Automatic conveying and weighing device
By using a multi-stage conveying structure and an automated control system, the problem of low efficiency in manual weighing during material conveying has been solved, achieving efficient and accurate automatic weighing and unattended operation, thus improving the intelligence level of the production line.
Patent Information
- Application Number
- CN202520049020.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-01-09
- Publication Date
- 2025-12-09
- Estimated Expiration
- 2035-01-09
AI Technical Summary
In existing technologies, weighing during material conveying is usually done manually, which leads to low efficiency.
It adopts a multi-stage conveying structure, equipped with a special rotating gear and chain, combined with a weight sensor and telescopic rod to achieve automated weighing, and integrates with the automatic control system through a motor to achieve unattended operation.
It improves material conveying efficiency and weighing accuracy, reduces manual intervention, lowers energy consumption, extends equipment lifespan, and enhances the intelligence level of the production line.
Smart Images
Figure CN223649977U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of automatic conveying and weighing technology, and in particular to an automatic conveying and weighing device. Background Technology
[0002] An automated conveyor weighing device is a piece of equipment that combines an automated conveying system with precise weighing technology. It can monitor and record the weight of items in real time while conveying materials. Automated conveyor weighing devices enable automatic material conveying and weighing, significantly improving the overall efficiency of the production line. Through high-precision sensors and an intelligent control system, they accurately record the weight of each piece of material, ensuring data consistency and reliability. Even during long periods of continuous operation, the automated equipment maintains a stable working state, reducing the occurrence of human error. Furthermore, the device monitors material weight in real time, ensuring that each production stage meets quality requirements.
[0003] Currently, weighing during material transportation is usually done manually, which is cumbersome and results in low efficiency for the entire transportation weighing process. Utility Model Content
[0004] The purpose of this invention is to provide an automatic conveying and weighing device to solve the above-mentioned problems.
[0005] This utility model achieves the above objectives through the following technical solutions:
[0006] An automatic conveying and weighing device includes:
[0007] A first main conveyor shaft (a1) and several first slave conveyor shafts (b1); one end of the first main conveyor shaft (a1) is fixedly connected to one end of the first right main rotating shaft (a2); the other end of the first right main rotating shaft (a2) passes through the first right support plate (a3) and is fixedly connected to the output end of the first motor (a4); the first right main rotating shaft (a2) is provided with a first right main rotating gear (a5); the bottom end of the first right support plate (a3) and the first right bottom plate (a6) are fixedly connected; the other end of the first main conveyor shaft (a1) is fixedly connected to one end of the first left main rotating shaft (a7); the other end of the first left main rotating shaft (a7) passes through the first left support plate (a8) and is rotatably connected to the first left support plate (a8); the first left main rotating shaft (a7) is provided with a first left main rotating gear (a9); the bottom end of the first left support plate (a8) and the first left bottom plate (a10) are fixedly connected; one end of the first slave conveyor shaft (b1) is fixedly connected to one end of the first right slave rotating shaft (b2). Connection; the other end of the first right driven rotating shaft (b2) passes through the first right support plate (a3) and is rotatably connected to the first right support plate (a3); the first right driven rotating shaft (b2) is provided with a first right driven rotating gear (b5); the bottom end of the first right support plate (a3) and the first right bottom plate (a6) are fixedly connected; the other end of the first driven conveying shaft (b1) is fixedly connected to one end of the first left driven rotating shaft (b7); the other end of the first left driven rotating shaft (b7) passes through the first left support plate. (a8) is rotatably connected to the first left support plate (a8); the first left driven rotating shaft (b7) is provided with a first left driven rotating gear (b9); the bottom end of the first left support plate (a8) is fixedly connected to the first left base plate (a10); the first right main rotating gear (a5) and several first right driven rotating gears (b5) are all meshed with the first right chain (a11); the first left main rotating gear (a5) and several first left driven rotating gears (b5) are all meshed with the first left chain (a12);
