Viscous damper

Abstract

The viscous damper comprises a cylinder barrel, an upper end cover and a lower end cover are fixedly arranged at the two ends of the cylinder barrel, a piston and a piston rod are movably arranged in the cylinder barrel, the upper end of the piston rod extends out of the upper end cover, the lower end of the piston rod is fixedly connected with the piston, an inner cavity of the cylinder barrel is divided into a rod cavity and a rodless cavity by the piston, and an energy accumulator is connected outside the cylinder barrel. The piston is provided with a V-shaped flow channel, the rod cavity and the rodless cavity are communicated through the V-shaped flow channel, the hole diameter of the V-shaped flow channel communicated with the rod cavity is smaller than that of the V-shaped flow channel communicated with the rodless cavity, a damping liquid channel communicated with the rodless cavity is arranged in the lower end cover, and the damping liquid channel is communicated with the energy accumulator through a pipeline. The external energy accumulator can prevent the damping liquid from being mixed with the compressible gas, the cavitation phenomenon is avoided, and the volume occupied by the piston rod in the cylinder barrel can be compensated when the piston rod is pressed; hole diameters of the two ends of the V-shaped flow channel are different, and the pulling and pressing force of the viscous damper can be consistent by reasonably setting the hole diameters.

Description

Technical Field

[0001] The utility model relates to the technical field of dampers, in particular to a viscous damper. Background Art

[0002] Viscous dampers are special damping devices that can exhibit unique damping characteristics when subjected to external forces. Compared with traditional friction dampers, viscous dampers have better vibration reduction performance and stability. Therefore, they are widely used in engineering, machinery and other fields. In construction projects, viscous dampers can be used for earthquake resistance and vibration reduction to improve the earthquake resistance of buildings. For example, in large structures such as engineering supports, bridges, towers, etc., viscous dampers can effectively reduce the impact of natural disasters such as wind vibration and earthquakes, ensure structural safety, and extend service life.

[0003] Common viscous dampers are mainly composed of pistons, piston rods, cylinders and seals. The piston divides the inner part of the cylinder into a rod chamber and a rodless chamber. The rod chamber and the rodless chamber are filled with viscous damping liquid as the damping medium. There are small holes on the piston or a gap between the piston and the cylinder to allow the damping medium to pass through. When the piston and the cylinder produce relative motion, the piston will squeeze the damping medium in the chamber on one side of its motion direction. The squeezed damping medium flows to the chamber on the other side through the small holes on the piston or the gap between the piston and the cylinder. The damping medium converts the mechanical energy transmitted from the structure into heat energy and dissipates it during high-speed flow, thereby playing a role in shock absorption, buffering and energy consumption.

[0004] However, when the piston rod is subjected to thrust, the viscous damping liquid in the rodless chamber will produce volume compression or "cavitation" due to the entry or withdrawal of the piston rod. When the piston rod is subjected to thrust, the viscous damping liquid in the rodless chamber will produce volume compression. When the volume entering the piston rod exceeds the compression of the viscous damping liquid, the piston rod will be "stuck". When the piston rod is subjected to tension, part of the volume of the piston rod will leave the cylinder body, and the viscous damping liquid will have "cavitation" or "vacuum", which may easily lead to inconsistent pulling and pressing forces, resulting in unstable performance of the damper, thereby affecting its ability to absorb vibration and shock and reducing the service life of the damper. Therefore, it is necessary to improve it. Utility Model Content

[0005] The purpose of the utility model is to provide a viscous damper in view of the defects and shortcomings of the prior art, which has a simple and reasonable structure, is easy to operate, has consistent pulling and pressing outputs, is not easy to be "stuck", and the damping fluid is not easy to have "cavitation" or "vacuum" phenomena.

[0006] In order to achieve the above purpose, the utility model adopts the following technical solutions:

[0007] A viscous damper described in the utility model comprises a cylinder, wherein the upper and lower ends of the cylinder are respectively fixedly provided with an upper end cover and a lower end cover, a piston and a piston rod are movably provided in the cylinder, the upper end of the piston rod extends out of the upper end cover, and the lower end of the piston rod is fixedly connected to the piston, the piston divides the inner cavity of the cylinder into a rod cavity and a rodless cavity, the cylinder is externally connected to an accumulator, the piston is provided with a V-shaped flow channel which passes through from top to bottom, the rod cavity and the rodless cavity are connected through the V-shaped flow channel, the aperture of the V-shaped flow channel connecting the rod cavity is smaller than the aperture of the V-shaped flow channel connecting the rodless cavity, a damping fluid channel connected to the rodless cavity is provided in the lower end cover, and the damping fluid channel is connected to the accumulator through a pipeline.

