 is located between the center line C1 and the second end 14b of the base 14, so that the wobbling sensation of the barbell plate 100 when connected to the counterweight 20 and different counterweight adjustment assembly structures 13 is more pronounced. Specifically, in Figures 1 to 7 In this example, in the direction from the second end 14b of the base 14 toward the first end 14a of the base 14, the first end 14a of the base 14 protrudes relative to the first extension body 11 and the second extension body 12, and the base 14 has an arc-shaped narrowing necked structure 14c located between its first end 14a and second end 14b; therefore, this design facilitates the operator's gripping operation of the barbell plate 100 during the assembly and disassembly of the barbell plate 100, thereby improving the reliability of the operator's gripping of the barbell plate 100; furthermore, in Figure 6 and Figure 7In this example, the outer contour 111 of the first extension body 11, the outer contour 121 of the second extension body 12, and the outer contour 141 of the base body 14 are located on the first cylindrical surface P2 with the center line C2 as the center line. The outer contours 111 of the first extension body 11, 121 of the second extension body 12, and 141 of the base body 14 are designed with an eccentricity relative to the center line C1 of the mounting hole 141. This design allows the barbell plate 100 to more effectively provide a larger swing amplitude and moment of inertia. Furthermore, it ensures that the outer arc radius and radius of the barbell plate 100 are the same as existing international barbell plates, thus guaranteeing the compatibility of the barbell plate 100 with existing international barbell plates. In addition, in... Figure 6 and Figure 7 In this example, the inner contour 112 of the first extension body 11 and the inner contour 122 of the second extension body 12 are located on the second cylindrical surface P3 with the center line C2 as the center line. The inner contours 112 of the first extension body 11 and 122 of the second extension body 12 are designed with an eccentricity relative to the center line C1 of the mounting hole 141, thus enabling the lever plate 100 to more effectively provide a larger swing amplitude and moment of inertia. To avoid stress concentration and facilitate manufacturing, in... Figure 6 and Figure 7 In the example, the inner contour 112 of the first extension body 11 transitions to the base body 14 in an arc shape, and the inner contour 122 of the second extension body 12 transitions to the base body 14 in an arc shape. The arc transition structure is shown in reference numeral 15.

[0043] like Figures 6 to 7 As shown, as an example, all the counterweight adjustment assembly structures 13 are arranged at equal intervals to ensure that the swaying sensation of the barbell plate 100 is more obvious and orderly, allowing for quantitative calculation and standardized control; furthermore, some of the counterweight adjustment assembly structures 13 are located on the second end 14b of the base 14, others are located on the first extension body 11, and the remainder are located on the second extension body 12. Specifically, in conjunction with Figures 1 to 8 In this example, the counterweight adjustment assembly structure 13 is a threaded hole, and the counterweight 20 correspondingly has an external thread structure 21 that connects to the threaded hole, facilitating quick assembly and disassembly of the counterweight 20 for easy adjustment. Obviously, depending on actual needs, the counterweight adjustment assembly structure 13 can also be an external thread structure, with a corresponding threaded hole on the counterweight 20, achieving the same purpose of connecting the counterweight 20 to the lever base 10 via a threaded connection. Therefore, it is not considered... Figures 1 to 8 The above is for reference only. More specifically, at [date / time]... Figure 8 In this example, the external thread structure 21 is located at the center of the counterweight 20 to ensure that the center of gravity of the counterweight 20 is located on the center line of the counterweight 20; furthermore, in Figure 8In the example shown, counterweight 20 is a regular prism; obviously, depending on actual needs, counterweight 20' can also be... Figure 9 The cylinder shown.

[0044] Compared with the prior art, the design of "the first end 14a of the base 14 has an assembly hole 141 for the assembly connection of the bar shaft 200, the first extension body 11 and the second extension body 12 extend in opposite directions and protrude from the opposite second end 14b of the base 14, and the first extension body 11 and the second extension body 12 are also arranged around the center line C1 of the assembly hole 141 or the center line C2 parallel to the center line C1 and spaced apart from each other" makes the shape of the bar plate base 10 similar to that of a ship anchor, thus enabling the bar plate 100 to provide a larger swing amplitude and rotational inertia; in terms of weight adjustment, micro-weight adjustment can be achieved by assembling the counterweight 20 on different counterweight adjustment assembly structures 13, thereby enabling the bar plate 100 to provide more detailed training applications. Since adjusting the weight of the barbell plate 100 only requires assembling the counterweight 200 onto different counterweight adjustment assembly structures 13, it is convenient to use without being time-consuming or laborious. Furthermore, it does not rely on other complex shapes or equipment made of different materials, allowing for training under real sports competition conditions and ensuring the authenticity of the training effect. Therefore, the comparison between this barbell plate 100 and the prior art described in the background art is as follows:

[0045] (1) Existing circular bar plates are fixed in shape, size and weight, so they can only be used in combination with larger intervals to fit into the bar axle. However, the bar plates 100 of this utility model can immediately increase or decrease the weight load by adding counterweights 20 with smaller intervals, without having to painstakingly disassemble bar plates of various weights and quantities, thus increasing the convenience of actual use on the training site.

[0046] (2) Unstable stimulation requires special training modes that rely on other complex shapes and materials of equipment, but can only provide relatively simple and low-variability effects. The barbell plate 100 of this utility model is used in combination with the bar shaft 200, which is in line with the original usage habits and safety awareness. There is no need to use various auxiliary equipment with different shapes and materials, avoiding various troubles such as difficulty in handling, equipment damage, safety concerns, and limited effects.