[0008] A second main conveyor shaft (c1) and several second slave conveyor shafts (d1); two ends of the second main conveyor shaft (c1) are fixedly connected to two ends of the second right main rotating shaft (c2); the other two ends of the second right main rotating shaft (c2) pass through the second right support plate (c3) and are fixedly connected to the output end of the second motor (c4); the second right main rotating shaft (c2) is provided with a second right main rotating gear (c5); the bottom end of the second right support plate (c3) and the second right bottom plate (c6) are fixedly connected; the other two ends of the second main conveyor shaft (c1) are fixedly connected to two ends of the second left main rotating shaft (c7); the other two ends of the second left main rotating shaft (c7) pass through the second left support plate (c8) and are rotatably connected to the second left support plate (c8); the second left main rotating shaft (c7) is provided with a second left main rotating gear (c9); the bottom end of the second left support plate (c8) and the second left bottom plate (c10) are fixedly connected; the two ends of the second slave conveyor shaft (d1) are fixedly connected to the two ends of the second right slave rotating shaft (d2). Connection; the other two ends of the second right driven rotating shaft (d2) pass through the second right support plate (c3) and are rotatably connected; the second right driven rotating shaft (d2) is provided with a second right driven rotating gear (d5); the bottom end of the second right support plate (c3) and the second right bottom plate (c6) are fixedly connected; the other two ends of the second driven conveying shaft (d1) are fixedly connected to the two ends of the second left driven rotating shaft (d7); the other two ends of the second left driven rotating shaft (d7) pass through the second left support plate. (c8) and the second left support plate (c8) are rotatably connected; the second left driven rotating shaft (d7) is provided with a second left driven rotating gear (d9); the bottom end of the second left support plate (c8) is fixedly connected to the second left base plate (c10); the second right main rotating gear (c5) and several second right driven rotating gears (d5) are all meshed with the second right chain (c11); the second left main rotating gear (c5) and several second left driven rotating gears (d5) are all meshed with the second left chain (c12);
[0009] A third main conveyor shaft (e1) and several third slave conveyor shafts (f1); the three ends of the third main conveyor shaft (e1) are fixedly connected to the three ends of the third right main rotating shaft (e2); the other three ends of the third right main rotating shaft (e2) pass through the third right support plate (e3) and are fixedly connected to the output end of the third motor (e4); the third right main rotating shaft (e2) is provided with a third right main rotating gear (e5); the bottom end of the third right support plate (e3) and the third right bottom plate (e6) are fixedly connected; the third The other three ends of the main conveying shaft (e1) are fixedly connected to the three ends of the third left main rotating shaft (e7); the other three ends of the third left main rotating shaft (e7) pass through the third left support plate (e8) and are rotatably connected to the third left support plate (e8); the third left main rotating shaft (e7) is provided with a third left main rotating gear (e9); the bottom end of the third left support plate (e8) is fixedly connected to the third left bottom plate (e10); the three ends of the third driven conveying shaft (f1) are fixedly connected to the three ends of the third right driven rotating shaft (f2). The third right-hand rotating shaft (f2) is rotatably connected to the third right support plate (e3) at its three ends; the third right-hand rotating shaft (f2) is provided with a third right-hand rotating gear (f5); the bottom end of the third right support plate (e3) is fixedly connected to the third right bottom plate (e6); the other three ends of the third-hand conveying shaft (f1) are fixedly connected to the three ends of the third left-hand rotating shaft (f7); the other three ends of the third left-hand rotating shaft (f7) pass through the third left support plate. (e8) and the third left support plate (e8) are rotatably connected; the third left driven rotating shaft (f7) is provided with a third left driven rotating gear (f9); the bottom end of the third left support plate (e8) and the third left bottom plate (e10) are fixedly connected; the third right main rotating gear (e5) and several third right driven rotating gears (f5) are all meshed with the third right chain (e11); the third left main rotating gear (e5) and several third left driven rotating gears (f5) are all meshed with the third left chain (e12);
[0010] A top plate (g1) is fixedly installed between the second right support plate (c3) and the second left support plate (c8), and a weight sensor (g2) is installed directly below the top plate (g1); the bottom end of the weight sensor (g2) is fixedly connected to the top ends of several telescopic rods (g3).