[0008] Furthermore, the rodless cavity and the rod cavity are both filled with damping fluid.

[0009] Furthermore, the damping fluid is dimethyl silicone oil.

[0010] Furthermore, the lower end cover is provided with an interface connected to the damping fluid channel, and the accumulator is connected to the interface through a pipeline.

[0011] Furthermore, the accumulator includes a shell and an airbag, an inner cavity is formed inside the shell, the airbag is arranged in the inner cavity, and the damping fluid is stored and released by utilizing the compressibility of the airbag.

[0012] Furthermore, two V-shaped flow channels are provided and are symmetrically arranged along the center of the piston.

[0013] Furthermore, a nut is fixedly connected to the lower end of the piston rod, and the piston and the piston rod are fixedly connected via the nut.

[0014] Furthermore, a flow hole is provided on the lower end cover, and the damping fluid channel is connected with the rodless cavity through the flow hole.

[0015] Furthermore, a connecting piece is provided at the upper end of the piston rod, and the external load is transmitted to the piston rod through the connecting piece.

[0016] Furthermore, the upper end cover and the lower end cover are fixedly connected to the cylinder barrel by bolts.

[0017] The beneficial effects of the utility model are as follows: a viscous damper described in the utility model is provided with an accumulator and a V-shaped flow channel. The external accumulator can prevent the damping fluid and the compressible gas from mixing, thereby avoiding the cavitation phenomenon. The external accumulator can also compensate for the volume occupied by the piston rod in the cylinder when under pressure to adapt to the change of the system volume; the aperture sizes at both ends of the V-shaped flow channel are different, so that the tensile and compressive output forces are different. Reasonable setting of the size can achieve consistent tensile and compressive output forces of the viscous damper, making the performance of the damper more stable, thereby extending the service life of the damper. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram of the overall structure of the utility model;

[0019] Figure 2 It is a schematic diagram of the cross-sectional structure of the utility model without connecting the accumulator;

[0020] Figure 3 yes Figure 2 A schematic diagram of the enlarged structure at A in the middle;

[0021] Figure 4 It is a schematic diagram of the structure of the piston;

[0022] Figure 5 It is a schematic diagram of the cross-sectional structure of the piston;

[0023] Figure 6 It is a structural schematic diagram of the lower end cover.

[0024] Figure 1-6 In: 1. Cylinder barrel; 2. Upper end cover; 3. Lower end cover; 4. Piston; 5. Piston rod; 6. Rod chamber; 7. Rodless chamber; 8. Accumulator; 41. V-shaped flow channel; 10. Pipeline; 11. Nut; 12. Connector; 13. Bolt; 31. Damping fluid channel; 32. Through hole; 33. Interface. DETAILED DESCRIPTION

[0025] The utility model is further described below in conjunction with the accompanying drawings.

[0026] like Figure 1-6The viscous damper shown in the figure comprises a cylinder 1, wherein the upper and lower ends of the cylinder 1 are fixedly provided with an upper end cover 2 and a lower end cover 3 respectively, a piston 4 and a piston rod 5 are movably provided in the cylinder 1, the upper end of the piston rod 5 extends out of the upper end cover 2, and the lower end of the piston rod 5 is fixedly connected to the piston 4. Preferably, in this embodiment, a connecting piece 12 is provided at the upper end of the piston rod 5, and the external load is transmitted to the piston rod 5 through the connecting piece 12, thereby driving the piston 4 and the piston rod 5 to move; the piston 4 divides the inner cavity of the cylinder 1 into a rod cavity 6 and a rodless cavity 7. Preferably, in this embodiment, the rodless cavity 7 and the rod cavity 6 are both filled with damping fluid. Specifically, the damping fluid is dimethyl silicone oil. The viscosity-temperature performance of dimethyl silicone oil is stable, which can ensure that the performance of the damper at different temperatures will not change too much. The dimethyl silicone oil also has shear thinning performance and good compression resistance, so that the dimethyl silicone oil can withstand shear. When the shearing action is applied (shear thinning refers to the phenomenon that the viscosity of the fluid decreases when it is subjected to shearing action, which is more common in non-Newtonian fluids), the viscosity will decrease, which is beneficial to improving the output of the damper; when the dimethyl silicone oil is subjected to compression, the viscosity will increase, which is beneficial to improving the restoring resistance of the damper; the cylinder 1 is externally connected to an accumulator 8, and the piston 4 is provided with a V-shaped flow channel 41 that passes through from top to bottom. The rod chamber 6 and the rodless chamber 7 are connected through the V-shaped flow channel 41. When the damping fluid passes through the V-shaped flow channel 41, a viscous damping force will be generated, which plays a role in vibration reduction. The aperture of the V-shaped flow channel 41 connecting the rod chamber 6 is smaller than the aperture of the V-shaped flow channel 41 connecting the rodless chamber 7. The aperture sizes at both ends of the V-shaped flow channel 41 are different, resulting in different tensile and compressive outputs. Reasonable setting of the aperture size can achieve consistent tensile and compressive outputs of the viscous damper, making the performance of the damper more stable, thereby extending the service life of the damper. See Figure 3 The lower end cover 3 is provided with a damping fluid passage 31 communicating with the rodless chamber 7. Specifically, see Figure 6 The lower end cover 3 is provided with a flow hole 32, and the damping fluid channel 31 is connected with the rodless chamber 7 through the flow hole 32. The damping fluid channel 31 is connected with the accumulator 8 through the pipeline 10. The accumulator 8 can provide additional damping fluid storage and release to achieve volume compensation, thereby ensuring that the damper can operate normally under compression and tension.

