Pneumatic parallelogram balance mechanism for power assisting device

Abstract

The utility model relates to a pneumatic parallelogram balance mechanism for a power assisting device. The pneumatic parallelogram balance mechanism comprises a supporting stand column, a fixed rotating stand column, a rotating arm, a rotating auxiliary arm, an air cylinder, a sliding block, a sliding shaft, a movable rotating stand column, a load suspension arm and a pneumatic control system. The fixed rotating stand column can rotate by 360 degrees in the horizontal direction, the axes of the fixed rotating stand column, the rotating arm, the air cylinder (including the axis extension line) and the movable rotating stand column form a parallelogram, and static balance of any position of a load workpiece in the vertical direction and the horizontal direction is achieved. Therefore, the workpiece can move and rotate in any direction in the space and is always in a suspension state. Static balance at any position of a workpiece space can be achieved, follow-up stop can be achieved, and the follow-up stop device is simple in structure, high in reliability, low in cost, capable of being applied to movable or fixed balance cranes, adjustment, butt joint and installation assisting devices on production lines, carrying devices and the like and high in practicability and universality.

Description

Technical Field

[0001] This utility model relates to the fields of pneumatic technology and mechanical manufacturing, and to pulsed or continuous production lines such as aircraft and automobile assembly, and in particular to a pneumatic parallelogram balancing mechanism for power-assisted devices. Background Technology

[0002] In aircraft manufacturing, many large components require handling, docking, and assembly. Lacking a simple, low-cost, and versatile assistive device, workshops mostly rely on traditional manual handling and hoisting methods. For example, aircraft doors are heavy and cannot be installed manually. Current door assembly methods in workshops involve hoisting, which is difficult to position, has poor accuracy, low safety, requires many operators, is time-consuming and labor-intensive, and has low production efficiency. Furthermore, a typical factory building only has one or two cranes, which are used very frequently, requiring queuing for crane use during door installation.

[0003] Besides aircraft doors, it can also be widely used in the assembly and handling of aircraft hatches, spans, skins, hinges, etc. There is also a demand for assistive devices on automobile assembly lines and various machining production lines.

[0004] Commonly used power-assist devices have cylinders with hinged ends, resulting in complex connection structures and numerous connecting parts. The force provided by the cylinder to the balancing mechanism needs to be transmitted to the parallelogram of connecting rods. During cylinder debugging, errors are significant, making it difficult to achieve complete static balance within the theoretically desired range of motion. Manual micro-force assistance is required when the workpiece stops in mid-air. Common power-assist devices cannot achieve complete force balance; differences exist between the assistance and load weight at different angles and positions, leading to stability and safety issues for the entire device. This makes them unsuitable for assembly and docking processes requiring high stability, such as hatch installation. Furthermore, existing power-assist devices are mostly specialized, lacking versatility and incurring high operating costs. Utility Model Content

[0005] The purpose of this application is to provide a pneumatic parallelogram balancing mechanism for an assistive device. Specifically, it is achieved by cleverly combining pneumatic components with mechanical structures and utilizing the principles of parallelogram force balance and similar triangles. The cylinder directly forms one side of the parallelogram in the force balance, avoiding errors in the force transmission process and truly realizing the balance of the mechanical structure under no-load and load conditions. This enables the workpiece to be handled with ease, docked, and flexibly assembled.

[0006] A pneumatic parallelogram balancing mechanism for an assistive device includes a support column, a fixed rotating column, a rotating arm, a rotating auxiliary arm, a cylinder, a sliding shaft, a slider, a movable rotating column, a load suspension arm, and a pneumatic control system. The support column can be vertically mounted on a fixed or movable platform. The fixed rotating column is mounted on the support column and can rotate 360° horizontally. One end of the rotating arm, one end of the rotating auxiliary arm, and the end of the cylinder piston rod are respectively fixed to three shafts on the fixed rotating column. The sliding shaft is fixed to the rotating arm, and the slider is fixed to the end cap of the cylinder. The cylinder end moves along the sliding shaft following the slider. The movable rotating column is connected to the other end of the rotating arm and the rotating auxiliary arm, and can move up, down, left, and right in space following the rotating arm and the auxiliary arm. The load suspension arm is fixed to the movable rotating column and can rotate around it. The pneumatic control system is used to adjust and switch the cylinder thrust (or pull). Ultimately, this structure can achieve static balance of the load product at any position, thereby completing functions such as installation, docking, and handling.