[0011] Compared with the prior art, the beneficial effects of this utility model are as follows:
[0012] 1. It adopts a multi-stage conveying structure (first, second, and third main conveying shafts and slave conveying shafts), each stage is equipped with a dedicated rotating gear and chain to achieve higher conveying efficiency; each level of conveying shaft and slave conveying shaft operates independently, which can flexibly handle different material loads and conveying needs, and is not prone to jamming or overload.
[0013] 2. The weight sensor (g2) is connected to the telescopic rod (g3) to accurately weigh the items. The telescopic rod can be automatically adjusted according to the size and weight of different items to ensure the accuracy of weighing.
[0014] 3. Motors (such as A4, C4, E4, etc.) can be integrated with automated control systems to achieve unattended operation, reduce manual intervention, and improve work efficiency. The entire device can be integrated with a central control system to achieve remote monitoring and adjustment, further enhancing the intelligence level of the production line.
[0015] 4. The meshing transmission design of gears and chains enables the device to provide stable driving force with low energy consumption, reducing the burden on the motor and improving overall efficiency; using multiple motors to share the load reduces the workload of each motor, lowers energy consumption, and extends the service life of the equipment. Attached Figure Description
[0016] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0017] Figure 1 A first perspective view of an automatic conveying and weighing device provided in an embodiment of the present invention is shown;
[0018] Figure 2 A second perspective view of an automatic conveying and weighing device provided in an embodiment of the present invention is shown;
[0019] Figure 3 This figure shows a front view of an automatic conveying and weighing device provided in an embodiment of the present invention;
[0020] Figure 4 The left view of an automatic conveying and weighing device provided in an embodiment of the present invention is shown;
[0021] Figure 5 The image shows a right view of an automatic conveying and weighing device provided in an embodiment of the present invention;
[0022] Figure 6 This figure shows a top view of an automatic conveying and weighing device provided in an embodiment of the present invention;
[0023] Figure 7 The image shows a bottom view of an automatic conveying and weighing device provided in an embodiment of the present invention. Detailed Implementation
[0024] In the description of this utility model, it should be understood that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model. In addition, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, features defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature. In the description of this utility model, unless otherwise stated, "a plurality of" means two or more.
[0025] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation", "connection" and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal connection of two components. For those skilled in the art, the specific meaning of the above terms in this utility model can be understood through the specific circumstances.
[0026] The present invention will be further described below with reference to the accompanying drawings:
[0027] like Figures 1-7 As shown, an automatic conveying and weighing device includes:
[0028] A first main conveyor shaft a1 and several first slave conveyor shafts b1; one end of the first main conveyor shaft a1 is fixedly connected to one end of the first right main rotating shaft a2; the other end of the first right main rotating shaft a2 passes through the first right support plate a3 and is fixedly connected to the output end of the first motor a4; the first right main rotating shaft a2 is provided with a first right main rotating gear a5; the bottom end of the first right support plate a3 is fixedly connected to the first right base plate a6; the other end of the first main conveyor shaft a1 is fixedly connected to one end of the first left main rotating shaft a7; the other end of the first left main rotating shaft a7 passes through the first left support plate a8 and is rotatably connected to the first left support plate a8; the first left main rotating shaft a7 is provided with a first left main rotating gear a9; the bottom end of the first left support plate a8 is fixedly connected to the first left base plate a10; one end of the first slave conveyor shaft b1 is fixedly connected to one end of the first right slave rotating shaft b2. Connect the first right driven rotating shaft b2; the other end of the first right driven rotating shaft b2 passes through the first right support plate a3 and is rotatably connected to the first right support plate a3; the first right driven rotating shaft b2 is provided with a first right driven rotating gear b5; the bottom end of the first right support plate a3 is fixedly connected to the first right base plate a6; the other end of the first driven conveying shaft b1 is fixedly connected to one end of the first left driven rotating shaft b7; the other end of the first left driven rotating shaft b7 passes through the first left support plate a8 and is rotatably connected to the first left support plate a8; the first left driven rotating shaft b7 is provided with a first left driven rotating gear b9; the bottom end of the first left support plate a8 is fixedly connected to the first left base plate a10; the first right main rotating gear a5 and several first right driven rotating gears b5 are all meshed with the first right chain a11; the first left main rotating gear a5 and several first left driven rotating gears b5 are all meshed with the first left chain a12;
