Hydraulic viscous inertial damper

Abstract

The invention discloses a hydraulic viscous inertial damper, and belongs to the technical field of damping. Comprising an inertial unit and a viscous damper unit. The inertial unit comprises a hydraulic driving device, a mass block and a hydraulic pipeline. The viscous damper comprises a lug plate, a piston rod, an end cover, a piston, a cylinder barrel and a connecting cylinder barrel. The hydraulic driving device is connected with the viscous damper through the connecting plate, the hydraulic pipeline is communicated with an oil port of the viscous damper and an oil port of the hydraulic driving device, and a fluid medium forms a loop between the hydraulic driving device and the damper. When the damper generates displacement under the action of an external load, silicone oil in a cavity of the damper enters one oil port of the hydraulic driving device through a pipeline, so that the hydraulic driving device is driven to rotate in one direction, the hydraulic driving device rotates to drive the mass block to rotate, the mass block is equivalent to a flywheel, and the mass block is driven to rotate in the other direction under small excitation. And large inertia force can be provided, the inertia damping force of the whole system is improved, and the energy consumption efficiency is further improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of shock absorption, and more specifically, relates to a hydraulic viscous inertial damper. Background Art

[0002] As an important load-bearing component of a cable-stayed bridge, the cable has the characteristics of high flexibility and low inherent damping. Under external excitation, it is easy to cause vortex-induced resonance, parametric resonance, wind-rain induced vibration and other problems. In order to suppress the vibration of the cable, various vibration reduction measures are taken in large-span cable-stayed bridges. Among them, the method of adding external mechanical damping can directly increase the modal damping of the cable, which is a commonly used method in cable vibration reduction. However, conventional external mechanical damping is limited by the performance of the damper, and it is often difficult to achieve ideal control effects in multi-modal control of longer cables.

[0003] In existing research, people have found that additional mass can make damping consume more energy and achieve a larger modal damping ratio. By utilizing various mechanical amplification mechanisms (existing ones such as gear racks, ball screws, lever pendulums, etc.), it is possible to use smaller mass objects (such as flywheel masses) to produce a large equivalent mass effect, realize the "quasi-negative stiffness" feature of the damper hysteresis curve, greatly increase the stroke of the damper, and improve energy efficiency and vibration reduction performance. Therefore, inertial dampers have gradually begun to be used in structural vibration control.

[0004] However, the currently commonly used ball screw structure inertial damper has disadvantages such as non-compact installation space, many parts, high friction, easy wear of the balls, and difficult maintenance, which restricts its application scenarios. Summary of the invention

[0005] In view of the defects of the prior art, the purpose of the present invention is to provide a hydraulic viscous inertial damper, aiming to achieve the technical problem of obtaining a higher inertial damping force at low speed with a more compact structure.

[0006] To achieve the above-mentioned object, the present invention provides a hydraulic viscous inertial damper, comprising an inertial unit and a viscous damper unit. The viscous damper unit comprises a viscous damper, and the inertial unit comprises a mass block, a hydraulic drive device, a hydraulic pipeline, etc. The hydraulic drive device is connected to the viscous damper through a connecting plate, and the hydraulic pipeline is connected to the oil port of the viscous damper and the oil port of the hydraulic drive device respectively, and the fluid medium forms a loop between the hydraulic drive device and the viscous damper;

[0007] The mass block is mechanically connected to the output shaft of the hydraulic drive device and rotates along with the rotation of the hydraulic drive device.

[0008] The viscous damper is mainly composed of ear plates, piston rods, end covers, pistons, cylinders, connecting cylinders, etc.

[0009] When the damper is displaced by external load, the silicone oil in the damper cavity enters one of the oil ports of the hydraulic drive device through the pipeline, thereby driving the hydraulic drive device to rotate in one direction. The rotation of the hydraulic drive device will drive the mass block to rotate. The mass block is equivalent to a flywheel. Under a smaller excitation, it can provide a larger inertial force, thereby increasing the inertial damping force of the entire system and further fully improving the energy consumption efficiency.

[0010] Preferably, the piston and the piston rod are an integrated structure.

[0011] Preferably, a sealing member is mounted on the piston.

[0012] Preferably, the hydraulic pipeline is a hose.

[0013] Preferably, the mass block is a cylindrical mass block.