[0007] The axes of the fixed rotating column, rotating arm, cylinder (including the axis extension line), and movable rotating column can always form a parallelogram structure. This structure can rotate around the supporting column, and the load suspension arm can also rotate around the movable rotating column of this structure.

[0008] When the load suspension arm is not loaded with any load, at any two positions in space, the two lever arms (L1 and L2) of the cylinder thrust (or pull) and the two lever arms (l1 and l2) of the gravity formed by the load suspension arm are proportional, that is, L1 / l1=L2 / l2.

[0009] When the load suspension arm is loaded with any fixed load within a certain range, at any two positions in space, the two lever arms (L1 and L2) of the cylinder thrust (or pull) and the two lever arms (l1 and l2) of the gravity formed by the load suspension arm and the load together have a proportional relationship, that is, L1 / l1=L2 / l2.

[0010] The cylinder thrust (or pull) can be adjusted through the pneumatic control system so that the cylinder thrust (or pull) torque is equal to the load torque (including the load suspension arm) at any position in space, so that the load reaches a static equilibrium state without external interference.

[0011] The mechanical force analysis is as follows:

[0012] According to the principle of force balance:

[0013] G·l2=F2·L2 ①

[0014] G·l1=F1·L1 ②

[0015] From ① and ② we get

[0016] F2=G·l2 / L2

[0017] F1=G·l1 / L1

[0018] Because △CED is similar to △ABC

[0019] Therefore, AC / CD = AB / CE

[0020] Because AC = A'C = l2, CD = L2, AB = l1, CE = L1

[0021] Therefore, l2 / L2 = l1 / L1

[0022] Therefore, F2 / F1=(G·l2 / L2) / (G·l1 / L1)=(l2 / L2) / (l1 / L1)=1

[0023] That is, F1 and F2 are always equal at any rotational position, indicating that under no-load or constant load (i.e., G is constant), force balance at any position can be achieved by matching and adjusting the cylinder thrust (or pull) F1 (F2) by the control system.

[0024] Based on force analysis, the balancing method simplifies to providing a stable cylinder output force to match the load gravity. To meet diverse usage requirements, multiple sets of precision pressure regulating valves are installed, using logic control and gear switching to achieve output pressure variations. These include a 0-10 bar adjustable stepless output, multiple preset load outputs, and an unloaded output. This setup enables the rapid assembly or handling of multiple fixed-weight loads on the production line, while also accommodating the assembly and handling of any temporarily added load within the specified limit (a maximum limit exists depending on the cylinder diameter).

[0025] The support column can be fixed at the bottom or at the top. When the support column is installed vertically and fixed at the bottom (i.e., the fixed rotating column is installed above the support column), the cylinder should generate thrust, and air should be introduced into the rear chamber of the cylinder for pressure control. When the support column is rotated 180° and vertically hoisted (i.e., the top is fixed and the fixed rotating column is installed below the support column), the cylinder should generate pull force, and air should be introduced into the front chamber of the cylinder for pressure control.

[0026] Compared with existing technologies, this utility model utilizes a combination of parallelogram force balance and similar triangle principles. Through independent research and development of the assisted balance principle, structural design, and aerodynamic control principle, it achieves the lifting, lowering, and movement of workpieces of different sizes and shapes. The structure is simple and stable, highly reliable, low-cost, and widely applicable. It has high tolerance for clamps behind the load-bearing suspension arm and can be used with various types of clamps, possessing high practicality and versatility. For example, the application of this structure changes the traditional manual installation method of cabin doors, reducing the number of installers from multiple people to one person, greatly reducing labor costs and improving installation efficiency. It has universal applicability to the assisted dynamic flexible installation of similar aircraft cabin door structures with small curvature variations and similar dimensions. It is a universal, inexpensive, efficient, and precise assembly structure and method with significant technical and market application value. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of a pneumatic parallelogram balancing mechanism for an assistive device.