[0027] Preferably, in this embodiment, the lower end cover 3 is provided with an interface 33 connected to the damping fluid channel 31, and the accumulator 8 is connected to the interface 33 through a pipeline 10. Specifically, the accumulator 8 includes a shell and an airbag, and an inner cavity is formed inside the shell. The airbag is placed in the inner cavity, and the compressibility of the airbag is used to store and release the damping fluid. When the piston rod 5 pushes the piston 4 downward, part of the damping fluid in the rodless chamber 7 enters the accumulator through the damping fluid channel 31 and the pipeline 10. 8, the piston rod 5 is not prone to "getting stuck", and the pressure in the inner cavity of the accumulator 8 increases, and the gas in the airbag is compressed. When the piston rod 5 is pulled out to drive the piston 4 to move upward, the pressure in the inner cavity decreases, the gas in the airbag expands, and the damping fluid is released to replenish the rodless cavity 7 with damping fluid; the external accumulator 8 can avoid the mixing of the damping fluid and the compressible gas, thereby avoiding the generation of "cavitation" and "vacuum" phenomena, and compensate for the volume occupied by the piston rod 5 in the cylinder 1 when under pressure, so as to adapt to the change of the system volume.

[0028] Regarding the specific structure of the accumulator 8, reference may be made to a bladder accumulator disclosed in a Chinese patent application (publication number: CN114017399A) and a bladder accumulator disclosed in a Chinese patent application (publication number: CN106368991A). In view of the fact that the basic structure / principle of the accumulator 8 has been disclosed in detail in the prior art, it will not be described in detail in this embodiment.

[0029] Preferably, in this embodiment, refer to Figure 5 There are two V-shaped flow channels 41, which are symmetrically arranged along the center of the piston 4, so that the damping fluid can flow through the V-shaped flow channels 41 on both sides of the piston 4, thereby improving work efficiency, and the force on the piston 4 is more uniform, which can reduce the wear of the piston 4 and increase the service life of the piston 4.

[0030] Preferably, in this embodiment, the lower end of the piston rod 5 is fixedly connected with a nut 11, and the piston 4 and the piston rod 5 are fixedly connected by the nut 11. The connection relationship is simple and firm and not easy to loosen, so that the piston 4 and the piston rod 5 are more stable and reliable when subjected to pressure and load.

[0031] Preferably, in this embodiment, the upper end cover 2 and the lower end cover 3 are fixedly connected to the cylinder barrel 1 by bolts 13, so that the upper end cover 2 and the lower end cover 3 are not easily separated from the cylinder barrel 1, which has the advantages of simple structure, stable and reliable connection, and easy maintenance.