[0014] Compared with the prior art, the above technical solutions conceived by the present invention can achieve the following

[0015] Beneficial effects:

[0016] 1. The present invention replaces the ball screw inertial structure with a hydraulically driven inertial unit. The ball screw structure is a structure in which metal balls are arranged in the thread as a transmission structure. This structure requires very high processing accuracy, and as the balls wear, the friction of the inertial unit will become greater and greater. The present invention adopts a hydraulically driven inertial unit, and the wear can be ignored. At the same time, the flywheel is directly driven by hydraulic pressure, and there is no need to add metal balls as an additional transmission structure like a ball screw structure. Therefore, the friction is greatly reduced, so that a higher inertial damping force can be obtained at low speeds.

[0017] 2. Compared with ball screw inertia, the hydraulic drive structure widely used in engineering replaces the method of filling metal steel balls in the thread, which greatly simplifies the structure of the inertia unit and reduces the production cost. At the same time, the hydraulic unit is very easy to maintain, and the hydraulic oil can be easily replaced by hydraulic hose. At the same time, the flywheel is placed outside, so it is also very easy to replace the flywheel, which greatly reduces the maintenance cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is the principle diagram of the inertial damper of the present invention.

[0019] Figure 2 Hysteresis curves of the damper under different speed indexes.

[0020] Figure 3 It is a schematic diagram of the overall structure of the inertial damper of the present invention.

[0021] Figure 4It is a schematic diagram of the structure of the viscous damper of the present invention.

[0022] Figure 5 This is a prototype experiment diagram of the present invention.

[0023] Figure 6 It is the hysteresis curve measured under different working conditions of the present invention.

[0024] Reference numerals:

[0025] 1-viscous damper, 2-mass block, 3-hydraulic drive device, 4-hydraulic pipeline, 5-connecting plate, 1.1-ear plate, 1.2-piston rod, 1.3-end cover, 1.4-first chamber, 1.5-piston, 1.6-cylinder, 1.7-second chamber, 1.8-connecting cylinder. DETAILED DESCRIPTION

[0026] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0027] At present, viscous dampers mainly use high-viscosity silicone oil as filling material. For gap dampers, the functional relationship between force and velocity is F = cv α Since the speed index α is only related to the type of silicone oil, silicone oils with different viscosities exhibit different damping forces when the damper acts. The common feature is that the damping force is low at low speeds.

[0028] In order to solve the problem of low damping force at low speed, the present invention combines the viscous damping characteristics with the inertial force characteristics of the mass block by setting an inertial unit, and increases the damping force through the inertial mechanics amplification principle of the mass block, thereby increasing the damping force under low-speed conditions; and under high-speed action, due to the dilution of the silicone oil medium, the influence of the shear damping force is correspondingly reduced, thereby satisfying a better constitutive relationship curve for the full speed range from low speed to high speed. The principle diagram of the present invention is shown in the figure below. Figure 1 As shown, the relationship between the damping force F and the speed v is:

[0029]

[0030] Where c is the damping coefficient, which is related to the viscous damping material; m e is the inertia coefficient; is the acceleration; α is the velocity index. When α is not equal to 1.0, the damper is a nonlinear damper. The velocity index can be adjusted by using different types of silicone oil. Under different velocity indexes, the force displacement curve of the damper is as follows: Figure 2 shown.

[0031] Comparison of the hysteresis curves of the damper under different speed indexes ( Figure 2 ) It can be seen that the viscous inertial damper (α<1.0) with nonlinear viscous damping has a greater output, a fuller hysteresis curve, and a stronger energy dissipation capacity. In addition, the presence of inertia also makes the hysteresis curve of the damper present a quasi-negative stiffness characteristic, which is beneficial to improving the vibration control effect of the damper on the cable.

[0032] Using the above principle, the present invention designs a liquid driven inertial damper, such as Figure 3 As shown, it includes a viscous damper 1, a mass block 2, a hydraulic drive device 3, a hydraulic pipeline 4 and a connecting plate 5. The hydraulic drive device 3 is connected to the viscous damper 1 through the connecting plate 5 to form a whole, and the hydraulic pipeline 4 is connected to the oil port of the viscous damper 1 and the oil port of the hydraulic drive device 3 respectively, and the fluid medium forms a loop between the hydraulic drive device 3 and the viscous damper 1;

[0033] The mass block 2 is mechanically connected to the output shaft of the hydraulic drive device 3 and rotates along with the rotation of the hydraulic drive device 3 .

[0034] The viscous damper 1 comprises an ear plate 1.1, a piston rod 1.2, an end cover 1.3, a piston 1.5, a cylinder 1.6, a connecting cylinder 1.8, etc. Figure 4 shown.

