CN108006144B - speed damper - Google Patents

Abstract

The invention discloses a speed damper, the inner cavity of the cylinder body is divided into a first cavity and a second cavity in the axial direction by a partition body, and a central via hole is opened on the partition body; A first piston in a cavity and a second piston in a second cavity; the piston rod includes a first piston rod connected to the first piston and a second piston rod connected to the second piston, the first There is a given connection strength between the piston and the first piston rod; wherein, the diameter of the second cavity is greater than the diameter of the first cavity; the first piston rod passes through the cylinder and is connected with the corresponding bridge support; During the stroke, the first piston rod is disengaged from the second piston rod, and engages with the second piston rod in the central through hole when the first piston reaches the side dead center where the second cavity is located. According to the present invention, both small vibration buffering and relatively large vibration buffering can be satisfied.

Description

speed damper

technical field

The invention relates to a speed damper, which is a speed damper used on a bridge support.

Background technique

The speed damper is usually used in conjunction with the bridge support. The structure of the existing speed damper is that a special oil cylinder is injected with a viscous liquid based on silicone as the force transmission medium (denoted as damping medium). The cylinder wall and There is a gap between the pistons, or a damping hole is opened on the piston for the flow of the viscous liquid. Since the internal friction coefficient of the viscous liquid is relatively large, energy consumption is generated based on its flow damping. Furthermore, when the velocity damper is impacted by an external load, the piston rod drives the piston to move in the liquid cylinder, and the damping medium flows between the two piston-based cavities of the hydraulic cylinder, and the internal friction and boundary friction of the viscous liquid produce damping. . This process converts the mechanical energy of the piston into heat energy, which consumes a certain amount of energy.

Existing speed dampers are generally single-stage energy-consuming devices, which have a relatively good damping effect on vibrations generated when heavy vehicles pass by, but have relatively limited protection against destructive vibrations generated by some tectonic earthquakes.

Chinese patent document CN106838099A proposes a viscous damper with variable parameters, which can automatically adjust the damping coefficient and the speed index according to the change of the speed of the damping valve. First of all, its basic structure is still based on the piston structure to achieve damping. There is a damping valve on the piston. The opening of the damping valve changes based on the response to the speed, so it has a relatively strong adaptability to various levels of vibration. However, it is still a single-piston structure in essence. Although it has good adaptability to various speeds, its application is still limited due to the limitation of its working stroke.

Chinese patent document CN1916288A discloses a method based on parallel use of a fluid damper and an MR damper to suppress the longitudinal vibration response of the bridge girder caused by train braking and train running. This type of structure works better when the vibration is relatively small, but for scenes such as earthquakes that may have a large longitudinal amplitude in a short period of time, due to the parallel use, the overall stroke remains unchanged compared with a single damping method, and the effect The effect is not great.

The Chinese patent document CN205155007U adopts the method of setting a prestressed spring in the cylinder to realize the automatic reset of the viscous damper. The prestressed spring can also play a certain role in energy consumption during the movement of the piston. It belongs to composite energy consumption, but the energy storage effect generated by the deformation of the prestressed spring is relatively limited, and the main function is also used for piston reset. The composite energy-dissipating structure can achieve a greater energy-dissipating effect within a shorter working stroke, and therefore increases the instantaneous load of, for example, the piston rod. Moreover, the auxiliary energy consumption part of the composite energy consumption is often not very effective, and there is no better damping device than viscous damping at present.

Contents of the invention

The object of the present invention is to provide a speed damper that can satisfy both minor vibration buffering and relatively large vibration buffering.

According to an embodiment of the present invention, a speed damper is provided, which includes a cylinder, a piston disposed in the cylinder and having an axial damping hole, and a piston rod connected to the piston, and the inner chamber of the cylinder is divided in the axial direction The body is divided into a first cavity and a second cavity, and a central via hole is opened on the separator;

The piston includes a first piston located in the first cavity and a second piston located in the second cavity;

The piston rod then includes a first piston rod connected to the first piston and a second piston rod connected to the second piston, and the first piston and the first piston rod have a given connection strength;

Wherein, the diameter of the second cavity is greater than the diameter of the first cavity;

The first piston rod passes through the cylinder body and is connected with the corresponding bridge support;

During the working stroke of the first piston, the first piston rod is disengaged from the second piston rod, and engages with the second piston rod in the central through hole when the first piston reaches the side dead center where the second cavity is located.