[0029] A second main conveyor shaft c1 and several second slave conveyor shafts d1; two ends of the second main conveyor shaft c1 are fixedly connected to two ends of the second right main rotating shaft c2; the other two ends of the second right main rotating shaft c2 pass through the second right support plate c3 and are fixedly connected to the output end of the second motor c4; the second right main rotating shaft c2 is provided with a second right main rotating gear c5; the bottom end of the second right support plate c3 is fixedly connected to the second right base plate c6; the other two ends of the second main conveyor shaft c1 are fixedly connected to two ends of the second left main rotating shaft c7; the other two ends of the second left main rotating shaft c7 pass through the second left support plate c8 and are rotatably connected to the second left support plate c8; the second left main rotating shaft c7 is provided with a second left main rotating gear c9; the bottom end of the second left support plate c8 and the second left base plate c10 are fixedly connected. The two ends of the second slave conveyor shaft d1 are fixedly connected to the two ends of the second right slave rotating shaft d2. The second right driven rotating shaft d2 is rotatably connected to the second right support plate c3 at its two ends; the second right driven rotating shaft d2 is provided with a second right driven rotating gear d5; the bottom end of the second right support plate c3 is fixedly connected to the second right base plate c6; the other two ends of the second driven conveying shaft d1 are fixedly connected to the two ends of the second left driven rotating shaft d7; the other two ends of the second left driven rotating shaft d7 are rotatably connected to the second left support plate c8 at its two ends; the second left driven rotating shaft d7 is provided with a second left driven rotating gear d9; the bottom end of the second left support plate c8 is fixedly connected to the second left base plate c10; the second right main rotating gear c5 and several second right driven rotating gears d5 are all meshed with the second right chain c11; the second left main rotating gear c5 and several second left driven rotating gears d5 are all meshed with the second left chain c12;
[0030] A third main conveyor shaft e1 and several third slave conveyor shafts f1; three ends of the third main conveyor shaft e1 are fixedly connected to three ends of the third right main rotating shaft e2; the other three ends of the third right main rotating shaft e2 pass through the third right support plate e3 and are fixedly connected to the output end of the third motor e4; the third right main rotating shaft e2 is provided with a third right main rotating gear e5; the bottom end of the third right support plate e3 is fixedly connected to the third right base plate e6; the other three ends of the third main conveyor shaft e1 are fixedly connected to three ends of the third left main rotating shaft e7; the other three ends of the third left main rotating shaft e7 pass through the third left support plate e8 and are rotatably connected to the third left support plate e8; the third left main rotating shaft e7 is provided with a third left main rotating gear e9; the bottom end of the third left support plate e8 is fixedly connected to the third left base plate e10; the three ends of the third slave conveyor shaft f1 are fixedly connected to three ends of the third right slave rotating shaft f2. The third right driven rotating shaft f2 is connected to the third right support plate e3 by passing through its three ends; the third right driven rotating shaft f2 is equipped with a third right driven rotating gear f5; the bottom end of the third right support plate e3 is fixedly connected to the third right base plate e6; the third driven conveying shaft f1 is fixedly connected to the third left driven rotating shaft f7 by passing through its three ends; the third left driven rotating shaft f7 is connected to the third left support plate e8 by passing through its three ends; the third left driven rotating shaft f7 is equipped with a third left driven rotating gear f9; the bottom end of the third left support plate e8 is fixedly connected to the third left base plate e10; the third right main rotating gear e5 and several third right driven rotating gears f5 are all meshed with the third right chain e11; the third left main rotating gear e5 and several third left driven rotating gears f5 are all meshed with the third left chain e12;
[0031] A top plate g1 is fixedly installed between the second right support plate c3 and the second left support plate c8. A weight sensor g2 is installed directly below the top plate g1. The bottom of the weight sensor g2 is fixedly connected to the top of several telescopic rods g3.