[0032] The working principle of the utility model is as follows: when the external load is large, the piston rod 5 is forced to drive the piston 4 downward, the pressure in the rodless chamber 7 increases, and part of the damping fluid in the rodless chamber 7 enters the rod chamber 6 through the V-shaped flow channel 41, generating a viscous damping force, which plays a role in vibration reduction. Part of the damping fluid in the rodless chamber 7 also enters the accumulator 8 through the damping fluid channel 31 and the pipeline 10, and increases the pressure in the inner cavity of the accumulator 8, and the gas in the airbag is compressed, which plays a role in storing the damping fluid, and the piston rod 5 is not prone to "sticking". When the external load is small and the piston rod 5 is not enough to overcome the pressure in the rodless chamber 7, the piston rod 5 pulls out the piston 4 and moves upward, and the pressure in the rodless chamber 7 decreases, and part of the damping fluid in the rod chamber 6 enters the rodless chamber 7 through the V-shaped flow channel 41, generating a viscous damping force, which plays a role in vibration reduction, and reduces the pressure in the inner cavity of the accumulator 8, the gas in the airbag expands, releasing the damping fluid, and The chamber 7 replenishes the damping fluid; the external accumulator 8 can prevent the damping fluid and the compressible gas from mixing, thereby avoiding the generation of "cavitation" and "vacuum" phenomena, and compensate for the volume occupied by the piston rod 5 in the cylinder 1 when under pressure to adapt to the change in the system volume. When the airbag is compressed, if its speed needs to be consistent with the movement speed of the piston 4, the damping output also needs to be larger and larger. When the airbag is released, if its speed needs to be consistent with the movement speed of the piston 4, basically the piston 4 movement accumulator 8 assists to ensure that the speeds of the two are consistent, so that the tension and compression outputs of the damper are inconsistent, the aperture sizes at both ends of the V-shaped flow channel 41 are different, and the aperture of the V-shaped flow channel 41 connecting to the rod chamber 6 is smaller than the aperture of the V-shaped flow channel 41 connecting to the rodless chamber 7, so that the tension and compression outputs are different. Reasonable setting of its size can achieve consistent tension and compression outputs of the viscous damper, making the performance of the damper more stable, thereby extending the service life of the damper.

[0033] The above description is only a preferred embodiment of the present utility model, so all equivalent changes or modifications made according to the structure, features and principles described in the scope of the present utility model patent application are included in the scope of the present utility model patent application.

Claims

1. A viscous damper, comprising a cylinder (1), wherein an upper end cover (2) and a lower end cover (3) are fixedly provided at the upper and lower ends of the cylinder (1), respectively, a piston (4) and a piston rod (5) are movably provided in the cylinder (1), the upper end of the piston rod (5) protrudes from the upper end cover (2), the lower end of the piston rod (5) is fixedly connected to the piston (4), the piston (4) divides the inner cavity of the cylinder (1) into a rod cavity (6) and a rodless cavity (7), characterized in that: The cylinder (1) is externally connected to an accumulator (8); the piston (4) is provided with a V-shaped flow channel (41) that passes through from top to bottom; the rod chamber (6) and the rodless chamber (7) are connected via the V-shaped flow channel (41); the diameter of the hole connecting the V-shaped flow channel (41) and the rod chamber (6) is smaller than the diameter of the hole connecting the V-shaped flow channel (41) and the rodless chamber (7); a damping fluid channel (31) connected to the rodless chamber (7) is provided inside the lower end cover (3); the damping fluid channel (31) is connected to the accumulator (8) via a pipeline (10).

2. A viscous damper according to claim 1, characterized in that: The rodless cavity (7) and the rod cavity (6) are both filled with damping fluid.

3. A viscous damper according to claim 2, characterized in that: The damping fluid is dimethyl silicone oil.

4. A viscous damper according to claim 1, characterized in that: The lower end cover (3) is provided with an interface (33) that is in communication with the damping fluid channel (31), and the accumulator (8) is connected to the interface (33) via a pipeline (10).

5. A viscous damper according to claim 2, characterized in that: The accumulator (8) comprises a shell and an air bag. An inner cavity is formed inside the shell. The air bag is arranged in the inner cavity. The compressibility of the air bag is used to store and release the damping fluid.

6. A viscous damper according to claim 1, characterized in that: Two V-shaped flow channels (41) are provided and are symmetrically arranged along the center of the piston (4).

7. A viscous damper according to claim 1, characterized in that: The lower end of the piston rod (5) is fixedly connected with a nut (11), and the piston (4) and the piston rod (5) are fixedly connected via the nut (11).

8. The viscous damper according to claim 1, characterized in that: The lower end cover (3) is provided with a flow hole (32), and the damping fluid channel (31) is connected to the rodless chamber (7) through the flow hole (32).

9. A viscous damper according to claim 1, characterized in that: The upper end of the piston rod (5) is provided with a connecting piece (12), and external loads are transmitted to the piston rod (5) through the connecting piece (12).

10. The viscous damper according to claim 1, characterized in that: The upper end cover (2) and the lower end cover (3) are both fixedly connected to the cylinder barrel (1) via bolts (13).

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