In the above speed damper, optionally, at least within the working stroke of the first piston, the first piston rod is in an engaged state with the central through hole.

Optionally, one end of the first piston rod engaging with the second piston rod is provided with a tapered hole, and correspondingly, the second piston rod is provided with a tapered head engaging with the tapered hole at the corresponding end.

Optionally, the first piston rod is radially provided with a connecting pin connected with the first piston.

Optionally, the rod section of the first piston rod used to connect with the first piston has an axially distributed toothed connection structure.

Optionally, the cylinder body is an assembled structure of two semicircular shells;

The fastening connection between two semicircular shells is based on the bolt group normal to the joint surface of the two semicircular shells.

Optionally, the diameter of the second piston is 1.2-1.8 times the diameter of the first piston.

Optionally, the damping holes are arranged in an annular array on the piston, and the diameter of the annular array is three quarters of the diameter of the piston.

Optionally, the number of damping holes is 12.

Optionally, the main body of the damping hole is a cylindrical hole, and both ends are tapered holes;

Wherein, the taper of the tapered hole is 1:1~1:3.

According to an embodiment of the present invention, a cavity in a cylinder is divided into two cavities by a partition with a central via hole, wherein a first piston is set in one cavity, and a second piston is set in the other cavity, corresponding to The first piston rod and the second piston rod are disengaged within the working stroke of the first piston, so that only the damping formed by the first cavity and the first piston works when the vibration is small. When a strong earthquake comes, the first piston cannot completely consume energy when it moves to the dead point. At this time, the connection between the first piston and the first piston rod fails due to the shear at the dead point, and the first piston rod overstrokes. While engaging the second piston rod, the damping formed by the second piston and the second cavity comes into play. The above involves three damping links, and the second piston is larger than the first piston, which can form greater damping and can play a good shock absorption effect. It can be seen from the above that the speed damper based on the present invention can satisfy the damping requirements for relatively small vibrations, and can also satisfy the damping requirements for relatively large vibrations.

Description of drawings

Fig. 1 is a schematic diagram of the main sectional structure of a speed damper according to the present invention.

Fig. 2 is an enlarged view of part A of Fig. 1 .

Fig. 3 is a schematic diagram of the side structure of the piston.

Figure 4 is a schematic diagram of the damping hole structure.

1. Universal ball joint, 2. The first piston rod, 3. The first cavity, 4. The first damping plate, 5. Through hole, 6. The first cavity, 7. The second damping block, 8. The first Two piston rods, 9. cylinder block, 10. connecting bolt, 11. connecting pin, 12. toothed connection structure, 13. damping hole, 14. connecting hole.

Detailed ways

Referring to the accompanying drawing 1 of the specification, a speed damper is roughly its structural diagram in use, and is used for horizontally connecting the bridge support or two components that are connected to the bridge support with relative movement in the horizontal direction. Cushioning, or damping.

The universal spherical joint 1 in Fig. 1 and the connecting part at the right end of the speed damper in the figure are used for the assembly of the speed damper on the bridge support.

Same as the conventional speed damper, the speed damper based on the embodiment of the present invention generally has a hydraulic cylinder structure, but the medium used is generally a viscous liquid with a relatively high viscosity. At the same time, it is different from the conventional hydraulic cylinder. The piston of the speed damper generally has a damping hole 13. When the piston is actuated to run, the damping material enters the opposite side of the piston running direction through the damping hole 13 to produce a viscous effect, that is, damping.

For the speed damper, its cylinder body 9 is roughly a cylindrical cylinder, which can be a tubular body with end caps at both ends and a separator in the middle. When processing, process from both ends and leave a separator at a given position , can be seen in FIG. 1 about the separator, that is, the part with the via hole 5 .

In order to reduce leakage, the cylinder body 9 can adopt the structure of two semi-cylindrical seals, the end cover can be omitted, and the leakage point at the end can be reduced, and there are no direct moving parts on the split surface of the two semi-cylindrical bodies , and a sealing structure with a relatively high sealing level can be used, which is not easy to cause leakage.