[0047] (3) In terms of training systems with unstable external environments, which are completely different from most real sports competitions, the viewpoints on motor neuron control theory are different neural control modes. The barbell plate 100 of this utility model does not change the user's actual standing or various postures of ground gravity. It only amplifies the force flow state of the body through physical design, which may interfere with the force flow state of motion control, increase the intensity of self-awareness of movement errors, and enable the trainee to activate a more effective and stronger neurophysiological self-control neural action mode, thereby improving the body stability and coordination under the challenge of external force load.

[0048] (4) Regarding the weight-bearing device (wearable hand-held weight): The main problem is that there is too much external mechanical kinetic energy control, and it is not a projection of the real situation of sports competition. Taking the off-axis motor as an example, the vibration oscillation frequency generated is not the same as the athlete's real internal body movement deviation in terms of stimulus source frequency, stimulus intensity, and controllability training potential. Taking the weighted iron chain as an example, the length of the iron chain and the trajectory of the movement may interfere, resulting in uncontrollable and unexpected movements, leading to loss of control and injury. Or, the closest to the real original state is the water-filled hairpiece. Because the density of water is low, the resulting fluctuations are too large and the interference simulation required by the athlete is too far removed. It is also easy to cause loss of control and injury. Moreover, due to the fragility of plastic materials, it is also easy to cause damage. Therefore, if this type of design is measured by the simulation principle of sports training science, it is difficult to gain recognition and be converted into the original special technical ability training effect. In the barbell plate 100 of this utility model, the key to the product design is that it achieves the goal of providing effective unstable stimulation training by "not changing the original principles of biomechanics, but only amplifying the subtle internal deviations of individuals, without falling into the "over-design trap". At the same time, it can also truly meet the basic requirements of training safety protection. As for other aspects such as ease of organization, durability of equipment, ease of use of device, and cost economy, they have become part of the added value of this design.

[0049] It is worth noting that although the attached drawings show the first elongated body 11 and the second elongated body 12 arranged around a center line C2 parallel to the center line C1 and spaced apart from each other, and all the counterweight adjustment assembly structures 13 arranged around the center line C2, it is clear that, depending on actual needs, the first elongated body 11 and the second elongated body 12 can also be arranged around the center line C1 and all the counterweight adjustment assembly structures 13 can be arranged around the center line C1 together, so it is not limited to what is shown in the attached drawings. Alternatively, the lever base 10 and the counterweight 20 (20') can be produced using lathe technology or casting technology, and then coated with rubber.

[0050] The above-disclosed examples are merely preferred embodiments of the present utility model and should not be construed as limiting the scope of the present utility model. Therefore, any equivalent variations made in accordance with the claims of the present utility model shall still fall within the scope of the present utility model.

Claims

1. A blade for a wind turbine, comprising a blade substrate, characterized in that, The lever base has a first extension body, a second extension body, a counterweight adjustment assembly structure, and a base. The first end of the base has an assembly hole for external lever shaft assembly connection. The first extension body and the second extension body extend in opposite directions and protrude from the opposite second ends of the base. The first extension body and the second extension body are also arranged around the center line of the assembly hole or a center line parallel to the center line of the hole and are spaced apart from each other. The counterweight adjustment assembly structure consists of multiple structures that are spaced apart from each other and arranged together around the center line or the center line of the hole.

2. The tablet according to claim 1, wherein The first epitaxial body and the second epitaxial body are symmetrical to each other. The matrix is ​​arranged symmetrically with the plane of symmetry of the first epitaxial body and the second epitaxial body as the center. The center line of the assembly hole is located in the plane of symmetry, and the center line is located in the plane of symmetry.

3. The tablet according to claim 1, wherein In the direction from the second end of the substrate toward the first end of the substrate, the first end of the substrate is arranged to protrude relative to the first epitaxial body and the second epitaxial body, and the substrate has an arc-shaped narrowing necking structure at the position between its first end and the second end.

4. The tablet according to claim 1, wherein The centerline is located between the centerline of the assembly hole and the second end of the substrate; the outer contours of the first elongation, the second elongation, and the substrate are located on a first cylindrical surface with the centerline of the assembly hole or the centerline as the center line; the inner contours of the first elongation and the second elongation are located on a second cylindrical surface with the centerline of the assembly hole or the centerline as the center line; the inner contours on both sides of the first elongation and the second elongation each transition to the substrate in an arc shape.

5. The tablet according to claim 1, wherein All the said counterweight adjustment assembly structures are arranged at equal intervals; some of the said counterweight adjustment assembly structures are located on the second end of the base, others of the said counterweight adjustment assembly structures are located on the first extension body, and the remainder of the said counterweight adjustment assembly structures are located on the second extension body.

6. The tablet according to claim 1, wherein It also includes a counterweight for assembly connection with the counterweight adjustment assembly structure, the counterweight being selectively assembly connection with any of the counterweight adjustment assembly structures.

7. The tablet according to claim 6, wherein The counterweight adjustment assembly structure is a threaded hole, and the counterweight has a corresponding external thread structure that is threadedly connected to the threaded hole; or, the counterweight adjustment assembly structure is an external thread structure, and the counterweight has a corresponding threaded hole that is threadedly connected to the external thread structure.

8. The tablet according to claim 7, wherein The external thread structure or threaded hole is located at the center of the counterweight.

9. The tablet according to claim 6, wherein The counterweight is a cylinder or a regular prism.

10. A lever comprising a lever shaft, characterized in that The lever also includes a lever plate according to any one of claims 1 to 9, wherein the lever shaft is fitted into the mounting hole.

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