[0032] By adopting a multi-stage conveying structure (first, second, and third main conveying shafts and slave conveying shafts), each stage is equipped with a dedicated rotating gear and chain to achieve higher conveying efficiency; each level of conveying shaft and slave conveying shaft operates independently, which can flexibly handle different material loads and conveying needs, while being less prone to jamming or overload.
[0033] The weight sensor (g2) is connected to the telescopic rod (g3) to accurately weigh the items. The telescopic rod can be automatically adjusted according to the size and weight of different items to ensure the accuracy of weighing.
[0034] Motors (such as A4, C4, E4, etc.) can be integrated with automated control systems to achieve unattended operation, reduce manual intervention, and improve work efficiency. The entire system can be integrated with a central control system for remote monitoring and adjustment, further enhancing the intelligence level of the production line.
[0035] The meshing transmission design of gears and chains enables the device to provide stable driving force with low energy consumption, reducing the burden on the motor and improving overall efficiency; using multiple motors to share the load reduces the workload of each motor, lowers energy consumption, and extends the service life of the equipment.
[0036] Working principle: In use, an empty material collection box is placed on the first conveyor shaft b1; the first motors a4 and c4 are started; the material collection box moves to the right; when the left end of the material collection box exceeds c1, motors a4 and c4 are turned off; the telescopic rod g3 is extended, causing the second right bottom plate c6 and the second left bottom plate c10 to leave the ground, thus weighing the material collected in the material collection box; when the weight of the material collected in the material collection box reaches a threshold, material feeding is stopped, and the telescopic rod g3 is shortened, causing the second right bottom plate c6 and the second left bottom plate c10 to fall back to the ground; the first motor a4, the second motor c4, and the third motor e4 are started; and so on, so as to convey the material collection box while weighing the material inside.
[0037] The foregoing has shown and described the basic principles, main features and advantages of this utility model. Those skilled in the art should understand that this utility model is not limited to the above embodiments. The embodiments and descriptions in the specification are only illustrative of the principles of this utility model. Various changes and modifications may be made to this utility model without departing from the spirit and scope of this utility model, and all such changes and modifications fall within the scope of this utility model as claimed.
Claims
1. An automatic conveying and weighing device, characterized in that, include: A first main conveyor shaft (a1) and several first slave conveyor shafts (b1); one end of the first main conveyor shaft (a1) is fixedly connected to one end of the first right main rotating shaft (a2); the other end of the first right main rotating shaft (a2) passes through the first right support plate (a3) and is fixedly connected to the output end of the first motor (a4); the first right main rotating shaft (a2) is provided with a first right main rotating gear (a5); the bottom end of the first right support plate (a3) and the first right bottom plate (a6) are fixedly connected; the other end of the first main conveyor shaft (a1) is fixedly connected to one end of the first left main rotating shaft (a7); the other end of the first left main rotating shaft (a7) passes through the first left support plate (a8) and is rotatably connected to the first left support plate (a8); the first left main rotating shaft (a7) is provided with a first left main rotating gear (a9); the bottom end of the first left support plate (a8) and the first left bottom plate (a10) are fixedly connected; one end of the first slave conveyor shaft (b1) is fixedly connected to one end of the first right slave rotating shaft (b2). Connection; the other end of the first right driven rotating shaft (b2) passes through the first right support plate (a3) and is rotatably connected to the first right support plate (a3); the first right driven rotating shaft (b2) is provided with a first right driven rotating gear (b5); the bottom end of the first right support plate (a3) and the first right bottom plate (a6) are fixedly connected; the other end of the first driven conveying shaft (b1) is fixedly connected to one end of the first left driven rotating shaft (b7); the other end of the first left driven rotating shaft (b7) passes through the first left support plate. (a8) is rotatably connected to the first left support plate (a8); the first left driven rotating shaft (b7) is provided with a first left driven rotating gear (b9); the bottom end of the first left support plate (a8) is fixedly connected to the first left base plate (a10); the first right main rotating gear (a5) and several first right driven rotating gears (b5) are all meshed with the first right chain (a11); the first left main rotating gear (a5) and