The two semi-cylindrical shells are essentially semi-cylindrical shell structures, and the two semi-cylindrical shells are connected by a bolt set perpendicular to the joint surface of the two and matched with a seal.

In FIG. 1 , the through hole 5 is a central through hole for fitting the piston rod, and the “center” involved passes through or is on the axis of the cylinder 9 .

The two pistons are configured into two sets of damping structures, which are denoted as the first damping structure and the second damping structure, wherein the first damping structure works first, and the second damping structure works later. It should be noted that this does not mean that only two damping structures produce damping effects based on damping. In the figure, in order to satisfy the function of the second damping structure, the first damping plate 4 as the first piston needs to run to the right end in the figure. After the dead point, the first piston rod 2 can continue to move right. At this time, the initial connection structure between the first damping plate 4 and the first piston rod 2 is destroyed, and the destruction needs to consume a certain amount of energy. After the initial connection structure is broken, there will still be friction between the first piston rod 2 and the first damping plate 4 , that is, frictional damping can also be generated between the connection hole 14 of the first damping plate 4 and the first piston rod 2 .

In Fig. 1, part of the first piston rod 2 and part of the second piston rod 8 are guided in the through hole 5. Due to the high viscosity of the damping medium, under the condition that the two piston rods are reliably guided, the distance between the piston rod and the through hole 5 The gap is so small that there will be no leakage of the damping medium between the first cavity 3 and the second cavity 6 .

Furthermore, regarding the first damping plate 4, its assembly on the first piston rod 2 must have a corresponding connection strength, which can be effectively controlled based on mechanical design, so that a given connection strength can be designed according to energy consumption conditions , when the first damping plate 4 moves to the right dead center in the figure, it is further pushed by the first piston rod 2, which may cause the initial connection between the first damping plate 4 and the first piston rod 2 to be destroyed.

Furthermore, the first piston rod 2 moves further to the right and engages with the second piston rod 8 to realize power transmission. At this time, the second piston, that is, the second damping plate 7 shown in FIG. The right side of the second damping plate 7 enters the left side of the second damping plate 7 through the damping hole 13 to generate damping, and enters the second stage of damping. Note that the stage in which the first damping plate 4 works alone is the first stage.

In the second stage of damping, even if the size of the first damping plate 4 and the second damping plate 7 are the same, the damping produced in the second stage is larger than that in the first stage. In a preferred embodiment, the diameter of the second cavity 6 is larger than that of the first cavity 3 , and the second damping plate 7 has a larger pressure-bearing area.

In order to realize the conversion from the first stage to the second stage, as shown in Fig. 1, it is necessary to disengage the first piston rod 2 from the second piston rod 8 in the first stage, and in the first stage, the speed damper is mainly used for small Vibrations are damped.

In the first stage, at least one of the first piston rod 2 and the second piston rod 8 is engaged with the through hole 5 , so that the damping medium can be prevented from entering the second cavity 6 from the first cavity 3 .

In the first stage, the preferred state is that the first piston rod 2 is always engaged with the through hole 5 to form a dynamic sealing structure.

Regarding the conversion from the first stage to the second stage, it is necessary to naturally undertake on the working stroke, that is, the first stroke of the first piston and the second stroke of the second piston should be undertaken, and the maximum stroke of the first piston rod 2 is The sum of the first stroke and the second stroke.

On the whole, when the first stage ends, the second stroke is naturally accepted, so the first piston rod 2 is required to be just engaged with the second piston rod 8 when the first stroke is at the right dead center in FIG. 1 .

Regarding the engagement of the first piston rod 2 and the second piston rod 8, it may be an end-to-end end face engagement. In a preferred embodiment, in order to improve the reliability of the engagement, as shown in Figure 1, the first piston rod 2 and the second piston rod One end where the two piston rods 8 are connected is provided with a tapered hole, and correspondingly, the second piston rod 8 is provided with a tapered head which is connected with the tapered hole at the corresponding end.

It is obvious that the taper of the tapered head and the tapered hole is the same, and when the top surface of the tapered head engages with the bottom of the tapered hole, the conical surface of the tapered head and the conical surface of the tapered hole just fit together, avoiding Bulging that produces a tapered hole.

In FIG. 2 , the first piston rod 2 is radially provided with a connecting pin 11 connected to the first piston (the first damping plate 4 shown in the figure).