[0028] Figure 2 Schematic diagram of a fixed rotating column structure;

[0029] Figure 3 This is a schematic diagram of a movable rotating column structure;

[0030] Figure 4 This is a schematic diagram of a parallelogram structure;

[0031] Figure 5 This is a simplified diagram of structural mechanics (position 1);

[0032] Figure 6 This is a simplified structural mechanics diagram (position 2);

[0033] Numbering in the diagram: 1. Support column; 2. Fixed rotating column; 3. Rotating arm; 4. Rotating auxiliary arm; 5. Cylinder; 6. Sliding shaft; 7. Slider; 8. Moving rotating column; 9. Load suspension arm; 10. Pneumatic control system; 11. Rotating shaft; 12. Rotating bearing; 13. Rotating support base; 14. Hollow cylindrical structure; 15. Through-hole connecting plate; 16. Cube plate; 17. Side plate; 18. Rotating auxiliary arm rotating shaft; 19. Tapered roller bearing; 20. Rectangular tube structure; 21. Cube block; 22. Rectangular tube; 23. Cube block Detailed Implementation

[0034] The present invention will now be described in further detail with reference to the accompanying drawings.

[0035] See Figures 1-6A pneumatic parallelogram balancing mechanism and balancing method for an assistive device includes a support column 1, a fixed rotating column 2, a rotating arm 3, a rotating auxiliary arm 4, a cylinder 5, a sliding shaft 6, a slider 7, a movable rotating column 8, a load suspension arm 9, and a pneumatic control system 10.

[0036] The support column 1 can be vertically installed on a fixed or movable platform. The fixed rotating column 2 is installed on the support column and can rotate 360° horizontally. One end of the rotating arm 3 and the rotating auxiliary arm 4 and the end of the cylinder piston rod are respectively fixed on the three shafts of the fixed rotating column 2. The sliding shaft 6 is fixed on the rotating arm 3. The slider 7 is fixed on the end cap of the cylinder 5. The end of the cylinder 5 moves on the sliding shaft 6 following the slider 7. The movable rotating column 8 is connected to the other end of the rotating arm 3 and the rotating auxiliary arm 4. The movable rotating column 8 can move up, down, left, and right in space with the rotating arm 3 and the auxiliary arm 4. The load suspension arm 9 is fixed on the movable rotating column 8 and can rotate around the movable rotating column 8. The pneumatic control system 10 is used to adjust and switch the cylinder thrust (or pull).

[0037] The fixed rotating column 2 includes a rotating support base 13, a rotating bearing 12, and a rotating shaft 11. The rotating support base 13 is fixed on the supporting column 1, and the rotating shaft 11 is mounted on the rotating support base 13 through the rotating bearing 12.

[0038] The movable rotating column 8 is composed of a hollow cylindrical structure 14, a through-hole connecting plate 15, a cubic plate 16, a side plate 17, a rotating auxiliary arm rotating shaft 18, and a tapered roller bearing 19. A tapered roller bearing 19 is installed at each of the upper and lower ends of the hollow cylindrical structure 14. The through-hole connecting plate 15 is a rectangular plate with through holes on the upper and lower surfaces. The two through-hole connecting plates 15 are symmetrically fitted onto the hollow cylindrical structure 14 and welded together. The cubic plate 16 is vertically welded to the bottom surface of the two through-hole connecting plates 15. Two rotating shaft through holes are evenly distributed on the surface of the side plate 17. The rotating auxiliary arm rotating shaft 18 passes through the rotating shaft through holes. The two side plates 17 are vertically welded along the boundary of the cubic plate 16.

[0039] The rotating arm 3 consists of a rectangular tube structure 20 and a cube 21. The rectangular tube structure 20 has a through hole for fixing the sliding shaft 6. Cubes 21 with symmetrical stepped holes are welded to both ends. Ball bearings are symmetrically installed in the stepped holes of the cubes 21. One end is connected to the rotating shaft 11 in the fixed rotating column 2, and the other end is connected to the rotating shaft 18 of the auxiliary rotating arm. The rotating auxiliary arm 4 consists of a rectangular tube 22 and a cube 23. Cubes 23 with stepped holes are welded to both ends of the rectangular tube 22. Ball bearings are symmetrically installed in the stepped holes. The two rotating auxiliary arms 4 are placed parallel to each other, one end connected to the rotating shaft 11 in the fixed rotating column 2, and the other end connected to the rotating shaft 18 of the auxiliary rotating arm. The slider 7 is a cube with symmetrical stepped through holes on its upper and lower end faces and bolt holes at the four corners of its side end face. It is connected to the cylinder 5 by bolts. A linear bearing is installed between the slider 7 and the sliding shaft 6 to achieve low-friction, high-precision linear motion.