[0035] The cylinder 1.6 is provided with end covers 1.3 at both ends. The piston rod 1.2 is located in the cylinder 1.6, and the two ends extend from the end covers 1.3, one end of which is fixed to the ear plate 1.1, and the other end is located in the space formed by the cylinder 1.6 and the connecting cylinder 1.8, and the connecting cylinder 1.8 is fixed to the other ear plate 1.1. The piston 1.5 is fixed in the middle of the piston rod 1.2, and the piston 1.5 is located in the cylinder 1.6 to divide it into a first chamber 1.4 and a second chamber 1.7. The first chamber 1.4 and the second chamber 1.7 are both provided with oil ports, and the first chamber 1.4 is connected to the oil inlet A of the hydraulic drive device 3 through the hydraulic pipeline 4, and the second chamber 1.7 is connected to the oil inlet B of the hydraulic drive device 3 through the hydraulic pipeline 4. The silicone oil in the first chamber 1.4 or the second chamber 1.7 of the damper flows into the hydraulic drive device 3 through the hydraulic pipeline 4, thereby driving the hydraulic drive device 3 to rotate, and at the same time driving the mass block 2 to rotate together.

[0036] In the above scheme, the masses of the hydraulic drive device 3 and the mass block 2 can be configured according to the actual project requirements. A suitable hydraulic drive device 3 and mass block 2 can better achieve the damping performance of the inertial damper. And by replacing silicone oils of different viscosities, the damper can have different speed indexes α.

[0037] The present invention has been tested on a prototype. Figure 5 As shown. The force-displacement hysteresis curve of the prototype is obtained by dynamic cycle loading, as shown Figure 6 The parameters of the four test conditions are shown in Table 1. From the figure, we can see the obvious quasi-negative stiffness characteristics, and the hysteresis curve is relatively full, which means that the damping energy dissipation capacity is improved. The experimental results illustrate the positive impact of introducing inertia.

[0038] Table 1

[0039]

[0040] It will be easily understood by those skilled in the art that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A hydraulic viscous inertial damper, characterized in that: The invention comprises an inertial unit and a viscous damping unit, wherein the viscous damping unit comprises a viscous damper (1), the inertial unit comprises a mass block (2), a hydraulic drive device (3) and a hydraulic pipeline (4), the hydraulic drive device (3) is connected to the viscous damper (1), the hydraulic pipeline (4) respectively connects the oil port of the viscous damper (1) and the oil port of the hydraulic drive device (3), and the fluid medium forms a loop between the hydraulic drive device (3) and the viscous damper (1); The mass block (2) is connected to the output shaft of the hydraulic drive device (3) and rotates along with the rotation of the hydraulic drive device (3).

2. The hydraulic viscous inertial damper according to claim 1, characterized in that: The viscous damper (1) comprises an ear plate (1.1), a piston rod (1.2), an end cover (1.3), a piston (1.5), a cylinder (1.6), and a connecting cylinder (1.8). The cylinder (1.6) is provided with end covers (1.3) at both ends. The piston rod (1.2) extends from the end covers (1.3) at both ends, one end of which is fixed to the ear plate (1.1), and the other end is located in a space formed by the connection of the cylinder (1.6) and the connecting cylinder (1.8). The other ear plate (1.1) is fixed; a piston (1.5) is fixed in the middle of the piston rod (1.2); the piston (1.5) is located in the cylinder barrel (1.6) to divide it into a first chamber (1.4) and a second chamber (1.7); oil ports are provided at both ends of the cylinder barrel (1.6); the first chamber (1.4) is connected to an oil inlet A of a hydraulic drive device (3) through a hydraulic pipeline (4); and the second chamber (1.7) is connected to an oil inlet B of the hydraulic drive device (3) through a hydraulic pipeline (4).

3. The hydraulic viscous inertial damper according to claim 2, characterized in that: The first chamber (1.4) comprises a first oil port, which is communicated with an oil inlet A; the second chamber (1.7) comprises a second oil port, which is communicated with an oil inlet B.

4. The hydraulic viscous inertial damper according to claim 2, characterized in that: The piston (1.5) and the piston rod (1.2) are of an integrated structure.

5. The hydraulic viscous inertial damper according to claim 1, characterized in that: A sealing member is sleeved on the piston (1.5).

6. The hydraulic viscous inertial damper according to claim 1, characterized in that: The hydraulic pipeline (4) is a hose.

7. The hydraulic viscous inertial damper according to claim 1, characterized in that: The mass block (2) is a cylindrical mass block.

Images