In order to facilitate the penetration of the connecting pin 11, radial holes need to be opened on the first piston.

In addition, as shown in FIG. 2, the rod section of the first piston rod 2 used to connect with the first piston has an axially distributed toothed connection structure 12. After the connecting pin 11 and the toothed connection structure 12 are destroyed, Due to the tooth profile, it also produces greater frictional damping.

In addition, the tooth profile can be provided separately on the connecting hole 14 and not provided on the corresponding piston rod.

Regarding the size of the two pistons, as shown in Figure 1, the second damper plate 7 as the second piston is obviously larger than the first piston, that is to say, when the second stage is required to work, it shows that the bridge may be subjected to a relatively large Shocks, rather than simple vibrations such as vehicle brakes, require greater damping.

Considering that there is still an effect between the first piston and the first piston rod 2 when it works in the second stage, in order to make the overall structure more compact, the second piston is not easy to be too large. Preferably, the diameter of the second piston is the first 1.2~1.8 times the diameter of a piston.

Regarding the damping hole 13, the effect of damping is found by the inventors. In addition to the opening ratio and the size of the opening, it is also related to the distribution of the damping hole 13. The damping hole is biased on the centrifugal side of the piston, which can produce more Good damping effect.

In a preferred embodiment, the damping holes 13 are arranged in an annular array on the piston, and the diameter of the annular array is preferably three-quarters of the diameter of the piston, so that better control of the opening ratio can be obtained.

Further preferably, the number of damping holes is 12.

In addition, the current damping hole 13 is generally a round hole, and the drilling process of the round hole is simple. Generally, a row of drills can be used to form it at one time, but the damping effect is limited.

In the structure shown in Figure 4, the main body of the damping hole 13 is a cylindrical hole, and the two ends are tapered holes, which can produce a relatively good boundary friction effect. Under the condition that the flow velocity of the damping medium is not affected, the damping effect is relatively good. high lift.

In the figure, the maximum diameter of the tapered hole is H, and the minor diameter is also the diameter of the cylindrical hole is h. Preferably, the value of H on the first damping plate 4 is 8, and the value of h is 4 mm; the value of H on the second damping plate 7 is 4, and the value of h is 2 mm.

Claims (8)

1. The speed damper comprises a cylinder body, a piston arranged in the cylinder body and provided with an axial damping hole, and a piston rod connected to the piston, and is characterized in that the inner cavity of the cylinder body is divided into a first cavity and a second cavity in the axial direction by a partition body, and the partition body is provided with a central through hole;

the piston comprises a first piston positioned in the first cavity and a second piston positioned in the second cavity;

the piston rod comprises a first piston rod connected to the first piston and a second piston rod connected to the second piston, and a given connection strength is arranged between the first piston and the first piston rod; correspondingly, the first piston rod is radially provided with a connecting pin connected with the first piston;

wherein the second cavity diameter is greater than the first cavity diameter;

the first piston rod penetrates out of the cylinder body and is connected with the corresponding bridge support;

in the working stroke of the first piston, the first piston rod is separated from the second piston rod, and is engaged with the second piston rod in the central through hole when the first piston reaches the side dead point of the second cavity;

the diameter of the second piston is 1.2-1.8 times of that of the first piston.

2. A speed damper according to claim 1, wherein the first piston rod is in engagement with the central bore at least during the working stroke of the first piston.

3. A speed damper according to claim 1 or 2, wherein the end of the first piston rod engaging the second piston rod is provided with a conical bore, and the second piston rod is provided with a conical head engaging the conical bore at the respective end.

4. A speed damper according to claim 1, wherein the rod section of the first piston rod for connection with the first piston has an axially distributed tooth connection.

5. The speed damper of claim 1, wherein the cylinder is a combination of two semi-circular shells;

the two semicircular shells are fastened and connected based on a bolt set normal to the joint surface of the two semicircular shells.

6. A speed damper according to claim 1, wherein the damping holes are in an annular array on the piston, the diameter of the annular array being three-quarters of the diameter of the piston.

7. The speed damper of claim 6 wherein the number of damping holes is 12.

8. A speed damper according to claim 1, 6 or 7, wherein the body of the damping hole is a cylindrical hole and both ends are tapered holes;

wherein the taper of the taper hole is 1:1-1:3.

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