[0040] The parallelogram structure consists of a fixed rotating column 2, a rotating arm 3, a cylinder 5 (including its axis extension), and the axis of a movable rotating column 8. The pneumatic control system 10 adjusts the thrust (or pull) of cylinder 5 to ensure that the thrust (or pull) torque of cylinder 5 is equal to the torque of the load (including the load suspension arm 9) at any position in space. This allows the load to reach a static equilibrium state without external interference, achieving static balance of the workpiece at any position (up, down, left, or right). The fixed rotating column 2 can rotate 360° horizontally, and the load suspension arm 9 can rotate around the movable rotating arm 8, thus enabling the workpiece to move and rotate in any direction in space while remaining in a suspended state.

[0041] A corresponding clamping fixture is designed according to the specific structure of the workpiece and is connected to the load suspension arm 9. The load is determined based on the total weight of the workpiece and the fixture, thereby determining the thrust (or pull) of the cylinder 5, which is achieved by adjusting the precision pressure reducer in the pneumatic control system 10. This utility model can be used for multiple different workpieces; simply switch the fixture and readjust the pressure reducer to meet the requirements of versatility.

Claims

1. A pneumatic parallelogram balancing mechanism for an assistive device, characterized in that... It includes a support column (1), a fixed rotating column (2), a rotating arm (3), a rotating auxiliary arm (4), a cylinder (5), a sliding shaft (6), a slider (7), a movable rotating column (8), a load suspension arm (9), and a pneumatic control system (10). The support column (1) is vertically installed on a fixed or movable platform. The fixed rotating column (2) is installed on the support column and can rotate 360° horizontally. One end of the rotating arm (3) and the rotating auxiliary arm (4) and the piston rod end of the cylinder (5) are respectively fixed on the three shafts of the fixed rotating column (2). The sliding shaft (6) is fixed on the rotating arm (3). The slider (7) is fixed on the end cap of the cylinder (5). The end of the cylinder (5) moves on the sliding shaft (6) following the slider (7). The movable rotating column (8) is connected to the other end of the rotating arm (3) and the rotating auxiliary arm (4). The movable rotating column (8) can move up, down, left, and right in space with the rotating arm (3) and the auxiliary arm (4). The load suspension arm (9) is fixed on the movable rotating column (8) and can rotate around the movable rotating column (8). The pneumatic control system (10) is used to adjust and switch the cylinder thrust or pull.

2. The pneumatic parallelogram balancing mechanism for an assistive device according to claim 1, characterized in that, The axes of the fixed rotating column (2), rotating arm (3), cylinder (5) and moving rotating column (8) always form a parallelogram structure. This structure can rotate around the supporting column (1), and the load suspension arm (9) can also rotate around the moving rotating column (8) of this structure.

3. A pneumatic parallelogram balancing mechanism for an assistive device according to claim 2, characterized in that, When the load suspension arm (9) is not loaded with any load, at any two positions in space, the two lever arms L1 and L2 of the thrust or pull force of the cylinder (5) and the two lever arms l1 and l2 of the gravity formed by the load suspension arm (9) have a proportional relationship: L1 / l1=L2 / l2.

4. A pneumatic parallelogram balancing mechanism for an assistive device according to claim 3, characterized in that, When the load suspension arm (9) is loaded with a fixed load within a certain range, at any two positions in space, the two force arms L1 and L2 of the cylinder (5) thrust or pull force and the two force arms l1 and l2 of the gravity formed by the load suspension arm and the load have a proportional relationship: L1 / l1=L2 / l2.

5. A pneumatic parallelogram balancing mechanism for an assistive device according to claim 4, characterized in that, The pneumatic control system (10) adjusts the thrust or pull of the cylinder so that the thrust or pull torque of the cylinder (5) is equal to the load torque at any position in space, so that the load reaches a static equilibrium state without external interference.

6. A pneumatic parallelogram balancing mechanism for an assistive device according to claim 5, characterized in that, The pneumatic control system (10) can achieve stepless pressure regulation from 0 to 10 bar through a precision pressure regulating valve, thereby changing the output force of the cylinder (5) to adapt to different load weights; multiple sets of precision pressure regulating valves can also be added to achieve multi-level adjustment and realize the switching between multiple fixed levels and stepless levels.

7. A pneumatic parallelogram balancing mechanism for an assistive device according to claim 6, characterized in that, When the support column (1) is installed vertically and fixed at the bottom, the cylinder (5) generates thrust, and air enters the rear chamber of the cylinder (5) for pressure control; when the support column (1) is rotated 180° and vertically suspended and fixed at the top, the cylinder (5) generates pull, and air enters the front chamber of the cylinder (5) for pressure control.

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