several first left driven rotating gears (b5) are all meshed with the first left chain (a12); A second main conveyor shaft (c1) and several second slave conveyor shafts (d1); two ends of the second main conveyor shaft (c1) are fixedly connected to two ends of the second right main rotating shaft (c2); the other two ends of the second right main rotating shaft (c2) pass through the second right support plate (c3) and are fixedly connected to the output end of the second motor (c4); the second right main rotating shaft (c2) is provided with a second right main rotating gear (c5); the bottom end of the second right support plate (c3) and the second right bottom plate (c6) are fixedly connected; the other two ends of the second main conveyor shaft (c1) are fixedly connected to two ends of the second left main rotating shaft (c7); the other two ends of the second left main rotating shaft (c7) pass through the second left support plate (c8) and are rotatably connected to the second left support plate (c8); the second left main rotating shaft (c7) is provided with a second left main rotating gear (c9); the bottom end of the second left support plate (c8) and the second left bottom plate (c10) are fixedly connected; the two ends of the second slave conveyor shaft (d1) are fixedly connected to the two ends of the second right slave rotating shaft (d2). Connection; the other two ends of the second right driven rotating shaft (d2) pass through the second right support plate (c3) and are rotatably connected; the second right driven rotating shaft (d2) is provided with a second right driven rotating gear (d5); the bottom end of the second right support plate (c3) and the second right bottom plate (c6) are fixedly connected; the other two ends of the second driven conveying shaft (d1) are fixedly connected to the two ends of the second left driven rotating shaft (d7); the other two ends of the second left driven rotating shaft (d7) pass through the second left support plate. (c8) and the second left support plate (c8) are rotatably connected; the second left driven rotating shaft (d7) is provided with a second left driven rotating gear (d9); the bottom end of the second left support plate (c8) is fixedly connected to the second left base plate (c10); the second right main rotating gear (c5) and several second right driven rotating gears (d5) are all meshed with the second right chain (c11); the second left main rotating gear (c5) and several second left driven rotating gears (d5) are all meshed with the second left chain (c12); A third main conveyor shaft (e1) and several third slave conveyor shafts (f1); the three ends of the third main conveyor shaft (e1) are fixedly connected to the three ends of the third right main rotating shaft (e2); the other three ends of the third right main rotating shaft (e2) pass through the third right support plate (e3) and are fixedly connected to the output end of the third motor (e4); the third right main rotating shaft (e2) is provided with a third right main rotating gear (e5); the bottom end of the third right support plate (e3) and the third right bottom plate (e6) are fixedly connected; the third The other three ends of the main conveying shaft (e1) are fixedly connected to the three ends of the third left main rotating shaft (e7); the other three ends of the third left main rotating shaft (e7) pass through the third left support plate (e8) and are rotatably connected to the third left support plate (e8); the third left main rotating shaft (e7) is provided with a third left main rotating gear (e9); the bottom end of the third left support plate (e8) is fixedly connected to the third left bottom plate (e10); the three ends of the third driven conveying shaft (f1) are fixedly connected to the three ends of the third right driven rotating shaft (f2). The third right-hand rotating shaft (f2) is rotatably connected to the third right support plate (e3) at its three ends; the third right-hand rotating shaft (f2) is provided with a third right-hand rotating gear (f5); the bottom end of the third right support plate (e3) is fixedly connected to the third right bottom plate (e6); the other three ends of the third-hand conveying shaft (f1) are fixedly connected to the three ends of the third left-hand rotating shaft (f7); the other three ends of the third left-hand rotating shaft (f7) pass through the third left support plate. (e8) and the third left support plate (e8) are rotatably connected; the third left driven rotating shaft (f7) is provided with a third left driven rotating gear (f9); the bottom end of the third left support plate (e8) and the third left bottom plate (e10) are fixedly connected; the third right main rotating gear (e5) and several third right driven rotating gears (f5) are all meshed with the third right chain (e11); the third left main rotating gear (e5) and several third left driven rotating gears (f5) are all meshed with the third left chain (e12); A top plate (g1) is fixedly installed between the second right support plate (c3) and the second left support plate (c8), and a weight sensor (g2) is installed directly below the top plate (g1); the bottom end of the weight sensor (g2) is fixedly connected to the top ends of several telescopic rods (g3).